Planning Feed Trajectory Of Milling Robot Considering Interference And Constraintwith Cable

Industrial robots have been put into use in many fields such as welding,carrying,assembly,milling and so on,because of their high flexibility capabilities.Usually,robots need many end effectors like welding gun,laser,spray gun and milling cutter to achieve different manufacturing functions.Flexible cable is often added to the robot end of the actuator like wire,air pipe,optical fiber and water piper because added end effectors.These processes usually involve complex curves or surface trajectories,which are often inefficient in teaching programming.on the one hand,Offline programming overcame the shortcomings of low efficiency of teaching programming;on the other hand,It will squeeze,intertwine or excessive reverse easily and result in its damage when the robot is running due to the introduction of end effectors,resulting in cable damaged and serious impact on the operation process.Therefore,aimed at the robot off-line programming for replaceable end effectors and considered the impact of the robot trajectory for terminal cable interference,planning reasonable and reliable running track for robot with cable will be significant.In this paper,the 6-DOF milling robot with cable is taken as the object of study,andtook avoiding cable interference and excessive overturn itself in the feed process as the goal,based on the Cartesian space programming method,constructed the Euler angle interpolation model of the robot,and the feed trajectory is optimized by the firefly algorithm.The main contributions are as follows:(1)By analyzing the both ends poses of the cable then researching the flexible cable's status,a trajectory planning of circular interpolation strategy is proposed based on Cartesian space.One of the flexible cable ends fixed and the other end is fixed on the robot end effectors.This strategy can make robot smooth running and reduce the impact and vibration in the same time.Then,adopting linear interpolation for Euler angle of the cable end poses to control the cable both ends poses' difference in a certain range and avoid its excessive reverse.(2)Putting forward a multi-objective trajectory optimization based on firefly algorithm.This method can reduce vibration of robot and improve its working efficiency under the premise of no cable interference.Using the length and smooth oftrack as the optimized object and searching optimal trajectory by the firefly algorithm.(3)Aimed at the Staubli TX90 milling robot system,the simulation and physical experiments are carried out respectively.The multi-objective optimal trajectory method proposed in this paper is verified.The effectiveness of the proposed method is verified by the relevant motion state analysis and data comparison analysis.