科创中国

原文链接：万方

• 摘要：

  The compliance modeling and rigidity performance evaluation for the lower mobility parallel manipulators are still to be remained as two overwhelming challenges in the stage of conceptual design due to their geometric complexities. By using the screw theory, this paper explores the compliance modeling and eigencompliance evaluation of a newly patented 1T2R spindle head whose topological architecture is a 3-RPS parallel mechanism. The kinematic definitions and inverse position analysis are briefly addressed in the first place to provide necessary information for compliance modeling. By considering the 3-RPS parallel kinematic machine(PKM) as a typical compliant parallel device, whose three limb assemblages have bending, extending and torsional deflections, an analytical compliance model for the spindle head is established with screw theory and the analytical stiffness matrix of the platform is formulated. Based on the eigenscrew decomposition, the eigencompliance and corresponding eigenscrews are analyzed and the platform's compliance properties are physically interpreted as the suspension of six screw springs. The distributions of stiffness constants of the six screw springs throughout the workspace are predicted in a quick manner with a piece-by-piece calculation algorithm. The numerical simulation reveals a strong dependency of platform's compliance on its configuration in that they are axially symmetric due to structural features. At the last stage, the effects of some design variables such as structural, configurational and dimensional parameters on system rigidity characteristics are investigated with the purpose of providing useful information for the structural design and performance improvement of the PKM. Compared with previous efforts in compliance analysis of PKMs, the present methodology is more intuitive and universal thus can be easily applied to evaluate the overall rigidity performance of other PKMs with high efficiency.

• 关键词：

  compliance modeling parallel kinematic machine eigencompliance eigenscrew

• 作者单位：

  School of Mechanical Engineering, Anhui University of Technology, Ma'anshan 243032, China%Department of Informatics, King's College London, London WC2R 2LS, UK

• 基金项目：

  National Natural Science Foundation of China(Grant51375013)%Anhui Provincial Natural Science Foundation of China(Grant1208085ME64)%Open Research Fund of Key Laboratory of High Performance Complex Manufacturing,Central South University(Grant Kfkt2013-12)%The corresponding author is also thankful to the sponsor of China Scholarship Council(CSC,Grant8260121203065)

• 来源期刊：

  中国机械工程学报

• 年，卷(期)：

  201427004