Most of the satellites that are launched into space have antennas for communications. Elaborate folding antennas are necessary in order to fit them inside the payload of the launch vehicle. Once the satellite reaches its preferred orbit, the antenna must be unfolded and spread out in order to function. Problems with deploying the antenna can be fatal to a satellite.
Now a new technology can 3-D print an antenna in space with the help of sunlight. This system can eliminate the current complex antenna deployment process and reduce the cost of the satellite and the possible problems with antenna deployment. This new system was developed by Mitsubishi Electric Corporation (MEC). It employs a special type of resin that turns into a rigid solid material when it is exposed to ultraviolet radiation from the sun.
So far, MEC has only been able to demonstrate the technology in a special test chamber that simulates the conditions in space. They have printed an antenna dish about six inches in diameter that performs as well as conventional satellite antennas.
The sensitivity of an antenna is directly related to the size of the antenna. The larger the antenna, the better it is able to detect and transmit signals. However, size has always been a problem for satellite antennas because they have to fit inside the fairing that makes up the upper section of a rocket. The antenna also has to be very sturdy in order to survive the intense vibrations that occur during launch. This increases the weight of the satellite. The heavier a satellite is, the more expensive it is to launch into orbit.
Components that are 3-D printed in space can be much lighter and thinner because they do not have to survive the rigors of launch. By 3-D printing antennas in space, the launchers would not only save money but, because their satellites would be lighter, they would also be able to launch much smaller satellites with much larger antennas that they could launch by current systems.
This technology prepares the way for “3D printing of very large structures in space,” which could never be launched by today’s systems.
The special photosensitive resin is also heat resistance. It can survive temperatures of up to seven hundred and fifty degrees Fahrenheit. This much higher than temperatures typically encountered by spacecraft in Earth orbit. The company said, in a statement, that “Spacecraft antenna designs are challenging due to their conflicting requirements for high gain, wide bandwidth and low weight. High gain and wide bandwidth necessarily require a large aperture, but economical orbital deployment conventionally dictates that designs be lightweight and small enough to fit or fold inside a launch vehicle or satellite deployment mechanism.”
The company also said that its resin is the first such compound that is suitable for use in a vacuum. It does not require atmospheric oxygen to prevent it from solidifying too quickly. The use of natural ultraviolet light to cure the resin reduces the power consumption of the 3-D printer.