Optimal Force Compensating Control of Robotic Lifting Mechanisms

In this paper a method for development of precise control of robotic lifting mechanisms using force compensating systems (FCS) is considered. In this case the optimal control of electromechanical systems is offered to use. The authors propose system modeling with the application of linearized mathematical description. The goal of the research is solving of the synthesis problem for the FCS controller with elastic mechanical links and transmissions, friction and inertia forces as well as external force disturbances of the mechanisms of a robotic devices and a moving object. The considered electromechanical system of robotic mechanism is researched in the form of the Mason's directed line graph. The application of the integral method allowed determining the efficient structure of the control system, to synthesize the optimal parameters of the force controller with indefinite external disturbances. Completed theoretical and experimental studies of the using of an optimal force controller is showed the effectiveness of the developing FCS for robotic lifting mechanisms. The optimal force controller allows reducing the control static error up to 36.5 times and the force overshoot in the elastic transmission by 14 times as compared with the driveless original mechanical system. The offered synthesis method of an optimal force controller was field-tested when creating balanced manipulators of the type MP100.