There are three main methods for CubeSats to stabilize: reaction wheels, magnetorquers, and permanent magnets. Reaction wheels would take too much space in our 1U CubeSat, while both reaction wheels and magnetorquers drain the invaluable solar power. That is why we decided to use a permanent magnet.
PMAC (Passive Magnetic Attitude Control):
PMAC consists of two main elements: a bar magnet and perpendicular hysteresis rods. The bar magnet stabilizes a CubeSat in two axes by lining itself up with Earth’s magnetic field. However, the CubeSat still spins on the third axis. That is why we use hysteresis rods to slow down the spinning. The time in which a CubeSat can stabilize depends on how strong is it tumbling after being deployed. For example, it could take two days to stabilize on the two axes controlled by the bar magnet, and it could take another eight days for the hysteresis rods to slow down the spinning.