NASA has selected 12 Next Space Technologies for Exploration Partnerships (NextSTEP) to advance concept studies and technology development projects in the areas of advanced propulsion, habitation and small satellites.
Selected advanced electric propulsion projects will develop propulsion technology systems in the 50- to 300-kilowatt range to meet the needs of a variety of deep space mission concepts. State-of-the-art electric propulsion technology currently employed by NASA generates less than five kilowatts, and systems being developed for the Asteroid Redirect Mission (ARM) Broad Area Announcement (BAA) are in the 40-kilowatt range.
The three NextSTEP advanced propulsion projects, $400,000 to $3.5 million per year per award, will have no more than a three-year performance period focused on ground testing efforts. NASA required a minimum of 50% cost sharing and/or matching for the proposed efforts, which may include prior industry investment.
The selected companies are:
* Ad Astra Rocket Company of Webster, Texas
* MSNW LLC of Redmond, Washington
* Aerojet Rocketdyne Inc. of Redmond, Washington
Ad Astra’s winning proposal for advancing the technology readiness of the VASIMR® engine was one of three selected in the field of advanced electric propulsion. Under this work, valued at approximately $10 million over three years, the partnership will advance the VASIMR® engine to a technology readiness level(TRL)greater than 5–a step closerto spaceflight –with a demonstration of the VX-200-SS
laboratory prototype, a fully integrated system capable of operating at high power continuously for a minimum of 100 hours
In 2013 , after more than $30 million in private capital , the company completed more than 10,000 successful high power firings of its most advanced VASIMR ® prototype , the VX – 200
, in Ad Astra’s Houston vacuum chamber facility. These tests demonstrated the engine’s excellent firing repeatability and performance (6 N thrust, 5000 sec sp and a thruster efficiency greater than 70%) with no measurable signs of engine wear.
New technological advances (for higher 100 hour endurance) will be fully integrated into a test article called the VX-200SS
(for steady state)
High Power Electric Propulsion (HiPEP) is a variation of ion thruster. It was ground-tested in 2003 by NASA and was intended for use on the Jupiter Icy Moons Orbiter, which was canceled in 2005.
The HiPEP thruster differs from earlier ion thrusters because the xenon ions are produced using a combination of microwave and magnetic fields. The ionization is achieved through a process called Electron Cyclotron Resonance (ECR). In ECR, the small number of free electrons present in the neutral gas gyrate around the static magnetic field lines. The injected microwaves’ frequency is set to match this gyrofrequency and a resonance is established
The thruster itself is in the 20-50 kW class, with a specific impulse of 6,000-9,000 seconds, and a propellant throughput capability exceeding 100 kg/kW. The goal of the project, as of June 2003, was to achieve a technology readiness level of 4-5 within 2 years.
The pre-prototype HiPEP produced 670 mN of thrust at a power level of 39.3 kW using 7.0 mg/s of fuel giving a specific impulse of 9620 s. Downrated to 24.4 kW, the HiPEP used 5.6 mg/s of fuel giving a specific impulse of 8270 s and 460 mN of thrust.
HiPEP test grid
Aerojet Ion drives
The EMPT thruster, funded by NASA, is a 1 kW-class RMF thruster, operates on the same physics principles as the ELF thruster. This device, less than 4 inches in diameter, has proven that pulsed inductive technolgoies can be succesfully miniaturized. Indeed, this thruster has demonstrated operation from 0.5 to 5 Joules, as well as the first pulsed inductive steady state operation. The EMPT has demonstrated greater than 1E8 continuous plasma discharges.
The EMPT (ElectroMagnetic Plasmoid Thruster) can get about 7000 ISP.
The Electromagneti Plasmoid Thruster (EMPT) is an electric propulsion thruster and power processing system that will allow a dramatic decrease in system mass and increase lifetime over traditional 500 – 5000 W propulsion systems. The EMPT employs a Rotating Magnetic Field (RMF) to produce large plasma currents inside a conical thruster creating a field – reversed (FRC) plasmoid that is magnetically isolated from the thruster walls. The intensified gradient magnetic field from the plasmoid, together with the large plasma currents, result in a large body force which expels the plasmoid at high velocity. The EMPT is a pulsed device, nominally operating at 1 kW with 1 Joule discharges. Presented is a theoretical introduction to the EMPT and current experimental results with operation from 500 – 5000 Watts . First, FRC formation and translation has been demonstrated at a scale not seen before, both in energy and in physical size. The EMPT has demonstrated that it is possible to build high – efficiency pulsed – inductive devices in the 1 J and 1 kW class of pulsed thruster. Finally, the EMPT has demonstrated multi-pulse and steady state operating of a pulsed – inductive – type thruster. Experimental results as well as thermal, engineering, and plasma design considerations for a steady operating pulsed thruster will be discussed . This paper seeks to provide an initial framework for considering the design and steady operation of pulsed, gaseous electromag netic thrusters. Gas utilization and input circuit energy efficiencies will be described.
SOURCES – NASA, Aerojet, Ad astra, MSNW LLC
Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.
Known for identifying cutting edge technologies, he is currently a Co-Founder of a startup and fundraiser for high potential early-stage companies. He is the Head of Research for Allocations for deep technology investments and an Angel Investor at Space Angels.
A frequent speaker at corporations, he has been a TEDx speaker, a Singularity University speaker and guest at numerous interviews for radio and podcasts. He is open to public speaking and advising engagements.