Dexterous workspace optimization of an asymmetric six-degree of freedom Stewart–Gough platform type manipulator

•Actuator types 8 produce superior dexterous workspace characteristics.•Actuator 8 is unique type that produce dexterous workspace beyond LCI>0.5.•Radiuses of base platforms are commonly optimized bigger than the moving platform.•Best platform orientation angles for D15D3 &TSPM vary between −2° and 6°.•Moving platform radius can be used as a weighting factor to homogenize Jacobian.

In this paper, an asymmetric Generalized Stewart–Gough Platform (GSP) type parallel manipulator is designed by considering the type synthesis approach. The asymmetric six-Degree Of Freedom (DOF) manipulator optimized in this paper is selected among the GSPs classified under the name of 6D. The dexterous workspace optimization of Asymmetric parallel Manipulator with tEn Different Linear Actuator Lengths (AMEDLAL) subject to kinematics and geometric constraints is performed by using the Particle Swarm Optimization (PSO). The condition number and Minimum Singular Value (MSV) of homogenized Jacobian matrix are employed to obtain the dexterous workspace of AMEDLAL. Finally, the six-DOF AMEDLAL is also compared with the optimized Traditional Stewart–Gough Platform Manipulator (TSPM) considering the volume of the dexterous workspace in order to demonstrate its kinematic performance. Comparisons show that the manipulator proposed in this study illustrates better kinematic performance than TSPM.