Mars Exploration Rovers (MER) Spirit and Opportunity have surpassed their designed mission lifespan by an astonishing six years, but don’t let that fool you into thinking their mental capacity is suffering.
Far from it.
With help from the MER mission controllers at NASA’s Jet Propulsion Labs (JPL) in Pasadena, Calif., our two tenacious robotic explorers are getting smarter with age.
But how can they be getting smarter? It’s not as if any of the hardware has changed; they can’t have more memory slotted into their USB ports (as they don’t have USB ports or a Radio Shack nearby).
Also, the Red Planet isn’t exactly a good host, throwing dust storms at the wheeled explorers, taxing their power supplies and, for Spirit, creating sand traps. Understandably, it’s not only their wheels, joints and solar panels are showing signs of attrition; their on-board computer systems are being pushed to the limit too.
The answer lies in the more sophisticated software beamed to the rovers so they can carry out more sophisticated tasks. And in the case of Opportunity, it’s now choosing which rocks it should study without consulting mission control.
Yes, in a manner of speaking, Opportunity is thinking for itself; the first space robot to select observation targets automatically.
After being upgraded, Opportunity’s computer can study photographs taken with its wide-angle navigation camera, scanning for rocks that fulfill pre-defined criteria. When a target has been found, the robot will take a series of images through different color filters with its narrower-angled panoramic camera.
It’s basically looking for strange-looking rocks (to scientists, “strange-looking” means “very interesting”), grabbing a closer look and then flagging them for further study. In the past, images had to be sent back to Earth to be studied by controllers before a decision could be made to do a follow-up study, often days later. Now these decisions are made ‘on the fly’ by the rover, cutting us humans out of the loop.
“We spent years developing this capability on research rovers in the Mars Yard here at JPL,” said Tara Estlin, rover driver and leader of the development group who developed this artificial intelligence (AI) software. “Six years ago, we never expected that we would get a chance to use it on Opportunity.”