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This article proposes a new reconfigurable parallel mechanism using a spatial overconstrained platform. This proposed mechanism can be used as a machine tool. The mobility is analyzed by Screw Theory. The inverse kinematic model is established by applying the closed-loop equation. Next, the dynamic model of the presented mechanism is established by Lagrange formulation. To control the presented mechanism, some controllers have been used. Based on this dynamic model, the fuzzy-proportion integration differentiation (PID) controller is designed to track the trajectory of the end effector. For each limb, a sliding mode controller is applied to track the position and velocity of the slider. Finally, some simulations using ADAMS and MATLAB are proposed to verify the effectiveness and stability of these controllers.

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This paper aims to develop an active disturbance rejection controller design scheme for compass-like biped robots. In the previous study, with a special designed mechanical structure on compass-like biped, we have generated a high-efficient walking gait. The original controller applied linearization approximation based on the method transverse coordinate control, with which the ability of disturbance rejection is insufficient. We introduce the active disturbance rejection controller method into the control scheme, which only requires the information of angular momentum and has the ability to compensate the model error and the external disturbance. With the new control strategy, the linearization approximation method is replaced by an active disturbance rejection controller and the robustness is improved. In order to further apply this control method, a switching control strategy has been proposed and a series of numerical simulations show that active disturbance rejection controller has a good disturbance rejection effect.