Standard Grade Computing

1. Standard Grade Computing Automated Systems

2. What is an Automated System • When computers are used to control a system consisting of machinery and equipment.

3. Examples of Automated Systems • washing machine • central heating system • video recorder • microwave oven • controlling machinery in a factory • traffic light control • aircraft guidance

4. Why use Automated Systems? • faster than a humans • do boring and repetitive jobs • accurate - don’t make mistakes • efficient – don’t need breaks • can be used in dangerous situations • flexible - can be programmed to do different tasks

5. Stationary Robots • Stay in one place all the time • e.g. used on factory assembly lines • Control programs are stored on disc or tape • Can be reprogrammed to do a different task

6. Anatomy of a Robot Arm • Some robots have parts that resemble human limbs • A jointed robot arm has a • waist • shoulder • elbow • wrist • hand (specialised to suit the robot’s task) Shoulder Elbow Waist Wrist

8. Degrees of Freedom • The number of degrees of freedom is the number of ways the arm can move. • To work in three dimensions the arm must have at least three degrees of freedom. • The human arm has eight degrees of freedom.

9. Degrees of Freedom ROTATE BASE OF ARM PIVOT BASE OF ARM BEND ELBOW WRIST UP AND DOWN WRIST LEFT AND RIGHT ROTATE WRIST

10. End Effectors • The ‘hand’ of the robot arm is specialised to the task the robot is programmed to do. • The ‘hand’ could be a • gripper • paint spray gun • welding electrode • suction cap • paint stripper • magnet

11. Mobile Robots • Robots which move are called mobile robots. The robot Dante walks into volcanoes. In 1994, NASA, Carnegie Mellon University and the Alaskan Volcano Observatory used satellite and Internet connections to manoeuvre Dante into the active crater of Mt. Spur, an Alaskan volcano 90 miles west of Anchorage.

12. Mobile Robots • Nomadis a four wheeled robot that has been looking for asteroids in Antarctic. • Nomad was built to explore the Antarctic in search of new meteorite samples in January 2000. • Nomad spent nearly two weeks in the Arctic frost, examining over 100 indigenous rocks and ultimately classifying seven as bona-fide meteorites.

13. Automated Guided Vehicles

14. Remote-operated Vehicles Underwater ROV’s

15. Computer Aided Design • Buildings • Cars • Motorways • Mobile Phones • Circuit Boards • Processors

16. Benefits of CAD • Easier to produce complex drawings • Making changes to design is easier • Can make multiple copies • Can use library shapes

17. CAD Hardware • High resolution monitor • Powerful processor • High capacity backing storage • Graphics tablet • Graphics plotter

18. Computer Aided Manufacture • Use of computers to control machinery in the production process • Car manufacture • Fabric cutting in making clothes • Fitting components to circuit boards

19. CADCAM • Objects are designed using CAD • Design is fed to the controlling computer • Robots and machines assemble the product

20. Benefits of CADCAM • Faster process • More accurate process • Less waste • Increases productivity • Higher quality end product

21. Effects of CADCAM • Machines have replaced people • Fewer jobs • Remaining jobs have become deskilled • More jobs for computer programmers and engineers

22. Simulation • A computer mimics a real world activity • Flying a plane • Driving a car • Crashing a car • Performing surgery • Computer games

23. Virtual Reality • The user is immersed in the computer generated world • Virtual reality headsets/helmets • Sensory gloves

24. Intelligent Robots • Have a range of sensors • Mimic the human senses and functions • Hear : microphone • See : sonar beams / optical sensors • Feel : tactile/pressure sensors • Walk : Human-like legs

25. Asimo

26. Robots in the Future • Hovering the house • Ironing

27. Control computer Open Loop Control Control Information

28. Feedback from sensor Traffic Sensor Control computer Control Information Closed Loop Control

29. Sensors • A sensor detects physical quantities e.g. heat, and provides this input to the controlling computer.

30. Types of Sensors • There are sensors to detect • heat • light • collisions • proximity • magnetic fields • pressure

31. Analogue Signals • Most electrical signals are analogue signals. • Analogue signals vary continuously over time. • They can have any value between the upper and lower limits.

32. Digital Signals • Computers can only work with digital signals. • Digital signals have only two values - on or off.

33. Signal Converters • A computer is connected to a device by a circuit called an interface. • The interface must be able to convert the computer’s digital signals to analogue signals if required. • This is done by a digital to analogue converter. • Signals can be changed in the other direction by an analogue to digital converter. • A transducer is a device which changes a physical input e.g. heat, pressure or light into an analogue signal.

34. AD Converter Sensor + (transducer) Analogue to Digital Converter Processor

35. DA Converter Processor Digital to Analogue Converter Device

36. Teaching Robots • Programming by Example (lead-through) • a human guides the robot • the positional sensors in the robot tell the computer about the movement of each joint • the robot’s actuators (motors) repeat the stored sequence of movements.

37. Teaching Robots Programming Robots • a programmer works out the whole sequence of movements and describes them in a high level language • writing a new program will enable the robot to do a different task.

38. Control Languages • Computer programs are always written in a programming language. • You have learned to program in Visual Basic. • Most robots are programmed to move using a special control language. • They use meaningful commands like forward, right, left, wait, grasp, up and down which relate to the robot world.

39. Control Programs Disc/Tape • Stationary robots may have the control program stored on disc or tape. • Can be changed easily.

40. Control Programs ROM Chips • Mobile robots are more likely to have the program stored on a ROM chip. • Chips are more expensive • More permanent • Give a faster start up

41. Social Implications • Disadvantages • workers will lose their jobs. • Some jobs may become de-skilled and offer less job satisfaction

42. Social Implications • Advantages • workers can be retrained to do more interesting and skilled jobs. • fewer people work in dangerous factory conditions. • workers who did boring jobs will have more leisure time. • jobs will increase in the computing and leisure industries.

43. Technical Implications • Safety • moving parts of machine must be covered. • robot vehicles have sensors to detect if anything is in the way • they can be programmed to move slowly so that people can get out of their way • people are kept out of some areas of the factory • robot arms etc. should only operate when an item is in position

44. Economic Implications • Automated Systems are Capital Intensive • very expensive to install • but don’t demand wage rises • don’t require lunch breaks • don’t require canteens and toilet facilities • money will be saved in the long term • Factories used to all be Labour Intensive • large number of workers required • Increased Productivity • more goods manufactured in the same time for the same cost