Student Satellite Projects

The Ionospheric sCintillation Experimental CubeSat (ICE CUBE) is a two satellite mission designed to explore simple GPS scintillation experiments in the mid-equitorial region. The science instrument is the Cornell Cougar GPS receiver. The space based testbed consists of two clusters of 10cm CubeSats, to be flown in 2006. The satellite bus, a 10cm aluminum cube with functional power electronics, communication capability, and a science instrument. The attitude control system is based on a gravity gradient boom and magnetic coils.

The goal of Cornell ICECube satellite project in general is two-fold: First, to qualify the concept of small satellites as useful instruments for science and engineering, to lower the cost of space utilization and exploration; Second, to educate students in all major aspects of the design, construction, and launch of space satellite systems.

The ICECube mission will launch two 10cm cube satellites designed to study the effects of scintillations in the Earth’s ionosphere on communication signals. Irregularly structured ionospheric regions can cause diffraction and scattering of trans-ionospheric radio signals. When received at an antenna, these signals present random temporal fluctuations in both amplitude and phase. Ionospheric scintillations may cause problems such as signal power fading, phase cycle slips, receiver loss of lock, etc. They are also known to degrade the quality of satellite navigation systems. This degradation lowers the signal-to-noise ratio of received GPS signals. The satellite will include an on-board GPS receiver, which will record the SNR of the received signal from the GPS satellites. This information will be stored on the satellite until it is transmitted to the ground station where it will be used to characterize the effects of the scintillations on communication signals.

To date, the ICECube project has educated over 100 students in several disciplines (ME, AE, EE, CS), in several stages of education (High School, BS, MS, MEng, PhD).

The CubeSat program was established in 1999 by Stanford University, Cal Poly Tech, and One Stop Satellite Solutions in an effort to bring satellite development, launch, and operation more closely to the students. Said another way, most satellites take years to develop, usually wait to be launched, and usually must be operated by the government or NASA. This program is designed to make is very inexpensive ($30K+ satellite costs) to launch the satellites. In addition, launches occur on a yearly basis which allows universities to design and fly a new satellite each year.

Currently, the two Cornell ICECube satellites have been delivered to Cal Poly University for integration, with launch expected in January 2006.

The Ionospheric Observation Nanosatellite Formation (ION-F) comprises three 15 kg spacecraft designed and built in cooperation by Utah State University, University of Washington (Cornell University), and Virginia Polytechnic Institute in order to develop a space based distributed control testbed. A novel feature of the mission is the planned suite of formation flying control experiments involving the three satellites.

The ION-F mission is part of the Air Force Research Laboratory/AFOSR/DARPA University Nanosatellite Program, which provides technology development and demonstrations for the TechSat21 Program. The University Nanosatellite Program involves 10 universities building nanosatellites for a 2004 launch on a space shuttle mission. The ION-F satellites are being designed and built by students at the three universities, with close coordination to insure compatibility for launch, deployment, and the formation flying mission.

The ION-F satellites will have many of the capabilities necessary to demonstrate multiple spacecraft distributed control. These include propulsion, inter-satellite communication, and GPS measurements. Most of the technology development is being developed in parallel to the program. This includes the UW pulsed plasma thrusters (UW with Primex), and the inter-satellite crosslink/GPS system (Applied Physics Lab at Johns Hopkins under NASA funding).

The Dawgstar satellite, started in 1998-99, has educated over 75 students in several disciplines (ME, AE, EE, CS), in several stages of education (High School, BS, MS, MEng, PhD). The students designed the satellite in conjunction with other universities, presented to Air Force, NASA, and Industry, and worked with the NASA safety board to gain acceptances for Shuttle. Dawgstar is unique in its ability to integrate research (formation flying) and education (space systems engineering).

The PPT thrusters were designed as a part of the DAWGSTAR program to provide formation keeping, orbit maintenance and attitude control functions for satellites in the 10-100 kg range. Thrust is created when solid Teflon propellant is ionized by a pulsed, high current electrical arc and accelerated by a combination of electromagnetic and gas dynamic forces. The system presented provides thrust levels from 60 to 275 micro-N with specific impulses up to 625 sec. A centralized power-processing unit utilizing high voltage switching enables a reduction in system mass when compared to previous designs. The total mass for the system presented is 4.20 kg which enables control of three axes of rotation and two axes of translation. Approximately 1.7 Million pulses were successfully accumulated on the flight qualification unit representing a total system impulse of approximately 1000 N•s.

The Dawgstar satellite was completed through hardware development and testing. But, due to the Columbia shuttle accident and programmatic issues with the organization of the first nanosat program, the Dawgstar/ION-F mission currently does not have a flight scheduled. Many of the attributes have been re-incarnated into the CUSat mission (see below).

The CUSat will demonstrate how one spacecraft can diagnose the health and configuration of another, a capability that will help enable commercial, government, and manned space missions envisioned for the coming decades. The satellites will be designed, built, and operated primarily by Cornell students. One of the two spacecraft will capture three-dimensional imagery of the other with the help of carrier-phase differential GPS algorithms.

Cornell University Space Systems Labs is participating in the University Nanosatellite-4 program. This program is a joint venture between the Space Vehicles Directorate of the Air Force Research Laboratory, the Air Force Office of Scientific Research and the American Institute of Aeronautics and Astronautics. As participants, twelve universities design and fabricate proto-flight nanosatellites, each with a unique mission. The universities will participate in a June 2007 flight competition with the winner receiving accelerated flight upgrades and a fully sponsored launch.