## 4 Comparative Simulation Analysis
### Comparative Analysis with DLC  
The changes in vertical velocity of the vehicle body affect vehicle comfort. The changes in the vertical velocity of the front and rear bodies are shown in Figure 8a,b, respectively. Figure 7: Suspension damping mismatch effect. (**a**) Front suspension damping mismatch effect; (**b**) Rear suspension damping mismatch effect. In Figure 8, the prediction curve refers to the prediction curve obtained by the MPC strategy, and the same applies to the prediction curve in Figure 9. Figure 8a indicates that the absolute values of the maximum front body vertical velocity via the MPC and DLC strategies are 0.0178 and 0.0736 m/s, respectively. When compared with the DLC strategy, the MPC strategy shows that the absolute value of the maximum front body vertical velocity dropped by 75.82%. Figure 8b illustrates that the absolute values of the maximum rear body vertical velocity via the MPC and DLC strategies are 0.0158 and 0.0752 m/s, respectively. When compared with the DLC strategy, the MPC strategy shows that the absolute value of the maximum rear body vertical velocity dropped by 78.99%. From the enlarged part of Figure 8, the predicted curve is observed to finally stabilize near the zero value. The changes in vertical velocity of the wheels will affect the comfort of the vehicle. The changes in the vertical velocity of the front and rear wheels are shown in Figure 9a,b, respectively. Figure 8: Changes in the vertical velocity of the vehicle body. (**a**) Vertical velocity of the front body; (**b**) Vertical velocity of the rear body. Figure 9: Changes in the vertical velocity of the wheels. (**a**) Vertical velocity of the front wheel; (**b**) Vertical velocity of the rear wheel. Figure 9 indicates that the changes in vertical speed of the wheels under the two control strategies are basically the same, indicating that the MPC strategy can reduce the vertical velocity of the vehicle body when the vertical velocity of the wheels does not change significantly. As can be seen from the enlarged part of Figure 9, the final value of the wheel vertical velocity prediction curve is also near zero, which verifies the stability of the MPC system. When the dynamic deflection of the suspension exceeds the specified value, the body hits the limit block, and this deteriorates the comfort of the vehicle. Therefore, it is necessary to observe the dynamic deflection of the suspension. The changes in dynamic deflection of the front and rear suspensions are shown in Figure 10a,b, respectively. From Figure 10a, it can be observed that the absolute values of the maximum front suspension dynamic deflection via the MPC and DLC strategies are 0.0112 and 0.0441 m, respectively. When compared with the DLC strategy, the MPC strategy shows that the absolute value of the maximum front suspension dynamic deflection decreased by 74.60%. Furthermore, as can be observed from Figure 10b, the absolute values of the maximum rear suspension dynamic deflection via the MPC and DLC strategies are 0.0050 and 0.0483 m, respectively. When compared with the DLC strategy, the MPC strategy shows that the absolute value of the maximum rear suspension dynamic deflection dropped by 89.65%. Moreover, Figure 6 shows that the MPC strategy reduces the dynamic deflection of the suspension in most of the cases. The change in the pitch angle of the vehicle body will affect the driver's field of vision. The changes in the pitch angle and pitch angle velocity of the vehicle body are shown in Figure 11a,b, respectively. Figure 10: Suspension dynamic deflection. (**a**) Front suspension dynamic deflection; (**b**) Rear suspension dynamic deflection. As can be observed from Figure 11, the absolute values of the maximum body pitch angle via the MPC and DLC strategies are 0.0088 and 0.0347 rad, respectively. When compared with the DLC strategy, the MPC strategy shows that the absolute value of the maximum body pitch angle dropped by 74.64%.