Robot Simulation and Off-Line Programming — An Integrated CAE-CAD Approach

Teaching a robot with traditional on-line programming techniques is a time-consuming process requiring trial-and-error procedures. Furthermore, the on-line method of robot programming requires the use of an actual robot and the entire work cell, in which the robot is physically put through its sequence of actions with equipment mockups and product prototype parts. Interactive computer graphics simulation and off-line programming of robots offer the potential to overcome these limitations and are therefore becoming increasingly important in factory automation, military, and space robotic applications.This paper describes a general purpose computer program for robot kinematic and dynamic simulation that enables a designer to evaluate the performance of robot manipulators in potential working environments. The designer can base evaluation on a time-and-motion study of task performance.The robot modeling capability of the program is generic. The user can interactively create and edit any one- to twelve-axis robot manipulator, articulated or Cartesian. This includes many of the existing industrial robots, plus a variety of prototype robot designs containing up to twelve axes. The robot can have three types of joints: revolute (turning joint), prismatic (sliding joint), and cylindrical (turning and sliding simultaneously). The program has a general purpose kinematic and dynamic analysis algorithm that includes both forward and inverse solutions.Robot off-line programming allows robots to remain on-line performing manufacturing tasks, while being programmed for another job. This makes it easier to specify and develop optimum robot motion paths, permits programming of robots earlier in the product and tooling design cycle, and reduces the safety problems related to robots. Off-line programming of robots will accelerate trends towards fully utilized robot-based flexible manufacturing systems.