Computation and analysis of compliance in grasping and fixturing

Abstract

This paper presents a method to compute stiffness matrices for compliant grasps and fixtures. While the linear spring contact model has been widely used by robotics researchers, it is in general not accurate for practical applications. More realistic models, including the well-verified Hertz model, are incorporated by use of overlap functions. We derive a stiffness matrix formula that considers surface and material properties of the contacting bodies and applies to both planar and solid grasps. The effects of contact geometry are analyzed and illustrated with examples.