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 E-mail:solanouchi@yahoo.com.tw
Outline Problem statement System dynamics Adaptive controller design Adaptive sliding mode controller Conclusion and future work
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
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.
Single-axis gyroscope Z θ Y X Motor
Gyroscope System Model
Nonlinear Singular Perturbation Model Standard form:
Reduced Order Model
Boundary layer subsystems
Adaptive Control
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
Brief Concept of Sliding Mode Control Reaching Mode and Sliding Mode x2=0 Reaching mode Sliding mode x1=0 S=0
Adaptive Sliding Mode Controller
Adaptation Law
Analysis of Closed-loop System Angular velocity excitation varies as Slowly Time-varying
Analysis of Closed-loop System Regulation capability SPSMC ASPSMC
Analysis of Closed-loop System Phase Portrait START SPSMC ASPSMC
Analysis of Closed-loop System Excitation Estimation (Accuracy!) Estimation Real
Analysis of Closed-loop System Angular velocity excitation varies as Fast Time-varying
Analysis of Closed-loop System Regulation capability (A little poor)
Analysis of Closed-loop System Phase Portrait START
Analysis of Closed-loop System Excitation Estimation Estimation Real
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
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
The End Thanks for Your Listening