Natural Frequency Analysis of the Traffic Lights

交通號誌燈之自然頻率分析

10.6202/THJ.201912_(15).0005

張豐宜(Feng-I Chang)

traffic light ； natural frequency ； 交通號誌燈 ； 自然頻率

慈惠學報

15期（2019 / 12 / 01）

63 - 73

英文

In 1968, the United Nations standardized various road signs and signals: a red light means ＂stop＂ or ＂no turning left＂ and vehicles must stop behind the stop line at the intersection; a green light means ＂proceed＂ and vehicles can go straight and turn either left or right; an amber light means ＂a red light will appear soon＂ and no vehicle may cross the stop line, or a vehicle can enter the intersection if it is very close to the stop line and cannot stop safely. With the installation of traffic lights, traffic can be effectively controlled, which has evident effects on regulating traffic flow and reducing traffic accidents. Therefore, researchers began to study traffic lights; this study also aimed to simulate and analyze traffic lights. The process of this study can be divided into the following steps: Firstly, the management equation and boundary conditions of traffic lights are derived according to the principle of vibration mechanics; secondly, the natural frequency is derived by using the Engineering Mathematical Method to solve the management equation; lastly, the numerical results are analyzed and discussed. The data and analysis results obtained from the simulation of traffic lights in this study can be used as reference data for traffic light manufacturers in future designs and improvement.

1968年聯合國對各種信號燈作了規定，紅燈表示禁止通行或停止左轉彎，車輛必須在交叉路口停車線後停車。綠燈表示允許通行，車輛可以直行、左右轉彎。黃燈表示馬上要出現紅燈，車輛不能越過停止線，如果車輛已十分接近停止線而不能安全停車時，可以進入交叉路口。交通號誌燈的出現，使交通得以有效管制，對於疏導交通流量，減少交通事故有明顯效果。使得學者投入交通號誌燈的研究，而本文也針對交通號誌燈去做模擬及分析。研究過程可分成以下幾個步驟:第一、將交通號誌燈的管理方程式與邊界條件依振動力學原理推導出。第二、使用工程數學方法去求解管理方程式，可求出自然頻率。最後，分析數值結果與討論。本研究所模擬交通號誌燈，所得到的數據與分析結果可以做為日後交通號誌燈廠商設計與改良時之參考數據。

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