Double stick velcro work great!

Thanks for the idea to use command strips. I am going to go try it on my hardwood floor.

Staple two mouse pads together with right sides together. The rough back sides will hold the pedal and grip the floor or carpet. Works for me.

I use a rubber gripper that was intended to be used to help open jars!

I second New knee's suggestion. I bought 2 el-cheapo mouse pads from the dollar store and glued them right sides together. Works on both my carpet and hardwood floors.

Try putting a strip of sticky backed velcro (the stiff hook side) on the bottom of the foot pedals. It will grip the carpet and keep the foot from moving.

I put the foot pedal around one of hubby's holey socks and it doesnt move on my carpet.

I have a brick I put behind mine. The foot control never moves. A big rock would work, too. DH and sons have learned to not ask why I have a brick in my sewing room. Tee-Hee!

I used the rubbery stuff you put under carpet (cut to shape of pedal)

I tried that and it didn't work! Waiting for more suggestions....