Road Spectrum Analysis of High-Speed Rocket Sled Rail Based on Shock Response Spectrum

In order to evaluate the ride comfort of the high-speed rocket sled rail, an analysis method of dynamic road spectrum based on the rail's dynamic response is presented. In this method, the rocket sled test system is regarded as a sled-rail coupling system, the rail's dynamic response is used as the excitation conditions of the rocket sled, and the road spectrum is obtained through the shock response spectrum analysis. In the rocket sled test, when the rocket sled passes a given point of the rail, the acceleration of the point on the rail is selected as the excitation of the rocket sled, and the acceleration response spectrum is established by shock response spectrum transform. Then, the acceleration response spectrum is transformed to a displacement response spectrum. Finally, using the velocity of the rocket sled on the point, the displacement response spectrum is transformed to a spatial spectrum,i.e., the dynamic road spectrum. In addition, the dynamic road spectrum as high-speed rocket sled rail input is measured and analyzed. The results show that the rail characteristics based on the dynamic road spectrum analysis are consistent with the Holloman rail characteristics; the power spectral density is between 10-10-4 mm2m and the irregularity period is concentrated between 0.01-2.50 m-1.Therefore, the dynamic road spectrum can be used as the random excitation conditions of the high-speed rocket sled.