The dynamic traction force in Figure 1 indicates that the vehicle can generate forward motion. Further, based on the differential equation of the vehicle’s motion, the displacement, velocity, and acceleration of the vehicle when it is trapped can be obtained, as shown in Figure 2.
From the displacement curve in Figure 2a, it can be seen that the vehicle displacement increases in a step wise manner, indicating that in the case of unilateral wheel slip, the vehicle can move forward and gradually get out of the trap.
Figure 2b shows the speed and acceleration curves of the vehicle, where the speed curve is pulsating and has zero values, indicating that the vehicle is moving discontinuous and alternating between stationary and forward.
The acceleration of vehicles in motion also has time-varying characteristics, but the acceleration is continuously changing and will produce a certain degree of flexible impact on the vehicle and passengers, without rigid impact.