Abstract Wheeled vehicle mobility on loose sand is highly subject to shear deformation of sand around the wheel because the shear stress generates traction force of the wheel. The main contribution of this paper is to improve a shear stress model for a lightweight wheeled vehicle on dry sand. This work exploits two experimental approaches, an in-wheel sensor and a particle image velocimetry that precisely measure the shear stress and shear deformation generated at the interaction boundary. Further, the paper improves a shear stress model. The model proposed in this paper considers a force chain generated inside the granular media, boundary friction between the wheel surface and sand, and velocity dependency of the friction. The proposed model is experimentally validated, and its usefulness is confirmed through numerical simulation of the wheel traction force. The simulation result confirmed that the proposed model calculated the traction force with an accuracy about 70%, whereas the conventional one overestimated the force, and its accuracy was 13% at the best.

中文翻译：

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基于轮内传感器和粒子图像测速的轮-土相互作用力学实验研究第二部分。轻型轮式车辆剪应力分析与建模

摘要 轮式车辆在松散沙土上的机动性极易受到车轮周围沙土的剪切变形的影响，因为剪切应力会产生车轮牵引力。本文的主要贡献是改进干沙上轻型轮式车辆的剪应力模型。这项工作利用了两种实验方法，轮内传感器和粒子图像测速仪，可精确测量相互作用边界处产生的剪切应力和剪切变形。此外，该论文改进了剪切应力模型。本文提出的模型考虑了颗粒介质内部产生的力链、车轮表面和沙子之间的边界摩擦以及摩擦的速度依赖性。所提出的模型经过实验验证，并通过车轮牵引力的数值模拟证实了其有用性。仿真结果证实，所提出的模型计算牵引力的准确度约为70%，而传统的模型高估了牵引力，其准确度最高为13%。