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2. Introduction

3. Control The word control is usually taken to mean : - regulate, ????? ???? - direct, ????? ???? - command ?????? ????? . 3

4. Control system A control system is an arrangement of physical components connected or related in such a manner as to command, direct, or regulate itself or another system. 4

5. 5 Figure: 01-01 represents a block diagram of a process or component to be controlled. The input - output relationship represents the cause-effect relationship of the process, which represents a processing of the input signal to provide an output signal variable, often with power amplification.Figure: 01-01 represents a block diagram of a process or component to be controlled. The input - output relationship represents the cause-effect relationship of the process, which represents a processing of the input signal to provide an output signal variable, often with power amplification.

6. Input The input is the excitation or command applied to a control system. Typically from external energy source, usually in order to produce a specified response from the control system. 6

7. Output The output is the actual response obtained from a control system. It may or may not be equal to specified response implied by the input. 7

8. In Summary Input - Excitation applied to a control system from an external source. Output - The response obtained from a system Feedback - The output of a system that is returned to modify the input. Error - The difference between the reference input and the output. 8 Discuss SlideDiscuss Slide

9. Disturbance in a feedback control system Disturbance signal is an unwanted extraneous input signal that affects the system�s output signal. Feedback control can completely or partially eliminate the effect of disturbance signal. 9

10. Negative Feedback Control System 10 1. All weapons system must have some form of control system. Normally a negative feedback control system. 2. Input: Stimulus or excitation to a control system from an external source usually in order to produce a specific response from the system. Example: signal sent from a radar dish to the weapons control computer. 3. Output: The response from the system such as a gun turning toward target. 4. Feedback: That portion the output of a system that is returned to modify the input and thus serve as a performance monitor. Example: The gun needs to tell the weapons computer where it is pointing so that the computer can compare that to where it should be pointing. 5. Error: The difference between the input stimulus and the output response. Specifically the difference between the input and feedback. Discuss the + and - signs on the Comparater and the error is reference signal minus the feedback signal.1. All weapons system must have some form of control system. Normally a negative feedback control system. 2. Input: Stimulus or excitation to a control system from an external source usually in order to produce a specific response from the system. Example: signal sent from a radar dish to the weapons control computer. 3. Output: The response from the system such as a gun turning toward target. 4. Feedback: That portion the output of a system that is returned to modify the input and thus serve as a performance monitor. Example: The gun needs to tell the weapons computer where it is pointing so that the computer can compare that to where it should be pointing. 5. Error: The difference between the input stimulus and the output response. Specifically the difference between the input and feedback. Discuss the + and - signs on the Comparater and the error is reference signal minus the feedback signal.

11. Terms and Concepts 11

12. Control system A control system is an interconnection of components forming a system configuration that will provide a desired system response. 12

13. Two Types of Control Systems Open Loop No feedback Difficult to control output with accuracy Closed Loop Must have feedback Must have sensor on output Almost always negative feedback 13

14. Open-loop control An open-loop control system utilizes an actuating device to control the process directly without using feedback. Must be closely monitored. A common example of an open-loop control system is an electric toaster in the kitchen. 14 A microwave oven set to operate for a fixed time.A microwave oven set to operate for a fixed time.

15. 15 Figure: 01-21 Figure: 01-21

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18. Closed-loop control A closed-loop control system uses a measurement of the output and feedback of this signal to compare it with the desired output. Continually adjusts the process. 18

19. 19 The system in Figure: 01-22 is a negative feedback control system, because the output is subtracted from the input and the difference is used as a the input signal to the controller. The system in Figure: 01-22 is a negative feedback control system, because the output is subtracted from the input and the difference is used as a the input signal to the controller.

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22. 22 Figure: 01-07a-c, An example of a closed-loop control system is a person steering an automobile (assuming his eyes are open) by looking at the auto�s location on the road and making the appropriate adjustments.Figure: 01-07a-c, An example of a closed-loop control system is a person steering an automobile (assuming his eyes are open) by looking at the auto�s location on the road and making the appropriate adjustments.

