Technology Transfer

Mission Takes Control

NASA's "faster, better, cheaper" paradigm is not an objective of the New Millennium Program (NMP), but Deep Space 1 (DS1), NMP's first mission, has indicated the paradigm may be an underlying benefit from NMP. Since its October 1998 launch, DS1 nearly finished validating 12 new technologies, including artificial intelligence software known as Remote Agent. This mission is one of the first-ever deep space NASA launches to have technology, rather than science, as its key focus.

"Science mission project managers are reluctant to take the risk of using untested technologies," said Dr. Wesley Huntress, who was NASA's Associate Administrator for Space Science during the creation and development of DS1. "The New Millennium Program is devoted to testing out new technologies first so they can be used with greater confidence on upcoming faster, better, cheaper scientific missions of the early 21st century."

Tests also are being conducted on advanced technologies designed to make spacecraft smaller, less expensive and capable of more independent decision- making so that they rely less on tracking and intervention by ground controllers. DS1 has been guided most of the time by its autonomous navigation system. Additional testing remains for another of the autonomy technologies, and a final navigation system test is scheduled during an encounter with asteroid 1992 KD in late July.

The artificial intelligence experiment that primarily commanded DS1 for periods of time during three days in May is known as Remote Agent. The experiment's software was programmed to diagnose the cause of simulated problems, take corrective action and then monitor its performance. If there are last minute changes in the plan of the spacecraft, instead of having to scrap the whole program, the alterations are made on board.

On the first day, Remote Agent successfully controlled the spacecraft and its futuristic ion engine for nearly the entire day, while it resolved a simulated instrument failure. Then, the ground team detected an anomaly—the component that issues commands had suspended operation and Remote Agent did not command the spacecraft's ion propulsion system to shut down as expected. An easily correctable bug was identified, thus illustrating the value of testing on an operational spacecraft. A new experiment was designed to achieve the remaining objectives three days later.

This unique software was a collaborative development between Ames Research Center and the Jet Propulsion Laboratory (JPL). DS1, part of the New Millennium Program, is managed by JPL for the Office of Space Science at NASA Headquarters.

Decreasing Costs

Space missions can be time consuming and expensive. Remote Agent and DS1's other advanced technologies have the potential to contribute to decreased costs, thereby increasing the number of missions that can be conducted and the amount of knowledge that can be gained with a fixed budget.

Part of the high cost of space exploration is the cost of operating the Deep Space Network (DSN). If a mission is run by ground control, it must have frequent communication with Mission Control via the DSN. Remote Agent makes the spacecraft autonomous in that it can generate and execute its own plans, and then correct many failures without communicating with ground control. By cutting down on the amount of communication a spacecraft must have with Earth, the cost of the mission is decreased.

Equipment Sharing Saves Costs for DS1 and Mars Missions

An increasing trend in NASA's current era of "faster, better, cheaper" missions is for space missions to benefit and borrow from technologies flown on recent predecessors. DS1 has taken full advantage of this opportunity by purchasing spare hardware from Mars Pathfinder and other missions.

From antennas and headsets to computers and cables, there are many technology links between these missions. Although these are not advanced technologies in the way that DS1's 12 technologies are, this synergy between missions has helped boost reliability and save costs.

Some of the new technologies tested on DS1 are:

• Solar Electric Propulsion—This uses electricity and atoms to push the spacecraft through space. Ion engines accelerate over long times, giving each ion a tremendous burst of speed. The DS1 engine provides about 10 times the specific impulse (ratio of thrust to propellant used) of chemical propulsion.
  
  
• Solar Concentrator Arrays— solar arrays are less expensive and more resistant to radiation than conventional arrays.
  
  
• Autonomous Navigation—This allows DS1 to correct its course as it flies, using images of asteroids and stars collected by the onboard camera system, without needing help from ground control.
  
  
• Miniature Integrated Camera and Imaging Spectrometer—This combines several kinds of picture-taking devices into one low-mass system. The camera-imaging spectrometer package is about 10 times less in mass, cost and power consumption than conventional instruments that perform similar functions.

 

The first flight in NASA's New Millennium Program, Deep Space 1 is designed to validate 12 new technologies for scientific space missions of the next century.

• Miniature Integrated Ion and Electron Spectrometer—Several different measurement capabilities are integrated into one compact instrument that is one-quarter the size of currently used comparable instruments and requires less than half of the power of conventional instruments. This scientific instrument will help monitor possible incompatibilities of using the ion propulsion engine by measuring the energy spectrum of electrons and ions. It electrostatically sweeps its field of view with high-mass resolution, instead of using moving parts.
  
  
• Telecommunications Devices—New low-mass communications devices include a miniaturized 3.2-kilogram transponder and a high-frequency, solid-state amplifier that amplifies the transponder radio signal. Ka-band, the newest frequency being considered for deep space communications, is four times higher than the currently used X-band. A system with similar capability using current technology would be more than twice as heavy and cost three times as much.
  
  
• Beacon Monitor Operations—This technology sends one of four signals about spacecraft health to small receivers on Earth. Therefore, costly DSN time does not need to be used to get spacecraft health information, thus reducing the need for c onstant monitoring by mission controllers.
  
  
• Microelectronics and Spacecraft Structure—Sophisticated ultraminiaturized electronics that consume less power, and a multifunctional structure that integrates electronics with the spacecraft, demonstrate futuristic technologies for making the spacecraft smaller, lighter and more efficient.

More explanation of each technology is at http://nmp.jpl.nasa.gov/ds1/tech/advtech.html

For more information, contact David H. Lehman at Jet Propulsion Laboratory.
Call: 818/354-2023, Fax: 818/393-4277
E-mail: David.H.Lehman@jpl.nasa.gov
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