Anh Văn Chuyên Ngành Cơ Khí

🔙 Quay lại trang tải sách pdf ebook Anh Văn Chuyên Ngành Cơ Khí Ebooks Nhóm Zalo PGS.TS LÊ CHÍ CƯƠNG GIÁO TRÌNH ANH VĂN CHUYÊN NGÀNH CƠ KHÍ PGS.TS LÊ CHÍ CƯƠNG GIÁO TRÌNH NHÀ XUẤT BẢN ĐẠI HỌC QUỐC GIA THÀNH PHỐ HỒ CHÍ MINH – 2016 LỜI NÓI ĐẦU Việt Nam đang trong quá trình hội nhập kinh tế toàn cầu, trong đó nhiều lãnh vực sản xuất mũi nhọn của nền kinh tế quốc dân đang có nhu cầu cấp thiết về cập nhật và chuyển giao công nghệ, đáng kể nhất là cơ khí, vật liệu học và tự động hóa. Song song với quá trình học tập và nghiên cứu chuyên môn, việc nâng cao năng lực tiếng Anh cho sinh viên hệ ngành cơ khí và trang bị cho kỹ sư mới ra trường khả năng sẵn sàng làm việc để đáp ứng nhu cầu hội nhập và nâng cao khả năng cạnh tranh của nguồn nhân lực trong nước là một công việc quan trọng và cần thiết. Trước nhu cầu đó, nhóm tác giả, với kinh nghiệm nghiên cứu, làm việc trong lãnh vực chuyên ngành và ngôn ngữ dịch thuật đã mạnh dạn biên soạn Giáo trình Anh văn Chuyên ngành Cơ khí cho sinh viên đại học và cao đẳng thuộc nhóm ngành cơ khí để nâng cao khả năng ngoại ngữ. Cuốn sách cũng nhằm muốn chia sẻ, trao đổi kiến thức và ngôn ngữ với đông đảo bạn đọc có nhu cầu học thêm tiếng Anh về cơ khí. Giáo trình bao gồm 13 bài với các phần từ vựng, bài đọc, luyện tập cấu trúc câu và ngữ pháp được biên soạn theo hình thức vừa là bài giảng cho giảng viên, vừa là phần tự học cho sinh viên. Các cấu trúc và văn phạm được luyện tập là những cấu trúc rất cơ bản và thường gặp trong lãnh vực kỹ thuật mà người kỹ sư ra trường cần trang bị. Dù giáo trình đã được biên soạn công phu, cập nhật, nhưng vẫn không khỏi những sai sót. Chúng tôi mong nhận được những ý kiến bổ sung, đóng góp để cuốn sách ngày càng hoàn thiện và bổ ích cho các bạn đọc. Mọi ý kiến đóng góp xin gửi về: PGS.TS Lê Chí Cương Khoa Cơ khí Chế tạo máy Trường Đại học Sư phạm Kỹ thuật TP HCM [email protected] hoặc [email protected] 3 MỤC LỤC Unit 1: Engineering - What's it all about? .................................................5 Unit 2: Engineering Materials .................................................................15 Unit 3: Mechanisms.................................................................................29 Unit 4: Forces in Engineering..................................................................41 Unit 5: Washing Machine........................................................................53 Unit 6: Robotics.......................................................................................71 Unit 7: Lasers...........................................................................................85 Unit 8: Corrosion .....................................................................................95 Unit 9: Plastic Injection Moulding ........................................................103 Unit 10: Welding Technology ...............................................................113 Unit 11: Computer Integrated Manufacturing .......................................123 Unit 12: Special Machining Technologies ............................................129 Unit 13: Applying for a Job ...................................................................137 Tài liệu tham khảo .................................................................................147 4 Unit 1 ENGINEERING - WHAT'S IT ALL ABOUT? Task 1. Warm-up 1. What is your major? 2. Discuss with your friends and make a list of technical majors in HCMC University of Technology and Education. Task 2. List main branches of engineering. Combine your list with others in your group. Then read this text to find out how many branches listed are mentioned. Engineering is largely a practical activity. It is about putting ideas into 5 action. Civil engineering is concerned with making bridges, roads, airports, etc. Mechanical engineering deals with the design and manufacture of tools and machines. Electrical engineering is about the generation and distribution of electricity and its many applications. Electronic engineering is concerned with developing components and equipment for communications, computing, and so on. Mechanical engineering includes marine, automobile, aeronautical, 10 heating and ventilating, and others. Electrical engineering includes electricity generating, electrical installation, lighting, etc. Mining and medical engineering belong partly to mechanical and partly to electrical. Task 3. Complete this diagram using the information from the text above. Engineering Civil 1 Electrical 2 3 5 6 electrical 4 automobile aeronautical 7 installation 8 medical 5 Reading Introduction In your study and work, it is important to think about what you are going to read before reading. This helps you to link old and new knowledge and make guesses the content and meaning of new words in the text. It is also important to have a clear purpose so that you can choose the best way to read. In this book, you will find tasks to make you think before you read and tasks to help you to have a clear purpose when you read. Task 4. Study these illustrations. They show some of the areas in which engineers work. Can you identify them? What kinds of engineers are concerned with these areas - electrical, mechanical, and both? Figure 1. Fields of engineering Task 5. Now read the following texts to check your answers to Task 4. Match each text to one of the illustrations above. Transport: Cars, trains, ships, and planes are all products of mechanical engineering. Mechanical engineers are also involved in support services such as roads, rail track, harbours, and bridges. 5 Food processing: Mechanical engineers design, develop, and make the machines and the processing equipment for harvesting, preparing and preserving the foods and drinks that fill the supermarkets. 6 Medical engineering: Body scanners, X-ray machines, life-support systems, and other high-tech equipment result from mechanical and electrical engineers combining with medical experts to convert ideas into life-saving and preserving products. 10 Building services: Electrical engineers provide all the services we need in our homes and places of work, including lighting, heating, ventilation, air-conditioning, refrigeration, and lifts. 15 Energy and power: Electrical engineers are concerned with the production and distribution of electricity to homes, offices, industry, hospitals, colleges and schools, and the installation and maintenance of the equipment involved in these processes. Task 6. Answer these following questions. 1. What are the products of mechanical engineering in transport? 2. What do mechanical engineers do in food processing? 3. How is mechanical engineering applied in medical engineering? 4. What is the role of electrical engineer in building services? 5. What is the concern of electrical engineers in energy and power sectors? Language study deal with / be concerned with What is the link between column A and column B? A B Mechanical Machines Electrical Electricity Column A lists branches of engineering or types of engineer. Column B lists things they are concerned with. We can show the link between them in a number of ways: 1. Mechanical engineering deals with machines. 2. Mechanical engineers deal with machines. 3. Mechanical engineering is concerned with machines 4. Mechanical engineers are concerned with machines. 5. Machines are the concern of mechanical engineers. 7 Task 7. Match each item in column A with an appropriate item from column B and link them to make a sentence. A B 1 marine a air-conditioning 2 aeronautical b roads and bridges 3 heating and ventilating c body scanners 4 electricity generating cables and switchgear 5 automobile d communications and equipment 6 civil e ships 7 electronic f planes 8 electrical installation g cars and trucks 9 medical h power stations Task 8. Building your vocabulary. Noun Verb Adjective 1. machine/machinery _______________ _______________ 2._______________ _______________ electrical/ electric 3. practice _______________ _______________ 4. industry _______________ _______________ 5._______________ produce _______________ 6. installation _______________ 7._______________ maintain _______________ 8. process/processing _______________ _______________ 9. ventilation _______________ _______________ 10.______________ distribute _______________ 8 Task 9. Fill in the gaps in the following text which describes different branches of engineering. (Use words of the diagram in Task 3 and languages you have studied in this unit.) The main branches of engineering are civil, 1__________, 2__________, and electronic. Mechanical engineering is 3__________ 4__________machinery of all kinds. This branch of engineering includes 5__________, automobile 6_________, and heating and ventilating. The first three are concerned with transport: 7___________, cars and planes. The last 8__________ with air-conditioning, refrigeration, etc. Electrical engineering deals with 9__________ from generation to use. Electricity generating is concerned with 10__________ stations. Electrical installation deals 11__________ cables, switchgear, and connecting up electrical equipment. Two branches of engineering include both 12__________ and 13_________ engineers. These are mining and 14__________ engineering. The former deals with mines and mining equipment, the latter with hospital 15_________ of all kinds. VOCABULARY − to act (v) /ækt/ hành động activity (n) /æk'tɪ vɪ ti/ hoạt động active (adj) /'æktɪ v/ năng động action (n) /'æk∫n/ hành động, hành vi; hoạt động − aeronautical(adj) /ˌ eərəˈ nɔ ː tɪ kl/ (thuộc) hàng không − application (n) /ˌ æplɪ ˈ keɪ ʃ n/ sự áp dụng, sự ứng dụng − automobile (n) /ˈ ɔ ː təməbiː l/ xe ô tô − branch (n) /brɑ ː ntʃ / nhánh, ngành − bridge (n) /brɪ dʒ / cầu − cable (n) /ˈ keɪ bl/ cáp − civil (adj) /ˈ sɪ vl/ thuộc công dân, dân dụng − to combine (v) /kəmˈ baɪ n/ kết hợp, phối hợp − to communicate (v)/kəˈ mjuː .nɪ .keɪ t/ liên lạc, giao tiếp 9 communication (n) /kəˌ mjuː nɪ ˈ keɪ ʃ n/ sự liên lạc communications(n) những phương tiện liên lạc − component (n) /kəmˈ pəʊ nənt/ thành phần − to compute (n) /kəmˈ pjuː t/ tính toán − to be concerned(v) /kənˈ sɜ ː nd/ liên quan − to be about liên quan, về − to deal with(v) /diː l/ đề cập đến − to design (v) /dɪ ˈ zaɪ n/ thiết kế − to develop (v) /dɪ ˈ veləp/ phát triển − to distribute(v) /dɪ ˈ strɪ bjuː t/ phân phối distribution (n) /ˌ dɪ strɪ ˈ bjuː ʃ n/ sự phân phối − electrify (v) /ɪ 'lektrɪ faɪ / điện khí hóa electricity (n) /ɪ ˌ lekˈ trɪ səti/ điện lực electrical (adj) /ɪ ˈ lektrɪ kl/ thuộc về điện electric (adj) /ɪ 'lektrɪ k/ dùng điện, chạy bằng điện electronic (adj) /ɪ ˌ lekˈ trɒ nɪ k/ thuộc về điện tử − engine (n) /ˈ en.dʒ ɪ n/ máy, động cơ engineer (n) /ˌ endʒ ɪ ˈ nɪ ə(r)/ kỹ sư engineering(n) /ˌ endʒ ɪ ˈ nɪ ərɪ ŋ/ kỹ thuật − equipment (n) /ɪ ˈ kwɪ pmənt/ đồ trang bị, trang thiết bị − former (adj) /ˈ fɔ ː mə(r)/ trước − food processing(n) /'prousesɪ η/ chế biến thực phẩm − to generate (v) /ˈ dʒ enəreɪ t/ phát, phát ra generation (n) /ˌ dʒ enəˈ reɪ ʃ n/ sự phát điện generator (n) /'dʒ enəreɪ tə/ máy phát điện − harbour (n) /ˈ hɑ ː bə(r)/ bến cảng − to harvest (v) /ˈ hɑ ː vɪ st/ gặt hái, thu hoạch − idea (n) /aɪ ˈ dɪ ə/ ý tưởng − to install (v) /in'stɔ :l/ lắp đặt 10 installation (n) /ˌ ɪ nstəˈ leɪ ʃ n/ sự lắp đặt hoặc được lắp đặt − to involve (v) /ɪ nˈ vɒ lv/ gồm, bao hàm − latter (adj) /ˈ lætə(r)/ sau cùng − machine (n) /məˈ ʃ iː n/ máy, cỗ máy mechanical (adj) /məˈ kæn.