Traction Control of Planetary Rovers on Soft Terrain Based on the Actuation Margin

The planetary rovers are important devices in nowadays planetary exploration missions. However, the uneven and soft terrain on Lunar and Martin surfaces is challenging to the rovers and leads to hazards in extreme situations. This paper proposes an index of Actuation Margin. It can indicate a wheel’s residual ability of generate traction which is influenced by both terrain physical features and normal load situation. Based on such an index, a traction control method is proposed for planetary rovers. By the allocation of wheel force conditions, the excessive slippage is avoided and the maximum traction ability is increased. Therefore, the proposed method realizes the adaptation of terrain physical features and improves the rover mobility in extreme terrain which is uneven and soft. The proposed control algorithm is applied to a rover prototype and validated experimentally.