Control of the thermoregulation system (CTS) in a spacesuit using sensors on a person and in an autonomous life support system (ALS)

8th International Conference "Aviation and Cosmonautics-2009". Abstracts. p.105.

2nd All-Russian Conference of Scientists, Young Professionals and Students "Information Technologies in Aviation and Space Engineering-2009". Abstracts.

It is known that when working in space in a spacesuit, a person releases a lot of energy, about 1 kW (80% of which is spent on overcoming the resistance of the shell). This work turns into warmth inside the suit and is an unfavorable factor. Today there are two methods of heat removal - a water cooling suit (KVO) and gas ventilation. Each system uses two brushless centrifugal pumps. The heat exchanger in the system with water (KVO) operates according to a bypass scheme and is mechanically controlled by a knob on the operator's panel. In case of uncomfortable sensations, a person in space regulates heat output by himself. Such a system is used by all ASOZs of cosmonauts, astronauts and taikonauts.

The purpose of this work is to propose an alternative control system for pumps pumping water, which will be used as the main one for regular extravehicular activities and in case of failure, its old system will start working. The use of the new system allows a person not to be distracted from work and always feel comfortable, thereby increasing his labor productivity and the power supply unit can work longer than what is used today.

The paper describes a schematic diagram of this system, which consists of two sensors. The first sensor measures the thermal conductivity of the skin by irregular heating, the second - the temperature in the suit. One of the possible electrical circuits is given and elements for its implementation are selected. The method of calibrating the system for a specific person is described and data on which the conditions of comfort are determined are given. Electrical safety is ensured by low currents. Comparison of energy consumption with and without this modification is given for the average of all values. The technique of superposition and measurement of the first sensor is described. The application of this system is possible, since it takes up little space and is quite easily integrated into the LSI. Drawings are made in OrCAD and Compass (3D) systems, which can be easily modified and made calculations and measurements. For a better understanding of the issue of thermoregulation of human skin, a mathematical model is given and described.