Developing a real-time serial servo motion control system for electric stewart platform

Stewart platform, a parallel mechanism platform with six degree-of-freedoms, has high load force and precision positioning. It´s often applied in motion simulators to perform dynamic linear and rotating (angular) motions. The early Stewart platforms used hydraulic system as the driving mechanism. As the electronic control, electric servo drive system and serial servo control technologies emerge in industrial applications, the advantages of low-cost and high-efficiency help the electric servo drive system gradually replace the traditional hydraulic drive system in many industrial systems, including the Stewart platforms. However, the non-real-time performance of existing serial servo control for multiple motors was uncovered, which is improper for real-time interactive control of the Stewart platform. To solve the problem, this research develops a real-time serial servo motion control system for electric Stewart platform. In this study, an electric Stewart platform control system is tested with a real-time control program which is written based on the multi-thread concept and with a high-precision timer. The algorithm developed in this study improves the real-time performance of electric Stewart platform control system, and successfully corrects the defect of improper real-time command update in the serial servo control system.