Nonlinear Vibration Control Experimental System Design of a Flexible Arm Using Interactive Actuations from Shape...

Area of Science:

• Robotics and Control Systems
• Materials Science
• Mechanical Engineering

Background:

• Flexible arms are prone to vibrations due to thin structures, impacting operational accuracy.
• Vibration suppression is crucial for enhancing the performance of flexible arm systems.
• Smart materials, particularly shape memory alloys (SMAs), offer potential for vibration control due to their unique properties.

Purpose of the Study:

• To design and experimentally validate a nonlinear vibration control system for a flexible arm using interactive actuation from shape memory alloy (SMA).
• To investigate the effectiveness of an integrated control strategy combining an operator-based controller, an integral compensator, and an n-times feedback loop.
• To compare the proposed control method's performance against a conventional proportional-derivative (PD) controller.

Main Methods:

• Development of an experimental system featuring an interactive actuator-sensor-controller combination with SMA.
• Implementation of a vibration suppression strategy integrating an operator-based nonlinear vibration controller, an integral compensator with an estimation mechanism, and an n-times feedback loop.
• Experimental validation through three distinct cases to assess vibration reduction and tracking performance.

Main Results:

• The integrated control system significantly reduced vibration displacement compared to using the controller alone.
• Increasing the n-times feedback loop enhanced tracking performance, approaching optimal control as n tended to infinity.
• The proposed method stabilized vibration displacement within 4 waveforms, outperforming the conventional PD controller (7 waveforms).
• The experimental results demonstrated faster vibration reduction and lower input power requirements compared to traditional methods.

Conclusions:

• The proposed interactive actuation vibration control approach using SMA is effective and superior to conventional methods.
• The integrated control strategy offers robust stability and optimal vibration reduction for flexible arms.
• This research provides a practical and efficient solution for suppressing vibrations in flexible arm systems.