The precise movements of a satellite in orbit is an orchestration of many variables, from gravity to positioning for solar power, communications and other factors. The precise movement of two satellites flying in formation in close proximity is another level of difficulty. It is a capability that the University of Toronto Institute for Aerospace Studies (UTIAS) Space Flight Laboratory (SFL) recently demonstrated and which at the NanoSat scale, is presumably a first.
The SFL is not only a Canadian leader in developing NanoSats, they are also recognized globally for their work with several nations contracting them to develop their NanoSats.
They’ve developed a Generic Nanosatellite Bus (GNB), basically the infrastructure of the satellite, for which components are then attached. The GNB and components of CanX-4 and CanX-5 weigh in at 6.5 kilograms and satellites measure 20x20cm in cube form.
The SFL has also developed a next generation Bus based on the GNB, the Nanosatellite for Earth Monitoring and Observation (NEMO) bus, which, as the name describes, will be used for Earth Observation.
This past June CanX-4 and CanX-5 were launched aboard an Indian rocket. Their primary mission was to demonstrate on-orbit formation flying. For this mission, that meant having the two satellites controlling their position and orientation with respect to one another.
According to the SFL, the CanX-4 and CanX-5 NanoSats in October “used their on-board propulsion, GPS-based relative navigation, and inter-satellite radios to execute a series of precise, controlled, autonomous formations, ranging from 1 km range down to 50 m separation. In each case, more than 10 orbits were accomplished with sub-meter formation control and centimeter-level relative navigation.”
The NanoSats are operated from the Microsatellite Science and Technology Center (MSTC) in Toronto where they were built and tested.
“CanX-4 and CanX-5 were designed to demonstrate formation flying in two along-track orbits, and two projected circular orbits,”, said Grant Bonin, the CanX-4&5 project manager. “We’re pleased to report that we’ve now completed all of the intended formations, and indications are that have out-performed our control performance requirements in every case. We are very pleased with the results.”
There are several applications these NanoSats can perform, ranging from on-orbit inspection and repair, sparse aperture sensing, interferometry, and ground moving target indication.
“CanX-4 and CanX-5 have pushed the boundary of what can be achieved with miniature spacecraft”, said Dr. Robert Zee, director of the Space Flight Laboratory. “These two satellites have allowed us to demonstrate high-performance formation flying algorithms and hardware that can enable a wide variety of small and large missions.”
The SFL intends on publishing their results over the next several months.
– Canadian Nanosats CanX-4 and CanX-5 Achieve Notable Firsts
– Two Nanosats Launched by India for the University of Toronto’s UTIAS Space Flight Lab