4WD2 Track Conversion

Lynxmotion Rovers, Sumo, and Tracked
1

Hello all,

I have a 4WD2 chassis that I have setup to no longer articulate (unrelated to my issue) and I would like to convert it to a track setup because:

1 - I am not happy with the turning characteristics of the wheeled setup.
2 - Using only 2 motors (instead of 4) frees up 4 outputs on my controller (I use the MAKE Controller from makingthings.com)
3 - Tracks rule.

I could really use some insight into the parts I’m going to need as far as idlers, which track width is better (or characteristics regarding width vs. performance) and any other setup info you guys may have.

Appreciate it much!

Patrick

2

Hi,

I have had the same idea.

I am planning to design a tracked bot using the A4WD chassie only and a pair of track.

Do you know if is it possible to use a pair of track (2" Wide x 21 links ~23") with the A4WD chassie?

Thanks.

3

Tracks may rule, but depending on what surface you are turning on, tracks will offer worse performance then simply 4 wheels. Any skid steer design, regardless of how many motors it has, will perform ‘poorly’ on high friction surfaces, such as asphalt. Tracks due worse because there is usually much more surface area in contact with the ground, causing much greater friction.
(Actually, its kinda scary to see a 150lb 4WD robot ‘skipping’ around on a turn in place because of that friction on asphalt.)

The easiest way I think you will be able to convert, is if you get some lexan panels, and use standoffs to position them 1.5" or 2.5" away from the side of the chassis. Then you will have to drill 3mm holes on one side for the ball bearings in the idler kit, and on the other side mount your motor.

As far as which width to choose? I’d say it all depends on your target environment. Asphalt, I think you want skinny tracks, to reduce friction. Sand, I think you want wide tracks to increase surface area. Etc.

4

As Sienna stated you would need to build up the track assemblies with idlers, and attach them to the soides of the A4WD. I have been asked for this many times, so I will see what can be done. I would recommend 2" wide tracks for smaller bots like this.

5

Thanks for the replies all. I had thought that tracks may give less turning performance than the wheels due to surface friction the four motor/tire setup was unacceptable.

I’m primarily looking for grass/dirt so I’m hoping tracks will be the ideal. I may jsut end up changing chassis’ all together to get some more real estate for electronics.

Thanks again!

Patrick

6

you could try to setup a half track type setup fo better steering and improved traction…

just a though…

7

by half track do you mean, track drive with servo steering?

8

Half Track:
en.wikipedia.org/wiki/Image:Half … ning-2.jpg

9

For this type of setup i think he would have to convert to a new chassis. But its an interesting idea.

10

Is there a possibility of a tracked rover option like the one that displayed under Products -> Tracks? Or at least schematics on how the one pictured was created?

11

lynxmotion.com/Category.aspx?CategoryID=109

12

Thanks Italian_Guy299 but I meant the a track vehicle based on the rover not the tri-track.

13

As far as we know, lynxmotion isn’t coming out with a tracked vehicle based on the 4WD2 rovers. There is already a tri-track. Why not DIY?:

http://i101.photobucket.com/albums/m51/Italian_guy299/MARCtittlepagephoto.png

14

There wouldn’t necessarily have to be a completely different chassis. Just add on to what is already there. :slight_smile:

8-Dale

15

This is exactly what I was looking for as well. Since lynxmotion has made something like that, would someone be kind enough to post the parts list and/or the schematics? Thanks.