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