GOALI Collaborative Research: Analytical Modeling and Experimental Analysis of Tires under Uncertain Intrinsic and Operational Parameters

该项目针对复杂的非线性机械系统，如地形车辆和充气轮胎，在其运行环境的背景下进行建模，具有挑战性的方面。在这项研究的范围内，我们将开发一个分析和计算框架，以便在存在参数和外部不确定性的情况下有效地对此类系统进行建模。具体地说，我们将开发方法来准确地表示运行环境和车辆与地形的相互作用。此外，我们将利用高端技术进行实验研究，以分析轮胎与地面接触的物理现象，并验证所开发的建模技术。为了实现现实的性能预测，多体动力学模型必须考虑由于未知环境参数和快速变化的力函数而产生的不确定性。本项目将使用多项式混沌展开来模拟具有参数和外部不确定性的多体动力学系统。该方法适用于高度非线性系统，计算效率高，能处理较大的不确定性。越野车为所提出的理论和实验工作提供了丰富的试验台。他们的性能预测需要车辆、轮胎和地形的准确模型，所有这些都受到不确定性的影响。该项目将从土壤与行驶车辆的动态相互作用的角度对土壤进行建模，并将为难以预测的土壤特性开发随机模型。我们还将使用多步随机技术来模拟粗糙的地形轮廓，它不会强加不切实际的假设，并且可以无缝地纳入车辆运行环境模型中。此外，这项研究将探索创新的分析方法，以开发计算效率高的越野轮胎模型。所开发的理论和计算工具将极大地推动多体动力学领域超越目前的确定性范式，并将使适当的控制策略的开发成为可能。这些工具不是特定于领域的，也可以应用于自动驾驶车辆、工业机械手、执行器和人体建模。

This project addresses challenging aspects in modeling complex nonlinear mechanical systems, such as terrain vehicles and pneumatic tires, in the context of their operating environment. Within the scope of this study we will develop an analytical and computational framework to efficiently model such systems in the presence of parametric and external uncertainty. Specifically, we will develop methods to accurately represent the operating environment and the vehicle-terrain interaction. Moreover, we will conduct experimental studies using high-end technology to analyze the physical phenomena at the tire-terrain contact, and to validate the modeling techniques developed.For realistic performance predictions multibody dynamic models must account for uncertainties resulting from poorly-known environment parameters and rapidly-changing forcing functions. This project will employ the polynomial chaos expansion to simulate multibody dynamic systems with parametric and external uncertainties. This method is applicable to highly nonlinear systems, is computationally efficient, and can handle large uncertainties. Off-road vehicles represent a rich test-bed for the theoretical and experimental work proposed. Their performance prediction requires accurate models of the vehicle, the tire, and the terrain, all of which are affected by uncertainties. This project will model the soil from the standpoint of its dynamic interaction with a running vehicle, and will develop stochastic models for hard-to-predict soil characteristics. We will also employ a multi-step stochastic technique to simulate a rough terrain profile which does not impose unrealistic assumptions, and can be seamlessly incorporated in the vehicle-operating environment model. Further, the study will investigate innovative analytical methods to develop computationally efficient off-road tire models. The theoretical and the computational tools developed will significantly advance the field of multibody dynamics beyond the current deterministic paradigm, and will enable the development of appropriate control strategies. These tools are not domain specific and can also be applied to autonomous vehicles, industrial manipulators, actuators, and human body modeling.