Incorporating motion of upper and lower platforms: A generalized inverse kinematic model for simulation and experimental testing of 6-ups Stewart platform

Abstract

Due to accuracy and precision of parallel manipulators like Stewart platform, several technological applications have relied on them. An accurate kinematic model must be developed in order to improve the manipulator's accuracy. In this paper, inverse kinematic model investigation and verification have been accomplished. Conducting both upper and lower platforms under various motion types is a defining feature of this model. The 3D model of the platform has been directly linked to SimMechanics, paving the way for simulation analysis. MATLAB was used to code the obtained kinematic model. Workspace analysis of the platform has shown the permissible 3D range of each leg, and its intersection consists the total range of the upper platform. Simulation analysis has shown that, position track error hadn't exceeded 10% along any axis, while orientation error hadn't exceeded 2.32% about any axis. In the Experimental model test, the total average error in actuator's displacements is 0.094 cm, while the total average error in rotation angles is 1.145° .

Keywords

• stewart platform
• parallel manipulator
• inverse kinematics
• workspace
• matlab
• simmechanics
• simulation
• experimental model