四輪車輛動態模型的建立與轉向行為分析

Development of the Dynamic Model of a Four-wheel Vehicle and Analysis of its Steering Behavior

李振廷(Zhen-Ting Lee)

指導教授 ： 蘇偉儁

國立臺灣大學/工學院/機械工程學研究所/碩士(2020年)

https://doi.org/10.6342/NTU202003749

摘要

本研究針對四輪轉向車輛建立模型並進行驗證與分析，對於四輪阿克曼轉向模式的車輛在轉向過程中的轉向性能與穩定性與操控性不足的地方進行改善。首先本研究考慮車輛在各座標軸上的運動並建立車輛動態方程式，並利用Matlab與simulink等分析軟體建立與驗證車輛動態模型，並利用數值分析的方法針對不同轉向路徑，包含J-Turn轉向路徑與車道變換路徑等，調配最佳的後輪轉角輸入、推進力矩輸入、懸吊彈簧剛性等車輛條件，並與原四輪阿克曼轉向模式的車輛輸入進行比較，印證數值分析方法求得的車輛輸入條件能夠改善側滑角響應較大、車身偏擺角速度響應不穩與延遲等問題。在懸吊彈簧剛性調配上，定義評估懸吊穩定度的方式，並分析四輪轉向車輛在統一懸吊彈簧剛性與個別懸吊彈簧剛性調配下的優劣，分析在不同轉向需求的路徑上最佳彈簧剛性調配的模式，並利用數值分析法求得最佳的四輪各自的彈簧剛性。

關鍵字

四輪獨立轉向 ； 四輪驅動 ； 懸吊系統 ； 推進力矩調配 ； 彈簧剛性調配 ； 穩定性

並列摘要

This research analyzes a four-wheel steering car and improves the stability and handling of vehicles with four-wheel Ackerman steering. First, we establish the dynamic equations of the vehicle. Second, we use Matlab and Simulink to build and verify the dynamic model of vehicle. This research uses numerical analysis methods for different steering paths, including J-Turn steering path and single-lane-change path, etc. Third, we adjust the rear wheel angle, suspension spring coefficient and torque. Then, we compare the results with those of four-wheel Ackerman steering. It can be confirmed that the optimized input improves the problems of side slip angle response, unstable and delayed response of the yaw rate. Finally, we evaluate stability of suspension, and adjusts the best spring coefficient of suspension in different car paths by using numerical analysis.

並列關鍵字

four-wheel independent steering ； four-wheel driving ； suspension ； torque velocity ； spring coefficient adjustment ； stability

參考文獻

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