Volume 5, Number 5 September/October 1997
HE MARS PATHFINDER IS ONE OF THE FIRST missions in a new, decade-long NASA program of robotic exploration. The purpose of the program is to expand scientists' knowledge of Mars while showing a number of technologies with promising commercial applications, including a partnership with Mattel Inc. The Mars Pathfinder has renewed public interest in the space program.
Some of the more interesting emerging technologies from the Mars Pathfinder and the future Mars '98 mission are the rocker-bogie suspension, silica aerogel insulation, DARTS (Dynamics Algorithms for Real-Time Simulation) software, the piezoelectric ultrasonic motor, the surface acoustic wave microhygrometer and a newly developed, lightweight carbon-fiber composite. Each of these technologies is in a different stage of development toward becoming licensablemeaning some have not been patented, some are in the process of being patented, and others are far from being patented (requiring technologies to be patented before they can be licensed). One particular commercial spinoff that has been tested by tens of thousands of children (and adults), the Sojourner rover toy, has provided education and restored public excitement about the space program.
Toy Version of Sojourner
The Mattel Hot Wheels JPL Sojourner Mars Rover Action Pack set, a toy version of Sojourner, not only aroused interest in the space program but in other technologies as well. A novel partnership between Mattel Inc. and JPL created both a burst of licensing activity and a unique opportunity for JPL's Commercial Technology program to link with the private sector and entrepreneurs. This partnership also attracted media attention, providing a platform to focus on the direct benefits to the public from technology developed for space missions.
"We've signed 37 new licenses related to Pathfinder," states Dr. James Rooney, manager of JPL's Technology Affiliates program, including quick-turnaround consumer items such as T-shirts and hats.
The partnership evolved into a three-part toy of Sojourner, the Pathfinder spacecraft and a lander. Many of the Pathfinder rover's unique attributes are included, such as the rocker-bogie's six-wheel suspension, which has other, more meaningful commercial application possibilities.
|It rocks, it rolls, it boogiesthe Mattel Hot Wheels toy. JPL licensed the Sojourner rover to Mattel Inc., which manufactured the highly successful Hot Wheels JPL Sojourner Mars Rover Action Pack set, recreating such details as the rover's unusual "rocker-bogie" locomotion system. (Sojourner , Mars Rover and Spacecraft Design and Images are copyright © 199697, Jet Propulsion Laboratory, California Institute of Technology. All rights reserved. Further reproduction prohibited.)|
The unique rocker-bogie suspension that gives Sojourner its peculiar, insect-like look offers great stability and an enhanced ability to negotiate large rocks nearly as high as the rover itself. The JPL-patented suspension joins the three wheels on each side with only two swinging joints, and it connects the whole three-wheeled bogie to the chassis at a single point. The structure has no springs, and the freely rotating joints flex to conform to ground contours and climb obstacles. The rover combines independent drive and individual steering (Ackerman steering) for each wheel.
Perhaps the most entertaining commercialization for the stable and agile suspension system was the Mattel toy. The more practical and useful applications for rocker-bogie technology include off-road, all-terrain vehicles for recreation, research and forestry; military scout vehicles; highly mobile handicapped assistance vehicles; search and rescue vehicles; and emergency robots for fighting fires, handling hazardous materials and defusing bombs. JPL is currently developing the suspension for improved mobility to enable robots to clear standard stair steps and travel over dry sand.
Silica Aerogel Insulation
One of the world's best insulations because of its remarkable properties, silica aerogel, is critical in keeping the Pathfinder's vital electronics at proper operating temperature. It shows great promise in numerous commercial venues, such as refrigerators, delivery boxes for cold or hot food, thermos bottles, ice chests and cold-weather protection in extreme climates. Silica aerogel is the electronics insulation material in the Pathfinder rover's warm equipment box when surface temperatures at Ares Vallis plunged to approximately 100 degrees Fahrenheit every night, making proper operating temperatures critical to the mission.
JPL is exploring ways to commercialize silica aerogel because of its structural and insulating properties. Even though aerogel is processed from silica and is chemically identical to glass, its frothy molecular structure gives it a specific density only a few times that of air. Properly supported, aerogel can bear up to a thousand times its own weight. JPL is currently using aerogel in the Stardust spacecraft to catch high-velocity cometary and interstellar dust particles without contact vaporization.
