When robot is at singular configuration,the limited hand velocity would require some joints with infeasible speeds so as to lead unsafety of the system.A method of solving the approximate velocity of joint near singular configuration point by adding damped vector is proposed and a modified algorithm is provided.With the analysis of J?,the singular configurations of 6R robot are divided into structure boundary singularity ,boundary singularity ,inner singularity and wrist singularity.The conditions of singularities of the robot have been ascertained.The computer simulations of the singularities of the robot are developed,which have many advantages over previous description methods of the singular configurations of robot.With the help of boundary singularity analysis,a application in welding trajectory planning checking of the robot has been carried out and the simulation result proved visualized and useful.
