Recently, the team leads of our laboratory have decided to postpone the preliminary design review of the most recent project, Copper Rascal. The preliminary design review is a time for our design concepts to be critiqued by satellite development experts. We want the most relevant and meaningful critiques possible in order to ensure the best final satellite design. By postponing the preliminary design review, we are allowing teams more time to refine their plans for more time, a crucial step to furthering the development of our current plans.
A major aspect of the design that is still being debated is the attitude determination and control, or ADC. The ADC determines which approach we take to pointing the satellite in the proper direction. For this mission, that proper direction is downward facing. Currently, team leads are considering the use of permanent magnets, magnetorquers or gravity gradient booms for the ADC method. Fistly, the magnetic method is known as a "passive" system, because it doesn't consume any electricity and is a fairly common and easy-to-implement system. The two main drawbacks to this system are the facts that it only allows for two-axis control, and that due to the sun-synchronous orbit the magnetic field would turn the satellite at a relatively slow speed. Magnetorquers are very similar to the previous approach, except that instead of permanent magnets, we'd use a series of electromagnets that we could turn on or off, allowing for three-axis control, and avoid the flipping issue. One the other hand, this is an active system, meaning that we can control it from the ground but it consumes quite a substantial amount of electricity. Finally, gravity gradient booms are another passive method, except for the initial deployment, with reasonable calculations for precision. The disadvantage of this method is that it would be harder and expensive for us to build, due to its many vulnerable moving parts that are prone to breaking. The new preliminary design review date on is November 20th, and by then we are projected to have established our ADC as well as countless other aspects of the preliminary design.