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Further damage to Curiosity’s wheels

Curiosity wheel comparison of damage
For the original images, click here for the top photo and here and here
for the bottom photo.

The photo comparison to the right, created from high resolution images taken by Curiosity on Mars two months apart, provides us a new update on the state of the rover’s damaged wheels. It shows damage on the same wheel that I have been tracking for several years.

The numbers indicate the same treads, or grousers as termed by the science team. The “+” sign indicates spots where new damage has occurred since the previous photo.

The top photo was taken on June 3, 2022, and was the first to show new damage in more than five years. The bottom photo was taken on August 6, 2022, and shows that another small piece on the same grouser has broken off during the past two months.

Other than this change, however, the rest of the grousers appear unchanged. Moreover, a comparison with an earlier image of this same wheel taken in the summer of 2021 shows that grouser #6 as well as the unnumbered one just below appear also unchanged.

The damage in grouser #5 however is still concerning, and reflects the increasing roughness of the terrain as Curiosity climbs higher and higher on Mount Sharp. Though the science team has been very careful since the rover’s first few years on Mars to travel around obstacles that could damage the wheels, it apparently is becoming harder to do so.

However, even if this wheel eventually loses all the metal between the zig-zag grouser treads, the science team has said it has “proven through ground testing that we can safely drive on the wheel rims if necessary.” The team as also said they do not think that is likely, at least not for a long time, and based on the rate of damage documented by these pictures, this appears very true.


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  • GaryMike

    Metallurgists and design engineers still haven’t mastered contact with the environment(s) for which they were hired to manage.

    Models aren’t reality.

    How many rovers have had this same problem?

    A seemingly shallow learning curve too long on the Time axis.

  • GaryMike: I think your comment might be a bit unfair. As far as I know, no other rovers have had this problem, and after it was spotted on Curiosity about seven years ago the design of Perseverance’s wheels was reworked to account for it. I do not expect Perseverance to experience any wear like this.

  • M Puckett

    Mow many miles of wear does that damage represent?

  • M Puckett: The rover has traveled 17.7 miles over ten years, but that isn’t really a good guide. Almost all the damage occurred in the first four years or so, before engineers realized they needed to change how the rover traveled over obstacles. Since then there was little additional damage until the last six months, when Curiosity began moving into higher elevations where the terrain is rougher.

  • Col Beausabre

    This old tanker says “Shoulda had tracks” – and before somebody brings up track tensioning, in the Challenger, that is accomplished by pulling a lever and the rest is done automagically

  • Edward

    Robert Zimmerman Wrote: “GaryMike: I think your comment might be a bit unfair. As far as I know, no other rovers have had this problem …

    The previous rovers were smaller and lighter. Curiosity was a bold advancement in size, weight, and terrain. It is one of those learning experiences that builds character.

  • GaryMike

    This is nothing about nothing.

    Years ago, a State university wanted me to join their metallurgy Dept.

    I look at those wheels and I see “fail”.

    Sorry, I see “fail”.

    I’m nothing, if not nothing.

  • GaryMike

    Drama has a role in persuasion.

    I still see “fail”.

    “Hey, those rocks are going to be soft. right?”

  • Col Beausabre observed: “Shoulda had tracks”.

    This might be more interesting than seems at a glance. I saw a sandbox demonstration of wheels v tracks, and, as expected, tracks won.

    But there would only be two tracks, and if one fails for whatever reason, the vehicle is immobile. Two critical failure points (one each track), any one of which will render the vehicle essentially useless.

    Curiosity has six wheels. Six critical failure points, so maybe some margin to work with. It seems even if one wheel fails completely, the vehicle would still be mobile.

  • wayne

    Blair / Col Beausabre:
    –yowza, just spent an inordinate amount of time at YT watching videos on “tracked vehicles.” Very interesting stuff, although short on technical specs, (at least the ones I watched)
    Can I assume ‘tracked-propulsion’ is a fairly well-developed technology?
    Off the top of my head– alternative methods feels like a weight limitation thing’ in play??

  • Edward

    Failure, yes. That is the point.

    The wheels should not have seen damage like this. Due to this damage, Curiosity’s course has been detoured away from areas that the scientists preferred to examine to areas that they were not as curious about. Even now, Curiosity is on one such detour.

    We can only ponder what we could have learned had the wheels been strong enough for the terrain that Curiosity should have been able to traverse.

  • “We can only ponder what we could have learned had the wheels been strong enough for the terrain that Curiosity should have been able to traverse.”

    I think you will be able to as some people in a few years.

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