在本研究中發展了一套只需利用車輛動態來估測輪胎與地面間摩擦力之估 測方式，且在演算法中分別估測出四個輪胎的縱向力，也使用了摩擦力圓的特性 來求得四個輪胎的側向力，並且也對車輛的不確定參數做估測。在模擬的部分使 用了高階的完整車輛模型模擬真實車輛的駕駛狀況，另外在硬體實驗的部分設計 了可以模擬真實車輛輪胎與地面接觸情形實驗帄台，在利用此實驗帄台進行縱向 力的估測實驗。
在第四章的部份模擬了不同路面情況下 J-turn 與 single lane change 的駕 駛狀況，數據中可以看出此演算確實可以估測出四個輪胎個別的縱向力與側向 力，且不同大小的轉向角下都可以有不錯的估測效果，而且模擬中都有模擬路面 狀況突然改變的情況，數據中也可以明顯的看出估測效果效過並未受到影響，依 然可以估測出摩擦力的變化。為了應對車輛參數不準確的情況，在本研究中也使 用了期望值最大化演算法來進行不確定參數之估測，雖然就模擬結果來看，有部 份的不確定參數並未收斂到正確的數值，但是就摩擦力的估測結果來看，不確定 參數估測的結果並沒有嚴重的影響到摩擦力的估測。在實驗中雖然缺乏了真正可 以量測縱向力的感測器，但是在此利用了輪胎與地面間的滑動比與側向力之關係 式來證明縱向力估測的正確性，分析實驗數據後，也可以發現實驗的結果的確有 符合理論的預測關係，所以也證明了實驗中估測出的縱向力之正確性。
未來工作的部分分成以下兩點陳述：
一、在此做摩擦力的估測時，都假設了車輛四個輪胎同時煞車、同時加速，
也同時進入摩擦係數相同的路面，但是車輛的駕駛有時會出現左右輪進入了不同 摩擦係數的路面下，或是車輛使用了差動式剎車系統，以上兩種狀況都會讓演算
二、在硬體實驗的方面因為缺乏了實際可以量測摩擦力的感測器，所以沒辦 法很直觀的討論估測的正確性，也造成了硬體設施無法與車輛模型互相整合成為 一個 Hardware-in-the-loop 的實驗帄台，因為在側向力的估測實驗需要車輛本 身的動態，而本研究架設的帄台無法模擬真實車輛的轉向，所以只能靠軟體補助 實驗，但是在缺感測器的情況下無法達成此實驗，所以在未來工作會考慮購入感 測器來完成側向力估測的實驗驗證。
附錄一 模擬中所使用的車輛參數：
參數 符號 數值
車體質量 m v 1740kg
質心到前輪輪軸長度 l 1 1.05m
質心到後輪輪軸長度 l 2 1.4m
車輛前輪距離 sb 1 1.65m
車輛後輪距離 sb 2 1.45m
車輛高度 h 0.6m
側傾轉動慣量 I x 420kg m 2
俯仰轉動慣量
Iy 2594kg m 2
橫擺轉動慣量 I z 3480kg m 2
模擬中所使用的懸吊系統參數：
參數 符號 數值
彈簧係數 C 1 34000N/m
彈簧係數 C 2 300N/m
彈簧係數 C 3 0.21N/m
阻泥係數 D N〃s/m
模擬中所使用的輪胎參數：
附錄二
濾波器轉移函數與波德圖：
Filter1~Filter3 與第六章所使用的濾波器：
-1 -2
附錄三 轉動慣量 10 次的實驗結果：
帄均(N m 2) 變異數
實驗一 7.95 1.58
實驗二 8.97 0.95
實驗三 9.23 0.36
實驗四 8.52 0.57
實驗五 8.45 0.43
實驗六 8.63 1.01
實驗七 7.45 2.57
實驗八 7.98 1.22
實驗九 9.63 0.66
實驗十 8.42 1.78
縱向力估測的 15 實驗結果：
轉速訊號 輪胎剛度方程式 相關係數 (最大縱向力(N),s) 3u(t-4) 77.62s-0.654 0.45 (8.54,0.096) 6u(t-4) 82.11s-0.998 0.62 (8.73,0.101) 9u(t-4) 84.32s-0.112 0.73 (8.62,0.101) 4+sin(0.5x2πt) 91.77s-0.852 0.66 (9.54,0.123) 4+sin(2πt) 86.44s-1.001 0.82 (8.84,0.081) 4+sin(1.5x2πt) 77.54s-0.098 0.89 (8.55,0.098)
6+2*sin(0.5x2πt) 96.82s-0.487 0.91 (8.25,0.084) 6+2*sin(1.5x2πt) 89.08s-0.245 0.84 (8.67,0.091) 7+3*sin(0.5x2πt) 79.79s-0.705 0.49 (8.45,0.178) 7+3*sin(2πt) 75.00s-0.520 0.58 (9.64,0.112) 7+3*sin(1.5x2πt) 78.58s-0.707 0.63 (8.72,0.145) 6+sin(0.5x2πt) 85.42s-0.545 0.92 (8.86,0.081) 7+sin(0.5x2πt) 86.68s-0.429 0.87 (9.62,0.102) 9+ sin(0.5x2πt) 85.55s-0.728 0.95 (9.33,0.118)
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