A design method on joint torque feedback control system

The authors presented a systematic analysis and design of a position control system with a PD controller plus joint torque feedback in a previous article (see IEEE Control Systems, vol. 18, no. 1, p. 48-55, 1998). It was found that there exists a trade-off relationship between the vibration suppression and the disturbance rejection. In this paper, an additional integral control approach is introduced to the above-mentioned system for improving the disturbance rejection characteristic. By means of pole assignment design, feedback control coefficients and a contraint relation are explicitly derived. Furthermore, by simplifying the constraint relation, the authors present a pole assignment design method with identical real parts. The domain of the pole assignment is discussed. Finally, the validity of the proposed design has been verified by simulations and experiments