We design, fabricate and test a non-explosive separation actuator(NEA) that can replace the pyro-type device. Considering installation space, generative force, actuation time and shock level due to actuation, the proposed NEA employs a wire-type shape memory alloy(SMA). Through theoretical analysis and experiment, the specifications of the SMA wire to activate the separation device are determined. Then, an NEA with two wire-type SMAs is fabricated to activate two times. One is the primary actuator and the other one is redundant in case the primary actuator fails. In order to increase the reliability of the device, operation tests are performed more than 10 times. In addition, a release shock test under zero gravity condition was also carried, and this testrevealed very low shock compared to that of the pyro-type device. Conclusively, we developed an NEA that can operate reliably within 0.7 sec while generating less than 30G in the shock response spectrum(SRS).

This paper describes a newly designed ultimate load and release time controllable non-explosive separation device which is activated by a spring-type shape memory alloy (SMA) actuator. This device is comprised of a separation mechanism consisting of a deformation module, a blocker, the housing, two release springs and a spring-type SMA actuator. Through a theoretical approach, the ultimate load of the separation device and the required force to deform the deformation module according to the thickness of the deformation module are investigated. Based on theoretical results, the specifications of an SMA actuator to deform the deformation module are determined. In order to validate theoretical result, we manufactured a separation device which has a 1mm thickness of deformation module. Subsequently, the release time test, preload test, ultimate load test, and shock test are performed respectively. As a result, the release time with 30 W of power input is 55 sec. It actuates reliably under 150 N of preload and generates a maximum shock of -11.09 G when the diameter of the SMA wire is 1.75mm. The maximum ultimate-load for 1mm thickness of aluminum deformation module is 1,510N. Conclusively, satellite designers can select proper specification such as the ultimate load, shock level and release time according to satellite requirements by simply changing the thickness of the deformation module.

This paper describes development of a non-explosive separation device which can be equipped on small satellites. The spur geared micro DC motor, which has high reliability and advantage of price, is adopted as an actuator. The proposed separation device has resettability and it does not need extra jig to reload. In addition, the simple structure makes it easy to fabricate and assemble. To verify the performance of the proposed device, the response time tests, maximum preload tests and maximum shock level tests were performed. Also, through the vibration tests and thermal vacuum tests, feasibility of the proposed separation device was shown in launching and space environments. Therefore, we expect that the proposed separation device can replace the imported separation devices in near future.

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