Real-time dynamic trajectory optimization

This paper describes a trajectory optimization system that improves a vehicle's trajectory in real time, as the vehicle moves along it. Using this system, the vehicle begins moving as soon as a feasible, though non-optimal, trajectory is created. As the vehicle moves, the portion of the trajectory that has not been traversed is improved. A framework that allows the trajectory to be improved in real time while maintaining the continuity of the trajectory is presented. The parameter optimization system used to perform the dynamic optimization is discussed. The benefits of the real-time optimization system are demonstrated with experimental results from a thruster propelled air-cushion vehicle. It is shown that for maneuvers in a predictable environment, the real-time optimization system provides at least a 30 percent increase in performance compared to an online trajectory optimization system. In addition to improved performance in a predictable environment, it is shown that the real-time optimization system can compensate for unforeseen changes that occur while the vehicle is in motion. This capability is experimentally demonstrated by efficiently intercepting an evading target vehicle in an obstacle field, a task that would have been impossible without the real-time optimization system. (Author)