Research On Cable Tension Distribution Algorithm Of Multi-redundant Cable-driven Parallel System

The cable-driven parallel system is a special parallel system driven by cable,which has the advantages of small inertia and fast response.According to the number of cables and degree of freedom of the system,the parallel system driven by cables can be divided into three categories: under-constrained,full-constrained and redundant-constrainted.Because the number of ropes in parallel system with complete and redundant constraints is larger than the number of degrees of freedom,they belong to redundant driven system.Solution of cable tension is a key problem in motion control of cable-driven parallel system.The cable tension of redundant parallel drive system has many solutions,and with the increase of redundant drive number,the difficulty of solving cable tension increases.In this paper,the cable tension distribution algorithm of parallel system driven by multiple redundant cables with redundant driven numbers 2 and 3 is studied.For cable-driven parallel system with redundant driven number of 3,a cable tension distribution algorithm based on intersection of parallel planes is proposed.The algorithm includes two parts: the solution space of cable tension and the optimization of cable tension.Taking a 6-DOF 9-cable-driven parallel system as an example,the cable tension distribution problem is analyzed,and an efficient algorithm for solving the intersection of parallel planes is proposed.The design principle and implementation process of the algorithm are discussed in detail.The minimum two-norm method is used to select the optimal solution space as the cable tension distribution solution.According to the actual operation results of the algorithm,the continuity of the cable tension is verified and the real-time performance of the algorithm is analyzed.For the cable-driven parallel system with redundant driven number of 2,a cable tension distribution algorithm based on the intersection of parallel lines is proposed.The algorithm includes two parts: the solution space of cable tension and the optimization of cable tension.Taking 6-DOF 8-cable-driven parallel system as an example,the cable tension distribution is analyzed,and an efficient algorithm for solving the intersection of parallel lines is proposed.The design principle and implementation process of the algorithm are discussed in detail.The polygon centroid and weighted center of gravity method are used to optimize the cable tension,and the optimal solution space is chosen as the cable tension distribution solution.According to the actual operation results of the cable tension distribution algorithm,the continuity of the cable tension is verified and the real-time performance of the algorithm is analyzed.Two kinds of cable tension distribution algorithms are validated by using MATLAB and ADAMS simulation methods.A virtual prototype of 6-DOF 9-cable-driven and 6-DOF 8-cable-driven parallel system is built.The simulation control program is designed,and the correctness of the two algorithms is verified by setting different conditions.