登山自行車後避震系統動力學分析

Off-road bicycle rear suspension dynamic analysis

黃澤平(Tse-Peng Huang)

指導教授 ： 楊大中

元智大學/工程學院/機械工程學系/碩士(2013年)

https://doi.org/10.6838/YZU.2013.00330

摘要

本文以Solidworks建構市售型浮動轉點全避震車架、兩種路面模型，搭配模擬軟體ADAMS View建立力學模型。調整市售型車架後避震連桿與主車架轉點位置，產生9種模型。以峰值車架垂直加速度與加速度之RMS值，分析舒適性能。探討力比與舒適性能關係，歸納出力比越大整體舒適性能越佳之結論。
模擬結果顯示九個車架最大垂直加速度均低於8 ，力比最大之模型，加速度RMS值最小，峰值加速度最大；力比最小之模型，加速度RMS值最大，峰值加速度最小。歸納出避震連桿力比與舒適性的調整策略，必須在峰值與整體性能之間做取捨。
提高後避震力比對峰值震動的影響微乎其微，對後續震盪抑制有明顯的效果。

關鍵字

登山自行車 ； 後避震 ； 浮動轉點 ； 力比

並列摘要

The relationship between fore ratio of rear suspension and mountain bicycle riding comfort is a major concern of this study. In this paper, a commercial floating pivot type full-suspension bicycle model and two road models were constructed by CAD software package, Solidworks.
First, the dynamics model was built by CAE software package, ADAMS. Using the commercial full-suspension bicycle as a prototype of the upper link of bicycle frame, build a 9 upper link with different geometry. Next, Compare force ratio, peak accelerations and the acceleration signals RMS values of 9 models.
As indicated by the simulation results, the maximal peak acceleration of 9 models all below 8m⁄s^2 , smaller than the single pivot full-suspension simulation results from Lin's[13] and Lee's[14] studies. The model with the biggest force ratio has the smallest RMS value of acceleration but minimal peak acceleration. The model with the smallest force ratio has the biggest RMS value of acceleration but maximal peak acceleration.
Accordingly, there is a contradiction between peak acceleration and RMS value of acceleration, also the overall acceleration performance. Reducing the force ratio of the rear suspension mechanism could reduce the average vertical acceleration of the rider’s seat of the bicycle and offer better ridding comfort, but could also induce uncomfortable vertical acceleration of the rider’s seat slightly.

並列關鍵字

Mountain bicycle ； Rear suspension ； Floating pivot ； Force ratio

參考文獻

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