Evaluation of Road Roughness and Vehicle Speed Effects on Vibration Comfort of School Bus Driver Seats following the ISO 2631-1 Standard and Occupational Health and Safety Legislation

Abstract

Human perception in terms of vehicle comfort problems is a significant issue for automotive manufacturers and academic researchers as evident from scientific papers available in the literature. In this study, the maximum vehicle speed is predicted for comfortable driving of school bus drivers at certain working conditions. First, a full-vehicle school bus model, which consists of a seat, vehicle body, wheels and suspension systems, is developed to evaluate vehicle seat comfort in accordance with International Organization for Standardization (ISO) 2631-1 and Occupational Health and Safety (OHS) legislation. Second, collected experimentally power spectrum densities of road roughness are converted to amplitude form in order to be an input to the developed full-vehicle model. Third, the frequency weighting factor, which is determined by International Organization for Standardization 2631-1, is applied to the calculated RMS acceleration of the seat. Finally, frequency-weighted RMS accelerations of the seat for various conditions of road roughness and vehicle speeds are obtained, and it is used to evaluate the bus driver seat comfort in accordance with ISO 2631-1. In addition, RMS accelerations of the bus driver seat are used to evaluate vehicle seat comfort in accordance with OHS legislation. It is concluded that the effects of vehicle speed and road roughness on comfortable driving are observed and maximum vehicle speed for comfortable driving decreases as the power spectrum density of road roughness increases. According to the results, measures to be taken in accordance with the OHS legislation are suggested.

Keywords

• School bus driver
• Vehicle seat comfort
• Road roughness
• Seat vibrations
• Occupational health and safety

References

1. [1] M. Kolich and S. M. Taboun, “Ergonomics modelling and evaluation of automobile seat comfort,” Ergonomics, vol. 47, no. 8, pp. 841-863, 2004.
2. [2] A. Yavuz and A. Guney, “Optimization of Suspension Characteristics for Increasing Expected Daily Exposure Durations in Vehicles According to ISO 2631-1 Standard using Genetic Algorithms,” INTER-NOISE and NOISE-CON Congress and Conference Proceedings, vol. 259, pp. 6225–6234, 2019.
3. [3] N. Gülteki̇n, M. Mayda, and M. Ki̇li̇t, “Benzin ve Dizel Motorlarda Devir Sayısının Titreşime Olan Etkisinin İncelenmesi/Investigation of the Effect of Revolution of Diesel and Gasoline Engines on Their Vibration,” Bitlis Eren Üniversitesi Fen Bilimleri Dergisi, vol. 6, no. 2, pp. 39–43, 2017.
4. [4] S. E. Hacibektasoglu, B. Mertoglu, and H. Tozan, “Application of a novel hybrid f-SC risk analysis method in the paint industry,” Sustainability, vol. 13, no. 24, p. 13605, 2021.
5. [5] I. Morag and G. Luria, “A framework for performing workplace hazard and risk analysis: a participative ergonomics approach,” Ergonomics, vol. 56, no. 7, pp. 1086–1100, 2013.
6. [6] J. Wang, S. Han, and X. Li, “3D fuzzy ergonomic analysis for rapid workplace design and modification in construction,” Autom. Constr., vol. 123, no. 103521, p. 103521, 2021.
7. [7] P. K. Marhavilas, D. Koulouriotis, and V. Gemeni, “Risk analysis and assessment methodologies in the work sites: On a review, classification and comparative study of the scientific literature of the period 2000–2009,” J. Loss Prev. Process Ind., vol. 24, no. 5, pp. 477–523, 2011.
8. [8] Çalışanların Titreşimle İlgili Risklerden Korunmalarına Dair Yönetmelik, Official Gazette 28743. 2013.

