Heat-activated Parachute Release System

Abstract

Release of a parachute at the apex of a rocket flight is a problem for every amateur rocket enthusiast. Existing commercially available methods all require the use of gunpowder, which can have licensing and safety complications depending upon the local laws. Axiomatic design analysis has shown that there is also high information content in this method. Users must precisely calculate the amount of black gunpowder to be used based upon altitude and rocket geometry. At the highest altitudes, gunpowder combustion gases are insufficient due to the low ambient pressure, so CO2 expansion actuation is used instead. These solutions using CO2 have lower information content, but are still activated using gunpowder and dependent upon altitude. Our analysis has led to the technique of using heat-activated materials as a CO2 valve release, a solution with lower information content. This design works with all sizes of amateur rockets up to Tripoli Rocketry Association Class 3 without knowledge of rocket apex altitude.