Project “Oasis”: Sample Return Mission To Comet Temple-1

Jet Propulsion Laboratories (JPL) has overseen exploration of the Solar System with robotic spacecraft during the past three and one half decades. We have all watched in amazement as Sojourner explored Ares Vallis or Galileo discovered intricate ice patterns on Jupiters moon Europa. Dr. Garrard thought it might be beneficial to our students if the design class would do a project which paralleled one of the many active JPL initiatives; he arranged an on-site visit for Prof Vano to explore the possibility. JPLs interest in our students and their willingness to share their experiences and perspective was outstanding. Prof Vano selected a sample/return mission to Comet Temple-1 as the 1998-99 spacecraft design project (see mission statement).

The Spacecraft Design Team was organized into six disciplines (see tabulation) at the beginning of Fall Quarter; two student Project Managers were chosen to lead the team and complete a conceptual design by the end of the quarter. The Transportation Systems discipline was responsible for the integration of the entire vehicle; Pro/ENGINEER was used as a tool to assemble the vehicle. The Lander/Return Systems discipline used comet models developed by JPL to design a method of anchoring the lander to the comet so that a core sample could be taken. The Structural Systems discipline was responsible for the primary structure of all vehicles. The Propulsion System discipline determined the most efficient trajectory between Earth launch and comet rendezvous; they selected an ion propulsion system following JPL’s successful Deep Space 4 demonstration. The Systems and Equipment discipline determined what kind of avionics the mission would require for control, navigation and communication, and then determined the power requirements for all the systems on-board the spacecraft. The Aeroshell discipline investigated aerobraking to recover the samples to low earth orbit. Each discipline presented their primary design issues to the entire team at regularly scheduled team meetings. The Project Managers organized and conducted the meetings and helped the team resolve conflicting issues. The team successfully presented their design at a formal Conceptual Design Review at the end of Fall Quarter.

Photographs of the Design teams and class simulated images are on the next page.

The design team was reorganized at the beginning of Winter Quarter to include special project groups which addressed the following open issues: solar-array deployment, lander attachment, core sampling, primary structure design and mission trajectory. Each group designed and fabricated a working model of their design and used it to test their design concepts. An additional group prepared a video to document the teams efforts. The result of the Spacecraft Design Teams year-long effort is summarized in the Pro/ENGINEER graphics presented herein. The vehicle is called "Oasis". The assembled vehicle is approximately 6 meters long (with landers, not including the 2 X 7 meter solar arrays), 2 meters in diameter and has a mass of 1335 kg (including landers and solar arrays).