Abstract：The traction force of wheeled horizontal-well tractors is mainly produced by the contact between the wheels and the pipe walls. Previous studies ignored the plastic deformation caused by the contact between the wheels and the walls and used empirical friction coefficients to model the forces, which has led to significant errors. This paper derives a wedge indentation model (the wedge symmetry axis is perpendicular to the pipe wall) based on the simultaneous action of the normal force and the torque to predict the indentation formation according to slip line theory. Finite element analysis results not only show the plastic deformation for various forces, but also verify the quantitative relationship between the forces and the indentation shape. Comparisons with measured indentation shapes shows that the theoretical model can predict the indentation depth and the pile-up height, which can be used to improve sideling indentation modeling of wheels for better traction modeling.
常旭, 杨东超, 孙可平, 朱衡, 杨淇耀. 爬行器驱动轮正压过程分析[J]. 清华大学学报（自然科学版）, 2019, 59(7): 537-543.
CHANG Xu, YANG Dongchao, SUN Keping, ZHU Heng, YANG Qiyao. Analysis of the normal indentation process caused by tractor wheels. Journal of Tsinghua University(Science and Technology), 2019, 59(7): 537-543.
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2019, Vol. 59 
