Magnetorquers offer a method of controlling the attitude of a spacecraft either directly, by interacting with the local Earth’s magnetic field or, more usually, in combination with reaction wheels. This secondary method allows for the dumping of excess momentum in the reaction wheels without the need for a complex propulsion system.
The NewSpace Systems (NSS) magnetorquer rods use a magnetic alloy rod which produces an amplification effect over an air cored magnetorquer. This allows a system that uses less power and is less susceptible to magnetic torque variations due to temperature.
Each rod is typically bifilar wound for redundancy, or the windings can be activated together to increase the torque produced. While drive circuits for the rods can be supplied if required, they typically run directly between a switched power output and the on-board power control system.
The larger NSS magnetorquer rods were first flown in 2014 on the SaudiSat-4 and DX-1 missions. Since then, this product line has been delivered to a large number of international missions and constellations, all with differing performance requirements. To date, more than one hundred and fifty CubeSat rods have also been delivered.