Large-span Cable-Driven Parallel Robot

An application scheme of a planar cable-driven parallel manipulator (CDPM) for cleaning the side nets of the deep sea fishing ground (DSFG) was proposed. The object CDPM has three degrees of freedom (DOFs) driven by four cables. The rotational DOF is redundant and used to improve the cable force distribution of the CDPM. First, the method of solving the cable forces is clarified by statics. Then, the standard deviation of the cable forces is used to evaluate the cable force distribution. The orientation angle of the CDPM is optimized to minimize the standard deviation of cable forces. Further, the orientation workspace of the CDPM is determined to constrain the range of angle values in the optimization process considering the orientation continuity of the end effector. Finally, the simulation results show that the uniformity of the cable forces is improved considerably after the orientation optimization, which is beneficial to improve the rigidity and stability of the CDPM. The established optimization method of improving the cable force distribution and performance via redundant DOF can be further adopted to other CDPMs.

With the development of cities, more high-rise buildings continue to emerge. Regular cleaning of building exterior walls is necessary, which mainly relies on manual work now. In this article, the planar four-cable-driven parallel robot (CDPR) is adopted to carry out the external cleaning of high-rise buildings. Firstly, the kinematic model and static model are established. The influence of the maximum cable force on the workspace is analyzed, and the position of the cable connection points on the end effector is discussed. Then, the stiffness of the CDPR is analyzed, which reveals that a large difference of the width-to-height ratio between the end effector and the base improves the stiffness condition number and average stiffness of the CDPR. Considering the size of the cleaning module, the horizontal cross layout is adopted and cable connection points are determined. The cable force range is discussed considering the variable size of the base. Finally, the prototype of a cable-driven cleaning robot is designed accordingly.

Coming soon^^

Coming soon^^