Reaction Wheels

Reaction wheels are a type of momentum exchange device used to control the attitude of a spacecraft. They work by spinning a flywheel in a controlled manner, which creates a gyroscopic effect that can be used to change the spacecraft's orientation. Reaction wheels are often used in conjunction with other attitude control devices, such as thrusters or magnetorquers.

How Reaction Wheels Work

Reaction wheels consist of a flywheel that is mounted on a gimbal system. The flywheel is spun up to a high speed, and the gimbal system is used to control the direction of the flywheel's spin axis. By changing the direction of the flywheel's spin axis, the spacecraft can create a torque that will change its attitude.

The amount of torque that a reaction wheel can create is proportional to the speed of the flywheel and the gimbal angle. The faster the flywheel spins, the more torque it can create. The larger the gimbal angle, the more the torque vector can be directed away from the flywheel's spin axis.

Advantages of Reaction Wheels