UK-based Oxford Sensor Technology (OST) based in Abingdon, Oxfordshire (UK), has been awarded three major orders to supply vision sensors to enable automated vehicle glazing for one American and two European automotive plants.
The order follows a world first at Ford Dagenham (UK) undertaken with Cimac, Stanford Le Hope, Essex, where OST sensors enabled windscreens to be fitted whilst the vehicle was moving along the production line.
The OST Specular Reflection Sensor (SRS) uses light reflected from curved surfaces to precisely locate features on the car body. This information then guides the glass insertion robots to the correct apertures, allowing positioning of glass within a fraction of a millimetre.
Most commercially available optical measuring devices work on the principle of detecting light scattered from the work piece. While it works with some surface finishes, using this conventional method on highly reflective or specular materials makes it extremely difficult to obtain a reliable measurement. This is particularly true for surfaces such as glass and other transparent materials, polished metals and black gloss paint finishes.
The SRS range of sensors was developed by OST specifically to overcome the problem of imaging these highly reflective and specular surfaces by exploiting their otherwise difficult characteristics to the overall benefit of the sensing system.
Optically, rounded features on any specular surface act as cylindrical mirrors which image the LED light sources projected by the sensor. These images are then detected by two integral cameras in the sensor which sends the measured and pre-processed data to a control PC via the CAN Bus. The information is then used to guide the glass insertion robots to within a fraction of a millimetre.