To solve the problem of disturbance to the tracking motion of the manipulator due to grasping different masses and telescopic links,a manipulator disturbance observation method combining constant and time-varying gain was proposed,and the stability of the observation error system was analyzed,so as to obtain the disturbance in the working process of the manipulator and design a controller to compensate the disturbance.Meanwhile,to improve the safety of the robot manipulator motion,a nonlinear robust control method combined with model predictive controlτp(t) was proposed,by which the safe motion state of the system was obtained by simultaneously constraining the position tracking error and the velocity tracking error of the manipulator motion,then the manipulator was ensured to realize the safe and stable tracking motion.Through the comparative analysis of simulation results,the effectiveness of the proposed disturbance observation method and the superiority of restraining disturbance to realize the safety of motion state are proved.