本研究是以大型電動巴士為車輛安全控制的討論對象，此巴士與一般的車輛架構不同，並不是單一個驅動引擎的配置，而是搭載了八個馬達，此配置方式能讓每個輪子具有獨立驅動與轉向的能力，利用這樣的特性可以提升車輛駕駛的穩定性並達到安全控制的目的。
車輛行駛時，車身狀態會隨著駕駛情境而有所改變，並不是固定的數值，當車輛動態在急迫操控的情境下，如：高速轉彎時會發生側滑現象，此現象會影響車輛的偏航穩定程度，可能會導致車身狀態偏離線性模型過多，而依據線性模型設計的控制器是否仍能穩健的達成控制目的仍有待釐清。雖然大型巴士車輛的翻覆現象是一個很重要的議題，但是本研究並未探討，本研究只採用後輪轉向作為改善偏航平面穩定的控制手段，進而做到車輛安全的控制目的。以LQ控制作為提升車輛安全的初期設計之控制方法，將後輪轉向角做為控制輸入，其中，透過觀察車輛動態的參數變化來確定偏離線性模型的影響程度，因此嘗試以SDLQ作為解決方案來提高車輛的安全與穩定性。此方案的作法是讓控制器接收當下的車身狀態，並依循新的狀態，去算出符合新狀態的控制命令。研究中，透過線性模型與TruckSim軟體分析比較，探討如何設計控制器與模擬。透過後輪轉向控制，在某些趨於臨界操控的情況下，驗證SDLQ的車輛動態表現是否會比LQ控制具備更好的車輛偏航穩定性，其結果表示在濕滑的情況下，SDLQ會比LQ更能夠去抑制偏航平面的極值數值，但是整體表現與LQ無異。
為了觀察實際的控制器表現，由於現實層面的考量，無法以實際的巴士車輛來進行測試，因此整備了一縮小比例約1/3且具備四輪獨立驅動、轉向功能之電動車實驗平台，但是要獲得車子的側向速度分量是困難的，需要在空曠無遮蔽的場地使用高精度的全球定位系統(GPS)的感測模組搭配慣性感測模組(IMU)，才有辦法獲得。然而，在本校校園內，此量測並不容易進行，目前整備了直流馬達控制以及控制器的能並驗證了所需要的感測器的感測功能。

This research is based on electric bus as the vehicle safety control discussion object. This bus is different from the general vehicle architecture. It is not a single engine configuration, but is equipped with eight motors. This configuration allows each wheel to have The ability of independent driving and steering can improve the stability of vehicle driving and achieve the purpose of safety control.
When the vehicle is running, the vehicle state will change with the driving situation, and it is not a fixed value. When the vehicle dynamics is in a situation of urgent control, such as: sideslip phenomenon occurs when turning at a high speed, this phenomenon will affect the deviation of the vehicle, and may cause the vehicle state to deviate too much from the linear model, and it remains to be clarified whether the controller designed based on the linear model can still achieve the control objective steadily. Although the overturning phenomenon of large buses is a very important topic, this research did not discuss it. This research only uses rear-wheel steering as a control method to improve the stability of the yaw plane, thereby achieving vehicle safety control purposes. LQ control is used as the control method of the initial design to improve vehicle safety, and the rear-wheel steering angle is used as the control input. Among them, the degree of influence of deviation from the linear model is determined by observing the parameter changes of vehicle dynamics. Therefore, SDLQ is tried as a solution. To improve the safety and stability of the vehicle. The method of this scheme is to let the controller receive the current body state and follow the new state to calculate the control command that meets the new state. In the research, through the analysis and comparison of the linear model and TruckSim software, how to design the controller and simulation is discussed. Through the rear-wheel steering control, in certain situations that tend to be critical, it is verified whether the dynamic performance of the SDLQ vehicle will have better vehicle yaw stability than the LQ control. The result indicates that in the case of wet and slippery, SDLQ will It can suppress the extreme value of the yaw plane better than LQ, but the overall performance is no different from LQ.
In order to observe the actual controller performance, due to practical considerations, it is impossible to test with actual buses. Therefore, an electric vehicle experimental platform with a scale down about 1/3 and four-wheel independent driving and steering functions has been prepared. It is difficult to obtain the lateral velocity component of the car, and it is necessary to use a high-precision global positioning system (GPS) sensing module with an inertial sensing module (IMU) in an open and unobstructed venue. However, this measurement is not easy to perform on the campus of our school. At present, the DC motor control and controller functions have been prepared and the sensing function of the required sensor has been verified.

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