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The straw-checkerboard sand barriers paving robot can insert grass to establish Straw-checker sand barriers that prevent wind and fix sand. The robot is used in desert, and the trafficability in desert is the key factor of its properties. Based on the experiments of physical properties of desert sand,，the driving force of running desert wheeled cross-country vehicle were obtained by calculating force between tire and sand. The experiments about pressuring grass resistance of lengthways lay out grass mechanism were done. According to the vehicle terramechanics theory, desert trafficability of straw-checkerboard sand barriers paving robot was analyzed. The theoretical and experimental results showed that the robot has outstanding trafficability in desert.