Abstract:
On a new demand of safe human-robot interaction for robotic applications, the Compact Compliant Actuator, named CompActTM, is recently developed with physical compliance ...Show MoreMetadata
Abstract:
On a new demand of safe human-robot interaction for robotic applications, the Compact Compliant Actuator, named CompActTM, is recently developed with physical compliance and active variable damping. In this mechanism, a desired physical damping behavior is realized by generating a friction force which is actively controlled by piezoelectric actuators (PEAs). However, nonlinearities such as hysteresis and creep effect make difficult to precisely control the generated piezoelectric force. This paper focuses on a development of precise force tracking controller for PEAs. A time delay estimation (TDE) using a force feedback is newly proposed to compensate a hysteretic behavior of the PEA and external uncertainties without a mathematical model. Thanks to the force-based TDE, the proposed control is accurate, computationally efficient and easily implementable on the real PEA system. The proposed control scheme is experimentally verified on the CompActTM. Root-mean-square values of the steady-state error for step commands are kept as less than error ratio of 0.13 % and the closed-loop system bandwidth for sinusoidal commands of 20 N stroke is confirmed as about 11 Hz under 100 N payload. In addition, the stability of the proposed control is proved to be bounded-input-bounded-output (BIBO) stable.
Date of Conference: 31 May 2014 - 07 June 2014
Date Added to IEEE Xplore: 29 September 2014
Electronic ISBN:978-1-4799-3685-4
Print ISSN: 1050-4729