To improve working efficiency of manipulators

a new time-optimal trajectory planning method is proposed.Series of joint space position corresponding to trajectory in task space are obtained by inverse kinematics operation

and B-splines curves of seven times are used to construct interpolate trajectory of joint space.By converting kinematic constraints to constraints on control points of B-splines trajectory curve

and properly relax constraints

time optimization problem are solved by using trust region method

and then time-optimal and velocity

acceleration and jerk continuous trajectories which satisfy kinematic constraints are planned.Simulation results demonstrate the proposed optimal trajectory planning method is effective.