Robot Geologists Roaming on Mars
Call it mission impossible—for humans, that is. But, for a pair of intrepid robot geologists, trekking the surface of Mars is doable, dude.
That's why two powerful new Mars rovers—"Spirit" and "Opportunity"—recently rocketed into space, bound for the red planet to help scientists learn whether there was once life on Earth's nearest planet neighbor.
|
After bouncing to a stop, the lander's pedals unfold and the Mars Exploration Rover drives onto the surface of Mars.
(Photo courtesy: NASA)
|
Identical, 400-pound twins, the robots are loaded with scientific instruments to search for signs of water in Mars' past—minerals that form under wet conditions, old lakebeds, deposits left by hot springs—that could signal past life.
Robots are ideal space explorers. They don't have to worry about oxygen, extreme temperatures, radiation or other conditions hostile to humans. Still, getting to Mars isn't easy—only 11 of 34 Mars missions have succeeded. A big problem is the alignment between Mars and Earth, which makes it possible to launch a Mars mission only every 26 months.
The 2003 launch window—May to mid-July—was "the best opportunity in 20 years," says Dave Lavery, National Aeronautics and Space Administration program executive in charge of developing technology for exploring Mars and for other robot missions. A cycle of very difficult launch opportunities begins in 2005.
For that reason, NASA took advantage of the 2003 launch window. The rovers were launched separately from Cape Canaveral Air Force Station in Florida to increase odds at least one rover would make it to Mars' surface.
This Rover Rocks (And Rolls)
Getting to Mars—it takes six months—is just the first challenge. To land, the spacecraft must quickly slow from its travel speed of 13,000 mph. A parachute pops out and rockets fire to ease the craft through the Martian atmosphere. Even though airbags inflate to cushion the landing, the lander spacecraft will probably bounce and roll over the planet's surface for about half a mile before coming to a stop.
After all that rolling, the lander next must bring itself to an upright position. How? It's pretty simple, actually: The lander, a lightweight shell that protects the rover, is shaped like a pyramid and uses its three sides, or "petals," to hoist itself up. Each petal hinge has a motor strong enough to lift the entire craft—combined lander/rover weight is 1,200 pounds on Earth, only 437 pounds on Mars—so no matter what side it comes to rest on, the vehicle can get upright.
|
Stowed in the nose cone of this Delta II rocket, the Mars Exploration Rover blasts off from the Kennedy Space Center in Florida. It's destination: the planet Mars.
(Photo courtesy: NASA)
|
A cool piece of engineering makes that happen: Sensors detect which way is down (toward the surface of Mars) by measuring the pull of gravity. The rover computer commands the petal in the best position to right the spacecraft to open and get to work. Once the base petal is down and the craft is upright, the other two petals open and adjust so that the six-wheeled rover can drive off smoothly and begin exploring Mars' terrain.
The rover is solar-powered, so it works from Martian sunrise to Martian sunset. In one Martian day (24 hours, 40 minutes), the rover can cover the distance of a football field. Perhaps its most important tool is the RAT—short for "rock abrasion tool"—a robotic arm for grinding rocks. The RAT scrapes away the superficial exterior of the rock to expose inner areas that hold clues to Mars' ancient geological history.
Like any explorer, the rover needs a daily routine. A typical rover day begins with a morning wake-up triggered by an on-board alarm clock. Commands are received from Earth via the rover's antenna. In the afternoon, the rover sends its data to scientists and engineers back on Earth.
Sounds easy, but it's not. For one thing, a command from Earth takes 20 minutes to 45 minutes to reach the rover, depending on Mars' position. The rover can only send data directly to Earth during a three-hour window, and the data transfer speed is typically slower than a standard home computer modem. The rover has another way to send information—it can transmit data to one of the two spacecrafts orbiting Mars for relay on to Earth—but the rover can talk to an orbiter for only eight minutes of the day.
Since communication is such a problem, the robot has to be "smart"—it must know ahead of time how it will react to situations it encounters.
"It's not like you can sit there and remotely drive the robot," says Lavery. "You have to build a lot of intelligence into the machine." Cameras provide distance and other information that helps the robot maneuver through a Martian landscape and avoid crashing into boulders and rocks.
