Affiliations: [a] School of Mechatronics Engineering, University of
Electronic Science and Technology of China, Chengdu, China | [b] School of Mechanical Engineering, Xi'an Jiaotong
University, Xi'an, China | [c] Department of Electrical Engineering, Eindhoven
University of Technology, Eindhoven, The Netherlands
Abstract: This paper addresses the anti-vibration control produced by
manipulator movements of contactless planar actuator with manipulator (CPAM).
The manipulator on top of the planar actuator has 2-DOF which provides precise
linear and rotary movement of the end tip of the manipulator. The successful
suppression of the vibration will improve the position accuracy of the CPAM.
For the purpose of the anti-vibration control design, a platform of 3-DOF
contactless planar actuator with 2-DOF manipulator has been designed and
manufactured. The platform, that mimics the magnetic array of the planar
actuator, is suspended by 9 voice coils which are distributed into regular
array to simulate the topology of the planar actuator and will be used for
gravity compensation and for manipulator platform control in 3-DOF: vertically
and two tilting angles. The other 3-DOF is fixed by the suspension system
consisting of 3 stiff rods. Nine inductive sensors are mounted on the base
plate to measure the posture of the platform when the manipulator is working.
The CPAM model is based on rigid body dynamics and movement of the manipulator
is taken as a disturbance in the platform control. According to the concept of
loop shaping, robust H∞ controllers for each of the DOF
of the platform are then designed depending on the estimated disturbance force
and torque from the manipulator. Control responses in 3-DOF are then presented.
The results illustrate high positioning stability.
Keywords: Contactless planar actuator, anti-vibration control, magnetic levitation, loop shaping
