I’m a newbie, but I would like to know if someone has made a six wheel rover similar to the Mars Opportunity Rover. I sure would like to make one. If you have something similar, please point me the way to see it.
My reasoning is that the folks at JPL must have spent a lot of grey matter defining that suspension and articulation, and there really would be no sense in not using something similar as a starting point. As an aside, does anyone know where good graphics are availiable on this Mars Opportunity Rover? I do have a few of the Pictures as one would find on the net, but no good schematics or so. (Yes, I know that stuff is proprietary, but this is all just for hobby sake…)
While the Journey rover is indeed pretty cool it pales in comparison to the suspension system used on Spirit and Opportunity. It is based on parts from a 1/10 scale (I think it was) R/C monster truck.
Migs what you are searching for is a differentially-linked boggie suspension. The mid and rear wheels on a side have a bogie arm, and then that bogie arm is part of a sencond arm with the front wheel. The boggie arm connected to the front wheel has its pivot point connected through a differential link to the pivot point of the same arm on the opposite side. this has the effect of keeping the top platform considerably flat (level, horizontal, etc) when traveling over uneven terrain. I actually built a representation of the suspension with legos and compared a linked version against an unlinked version and was surprised/amazed at how much difference it made. it was pretty obvious that to optimize the relationships between arm lengths and angles of the boggie arms would either take some serious math or a lot of empirical testing. Lastly, one other really cool feature of the rovers is the motors for the wheels are actually built into the wheels themselves. I have sort of been picking at finding a way to do something similar with common hobby grade parts for awhile now but as of yet do not have a real solution.
Thanks for the copious info. I’m excited about doing this, and will certainly make some type of a mock-up (thinking Mecano) before a real bot. I too also thought about motor within the wheel, but it seems complicated. My moto is “first make it work then make it beautiful”.
I also appreciate the term “differentially-linked boggie suspension” since it broadens my search horizons if you understand what I mean.
that is very very cool.
Two things I notice are they did a nice implementation of the self powered wheels using “normal” kind of parts, and it doesn’t look like the center wheels are powered which is different than spirit/opportunity. I don’t quite get the $8K price tag either but, uh, what ever the market will bear I guess.
price aside though they did a nice job.
I remember there being a fair amount of information in the form of research papers and I seem to recall some white papers on or referenced by the jpl website when I was actively looking at this about 2(?) years ago. The mechanics of how it works are pretty cool.
I have found a few really good sites with detailed information. I tried to put the links in here, but since I’m new the systems doesn’t allow it. Soon enough though I’ll show you what I’ve found.
I did a science fair project on the Mars Exploration Rovers both Spirit and Opportunity. The best place for you to research is the official JPL website for the rover mission found here: marsrovers.nasa.gov/home/
Watch all the videos and read all the information. This is where I found most of my best information.
PS. Mars Pheonix lander will be on Mars in 2009. Launched Aug 4
It is based on parts from a 1/10 scale (I think it was) R/C monster truck.