ɪ .kl/ thuộc về cơ khí − maintenance (n) /ˈ meɪ ntənəns/ sự bảo dưỡng, bảo trì − to manufacture (v, n) /ˌ mænjuˈ fæktʃ ə(r)/ sản xuất, chế tạo − marine (adj) /məˈ riː n/ (thuộc) ngành hàng hải − medical (adj) /ˈ medɪ kl/ thuộc về y tế, y học − mining (n) /ˈ maɪ nɪ ŋ/ sự khai mỏ − to prepare (v) /prɪ ˈ peə(r)/ chuẩn bị − to preserve (v) /prɪ ˈ zɜ ː v/ bảo quản, giữ gìn − process (n) /ˈ prəʊ ses/ quá trình; quy trình − to produce (v) /prəˈ djuː s/ làm, sản xuất, chế tạo product (n) /ˈ prɒ dʌ kt/ sản vật, sản phẩm production (n) /prə'dʌ k∫n/ sự sản xuất, sự chế tạo − to provide (v) /prəˈ vaɪ d/ cung cấp; cung ứng − service (n) /ˈ sɜ ː vɪ s/ sự phục vụ − to support (v) /səˈ pɔ ː t/ cung cấp, hỗ trợ − system (n) /ˈ sɪ stəm/ hệ thống − tool (n) /tuː l/ công cụ, dụng cụ − to ventilate (v) /ˈ ventɪ leɪ t/ làm cho thông gió, thông hơi REVIEW Choose the best answer for the following sentences. 1. Engineering, which is about putting __________ into action, is largely a practical activity. A. generation B. distributions C. ideas D. equipment 11 2. __________ is concerned with making bridges, roads, airports, etc. A. Mechanical engineering B. Electrical engineering C. Electronic engineering D. Civil engineering 3. Electrical engineering __________ electricity generating, electrical installation, lighting, etc. A. generates B. produces C. includes D. makes 4. Mining and medical engineering belong partly to __________ and partly to electrical A. electronic B. civil C. aeronautical D. mechanical 5. Cars, trains, ships and planes are all __________ of mechanical engineering. A. serves B. systems C. components D. products 6. The main __________ of engineering are civil, mechanical, electrical and electronic. A. systems B. offices C. branches D. services 7. Mechanical engineering __________ with design and manufacture of tool and machines. A. concerned B. is C. is concern D. deals 8. Electrical engineering is concerned with electricity from ___________ to use. A. generation B. installation C. transportation D. communication 9. Two branches of engineering including both mechanical and electrical engineers are mining and medical engineering ___________ deals with mines and mining equipment, __________ with hospital equipment of all kinds. A. The former/ the latter B. A former/ a latter C. The latter/ the former D. A latter/ a former 10. Electricity generating is concerned with __________. A. products B. services C. supply D. power stations 12 11. The aim of design engineers is to ____ new components to make the product cheaper or stronger. A. repair B. install C. introduce D. fit Translate into Vietnamese Mechanics is, in the most general sense, the study of forces and their effect upon matter. Typically, engineering mechanics is used to analyze and predict the deformation process (both elastic and plastic) of objects under known loads or stresses. Structural analysis is the branch of mechanical engineering (and also civil engineering) devoted to examining why and how objects fail and to fix the objects and their performance. Structural failures occur in two general modes: static failure and fatigue failure. Thermodynamics is an applied science used in several branches of engineering, including mechanical and chemical engineering. Thermodynamics is the study of energy, its use and transformation through a system. Typically, engineering thermodynamics is concerned with changing energy from one form to another. As an example, automotive engines convert chemical energy (enthalpy) from the fuel into heat, and then into mechanical work that actually turns the wheels. Drafting or technical drawing is the means by which mechanical engineers design products and create instructions for manufacturing parts. A technical drawing can be a computer model or hand-drawn schematic showing all the dimensions necessary to manufacture a part, as well as assembly notes, a list of required materials, and other pertinent information. Acoustical engineering is one of many other sub disciplines of mechanical engineering and is the application of acoustics. Acoustical engineering is the study of Sound and Vibration. These engineers work effectively to reduce noise pollution in mechanical devices and in buildings by soundproofing or removing sources of unwanted noise. Mechatronics is the combination of mechanics and electronics. It is an interdisciplinary branch of mechanical engineering, electrical engineering and software engineering that is concerned with integrating electrical and mechanical engineering to create hybrid systems. 13 Unit 2 ENGINEERING MATERIALS Task 1. Warm-up What materials do you know? Make a list and compare with your classmates. Task 2. Identify the materials below. Brass, ABS, Aluminium, Stainless steel, Copper, Epoxy resin, Nylon, Urea formaldehyde, Acrylic 15 Reading: Scanning tables In engineering it is important to practise reading tables, charts, diagrams, and graphs because so much information is presented in these ways. We will start this unit with a table. Scanning is the best strategy for finding information in a table. With scanning, you can know what sort of information you are searching for before reading. To scan a table, you move your eyes up and down the columns until you find the word or words you want. To scan quickly, you must learn to ignore any information which will not help you with your task. Task 3: Scan the table below to find the material which is … 1. soft 2. ductile 3. malleable 4. tough 5. scratch-resistant 6. conductive and malleable 7. durable and hard 8. stiff and brittle 9. ductile and corrosion-resistant 10. heat-resistant and chemical-resistant Materials Properties Uses Metals Aluminium Light, soft, ductile, highly conductive, corrosion resistant. Copper Very malleable, tough and ductile, highly conductive, corrosion-resistant. Aircraft, engine components, foil, cooking utensils. Electric wiring, PCBs, tubing. Brass (65% copper, 35% zinc) Very corrosion-resistant, casts well, easily machined. Can be hardened. Good conductor. Valves, taps castings, ship fittings, electrical contacts. 16 Mild steel (iron with 0.15% to 0.3% carbon) High carbon steel (iron with 0.7% to 1.4% carbon) Thermoplastics High strength, ductile, tough, fairly malleable. Cannot be hardened and tempered. Low cost. Poor corrosion resistance. Hardest of the carbon steels but less ductile and malleable. Can be hardened and tempered. General purpose Cutting tools such as drills, files, saws ABS High impact strength and toughness, scratch-resistant, light and durable. Acrylic Stiff, hard, very durable, clear. Can be polished easily. Can be formed easily. Nylon Hard, tough, wear-resistant, self-lubricating. Thermosetting plastics Epoxy resin High strength when reinforced, good chemical and wear resistance. Polyester resin Stiff, hard, brittle. Good chemical and heat resistance. Urea formaldehyde Stiff, hard, strong, brittle, heat-resistant, and a good electrical insulator. Safety helmets, car components, telephones, kitchenware. Aircraft canopies, baths, double glazing Bearings, gears, casings for power tools Adhesives, encapsulation of electronic components Molding, boat and car bodies Electrical fittings, adhesives 17 Grammar Be + used to + V0 Be + made of Be + used for + Noun/Gerund (V-ing) Language study: Making definitions and describing materials using “which” Study these facts from the table about aluminium: 1. Aluminium is a light metal. 2. Aluminium is used to make aircraft. We can link these facts to make a definition of aluminium: (1+2) Aluminium is a light metal which is used to make aircraft. or we can describe aircraft: Aircraft are made of aluminium, which is a light metal. or: Aluminium, which is a light metal, is used for making aircraft. Task 4. Define each of the materials in column A (see the table above). Choose the correct information in columns B and C to describe the materials in column A. A B C 1. An alloy allows heat or current to flow easily 2. A thermoplastic remains rigid at high temperatures 3. Mild steel a metal does not allow heat or current to flow easily 4. A conductor a material contains iron and 0.7% to 1.4% carbon 5. An insulator an alloy becomes plastic when heated 6. High carbon steel contains iron and 0.15% to 0.3% carbon 7. Brass formed by mixing other metals or elements 8. A thermosetting plastic consists of copper and zinc 18 Task 5. Complete the sentences. a. Epoxy resin, which is …………………………………, is used to……………………. …………….……………………………. b. Brass, which ……………………………….……., is used for ……………….……….. c. Thermosetting plastic, which ………………..…………., is used for…………………………………………………. d. Mild steel, which is an alloy containing ………………..…… ……………………………, is used for……... …………………. e. Urea formaldehyde, which is ………………………..………, is used to make……….. …………………such as …………….…. Task 6. What materials make these things? Use is/are made of. Ex: Safety helmets are made of ABS. 1. Bearings 2. A cam 3. Car bodies 4. Cutting tool 5. Wirings 6. A file 7. A valve Writing. Adding information to a text Study this text about aluminium. Aluminium is used to make aircraft, engine components, and many items for the kitchen. Or we can add extra information to the text: Aluminium, which is light, soft, and ductile, is used to make aircraft, engine components – for example, cylinder heads – and many items for the kitchen, such as pots. Note that the extra information is marked with commas or dashes, and linked by which, for example, such as. 19 Task 7. Add this extra information to the following texts of plastics. Extra information 1. Plastics can be molded into plates, car components, and medical aids. 2. Thermoplastics soften when heated many times. 3. Thermosetting plastics set hard and do not alter if heated again. 4. ABS is used for safety helmets. 5. Nylon is self-lubricating. 6. Nylon is used for motorized drives in cameras. 7. Acrylic is a clear thermoplastic. 8. Acrylic is used for aircraft canopies and double glazing. 9. Polyester resin is used for boat and car bodies. 10. Polyester resin is hard and has good chemical and heat resistance. Texts of plastics Plastics are synthetic materials. They can be softened and molded into useful articles. They have many applications in engineering. There are two types of plastics: thermoplastics and thermosetting plastics. ABS is a thermoplastic which is tough and durable. Because it has high impact strength, it has applications where sudden loads may occur. Nylon is a hard, tough thermoplastic. It is used when silent, low friction operation is required. Acrylic can be formed in several ways. It is hard, durable, and has many uses. Polyester resin is a thermosetting plastic used for castings. It has a number of useful properties. Task 8. Using suffixes -ness -ity -ility to make Nouns. Adjectives Nouns hard hardness soft ……………… rough ........................ 20 stiff ........................ tough ........................ damp ......................... ductile ductility elastic ........................ plastic ........................ flexible ........................ available ........................ intense ........................ humid ........................ compatible ........................ visco ........................ Task 9. Match each material in column A with its properties from column B. A B Wood Plastic, easily molded Metal Good total properties Glass Strong, conductive Plastics Brittle, clear Composite Light, stiff Task 10. How is it? Match the sentences to find the answers. 1. It’s flexible. a. When you heat it, it doesn’t burn or deform. 2. It’s rigid. b. When you drop or strike it, it doesn’t break. 3. It’s hard. c. When you compress it, it doesn’t break or deform. 4. It’s tough. d. When you twist it, it doesn’t break or deform. 5. It’s elastic. e. You can’t bend it. 6. It’s heat-resistant. f. You can bend it as it doesn’t break. 21 7. It’s strong in tension. 8. It’s strong in g. You can stretch it and make it longer as it doesn’t break. compression h. When you pull it, it doesn’t stretch or break. 