就翻覆預防控制器而言，使用差動煞車(Differential braking)或直接偏航轉矩(Direct Yaw-moment Control, DYC)之控制在近年來備受重視，本研究使用模型預估控制法(model predictive control, MPC)設計DYC，因為MPC對未來系統狀態的預期行為與駕駛人之操控行為類似，相當適合本研究於設計DYC以輔助駕駛人操控所需。然而透過此手段設計控制器時，車輛受到控制器之煞車命令作動後，將會造成縱向速度隨之遞減的問題。速度之改變導致車輛動力學產生顯著的變化，因此於MPC之計算中需考慮受控系統之模型的變化。
本研究於MATLAB/SIMULINK中建立車輛模型、駕駛人模型以及DYC後，進一步討論DYC於四種條件設定下的模擬結果，分別為考慮駕駛人模型存在與否以及更新車速與否，經模擬結果顯示考慮駕駛人模型存在以及具有車速更新能力之DYC設計，不但抑制翻覆角峰值約30%，另外亦有輔助駕駛人進行路徑追蹤之能力；而其他三種條件設定中，不但降低車輛的路徑追蹤能力，亦發生翻覆角有不減反增之情形。
在完成電腦模擬後，本研究並透過縮小型車輛平台進行實驗，透過實際駕駛人控制前輪轉向角以達成雙車道變換之任務，以評估加入DYC抑制翻覆的效果。實驗結果顯示本研究所設計的DYC在車輛進行激烈的車道變換時，仍然輸出合適的偏航轉矩以有效的抑制翻覆動作，亦即達到翻覆預防的效果。

The application of differential braking or direct yaw moment control (DYC) for vehicle roll-over prevention receives increasing attentions in recent years. In this research the model predictive control (MPC) technique is employed to design the DYC for rollover prevention. The predictive nature of the MPC resembles human’s vehicle driving characteristics, and is therefore a intuitive choice for the rollover prevention control design. Due to the braking actions resulted from the DYC, the vehicle longitudinal velocity is reduced, and the reduction in vehicle speed causes significant changes in the vehicle dynamics. Therefore, how to incorporate the variation in speed in the MPC design is investigated in this research, and the modified design is evaluated using computer simulations and experiments with a scaled vehicle.
The vehicle model, driver model, and the DYC are implemented as mathematical models in MATLAB/SIMULINK. The performance of the controller is evaluated by several sets of simulation scenarios, with different choices of driver models and vehicle speed settings. The simulations indicate that with a proper driver steering control model in the loop, and the internal model used in MPC updated on-line with varying speed, the DYC generates the most appropriate rollover prevention actions. The peak value of roll angle is reduced by approximately 30%, while maintaining slight improvement in lateral position tracking. The other choices may result in degradation in lateral position tracking, or even worsen the rollover motion.
The DYC design is also evaluated on a scaled vehicle setup, through a human driver controlling the steering actions. The experimental results indicate that the designed DYC can provide reasonable improvement to rollover prevention under double lane change maneuver.

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