Where to Find Treads

It appears that treads for robots come in two sizes: too large and too small. I am planing to build a robot that will be around 40-50 cm long and I have been looking for a suitable solution for several years. The rubber treads that can be bought are either for small excavators and are much too large even if you were to use the smallest available size. Another alternative that I came up with was to use treads from a snowmobile, but these too are a bit on the heavy side although I know of at least one project that has used them for a 400 pound robot (movie here). Other alternative methods of designing treads are described at the R/C Combat site.

Since I had something a little more lightweight in mind, I have been looking around for an alternative solution. My first stream of hope came when I saw a threaded model sold by Conrad which was about the right size and seemed to be very robust. Living in Sweden made ordering extremely complicated. It used to work well, but now that they have a Swedish distributer everything seem to be a mess. After too many frustrations to mention, I eventually received a package, which to my surprise contained a completely different model. Apparently, the one I had ordered was discontinued and they thought I would be just as happy with some other random model. Needless to say, I will never buy anything from them again.

It may have been possible to start with something like the Traxter platform, but it would have been a little too small for my purposes. Fortunately there are several alternatives. Another possibility would be to use the sprocket-driven conveyor belts that are available from McMaster-Carr. These have been used in several tank models and seem to have all the desired properties. The only problem may be the cost and the fact that they lack a rubber surface that may be needed for sufficient traction. I was almost about to order these when I came across the track system manufactured by Lynxmotion. These are very similar to a conveyor belt, but contain a rubber pattern on one side. They come in two widths and I ordered the larger size which is 75 mm wide. They can be put together to any length. It remains to be seen how well they work in practice.