NASA and Small Satellite Research

A presentation on NASA's interest in small satellites; nanosatellite missions, HQ Programs investments; future missions opportunities, and expanding NASA's technology portfolio

NASA Centers and Universities Collaborate in Annual Smallsat Technology Partnerships

The Small Spacecraft Technology program within the NASA Space Technology Mission Directorate sponsors the Smallsat Technology Partnerships (STP) initiative. The STP initiative awards cooperative agreements between NASA centers and university teams for technology development efforts that advance the capabilities of small spacecraft to achieve NASA mission objectives in unique and more affordable ways. NASA’s announcement to return humans to the Moon by 2024 raises new opportunities for Smallsats to contribute to missions in cislunar space, though technical challenges are to be overcome to establish their value in this environment. Precursor missions utilizing small spacecraft will blaze the trail for lunar exploration, establishing infrastructure such as communication and navigation networks, and performing assembly and repair services for larger structures and human habitats. To achieve these goals, certain novel Smallsat technologies will need to be developed and demonstrated. The 2020 STP solicitation sought proposals for specific technologies to enable these lunar missions. For the 2020 STP cycle, NASA selected nine university teams to mature new systems and capabilities in the laboratory, and in some cases, demonstrate in suborbital or orbital spaceflights. This paper describes the STP portfolio, past and present efforts, and the nine partnerships selected

Nanosatellite Launch Adapter System (NLAS)

The utility of small spacecraft based on the University cubesat standard is becoming evident as more and more agencies and organizations are launching or planning to include nanosatellites in their mission portfolios. Cubesats are typically launched as secondary spacecraft in enclosed, containerized deployers such as the CalPoly Poly Picosat Orbital Deployer (P-POD) system. The P-POD allows for ease of integration and significantly reduces the risk exposure to the primary spacecraft and mission. NASA/ARC and the Operationally Responsive Space office are collaborating to develop a Nanosatellite Launch Adapter System (NLAS), which can accommodate multiple cubesat or cubesat-derived spacecraft on a single launch vehicle. NLAS is composed of the adapter structure, P-POD or similar spacecraft dispensers, and a sequencer/deployer system. This paper describes the NLAS system and it s future capabilities, and also provides status on the system s development and potential first use in space

Inside NanoSail-D: A Tiny Satellite with Big Ideas

"Small But Mighty" certainly describes the NanoSail-D experiment and mission. Its unique goals and designs were simple, but the implications of this technology are far reaching. From a tiny 3U CubeSat, NanoSail-D deployed a 10 square meter solar sail. This was the first sail vehicle to orbit the earth and was only the second time a sail was unfurled in space. The NanoSail-D team included: two NASA centers, Marshall and Ames, the universities of Alabama in Huntsville and Santa Clara in California, the Air Force Research Laboratory and many contractors including NeXolve, Gray Research and several others. The collaborative nature was imperative to the success of this project. In addition, the Army Space and Missile Defense Command, the Von Braun Center for Science and Innovation and Dynetics Inc. jointly sponsored the NanoSail-D project. This paper presents in-depth insight into the NanoSail-D development. Its design was a combination of left over space hardware coupled with cutting edge technology. Since this NanoSail-D mission was different from the first, several modifications were necessary for the second NanoSail-D unit. Unforeseen problems arose during refurbishment of the second unit and the team had to overcome these obstacles. Simple interfaces, clear responsibilities and division of effort allowed the team members to work independently on the common goal. This endeavor formed working relationships lasting well beyond the end of this mission. NanoSail-D pushed the technology envelop with future applications for all classes of satellites. NanoSail-D is truly a small but mighty satellite, which may cast a very big shadow for years to come

Integration of a MicroCAT Propulsion System and a PhoneSat Bus into a 1.5U CubeSat

