The device uses a pair of solenoids to control a hammer that hits the roll surface and the deceleration is recorded. The hammer can achieve fifty hits per second and so moving the device across the surface of a roll does not take long. The data is stored and displayed and can also be transferred to other suitable WLAN devices.
I have not tried out this device for myself but needless to say watching the demonstration video does make it appear easy. Judge for yourselves by watching the demonstration for yourself at http://www.youtube.com/watch?v=Ix9BP9Gcdzw
I have seen vacuum coaters who pay no attention to the problems of incoming roll hardness variations and others who do check the roll hardness but do so by manually bouncing a stick on the surface. Neither of these provides good quality information that can be stored and travel with the roll from process to process which can be useful if there are problems that require troubleshooting. The data may also be a useful demonstration to customers showing that good quality rolls have been used for the product they are buying.