Aerospace Testing International
Aerospace Testing International, launched in July 2002, is published quarterly to a global fully registered audience of aerospace testing, evaluation and inspection professionals. Coverage embraces the very latest news, features, industry interviews and in-depth technology profiles on available/developing technology and solutions, plus specialist services for the aerospace testing community.
The ES series electro-dynamic vibration shakers manufactured by Dongling Technologies can simulate various dynamic environments and produce force ratings from 100N to 600kN. The 600kN electro-dynamic vibration shaker was released in 2015. The first 600kN electro-dynamic unit was configured with a large head expander and large slip table with high overturning moment capability.
The large 4.5×4.5 m slip table is capable of handling a maximum payload of 20,000kg and has a maximum overturning moment of 2000 N•m. As a result, the 600kN electro-dynamic vibration shaker has a wider operating frequency range from 2Hz~2000Hz compared with the alternatives of a multishaker or hydraulic shaker. This also satisfies the force and frequency response range needs of dynamic environmental tests. Moreover, the electro-dynamic vibration shaker removes the needs for synchronous operation of multiple shakers due to force limitations imposed by a single shaker.
The 600kN electro-dynamic vibration shaker has been widely applied in aerospace, as shown by the tests of a complete satellite, a lunar rover, space station components and large rockets. The size and performance of this vibration test system is remarkable because, for the first time, a fully assembled product test can be undertaken, while in the past only a component testing was available.
During testing, a fixture and test article often have different connection boundary conditions, which may result in unrealistic tests and further lead to a specimen’s inconsistent response in practical situations. Compared with the component-level testing, full assembly tests can easily solve these product failure problems that might not otherwise be encountered if only individual components were tested. Assembled test specimens can better simulate operating conditions of all components in unison, including the connections, contacts and friction between all parts. Also, all tested components will receive more practical stiffness and damping; avoid distortion caused by the fixture, remove the challenges of proper fixture design and mounting, and achieve a more natural response.
Large electro-dynamic vibration shakers can be applied to the dynamic environmental tests of all kinds of large-scale spacecraft assemblies. This type of shaker creates a more realistic simulation environment and achieves higher control accuracy. Additionally, the specimen installation process is closer to actual working conditions, which effectively avoid over-testing and can shorten cycle times. In this way, a product defect can be found in advance at the laboratory. Furthermore, it can provide more accurate and authentic data for design and manufacture, and help to improve the product reliability.