Aerospace Knowledge and Technology Journal

Aerospace Knowledge and Technology Journal

Design, analysis and implementation of a 6-degree-of-freedom Stuart platform using an inverse kinematics control system and a PID controller to simulate complex motions in industrial applications and flight simulators

Document Type : Research Paper

Author
M. Abolfazl Mokhtari
Associate Professor Faculty of Engineering and Flight, Imam Ali University, Tehran, Iran.
Abstract
In this study, a Stuart platform with 6 degrees of freedom has been designed and implemented, which has better performance than serial robots due to its parallel structure. In order to stabilize the platform position, an inverse kinematics control system with PID controllers was designed and implemented for each leg. For a given position, the length of the arms is calculated through inverse kinematics and with the help of stepper motors, each leg reaches the desired length. Practical experiments showed that the PID controller is able to maintain the desired position in the presence of common disturbances such as electrical noise or sudden load changes with a maximum error of ±0.5 mm and mechanical vibrations. In addition, the platform motion system using stepper motors has a stable performance with a positioning accuracy of ±0.1 mm and a response time of 0.2 seconds under nominal load conditions and is able to effectively implement complex movements in simulations and industrial applications. The system accuracy was confirmed with a standard deviation of 0.05 mm in 100 replicate tests, and the accuracy and efficiency of the proposed controller have been verified.
Keywords
Stewart platform
6 degrees of freedom
kinematics
controller
Subjects
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Aerospace Knowledge and Technology Journal
Volume 14, Issue 1
May 2025
Pages 217-231