Generation and Simulation of Robot Trajectories in a Virtual CAD-Based Off-Line Programming Environment

This paper presents a new approach to the generation and optimisation of the position and orientation trajectories in Cartesian task space, and simulation in a virtual CAD-based off-line programming environment. A novel concept of the robot pose ruled surface is proposed, and defined as a motion locus of the robot orientation vector, i.e. the vector of equivalent angular displacement. The planning for trajectories of robot end-effectors can be accomplished by generating the robot pose ruled surface and optimising its area under the constraints with good kinematics and dynamics performances. The established optimisation model is based on functional analysis and dynamics planning, and is simplified by using high-order polynomial space curves as the robotic position and orientation trajectories. The developed system, RoboSim, is a virtual integrated environment which can be used as a testbed for automatic motion planning and simulation for robots. Two examples are given to verify the feasibility of the proposed approach and models, and to demonstrate the capabilities of generation, optimisation, and simulation modules and libraries in the RoboSim package. The simulation results show that the approach and system are feasible and useful for motion planning, performance analysis and evaluation, and CAD-based prototyping and off-line programming in both the virtual and the real design and planning environment.