Abstract:Aiming at the precision of parallel robot, this performance index, the influence of the rod length error of the 3RRR parallel robot on the whole mechanism was analyzed.By using the Jacobi matrix method, the relationship between the 3RRR parallel robot and the rod length error of singular positionwas analyzed theoretically.The corresponding error model was established according to the result of the solution, andthe singular position under ideal condition was calculated and the singular position error of rod length under the condition of the degree of deviation was considered in MATLAB, and then the calculated deviation data were analyzed and shown in the form of an image.Finally, the relationship of deviation degreeis concluded between the rod length error and the singular position of the 3RRR mechanism at different rod,providing a scientific reference for the design accuracy in need of the mechanism.