23. 23 Figure: 01-08. Manual control system for regulating the level of fluid in a tank by adjusting the output valve. The operator views the level of fluid through a port in the side of the tank. The input is a reference level of fluid that the operator is instructed to maintain (this reference is memorized by the operator). The power amplifier is the operator, and the sensor is visual. The operator compares the actual level with the desired level and opens or closes the valve ( actuator), adjusting the fluid flow out, to maintain the desired level.Figure: 01-08. Manual control system for regulating the level of fluid in a tank by adjusting the output valve. The operator views the level of fluid through a port in the side of the tank. The input is a reference level of fluid that the operator is instructed to maintain (this reference is memorized by the operator). The power amplifier is the operator, and the sensor is visual. The operator compares the actual level with the desired level and opens or closes the valve ( actuator), adjusting the fluid flow out, to maintain the desired level.

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25. The roles of feedback Reduce error (eliminating the error) Reduce sensitivity or Enhance robustness Disturbance rejection or elimination Improve dynamic performance or adjust the transient response (such as reduce time constant) 25

26. Major Types of Feedback Used Position Feedback Used when the output is a linear distance or angular measurement. Rate & Acceleration Feedback Feeds back rate of motion or rate of change of motion (acceleration) Motion smoothing Uses a electrical/mechanical device call an accelerometer 26 1. Discuss slide. 2. A you can see from the example of the gun turret, these types of feedback provide additional information that is used to improve the response time of the system. - The light on when the proper position was reached. But... - The additional information modifies the system response and improve the response time. 3. This additional information when add to the feedback loop is call DAMPING.1. Discuss slide. 2. A you can see from the example of the gun turret, these types of feedback provide additional information that is used to improve the response time of the system. - The light on when the proper position was reached. But... - The additional information modifies the system response and improve the response time. 3. This additional information when add to the feedback loop is call DAMPING.

27. Control systems are divided into two classes: a) If the aim is to maintain a physical variable at some fixed value when there are disturbances, this is a regulator. Example: speed-control system b) The second class is the servomechanism. This is a control system in which a physical variable is required to follow (track) some desired time function. Example: an automatic aircraft landing system, or a robot arm designed to follow a required path in space.

28. 28 Figure: 01-04Figure: 01-04

29. 29 Figure: 01-11 Coordinated control system for a boiler-generator. This is an example of the importance of measuring many variables, such as oxygen, temperature, pressure, and generation, to provide information to the computer for control calculations. Another important industry, the metallurgical industry, has had considerable success in automatically controlling its processes. A hot-strip steel mill is controlled for temperature, strip width, thickness, and quality.Figure: 01-11 Coordinated control system for a boiler-generator. This is an example of the importance of measuring many variables, such as oxygen, temperature, pressure, and generation, to provide information to the computer for control calculations. Another important industry, the metallurgical industry, has had considerable success in automatically controlling its processes. A hot-strip steel mill is controlled for temperature, strip width, thickness, and quality.

30. 30 Figure: 01-09Figure: 01-09

31. Automation - The control of a process by automatic means. Closed-loop feedback control system - A system that uses a measurement of the output and compares it with the desired output. 31

32. Design-The process of conceiving or inventing the forms, parts, and details of a system to achieve a specified purpose. Feedback signal - A measure of the output of the system used for feedback to control the system. Multivariable control system - A system with more than one input variable or more than one output variable. 32

33. Negative feedback -The output signal is fed back so that it subtracts from the input signal. Negative feedback initiates to maintain or regulate physiological functions within a set and narrow range. Open-loop control system - A system that utilizes a device to control the process without using feedback. Optimization -The adjustment of the parameters to achieve the most favorable or advantageous design. 33 Open-loop control system - The output has no effect upon the signal to the process.Open-loop control system - The output has no effect upon the signal to the process.

34. Positive feedback -The output signal is fed back so that it adds to the input signal. Positive feedback mechanisms are designed to accelerate or enhance the output created by a stimulus that has already been activated. In positive feedback systems the presence of a product (or signal) results in an increase in the production (amplification) of that product (or signal). Process -The device, plant, or system under control. Productivity -The ratio of physical output to physical input of an industrial process. 34 stimulus: ????? stimulus: ?????

