Curiosity tests a new way to drill on Mars

March 1, 2018 by Andrew Good, NASA
NASA's Curiosity Mars rover used a new drill method to produce a hole on February 26 in a target named Lake Orcadie. The hole marks the first operation of the rover's drill since a motor problem began acting up more than a year ago. Credit: NASA/JPL-Caltech/MSSS

NASA's Mars Curiosity rover has conducted the first test of a new drilling technique on the Red Planet since its drill stopped working reliably.

This early test produced a hole about a half-inch (1-centimeter) deep at a target called Lake Orcadie—not enough for a full scientific sample, but enough to validate that the new method works mechanically. This was just the first in what will be a series of tests to determine how well the new method can collect samples. If this drill had achieved sufficient depth to collect a sample, the team would have begun testing a new sample delivery process, ultimately delivering to instruments inside the rover.

The drill is used for pulverizing rock samples into powder, which are then deposited into two of Curiosity's laboratory instruments, Sample Analysis at Mars, or SAM, and Chemistry and Mineralogy, or CheMin. Curiosity has used its drill to collect samples 15 times since landing in 2012. Then, in December of 2016, a key part of the drill stopped working. The drill was designed to use two finger-like stabilizers to steady itself against rock; a faulty motor prevented the drill bit from extending and retracting between these stabilizers.

After months of effort, Curiosity's engineering team was able to extend the drill all the way out past the stabilizers, but the motor issue persisted. The team posed a challenge for themselves: could they hack the space robot's drill so that it didn't require stabilizers?

Images of a new hole on upper Vera Rubin Ridge, Curiosity's current location, suggest this "MacGyvering" is paying off. By leaving the drill in an extended position, engineers were able to practice this freehand drilling for months during testing here on Earth. This hole at Lake Orcadie provides the first insights into how this operation will work in the Martian environment.

If the previous method was like a drill press, holding the bit steady as it extends into a surface, it's now more freehand. The NASA rover is using its entire arm to push the drill forward, re-centering itself while taking measurements with a . That sensor was originally included to stop the rover's arm if it received a high-force jolt. It now offers Curiosity a vital sense of touch, preventing the drill bit from drifting sideways too much and getting stuck in rock.

"We're now drilling on Mars more like the way you do at home," said Steven Lee, deputyprojectmanager at NASA's Jet Propulsion Laboratory, Pasadena, California. "Humans are pretty good at re-centering the drill, almost without thinking about it. Programming Curiosity to do this by itself was challenging—especially when it wasn't designed to do that."

After more than a year without the use of the Curiosity Mars rover's drill, engineers have devised a workaround and tested it for the first time on the Red Planet. More testing of the drill method is planned for the future. Credit: NASA

It hasn't been easy. JPL engineers spent many double-shifts testing the new method, including on weekends and holidays. They also had to perform "invasive surgery" on their testbed—a near-exact replica of Curiosity—installing a force sensor to match the one on Mars. The Earth-based testbed's sensor had stopped working before Curiosity's launch in 2012, but there had never been reason to replace it before now.

"This is a really good sign for the new drilling method," said Doug Klein of JPL, one of Curiosity's sampling engineers. "Next, we have to drill a full-depth hole and demonstrate our new techniques for delivering the sample to Curiosity's two onboard labs."

Leaving the drill in its extended position means it no longer has access to a device that sieves, portions and delivers the rock powder to the rover's instruments (called Collection and Handling for In-Situ Martian Rock Analysis, or CHIMRA).

JPL also had to invent a new way to deposit the powder without this device. The new solution makes Curiosity look as though it is adding seasoning to its science, shaking out grains from the drill's bit as if it were tapping salt from a shaker.

This tapping has been successfully tested here on Earth—but Earth's atmosphere and gravity are very different from that of Mars. Whether rock powder on Mars will fall out in the same volume and in a controlled way has yet to be seen.

In the days ahead, Curiosity's engineers will evaluate the results of this recent test and likely drill again nearby. If enough sample is collected, they will test portioning the sample out, using the rover's Mastcam to estimate how much powder can be shaken from the .

Though this first test of the drill didn't produce a full sample, Curiosity's science team is excited to see this step on the path back to routine drilling. There's high interest in getting multiple drilled samples from Vera Rubin Ridge, especially from the upper ridge that contains both gray and red rocks. The latter are rich in hematite, an iron oxide mineral that forms in the presence of water. Drilled samples might shed light on the origin of the ridge and the history of its interaction with water.

Explore further: Mars rover mission progresses toward resumed drilling

Related Stories

Preparatory drill test performed on Mars

February 7, 2013

(Phys.org)—The drill on NASA's Mars rover Curiosity used both percussion and rotation to bore about 0.8 inch (2 centimeters) into a rock on Mars and generate cuttings for evaluation in advance of the rover's first sample-collection ...

Curiosity rover confirms first drilled Mars rock sample

February 20, 2013

(Phys.org)—NASA's Mars rover Curiosity has relayed new images that confirm it has successfully obtained the first sample ever collected from the interior of a rock on another planet. No rover has ever drilled into a rock ...

Curiosity rover collects first Martian bedrock sample

February 9, 2013

(Phys.org)—NASA's Curiosity rover has, for the first time, used a drill carried at the end of its robotic arm to bore into a flat, veiny rock on Mars and collect a sample from its interior. This is the first time any robot ...

Testing to diagnose power event in Mars rover

March 5, 2015

NASA's Curiosity Mars rover is expected to remain stationary for several days of engineering analysis following an onboard fault-protection action on Feb. 27 that halted a process of transferring sample material between devices ...

Recommended for you

Matter waves and quantum splinters

March 25, 2019

Physicists in the United States, Austria and Brazil have shown that shaking ultracold Bose-Einstein condensates (BECs) can cause them to either divide into uniform segments or shatter into unpredictable splinters, depending ...

How tree diversity regulates invading forest pests

March 25, 2019

A national-scale study of U.S. forests found strong relationships between the diversity of native tree species and the number of nonnative pests that pose economic and ecological threats to the nation's forests.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.