用数据和物理模型结合,让越野车在可变形地形上实现精准预测控制。
Koopman Operator Framework for Modeling and Control of Off-Road Vehicle on Deformable Terrain
- 基于模拟数据构建线性化柯普曼系统,融合物理规律与实测信息。
- 短时预测精度稳定,在轻微地形起伏下仍具鲁棒性。
- 适合需要高精度轨迹跟踪的自主越野车辆控制场景。
本文提出一种混合物理驱动与数据驱动的建模框架,用于自主越野车辆在可变形地形上的预测控制。传统高保真土壤力学模型计算成本过高,难以直接用于控制设计。现代柯普曼算子方法可将复杂的土壤力学与车辆动力学转化为线性形式。本研究通过车辆在可变形地形上的仿真数据,构建柯普曼线性系统:土壤力学采用Bekker-Wong理论建模,车辆简化为五自由度(5-DOF)系统。利用递归子空间识别法,从沙质黏土和黏土的大量仿真数据中识别柯普曼算子,以格拉斯曼距离筛选关键数据片段。该方法优势在于:从仿真学习的柯普曼算子可无缝接入真实系统数据进行更新,形成混合物理-数据驱动范式。预测结果表明,在轻微地形高度变化下具有稳定的短时精度与鲁棒性。嵌入约束型模型预测控制(MPC)后,所学预测器可实现激进操控下的稳定闭环跟踪,且满足转向与扭矩限制。
原文摘要 · Abstract (English)
This work presents a hybrid physics-informed and data-driven modeling framework for predictive control of autonomous off-road vehicles operating on deformable terrain. Traditional high-fidelity terramechanics models are often too computationally demanding to be directly used in control design. Modern Koopman operator methods can be used to represent the complex terramechanics and vehicle dynamics in a linear form. We develop a framework whereby a Koopman linear system can be constructed using data from simulations of a vehicle moving on deformable terrain. For vehicle simulations, the deformable-terrain terramechanics are modeled using Bekker-Wong theory, and the vehicle is represented as a simplified five-degree-of-freedom (5-DOF) system. The Koopman operators are identified from large simulation datasets for sandy loam and clay using a recursive subspace identification method, where Grassmannian distance is used to prioritize informative data segments during training. The advantage of this approach is that the Koopman operator learned from simulations can be updated with data from the physical system in a seamless manner, making this a hybrid physics-informed and data-driven approach. Prediction results demonstrate stable short-horizon accuracy and robustness under mild terrain-height variations. When embedded in a constrained MPC, the learned predictor enables stable closed-loop tracking of aggressive maneuvers while satisfying steering and torque limits.
Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。