NASA Ames Research Center and the George Washington University have developed an electric propulsion subsystem that can be integrated into the PhoneSat bus. Experimental tests have shown a reliable performance by firing three different thrusters at various frequencies in vacuum conditions. The three thrusters were controlled by a SmartPhone that was running the PhoneSat software. The subsystem is fully operational and it requires low average power to function (about 0.1 W). The interface consists of a microcontroller that sends a trigger pulses to the PPU (Plasma Processing Unit), which is responsible for the thruster operation. Frequencies ranging from 1 to 50Hz have been tested, showing a strong flexibility. A SmartPhone acts as the main user interface for the selection of commands that control the entire system. The micro cathode arc thruster MicroCAT provides a high 1(sub sp) of 3000s that allows a 4kg satellite to obtain a (delta)V of 300m/s. The system mass is only 200g with a total of volume of 200(cu cm). The propellant is based on a solid cylinder made of Titanium, which is the cathode at the same time. This simplicity in the design avoids miniaturization and manufacturing problems. The characteristics of this thruster allow an array of MicroCATs to perform attitude control and orbital correcton maneuvers that will open the door for the implementation of an extensive collection of new mission concepts and space applications for CubeSats. NASA Ames is currently working on the integration of the system to fit the thrusters and PPU inside a 1.5U CubeSat together with the PhoneSat bus into a 1.5U CubeSat. This satellite is intended to be deployed from the ISS in 2015 and test the functionality of the thrusters by spinning the satellite around its long axis and measure the rotational speed with the phone byros. This test flight will raise the TRL of the propulsion system from 5 to 7 and will be a first test for further CubeSats with propulsion systems, a key subsystem for long duration or interplanetary CubeSat missions

Modular Pulsed Plasma Electric Propulsion System for Cubesats

Current capabilities of CubeSats must be improved in order to perform more ambitious missions. Electric propulsion systems will play a key role due to their large specific impulse. Compared to other propulsion alternatives, their simplicity allows an easier miniaturization and manufacturing of autonomous modules into the nano and pico-satellite platform. Pulsed Plasma Thrusters (PPTs) appear as one of the most promising technologies for the near term. The utilization of solid and non-volatile propellants, their low power requirements and their proven reliability in the large scale make them great candidates for rapid implementation. The main challenges are the integration and miniaturization of all the electronic circuitry into a printed circuit board (PCB) that can satisfy the strict requirements that CubeSats present. NASA Ames and the George Washington University have demonstrated functionality and control of three discrete Micro-Cathode Arc Thrusters (CAT) using a bench top configuration that was compatible with the ARC PhoneSat Bus. This demonstration was successfully conducted in a vaccum chamber at the ARC Environmental Test Laboratory. A new effort will integrate a low power Plasma Processing Unit and two plasma thrusters onto a single printed circuit board that will utilize less than 13 U of Bus volume. The target design will be optimized for the accommodation into the PhoneSatEDISON Demonstration of SmallSatellite Networks (EDSN) bus as it uses the same software interface application, which was demonstrated in the previous task. This paper describes the design, integration and architecture of the proposed propulsion subsystem for a planned Technology Demonstration Mission. In addition, a general review of the Pulsed Plasma technology available for CubeSats is presented in order to assess the necessary challenges to overcome further development

Nanosail-D: The Small Satellite That Could!

Three years from its initial design review, NanoSail-D successfully deployed its sail on January 20th, 2011. It became the first solar sail vehicle to orbit the earth and the second sail ever unfurled in space. The NanoSail-D mission had two main objectives: eject a nanosatellite from a microsatellite; deploy its sail from a highly compacted volume and low mass system to validate large structure deployment and potential de-orbit technologies. These objectives were successfully achieved and the de-orbit analysis is in process. This paper presents an overview of the NanoSail-D project and insights into how potential setbacks were overcome. Many lessons have been learned during these past three years and are discussed in light of the phenomenal success and interest that this small satellite has generated. NanoSail-D was jointly designed and built by NASA's Marshall Space Flight Center and NASA's Ames Research Center. ManTech/NeXolve Corporation also provided key sail design support. The NanoSail-D experiment is managed by Marshall and jointly sponsored by the Army Space and Missile Defense Command, the Von Braun Center for Science and Innovation and Dynetics Inc. Ground operations support was provided by Santa Clara University, with radio beacon packets received from amateur operators around the world

