Real-time operator-in-the-loop simulation of multibody systems

This thesis presents a general approach to achieving real-time operator-in-the-loop simulation for multibody dynamic systems. Emerging real-time dynamic simulation methods are used to demonstrate the potential for creating interactive design workstations and for teleoperating space robots, with a human operator in the control loop. The recursive formulation of multibody system dynamics with relative coordinates is employed for efficient numerical analysis and implementation on parallel computer. High speed computer graphics techniques are employed to create realistic visual cues for the simulator.;A simulator is developed in this research by integrating the real-time dynamics program, a realistic graphics display, and the operator's control interface. Real-time operator-in-the-loop simulation is analyzed, as regards the goal of real clock time, not only with respect to dynamic simulation but also with respect to graphics display and the operator interface. Synchronization of the simulation is found to be most important for realism of the simulator.;A backhoe simulation is implemented to demonstrate the capability for operator-in-the-loop simulation. The simulator is developed by modeling backhoe dynamics and hydraulic systems with the recursive formulation to achieve real-time simulation, developing an interactive graphics program for visual cues, and interfacing the operator's control action with the dynamic simulation through a pair of joysticks. The simulator is also implemented for teleoperated simulation of space robots.