Had to lengthen the side plates and tracks.
I fastened the two completed tracks to a base plate and drove it around.
While it had plenty of climbing power, it flipped over too easily. Also learned for this type of configuration an uneven number of tracks are required. I machined a plate for an even number of tracks and the center sprocket didn’t line up and mesh with the tracks. Darn!
A third prototype is currently in the cnc.
An uneven number of tracks are required? Guess I need to look at track designs a little.
Yeah, this mechanical stuff seems to take a few revs! I see in my jaws that now I need to move the rear microswitch forward so that it stays in contact with the object (target).
Alan KM6VV
Since your sideplates are so beefy, why don’t you build-in a way to take up slack and adjust track tension? Like, SLOTS! This can make the adjustments for inevitable track stretch or sag very simple, as well as make disassembly for maintenance or upgrades possible.
It could even be spring-help tension, allowing for some ‘give’.
And as for the uneven number of track pieces, you could always make the wheelbase just a bit longer, or shorter.
One other minor issue: the track may not ‘wrap’ around the driving wheel enough, under heavy load and with a possible loose or slightly slack track, the drive wheel could slip inside the track. Over time, this will chew the sprocket teeth down to nubs.
Raising the drive sprocket to enable more track wrapped around it will ensure the sprocket gets a good ‘bite’ on the track, reducing the possibility of slippage.
These tracks are designed in a way that virtually eliminates stretch.
Hmmm, true, I’ve never seen my Tri-Track stretch even a little bit. Still, a slotted axle hole would help make maintenance or upgrading easier, right?
And I still think that having more track wrapped around the drive sprocket would help.
Not an axle hole, an idler hole, if possible. Or simply a spring-loaded idler?
Alan KM6VV
Wow, thanks for all the great ideas. The current set I made Monday are really working well. I had to stretch the track plates out a bit and then redo them cause the larger center sprocket has different engagement 180 degrees out from the top (12 o’clock) forcing the tracks to be an uneven number.
So far, the latest set has lots of power and climbs up and over objects very easily. Again, I am using a 42mm 24vdc motor with 49:1 reduction. Had to machine custom hubs for the .3125 shaft.
I’ll get a few pictures up soon.
Not following the need for an odd number of tracks, and the “different engagement” stuff. It’s usually a simple calc from the pitch radius to get the Ctr-Ctr distance between pulleys (or even gears). Are tracks different?
Alan KM6VV
The top picture shows the two sprockets available for Lynxmotion tracks. The small sprocket has the same type teeth engagement at 12 o’clock and 6 o’clock. Note on the larger sprocket, teeth engagement is different.
This isn’t a problem for normally designed robots but in my case… I always have to do things differently 
An uneven number of tracks cured the problem.
The next pictures show the current track design. The robot platform is crude but works well until I am ready to take it to the next step. I cnc’d the motor mounts as well. I’ll be adding a second battery to get closer to the motors rated needs of 24vdc.
Anyone have any luck transmitting video? I’ve purchased several transmitters over the last few years and all seem to have the same trouble, get a few walls between the receiver and transmitter and the video gets really bad really quickly. I’ve tried transmitters all the way up to 2 watts (rf power) and always seem to have the same results. I understand about “line of sight” and the problems associated with it. Has anyone found a better way? I’m not very experienced with data links so something plug and play would be awesome.
I see. The sprockets are “alternating”, or something like that. I should get a sample to experiment with!
good looking boogies.
Alan KM6VV
Looks really sturdy and business-like. I would be interested in hearing how it goes, I still have misgivings about there not being much track wrapped around the drive sprocket. If that isn’t a problem, then great! This looks like it could handle quite a payload.
I’ve ordered some 5052H aluminum .090 thick. I’m going to form a shell around the chassis inside the tracks using a sheet metal brake. There will be a camera mounted in the nose with pan and tilt. I’m going to keep as much of the body inside the track dimensions so the robot can drive under obstackles without getting hung up.
I ran the robot all over the yard yesterday and the tracks are working great. No slipping at all. The motors have plenty of power to turn the bot, even sitting on the carpet it spins with ease.
I’ll post more pictures when I’m a little further along.
Incredibly tempted… 
should be a good CNC machine! But then I’m preferential to daVinci…
Alan KM6VV
I looked at those right-angle drives for my new 6WD ATV (RoboMagellan).
SuperDroid, right?
Nice looking drives!
I wouldn’t mind trying out a pair of those tracks!
Crazy camera angles!
Alan KM6VV
Yeah, gotta love the iPhone camera. Lol
I ran the second set on the cnc last night. As soon as my
Box o’ goodies come from Lynxmotion I’ll build up the second
set.
What does that RobotMagellan look like?
Can you post a picture?
Still in early chassis build, but I will be posting pictures, probably some in a day or so.
Alan KM6VV
I like it! For weight reduction, right?
I got a pix of my Robomagellan 'bot chassis posted, under Rovers/4WD. (Need 6WD!)
Alan KM6VV