Development of a Flexible Protective System for Press-Brakes Using Vision Part I: Algorithm

All existing safety systems for press-brakes have fixed protective volume. These protective systems do not consider the instantaneous motion of the worker´s hands. This paper presents the development of a flexible protective system, taking this feature into account. The space before the machine is divided into three zones: initial interdiction, flexible interdiction and inspection. The instantaneous motion of the worker´s hands is tracked using two cameras. The innovative solution consists of generating a flexible interdiction zone whose dimensions and shape depend on the instantaneous velocity of the inspected point and of the initial interdiction zone. The interference between the inspected point and the flexible interdiction zone is verified using the modified transversability vector. The system generates a decision in real-time. The reliability of the method is validated through numerous experiments