An integral part of the design of any artificial satellite or research spacecraft is the parabolic transceiver antenna used to transmit and receive radio signals from Earth. However, parabolic antennas acceptable in space are large and heavy and often difficult to fit under the hoods of launch vehicles. Researchers at Mitsubishi Electric Research Laboratories in Massachusetts, USA, have recently developed three-dimensional space printing technology that allows any spacecraft to print on it a space antenna of any size.

The antenna is printed with a special photosensitive polymer that cures very quickly under ultraviolet light emitted by the sun. This approach allows you to print an antenna with the required gain and bandwidth, while solving another serious problem. Devices launched from Earth are exposed to heavy loads and vibrations. Therefore, antennas, like other structural members, must be designed and manufactured to withstand the load on start-up, resulting in an even greater increase in weight, antenna cost and overall start-up cost.

MERL experts cited the Cassini spacecraft, launched in 1997, as an example. It has an antenna with a diameter of 4 meters and a weight of 105 kilograms. If this device could print an antenna in space, it would save 80 kilograms of precious weight.

An important component of the new space technology of 3D printing is a special composition of polymer material. “If you put ordinary polymer or resin in a vacuum chamber, it will start to boil, evaporate and contaminate everything around it,” the researchers write. Therefore, the researchers had to develop a special composition from a field-sensitive, light-sensitive polymer that could be vacuum extruded from the printhead and cured in a few seconds in the sun. In addition, the polymer can withstand temperatures of up to 400 degrees Celsius after curing. And most importantly, the production of space polymer is no more expensive than the production of conventional polymers.

The process of pressing the antenna is to extrude the polymer at a certain speed at the end of a rotating round base that cures rapidly in the light. And so, the ball is printed until the entire antenna reaches a certain diameter, and by moving the head during printing, the parabolic shape of the antenna is obtained. And finally, a metallization layer is applied to the surface of the antenna, which is a reflector for radio waves. This is done with another nozzle that vaporizes the aluminum and sprays it onto the surface. This process is used to metallize the film from which packaging such as chips and food packages are made.

MERL specialists have already printed a prototype of a parabolic antenna with a diameter of 165 millimeters in its laboratory in a vacuum chamber. Tests have shown that this antenna has a gain of 13.5 GHz, that is, 23.5 dB. Ku. in the standard communication range. The next step would be to weightlessly print the antenna in a vacuum chamber in low Earth orbit, and then print your own antenna CubeSat satellite that is in real space.

Advances in space 3D printing technology have enabled devices to include not only antennas, but also related design elements, all kinds of racks, stops, clamps, etc. This will reduce the weight of the cargo and the cost of launching into space. Source