貨車在不同載重時之阻尼調配

Damping Coefficients Adjustment for a Truck under Various Loading Conditions

廖彥欣(Yan-Sin Liao)

指導教授 ： 劉霆

國立臺灣大學/工學院/機械工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.10023

摘要

載貨貨車載重變化大，配合適當的阻尼調配，可有效提高駕駛乘適性。本研究欲針對載重變化大的載貨貨車提供一套簡便的阻尼調配法，探討調配之方法及效果，並提出可行調配方法，包括手動調整阻尼值，半自動依車速調整阻尼值，自動調整阻尼。其中自動調整係利用量測車體加速度均方根值的方式來判別載重狀態，並依據當前載重狀態以及行車速度給予適當的前後阻尼係數，增進駕駛乘坐舒適性。首先建立七自由度全車模型，利用D’Alembert方程式建立系統之運動方程式，並且介紹頻域響應、隨機路面振動響應的理論推導以及模擬方法和結果。接著用上述分析方法探討阻尼對於車輛動態特性的影響，並且利用隨機路面振動響應進行阻尼係數的調配與車輛動態特性變化之間關係之探討。最後，發展一套阻尼調配方法，並將結果與預設阻尼相較，了解調整阻尼後對駕駛乘適性所帶來的助益以及所能達到的效果。

關鍵字

貨車 ； 加速度均方根值 ； 阻尼係數 ； 七自由度全車模型 ； 隨機路面

並列摘要

It is effective to improve the ride comfort for trucks with variable loading by operating appropriate adjustment of damping coefficients. This study provides a simple strategy of damping coefficients adjustment aimed to trucks with variable loading. Discuss the methods of adjustment and the effects, and provide feasible adjustment strategy including manual, semi-auto by vehicle speed and auto adjustment of damping coefficient. The active adjustment strategy determines the loading condition by measuring acceleration root mean square values of the vehicle body, and then gives appropriate front/rear damping coefficients according to the current loading condition and ground speed of the vehicle to improve the ride comfort of passengers. Firstly, a 7-DOF vehicle model is introduced, and the equations of motion of the system are established by using D’Alembert principle. Then, introduce the theories of frequency response and random vibration response of the system. The above different motion responses are used to investigate the effect of damper on vehicle dynamics, and the random vibration response is selected to study the adjustment of damping coefficients on vehicle ride and handling dynamic characteristics. Finally, this study develops a strategy of damping coefficients adjustment.

Furthermore, comparing the adjusted result with that of default, it helps to illustrate that the damping coefficients adjustment can boost the ride comfort and to show the effect it can achieve.

並列關鍵字

Truck ； Acceleration root mean square ； Damping coefficients ； 7-DOF vehicle model ； Random vibration

參考文獻

[8] 廖家慶，『車輛乘適性能分析與驗證』，國立臺灣大學機械工程研究所碩士論文，中華民國九十四年。

[13] 楊智麟，『簧下質量對車輛懸吊動態性能影響之分析』，國立台灣大學機械工程研究所碩士論文，中華民國九十五年。

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