A performance test method of a high damping micro-amplitude vibration isolator

Abstract

A high-damping micro-amplitude vibration isolator performance test method of the invention comprises the steps as follows: a vibration exciter applies an excitation load to a high-damping micro-amplitude vibration isolator through a loading rod; a force sensor I feeds the excitation load applied to the high-damping micro-amplitude vibration isolator back to a control system in real time; an acceleration sensor I and an acceleration sensor II measure the acceleration values at the two ends of the high-damping micro-amplitude vibration isolator in real time; a force sensor II measures a force value output by the high-damping micro-amplitude vibration isolator in real time; a data acquisition and analysis system collects and records the measurement data of the acceleration sensor I, the acceleration sensor II and the force sensor II in real time; the data acquisition and analysis system gets a hysteresis loop curve of the high-damping micro-amplitude vibration isolator at an excitation frequency, namely, a curve of a restoring force Fd- relative to a displacement x; and the control system makes a control driver regulate the load output by the vibration exciter in real time according to the excitation load fed back by the force sensor I and based on the curve of the restoring force Fd- relative to the displacement x so as to test the performance.

Description

technical field [0001] The invention belongs to the field of performance testing of aerospace devices, in particular to a performance testing method of a high-damping micro-amplitude vibration isolator. Background technique [0002] With the development of remote sensing satellite technology, the imaging accuracy of loads such as ground optical imaging cameras, ground surveying and mapping cameras, and surveying and mapping radars is getting higher and higher, and they are more sensitive to micro-vibration interference. In order to effectively suppress the interference of micro-vibrations and ensure imaging accuracy, these satellites generally use vibration isolators with the characteristics of large damping and micro-deformation (that is, micro-amplitude), such as "a micro-vibration isolation device with high load-bearing capacity and high damping The fretting vibration isolator invented by the [0003] Accurate performance parameter values ​​(ie, damping coefficient and s...

AI Technical Summary

Problems solved by technology

Commonly used testing methods include the half-power bandwidth method, free decay method, etc. The premise of these methods is that the damping is small, and the test error is relatively large for the vibration isolator with high damping

In addition, the testing equipment commonly used in engineering is fatigue testing machine, material testing machine, cam testing system, etc. These equipment are suitable for the measurement of conventional large deformation (that is, large amplitude) vibration isolators, and for high The test error of the damped micro-amplitude vibration isolator is often very large, and sometimes the test error can even obliterate the working deformation of the vibration isolator itself, so it is difficult to meet the use requirements

In addition, for the performance test data of the vibration isolator, the traditional processing method is to directly obtain the stiffness coefficient of the vibration isolator according to the displacement value corresponding to the maximum damping force, and numerically integrate the measured damping force and displacement data to obtain the area of ​​the hysteresis loop. Calculate the damping coefficient of the vibration isolator. This method requires the measured damping force-displacement value to be the whole circle data. Usually, a special program is required to group the test data into the whole circle and delete the non-full circle part, which will bring a large workload and cause data waste, and this method cannot obtain confidence limit estimates for damping coefficients and stiffness coefficients, and cannot carry out accurate vibration isolation design for spacecraft

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