A two-degree-of-freedom ambulance stretcher suspension Part 1: System overview

Abstract

Ambulance suspensions often give a poor ride, which may result in deterioration in the condition of ill or injured patients. Suspension of the ambulance stretcher itself is a lower cost option than a purpose- built ambulance suspension and may offer superior isolation of the patient from road-induced disturbances. This paper describes the development of a pneumatic stretcher suspension offering both pitch and heave isolation. Design and theoretical considerations are outlined, and preliminary performance figures reported. Subsequent parts of this paper will explore the dynamics of the system with pneumatic damping and report on the performance of the prototype suspension for a range of patient masses, damping levels and floor vibration inputs.

Keywords

suspension ambulance stretcher pitch heave vibration isolation

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