In pictures: D-Day inventions

Another of "Hobart's funnies" was the Bobbin carpet layer, designed to overcome the problem of beach sand or loose shingle that could not support the weight of armoured vehicles or heavy guns.

The reinforced matting was laid out in front of the tank and then stayed in place for other vehicles that followed behind.

Like all the "funnies", the Bobbin was tested in secret dummy landings in remote parts of Britain but the first test in combat was D-Day itself.