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Feasibility evaluation of the replacement of pyrotechnically actuated valves, presently utilised in propulsion systems for their fast response and reliability, by valves actuated utilising Shape Memory Alloys properties

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Pyrovalves are presently used in space propulsion systems for their fast response, high reliability, low mass and low cost. However they are hazardous, single use items. Their operation induces shocks and can generate pollution. These drawbacks could be potentially eliminated by the use of shape memory actuators.

In this project a one use manually resettable SMA actuated valve has been developed. Two different models have been manufactured: a breadboard model to demonstrate the feasibility of the concept and then an engineering model with a more integrated design allowing vibration and leak testing.

The engineering model has shown very high reliability, in particular regarding cycling, vibration and leak tightness. In response to a number of spacecrafts failures in which pyrovalves are probably responsible, a first step in the direction of finding alternatives to these devices has then been accomplished. It opens new perspectives for spacecrafts propellant line design.