9. It has torsional strength i. You can’t scratch or cut it. Task 11. Read these descriptions of tests and write the right figure number in its gap. Materials-testing: Destructive tests The purpose of the tensile strength test (Fig………) is to discover whether a material will deform (change shape) or break when it is pulled apart. The material is secured with two clamps, one at each end. The clamps are pulled apart with specified force. The yield point (the point where the material deforms) and/or the breaking point (the point where the material breaks) is measured. This measurement shows you the tensile strength of the material. The aim of the impact resistance test (Fig……….) is to find out whether a material will bend or break when it is struck with force. The bottom of the material is placed in a clamp, so it stands vertically. A hammer strikes the material with a specified force. The yield point and/or the breaking point are measured. This indicates the impact resistance of the material. The objective of the compressive strength test (Fig………) is to find out if a material will deform or break when it is compressed. The material is secured in a clamp between a fixed head and a moving head. The moving head presses down on the material and the load is increased. The yield point and/or the breaking point are measured. This indicates the compressive strength of the material. 22 VOCABULARY − Acrylic (n) /əˈ krɪ lɪ k/ nhựa Acrylic − aircraft (n) /ˈ eəkrɑ ː ft/ máy bay − Aluminium (n) /ˌ æljəˈ mɪ niəm/ nhôm − bearing (n) /ˈ beərɪ ŋ/ ổ đỡ − Brass (n), (adj)/brɑ ː s/ đồng thau; bằng đồng thau − brittle (adj) /ˈ brɪ tl/ giòn, dễ gãy, dễ vỡ − carbon (n) /ˈ kɑ ː bən/ các-bon − to conduct (v) /kən'dʌ kt/ dẫn điện, dẫn nhiệt conductive (adj) /kənˈ dʌ ktɪ v/ có tính dẫn điện conductor (n) /kənˈ dʌ ktə(r)/ chất dẫn (điện, nhiệt) conductivity (n) /kɑ ː ndʌ k'tɪ vɪ ti/ dẫn suất − contact (n) /ˈ kɒ ntækt/ công tắc − Copper (n), (adj)/ˈ kɒ pə(r)/ đồng đỏ, bằng đồng đỏ − to corrode (v) /kə'roud/ ăn mòn corrosive (adj) /kə'rousɪ v/ tính ăn mòn corrosion (n) /kəˈ rəʊ ʒ n/ sự ăn mòn − ductile (adj) /ˈ dʌ ktaɪ l/ mềm, dễ uốn; dễ kéo sợi − durable (adj) /ˈ djʊ ərəbl/ có tính bền − engine (n) /ˈ endʒ ɪ n/ máy, động cơ − to file (v) /faɪ l/ dũa file (n) /faɪ l/ cái dũa − saw (n), (v) /sɔ ː / cái cưa, cưa − to machine (v) /məˈ ʃ i:n/ gia công (bằng cắt gọt) − to lathe (to turn) (v) /leɪ ð/ tiện − to mill (v) /mɪ l/ phay − to plane (v) /pleɪ n/ bào − to grind (v) /grɪ n/ mài 23 − to drill (n), (v) /drɪ l/ khoan, mũi khoan, máy khoan − to bore (v) /bɔ :/ doa − to temper (v) /ˈ tempə(r)/ ram (thép...) − to quench (v) /kwentʃ / tôi (thép...) − to anneal (v) /əˈ ni:l/ ủ − to form (v) /fɔ :m/ tạo hình − to deform (v) /dɪ ˈ fɔ :m/ biến dạng − to fit (v) /fɪ t/ lắp ghép, kết nối − fitting (n) /ˈ fɪ tɪ ŋ/ sự lắp ráp; (số nhiều) máy móc − foil (n) /fɔ ɪ l/ lá (kim loại) − to harden (v) /ˈ hɑ ː dn/ làm cứng (bằng cơ), tôi (bằng nhiệt) hardness (n) /ˈ hɑ ː d.nəs/ cứng (chống biến dạng dẻo cục bộ) − to insulate (v) /'ɪ nsjuleɪ t/ cách nhiệt, cách điện insulation (n) /ɪ nsju'leɪ ∫n/ sự cách nhiệt, cách điện insulator (n) /ˈ ɪ nsjuleɪ tə(r) /vật cách điện − malleable (adj) /ˈ mæliəbl/ dễ dát mỏng, dễ uốn − material (n) /məˈ tɪ əriəl/ vật liệu, vật chất − metal (n) /'metl/ kim loại − nylon (n) /ˈ naɪ lɒ n/ nhựa nylon − property (n) /'prɔ pəti/ đặc tính, tính chất − purpose (n) /ˈ pɜ ː pəs/ mục đích, ý định − resist (v) /rɪ 'zɪ st/ chống lại resistance (n) /ri'zɪ stəns/ điện trở resistant (adj) /rɪ ˈ zɪ stənt/ chịu được − soft (adj) /sɒ ft/ mềm soften (v) /'sɔ fn/ làm mềm softness (n) /'sɔ ftnəs/ độ cứng − stiff (adj) /stɪ f/ cứng (không dễ uốn, gấp… ) 24 stiffness (n) /ˈ stɪ f.nəs/ cứng vững (đàn hồi toàn phần) − strength (n) /streŋθ/ sức bền; độ bền − thermoplastic (n), (adj) /ˌ θɜ ː məʊ ˈ plæstɪ k/ nhựa dẻo nóng − thermosetting plastic (n), (adj) nhựa nhiệt rắn − clear (adj) /klɪ ər/ trong suốt − transparent (adj) /trænˈ spærnt/ trong suốt transparency (n) /trænˈ spærnsi/ sự trong suốt − tough (adj) /tʌ f/ chắc, bền, dai toughness (n) /ˈ tʌ f.nəs/ độ bền, dai − tubing (n) /ˈ tjuː bɪ ŋ/ tuốc-bin − utensil (n) /juː ˈ tensl/ đồ dùng, dụng cụ (trong gia đình) − valve (n) /vælv/ van − wiring (n) /ˈ waɪ ərɪ ŋ/ dây điện, hệ thống dây điện REVIEW Choose the best answer. 1. Aluminium, which is a light, __________ and ductile metal, is used to make aircraft, engine components, foil, and cooking utensils. A. tough B. soft C. clear D. hard 2. Copper, which is very _____________, tough and ductile and highly conductive, is used to make electric wiring, PCBs and tubing. A. less conductive B. malleable C. hard D. tough 3. Safety helmet, car components, telephones and kitchen wares are made of ABS, which has high __________ and toughness. A. contacts B. impact strength C. plastics D. high conductive 4. Manufacturers use acrylic, which is stiff, hard, very durable and __________ to make aircraft, canopies, baths, and double glazing. A. clear B. clean C. malleable D. ductile 25 5. Acrylic can be polished and __________ easily. A. performed B. restrained C. reinforced D. formed 6. Bearing, gears and casings for power tools are made of nylon, which is hard, tough and __________. A. tear-resistant B. clean C. rusted D. wear-resistant 7. Epoxy, polyester resin and urea formaldehyde are called ___________. A. thermosetting plastics B. thermoplastics C. carbon steel D. power tools 8. Mild steel is a metal which contains iron and __________ carbon. A. 0.3% to 4.5% B. 0.7% to 1.4% C. 0.15% to 0.3% D. 0.15% to 0.35% 9. Aluminium __________ to make aircraft is light, soft, and ductile. A. is used B. uses C. which used D. used 10. Plastics are ____________ materials which can be softened and _____________ into useful articles. A. synthetic/ molded B. complex/ molded C. complex/ helpful D. synthetic/ helpful Translate into Vietnamese PLASTICS There are two types of plastics: Thermoplastic, which softens when heated many times, and thermosetting plastic, which sets hard and does not alter if heated again. Nylon, which is self-lubricating, is a hard, tough thermoplastic. It is used where silent, friction free operation is required – for example, motorized drives in cameras. ALUMINIUM Aluminium is the most common metallic element on earth, making up about 8% of the earth's crust, concentrated in the outer 16 km. It is the most widely used non-ferrous metal today. Aluminium never occurs in its 26 metallic form in nature. It occurs in various forms in most rocks and soils and is also present in gemstones like topaz and garnet. It can be found in vegetation and in all of the earth's water. Aluminium is also present in all clays, so it has been a constituent of cooking vessels since earliest civilisations. COPPER Copper is a chemical element with the symbol Cu and having atomic number 29. It is a ductile metal, with very high thermal and electrical conductivity. Pure copper is rather soft and malleable, and a freshly exposed surface has a reddish-orange color. It is used as a thermal conductor, an electrical conductor, a building material, and a constituent of various metal alloys. COMPOSITES Composite materials (also called composition materials or shortened to composites) are materials made from two or more constituent materials with significantly different physical, chemical or mechanical properties, that when combined, produce a material with characteristics different from the individual components. CUTTING TOOL MATERIALS (Society of Manufacturing Engineers – SME) Carbide is used in solid round tools or in the form of replaceable inserts. Every manufacturer of carbide tools offers a variety for specific applications. The proper choice can double tool life or double the cutting speed of the same tool. Shock-resistant types are used for interrupted cutting. Harder, chemically-stable types are required for high speed finishing of steel. More heat-resistant tools are needed for machining the super alloys, like Inconel and Hastelloy. There are no effective standards for choosing carbide grade specifications so it is necessary to rely on the carbide suppliers to 27 recommend grades for given applications. Manufacturers do use an ANSI code to identify their proprietary carbide product line. Two-thirds of all carbide tools are coated. Coated tools should be considered for most applications because of their longer life and faster machining. Coating broadens the applications of a specific carbide tool. These coatings are applied in multiple layers of under .001 of an inch thickness. The main carbide insert and cutting tool coating materials are titanium carbide, titanium nitride, aluminium oxide, and titanium carbonitride. Ceramic cutting tools are harder and more heat-resistant than carbides, but more brittle. They are well suited for machining cast iron, hard steels, and the super alloys. Two types of ceramic cutting tools are available: the alumina-based and the silicon nitride-based ceramics. The alumina-based ceramics are used for high speed semi- and final-finishing of ferrous and some non-ferrous materials. The silicon nitride-based ceramics are generally used for rougher and heavier machining of cast iron and the super alloys. Translate into English Khoa học vật liệu là một ngành nghiên cứu quan trọng và đang được khuyến khích phát triển tại Việt Nam. Tuy nhiên, việc này cần đầu tư nhiều thiết bị phức tạp và đắt tiền. Việc phát triển các vật liệu tiên tiến là cần thiết bởi vì ngành này liên quan đến rất nhiều lãnh vực công nghiệp quan trọng như cơ khí, xây dựng, điện-điện tử, và các ngành công nghiệp phụ trợ khác. Khoa học vật liệu cần các kiến thức nền tảng vững chắc về các ngành vật lý ứng dụng, hóa học, toán học kết hợp với các kiến thức chuyên ngành. Trong ngành cơ khí, ngoài các vật liệu thông dụng như thép, hợp kim nhôm, hợp kim đồng, ni-ken… các vật liệu như composite, gốm, và polymer cũng đang được nghiên cứu mạnh mẽ. 28 Unit 3 MECHANISMS Task 1. Identify these simple mechanisms. Explain the principles on which they operate. Reading: Scanning a text Scanning is the best strategy to search specific information in a text. Move your eyes up and down the text until you find the word or words you want. Again, try to ignore the information which does not help you with your task. Task 2. Scan the text opposite quickly to find out which of these mechanisms are mentioned. 1. cam 4. foot pump 2. tap 5. escalator 3. pendulum 29 Mechanisms Mechanisms are an important part of everyday life. They allow us to do simple things like switch on lights, turn taps, and open doors. They also make it possible to use escalators and lifts, travel in cars, and fly from continent to continent. Mechanisms play a vital role in industry. While many industrial 5 processes have electronic control systems, it is still mechanisms that deliver the power to do the work. They provide the forces to press steel sheets into car body panels, to lift large components from place to place, to force plastic through dies to make pipes. All mechanisms involve some kinds of motion. The four basic kinds of motion are: Rotary: Wheels, gears, and rollers involve rotary movement. 10 Oscillating: The pendulum of a clock oscillates – it swings backwards and forwards. Linear: The linear movement of a paper trimmer is used to cut the edge of the paper. Reciprocating: The piston in a combustion engine reciprocates. Many mechanisms involve changing one kind of motion into another type. For example, the reciprocating motion of a piston is 15 changed into a rotary motion by the crankshaft, while a cam converts the rotary motion of the engine into the reciprocating motion required operate the valves. Task 3. Identify what kind of motion. 