6.1 結論
本研究考慮側向、橫擺與側傾方向動態設計四輪轉向控制系統，使車輛在緊急駕駛 情況行駛時，保持低側滑角避免車子打滑，加入橫擺角速度參考模型，使車輛橫擺角速 度跟隨給定的參考軌跡，保持車子轉向能力，在物理限制部分本研究採用 RI 物理限制，
考慮到車輛參數以及行車時車輛狀態的影響，合理地限制橫擺角速度參考值以防止車輛 翻覆，同時避免降低車輛之操控性，
在第五章中利用了 CarSim 軟體來進行模擬，並以市場上佔有率越來越高的 SUV 車 型作為模擬平台，由 5.1 節與 5.2 節緊急駕駛情況的模擬中，可以發現本研究所提之控 制器皆可以有效率地利用前後輪側向力達成轉向，並使車輛保持穩定地行駛，對駕駛者 行車安全有顯著的提升，最後由 5.3 節的模擬，以通過 ISO3888-1 測試驗證本研究所提 出之四輪轉向控制系統的效能。
6.2 未來展望
本研究所設計的四輪轉向控制系統於 CarSim 模擬平台上可以得到不錯的效果，但 仍有許多地方需要改進。
本研究是以線性輪胎模型建立 3DOF 車輛模型，利用此線性車輛模型為基礎設計控 制器，其假設縱向速度為固定且角度為小角度的情況，未來可考慮縱向速度為時變，以 及加入輪胎參數為非線性關係之輪胎模型去進行車輛性質分析與設計控制器，可以降低 模型不準確性的影響，提升控制效能。
在參考模型的部分，本研究是採用一般線性參考模型，未來可藉由探討不同的駕駛
情境，例如行駛在一般市區、高速公路或是緊急避障的情況，設計適應性參考模型，藉 由回授車輛動態設計適應法則，調整參考模型參數使車輛能在不同的行車情形展現不同 的操控特性，使四輪轉向車輛發揮更大的效能提高駕駛者安全性與舒適度。
參考資料
[1] J. Seok-Hwan, P. Yong-Jin, H. Chang-Soo, “A Control of Vehicle Using Steer-By-Wire System with Hardware-In-The-Loop-Simulation System”, Proceeding of the IEEE/ASME International Conference on Advanced Intelligent Mechatronics, pp. 389-394, South Korea, July 2003.
[2] http://mobile.autonet.com.tw/cgi-bin/file_view.cgi?a7081338070903
[3] http://www.mingpaofun.com/autonet/article.cfm?aid=378&cid=3&loc=tor [4] http://www.trademag.org.tw/News.asp?id=602291
[5] “New NHTSA Report Shows Federal ESC Requirement Saving Lives”, NHTSA 33-12, Friday, November 30, 2012.
[6] J. Kang, J. Yoo, K. Yi, ” Driving Control Algorithm for Maneuverability, Lateral Stability, and Rollover Prevention of 4WD Electric Vehicles With Independently Driven Front and Rear Wheels”, IEEE Transactions on Vehicular Technology, vol. 60, no 7, pp. 2987-3001, September 2011.
[7] R. Marino, F. Cinili, “Input-Output Decoupling Control by Measurement Feedback in Four-Wheel-Active-Steering Vehicles”, Proceedings of the 45th IEEE Conference on Decision and Control, pp.1717-1720, San Diego, CA, USA, December. 2006.
[8] J. Ahmadi, A. Khaki-Sedigh, M. Kabganian, “Adaptive Vehicle Lateral-Plane Motion Control Using Optimal Tire Friction Forces with Saturation Limits Considerations”, IEEE Transaction on Vehicle Technology, vol. 58, no. 8, pp. 4098-4107, October. 2009.
[9] Y. Shibahata, K. Shimada, T. Tomari, “Improvement of Vehicle Maneuverability by Direct Yaw Moment Control”, Vehicle System Dynamics, vol. 22, pp. 456-481, 1993.
[10] T. Eguchi et al., “Development of ‘Super Hicas’, “A New Rear Wheel Steering System
[11] V. Nikzad. S, M. Naraghi, “Optimizing Vehicle Response in A Combined Ride and Handling Full Car Model By Optimal Control Strategies”, SAE 2001-01-1581, 2001.
[12] J.C. Whitehead, “Four Wheel Steering: Maneuverability and High Speed Stabilization”, SAE Paper 880642, pp. 688-679, 1988.
[13] S. Wang, J. Zhang, “Performance Analysis of 4WS Vehicle Based on Different Control Strategy”, Control and Decision Conference, pp. 5401-5404, NJ, USA, 2009.
[14] 施偉仁，”應用適應性參考模型於四輪轉向車輛側向控制”，國立交通大學，碩士論 文，2011。
[15] C.E. Beal, J.C. Gerdes, “Predictive Control of Vehicle Roll Dynamics with Rear
Wheel Steering”, American Control Conference, pp. 1489-1494, Baltimore, MD, USA, June 30-July 02, 2010.
[16] K. Nam, S. Oh, H. Fujimoto, Y. Hori, “Direct Roll Moment Control for Electric Vehicles Based on Roll Angle Observer and Lateral Tire Force Control”, 8th International Conference on Power Electronics – ECCE Asia, pp. 2681-2686, Korea, May 30-June 3, 2011.
[17] S. Kidane, R. Rajamani, L. Alexander, P. Starr, M. Donath, “Experimental Investigation of a Narrow Leaning Vehicle Tilt Stability Control System”, 2007 American Control Conference, pp. 1612-1617, New York City, USA, July 11-13, 2007.
[18] H. Imine, LM. Fridman, T. Madani, “Steering Control for Rollover Avoidance of Heavy Vehicles”, IEEE Transaction on Vehicle Technology, vol. 61, no. 8, pp. 3499 – 3509, October 2012.
[19] J.R. Ellis, Vehicle dynamics, London, United Kingdom: London Business Book Limited, 1969.
[20] http://www.systemaccess.com.tw/front/bin/ptdetail.phtml?Part=Z27&Category=100087 [21] R. Rajamani, Vehicle Dynamics and Control, New York: Springer-Verlag, pp 15-47,
2006.
[22] J. Yoon, D. Kim, K. Yi, “Design of a rollover index-based vehicle stability control scheme”, Vehicle Syst. Dyn., vol. 45, no. 5, pp. 459-475, May 2007.
[23] A. Bemporad, M. Morari, “Robust model predictive control: A survey”, in Robustness in Identification and Control, New York: Springer-Verlag, pp.207-226, 1999.
[24] A.A. Jalali, V. Nadimi, “A Survey on Robust Model Predictive Control from 1999-2006”, in Proceedings of the International Conference on CIMCA-IAWTIC, pp.
207-212, November 2006.
[25] C.C. MacAdam, "Application of an Optimal Preview Control for Simulation of Closed-Loop Automobile Driving", IEEE Transactions on Systems, Man, and Cybernetics, vol. 11, no. 6, pp. 393-399, June 1981.
[26] C.C. MacAdam, "An Optimal Preview Control for Linear Systems", Journal of Dynamic Systems, Measurement, and Control, ASME, vol. 102, no. 3, pp.188-190, September 1980.