Compliant design for intrinsic safety: general issues and preliminary design

We describe some initial results of a project aiming at the development of a programmable compliance, inherently safe robot arm for applications in anthropic environments. In order to obtain safety in spite of worst-case situations (such as unexpected delays in teleoperation, or even controller failure), we propose an approach to achieving the compliance by mechanical rather than by control design. We first describe some of the control problems encountered in a typical, large, possibly unknown mechanical compliance, and present the result that shows the possibility to cope with these uncertainties in an adaptive way. Next, we describe the initial development of a new prototype arm under construction in our laboratory. The arm is designed to achieve arbitrary position tracking in 3D with controlled effective compliance at the joints.