Deflection prediction for serial manipulators

Abstract

A method of deflection analysis for a general serial manipulator which considers end-effector, gravity, and inertial loads is described. The conceptualized manipulator can have many degrees of freedom and be of the most general geometry. The analysis returns end-effector error based on a quasi-static approach. Thus, small oscillations (due to vibrations) are ignored and the inertial loads are considered applied loads. A kinematic analysis based on geometric influence coefficients is used to obtaining resultant joint loads. A flexibility analysis sufficient to describe general link deformation is performed to yield the local link deformations. These local values are transformed to end-effector deflections through the use of the kinematic influence coefficients as a first order approximation. End-effector deflection due to flexibilities in the joint actuators is addressed. A description of the generalized end-effector spring is presented.