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jiokl
01-19-2014, 09:57 PM
I've done a lot with the arduino, and some robotics before, mostly playing with turret styles. I now want to start building an "actual" robot. I've been designing a track based crawler, but need help finding parts, I can not seem to find any kind of small hobbyist style tracks, and just wanting to know where people find there's or what they use. I also was wondering if there are any good tutorials out there, I'd like to have it remote controlled which is also going to be new for me. I really just want to build a good base robot, any help or tips would be very appreciated.

tician
01-19-2014, 11:58 PM
Pololu sells two sizes of custom rubber tracks with the smaller version used on their really small and cute rover. They also sell the Tamiya track kit that is used in several small kits, and another very common and slightly larger track. That last track is produced by multiple manufacturers in a couple materials and with several compatible wheels using different drive options. The version Pololu sells is made from ABS and BasicATOM sells it with a rubberized material and a non-flat tread design.
For somewhat larger robots, lynxmotion sells track kits made from 2" and 3" widths of polypropylene conveyor track.
For really big robots, replacement tracks for snowblowers are commonly used.

Why tracked and not wheeled?

jiokl
01-20-2014, 12:37 AM
Thank you I will check those out and see what I can find. As for why I'm picking tracked and not wheeled is purely just because I like the look better. Is there really any differences in the two? Besides the obvious of course, but is there going to be any real limitations of using a track system rather then wheeled?

tician
01-20-2014, 03:26 AM
Both tracked and wheeled skid steer require a bit more torque to turn compared to two wheel differential drive. It is due to the extra surface area in contact with the ground that must be dragged sideways while turning. It is why tracks not very nice to use on grass because they rip it up anytime they are not traveling straight ahead.

It is possible to use steered tracks (some multi-segment snowcats and similar vehicles), but that requires more than one pair of tracks to decrease the length of the contact area of each individual track (shorter the track, the less area must be dragged sideways when turning).

This post was written a couple hours ago, but got distracted by a wiki-walk and youtube.