35. Synthesis - The combining of separate elements or devices to form a coherent whole. System - An interconnection of elements and devices for a desired purpose. 35 ?????? :coherent?????? :coherent

36. The Control System Design Process

37.  Design is the process of conceiving or inventing the forms, parts, and details of a system to achieve a specified purpose. 37

38. Engineering design Trade-off The result of making a judgment about how to compromise between conflicting criteria. 38

39. Control system engineers are concerned with understanding and controlling segments of their environment, often called systems, to provide useful economic products. 39

40. Goals Twin goals of understanding and controlling are complementary because effective systems control requires that the systems be understood and modeled. 40

41. Control engineering Control engineering is based on the foundations of feedback theory and linear system analysis, and it integrates the concepts of network theory and communication theory. 41

42. Given a process, how to design a feedback control system? Three steps: Modeling. Obtain mathematical description of the systems. Analysis. Analyze the properties of the system. Design. Given a plant, design a controller based on performance specifications. The course spans each of these steps in that sequence. 42

43. The basis for analysis of a system is the foundation provided by linear system theory, which assumes a cause-effect relationship for the components of a system. 43

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46. 46 The design of control systems is a specific example of engineering design. The goal of control engineering design is to obtain the configuration, specifications, and identification of the key parameters of a proposed system to meet an actual need. The design process consists of seven main building blocks, which are arrange into three groups: Establishment of goals and variables to be controlled, and definition of specifications against which to measure performance System definition and modeling Control system design and integrated system simulation and analysis The design of control systems is a specific example of engineering design. The goal of control engineering design is to obtain the configuration, specifications, and identification of the key parameters of a proposed system to meet an actual need. The design process consists of seven main building blocks, which are arrange into three groups: Establishment of goals and variables to be controlled, and definition of specifications against which to measure performance System definition and modeling Control system design and integrated system simulation and analysis

47. Design 1 47

48. Design 2 48

49. Design 3 49

50. 50 The design of control systems is a specific example of engineering design. The goal of control engineering design is to obtain the configuration, specifications, and identification of the key parameters of a proposed system to meet an actual need. The design process consists of seven main building blocks, which are arrange into three groups: Establishment of goals and variables to be controlled, and definition of specifications against which to measure performance System definition and modeling Control system design and integrated system simulation and analysis The design of control systems is a specific example of engineering design. The goal of control engineering design is to obtain the configuration, specifications, and identification of the key parameters of a proposed system to meet an actual need. The design process consists of seven main building blocks, which are arrange into three groups: Establishment of goals and variables to be controlled, and definition of specifications against which to measure performance System definition and modeling Control system design and integrated system simulation and analysis

51. Design examples

52. Rotating disk speed control 52 Many modern devices employ a rotating disk held at a constant speed. A CD player requires a constant speed of rotation in spite of motor wear and variation and other components changes. Many modern devices employ a rotating disk held at a constant speed. A CD player requires a constant speed of rotation in spite of motor wear and variation and other components changes.

53. Step 1. Control goal Design a system that will held a rotating disk at a constant speed. Ensure that the actual speed of rotation is within a specified percentage of desired speed. 53 To obtain disk rotation, we will select a DC motor as the actuator because it provides a speed proportional to the applied motor voltage. For the input voltage to the motor, we will select an amplifier that can provide the required power.To obtain disk rotation, we will select a DC motor as the actuator because it provides a speed proportional to the applied motor voltage. For the input voltage to the motor, we will select an amplifier that can provide the required power.

54. Step 2. Variable to be controlled Speed of rotation disc 54 In next chapters, we will have the tools to quantitatively describe the control design specifications using a variety of steady-state performance specifications and transit response specifications, both in the time-domain and in the frequency domain.In next chapters, we will have the tools to quantitatively describe the control design specifications using a variety of steady-state performance specifications and transit response specifications, both in the time-domain and in the frequency domain.

55. Step 3. Control design specification Design a system that will ensure that the actual speed of rotation is within a specified percentage of desired speed. 55 Given the design goals, variables to be controlled, and control design specification we can now propose a preliminary system configuration. An open-loop system would use a battery source to provide a voltage that is proportional to the desired speed as shown in Fig. 1.21a. This voltage is amplified and applied to the motor. Given the design goals, variables to be controlled, and control design specification we can now propose a preliminary system configuration. An open-loop system would use a battery source to provide a voltage that is proportional to the desired speed as shown in Fig. 1.21a. This voltage is amplified and applied to the motor.

