A Systematic Method Based on Coupling-Degree for Solutions to Forward Displacement Analysis of 6-SPS Parallel Mechanisms

Hui-Ping Shen ； An-Xin Liu ； Xiao-Rong Zhu ； Yan-Ling Lu ； Ting-Li Yang

《Proceedings of the 14th IFToMM World Congress》 14th-1 (2015/10) Pp. 254-263

https://doi.org/10.6567/IFToMM.14TH.WC.OS2.017

並列摘要

Relation between the complexity of mechanism topological structure and the difficulty level of mechanism forward displacement analysis is revealed. A systematic method for finding all real forward displacement solutions of 6-SPS parallel mechanisms based on coupling-degree k is proposed. Detail contents of this paper include: (1) Six basic types of 6-SPS parallel mechanisms are classified into 4 categories based on their coupling-degree k values, i.e. k=0, 1, 2 and 3. (2) A systematic method is proposed for forward displacement analysis of 6-SPS parallel mechanisms. For element mechanism (k=0), the analytical forward solutions can be obtained very easily，which is then used as the basis for forward analysis of 6-SPS parallel mechanisms with k=1 to 3. For 6-SPS parallel mechanism with k=1 to 3, the 6-SPS parallel mechanism can first be converted into an element mechanism by virtually adding k SPS branches and k compatibility equations (each with only one variable) can then be established based on link-length constraint conditions. Then all real solutions to the forward displacement analysis can be obtained via k-dimensional search algorithm. (3) Procedures of the k-dimensional search methods for finding all real forward solutions of 6-SPS parallel mechanisms with k=1 to 3 are described in detail and several numerical examples are provided for illustration purpose.

並列關鍵字

Parallel mechanism ； Coupling degree ； Forward ； Displacement analysis ； 6-SPS parallel mechanisms