Robotics: Science and Systems XX

Model Predictive Control for Aggressive Driving Over Uneven Terrain

Tyler Han, Alex Liu, Anqi Li, Alexander Spitzer, Guanya Shi, Byron Boots

Abstract:

Terrain traversability in unstructured off-road autonomy has traditionally relied on semantic classification, resource-intensive dynamics models, or purely geometry-based methods to predict vehicle-terrain interactions. While inconsequential at low speeds, uneven terrain subjects our full-scale system to safety-critical challenges at operating speeds of 7-10 m/s. This study focuses particularly on uneven terrain such as hills, banks, and ditches. These common high-risk geometries are capable of disabling the vehicle and causing severe passenger injuries if poorly traversed. We introduce a physics-based framework for identifying traversability constraints on terrain dynamics. Using this framework, we derive two fundamental constraints, each with a focus on mitigating rollover and ditch-crossing failures while being fully parallelizable in the sample-based Model Predictive Control (MPC) framework. In addition, we present the design of our planning and control system, which implements our parallelized constraints in MPC and utilizes a low-level controller to meet the demands of our aggressive driving without prior information about the environment and its dynamics. Through real-world experimentation and traversal of hills and ditches, we demonstrate that our approach captures fundamental elements of safe and aggressive autonomy over uneven terrain. Our approach improves upon geometry-based methods by completing comprehensive off-road courses up to 22\% faster while maintaining safe operation.

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Bibtex:

  
@INPROCEEDINGS{Han-RSS-24, 
    AUTHOR    = {Tyler Han AND Alex Liu AND Anqi Li AND Alexander Spitzer AND Guanya Shi AND Byron Boots}, 
    TITLE     = {{Model Predictive Control for Aggressive Driving Over Uneven Terrain}}, 
    BOOKTITLE = {Proceedings of Robotics: Science and Systems}, 
    YEAR      = {2024}, 
    ADDRESS   = {Delft, Netherlands}, 
    MONTH     = {July}, 
    DOI       = {10.15607/RSS.2024.XX.022} 
}