The Generic Nanosatellite Bus: From Space Astronomy to Formation Flying Demo to Responsive Space

Abstract

The Space Flight Laboratory (SFL) at the University of Toronto Institute for Aerospace Studies develops missions using spacecraft measuring 20 by 20 cm in its cross section and up to 40 cm in length. Each spacecraft can weigh up to 15 kg with up to 9 kg of payload. One of the three SFL operational missions uses the Generic Nanosatellite Bus (GNB) form factor and was conceived, built, and delivered into orbit within seven months from project inception. This nanosatellite precedes an operational 75 kg microsatellite mission by demonstrating the payload technology. Other technologies currently in orbit include reaction wheels and propulsion system, which will be used in follow up missions. Of the five nanosatellites currently under construction at SFL, two are intended for performing astrophysics investigation, two are intended for carrying out formation flying technology demonstration, and one is intended for performing preoperational duties as a way to fast track the readiness of new technologies that are slated for larger, operational missions; the latter is currently slated for launch in Q3 2009. In addition, SFL is also providing a number of critical subsystems for an operational microsatellite mission. These spacecraft build upon a set of common components and technologies that are shared across multiple missions and implement an architecture that is directly expandable to larger, operational missions. The development of these missions follows the microspace approach for managing risks and ensuring rapid development, which maintains cost-effectiveness and responsiveness to new missions. Typically each spacecraft implements multiple on-board computers, high data rate radios, sensors and actuators. The system implements a number of redundancies to mitigate failures. The subsystem complement and the complexity of the spacecraft can be tailored to meet various mission needs, from a passively stabilized spacecraft using permanent magnets to a three-axis stabilized platform with reaction wheels with optional propulsion system. The spacecraft can also accommodate fixed appendages such as booms, antennas, and additional solar panels. SFL also builds its own separation systems called “XPODs” and arranges, on a regular basis, shared launches for nanosatellite developers worldwide through its Nanosatellite Launch Service (NLS) program.