A task-space formulation of passive force control

The thesis of the paper is that a passive robotic wrist, of fixed mechanical design, can be programmed to execute a wide range of force control laws of potential use in automated assembly. The authors conduct a systematic study to characterize the range of control laws (given by admittance matrices) implementable by passive programmable mechanical devices. The authors electrical network theory results to identify the admittance matrices which are attainable in the joint-space of the wrist. They then project these matrices in the task-space and compare the range of task-space matrices with a known class of matrices in an attempt to quantify the versatility of passive devices