DARTS (Dynamics Algorithms for Real-Time Simulation)
One of the new software packages used on the Mars Pathfinder, DARTS (Dynamics Algorithms for Real-Time Simulation), just won NASA's 1997 Software of the Year Award (SYA). The software has saved NASA millions of dollars. Although it is too new to realize its commercial applications, NASA officials give praise and promise for its applications in space and other research fields.
Written by the JPL team of Abhinandan Jain, Guillermo Rodriguez and Guy K. Man, DARTS generates real-time simulations to test and verify flight software and hardware for a variety of spacecraft missions. The spatial operator algebra, developed in 1991 and a 1994 SYA winner, has improved fidelity and speed processing 10 million times faster than prior versions of such software.
The software is being called "cutting edge" by NASA officials and other industry professionals, explaining why potential commercial applications have not yet been explored. Its potential is every three-dimensional animation program in existence or to be developed, officials say, because it will model the program better than any other software. It has saved NASA more than $10 million to dateon the Galileo, Cassini, Stardust, New Millennium and Neptune Orbiter missions.
The Mars Pathfinder has emerged as
the quintessential model for NASA's
faster, better, cheaper paradigm.
The pharmacy research field has begun to use DARTS in pharmacokinetics, which studies the chemical and biological effects and reactions of drugs within the body, as well as in studying the cell level and DNA. In the molecular dynamics field, it is being adapted at Caltech to develop software, called NEIMO, for simulation and analysis of large-scale molecular systems in protein folding, drug design, catalysts, virus mechanisms and other applications of how molecules move through space.
Some possible commercial applications are in what professionals dub "the movement industry"transportation, automobile design and helicopters. The software could theoretically be applied to the entertainment industry, but officials say that is unlikely because the three-dimensional artistic approach is used in that area.
Piezoelectric Ultrasonic Motor
The ultrasonic solid-state motor planned for the robotic arm actuator on future Mars missions uses piezoelectric crystals instead of electromagnets, allowing it to work at temperatures near 240 degrees Fahrenheit, while featuring high reliability and low-power requirements. Its potential consumer uses include computer disc drives, automobile windshields, power windows and wipers, and actuators for microsurgical manipulators.
A microhygrometer, intended for possible use on the Mars '98 lander, was developed at JPL to measure humidity above the surface and in the soil. The size of a quarter, it combines a surface acoustic-wave device cooled with a tiny, two-stage thermoelectric cooler monitored with a co-mounted temperature sensor. Dramatically smaller than current hygrometers, this low-mass, low-power device responds more accurately and faster than conventional, state-of-the-art chilled-mirror hygrometers.
The combination of accuracy, sensitivity, low mass and volume, low-power requirements and rapid response makes for easier delivery and wider broadcast than ever before. The microhygrometer can track sudden changes in weather by measuring rapid humidity changes, and it can map atmospheric gradients from moving probes. This makes possible missions that were once thought inconceivable, such as more economical weather networks or three-dimensional atmospheric profiles.
Lightweight Carbon Composite
The robotic arm on the Mars '98 lander depends on the strong, machinable, three-dimensional carbon composite used in all critical load-bearing assemblies. Owing much to novel fabrication techniques developed at JPL, the composite weighs half as much as aluminum or the carbon composite materials now in current use, enabling lighter spacecraft and potentially lighter consumer products to be developed.
The new carbon composite is fabricated from very thin, very flat sheets that yield superior strength and stiffness compared to conventional, fabric-based composites. This innovative material sustains high friction with low wear, shows low thermal expansion, resists very high temperatures, is quite immune to the effects of high radiation and is chemically inert. Potential uses are in brakes, drive-train components and high-temperature structural elements.
For more information on the Mars Pathfinder mission, contact Alice Wessen
at the Jet Propulsion Laboratory.
Call 818/354-4930 E-mail: Alice.S.Wessen@jpl.nasa.gov
For more information on assistance
with the Mattel Hot Wheels Sojourner JPL Mars Rover Action Pack toy, contact Joan
Horvath at JPL.
Call 818/354-7431 E-mail: email@example.com
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