High Energy Capacity Shock Absorber with Tunable External Bypass

Physical Sciences Inc., in collaboration with Enidine, proposes to develop an electronically adjustable external bypass shock absorber for oversized applications. The proposed 250-kip design has an 80” stroke and utilizes a sharp orifice pattern internal and external to the outer cylinder. Flow through the external orifice pattern can be remotely restricted via electronic valves. Valve settings are predetermined from calibration curves based on predicted mass, impact velocity, and desired rebound rate. The internal orifice scheme is designed to meet the maximum energy condition with all external plumbing closed. The external orifice holes are placed inside a series of manifolds set along the length of the shock. Each manifold can be electronically/manually controlled individually, allowing the user to tune the response over stroke length. During impact, the internal pressure and piston position are monitored and compared with predicted values. Additional provisions include a nitrogen volume linked to an external accumulator, with an air bladder to control the return force/velocity of the piston and support a resting mass. All critical components are designed with fatigue/service life of 500,000 cycles or 25 years. The shock design is compatible with wire rope or cable systems via multiple sheaves similar to aircraft carrier arrest gear.