Quality Control of Windscreen Wipers Adapted to Driver's Visual Perception

The quality of windscreen wipers has to be measured objectively in the stages of development and manufacturing and after a certain period of operation as well. Starting from the insufficient and mostly subjective methods being available for windscreen wipers an objective measurement procedure was developed by which the driver's visual performance is taken into consideration. Under simulated night-time driving conditions the intensity of the stray light produced by the water left behind is measured as a function of time and of the local coordinates. In practice a prototype of a computer-controlled measurement unit showed a better evaluation of the transient part of the stray light (veil) compared with subjective judgement.