How to solve the problem of material moving when CNC router cut aluminium

When we cut aluminium by CNC router,we will easily have a problem like the video below.

Workpiece will move if we dont press it with our hand.So,now I want to share a solution.

You can see in the video below,this cnc router spindle is equiped with a pressure foot.

Then material sheet can be held automatically when cnc router cut it.

Pressure foot can be easily mounted on spindle by a screw.