1. Introduction Control Engineering Kim, Do Wan HANBAT NATIONAL UNIVERSITY

2. Outline  Course introduction  What is the control engineering?  Analysis and design objectives  Course objectives

3. Course introduction  Automatic control  For junior student  Text book:  Control Systems Engineering by Norman S. Nise  2 major tests (45%+45%), homeworks (5%), attendance (5%)

4. Course introduction  Covers  Introduction (chap. 1)  Modeling in frequency and time domain (chap. 2-3)  Model reduction (chap. 5)  Time responses (chap. 4)  Steady-state errors (chap. 7)  Stability (chap. 6)  Root locus techniques (chap. 8)

5. Course introduction  Instructor: Kim, Do Wan 2002.2 2004.2 2007.8 2007.10 2008.1 2009.3 2010.3 Yonsei University UC, Berkeley B.S. M.S.Ph.D. Researcher Postdoc Research Professor HANBAT NATIONAL UNIVERSITY

6. Course introduction  Instructor: Do Wan Kim  Research interests: discrete-time, sampled-data, and digital nonlinear control systems, linear and nonlinear systems with nonlinear perturbations, fuzzy systems, and digital redesign.  042-821-1097  N3 215

7. What is the control engineering?  Definition of control systems  A control system is a set of devices (plant, controller) that can provide a desired system response.

8. What is the control engineering?  Definition of control systems  A control system is a set of devices (plant, controller) that can provide a desired system response.  In input-output sense  An example in the morning

9. What is the control engineering?  In elevator  Input? Output?

10. What is the control engineering?  Control systems attempt to either Regulation or Tracking  Regulation – to maintain systems response at CONSTANT desired values system response time desired value constant

11. What is the control engineering?  Regulation – to maintain systems response at CONSTANT desired values system response time desired value constant

12. What is the control engineering?  Tracking – to make system response follow continually CHANGING desired values continually changing system response time desired value

13. What is the control engineering?  Tracking – to make system response follow continually CHANGING desired values continually changing system response time desired value

14. What is the control engineering?  Representation of control system  Differential equation  Kirchhoff’s voltage law and current law, Newton’s laws  Transfer function  State space equation  nth order differential equation= n 1 st order differential equations  Ex)

15. What is the control engineering?  Representation of control system  Block Diagram  Signal flow graph

16. What is the control engineering?  Open-loop vs Closed-loop (Feedback control)  Open-loop systems  No direct comparison between the input and the output.  Sensitive to disturbances  Feedforward control.  Closed-loop (feedback control) systems  Direct comparison between the input and the output.  Less sensitive to disturbances  Feedback Control. Plant Controller Input Output Plant Controller Input Output error + -

17. What is the control engineering?  Open-loop vs Closed-loop (Feedback control)  Open-loop systems  No direct comparison between the input and the output.  Sensitive to disturbances  Feedforward control.  Closed-loop (feedback control) systems  Direct comparison between the input and the output.  Less sensitive to disturbances  Feedback Control. Plant Controller Input Output Plant Controller Input Output error + -

18. What is the control engineering?  Examples

19. What is the control engineering?  Classification

20. What is the control engineering? Control system DistributedLumped  Classification

21. What is the control engineering? Control system DistributedLumped StochasticDeterministic  Classification

22. What is the control engineering? Control system DistributedLumped StochasticDeterministic Discrete-timeContinuous-time  Classification

23. What is the control engineering? Control system DistributedLumped StochasticDeterministic Discrete-timeContinuous-time Nonlinear Linear (L)  Classification

24. What is the control engineering? Control system DistributedLumped StochasticDeterministic Discrete-timeContinuous-time Nonlinear Linear (L) Time-varyingTime-invariant (TI)  Classification

25. Classification  Linear vs Nonlinear  Linear system satisfies the following superposition principle:  Time-invariant vs Time-varying  Check whether its parameter is a function in time or not.

26. Classification  Examples:

27. What is the control engineering?  Examples: robot, missile,….

28. What is the control engineering?  Control engineering is concerned with analysis, design, and implementation of control systems

29.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives

30.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives If it returns to its original position, it is STABLE.

31.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives If it returns to its original position, it is STABLE. If it does NOT returns to its original position, it is UNSTABLE.

32.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives

33.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives Controller

34.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives

35.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives steady-state error:

36.  Stability  Steady-state response (steady-state error)  Transient response (Response speed) Analysis and Design Objectives Slow ResponseFast Response

37. Analysis and Design Objectives  An example: inverted pendulum control system

38. Analysis and Design Objectives  An example: inverted pendulum control system desired system response

39. Analysis and Design Objectives  An example: inverted pendulum control system desired system response

40. Analysis and Design Objectives  An example: inverted pendulum control system desired system response

41. Analysis and Design Objectives  An example: inverted pendulum control system

42. Analysis and Design Objectives  An example: inverted pendulum control system

43. Design procedure  Process

44. Design procedure  Test input

45. Course objectives  Students completing control engineering should:  Understand control theory.  Understand utility of computer tools.

46. Course objectives  Students completing control engineering should:  Understand control theory.  Understand utility of computer tools. Control yourself !