They said it couldn’t be done… Well actually I was the one who said it. But I was referring to the older version of the rover. But when I added an inch to the length it changed things considerably. I have tested the tracks and they are working well. There is still a little bumpiness, we refer to it as whump whump whump, when the vehicle is in motion. lol But it’s much better than running with no idlers at all. The ground clearance is about 1/8" more on the tracked version. Here are the images.
Here is the rover next to the wheeled version.
Here is an isometric view. I made the parts from clear lexan so it would be easy to see how it is installed.
Ok well, the first attempt didn’t go so well. There was just no way to smooth out the ride. It would probably be ok for dirt and grass, but on a smooth surface it was way too bumpy.
The 4WD Rover was designed without taking a track add on kit into account. The problem is the wheelbase was too far apart for 22 links and too close together for 23 links. So I used 23 links and had to add a small sprocket with idler to take up the slack. The thing now has 1.375" of ground clearance. Not too bad…
The pro’s are: It’s smooth running! It will bolt right to the 4WD chassis. It’s not bad looking.
The con’s are: The added cost for the small sprockets and idlers. It’s not a traditional tank set up. There is less ground clearance than the other method.
I think it looks great. I like the look of your first prototype a little bit better, but would go with your new design as you say the ride is a lot smoother. Wonder what it would look like with with 2 idlers? Just kidding
I’d go with the first design. It should have better capability to climb over objects and have less track ground contact for easier turning on “grippy” surfaces. The track on the first design is more like a tank, where as the second is like found on tracked construction/excavation machines which generally operate on smooth surfaces.
I also have been wondering how a tracked version of the rover would look. Have you tested this (either 1st or 2nd design) on carpet? I’m wondering how it would handle a pivot in place (.e. Left=Fwd, Right=Rev), or do you have to just stop one side to make a turn, in order to deal with all the additional friction? I have some R/C tanks, and performance on carpet is miserable!
One thing that comes to mind, maybe can get away with two motors (maybe the higher-torque one) instead of four, freeing up some chassis space, always a plus! Sure would like to see a video - preferably on hard surface and on carpet…
At any rate, I’m hoping you pursue this idea - I’d probably jump in if the kit was offered… I’m still weighing the +/- of the different motive platforms before I order. I like the ‘sexiness’ of a legged platform, but am leaning towards wheeled/tracked platform, so I can concentrate more on the robots tasks once it gets to a location, and less on the intricacies of getting it to a location. Make sense?
One thing about your company, this forum and the great group involved, I’m never short of things to think about…
I don’t like it. It looks to symmetrical to me. How hard would it be to move the idler back a few inches to an offset triangle look, like the J5 tracks? Moving the idler back may cause more slop on one side of the idler, I don’t know.
I guess I will need to find all the parts I made back when I was working on this in order to make videos to illustrate the uneven movement of the track segments in the first design. I thought it was unacceptable.
Tracked bots will always have more trouble turning in place on carpet compared to tile floors. The 4 motor tracked version of the rover will be stronger than the TriTrack version. That is a fact.
I gotta admit I’d really like to tinker with this platform - it would be slick to get acceptable performance out of the 1st configuration. I agree with the others - it just looks better to me, also. I am looking forward to more information from you.