The rover is expected to work for about 90 Martian days before an increase in distance between Mars and the sun, along with a buildup of dust on the rover's solar panels, will shut it down.
Coming Space Attractions:
Robots 'All Over the Place'
As you can see, engineers had a lot to think about as they designed the rover. It needed to fit inside the spacecraft, work on its own for long periods of time, be smart enough to avoid boulders and cliffs, and survive frigid Martian nights which get as cold as minus 140-157 degrees Fahrenheit.
To solve those problems, engineers did a lot of planning and testing. Among other things, they tested a prototype rover in many different situations on Earth. The actual Mars rovers were tested in conditions simulating Mars' air pressure and temperatures.
Future Mars rovers will be even smarter. They'll probably be able to reconfigure themselves to the terrain. A rover may have an adjustable shoulder, for instance, that allows it to drop low to the ground or to elevate itself to navigate through a gully or crater. Rovers may be able to meet up with other surface vehicles. Teams of robotic rovers might work together to build bases on Mars or lay other groundwork to prepare for human visits.
Over the next decade or so, robots may be sent to space to build telescopes, explore other planets and work with astronauts on the space station and other missions. Scientists are especially intrigued by Europa, one of Jupiter's moons, because it may have an ocean under its icy crust. A robot that could drill several kilometers through Europa's ice, then explore the ocean like a submarine, would get answers to scientists' questions long before human missions could occur.
"Over the next couple of decades you'll see robots all over the place in space," says Lavery. "The whole reason we're exploring now with robots is as a precursor to human missions, paving the way for eventual human mission. It's not a case of robots versus humans, it's robots, then humans."
To follow the progress of the Mars rovers, see http://mars.jpl.nasa.gov/mer/
|
Roller-Coaster Airplane Helps
Robot Inventor Find Her Niche
In high school, Corinna Lathan mostly played sports and hung out with friends. In college, she dropped freshman physics because it was too hard. Now she's in some boring, dead-end job-right?
Wrong.
|
Corinna Lathan flies in NASA's KC-135 astronaut training plane.
(Photo courtesy: AnthroTronix, Inc.)
|
Cori, 35, runs her own robotics company. She designs virtual reality experiments for astronauts in space, and uses Super Mario-style video programs to help disabled kids. And that's only the short list.
The truth is, the Waynesboro, PA native turned out to be a whiz at something she was really interested in—using telecommunications and consumer electronics for some very outside-the-box applications.
But let's go back to the school thing.
"High school to me was purely social, playing sports and hanging around," she said. "My parents struggled with that."
As a college freshman, Cori took on too much and ended up dropping physics, which she found hard and boring. Second semester, she got a "D" in biology.
She got herself on track a few years later. In fact, let's call her "doctor." That would be for the Ph.D. in neuroscience from MIT—the Massachusetts Institute of Technology. She also has a graduate degree in aeronautics and astronautics and an undergraduate degree in biopsychology and mathematics.
Cori has studied and taught all over the world, written many papers and grants, won lots of honors and worked to bring more women and minorities into the engineering fields. Her list of accomplishments runs to 12 single-spaced pages.
What happened between high school and those 12 pages? The Vomit Comet.
Otherwise known as KC-135, the Comet is a plane NASA uses to train astronauts. Like a roller coaster in flight, the plane shoots steeply upward, then down, creating a 25-second period of weightlessness at the top of the flight arc. (The actors in the 1995 movie "Apollo 13" endured weeks of filming aboard the plane and thought the Comet's nickname well-deserved.)
As a college student, Cori talked her way into a summer job at the Ashton Graybiel Spatial Orientation Laboratory at Brandeis University. To test space experiments, she got to fly on the KC-135.
That helped her realize her calling.
"I knew that I wanted to do space research for graduate school," she says. "What interested me the most was the effect of space on humans."
She studied the brain, how it perceives and learns, and how space flight and weightlessness affect those perceptions. She decided to turn her knowledge into high-tech inventions here on Earth. At age 31, she started a company to develop robotic toys to help children in physical therapy.
|
Corinna Lathan, with one of the robots her company designs.
(Photo courtesy: AnthroTronix, Inc.)
|
"I realized there was a huge need for basic technology, that the consumer electronics revolution hadn't come to rehabilitation yet," she said.
