Resistance coefficient (RC) is an important measure when designing wheel-driving mechanisms and accurate dynamic models for real-time mobility control of wheeled mobile robots (WMRs). This measure is typically formulated as a constant that depends on the wheel load, wheel dimensions, and soil that the WMR is designed for. This article proposes a novel variable RC that responds to terrain deformation. This variable RC is then applied to controllers for WMRs that estimate driving torques and slip ratios on deformable terrain. Simple yet accurate models of RC are developed from both experimental results and theoretical analysis, and these models are then compared with other methods. The proposed RC models give more accurate and more computationally efficient estimations of driving torques and slip ratios for WMRs, with average estimation errors less than 6% and the shortest computation time in experiments. The two proposed estimators are then applied to the design of the tracking-control systems for a WMR running on deformable terrain. Experiments with simulated sandy terrain demonstrate that both proposed control systems are feasible, and the slip estimation effectively decreases velocity tracking errors from more than 20% to less than 10%.

中文翻译：

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变形地形轮式移动机器人变阻系数的定义及应用

阻力系数 (RC) 是轮式移动机器人 (WMR) 实时移动控制设计轮驱动机构和精确动力学模型时的重要度量。该度量通常表示为一个常数，该常数取决于 WMR 设计用于的车轮载荷、车轮尺寸和土壤。本文提出了一种响应地形变形的新型变量 RC。然后将此变量 RC 应用于 WMR 的控制器，以估计可变形地形上的驱动扭矩和滑移率。根据实验结果和理论分析开发了简单而准确的 RC 模型，然后将这些模型与其他方法进行比较。提出的 RC 模型为 WMR 提供了更准确和计算效率更高的驱动扭矩和滑移率估计，平均估计误差小于6%，实验计算时间最短。然后将两个建议的估计器应用于在可变形地形上运行的 WMR 的跟踪控制系统的设计。模拟沙地实验表明，这两种控制系统都是可行的，滑移估计有效地将速度跟踪误差从 20% 以上降低到 10% 以下。