1 2 30 3 4 1_____________________ 2________________________ 3_____________________ 4________________________ Task 4. Now read the text and find the answers to these questions. 1. What does a cam do? 2. What does oscillating mean? 3. How are plastic pipes formed? 4. What simple mechanisms in the home are mentioned directly or indirectly? 5. What is the function of a crankshaft? 6. Give an example of a device which can produce a linear movement. 7. How are car body panels formed? 8. What do mechanisms provide in industry? Grammar: Passive Voice Be + V-ed (Past participle) Example: The rotary motion is converted to reciprocating by a cam Weight is measured in newtons. Machines are designed by engineers 31 Task 5. Make passive sentences by using subjects and verbs provided. 1. Technicians, educate 2. Motions, convert 3. Volume, measure 4. Goods, manufacture 5. ABS, use 6. A drill, make Writing: Ways of linking ideas When we write, we may have to describe, argue, persuade, something, etc. In all these forms of writing, we use ideas. To make our writing more effective, we have to make sure our readers can follow our ideas. So it’s useful to use links between the ideas in our writing. What is the link of meaning of the 2 sentences below? What words are used for the connection? 1. Mechanisms are important to us. 2. They allow us to travel. Sentence 2 is the reason of Sentence 1 So, they can be linked like this: The mechanisms are important to us because they allow us to travel. Effect Conjunctions Cause The mechanisms are important to us because since as they allow us to travel. The football match has been cancelled because of due to owing to the rain. 3. Mechanisms deliver the power to do work. 4. They play a vital role in industry. Sentence 4 is the result of Sentence 3. So, they can be linked like this: 32 Mechanisms deliver power to do work; therefore, they play a vital role in industry. Cause Connectors Effect Mechanisms deliver power to do work; therefore, accordingly, as a consequence/result, because of this, consequently, hence, so, that’s why, thus, they play a vital role in industry. 5. Friction is sometimes a help. 6. It is often a hindrance. Sentence 6 contrasts with Sentence 5. So, they can be linked like this: Friction is sometimes a help but it is often a hindrance. Clause 1 Connector Clause 2 Friction is sometimes a help, Friction is sometimes a help; but/yet/still however, nevertheless, all the same, it is often a hindrance. Task 6. Connect these pairs of sentences by using proper linking words. 1. Copper is highly conductive. It is used for electric wiring. 2. Weight is measured in newtons. Mass is measured in kilograms. 3. Nylon is used for bearings. It is self-lubricating. 33 4. ABS has high impact strength. It is used for safety helmets. 5. The foot pump is a class 2 lever. The load is between the effort and the fulcrum. 6. Friction is essential in brakes. Friction is a nuisance in an engine. 7. The upper surface of a beam is in compression. The lower surface is in tension. 8. Concrete beams have steel rods near the lower surface. Concrete is weak in tension. Language study: Technical terms solving One of the difficult things about the field of engineering in English is that there are many technical terms to learn. Newer terms may be the same, or almost the same, in your own language. But many terms will be quite different and you may not always remember them. When this happens, you will have to use whatever English you know to make your meaning clear. 34 The same thing may happen in reverse when you know a technical term but the person you are communicating with does not recognize it. This may happen in the Speaking practice tasks in this book. Again, when this happens, you will have to make your meaning clear by using other words. Task 7. Match the meaning between the technical words in column A and the more general English in column B. A B 1. oscillates a. changes 2. rotates b. large, thin, flat pieces 3. reciprocates c. moving stairs 4. has a linear motion d. goes round and round 5. converts e. movement 6. motion f. goes in a line 7. escalator g. swings backwards and forwards 8. sheets h. goes up and down Task 8. Work in pairs. Cams are shaped pieces of metal or plastic fixed to, or part of, a rotating shaft. A “follower” is held against the cam, either by its own weight or by a spring. As the cam rotates, the follower moves. The way in which it moves and the distance it moves depends on the shape of the cam. Rotary cams are the most common type. They are used to change rotary motion into either reciprocating or oscillating motion. ……………………… Kind of motion: ……………… 35 VOCABULARY − beam (n) /biː m/ rầm, chùm (tia) − brake (n) /breɪ k/ cái hãm, cái phanh − cam (n) /kæm/ cam, bánh lệch tâm − combustion engine (n) /kəmˈ bʌ ʃ n ˈ endʒ ɪ n/ động cơ đốt trong − to compress(v) /kəmˈ pres/ nén compression (n) /kəmˈ preʃ n/ sự nén compressive (adj) /kəm´presiv/ nén compressive strength (n) độ bền nén − concrete (n, adj) /ˈ kɒ ŋkriː t/ bê tông − conjunction(n) /kənˈ dʒ ʌ ŋkʃ n/ sự kết hợp; liên từ − continent (n) /ˈ kɒ ntɪ nənt/ lục địa − to convert (v) /kənˈ vɜ ː t/ đổi, biến đổi − crankshaft (n) /ˈ kræŋkʃ ɑ ː ft/ trục khuỷu − to deliver (v) /dɪ ˈ lɪ və(r)/ phân phát; giao − die (n) /daɪ / khuôn kéo sợi − directly (adv) /dɪ 'rektli/ trực tiếp − indirectly (adv) /,ɪ ndɪ 'rektli/ gián tiếp − edge (n) /edʒ / cạnh, lề − escalator (n) /ˈ eskəleɪ tə(r)/ thang cuốn − essential (adj) /ɪ ˈ senʃ l/ cần thiết, thiết yếu − force (n) /fɔ ː s/ lực − function (n) /ˈ fʌ ŋkʃ n/ chức năng − hindrance (n) /ˈ hɪ ndrəns/ sự cản trở − line (n) /laɪ n/ dòng, đường thẳng linear (adj) /ˈ lɪ niə(r)/ thẳng, tịnh tiến, tuyến tính − lever (n) /'li:və/ cái đòn bẩy, cần gạt − mechanism (n) /ˈ mekənɪ zəm/ máy móc, cơ cấu 36 − motion (n) /ˈ məʊ ʃ n/ sự vận động, sự chuyển động − move (v) /mu:v/ chuyển động, di chuyển movement (n) /'mu:vmənt/ sự vận động; sự cử động − nuisance (n) /'nju:sns/ nguy hại − to oscillate (v) /ˈ ɒ sɪ leɪ t/ dao động oscillation (n) /,ɒ sɪ 'leɪ ∫n/ sự dao động − panel (n) /ˈ pænl/ pa-nô; bảng − car body panel (n) thân xe − pendulum (n) /ˈ pendjələm/ con lắc, quả lắc − pipe (n) /paɪ p/ ống − piston (n) /ˈ pɪ stən/ pít-tông − pump (n) /pʌ mp/ bơm − puncher (n) /ˈ pʌ nt∫ə(r)/ dụng cụ bấm lỗ, đột lỗ − to reciprocate(v) /rɪ ˈ sɪ prəkeɪ t/ chuyển động qua lại reciprocation (n) /rɪ ,sɪ prə'keɪ ∫n/ sự chuyển động qua lại − rod (n) /rɒ d/ thanh, cần, thanh kéo, tay đòn − role (n) /rəʊ l/ vai trò − to play a vital role đóng vai trò quan trọng − roller (n) /ˈ rəʊ lə(r)/ trục lăn, con lăn − rotate (v) /rou'teɪ t/ làm quay, làm xoay quanh rotation (n) /rou'teɪ ∫n/ sự quay, sự xoay vòng rotary (adj) /ˈ rəʊ təri/ quay rotor (n) /'routə/ rô-to, cánh quạt − scissors (n) /'sɪ zəz/ cái kéo a pair of scissors một cái kéo − sheet (n) /ʃ iː t/ lá, tấm, phiến, tờ − switch on = turn on mở − switch off = turn off tắt 37 − tap (n) /tæp/ vòi, khoá (nước) − tension (n) /ˈ tenʃ n/ sức ép, áp lực; ứng suất tensile (adj) /ˈ ten.saɪ l/ bị kéo, chịu kéo tensile strength (n) độ bền kéo − to trim (v) /trɪ m/ cắt trimmer (n) /ˈ trɪ mə(r)/ máy xén − wheel (n) /wiː l/ bánh xe − wrench (n) /rent∫/ chìa vặn đai ốc; cờ lê REVIEW Choose the best answer for the following sentences. 1. Mechanisms are an important __________ of everyday life. They allow us to do simple things like switch on lights, turn taps, and open doors. A. system B. partly C. part D. role 2. Mechanisms also make it possible to use __________ and lifts, travel in cars, and fly from continent to continent. A. escalators B. motors C. insulators D. contacts 3. Mechanisms provide the __________ to press steel sheets into car body panels, to lift large component from place to place, to force plastic through die to make pipes. A. processes B. things C. forces D. systems 4. All mechanisms ___________ some kind of motion. The four basic kinds of motion are rotary, oscillating, linear and reciprocating. A. revolve B. preserve C. involve D. conserve 5. A __________ converts the reciprocating motion of piston into the rotary motion. A. cam B. crankshaft C. driveshaft D. piston 6. Choosing the right lubricant is essential to reduce __________. A. friction B. mass C. cost D. weight 38 7. Mechanisms deliver the __________ to do work so they play a vital role industry. A. electricity B. power C. system D. method 8. Friction is sometimes a help but it is often a ___________. A. force B. gravity C. buoyancy D. hindrance 9. Oscillating means __________. A. swing backwards and forwards B. moving up and down C. going around and around D. going in a line 10. The foot pump is a class 2 lever since the load is between the effort and the __________. A. fulcrum B. cam C. crankshaft D. lever Translate into Vietnamese MECHANISMS The word mechanism came into the English language in the 17th century by way of the Latin word mechanismus, which traces back to the Greek word mekhane, meaning “device” or “means” together with their relation during working process. Mechanism still carries with it the meaning of “device” and can be used to describe a machine. Nowadays, it also is used to describe a way or process for getting something done in the social areas, such as “a mechanism for generating revenue” or “a crisis-resolution mechanism.” Translate into English Cơ cấu là một hoặc một số bộ phận của máy nhằm thực hiện các nhiệm vụ cơ khí như nâng và vận chuyển các đồ vật và đối tượng. Chúng hiện diện trong hầu hết các thiết bị trong nhà máy, bệnh viện, trường học, nhà ở, văn phòng… Các chuyển động của cơ cấu bao gồm chuyển động quay, chuyển động thẳng, hoặc/và chuyển động đã được lập trình. Các cơ cấu ngày càng được phát triển và được mô-đun hóa nhằm thực hiện những nhiệm vụ phức tạp, nặng nhọc, nguy hiểm cho con người và giảm chi phí sản xuất. 39 Unit 4 FORCES IN ENGINEERING Task 1. Warm-up Work in groups 1. Define what a force is. 2. Identify forces acting on the car and the airplane below. Driving force / Weight / Air resistance / Friction / Reaction forceLift / Weight / Drag / Thrust Task 2. Working in your group, try to explain these problems. 1. Why doesn't the ship sink? 2. What makes the spring stretch and what keeps the weight up? 41 3. Why doesn't the box slide down the slope? Reading 1 Predicting As you have learnt in Unit 1, it is important to think about what you are going to read in advance. Do not start to read a text immediately. One way that supports your reading is to think about the words which might appear in the text. The title might help to focus your thoughts. Which words might appear in a text with the title Forces in engineering? Task 3. You are going to read “Forces in engineering”. Here are some of the words in the reading. Can you explain the link between each word and the title? weight buoyancy equilibrium elasticity magnitude resultant newton gravity Task 4. Now read the text to check your explanations are appropriate in Task 2. Forces in engineering To solve the ship problem, we must look at the forces on the ship (Fig. 4.1). The weight, W, acts downwards. That is the gravity force. The buoyancy force, B, acts upwards. Since the ship is in equilibrium, the resultant force is zero, so the magnitudes of B and W must be the same. 42 Figure 4.1 5 Another very important force in engineering is the one caused by elasticity. A good example of this is a spring. Springs exert more force the more they are stretched. This property provides a way of measuring force. A spring balance can be calibrated in newtons, the unit of force. The block in Fig. 4.2 has a weight of 10 newtons. The weight on the balance pulls the spring down. To give equilibrium, the spring pulls up to oppose that weight. This upward force, F1, equals the weight of the block, W. Figure 4.2 10 It is important to get the distinction between mass and weight absolutely clear. Mass is the quantity of matter in an object. Weight is the force on that object due to gravity. Mass is measured in kilograms, whereas weight, being a force, is measured in newtons. 