Cats’ whiskers have a function similar to curb feelers which were common on cars in the 1950’s. These were springy rods that stuck out a short distance from the lower parts of the cars, and would make a rubbing noise when they touched a curb. When a cat pokes its head into a small tunnel or opening in the bushes, the whiskers are used to gauge the dimensions. If the opening doesn’t rub the whiskers, the cat’s body will fit through.
