Development of a Wiper Dynamics Analysis System

• Main Authors: Yan, Tzu-Hsiung, 顏子雄
• Other Authors: Tseng, Chyuan-Yow
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/cheu46

碩士 === 國立屏東科技大學 === 車輛工程系所 === 106 === The noise and vibration of automotive windscreen wiper become more noticeable, because cars become increasingly quieter and more comfort. Wiper vibration and noise can be classified into three main categories namely, squeal noise, chattering, and reversal noise. In order to qualify a wiper both qualitatively and quantitatively, a dynamic test system and the associated method for analyzing wiper noise and vibration were established and studied in this thesis. The goal is to establish quantitative performance indexes for qualifying a wiper being testing. The study begin with the establishment of hardware and software for the dynamic test and analysis system. The system includes a wiper test platform, hardware and software for procedure control, and a PC with data acquisition and analysis software. Sensors include two accelerometers, a strain gauge, an angle position sensor, and a microphone. The control software is implemented on a DSP based microcontroller. With the completion of the system, a series of experiments were carried out on two designs of flat wipers with same size made by different company for comparisons. Two values of attack angles were used, namely -6o/+6o and 0o/-12o, under wet and dry windscreen conditions, respectively. The conclusions from this study are as follows. 1. The strain gage mounted on the wiper arm is useful to reveal the dynamic characteristics of the friction force between the wiper and windscreen. 2. The microphone mounted on a designed position of windscreen can clearly characterize the wiping noise under high level of background noise. 3. It is found that the noise signal, the accelerometer signals mounted on middle and end of the wiper, respectively, and the friction force signals are highly correlated with each other when an unwanted vibration and noise occur such as chattering, squeal, stick-slip, and stick-slap phenomena. This implies that these four signals can be used to identify the occurrence of the unwanted dynamics of the wiper, and furthermore, their values can be used to define the indexes that qualify a wiper.