56. 56 Figure: 01-21Figure: 01-21

57. 57 The system in Figure: 01-22 is a negative feedback control system, because the output is subtracted from the input and the difference is used as a the input signal to the controller. The feedback control system would use a tachometer as a sensor that provides an output voltage proportional to the speed of its shaft. The error voltage is generated by the difference between the input voltage and the tachometer voltage.as shown in Fig. 1.22a. We expect the feedback system to be superior to the open-loop system because the feedback system will respond to errors and act to reduce them. With precision components, we could expect to reduce the error of the feedback system to one-hundredth of error of the open-loop system The system in Figure: 01-22 is a negative feedback control system, because the output is subtracted from the input and the difference is used as a the input signal to the controller. The feedback control system would use a tachometer as a sensor that provides an output voltage proportional to the speed of its shaft. The error voltage is generated by the difference between the input voltage and the tachometer voltage.as shown in Fig. 1.22a. We expect the feedback system to be superior to the open-loop system because the feedback system will respond to errors and act to reduce them. With precision components, we could expect to reduce the error of the feedback system to one-hundredth of error of the open-loop system

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59. Insulin delivery system Automatic system can be used to regulate blood pressure, blood sugar level, and heart rate. Automatic system can be used to regulate blood pressure, blood sugar level, and heart rate.

60. 60 Figure: 01-23. The blood glucose and insulin concentrations for a healthy person.Figure: 01-23. The blood glucose and insulin concentrations for a healthy person.

61. Step 1. Control goal Design a system to regulate the blood sugar concentration of a diabetic by controlled dispensing of insulin. 61

62. Step 2. Variable to be controlled Blood glucose concentration 62 In next chapters, we will have the tools to quantitatively describe the control design specifications using a variety of steady-state performance specifications and transit response specifications, both in the time-domain and in the frequency domain.In next chapters, we will have the tools to quantitatively describe the control design specifications using a variety of steady-state performance specifications and transit response specifications, both in the time-domain and in the frequency domain.

63. Step 3. Control design specification Provide a blood glucose level for the diabetic that closely approximates the glucose level of a healthy person. 63 Given the design goals, variables to be controlled, and control design specification we can now propose a preliminary system configuration. An open-loop system would use a preprogrammed signal generator and miniature motor pomp to regulate the insulin delivery rate as shown in Fig. 1.24 a. The feedback control system would use a sensor to measure the actual glucose level and compare that level with the desired level, thus turning the motor pump on when it is required as shown in Fig. 1.24 bGiven the design goals, variables to be controlled, and control design specification we can now propose a preliminary system configuration. An open-loop system would use a preprogrammed signal generator and miniature motor pomp to regulate the insulin delivery rate as shown in Fig. 1.24 a. The feedback control system would use a sensor to measure the actual glucose level and compare that level with the desired level, thus turning the motor pump on when it is required as shown in Fig. 1.24 b

64. 64 Figure: 01-24 Open-loop system for drug delivery, in which mathematical models of the dose-effect relationship of the drugs are used. The best solutions rely on individually, pocket-sized insulin pumps that can deliver insulin according to a preset time history. More complicate systems will use closed-loop control for the measured blood glucose level. Figure: 01-24 Open-loop system for drug delivery, in which mathematical models of the dose-effect relationship of the drugs are used. The best solutions rely on individually, pocket-sized insulin pumps that can deliver insulin according to a preset time history. More complicate systems will use closed-loop control for the measured blood glucose level.

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67. Controlling the position of a missile launcher from a remote location The input is the desired angular position of the missile launcher, The control system consists: of potentiometer, power amplifier, motor, gearing between the motor and the missile launcher, missile launcher. 67

68. A position open loop control 68

69. A position closed loop control 69 The previous example is modified by introducing a position feedback loop.The previous example is modified by introducing a position feedback loop.

70. Applications Automatic system can be used to regulate blood pressure, blood sugar level, and heart rate. Automatic system can be used to regulate blood pressure, blood sugar level, and heart rate.

71. Applications Control engineering is not limited to any engineering discipline but is equally applicable to: aeronautical, chemical, mechanical, computer science and engineering , civil engineering, electrical engineering. 71

72. Prerequisite by topics Knowledge and proficiency in Matlab Concept and solution of linear ordinary differential equations Laplace transform and its applications Poles, zeros, transfer functions, frequency response, Bode plots Vectors and matrices Complex numbers 72