# 5720 / Suppress Slip While Crossing Loose Slopes Using Reverse Rotation Behavior Of Rovers With Function Of Independent Contraction/Expansion Mechanism ## Authors Tsukasa Mochizuki, Daisuke Fujiwara, Kojiro Iizuka, Takaaki Sakata, and Tatsuhiko Suga {% hint style="info" %} Paper presented at ISTVS 2024 | 21st International and 12th Asia-Pacific Regional Conference of the ISTVS\ Keywords: Rover; Soft ground; Slip; Sideslip\ {% endhint %} ## Abstract In recent years, many organizations have developed lunar rovers for traveling over uneven terrain. Our research team has studied a rover using independently extending/retracting left and right wheelbases. In the case of four wheels, this method allows three wheels to remain stationary while moving. The independent extending/retracting locomotion of the wheel enables the traction to increase. This method provides a greater support force and improves the climbing performance on a loose slope. However, increased load on a sloped surface causes sideslipping, and the rover tilts its posture in downward. Our previous study confirmed that intentionally increased sinkage by the large wheel slip increased side forces from the soil. However, the lateral force is still insufficient and cause sideslipping on steep slopes. To increase the side force, this study focuses on the resistance between the wheel and the ground, along with the direction of wheel rotation. Specifically, we propose reverse rotation of the upper side wheel of the rover. This method increases dynamic sinkage by increased resistance from the soil during wheel driving. To confirm the effectiveness of method, this study conducts experiments that traversing loose slope with the rover. The results suggest that the proposed method greatly reduces sideslipping. In addition, the results indicated that the wheel sinkage increased. Therefore, the reverse rotation could increase the normal force of the wheels on the upper side. In summary, proposed method increased side forces and suppressed sideslipping. Hence, the reverse rotation prevents tilting the rover’s posture downward on the slope. *** Full paper purchase: \ ISTVS members receive three complimentary papers per year: --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://2024.istvs.org/submissions/papers/5720.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.