US space agency NASA will be testing a roll-up solar panel on its International Space Station (ISS) which is flexible and when rolled-up becomes a compact cylinder. Called Roll-Out Solar Array, or ROSA, the new solar panel may result in cost cutting and can even provide increase in power for satellites in the future.
Traditional solar panels that power satellites can be heavy as in that case heavy panels are folded together using mechanical hinges. The ROSA is lighter and smaller than traditional solar panels. They have a centre wing made using a flexible material that contains photovoltaic cells to convert light into electricity.
A narrow arm on either side of the wing extends the length of the wing to provide support known as a high strain composite boom.
These high strain composite booms are like split tubes made out of a stiff composite material, flattened and rolled up lengthwise for launch.
Using stored energy from the structure of the booms, the array rolls or snaps open without a motor. It is released as each boom transitions from a coil shape to a straight support arm.
ROSA can provide power for a variety of future spacecraft as it can easily be adapted to different sizes including very large arrays. It can even manage to make solar arrays more compact and lighter weight for satellite radio and television, weather forecasting, GPS and other services used on Earth. The technology could also provide solar power in remote locations.
The technology for booms can also be applied for communications and radar antennas and other instruments. The ROSA investigation looks at how well this new type of solar panels deploys in the microgravity and extreme temperatures of space.
The investigation also measures the array’s strength and durability and how the structure responds to spacecraft manoeuvres.
“When the array is attached to a satellite, that spacecraft will need to manoeuvre, which creates torque and causes the wing, or blanket, to vibrate,” said Jeremy Banik, from the Kirtland Air Force Base in New Mexico.
“We need to know precisely when and how it vibrates so as not to lose control of the spacecraft. The only way to test that is in space,” said Banik.
“This structure is very thin, only a few millimetres thick, and heats up very quickly, dozens of degrees in a few seconds,” he said.
“That creates loads in the wing that could cause it to shudder. That would create problems, for example, if a satellite was trying to take a picture at the same time,” he added.