attaching anti slip mat

Can we use double stick tape to attach anti slip mat to the tank tread fins? If not… what have others used?

In the Past I had a roller that had anti-slip. I tried various ways (tape, ties, screws, etc.) and by the end if the season found that zipties with a plastic washer on it works best!

can we use double stick tape… is it competition legal

No,

R15 - B
Welding, soldering, brazing, gluing, or attaching in any way that is not provided within the VEX
Robotics Design System will NOT be allowed.

but you could use …

would work the same in theory, but i have used screws in the past and they work well, so do zip ties and rubber bands

Yep, zipties are the best way