This paper presents a method to generate feasible, unique forward-kinematic solutions for a general Stewart platform. This is done by using inverse kinematics to obtain valid workspace data and corresponding actuator lengths for the moving platform. For parallel kinematic machines, such as the Stewart Platform, inverse kinematics are straight forward, but the forward kinematics are complex and generates multiple solutions due to the closed loop structure of the kinematic links. In this research, a simple iterative algorithm has been used employing modified Denavit-Hartenberg convention. The outcome is encouraging as this method generates a single feasible forward kinematic solution for each valid pose with the solved DH parameters and unlike earlier forward kinematics solutions, this unique solution does not need to be manually verified. Therefore, the forward kinematic solutions can be used directly for further calculations without the need for manual pose verification. This capability is essential for the six degree of freedom materials testing system developed by the authors in their laboratory. The developed system is aimed at characterizing additively manufactured materials under complex combined multiple loading conditions. The material characterization is done by enabling high precision force control on the moving platform via in situ calibration of the as-built kinematics of the Stewart Gough Platform.

翻译：本文提出一种为通用Stewart平台生成可行且唯一正运动学解的方法。该方法通过逆运动学获取移动平台的有效工作空间数据及对应的作动器长度。对于Stewart平台这类并联运动机构，其逆运动学求解较为直接，但由于运动链的闭环结构，正运动学问题复杂且存在多解性。本研究采用改进的Denavit-Hartenberg约定，构建了简单的迭代算法。结果表明：该方法能为每个有效位姿生成单一可行正运动学解，并通过已求解的DH参数实现；与早期正运动学解法不同，该唯一解无需人工验证。因此，正运动学解可直接用于后续计算，无需手动位姿验证。该能力对于作者实验室开发的六自由度材料测试系统至关重要。所开发系统旨在表征增材制造材料在复杂复合多重载荷条件下的性能。通过Stewart Gough平台实际构建运动学的原位标定，实现对移动平台的高精度力控制，从而完成材料表征。