Application of rotational accelerometers on the measurement of automotive headlamp cut-off deviation

Automotive lighting products, such as Head Lamps (HL), Fog Lamps (FL), Daytime Running Lamps (DRL), face with mechanical vibrations during service life which may coincide with the resonance frequencies of the light source. When excited at resonance frequencies, especially in the case of HL’s, light beam cut-offline may deteriorate and vibration of light beam occurs. This situation is also called light flickering. This state has disturbing effect on the driver’s visibility, which is valid for both the driver and the counter drivers. Most of the automotive manufacturers have developed test specifications for evaluation of flickering state under sinusoidal frequency sweep acceleration loading and they have introduced limits for flickering angle range or displacement range of the light beam with respect to frequency measured on a screen which is put on a prescribed distance from the light source. In this study a traditional way of light beam flickering angle deviation measurement method of HL is presented. Furthermore, application of precise & efficient way of measurement method by the use of quartz rotational accelerometer is inspected.

Keywords:

Head Lamp, Light Beam Vibrations, Light Flickering, Quartz Rotational Accelerometer Sinusoidal Sweep Test, Resonance Search Test, Harmonic Sweep,

PDF

___

[1] Schuler, A.R., Grammatikos, A., Fegley, K. A., (1967). Measuring Rotational Motion with Linear Accelerometers. IEEE Transactions on Aerospace and Electronic Systems, 3: 465-472. doi: 10.1109/TAES.1967.5408811.
[2] Dumont, M., Kinsley, N., (2015). Rotational Accelerometers and Their Usage in Investigating Shaker Head Rotations. Sensors and Instrumentation. Conference Proceedings of the Society for Experimental Mechanics Series, 85-92. doi:10.1007/978-3-319-15212-7_10.
[3] Drozg, A., Rogelj, J., Čepon, G.,Boltežar, M., (2018). On the performance of direct piezoelectric rotational accelerometers in experimental structural dynamics. Measurement,127: 292-298. doi:10.1016/j.measurement. 2018.05.081.
[4] Tsai, S. H., Ouyang, H., Chang, J. Y., (2019). Identification of torsional receptances. Mechanical Systems and Signal Processing, 126:116-136. doi:10.1016/j.ymssp. 2019.01.050.
[5] Abramovitch, D. Y., (1997). Rejecting rotational disturbances on small disk drives using rotational accelerometers. Control Engineering Practice, 5(11): 1517-1524. doi:10.1016/S0967-0661(97)10005-3.
[6] Oboe, R., Vigna, B., Gola, A., (2000). Application of MEMS-based rotational accelerometers to vibration suppression in hard disk drives. 2000 Asia-Pacific Magnetic Recording Conference, Digests of APMRC2000 on Mechanical and Manufacturing Aspects of HDD,MP17/1-MP17/2. doi: 10.1109/APMRC.2000.898952.
[7] Roucoules, C., Chemin, F., Cros, C., (2010). FRF prediction and durability of optical module and headlamp. Proceedings of ISMA2010 including USD2010,1: 4373-4383.
[8] He, J. , Fu, Z.F, (2001). Modal Analysis. Butterworth – Heinemann, Linacre House, Jordan Hill, Oxford OX2 8DP 225 Wildwood Avenue, Woburn, MA 01801-2041.
[9] Meirovitch, L., (2001). Fundamentals of Vibrations. McGraw-Hill, Boston.

Yayın Aralığı: Yılda 4 Sayı
Başlangıç: 2017
Yayıncı: Ahmet Çalık

Arşiv