Isro receives patent for protective garment for human spaceflight

In yet another step towards sending the first Indian into space, the Indian Space Research Organisation (Isro) has received a patent for its Liquid Cooling and Heating Garment (LCHG) made of biocompatible fabrics and components to provide a comfortable temperature and removal of sweat for astronauts, for use in space for protection from hot and cold environments.

LCHGs are used in space, military applications, fire fighting and also for personal cooling and heating purposes for protection from hot and cold environments of industrial areas or in extreme temperature and humidity conditions that may exist in work environments. These garments have a system for circulating temperature controlling fluid into and out of the garments, for instance, through tubes inside the garment.

Isro's invention is designed to permit long term use of the garment without any impact on the wearer in terms of skin irritation or infection and is low in cost of manufacture, according to the patent specification filed by the organisation with the Patent Office in February 2016.

The garment is provided with an outer layer made of polymeric fabric net and an inner layer of polymeric fabric tricoting, which comes in contact with the skin of the wearer. Both the layers are separated by several tubes configured to circulate a heat transfer fluid across the body through at least one inlet and at least one outlet connected to a valve for controlling the supply of the heat transfer fluid to and from the reservoir.

The ISRO said that the garment is a close fitting long garment, covering the torso and limbs from neck to toe as a single piece lightweight comfort inner wear over which the flight suit has to be worn.

The orgnaisation further claimed that a specimen of the garment was employed and was operated. "The surface temperature of the inner layer was monitored. The air temperature and velocity over the garments was also simulated. Heat transfer effectiveness of the system for coolant flow rate of 100 ml/minute was obtained. Effectiveness of the LCHG system for total heat dissipation was proven by the experiments," ISRO said. It also claimed a heat transfer fluid rate of 50-1000 ml per minute.

Isro has initiated the Rs 10,000 crore project  - Gaganyaan  - with a target to send a human to space by 2022 and has been preparing various components and conducting experiments to make the project a success. The organisation plans to send three astronauts to orbit the Earth at an altitude of 400 kilometers, for up to 7 days. The organisation in January said that it had identified four Indian Air Force pilots as astronauts for the mission and they would be trained to execute the project. It has also set up a Human Space Flight Centre in Bengaluru, for the execution of the project and will conduct two unmanned missions prior to the mission

In April, 2020, ISRO issued an announcement of opportunity (AO) for development of technologies for sustained Indian Human Space Programme and apace exploration, for developing technologies in radiation hazards characterisation and mitigation techniques, space food and related technologies, inflatable habitats technology, human robotic interfaces, thermal protection systems, environmental control and life support system, green propulsion, advanced materials, debris management and mitigation, in situ 3D manufacturing technologies for space, among others.