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The purpose of this paper is to discuss the design and fabrication of magnetic couplings to use for vacuum robots. The permanent magnetic coupling (PMC) is appropriate for torque transmission in ultrahigh vacuum and highly clean environments. However, conventional structures of PMC are always unsuitable to use for vacuum robots.

Two types of design scheme for radial magnetic couplings are introduced and compared. The major characteristic of the novel design scheme is that the inner part uses a nonmagnetic mantle to enclose the magnets and yoke, and the outer part uses two end closures to position magnets. The locating groove on the end closure may be manufactured as T‐shape or dovetail shape.

The 3D finite element analysis simulation results and experimental studies have demonstrated that the proposed Design B had a lower contamination rate and a higher transmission efficiency than the Design A.

The limitation of the research to date is that issues of control, path‐planning, and communication have not yet been addressed.

The proposed PMC is successfully applied in vacuum robots which uses combined direct drive techniques and magnetic transmit techniques.

These results suggest that the proposed PMC is suitable for using in vacuum robots.

Based on the inverse kinematics and task space dynamic model, this paper aims to design a high-precision trajectory tracking controller for a 2-DoF translational parallel manipulator (TPM) driven by linear motors.

The task space dynamic model of a 2-DoF TPM is derived using Lagrangian equation of the first type. A task space dynamic model-based feedforward controller (MFC) is designed, which is combined with a cascade PID/PI controller and velocity feedforward controller (VFC) to construct a hybrid PID/PI+VFC/MFC controller. The hybrid controller is implemented in MATLAB/dSPACE real-time control platform. Experiment results are given to validate the effectiveness and industrial applicability of the hybrid controller.

The MFC can compensate for the nonlinear dynamic characteristics of a 2-DoF TPM and achieve better tracking performance than the conventional acceleration feedforward controller (AFC).

The task space dynamic model-based hybrid PID/PI+VFC/MFC controller is proposed for a 2-DoF linear-motor-driven TPM, which reduces the tracking error by at least 15 percent compared with conventional hybrid PID/PI+VFC/AFC controller. This control scheme can be extended to high-speed and high-precision trajectory tracking control of other parallel manipulators by reprogramming the feedforward signals of traditional cascade PID/PI controller.