1. Advisor：Nortren Tsai Speaker：B.Y. Wu
Adaptive Sliding Mode Control System for Nonlinear Single-axis Gyroscope System
Advisor：Nortren Tsai
Speaker：B.Y. Wu
Department of Mechanical Engineering
National Chen Kung University

2. Outline Problem statement System dynamics Adaptive controller design
Adaptive sliding mode controller
Conclusion and future work

3. Background Some issues:
stability
nonlinear phenomena
chaotic dynamics
technical applications
Applications: Gyros for sensing angular motion are used in
airplane automatic pilots
rocket-vehicle launch-guidance
space-vehicle attitude systems
submarine inertial auto-navigation

4. Problem Statement Single-axis gyroscope system.
The closed-loop feedback is designed to account for the gimbal nutation as the gyroscope undergoing an angular velocity in perpendicular direction.
Unknown excitation estimation.

5. Single-axis gyroscopeZ θ Y X
Motor

6. Gyroscope System Model

9. Nonlinear Singular Perturbation Model
Standard form:

11. Reduced Order Model

12. Boundary layer subsystems

13. Adaptive Control

16. Critical Drawbacks The control force is too complex to obtained.
The application is not available and not realizable.
Lack of robustness.
 Adaptive sliding mode control

17. Brief Concept of Sliding Mode Control
Reaching Mode and Sliding Mode
x2=0
Reaching mode
Sliding mode
x1=0
S=0

18. Adaptive Sliding Mode Controller

22. Adaptation Law

23. Analysis of Closed-loop System
Angular velocity excitation varies as
Slowly Time-varying

24. Analysis of Closed-loop System
Regulation capability
SPSMC
ASPSMC

25. Analysis of Closed-loop System
Phase Portrait
START
SPSMC
ASPSMC

26. Analysis of Closed-loop System
Excitation Estimation (Accuracy!)
Estimation
Real

27. Analysis of Closed-loop System
Angular velocity excitation varies as
Fast Time-varying

28. Analysis of Closed-loop System
Regulation capability (A little poor)

29. Analysis of Closed-loop System
Phase Portrait
START

30. Analysis of Closed-loop System
Excitation Estimation
Estimation
Real

31. Conclusion Two control strategies are proposed Adaptive control:
Lack of robustness
Hard to realize
Adaptive sliding mode control:
Better regulation capability than SMC
Good excitation estimation accuracy

32. Future Work SMC for tracking and time-varying problem
Angular velocity excitation estimation:
Fast Time-varying
With large uncertainty
High nonlinearity
Combine fuzzy logic control with adaptive sliding mode control

33. The End
Thanks for Your Listening