Energy management of vehicle collision forces on automotive seats

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Includes bibliographical references (leaf 68).An energy management system (EMS) was designed to minimize front and rear collision forces experienced by the occupants of automotive vehicles by at least 50%. The EMS is a hydraulic damper consisting of a control valve, a pressure operated directional control valve, and a hydraulic cylinder. The system operates entirely upon the forces experienced in the collision and dissipates the energy through a 30° rotation of the occupant's seat back. The damper is designed to withstand the maximum collision forces resulting in front collisions at 30 mph and rear collision at 11 mph. The maximum chest load on an occupant in these collisions is approximately 5,000 lbs. A resulting maximum load of up to 13,900 lbs is exerted on the damper. The damper is designed to dissipate half of this energy and operate at an average load of 6,642 lbs and a corresponding pressure of 4,550 psi. The result of this damper is a 52% reduction in the force exerted on an occupant's chest in a front collision from 5000 lbs to 2390 lbs.by Jennifer Dawn Navarro.S.B