Testing system for temperature gradients of large spacecraft structure under atmospheric pressure

Abstract

The invention discloses a testing system for temperature gradients of a large spacecraft structure under atmospheric pressure. The system comprises an atmospheric pressure temperature circulating device provided with a temperature gradient control system, a temperature measuring system, a mechanical property measuring system, a gravity unloading system and the like. The atmospheric pressure temperature circulating device is used for providing stable background temperature. The temperature gradient control system is used for locally heating a test specimen based on a PID algorithm to generate set temperature gradients. The temperature measuring system comprises a thermocouple and an infrared thermography non-contact temperature measuring system. The mechanical property measuring system comprises a strain gage and a non-contact deformation measurement system. A simulation system is capable of simulating temperature gradients of the large spacecraft structure on an orbit and measuring force and thermal properties corresponding to the structure on the environment of ground atmospheric pressure. The testing system for temperature gradients of the large spacecraft structure under atmospheric pressure has following beneficial effects: a new method is provided for simulation of temperature gradients of the ground; an atomospheric pressure device is used for checking the large spacecraft structure; safety and flexibly are high; test cost is reduced; and level and efficiency of a thermal test are improved.

Description

technical field [0001] The invention belongs to the field of spacecraft ground thermal tests, and in particular relates to a spacecraft ground normal pressure temperature gradient test system and a corresponding method. The temperature gradient simulation and corresponding thermal and mechanical characteristic tests of large-scale mechanisms are realized under the ground normal pressure environment. Background technique [0002] With the diversification of my country's aerospace missions and the development of aerospace models, more and more spacecraft are equipped with deployment trusses, large deployment antennas, robotic arms, etc. due to the requirements of spacecraft for earth observation and communication. Large-scale deployment mechanisms usually have a large number of moving parts or even stand-alone equipment. In order to verify their ability to work in extreme temperature environments and screen out early defects, atmospheric pressure thermal cycle equipment is usual...

AI Technical Summary

Problems solved by technology

[0003] In recent years, with the precision of the load on the large-scale mechanism of the spacecraft, it has also put forward strict requirements on the accuracy of the mechanism itself. Many foreign in-orbit abnormalities and faults show that when the large-scale mechanism as a whole is within the allowable temperature range, but There is a large temperature gradient on it, and when thermal deformation is caused, it may also have a great impact on the normal functions of the load on it, such as imaging and communication. How to ensure that the large mechanism is within the allowable working range, but when there is a large temperature gradient itself It is also one of the problems to be solved to verify the working status of

The United States "Constellation Project Environmental Appraisal and Acceptance Test Requirements" and other standards also mention that if the mechanical structure, solar battery wings, optical components, etc. are required, a thermal gradient test (Thermal Gradient Test) should be carried out, but the standard only mentions Using vacuum ring die equipment to carry out this type of test is difficult to apply to large-scale institutions over 10m in size, and there are problems such as high cost and complicated implementation.

[0004] The Chinese invention patent "CN201210270054.0 Atmospheric Pressure Thermal Test System and Method for Manned Spacecraft" has mentioned the simulation of heat flow outside the cabin of a manned spacecraft in a normal pressure environment to achieve the purpose of verifying and evaluating the thermal design of the cabin, but it only For spacecraft with sealed cabins, it is not suitable for mechanical measurements under extreme temperature gradients of large spacecraft mechanisms

At present, the corresponding test equipment used in the vacuum thermal test is difficult to adapt to the normal pressure thermal test environment, such as non-contact temperature measurement, deformation measurement system is difficult to withstand the high and low temperature of direct forced convection heat transfer; infrared lamp array, heating sheet, etc. Heating methods need to consider the large amount of heat taken away by forced convection, which may lead to problems such as insufficient heating capacity

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