Micro Cathode Arc Thruster for PhoneSat: Development and Potential Applications

NASA Ames Research Center and the George Washington University are developing an electric propulsion subsystem that will be integrated into the PhoneSat bus. Experimental tests have shown a reliable performance by firing three different thrusters at various frequencies in vacuum conditions. The interface consists of a microcontroller that sends a trigger pulse to the Pulsed Plasma Unit that is responsible for the thruster operation. A Smartphone is utilized as the main user interface for the selection of commands that control the entire system. The propellant, which is the cathode itself, is a solid cylinder made of Titanium. This simplicity in the design avoids miniaturization and manufacturing problems. The characteristics of this thruster allow an array of CATs to perform attitude control and orbital correction maneuvers that will open the door for the implementation of an extensive collection of new mission concepts and space applications for CubeSats. NASA Ames is currently working on the integration of the system to fit the thrusters and the PPU inside a 1.5U CubeSat together with the PhoneSat bus. This satellite is intended to be deployed from the ISS in 2015 and test the functionality of the thrusters by spinning the satellite around its long axis and measure the rotational speed with the phone gyros. This test flight will raise the TRL of the propulsion system from 5 to 7 and will be a first test for further CubeSats with propulsion systems, a key subsystem for long duration or interplanetary small satellite missions

State of the Art: Small Spacecraft Technology

This report provides an overview of the current state-of-the-art of small spacecraft technology, with particular emphasis placed on the state-of-the-art of CubeSat-related technology. It was first commissioned by NASAs Small Spacecraft Technology Program (SSTP) in mid-2013 in response to the rapid growth in interest in using small spacecraft for many types of missions in Earth orbit and beyond, and was revised in mid-2015 and 2018. This work was funded by the Space Technology Mission Directorate (STMD). For the sake of this assessment, small spacecraft are defined to be spacecraft with a mass less than 180 kg. This report provides a summary of the state-of-the-art for each of the following small spacecraft technology domains: Complete Spacecraft, Power, Propulsion, Guidance Navigation and Control, Structures, Materials and Mechanisms, Thermal Control, Command and Data Handling, Communications, Integration, Launch and Deployment, Ground Data Systems and Operations, and Passive Deorbit Devices

BioSentinel: Monitoring DNA Damage Repair Beyond Low Earth Orbit on a 6U Nanosatellite

We are designing and developing a 6U nanosatellite as a secondary payload to fly aboard NASAs Space Launch System (SLS) Exploration Mission (EM) 1, scheduled for launch in late 2017. For the first time in over forty years, direct experimental data from biological studies beyond low Earth orbit (LEO) will be obtained during BioSentinels 12- to 18-month mission. BioSentinel will measure the damage and repair of DNA in a biological organism and allow us to compare that to information from onboard physical radiation sensors. This data will be available for validation of existing models and for extrapolation to humans.The BioSentinel experiment will use the organism Saccharomyces cerevisiae (yeast) to report DNA double-strand-break (DSB) events that result from space radiation. DSB repair exhibits striking conservation of repair proteins from yeast to humans. The flight strain will include engineered genetic defects that prevent growth and division until a radiation-induced DSB activates the yeasts DNA repair mechanisms. The triggered culture growth and metabolic activity directly indicate a DSB and its repair. The yeast will be carried in the dry state in independent microwells with support electronics. The measurement subsystem will sequentially activate and monitor wells, optically tracking cell growth and metabolism. BioSentinel will also include TimePix radiation sensors implemented by JSCs RadWorks group. Dose and Linear Energy Transfer (LET) data will be compared directly to the rate of DSB-and-repair events measured by the S. cerevisiae biosentinels. BioSentinel will mature nanosatellite technologies to include: deep space communications and navigation, autonomous attitude control and momentum management, and micropropulsion systems to provide an adaptable nanosatellite platform for deep space uses