Identifier

etd-042915-145659

Abstract

This study presents the overall design of a 3U CubeSat equipped with commercial-off-the shelf hardware, Teflon-fueled micro-Pulsed Plasma Thrusters (µPPT) and an attitude determination and control system. The µPPT is sized by the impulse bit and pulse frequency required for continuous compensation of expected maximum disturbance torques at altitudes between 400 and 1000 km, and to perform stabilization of up to 20 deg/s and slew maneuvers of up to 180 degrees. The study involves realistic power constraints anticipated on the 3U CubeSat. Attitude estimation is implemented using the q-method for static attitude determination of the quaternion using pairs of the spacecraft-sun and magnetic field vectors. The quaternion estimate and the gyroscope measurements are used with an extended Kalman filter to obtain the attitude estimates. Proportional and derivative control algorithms use the static attitude estimation in order to calculate the angular momentum required to compensate for the disturbance torques and to achieve specified stabilization and slewing maneuvers or combinations. Two control methods are developed: paired firing method, and separate control algorithm and thruster allocation methods which determines the optimal utilization of the available thrusters and introduces redundancy. Simulations results are presented for a 3U CubeSat under stabilization, pointing, and pointing and spinning scenarios.

Publisher

Worcester Polytechnic Institute

Degree Name

MS

Department

Mechanical Engineering

Project Type

Thesis

Date Accepted

2015-04-29

Accessibility

Unrestricted

Subjects

attitude control, CubeSat, pulsed plasma thrusters

Share

COinS