15 We have looked at buoyancy, elasticity, and gravity. There is the fourth force important in engineering, That is friction. Friction is a help in some circumstances but a hindrance in others. Let us examine the forces on the box (Fig. 4.3). Firstly, there is its weight, W, the gravity force, then there is the reaction, R, normal to the plane. R and W have a 43 resultant force trying to pull the box down the slope. It is the friction force, F, acting up the slope that stops it sliding down. Figure 4.3 Reading 2: Grammar links in texts One of the ways in which sentences in a text are held together is by grammar links. In this extract, note how each expression in italics links with an earlier expression. Another very important force in engineering is the one caused by elasticity. A spring is an example. Springs exert more force the more they are stretched. This property provides a way of measuring force. Sometimes these links cause problems for readers because they cannot put the right words in different parts of a text. Study these common grammar links: 1. A repeated noun becomes a pronoun. Springs 🡪 they 2. A word replaces an earlier expression. Force in engineering 🡪 one 3. A word replaces a whole sentence or clause. Springs exert more force the more they are stretched 🡪 This property Language study: The Present Passive To be + V3/ Past participle Study these instructions for a simple experiment on friction. 44 Figure 4.4 1. Place a block of wood on a flat surface. 2. Attach a spring balance to one end of the block. 3. Apply a gradually increasing force to the balance. 4. Note the force at which the block just begins to move. 5. Pull the block along so that it moves at a steady speed. 6. Note the force required to maintain movement. 7. Compare the two forces. Task 5. Complete this description of the experiment by using the present passive. A block of wood 1_________ on a flat surface. A spring balance 2_________ to one end of the block. A gradually increasing force 3__________ to the balance. The force at which the block just begins to move 4__________. The block 5__________ along at a steady speed. The force required to maintain movement 6__________. The two force 7_________. It is found that the first force is greater than the second. Task 6. What are the words in italics replaced? Point them out. Friction in machines is destructive and wasteful. It causes the moving parts to wear and it produces heat where it is not wanted. Engineers reduce friction by using very highly polished materials and by lubricating their surfaces with oil and grease. They also use ball bearings and roller bearings because rolling objects cause less friction than sliding ones. Language study. Usage of “It is…” 1. It is used to give opinions in an impersonal way. It is + Adj … 45 It is difficult to operate this machine. It is vital to follow safety regulations. Translate into English Thật là tiện lợi khi sử dụng remote. ……………………………............. Thật là dễ chịu/mát mẻ khi có máy điều hòa. …………………………………….. Sẽ nhanh hơn khi sử dụng ô tô thay vì xe máy. ……………………………………………….. 2. It is used to emphasize any part of a sentence. It is + Noun that/who It is friction force that stops the box sliding down. It is the mechanism that delivers the power to do the work. Translate into English Chính là Jack, người đã sửa máy in, máy scan và máy photocopy trong văn phòng. ……………………………………………………………… Chính là bạn Nam, người đã đoạt giải “Sinh viên của năm”. ………………………………………………………………….. 3. It is used in passive when the speaker wants to maintain objective view. It is + V-ed/ V3 that … It is found that the accident was due to the driver’s carelessness. It is known that the Earth rotates around the Sun. Translate into English Người ta nói rằng Việt Nam có một lịch sử lâu đời. ………………………………………….…………………….. Người ta tin rằng bức tranh ấy được vẽ bởi Leonard De Vinci. ………………………………………………………………… 46 Người ta đồn rằng trong ngôi nhà ấy có ma. ………………………………………………..……………….. Người ta chứng minh được là nước sôi ở 100oC. ………………………………………………………..……….. Task 7. Vocabulary Enlargement Forces in Engineering: bending shear compression contraction expansion Friction centrifugal force pressure tension torsion/torque REVIEW 1. Match the diagrams with (a) the names of the forces and (b) their descriptions. (a) bending, compression, shear, tension, torsion (b) squeezing or pressing together; sliding in opposite directions; stretching or pulling apart; twisting; squeezing on side + stretching the other side. A group of verbs contain the meaning of “cause something to happen” . They have the suffix ‘-en’. For example strengthen (= to cause something to be stronger). 47 Here is a list: harden - soften; lengthen - shorten; lighten - darken; strengthen - weaken; tighten - loosen; widen - flatten; sharpen - straighten. 2. Replace the phrases in italics with phrases by using verbs from the above list. Example: The torsion forces in the storm must have made the bridge weaker/ weakened the bridge. 1) The purpose of adding carbon to steel is to make it stronger. 2) Long ago, humans used stones to make their knife blades sharper and straighter. 3) In forging, metal is heated to make it softer. Then it is put in water to make it hard again. 4) Hot weather makes railway lines longer and cold weather makes them shorter. 5) If the race has made the bike saddle looser, you should make it tight with a spanner. 3. Fill in the gaps. The aim of the rigidity test is (1)…..…… (discover/to discover) if a material (2)……………… (deform/deforms) or (3)……………… (breaking/breaks) when it (4)………...…. (is bending/is bent) by a force. One end of the material (5)……..…. (secures/is secured) in the clamp, so that the material (6)………..….. (hold/is held) horizontally with one end 48 free. A weight (7)…………….. (attaches/is attached) to the free end, and then the load (8)…………… (is increasing/is increased) by adding more weights. The breaking point (9)………..…….. (measures/is measured). This (10)………………… (show/shows) us the rigidity of the material. 4. Work in groups: Discuss these questions about the three car tests below. ∙ What is the purpose of each tested? ∙ Which parts of the car are tested? ∙ What properties are tested? ∙ What is the procedure for each test? How is each test done? ∙ How does a car pass the test? What is a good result for the car? ∙ If a car fails a test, what will you recommend? VOCABULARY − absolute (adj) /'æbsəlu:t/ tuyệt đối, hoàn toàn absolutely (adv) /'æbsəlu:tli/ tuyệt đối, hoàn toàn − balance (n) /ˈ bæləns/ sự cân bằng 49 − to bend (v) /bend/ uốn cong, làm cong bend (n) /bend/ lực uốn − to buoy (v) /bɔ ɪ / đặt phao buoyancy (n) /ˈ bɔ ɪ ənsi/ sự nổi; sức nổi − block (n) /blɔ k/ khối, tảng − to calibrate (v) /'kælɪ breɪ t/ kiểm tra − centrifugal (adj) /ˌ sentrɪ ˈ fjuː ɡ l/ ly tâm − circumstance (n) /'sɜ ː kəmstəns/ hoàn cảnh, trường hợp − to contract (v) /kənˈ trækt/ co lại contraction (n) /kənˈ trækʃ n/ sự co rút − distinction (n) /dɪ ˈ stɪ ŋkʃ n/ sự khác biệt hoặc tương phản − to drag (v) /dræɡ / kéo drag (n) /dræɡ / lực cản − to destroy (v) /dɪ 'strɔ ɪ / phá hoại, phá hủy destruction (n) /dɪ s'trʌ k∫n/ sự phá hoại, sự phá hủy destructive (adj) /dɪ 'strʌ ktɪ v/ phá hoại, phá hủy − elastic (adj) /ɪ 'læstɪ k/ co giãn, đàn hồi elasticity (n) /iː læˈ stɪ səti/ đàn hồi − to equal (v) /'i:kwəl/ bằng nhau equality (n) /ɪ 'kwɔ lɪ ti/ trạng thái bằng nhau equally (adv) /'i:kwəli/ bằng nhau, đều nhau − equilibrium (n) /ˌ iː kwɪ ˈ lɪ briəm/ trạng thái cân bằng − to examine (v) /ɪ g'zæmɪ n/ khảo sát; nghiên cứu − to exert (v) / ɪ ɡ ˈ zɜ ː t / tác dụng − to act (v) /ækt/ tác dụng − to apply (v) /ə'plaɪ / tác dụng − to expand (v) /ɪ ksˈ pænd/ giãn nở expansion (n) /ɪ ksˈ pænʃ n/ sự giãn, sự nở 50 − force (n) /fɔ ː s/ lực − friction (n) /ˈ frɪ kʃ n/ lực ma sát − gradually (adv) /ˈ ɡ rædʒ uəli/ dần dần, từ từ − gravity (n) /ˈ ɡ rævəti/ trọng lực − magnitude (n) /'mægnɪ tju:d/ độ lớn, lượng − matter (n) /ˈ mætə(r)/ vật chất − to measure (v) /ˈ meʒ ə(r)/ ước lượng, đo lường − to oppose (v) /əˈ pəʊ z/ chống đối, chống lại − pressure (n) /ˈ preʃ ə(r)/ sức ép, áp suất, áp lực − property (n) /ˈ prɒ pəti/ thuộc tính; đặc tính − to pull (v) /pʊ l/ lôi, kéo − quantity (n) /ˈ kwɒ ntəti/ lượng, số lượng − reaction (n) /riˈ ækʃ n/ sự phản ứng lại, phản lực − resultant (a) /rɪ ˈ zʌ ltənt/ hợp (lực) result (n) /ri'zʌ lt/ kết quả − relative (adj) /'relətiv/ tương đối − shear (n) /ʃ ɪ ə(r)/ sự trượt, sự dịch chuyển − to sink (v) /sɪ ŋk/ chìm − to slide (v) /slaɪ d/ trượt − spring (n) /sprɪ ŋ/ lò xo − to solve (v) /sɔ lv/ giải quyết solution (n) /sə'lu:∫n/ sự giải quyết; giải pháp − steady (adj) /ˈ stedi/ đều đều; không thay đổi − to stretch (v) /stretʃ / giãn ra, rộng ra; co giãn − to thrust (v) /θrʌ st/ đẩy, ấn mạnh thrust (n) /θrʌ st/ lực đẩy − torque (n) /tɔ ː k/ mô-men xoắn, mô-men quay 51 Translate into Vietnamese FORCES Forces are any physical influence or power trying to change the movement of moving parts or the shape of objects. The change may be an either acceleration or deceleration of speeds and even from stationary state, change the direction. It may also be deforming machine parts or cutting materials. They can be applied loads or reaction forces. In engineering, they are described as vectors, so they have origins, directions and magnitudes. Translate into English Lực tác dụng từ bên ngoài vật thể có thể được chia làm bốn loại thông dụng theo phương tác dụng, bao gồm lực kéo, lực nén, lực uốn và lực cắt xoắn. Chúng gây ra phản lực hoắc ứng suất kéo, ứng suất nén, ứng suất uốn và ứng suất cắt (còn gọi là ứng suất tiếp tuyến) trong vật liệu. Ngoài ra, lực tác dụng theo chu kỳ sẽ gây ra ứng suất mỏi, hư hỏng mỏi và hiện tượng dão trong vật liệu. Hư hỏng này xảy ra ngay cả khi ứng suất mỏi là nhỏ so với ứng suất đàn hồi. 52 Unit 5 WASHING MACHINE Task 1. Warm-up What devices in your home operate automatically? List them all. In your opinion, why can they operate like that? Task 2. List some of the factors the control system of a washing machine must handle. This diagram may help you. Figure 5.1. Washing machine Reading: Reading diagrams In engineering, diagrams carry a great deal of information. They can also help you to understand the accompanying text. For this reason, it is helpful to try to understand the diagram provided before reading the text. 53 Task 3. Study the diagram again. Match the items with their proper functions. Items Functions 1 Pump 2 Motor 3 Shock absorber 4 Solenoid valves 5 Heater 6 Pressure sensor 7 Door lock and sensor 8 Temperature sensor 9 Fan a. Measures the water temperature and reports it to the control unit b. Cools the pump motor c. Controls the flow of water into the machine d. Senses when the drum is full of water and reports it to the control unit e. Pumps water out of the drum f. Rotates the drum g. Absorbs the shock of the spinning drum when loaded h. Senses whether the door is open or shut and reports it to the control unit i. Raises the temperature of the water Task 4. Read this text to check your answers to Task 2. Control systems in the home Most devices in the home have some sort of control. For example, you can control the volume of a TV by using a remote control. The building blocks of a control system are: Input Control Output Press button on remote control Signal is sent to TV Volume is adjusted 5 The input can be any movement or any change in the environment. For example, a drop in temperature may cause a heating system to come on. The control may change the size of the output (for example, adjusting the sound of a TV). Often this involves changing one kind of input into different kind of output. For example, opening a window may set off a burglar alarm. The outputs can be of many kinds. An alarm system may ring a 10 bell, flash lights, and send a telephone message to the police. 