position of the wiper motor 130 is directly proportional to an angular position of the wiper arm 120 such an arrangement is called a u201c direct drive u201d and is suited to the invention without restrictions the oscillating operation of the wiper arm 120 of fig1 is achieved by controlling the rotational direction of the wiper motor 130 a speed control of said wiper motor 130 ensures a harmonic speed progression of the wiper arm 130 wherein the speed progression at least approximates the substantially sinusoidal speed progression which is produced by the use of the crank mechanism 125 in fig1 the reduction gear unit 160 can comprise a spur gear unit planetary gear set worm gear pair or belt drive or any other desired gearing which produces a scaling factor of the rotational motion of the wiper motor 130 that is independent of the angle of rotation in the rotational motion of the wiper arm 120 in other embodiments of the wiper system 100 the rain sensor 145 the speed sensor 150 and or the position sensor 155 can also be omitted in addition the drive motor 130 can also act on the wiper arm 120 via a rotary gear unit for example a spur gear unit or a planetary gear set whereby the crank mechanism 125 is omitted such a wiper system is also referred to as a.