[MrForbes]

make the belly pan heavy, and you're robot won't be so likely to fall over....

But if you're going to put electronics directly on it, then making it insulating is also a good idea.

We've used 1/16" aluminum and 1/8" plywood to good effect in different years. Aluminum is easy to rivet to the frame (assuming the frame is aluminum or fiberglass or similar), and wood is easy to staple/glue to a wood frame.

I'd still like to be able to use 1/4" steel plate for the bellypan....it's a life goal....