54 Most control systems are closed loops. That means they incorporate a way of checking that the output is correct. In other words, they have feedback. The thermostat in a central heating system (Fig. 5.2) provides constant feedback to the control unit. Temperature sensor Control unit Boiler switch Boiler/Pump Radiators Feedback Figure 5.2. Closed loop The control system of a modern washing machine has to take into 15 account several different factors. These are door position, water level, water temperature, wash and spin time, and drum speeds. Most of them are decided when you select which washing program to use. Fig. 5.3 shows a block diagram of a washing machine control system. 20 You can see that this is quite a complex closed loop system using feedback to keep a check on water level, water temperature, and drum speeds. Clock Water level sensor Door position sensor Water temp. sensor Drum speed sensor Program selector sector Control unit Feedback Feedback Feedback Pump Water valves Heater Motor Figure 5.3. Modern control system 55 The control unit is the heart of the system. It receives and sends out signals which control all the activities of the machine. It is also capable of diagnosing faults which may occur, stopping the program, and informing the service engineer what is wrong. It is a small, dedicated computer which, like other computers, uses the language of logic. Task 5. Answer these questions. 1. What are elements of the building blocks of a control system? 2. What are inputs and outputs? 3. What is a closed loop? Find out closed loops in Fig 6.3, then redraw them. 4. Explain how a control system operates. Task 6. Read the following text to find the answers to these questions. 1. What devices are used to lock the door? 2. What provides feedback to the control unit about the door position? Text 1: Door position The machine will not start any program unless the door is fully closed and locked. When the door is closed, it completes an electrical circuit which heats up a heat-sensitive pellet. This expands as it gets hot, pushing a mechanical lock into place and closing a switch. The switch signals the control unit that the door is closed and locked. Only when it has received this signal will the control unit start the wash program. Complete your section of the table below. Then exchange information with your partner to complete the whole table. Control factor Operating device Feedback by 1 Door position heat-sensitive pellet Switch 2 Water level ……………..…………………… ……………..…… ……………… 3 Water temperature ……………..…………………… ……………..…… ……………… 4 Wash and spin time ……………..…………………… ……………..…… ……………… 5 Drum speed ……………..…………………… ……………..…… ……………… 56 Text 2: Water level When a wash program first starts, it has to open the valves which 5 allow the water in. There are usually two of these valves, one for hot water and one for cold. Each must be controlled separately depending on the water temperature needed for that program. The valves are solenoid operated, i.e. they are opened and closed electrically. The rising water level is checked by the water level sensor. This is a pressure sensor. The pressure of the air in the plastic tube rises as it is compressed by the rising water. The pressure sensor keeps the control unit informed of the pressure reached and the control unit uses the information to decide when to close the water inlet valves. Text 3: Water temperature The temperature sensor, a type of thermometer which fits inside the 5 washer drum, measures the water temperature and signals it to the control unit. The control unit compares it with the temperature needed for the program being used. If the water temperature is too low, the control unit will switch on the heater. The temperature sensor continues to check the temperature and keeps the control unit informed. Once the correct temperature is reached, the control unit switches off the heater and moves on to the next stage of the program. Text 4: Clock The control unit includes a memory which tells it how long each stage of a program should last. The time may be different for each program. The electronic clock built into the control unit keeps the memory of the control unit informed so that each stage of each program is timed correctly. Text 5: Drum speed During the washing and spinning cycles of the program, the drum 5 has to spin at various speeds. Most machines use three different speeds: 53 rpm for washing; 83 rpm for distributing the load before spinning; 100 rpm for spinning. The control unit signals the motor to produce these speeds. The motor starts up slowly, then gradually increases speed. The speed sensor, a tachogenerator, keeps the control unit informed of the speed that has been reached. The control unit uses the information to control the power of the motor and so controls the speed of the drum at all times. 57 Language study: If/ Unless Task 7. Fill in the blanks in this table using the information in Fig 5.3 and the texts in Task 6. Sensor Condition Control unit action Waterlevel low open inlet valves level high enough Water temperatureswitch on heater high enough Drum speeddecrease motor speed The conditions which the sensors report determine the actions of the control unit. We can link each condition and action like this: If the water level is low, the inlet valves are opened. Task 8. Write similar sentences for the other five conditions given above. Now study this example: Sensor Condition Control unit action Door Door open Machine cannot start Door closed Machine can start We can link these conditions and actions as follow: 1. If the door is open, the machine cannot start. 2. If the door is closed, the machine can start. 3. Unless the door is closed, the machine cannot start. We use unless when an action cannot or will not happen if a prior condition is not true. In example 3, Unless means If … not. We can rewrite 3 as: If the door is not closed, the machine cannot start. 58 Task 9. Complete these sentences using Unless and your knowledge of engineering. 1. Unless the ignition is switched on, a car cannot _________. 2. Unless the pilot light is on, gas central heating will not __________. 3. Unless the diverter valves are switched to central heating, the radiators will not __________. 4. Unless there is current flowing in the primary coil of a transformer, there will be no current in the _________ coil. 5. Unless there is __________ in the cylinders, the petrol engine will not start. 6. Unless the doors are _____________, the lift will not operate. 7. Unless mild steel is painted, it will _____________. 8. Unless electrical equipment is earthed, it may be ___________. Task 10. Connect the sentences using the word/words given. Then join all sentences you have made to build a paragraph. 1. Which The temperature sensor measures the water temperature. The temperature sensor is a type of thermometer. 2. And The temperature sensor fits inside the washer drum. The temperature sensor signals the water temperature to the control unit. 3. Which The control unit compares the water temperature with the temperature. The temperature is needed for the program being used. 4. If The water temperature is too low. The control unit will switch on the heater. 5. And The temperature sensor continues to check the temperature. The temperature sensor keeps the control unit informed. 59 6. When … and The correct temperature is reached. The control unit switches off the heater. The control unit moves on to the next stage of the program. Language study: Ability and Inability 1. Making someone able or something possible (make…able, enable, allow, permit) e.g. That database allows you to search for client names and addresses. 2. Being able or unable (be able/unable to, be capable/incapable of, can/cannot) e.g. This new monitor can display more than two million colours. Synthetic fibre is unable to replace natural fibre. 3. Making someone unable or something impossible (make…unable, stop, prevent, prohibit) e.g. Friction force stops the box sliding down. Notes: * be able/unable to do sth * be capable/incapable of doing sth/N * prohibit/stop/prevent sth/sb from doing sth/N * allow/permit/enable sth/sb to do/not to do sth * make sth/sb adj/do sth Complete the sentences a. ______________ is not permitted in the class. b. The parents protect the children from ______________. c. The machine is equipped with a control unit, thus makes it able to __________. d. The manager prohibits _____________ in the factory. 60 e. The machine has touch panel to make it ___________ in operation. f. Normal airplanes are incapable of ______________ at velocity of light. g. Modern technology is _______________ without computers. h. Door lock enables_____________ when the car moves at _____________. i. A faster processor in the computer ___________ solving complicated computations. Language study: have sth done/Adj keep sth done/Adj I have my house cleaned. I have my hair cut. I have my computer ……………………. The pressure sensor keeps the control unit informed of the pressure reached. The temperature sensor keeps the control unit informed. The machine has damaged. Please have it …………………………. The wall is dirty. I will have it …………………………. Translate into English a. Cảm biến tốc độ luôn kiểm soát vận tốc của động cơ. ……………………………………………………………………………………………………… b. GPS luôn thông báo vị trí xe hơi. ……………………………………………………………………………………………………… c. Cảnh sát luôn kiểm tra nồng độ cồn của người lái xe. ……………………………………………………………………………………………………… d. Hệ thống cảnh báo động đất luôn đo rung động của mặt đất. ……………………………………………………………………………………………………… e. Mục đích của bảo trì là bảo đảm hệ thống luôn vận hành tốt. ……………………………………………………………………………………………………… 61 Task 11. Match column A with column B to build sentences of ability and inability. A B 1. Improving quality control will enable us 2. Shortage of space prevents us from a. the storage of chemicals in plastic containers. b. carrying the volume of data required today. 3. Regulations prohibit c. see the person you are talking to. 4. A machine breakdown means that we can't d. producing more product lines. 5. Old copper cables are incapable of e. now be used to send emails. 6. Using a videophone allows you to f. to become more profitable. 7. Mobile phones can g. unauthorized users accessing a network. 8. A firewall is used to stop h. finish the order this week. Task 12. There is a mistake in each of the following sentences. Underline the mistake then correct it. 1. All unauthorized personnel are prohibited from entering this area. 2. Building regulations do not allow of the use of asbestos in public buildings. 3. Only fully qualified electricians should be permitted to repair these appliances. 4. Deep pile foundations are able to support a high building. 5. Water is unable to pass through the vapour barrier. 6. Designers can design complex structures using computer-aided design tools. 7. Scientists are not yet able to cure cancer. 8. Aspirin is known to prevent people from having a heart attack. 