Siemens Aktiengesellschaft

Jörg Handeck

Steffen Mihatsch

Steffen Schmauder

Carsten Hamm

Jochen Bretschneider

Tomas Sauer

Curd Weber

Martin Sturm

A numerical controller uses specifications to control position-controlled axes of a production machine and determines a current group of position setpoint values and groups of position setpoint values expected for a forecast horizon. The numerical controller checks for the risk of a collision between at least one element moved by the position-controlled axes and at least one other element. The numerical controller carries out the same check for the expected groups. If there is no risk of collision, it stores the expected groups in a braking path memory and uses the current group. If there is the risk of a collision, it changes the axes along a path to a standstill defined by the braking path memory and braking is effected along a path which has been previously checked for the risk of a collision and for which no risk of a collision has been detected.

Stopping a production machine on a collision-free path

Elements of a machine are moved relative to one another along several axes. A monitoring device receives groups of position values of the axes which specify the relative position of the elements to one another. The surfaces and/or volumes of the elements taking up working space are determined therefrom. The monitoring device checks whether a collision risk between the elements exists. The monitoring device models at least parts of the surfaces of the elements with two-dimensional splines defined by nodes and checkpoints. The monitoring device further determines from the checkpoints of the splines for sections envelopes which envelop respective element in the respective section, and uses the respective envelope as a surface that is taken up by the respective element in the respective section. Boundary lines of faces of the envelopes are straight connecting lines of the checkpoints.

Collision testing on the basis of high-quality geometry

Movable elements of a machine are moved by a control device of the machine by controlling drives of the machine. To monitor the movement of the movable elements for collision with each other or with a stationary element, two monitoring devices check, independently from each other, using a computer program, whether there is a risk of collision in the working space. Depending on whether the monitoring devices detect a risk of collision or not, they intervene, independently from each other, in a corrective manner, in the control of the drives or not, and/or independently emit an alarm message or not. The two computer programs are designed in a diverse manner. The two monitoring devices differ from one another. One monitoring device is identical to the control device, while the other monitoring device is embodied as an industrial PC with a data link to the control device.

Redundant, diverse collision monitoring

Growing community of inventors

Erlangen, Germany

Jörg Handeck