Curiosity adds reverse driving for wheel protection

Feb 20, 2014 by Guy Webster
This map shows the route driven and route planned for NASA's Curiosity Mars rover from before reaching "Dingo Gap" -- in upper right -- to the mission's next science waypoint, "Kimberley" (formerly referred to as "KMS-9") -- in lower left. Credit: NASA/JPL-Caltech/Univ. of Arizona

(Phys.org) —Terrain that NASA's Curiosity Mars rover is now crossing is as smooth as team members had anticipated based on earlier images from orbit.

On Tuesday, Feb. 18, the rover covered 329 feet (100.3 meters), the mission's first long trek that used reverse driving and its farthest one-day advance of any kind in more than three months.

The reverse drive validated feasibility of a technique developed with testing on Earth to lessen damage to Curiosity's wheels when driving over terrain studded with sharp rocks. However, Tuesday's drive took the rover over more benign ground.

"We wanted to have backwards driving in our validated toolkit because there will be parts of our route that will be more challenging," said Curiosity Project Manager Jim Erickson of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

The rover team used images taken from orbit to reassess possible routes, after detecting in late 2013 that holes in the vehicle's aluminum wheels were accumulating faster than anticipated. Getting to the chosen route, which appeared to be less hazardous for the wheels, required crossing a 3-foot-tall (1-meter-tall) dune. Curiosity crossed the dune on Feb. 9.

Erickson said, "After we got over the dune, we began driving in terrain that looks like what we expected based on the orbital data. There are fewer sharp rocks, many of them are loose, and in most places there's a little bit of sand cushioning the vehicle."

This look back at a dune that NASA's Curiosity Mars rover drove across was taken by the rover's Mast Camera (Mastcam) during the 538th Martian day, or sol, of Curiosity's work on Mars (Feb. 9, 2004). Credit: NASA/JPL-Caltech/MSSS

The mission's destinations remain the same: a science waypoint first and then the long-term goal of investigating the lower slopes of Mount Sharp, where water-related minerals have been detected from orbit.

The science waypoint, which may be where Curiosity next uses its sample-collecting drill, is an intersection of different rock layers about two-thirds of a mile (about 1.1 kilometers) ahead on the planned route. This location, formerly called KMS-9 from when it was one of many waypoint candidates, is now called "Kimberley," for the geological mapping quadrant that contains it. The mapping quadrant was named for the northwestern Australia region with very old rocks.

While the is headed for the Kimberley waypoint and during the time it spends doing science investigations there, the team will use orbital imagery to choose a path for continuing toward the long-term destination.

"We have changed our focus to look at the big picture for getting to the slopes of Mount Sharp, assessing different potential routes and different entry points to the destination area," Erickson said. "No route will be perfect; we need to figure out the best of the imperfect ones."

Curiosity has driven 937 feet (285.5 meters) since the Feb. 9 dune-crossing, for a total odometry of 3.24 miles (5.21 kilometers) since its August 2012 landing.

Explore further: Curiosity Mars rover checking possible smoother route

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GSwift7
not rated yet Feb 20, 2014
We have changed our focus to look at the big picture for getting to the slopes of Mount Sharp, assessing different potential routes


I was wondering when they would switch to this strategy. I understand that they wanted to make sure they got a good sampling of the area they landed in, but the real gold mine should be the mountain. It would be a real shame for the rover to fail before making it to the mountain, so I hope they make it.
TheGhostofOtto1923
2.5 / 5 (2) Feb 20, 2014
I was wondering when they would switch to this strategy. I understand that they wanted to make sure they got a good sampling of the area they landed in, but the real gold mine should be the mountain. It would be a real shame for the rover to fail before making it to the mountain, so I hope they make it.
Hey just think - rovers in the near future will be able to land right where we want them.

