The Third-Generation Los Alamos 1.5U CubeSat Attitude Determination and Control System: Design and Initial On-Orbit Results

The 3rd Generation 1.5U CubeSat designed at Los Alamos National Laboratory (LANL) contains a compact 3-axis attitude determination and control system (ADCS) to support the pointing requirements of a deployable high-gain antenna. The hardware and software for the ADCS system were designed and built entirely at LANL with the goal of minimizing the size requirements and unit costs. The satellites employ a combination of magnetometers, sun-vector sensors, solid-state gyroscopes, and a star-field sensor for attitude determination. Attitude actuation is accomplished using either 3 magnetic torque rods or 4 momentum wheels arranged in a pyramid configuration. The on-board ADCS processor runs a real-time operating system that is fully reprogrammable while in orbit. The first two units were launched in November 2016 and both units are currently operating in orbit. We will present the design of the hardware and software systems, pre-launch testing and simulation, and initial on-orbit results