62 REVIEW Task 1. Matching the items inside the washing machine (picture shown) with their proper meanings. a. Mô tơ chính: Là mô tơ giúp quay lồng máy giặt b. Núm chọn chế độ giặt c. Núm kiểm soát mực nước d. Nút điểu khiển thời gian giặt e. Trục khấy: Dùng để đảo quần áo và đồ dơ trong nước, ngoài ra còn có tác dụng đẩy nước đi qua sợi vải từ trong ra ngoài f. Gối đỡ tròn g. Đường nước cấp h. Pu-li có tác dụng truyền lực cho lồng giặt i. Bộ lọc cặn j. Công tắc mất thăng bằng: Khi tải trọng máy giặt bị lệch hoặc do máy giặt lệch chân dễ gây hiện tượng mất thăng bằng. Công tắc này thiết kế để tắt máy khi xảy ra sự mất cân bằng 63 k. Van cấp nước vào l. Đường nước xả m. Thùng chứa nước: Dùng để chứa nước trong quá trình giặt n. Công tắc mức tràn o. Mức kiểm soát mực nước p. Pu-li truyền động của mô tơ q. Gối đỡ r. Đường ống nước xả s. Bơm nước xả Task 2. Match the pictures with the verbs in the box. Task 3. The photos illustrate the main stages in assembling a car, but they are in wrong order. Write the figure numbers in the correct boxes in the chart below. 64 Reading Now read this website of the car company and check your answers to Tasks 2. ASSEMBLING A CAR First, the parts are delivered by truck or rail to the delivery area of the car assembly plant. From here, some parts are taken to the body shop, and other parts are transported to the chassis line. The parts are carried around the plant by forklift trucks or conveyor belts. In the body shop, the panels are welded to the frame to form the body of the car. This is done by more than 400 robots. Then the body is taken to the paint shop. Here it is cleaned and painted by robots. Special clothing is worn by the robots to project the paint. After this, the body is checked by human workers to look for faults. Next, the painted body moves along a conveyor belt to the trim 65 line and many parts are added to it. For example, the instrument panel, the air conditioning system, the heating system and the electrical wiring are all installed here. The windscreen is inserted by robots using laser guides. Meanwhile, in the chassis, in the line, components are added to the chassis. First, the chasis is turned upside down to make the work easier. Then the fuel system, the axles and the drive shaft are all installed. Next the chassis is turned over (rightside up). The engine is lowered into the chassis and connected to it. Now, the chassis and the body move simultaneously to the final assembly line. Here the body is attached to the chassis, and all the final parts are added. The tyres and the radiator are added here. The hoses are connected, and the radiator and air conditioner are filled with fluid. The central computer of the car is also installed here. Lastly, the finished car and all electrical systems are tested. The car is filled with fuel and the engine is started for the first time. The car is put on special rollers to test the engine and the wheels. If it passes the test, the car is finally driven out of the assembly plant. Task 4. Form Adjectives from the proper suffixes below. -ful -ic -ous -y -ant -al -able -ial -ive -ible -ent danger dirt magnet rely origin experiment wash flex expense excel resist use industry Task 5. Complete the following sentences with the adjectives and adverbs in brackets. Use each word only once. 1. The system will shut down______________. There is an ___________temperature control. (automatic/automatically) 2. New testing methods have made the process much more _______________. Quality control runs more____________. (efficient/efficiently) 3. Our aim is to ensure ____________operation at the plant. The manufacturing process should run _________. (smooth/smoothly) 4. Demand for electricity is ___________ lower in the evening. Statistics show that there is a ___________ fall in demand after 10 p.m. (general/generally) 66 5. People are becoming more interested in _____________ friendly products. There is a growing interest in _____________ issues. (environmental/environmentally) 6. Safety procedures must be __________observed to avoid accidents. The manager in coal mine must be __________ about activities underground. (strict/strictly) Task 6. Here is a part of a presentation on the textile industry in the UK. Tick the correct words. The number of people who work in the textile (a) manufactured/manufacturing industry in the UK has fallen (b) considerable/considerably over the last 50 years. Today, it employs (c) approximate/approximately 130,000 people. Textiles for clothing and carpets have always been (d) important/importantly but today there is (e) increasing/increasingly trade in fabrics for (f) industrial/ industrially applications. Fabrics are used (g) increasing/increasingly in the healthcare and automotive industries. The export of wool and (h) woolen/ wool products has remained fairly (i) constant/constantly over the last 15 years. The UK also has a (j) significant/significantly silk industry, which produces over 170 million worth of goods (k) annual/annually. The UK linen trade has an (l) excellent/excellently reputation for quality and service and British exports remain very (m) healthy/healthily. The UK’s expertise in chemistry is (n) extensive/ extensively and this is (o) important/importantly to the (p) dyed/dying industry. The manufacturing of dyestuffs is (q) relative/relatively strong. The sale of carpets contributes to the sale of the textile (r) significant/significantly. The carpet industry has (s) particular/ particularly strengths in the (t) high/highly quality end of the market. a_manufacturing_ b ____________ c ____________ d ____________ e ______________ f ______________ g ____________ h ____________ g ______________ h ______________i _____________ k ___________ l ______________ m _____________ n ____________ o ____________ p ______________ r ______________ s ____________ t ____________ 67 Translate into Vietnamese A washing machine, sometimes called laundry machine, clothes washer or washer, is a machine used to wash laundry, such as clothing, carpet and sheets. In most cases, the machines use water and detergent. Modern washing machines may use dry cleaning techniques (which uses alternative cleaning fluids, and is performed by specialist businesses) or ultrasonic cleaners. (Source: Mintz, Steven, “Housework in Late 19th Century America”, Digital History.) Translate into English Ngày nay, máy giặt là thiết bị không thể thiếu trong các ứng dụng trong gia đình cũng như trong công nghiệp. Nó giúp chúng ta giặt giũ quần áo, ra trải giường và thảm trong nhà hàng ngày, đồng phục trong nhà máy, văn phòng, bệnh viện… Tại các quốc gia lạnh, nước nóng được sử dụng một cách hiệu quả cho máy giặt thay vì nước lạnh như ở các quốc gia nhiệt đới. VOCABULARY - to absorb (v) /əbˈsɔ:b/ hấp thu absorption coefficient /əbˈsɔ:bʃn kouiˈfiʃnt/ hệ số hấp thu - to sense (v) /sens/ cảm nhận, hiểu, cảm biến sensor (n) /ˈsensə/ cảm biến - to adjust (v) /əˈdʒʌst/ điều chỉnh - to flash (v) /flæʃ/ chớp - loop (n) /lu:p/ vòng lặp, chu trình - detergent (n) /diˈtə:dʒənt/ chất tẩy, xà bông - to incorporate (v) /inˈkɔ:pərit/ liên kết, liên hợp - to take into account đưa vào tính toán, tính tới - to diagnose(v) /ˈdaiəgnouz/ chẩn đoán - pellet (n) /ˈpelit/ viên, thanh, hạt - solenoid valve (n) /ˈsoulənɔid/ van điện từ 68 - tachogenerator (n)/ˈtækədʒenəreitə(r)/ bộ phát xung - agitator (n) /ˈædʒiteitə/ trục khuấy, bộ phận khuấy to agitate (v) /ˈædʒiteit/ khuấy - pulley (n) /ˈpuli/ pu-li - to transmit (v) /trænzˈmit/ truyền, truyền động - lid (n) /lid/ nắp, vung, mũ - chassis (n) /ˈtʃæsi/ khung gầm (xe) - to convey (v) /kənˈvei/ vận chuyển, tải - hose (n) /houz/ ống dẫn (mềm) - plant (n) /plænt/ xưởng, dự án, công trình 69 Unit 6 ROBOTICS Figure 6.1. Robots Task 1. Warm-up Try to write a definition of robots. Compare with your classmates. Reading 1 Revising skills In the tasks below, we will revise some reading skills you have studied. Task 2. The diagram below shows the 3 components of an industrial robot. What are their functions? Figure 6.2. The components of an industrial robot 71 Task 3. Now read this text to check your answers to Task 2. The manipulator This is the bit which actually does the mechanical work, and in this case it is anthropomorphic (i.e. of human-like form), resembling an arm. The power supply For heavy-duty hydraulic or pneumatic machines this will be a compressor. In smaller, lightweight versions which use electrical stepper motors rather than hydraulics or pneumatics, this would be omitted. The computer The controlling computer is fitted with appropriate interfaces. These may include digital inputs, digital outputs, ADCs (analogue-to-digital converters), DACs (digital-to-analogue converters), or stepper motor control ports. These control the various compressors, stepper motors, and solenoids, and receive the signals from the manipulator’s sensors. Task 4. In your opinion, can robots replace human completely? Students make pairs or groups of three or four, and then discuss it. Task 5. Read the following text to find the answers to these questions. 1. What is the work volume of a manipulator? 2. Why is the work volume of a human greater than that of an industrial robot? 3. What are ‘degrees of freedom’? Work volume Robots are multifunctional so an important design issue for the manipulator is its ‘work volume’: the volume of space into which it can be positioned. The greater the work volume, the more extensive the range of tasks it can be programmed to carry out. As a human being, your work volume consists of all the places 5 your hands can reach. Most industrial robots have a much more limited work volume because they are bolted to the floor. Even with the same limitation applied, however, the human body is a very flexible machine with a work volume described – very approximately – by a cylinder about 2.2 m high with a radius about 1.8 m and a domed top. 72 Degrees of freedom 10 In order to achieve flexibility of motion within a three-dimensional space, a robot manipulator needs to be able to move in at least three dimensions. The technical jargon is that it requires at least three ‘degrees of freedom’. Figs. 6.3 a-d show a number of the more common types of robot manipulator mechanisms. Each has the requisite three degrees of freedom, allowing either linear or rotational movement. Reading 2 Transferring information Task 6. Study the text and the diagram (Fig. 6.3a) below and note how the information has been transferred to Table 1. Fig. Types Degrees of freedom Work volume Linear Rotational 6.3a Cartesian or rectilinear 3 0 Cube Common types of manipulator Fig. 6.3a is the simplest. Its three degrees of freedom are all linear and at right angles to each other, so they correspond to the three Cartesian co-ordinates. Driving it presents no mathematical difficulties, since each degree of freedom controls a single Cartesian co-ordinate without affecting the others. Fairly obviously, the work volume of the Cartesian manipulator is a cube. Figure 6.3a. Cartesian or rectilinear manipulator 73 Task 7. Work in groups of three. Your teacher will select a text for you. Read the text and the diagram to complete your section of Table 1. Text 1 The second type of manipulator, shown in Fig. 6.3b, is called a cylindrical manipulator because of the shape of its work volume. It has one rotational and two linear degrees of freedom. Because of the rotational aspect, however, the maths needed to position it becomes more involved, which means that for a given response speed a faster processor is necessary. Figure 6.3b. Cylindrical or post-type manipulator Fig. Types Degrees of freedom Work volume Linear Rotational 6.3b Text 2 Fig. 6.3c shows the spherical manipulator which has two rotational and one linear degrees of freedom. The work volume is indeed a sphere, and once again the complexity of positioning the device increases. Figure 6.3c. Spherical or polar manipulator Fig. Types Degrees of freedom Work volume Linear Rotational 6.3c 74 Text 3 5 The final type of manipulator has three rotational degrees of freedom. This is the most complex type to control, but it has increased flexibility. Fig. 6.3d shows this type of manipulator – the anthropomorphic arm. The work volume of a practical manipulator of this form is shown in Fig. 6.4. You will notice that it is basically spherical but has missing portions due to the presence of the arm itself and because the rotations cannot achieve a full 360 degrees. The scallops on the inner surface are caused by constraints imposed by the joints. Figure 6.3d. Anthropomorphic or joint manipulator Figure 6.4. Working volume of anthropomorphic manipulator Fig. Types Degrees of freedom Work volume Linear Rotational 6.3d 75 Structure: “In order to…” In order to achieve flexibility of motion within a three-dimensional space, a robot manipulator needs to be able to move in at least three dimensions. to / in order to + V.inf for + Gerund (V.ing)/ N To pass the examination, students must study hard. For higher examination scores, students must study hard. Complete the sentences 1. …………………….