Double Layer Detection of Sheet Metal and Body Parts by Laser Distance Sensors Triangulation

In the automotive industry, sheet metal parts are taken from a stock by a robot gripper and fed to the welding robot. Several sheets can stick together due to adherent oil, wedging of the sheets or magnetic charge. To ensure that only one sheet is gripped per assembly process, two laser distance sensors triangulation are mounted at opposite positions. The sensors measure the distance to the sheet and then calculate the sheet thickness via a difference calculation. If this result is greater than that of an individual sheet, a signal is output.