Wrench Capability Analysis of a Cooperative Multi-Unmanned Aerial Vehicle Parallel Robot With Rigid Links

摘要

Abstract The wrench capability analysis of an aerial parallel robot named flying parallel robot (FPR), which involves multiple unmanned aerial vehicles (UAVs) cooperatively supporting a moving platform with rigid links, is investigated in this article. The concept of the available thrust set (ATS) associated with a quadrotor system is introduced, which allows to determine the admissible range of thrust forces generated by a quadrotor actuator given its actuation limits. Under the quasi-static equilibrium condition, the available wrench set (AWS) of the platform is calculated, through the derivation of a wrench matrix that relates the thrust force vectors to the wrench exerted on the platform. A quantitative metric, referred to as capacity margin, is adopted to evaluate the wrench capability of the system with certain robot configurations. The detailed analysis is showcased through several case studies and validated in both ROS simulations and experiments conducted on a real robot.