GAO Peng, SUNDa-gang, LIANGPei-gen, SHEN Yi

School of Mechanical Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, China

Noise and Vibration Control

Abstract :As a bionic buffer actuator, pneumatic artificial muscle （PAM） is used for a vibration isolation platform of a stretcher mounted in an ambulance. Damping model of the stretcher is built up, and the white noise is employed to simulate the pavement input. Simulation of the stretcher is conducted using simulation software Simulink and fuzzy PID control. The vertical acceleration and pitch angle acceleration are analyzed for the PAM stretcher and the traditional stretcher respectively in 3 working conditions. The simulation results show that the PAM stretcher can effectively reduce vibration impact to the stretcher and improve the comfort of patients. The research results may provide some references for the design of ambulance stretchers.

Key words :vibration and wave ;ambulance ;stretcher ;vibration isolation ;pneumatic artificial muscle

Ambulance stretcher vibration comfort is important for patients, especially patients who are critically ill. At present, many ambulance stretcher is directly connected with the body, it is necessary to stretcher "secondary isolation" in order to improve patient lying ride comfort. This article will be applied to the pneumatic artificial muscles ambulance stretcher buffer means build bionic buffer isolation platform, vibration isolation platform fixed directly connected with the compartment floor, on a stretcher after a car with a fixing device which can be quickly locked to the vibration isolation platform, in order to cushion vibrations transmitted to the patient.

Pneumatic artificial muscles (Pneumaticartificialmuscle referred PAM) is wrapped by a piece of external components header with bionics special fiber braid rubber sleeve and the ends of the composition, as biological muscle contraction that can produce a strong force, can be made into a new bionic pneumatic actuator. Its working principle is: the use of control methods to control the executive body of the PAM inflated, this time due to inflated PAM expands produce active axial tension, while almost no axial force generated when deflated, it is a one-way PAM active force actuator, so you can use it for active vibration control. Compared with other cushioning mechanism that has the following advantages: simple structure; the output power / weight ratio (shrinkage force cylinder with a diameter of 10 times); no adhesion, creeping phenomenon; variable stiffness, fast response, smooth operation; can be achieved by adjusting the pressure in the middle positioning. In this paper, PAM as an ambulance stretcher biomimetic actuators buffer isolation platform, preclude the use of fuzzy PID control method, the damping characteristics of the vehicle were studied stretcher.

This article attempts to apply to PAM stretcher ambulance vehicle vibration isolation platform to build a stretcher vibration mechanical model, using intelligent fuzzy PID control, the simulink simulation analysis shows that, PAM bionic stretcher isolation platform can effectively cushion road excitation vibration transmitted to the stretcher and patient and impact, Gao mention the ride lying supine patient comfort.

It indicates that the establishment of a stretcher - vehicle vibration system is reasonably practicable, verify the adaptive fuzzy PID control applied stretcher nonlinear control has some effect.

PAM as an active vibration isolation platform stretcher actuator, with its excellent dynamic characteristics and movements smooth, flexible, fast response, etc., can provide a reference for the ambulance stretcher design.