Numerical modelling of flexible wheel-soil interaction for planetary rovers

太空探索正在迅速发展，美国宇航局已作出坚定承诺，将在2020年代重返月球，并在2030年代重返火星。这包括提供机器人技术，以支持探索月球、火星、小行星和太阳系其他天体的新任务。这项工作的大部分将需要使用行星漫游者，这是一种设计用于在行星表面移动的自主太空飞行器。底层土壤的机械特性控制着牵引性能，松散的地形可能导致固定，例如火星探测车所经历的。各种车轮-土壤相互作用（地面力学）理论已经开发出来，并已应用于行星车辆自阿波罗计划。为解释土壤-车轮相互作用而增加严格的数值模型，将增加目前可用于流动站设计的技术范围。在这项研究中，有限元软件ABAQUS将被用来开发一个灵活的车轮滚动通过排水土壤介质的有限元模型，这将与现有的单轮土壤实验室试验台数据进行验证。将进行参数研究，以评估车轮尺寸、土壤参数（刚度和强度）、相对车轮-土壤压缩性和界面特性对沉陷和滚动期间土壤-车轮系统变形和应力的影响。这一举措将有助于开发和优化流动站技术，并将帮助该部门应对紧急需求。它将提供更好的理解漫游车车轮技术，这是至关重要的漫游车移动性能评估和整体漫游车设计。

Space exploration is rapidly evolving and NASA has made firm commitments to return to the Moon in the 2020s and Mars in the 2030s. This includes the provision of robotics to support new missions to explore the Moon, Mars, asteroids, and other bodies in the solar system. Much of this effort will require the use of planetary rovers, which are autonomous space vehicles designed to move across a planet's surface. The mechanical properties of the underlying soils control the tractive performance and loose terrain may result in immobilization, such as that experienced by the Mars exploration rovers. Various wheel-soil interaction (terramechanics) theories have been developed previously and have been applied to planetary vehicles since the Apollo program. The addition of rigorous numerical modelling for the interpretation of soil-wheel interaction would increase the current range of techniques for rover design that are available. In this study, the FEM software ABAQUS will be used to develop finite element models of a flexible wheel rolling across a drained soil medium, which will be validated with existing single wheel-soil laboratory test bed data. A parametric study will be conducted to assess the influence of wheel dimensions, soil parameters (stiffness and strength), relative wheel-soil compressibility and interface properties on deformation and stresses of the soil-wheel system during sinkage and rolling. This initiative will contribute to the development and optimization of rover technology and will help the sector respond to urgent needs. It will provide better understanding of rover wheel technology, which is vital for rover mobility performance evaluation and overall rover design.