A Novel 4DoF Robotic Link Mechanism with ECoSMo: Kinematics Based Torque Analysis In this study, a novel four degrees of freedom (DoF) robotic link mechanism and its torque analysis based on extended coaxial spherical joint module (ECoSMo) are introduced. The ECoSMo is a previously developed 4DoF pointcentered rotational parallel mechanism with coaxial actuators. The use of the ECoSMo on robotic system is expected to improve dynamic performance since all actuators are mounted on fixed base. Furthermore, output torque is amplified in a specific axial direction, due to a coaxial parallel mechanism. Torque analysis of the mechanism is derived based on kinematics of a virtual 4DoF serial linkages and the ECoSMo. A virtual forcebased position control simulation is performed for verifying the torque analysis. Due to the valid torque analysis, the norm of position error is less than 0. 7mm. It is confirmed that the output torque is amplified compare to actuator torques, which is a special feature of the ECoSMo. Control experiments using prototype are also carried out to validate the feasibility.

Decoupling Control and Simulation of a 3RSR Spheroid Parallel Wrist The control of position and trajectory tracking are critical issues in parallel robots. Traditional PID tracking algorithms, which are based on kinematics control use the position and speed deviation as a negative feedback in order to design a controller. However, this method is not only hard to maintain the excellent dynamic and static quality of a system, but it is also incapable of realizing complete decoupling, and it needs large energy to be controlled. To overcome such drawbacks, this paper proposes, a computed torque decoupling control strategy for a 3RSR spheroid parallel mechanism. The control strategy includes a computed torque decoupling control method with traditional PD controller and selfadaption fuzzy controller. It was proved that the corresponding Lyapunov function is global asymptotic stable in the ideal and nonideal estimation. A set of ADAMSMATLAB dynamic simulations were established based on virtual prototyping technology. The results demonstrated that the performance of the control scheme with selfadaption fuzzy controller is more effective than that with PD controller.