Rascal-1: A Do-si-do in Space

2016-2017

About

A 6U mission to demonstrate key technologies for proximity operations and space situational awareness. Rascal has been selected by NASA to fly in 2018 as part of the ELaNa-21 mission.

Mission 

Rascal is a two-spacecraft mission designed by St. Louis University to demonstrate key technologies for proximity operations and space situational awareness: infrared imaging, 6DOF propulsion, RF proximity sensing, and automated operations. It consists of two 3U Cubesat spacecraft fastened to a common baseplate; the system launches as a single 6U.

2017 Update: Mission scrapped due to scope and budget creep

Engineering 

After the on-orbit checkout, one 3U spacecraft was released and passively drifted away; both spacecraft observed the other in visible, IR and RF bands, determining the maximum range for each detection method. After a suitable distance, the released spacecraft activated its propulsion system and returned to within a few meters of the base. The second spacecraft then released and the process was repeated until the end of the mission. 

Proximity operations is the ability to safely maneuver around of another, possibly non-cooperative, object - with ranges from hundreds of meters down to meters and even docking. Space situational awareness is the ability to determine the real-time space environment - both natural phenomena (solar wind, local electromagnetic activity, etc.) and artificial objects. Rascal demonstrated key technologies for these applications using simple, inexpensive spacecraft: 

· Spacecraft detection. Rascal characterized the effectiveness (i.e. range) of the following systems: 

o Infrared imaging 

o Visible imaging 

o Passive RF 

· Relative position. Rascal used the IR and visible cameras to determine range and relative orientation (pose) between the two spacecraft. 

· Proximity maneuvers. Rascal carried cold-gas 6DOF propulsion (3 translation, 3 rotation) to allow each spacecraft to “orbit” the other. The propulsion unit was 3D printed into a single unit, and used R134a as its propellant. 

· Automated operations. Rascal’s spacecraft was equipped with on-board software to automatically detect and maneuver, as well as automated fault handling.