TechEdSat-4 is the third generation in the TechEdSat-X series. The TechEdSat Series uses the CubeSat standards established by the California Polytechnic State University (Cal Poly), San Luis Obispo. With typical blocks being constructed from 1-unit (1U = 10x10x10 cm) increments, the TechEdSat-4 has a 3U volume with a 30 cm length. The project uniquely pairs advanced university students with NASA researchers in a rapid design-to-flight experience lasting 1-2 semesters. The TechEdSat Nano-Satellite Series provides a rapid platform for testing technologies for future NASA Earth and planetary missions, as well as providing students with an early exposure to flight hardware development and management.
TechEdSat-1 (a 1U), the first in the series, successfully demonstrated the use of an AAC (Angstrom Aerospace Corporation USA) Power Board to power the satellite, and the radiation-tolerant nanoRTU (nano-Remove Terminal Unit) to control a StenSat radio that provided basic housekeeping and space environmental data. It was part of the first group of CubeSats to be deployed from the International Space Station (ISS) on October 4, 2012 – and functioned 7 months until it re-entered Earth’s atmosphere.
The objective of the TechEdSat-4 mission is to demonstrate two new technologies including a system to provide satellite-to-satellite communications and information about the spacecraft’s health, as well as an upgraded exo-brake device to demonstrate a passive deorbiting system capable of accurately reentering Earth’s atmosphere. The exo-brake is an exo-atmospheric passive braking device, like a specially designed parachute that operates at extremely low pressures, which will eventually enable small samples to be returned from the space station or other orbital platforms. In addition, this technology is intended to help enable future small or nanosatellite missions to the surface of Mars and other planetary bodies in the solar system.
TechEdSat-4 will be the first NASA satellite to jettison into orbit from the Nanoracks CubeSat Deployer, and will develop further the exo-brake passive deorbiting system by adding drag-modulation for accurate de-orbit and eventual re-entry control. It is also demonstrating a satellite-to-satellite communications system that will allow for more frequent communication sessions with the satellite that lead to a higher accuracy of satellite altitude and position predictions which are important for the operation of the exo-brake.
The satellite’s structure, avionics, and payload, were custom designed by the TechEdSat-4 team to utilize the 3U volume most efficiently and provide ample space for the exo-brake. The CubeSat’s hardware was mostly off the shelf components available to anyone in order to make it easily reproducible for future flight variations.
TechEdSat-4 was launched as a secondary cargo payload on July 13, 2014 on the Cygnus CRS Orb-2 ISS resupply mission. The launch vehicle was Antares-120 of OSC and the launch site was MARS (Mid-Atlantic Regional Spaceport), Wallops Island, VA. The pressurized Cygnus spacecraft delivered 1,657 kg of cargo to ISS, including 300 kg of standard crew supplies, systems hardware and of science and research equipment. The overarching goals of the TechEdSat-X series are to a) develop the requisite technologies for on-demand sample return capability from the ISS, and b) perform re-entry test flights and hardware validation for future nano-satellite missions to the Martian surface. Based on nanosat technology, these missions are proposed for the 2016-2020 timeframe. This may open up tremendous education and research opportunities as an extension of the ‘TechEdSat-X’ series.