Her company, AnthroTronix, Inc., develops wearable computers, motion sensors and voice activation systems that let children interact with therapeutic robots.
For example: A child with cerebral palsy needs to work her muscles to keep them from getting stiff or useless. To interact with Cori's robots, the child wears an ordinary-looking glove and cap embedded with sensors and raises her arms or waggles her head to make the robot do the same. The robot might say "Great job!" or give other feedback.
Cori's newest robot is the CosmoBot™. A Super Mario-style video version of the CosmoBot is like the Nintendo game—CosmoBot runs along a moonscape and captures stars and planets—but is easier for a disabled child to control. The game can be programmed for each child's needs. CosmoBot might not make the desired motion, for example, until the child lifts both hands high enough to achieve the therapy goal.
AnthroTronix also is developing the "Virtual Reality Buddy," which tracks eye movements in autistic children to help them learn to interact with their world. The idea is to reward the child when she makes eye contact with people in the virtual environment.
Cori is also working on a virtual reality headset she hopes will be used in the International Space Station to determine how astronauts' perceptions change when they're in space.
Being a woman in a field traditionally dominated by men hasn't been easy. "Unfortunately, engineering has traditionally been white male," she says. Engineering also suffers from what Cori calls "a visibility problem" that has kept the numbers of those entering the field down.
"People want to be doctors and lawyers because there are great TV programs that feature doctors and lawyers and not one that features engineers—except maybe 'Star Trek,' and it's only watched by a dedicated few," she says.
Robotics is a field with room to grow, "lots of interesting problems to solve" and plenty of challenges ahead, Cori says.
"We haven't done robots well yet," she says. "The flaw has been in the interface, the human/robot interaction. There are lots of robotic platforms but very bad interfaces to control them. That's a huge opportunity for us."
|
Xtra Real People
Name: Dave Lavery
Age: 43
Title: Program executive
Company: National Aeronautics and Space Administration (NASA)
His real job: In charge of developing technology for exploring Mars and for other robotic missions; ran NASA's robotics research program for 12 years. To see how robots perform in conditions too harsh for humans, he's sent them into active volcanoes in Alaska, under the Antarctic ice shelf and worked with them in a simulated zero-gravity environment.
Why he chose this career: "My heroes were Neil Armstrong and John Glenn, but my poor eyesight would not let me pass the physical evaluations required to become an astronaut. So I work on machines and, by proxy, have them explore space and experience space for me. I get to play with the coolest toys on and off this planet."
School: B.S., Computer Science, Virginia Tech (Virginia Polytechnic Institute and State University). Graduate work in Artificial Intelligence.
What he does for fun: Biking, mountain climbing, amateur metal-working. Now building a steam locomotive in his garage. Despite working on super-advanced technology at NASA, at home he still has ancient Beta-format videotapes and vinyl records. "The irony of this is not lost on me," Lavery acknowledges.
Advice: "Never, ever, ever give up. I wanted to work in space. I couldn't do that, but I didn't let that stop me. I love my job. I want to come here and do this every single day. Find the thing that makes you that excited. Go after it and never give up. If a roadblock's out there, find a way around it. The paycheck, the financial rewards, should be second-order concerns."
Recommended academic path: Math, science, technology, engineering, computer science, artificial intelligence—all are ways to get there. But NASA also employs artists, journalists, English majors, accountants, physicians, nutritionists and others, so there are many opportunities for those interested in space exploration.
Driving Force: "Being involved in a program seeking to expand human knowledge, to better understand our place in the universe, the ultimate question of why we're here. Having a tiny part to play in the answer of that question is very exciting and inspiring."
Predictions: "Over the next couple of decades, you'll see robots all over the place in space."
|
How Robots Work
Robots are machines and automated systems programmed to do tasks that would otherwise be done by humans. A vending machine is an example of a robot—it identifies the coins you put in, dispenses the item you selected, and returns any change due. A bicycle, on the other hand, isn't a robot. It gathers no data and makes no decisions based on that data but simply responds to the mechanical pressure you put on the pedals.
Like any machine, a robot can have any number of mechanical and electrical components and its systems can be simple or highly complex. A remote-controlled toy car, for example, is a fairly simple robot. It reacts to commands transmitted electronically from the controller device to a receiver in the body of the car. A microwave is a bit more complicated, but it too responds to commands on a control pad that determine how long it dispenses heat and at what power.
