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A predictive functional control (PFC) scheme for permanent magnet synchronous motor (PMSM) servo systems is proposed in this paper. The PFC-based method is first introduced in the control design of speed loop. Since the accuracy of the PFC model is influenced by external disturbances and speed detection quantization errors of the low distinguishability optical encoder in servo systems, it is noted that the standard PFC method does not achieve satisfactory results in the presence of strong disturbances. This paper adopted the Kalman filter to observe the load torque, the rotor position and the rotor angular velocity under the condition of a limited precision encoder. The observations are then fed back into PFC model to rebuild it when considering the influence of perturbation. Therefore, an improved PFC method, called the PFC+Kalman filter method, is presented, and a high performance PMSM servo system was achieved. The validity of the proposed controller was tested via experiments. Excellent results were obtained with respect to the speed trajectory tracking, stability, and disturbance rejection.

We investigate in-hand regrasping by pushing an object against an external constraint and allowing sliding at the fingertips. Each fingertip is modeled as attached to a multidimensional spring mounted to a position-controlled anchor. Spring compliance maps contact forces to spring compressions, ensuring the fingers remain in contact, and sliding ''compliance'' governs the relationship between sliding motions and tangential contact forces. A spring-sliding compliant regrasp is achieved by controlling the finger anchor motions. We derive the fingertip sliding mechanics for multifingered sliding regrasps and analyze robust regrasping conditions in the presence of finger contact wrench uncertainties. The results are verified in simulation and experiment with a two-fingered sliding regrasp designed to maximize robustness of the operation.

Underwater gliders carried acoustic velocity meters can realize ocean profile observations of the acoustic velocity for long duration and large scale. This paper mainly studies the kinematics and hydrodynamics of the Slocum underwater glider carrying a acoustic velocity meter MINOSX with length 565mm and diameter 76mm. Thus, theory reference for optimal design parameters of the underwater glider is proposed. By establishing the kinematic equations and giving some related parameters, variations with time of the steady-state gliding velocity, pitch angle, gliding path and attack angle are simulated by using Matlab software; The simulation calculations of the hydro-drag and lift are completed by using Fluent software. Finally, this paper summarizes the dynamic characteristics in steady state of the underwater glider in longitudinal plane.