http://www.forbes.com/sites/william...nic-envelopes-may-wipe-out-windshield-wipers/
Speculation is on some form of ultrasonics - which your dog may not like. At low vehicle speeds the phase is adjusted so that water moves down the screen assisted by its weight. At higher speeds it switches the other way to work with airflow.
Speculation is on some form of ultrasonics - which your dog may not like. At low vehicle speeds the phase is adjusted so that water moves down the screen assisted by its weight. At higher speeds it switches the other way to work with airflow.