A short-stroke energy absorber can be used to reduce parachute snatch force and the onset rate of the opening shock. Such a device must operate with the desired opening shock forces and be nonelastic, light, small, in parallel with the risers, and not result in asymmetric suspension after parachute opening. Assessment of the dynamic characteristics of the energy absorber will be accomplished by means of a dynamic model of parachute opening to be developed during the project. A small friction device based on the capstan principle will be used in conjunction with a slip-clutch, for repeated use, or a stitch-ripping mechanism, for one-shot use, to provide the needed retarding force. Methods for preventing asymmetric suspension will be studied. The relative cost advantages and disadvantages of one-shot and multi-use devices will be compared, and the best design selected based on technical as well as the cost and operational factors.