"Development of Supersonic Retro-Propulsion for Future
Mars Entry, Descent, and Landing Systems"
http://www.ssdl.g...5046.pdf

"SUB_SCALE FLIGHT TESTS at Earth by 2016"

"40 TON PAYLOAD"

"Engines capable of throttling down to 20% of full thrust"

"four orders of magnitude improvement in landing accuracy (meters)"

-But Im sure that they will have improved wheel design by then. To accommodate 40 tons that is.
TheGhostofOtto1923
1 / 5 (1) Feb 20, 2014
Yo g - heres another one which ended in 1996

"The DC-X, short for Delta Clipper or Delta Clipper Experimental, was an unmanned prototype of a reusable single stage to orbit launch vehicle built by McDonnell Douglas in conjunction with the DOD's SDIO from 1991 to 1993. After that period it was given to NASA, who upgraded the design for improved performance to create the DC-XA."
http://www.youtub...cTFfV3Ls

-Already obsolete-
GSwift7
5 / 5 (1) Feb 21, 2014
What's your point Otto?

You keep acting like you're the only person who reads this stuff.

Here's a good quote from the introduction of the paper you linked to:

Only minor improvements in landed mass and accuracy beyond MSL are believed to be possible using a similar entry system architecture


You do understand that the paper is just a grocery list of all the technical barriers to landing a heavy load on Mars, right? Afik, most of the problems they discuss in that paper still remain unsolved. In fact, I'm not even aware of any upcomming Mars mission right now, much less some kind of super-lander with advanced technology that doesn't even exist yet.

The development cycle for that stuff you linked to isn't in the current NASA budget either. The only money on the table right now for Mars missions is a little bit towards a sample return mission in partnership with ESA.
TheGhostofOtto1923
1 / 5 (1) Feb 21, 2014
You do understand that the paper is just a grocery list of all the technical barriers to landing a heavy load on Mars, right? Afik, most of the problems they discuss in that paper still remain unsolved. In fact, I'm not even aware
Yeah I know you're not aware.
The development cycle for that stuff you linked to isn't in the current NASA budget either.
Youre GUESSING again g.

"SUB_SCALE FLIGHT TESTS at Earth by 2016"

SpaceX falcon 9
"first stage booster would do a deceleration burn to slow it down and then a second burn just before it reached the water. When all of the over-water testing is complete, they intend to fly back to the launch site and land propulsively, perhaps as early as 2014."

And you have to watch the vids as well.
http://youtu.be/ZxKWh7kLDzw
http://youtu.be/1wOJ9JImlRs
TheGhostofOtto1923
1 / 5 (1) Feb 21, 2014
You keep acting like you're the only person who reads this stuff.
And you don't bother to read it until it's dropped into your lap.
You do understand that the paper is just a grocery list of all the technical barriers to landing a heavy load on Mars, right?
No it's not. I explained to you what it was and gave you a quote.

"The SRP development roadmap presented here is framed around the advancement of all necessary component technologies and an integrated system using NASA guidelines for measuring technology maturation."

-It's a plan for the continued devt and integration of this tech which exists at various stages of maturation. The same sort of plan was done for Curiosity and 10 years later it was set to launch.

Please review the previous thread where this first came up .
http://phys.org/n...ion.html
GSwift7
not rated yet Feb 24, 2014
No it's not. I explained to you what it was and gave you a quote.


It's called a gap analysis. It's only a 'plan' in the sense that those are the things that would need to happen before you could do the mission. Most of it isn't happening yet, and there's not anyone actually planning to do it yet.

The falcon 9 'grasshopper' system has nothing to do with a Mars landing. That's just a reusable first stage self-recovery system, for Earth launches.

It's a plan for the continued devt and integration of this tech which exists at various stages of maturation. The same sort of plan was done for Curiosity and 10 years later it was set to launch


This sort of gap analysis is done for every mission considered for funding. The idea is to make sure the items with very long lead times will have adequate time to be completed, if the mission gets the green light for full funding. It's a contingency plan, not a full mission plan.