9. [9] R. M. Lorente-Pedreille, F. Brocal, M. A. Saenz-Nuño, and M. A. Sebastián, “Analysis of metrological requirements in occupational health and safety regulations related to the emerging risk of exposure to vibrations,” Appl. Sci. (Basel), vol. 10, no. 21, p. 7765, 2020.
10. [10] M. Bovenzi, “Low back pain disorders and exposure to whole-body vibration in the workplace,” Semin. Perinatol., vol. 20, no. 1, pp. 38–53, 1996.
11. [11] M. Milosevic and K. M. V. McConville, “Evaluation of protective gloves and working techniques for reducing hand-arm vibration exposure in the workplace,” J. Occup. Health, vol. 54, no. 3, pp. 250–253, 2012.
12. [12] I. J. Tiemessen, C. T. J. Hulshof, and M. H. W. Frings-Dresen, “An overview of strategies to reduce whole-body vibration exposure on drivers: A systematic review,” Int. J. Ind. Ergon., vol. 37, no. 3, pp. 245–256, 2007.
13. [13] A. Guney, “Taşıtlarda Titreşim ve Gürültü,” Lecture Notes, İTÜ, İstanbul, pp. 3-10, 1992.
14. [14] T. D. Gillespie, “Heavy Truck Ride,” in SAE Technical Paper Series, 1985.
15. [15] P. Múčka, “Simulated road profiles according to ISO 8608 in vibration analysis”. Journal of Testing and Evaluation, vol. 46, no. 1, pp. 405-418, 2017.
16. [16] P. Múčka, “Relation Between Seated Person Vibrations and the International Roughness Index” Transportation Research Record, vol. 2677, no. 6, pp. 351-364, 2023.
17. [17] P. Múčka, “New Transverse Unevenness Indexes of the Road Profile” Journal of Transportation Engineering, Part B: Pavements, vol. 148, no. 3, pp. 04022046, 2022.
18. [18] P. Múčka, G. J. Stein, P. Tobolka, “Whole-body vibration and vertical road profile displacement power spectral density” Vehicle System Dynamics, vol. 58, no. 4, pp. 630-656, 2020.
19. [19] İ. Karen, N. Kaya, F. Öztürk, İ. Korkmaz, M. Yıldızhan, and A. Yurttaş, “A design tool to evaluate the vehicle ride comfort characteristics: modeling, physical testing, and analysis,” Int. J. Adv. Manuf. Technol., vol. 60, no. 5–8, pp. 755–763, 2012.
20. [20] D. Sekulic, V. Dedovic, “The Effect of Stiffness and Damping of the Suspension System Elements on the Optimızation of the Vibratıonal Behaviour of a Bus,” International Journal for Traffic and Transport Engineering, vol. 1, no. 4, pp. 231–244, 2011.
21. [21] H. Braun, T. Hellenbroich, “Messergebnisse von Straßenunebenheiten”, VDI- Berichte Nr. 877, Düsseldorf: VDI-Verlag, 47-80, 1991.
22. [22] Mechanical Vibration and Shock-Evaluation of Human Exposure to Whole Body Vibration Part 1: General Requirements, International Organization for Standardization. Switzerland, 1997.
23. [23] M. Mitschke, Dynamik der Kraftfahrzeuge. Berlin: Springer-Verlag, 1984.
24. [24] MathWorks, Inc., Student Edition of MATLAB Version 4: Student User Guide. London, England: Prentice-Hall, 1995.
25. [25] P. Múčka, “Road roughness limit values based on measured vehicle vibration” Journal of Infrastructure Systems, vol. 23, no. 2, pp. 04016029, 2017.
26. [26] Measurement and Evaluation of Human Exposure to Whole-Body Mechanical Vibration and Repeated Shock. British Standards Institution, BS 6841, 1987.
27. [27] Directive 2002/24/EC of the European Parliament and of the Council. Official Journal of the European Communities, 2002.
28. [28] T. Doğan, B. Erdem, Z. Duran, “Oturma Pozisyonunda Çalışanların Tüm Vücut Titreşimi Maruziyetlerinin Belirlenmesinde Kullanılan ISO2631-1, ISO2631-5, BS6841 ve Avrupa Birliği Direktifi (EU) 2002/44/EC’nin Karşılaştırılması” Ergonomi, vol. 3, no. 2, pp. 108-117, 2020.
29. [29] C.A. Lewis, P.W. Johnson, “Whole-body vibration exposure in metropolitan bus drivers” Occupational medicine, vol. 62, no. 7, pp. 519-524, 2012.
30. [30] R.P. Blood, J.D. Ploger, M.G. Yost, R.P. Ching, P.W. Johnson, “Whole body vibration exposures in metropolitan bus drivers: A comparison of three seats” Journal of Sound and Vibration, vol. 329, no. 1, pp. 109-120, 2010.
31. [31] O. Thamsuwan, R.P. Blood, R.P. Ching, L. Boyle, P.W. Johnson, “Whole body vibration exposures in bus drivers: A comparison between a high-floor coach and a low-floor city bus” International Journal of Industrial Ergonomics, vol. 43, no. 1, pp. 9-17, 2013.