Design And Achievement Of Quantitative Simulating Of Human Metabolic System

According to the "three steps" plan of China on astronautics, our country willbuild a large scale space station on which astronaut can live for a long time, whichrequires a new Environment Control and Life Support System（ECLSS）.In order tomake sure that the ECLSS can work long, stably and reliably, it needs to be test forseveral times on the ground before working formally. The human metabolicsimulation system is one of the confirmatory systems of ECLSS.Based on the situation of ECLSS of our country, combined with the supportingsystem of the International Space Station, a new human metabolic simulationsystem was invented which inculdes carbon dioxide（CO2） supply unit, humiditycompensating unit, heat compensating unit and oxygen（O2） consumption unit. Thispaper describes the overall and sub-unit design detaily.According to the accuracyrequirement, a suiable control system has been designed. And the appropriatehardware of the new human metabolic simulation system has been chosen.During the control system design, the PC software is LabVIEW which isused in test and measurement widely.And the interface of LabVIEW is also friendlyand easily to operate.The lower computer is PLC of the Siemens which is stable andreliable that is required of the design. Two modes of automatic and semi-automaticis designed of the system. The automatic system can simulate the each unit of thehuman metabolism quantitatively, consecutively and periodically. Thesemi-automatic mode can operate each unit independently and it also meets thedemand of the function of the level bias characteristic.The novelty of the design is that a new oxygen consumption unit has beeninvented according to the theory of "molecular sieve pressure swing adsorption".The benefits of using the theory is that it avoids the defect of traditional approachthat taking away CO₂and trace gases，which can reducing the environment of thecabin maximumly and test the ECLSS reliably.