…………………………, the youth must have good health. 2. To become a famous physician, you ………............................experiments. 3. …………………….……………………………………….., the teachers work hard. 4. …………………………a good swimmer, you ………………………every day. 5. To produce an advanced material, ………………………………………………. 6. ……………………………………………………………….. for a good job. 7. …………………………………… a good singer, ……………………………………… Task 8. Complete the blanks in this text. Mechanical wrist It is worth pointing 1__________ that a human arm has far more freedom 2_________ the minimum three degrees of freedom, giving very great flexibility in terms 3___________ positioning, path taken, and angle of approach. Even without a wrist, the redundant degrees of freedom of the 4__________ body would allow you to carry out most normal operations. Any of the basic manipulators shown 5_________ Figs. 6.3 a-d, on the other 6__________, would be virtually useless as they stand. Although they could get to any position, they 7__________ only approach objects from a single angle. To take an 8__________, removing a screw would be impossible 9__________ the manipulator could not align a screwdriver to fit the screw properly. Even if it was able to, it still would 10___________ be possible to carry out the necessary rotating action. 76 A wrist is therefore added to most basic manipulators to 11___________ the required mechanical flexibility to 12__________ real jobs. In general, for total flexibility the wrist itself requires three degrees of freedom, thereby bringing the grand total up to six. The 13____________ common type of wrist has two bending and one rotational degrees of freedom. Fig. 6.5 shows this type of mechanical wrist. Figure 6.5. Wrist mechanism Task 9. Technical reading: Stepper motors Read the following text to find the answers to these questions, and then complete the table. 1. Why do you use a stepper motor to position the head of a disk drive unit? 2. Name two components that are present in other electric motor types but absent from stepper motors. 3. For accuracy in positioning, do you select a stepper motor with a large or a small step angle? Stepper motors are useful wherever accurate control of movement is required. They are used extensively in robotics and in printers, plotters and computer disk drives, all of which require precise positioning or speed. In a plotter, for example, by using two motors running at 90 degrees to each other, they can be used to drive a pen with an exact distance in all directions. In robotics, they are used to position manipulators exactly where required. A stepper motor does not run in the same way as a normal DC motor, i.e. continuously rotating. Instead, it runs in a series of measured steps. These steps are triggered by pulses from a computer, and each pulse makes the motor turn either in a forward or a reverse direction by 77 an exact interval, typically 1.8, 2.5, 3.75, 7.5, 15, or 30 degrees. Accuracy is within 3% to 5% of the last step. Figure 6.5a Figure 6.5b The rotor in a stepper motor is constructed from several permanent magnets with north and south poles. The stator is wound in a series of electromagnets, usually four, which can be switched on and off. Figs.6.5a and b illustrate the operation of a permanent magnet-type stepper motor. When current is applied to the stator coils, it creates the pole arrangement shown in Fig.6.5a. Poles 1 and 2 are north. Hence, the south pole of the rotor is attracted to both of them and settles in the mid position as shown. When the stator currents are changed to produce the pole arrangement shown in Fig.6.5b, pole 1 has south polarity. This repels the rotor which moves to the new position as shown. Each polarity change on the stator causes the rotor to move (in this case) 45 degrees. Stepper motors can be divided into two groups. The first one works without a permanent magnet. The second one has a permanent magnet, usually located on the rotor. Variable reluctance motors form the first group. As there is no permanent magnet, the variable reluctance motor has practically no detent torque. The rotor spins freely and gives good acceleration and high speed if lightly loaded. Applications include micro positioning tables. The second group comprises the permanent magnet motor, the hybrid motor, and the disc magnet motor. The permanent magnet type offers high dynamic torque at low speed and large step angles. This is a low cost motor used extensively in low inertia applications such as computer peripherals and printers. The hybrid type combines features of both types mentioned above. It has good speed/torque characteristics and micro-stepping capability. Steps of 1.8 degrees are possible. Disc magnet motors can be made very small and are very efficient. One of their first applications was in quartz controlled watches. 78 Task 10. Mind mapping Mind mapping is a useful means to make sure you understand main ideas of the reading. Complete the following diagram. 79 VOCABULARY − to achieve (v) /əˈ tʃ iː v/ đạt được, giành được − accurate (adj) /ˈ ækjʊ rət/ chính xác accuracy (n) /ˈ ækjʊ rəsi/ độ chính xác − to affect (v) /ə'fekt/ ảnh hưởng effect (n) /i'fekt/ sự ảnh hưởng − analogue (adj) /ˈ ænəlɒ ɡ / tín hiệu tương tự − anthropomorphic (adj) /ˌ ænθrəpəˈ mɔ ː fɪ k/ giống hình người − appropriate (adj) /əˈ prəʊ priət/ thích hợp − approximately (adv)/əˈ prɒ ksɪ mətli/ khoảng chừng, xấp xỉ − Cartesian (adj) /kɑːˈ tiː ziən/ (thuộc) thuyết Đề-các − to command (v) /kəˈ mɑ ː nd/ ra lệnh command (n) /kəˈ mɑ ː nd/ lệnh − compressor (n) /kəmˈ presə(r)/ máy nén − constraint (n) /kən'streint/ sự ràng buộc − to construct(v) /kənˈ strʌ kt/ chế tạo − to correspond (v) /ˌ kɒ rəˈ spɒ nd/ phù hợp; tương ứng − cube (n) /kjuː b/ hình lập phương − current (n) /ˈ kʌ rənt/ dòng điện − cylindrical (adj) /səˈ lɪ ndrɪ kl/ hình trụ − definition (n) /ˌ defɪ ˈ nɪ ʃ n/ định nghĩa − digital (adj) /ˈ dɪ dʒ ɪ tl/ kỹ thuật số digital input (n) ngõ vào số digital output (n) ngõ ra số − analogue to digital converter (n) bộ chuyển đổi tương tự - số − flexible (adj) /ˈ fleksəbl/ linh động, linh hoạt flexibility (n) /,fleksə'biliti/ tính linh hoạt, tính linh động − hydraulic (adj) /haɪ ˈ drɔ ː lɪ k/ thủy lực − hybrid (n) /ˈ haɪ .brɪ d/ lai 80 − to impose (v) /im'pouz/ áp đặt − inner (n) /'inə/ bên trong − interface (n) /ˈ ɪ ntəfeɪ s/ giao diện, cổng giao tiếp − inertia (n) /ɪ ˈ nɜ ː ʃ ə/ mô-ment quán tính tĩnh − jargon (n) /ˈ dʒ ɑ ː ɡ ən/ từ chuyên môn, thuật ngữ − joint (n) /dʒ ɔ ɪ nt/ khớp − manipulator (n) /məˈ nɪ pjuleɪ tə(r)/ tay máy − magnet (n) /ˈ mægnət/ nam châm permanent magnet (n) /ˈ pɜ ː mənənt/ nam châm vĩnh cửu − to limit (v) /'limit/ giới hạn, hạn chế limitation (n) /,limi'tei∫n/ sự hạn định, sự giới hạn − obviously (adv) /ˈ ɒ bviəsli/ rõ ràng; hiển nhiên − to omit (v) /əˈ mɪ t/ quên; bỏ qua − pneumatic (adj) /njuː ˈ mætɪ k/ làm việc nhờ khí nén − pulse (n) /pʌ ls/ xung − pole (n) /pəʊ l/ cực polarity (n) /pəʊ ˈ lærəti/ sự phân cực − to position (v) /pə'zi∫n/ xác định vị trí − rectilinear (adj) /ˌ rektɪ ˈ lɪ niə(r)/ thẳng − requisite (adj) /ˈ rekwɪ zɪ t/ cần thiết − to resemble (v) /rɪ ˈ zembl/ giống với, tương tự với − reluctance (n) /rɪ ˈ lʌ ktəns/ từ trở − robot (n) /ˈ rəʊ bɒ t/ người máy − sphere (n) /sfɪ ə(r)/ hình cầu, khối cầu, mặt cầu spherical (adj) /ˈ sferɪ kl/ có hình cầu − to trigger (v) /ˈ trɪ gər/ kích xung − torque (n) /tɔ ː k/ mô-ment xoắn detent torque (n) mô-ment hãm − volume (n) /ˈ vɒ ljuː m/ thể tích; khối lượng 81 REVIEW I. Choose the best answer. 1. The ___________does the mechanical work. It can be anthropomorphic. A. manipulator B. power supply C. degrees of freedom D. controller 2. For lightweight duty, the power supply can use ______________than hydraulics or pneumatics. A. DC motor B. stepper motor C. hydraulic motor D. all are incorrect 3. The heart of robot is the controlling computer which is fitted with _______________interfaces. A. different B. differently C. appropriate D. appropriately 4. The ____________is an important design issue for the manipulator. The greater the___________, the more tasks it can be programmed to carry out. A. work volume/manipulator B. work volume/work volume C. degrees of freedom/work volume D. degrees of freedom/manipulator 5. In order to achieve ____________ of motion within a three dimensional space, a robot manipulator needs to be able to move in at least three dimensions. A. flexible B. flexibility C. accurate D. accuracy 6. ______________is the simplest. Its three degrees of freedom are all linear and at right angles to each other. A. Cylindrical manipulator B. Spherical manipulator C. Cartesian manipulator D. Joint manipulator 7. ______________is the most complex type of manipulator. A. Cylindrical manipulator B. Spherical manipulator C. Cartesian manipulator D. Joint manipulator 8. _____________has one rotational and two linear degrees of freedom. A. Cylindrical manipulator B. Spherical manipulator C. Cartesian manipulator D. Joint manipulator 82 9. The work volume of Cartesian manipulator is ____________. A. a cube B. a sphere C. cylinder D. all are incorrect 10. A manipulator have many joints is flexible but control is __________. A. simple B. complex C. appropriate D.implemental II/ Translate the following text into Vietnamese Robotics is the branch of mechanical engineering, electrical engineering and computer science that deals with the design, construction, operation, and application of robots, as well as computer systems for their control, sensory feedback, and information processing. These technologies deal with automated machines that can take the place of humans in dangerous environments or manufacturing processes, or resemble humans in appearance, behavior, and/or cognition. The concept of creating machines that can operate autonomously dates back to classical times, but research into the functionality and potential uses of robots did not grow substantially until the 20th century. Throughout history, robotics has been often seen to mimic human behavior, and often manage tasks in a similar fashion. Today, robotics is a rapidly growing field, as technological advances continue; researching, designing, and building new robots serve various practical purposes, whether domestically, commercially, or militarily. Many robots do jobs that are hazardous to people such as defusing bombs, mines and exploring shipwrecks. (Source: “Robotics”. Oxford Dictionaries, Retrieved 4, February 2011.) III/ Translate into English Robot là một dạng thiết bị tự động nhằm thực hiện các công việc giống nhau một cách tự động và lặp đi lặp lại. Điều này giúp làm giảm ảnh hưởng của sai sót từ con người, tăng sản lượng và độ tin cậy của sản phẩm. Robot có thể được lập trình lại nhằm tăng mức độ linh hoạt của nó trong việc sản xuất nhiều loại sản phẩm khác nhau. Kỹ thuật robot kết hợp nhiều lãnh vực khác nhau bao gồm cơ khí, điện-điện tử, kỹ thuật thủy lực-khí nén và công nghệ thông tin. 83