Mobility control is one of the most essential parts of planetary rovers’ research and development. The goal of this research is to let the planetary rovers be able to achieve demand of motion from upper level with satisfied control performance under the rough and deformable planetary terrain that often lead to longitudinal slip. The longitudinal slip influences the mobility efficiency obviously, especially on the major deformable slopes. Compared with the past works on normal stiff terrains, properties of soil and interaction between wheels and soil should be considered additionally. Therefore, to achieve the final goal, in this paper, wheel-soil dynamic model for six-wheel planetary rovers while climbing up deformable slopes with longitudinal slip is first built and control based in order to account for slip phenomena. These latter effects are then taken into account within terramechanics theory, relying upon nonlinear control techniques; finally, a robust adaptive fuzzy control strategy with longitudinal slip compensation is developed to reduce the effects induced by slip phenomena and modeling error. Capabilities of this control scheme are demonstrated via full scale simulations carried out with a six-wheel robot moving on sloped deformable terrain, whose real time was computed relying uniquely upon RoSTDyn, a dynamic software. 1. Introduction In the field of special mobile robots environment, including planetary exploration missions, caravan survey, polar expedition, and wild fire spreading, rovers may need to traverse on deformable terrains, and the interaction between rigid wheels and soft soil has become a meaningful research topic because of longitudinal slip influence mobility control obviously [1]. In the past works on normal stiff terrains, for example, Kanayama et al. [2] proposed a stable control scheme for an autonomous mobile robot under the assumption of perfect velocity tracking. Kim and Oh [3] proposed a modified input-output linearization method to solve the problem of a decoupling matrix using a generalized inverse that provided a least-squares solution to the tracking control of two-wheeled mobile robots. Raibert et al. [4] proposed a PID controller to solve the path tracking problem of a mobile robot using a simple linearized model of the mobile robot, which was composed of an integrator and a delay. Colombano et al. [5] proposed an output-feedback controller that allowed a unicycle mobile robot to track a predefined path. However, all of these control methods based on normal stiff terrains hypothesis of nonholonomic mobile robot
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