Design of fully redundant autonomous life support systems.

Abstract

Certain military, exploration, and industrial environments require the use of portable, redundant life support systems to permit extended manned work in remote locations, free of safety umbilicals and lacking immediate recourse to a safe-haven. Such environments include extravehicular activity in space, deep off-shore diving work. submarine-based military diving missions, and the exploration of underwater caverns. Redundancy implies that several critical components in a life support system can fail and still leave the user with a functional system. The terms System Failure and Mission Failure are defined and a simplified procedure is presented by which complex life support systems can be analyzed to determine their degree of redundancy (survivability) both from the system failure and mission failure points of view. The significance of levels of redundancy and trade-offs in system complexity are discussed. Examples of practical implementations of redundant systems are presented.