The cirle-point analysis method is proposed for the identification on robotic joint-stiffness and backlash.The coupled transmission error of joint-stiffness and backlash modele is built and the calculat ion method of joint error and joint gravity torque is given.An experiment is carried out by taking SRH6C robot as object

which verified the feasibility of this method

then a theory basis to improve the absolute lacation accuracy of the robot is provided.Key words Robot joint Circle-point analysis method Joint stiffness Stiffness parameter identification