Force, compliance and position control for a space frame manipulator

This paper describes practical methods for achieving variable force, compliance and position control for a direct-drive, pneumatically powered "variable geometry truss manipulator" (VGTM) built at University of Southern Queensland. The advantages of tetrahedral-tetrahedral VGTM structures are discussed including the kinematics for a fully operational prototype. The natural compliant behaviour of compressed gas is exploited using proportional valve control software. Experimental results are included for force and position control of a conventional pneumatic actuator.