Sojourner - Mars Pathfinder mini-rover

[Retired_for_now]

So, in filling out the list of missing paper models (the NASA version still on-line is almost not worth doing) here's the Sojourner mini-rover from the Mars Pathfinder mission.

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Pathfinder was the first mission to try the beachball landing system, subsequently used for the larger rovers Spirit and Opportunity.

Posted for download in the Sci Fi & Real Space section. Scaled at 1:12 and 1:15 if you want to match Erik & Ton's larger Mars Rovers.

Looking forward to your own builds, comments and modifications. Obvious place for mods is the suspension - adding 3-D, axles/pivots, motors inside the wheels, variant wheel mounts (rather than the bend and glue to the inside of the wheel as drawn), etc.

Yogi

[Paperwarrior]

Yogi,

This is another great subject you've provided for us. Thank you for your work and dedication.

[Retired_for_now]

Anything to help you make the deployments go faster, Jeff.

Yogi

[Retired_for_now]

Ok - mea culpa. Don't rescale models late at night. The 1:12 scale Sojourner is correct. The 1:15 page is actually 1:9.6 scale (let's see, numerator/denominator/terminator/...??). You'd think I'd notice that 1:15 should be SMALLER than 1:12. Will fix and repost the corrected one for anyone looking to build a set with the Spirit/Opportunity Rover Models.

Yogi

FIXED.

[jparenti]

Just put one together myself -- it was a quick and easy build. Very happy with the results, and I think I'll look into complicating the suspension for my next trick. :)

A strange historical note: The Pathfinder lander failed before the rover did, and according to the rover's programming (and later photographs of the site from MRO), Sojourner apparently continued circling the dead lander trying to get a signal. No one really knows how long it kept trying to talk to us. It may have been a while, considering the batteries had died earlier and the rover relied on direct power from the solar panel after that.
I always thought that image was a little sad, the little rover still trundling around trying to talk and receiving silence. (Uh oh, I'm anthropomorphizing spacecraft again.)

[jparenti]

And here it is. I already tried a modification, the colored edges on the solar panel (color camera calibration target, perhaps?) drawn in Powerpoint. Colors are not an exact match of width and pattern, and I may need to slim it down a bit more, but you get the idea.

http://i79.photobucket.com/albums/j136/jparenti/Mars%20Pathfinder%20model/DSC00270.jpg

I think I may try playing with the suspension next...

[Retired_for_now]

Now that is way-cool J. Very nice mod - I should probably add that to the file, along with some rework on the aft end instruments.
If you use small cylinders inside the wheels (motors?) with a pin to the bogie mounts, then articulate the pivots, add small batteries, some RC gear ... sorry, getting carried away.

Well done!
Yogi

[jparenti]

The aft end instruments are fairly complicated looking. I've never looked into it closely, and the best line drawings I can find are very simplistic. I do have decent pics of the APX, but honestly it's just a cylinder. It's the mounting I'm curious about.
Luckily, I have a little more help with the bogie mounts. I'm going to model the articulation after the Hot Wheels version that was released back in 1997 (of which I have two) -- it's accurate enough for my purposes, and if you've ever played with one, you'll see what I mean. I was always really shocked at how good the details were on those little "toys". (Of course, the reason we've never seen decent blueprints of the rover is because of the licensing agreement with Mattel -- arrg!) I'm thinking short pieces of wire for pins should do the trick for joints. We'll see if I can make it sturdy.
Motors...hmm. ... :D

[Retired_for_now]

Yah, had one of those little rovers - haven't seen it since hurricane Ivan. They are pretty neat - and apparently no longer being made.

Press on - feel free to redraw and post a version with the improvements (free pass to everyone for improvements to any of my designs, so long as you post the good stuff for the rest of us). Or, I'll get around to adding them eventually.

Yogi

[jparenti]

If you still have the Powerpoint file, could I use it? I'm going to attempt to redraw my side rails and graft them to the model (which should help with the sizing issue. I'm still examining ways to mount the suspension as well -- stay tuned...