By contrast, a spacecraft's automated navigation system is a complex and interrelated network of sensors, computers, hardware, and software. Sensors on board the Mars Rover spacecraft, for example, measure gravity's pull as the spacecraft is landing. That information is fed to the Rover's onboard computer. The computer commands one of the Rover's three sides, or "petals," to right the spacecraft so it can drive over Mars' surface and begin exploring the planet's terrain. (See "Robot Geologists Roaming on Mars.")
If you're interested in robotics, a good place to start exploring this subject is with programs and activities that provide you with real-world experiences. An example of such a program is NSTEP's TechXplore, a program and competition that connects teams of students with scientists, engineers, and technology professionals from electronics, telecommunications, and high-tech companies to explore the world of technology. If you want to establish a TechXplore team at your school to explore robotics, artificial intelligence, or other topics send an email to TechXplore@nationalstep.org.
Also, a number of colleges and universities have active robotics research programs, or offer introductory courses in robotics. Virginia Tech's Mechanical Engineering Undergraduate program, for example, offers course #4524—Introduction to Robotics and Automation.
|
The nose cone of the rocket separates during the launch phase and the Mars Exploration Rover is sent on a seven-month journey to Mars.
(Photo courtesy: NASA)
|
|
Robotics Glossary
|
Artificial intelligence: The science and technology of creating "smart" machines or systems, meaning the machines go through processes similar to those humans use when they make decisions or react to their environment. Typically, smart machines gather and analyze information, then make a programmed response to that analysis.
Controller: A device that monitors and controls a robot, usually by transmitting commands electronically to a receiver in the robot.
Humanoid robot: Robots designed to act, move, and look like humans. They may, for example, walk and climb stairs, recognize human faces and gestures, and react to those social cues.
Industrial arm: A robotic device used in heavy manufacturing, usually to perform repetitive tasks; early uses of industrial arms include automotive assembly lines.
Receiver: A device on the robot that
|
receives and processes the electronic signal sent by the controller.
Robot: Machines and automated systems programmed to do tasks—often in reaction to their environment—that would otherwise be done by humans.
Sensor: Systems or devices that allow robots to perceive and process information about the environment. Mobile robots, for example, may use infrared or ultrasonic sensors to detect and avoid moving or stationary objects. (Infrared sensors emit invisible light waves and determine an object's distance by measuring its reflection of those waves. Ultrasonic sensors emit sound waves and measure distance by calculating the time it takes for the waves to strike the object and return to the sensor.)
Virtual reality: The interaction of humans and computers through programs that simulate a real-world or three-dimensional environment. (Think "Matrix" or just about any video game.)
|
|
Part I of TechXtra's special feature on Robotics appeared in the
April 2004 issue.
|
TechXtra®
Published by the National Science & Technology Education Partnership (NSTEP)
formerly Electronics Industries Foundation
2500 Wilson Blvd.
Suite 210
Arlington, VA
22201-3834
(703) 907-7400
www.nationalstep.org
President
Barbara L. Wortmann
Marie Wiggins
Director, Educational Initiatives
Executive Editor TechXtra
Debra D. Bass
Writer
Eileen Putman
Web Design
Chris Korin
|
NSTEP is grateful for the support provided for this issue by:
Panasonic Consumer Electronics Company
Philips Electronics
Consumer Electronics Association
Active International
Cornell Dubilier Electronics
Editorial Advisory Committee
Jennifer Martino, PhD, science teacher, Governor Livingston High School
John E. Riley, Radiation Safety Consultant, Just-In-Time Industrial Hygiene
Douglas A. Tyson, chemistry teacher, Benjamin Banneker Academic High School
Gary Ybarra, PhD, Director of Undergraduate Studies, Duke University
|
TechXtra, a free e-newsletter published periodically from September through May by the National Science & Technology Education Partnership (NSTEP), brings new technology to life for students and their science, technology and math teachers. And, it brings life to technology with a close-up look at the jobs, career paths and education of the people who make it all happen.
National Science & Technology Education Partnership (NSTEP) is a nonprofit 501(c )3 organization that is dedicated to developing tomorrow's technology leaders.
|
|
