Improvement of ride quality for patient lying in ambulance with a new hydro-pneumatic suspension

Bohuan Tan,Yuanchang Chen,Bangji Zhang,Yang Wu,Nong Zhang

doi:10.1177/1687814019837804

Abstract

Instability caused by emergency braking and steering during ambulance operation would easily lead to a sharp rise of blood pressure in patient’s head, which would further cause a secondary injury t...

Highlights

Ambulances are important in transporting injured patients as well as providing first aid to patients
The equivalent relative deformations of four cylinders are expressed as SK x, and the equivalent velocity flowing through accumulator damper valve (ADV), piston head damper valve (PHDV), and piston rod damper valve (PRDV) is respectively defined as SK x_, SH x_, and SRx_
In order to estimate the dynamic performance, the power spectral density (PSD) responses to random excitation inputs are taken into consideration

Summary

Introduction

Ambulances are important in transporting injured patients as well as providing first aid to patients. Motivated by the aforementioned discussion, this study presents a PR-IHPS system to improve stability and attenuate vibration for both lying patients and paramedics This new suspension system can achieve enhanced cooperative control of the bounce and pitch/ roll motion-modes for the ambulance. In section ‘‘Ambulance model with PR-IHPS,’’ the ambulance with pitch-roll-interconnected hydro-pneumatic suspension (APR-IHPS) model is developed Based on this model, the additional characteristics by APR-IHPS are discussed as shown in section ‘‘Characteristic analysis of PR-IHPS system.’’ In section ‘‘MESD method,’’ the MESD method for obtaining the vibration energy of each motion-mode in frequency domain is proposed, and the equations of solving MESD of APRIHPS are derived. The relationship can be applied to four-cylinder chambers

ÀSflT aSflT Àtf SflT SflT 0

Design approach

Results and discussions

Conclusion