A Review of Air Suspension Systems for Improving Ride Comfort in Passenger Buses

Ma Thi Huyen Trang¹, Luong Chinh Long², Nguyen Khac Minh³, Nguyen Trong Hieu⁴

^{1, 2, 3, 4} Faculty of Vehicle and Energy Engineering, Thai Nguyen University of Technology, Thai Nguyen, Vietnam.    

Abstract

This paper reviews the role of air suspension systems in improving the ride comfort of passenger buses. The review brings together recent and representative studies on bus suspension dynamics, heavy-vehicle air suspension, air spring modelling, pneumatic vibration isolation, and intelligent suspension control. The literature shows that ride comfort is mainly governed by vehicle speed, load condition, road roughness, suspension configuration, air spring parameters, and the way the suspension is controlled. Compared with conventional leaf spring suspension, air suspension generally provides lower body acceleration, better load adaptability, and improved vibration isolation. Recent bus studies also show that full-vehicle modelling, GENSYS-based air spring models, genetic-algorithm optimisation, and active or semi-active control can further improve ride comfort while maintaining road-holding requirements. However, the reported improvement is not constant across all studies because it depends on the vehicle model, excitation profile, evaluation index, and validation method. This review indicates that future work should move from simplified simulation models toward experimentally validated full-bus models, including seat locations, passenger load distribution, road profile estimation, and chassis-seat-human vibration transmission. The paper provides a concise basis for selecting and developing air suspension systems for modern passenger buses.     

Keywords: Air suspension systems, Passenger bus, Ride comfort, RMS acceleration, Air spring, Vibration isolation, Intelligent control

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