We describe an algorithm that generates a smooth trajectory (position, velocity, and acceleration) for a non-holonomic vehicle autonomously navigating within the constraints of lanes in a road. The technique models both vehicle paths and lane segments as straight line segments and circular arcs for mathematical simplicity and elegance. We use the following approach. Develop the path in an idealized space, warp the path into real space and compute path length, generate a one-dimensional trajectory along the path length that achieves target speeds and positions, and finally, warp, translate, and rotate the one-dimensional trajectory points onto the path in real space. The algorithm moves a vehicle in lane safely and efficiently within speed and acceleration maximums. We also describe how the algorithm functions in the context of other autonomous driving functions within a carefully designed vehicle control hierarchy.
Citation: NIST Interagency/Internal Report (NISTIR) - 7262
NIST Pub Series: NIST Interagency/Internal Report (NISTIR)
Pub Type: NIST Pubs
autonomous vehicle, on-road, on-road autonomous vehicle, radial warping, trajectory generation, vehicle trajectory generation