Adding friction material to timing belts

[Mr V]

Years ago there was a track style robot in the PNW that used timing belts as the tracks. They were custom made timing belts that had a urethane backing on it. They were extremely grippy. They were like a 2" wide belt and if I remember right they weren't all that expensive considering their size and that they were custom built. I'd check with Gates and see if you can get a pre-done solution.