Workpiece edge detection using plasma arc cutting system
View Patent ↗Systems and methods can be provided to use an automated cutting system to identify an edge or multiple edges of a workpiece. An automated cutting system receives trace data for a test path to be traced over a workpiece. The automated cutting system includes a torch from which gas is flowed. The torch is controlled in accordance with the trace data to trace the test path over the workpiece. A set of back pressure values are obtained by monitoring a back pressure of the gas during the tracing of the path. The back pressure values are mapped to a set of coordinates. An edge of the workpiece is identified using the set of back pressure values and the set of coordinates.
1. A computer program product, tangibly embodied in a non-transitory, computer-readable storage device, for identifying an edge of a workpiece, the computer program product including instructions operable to cause an automated cutting system to:
receive trace data for a test path to be traced over the workpiece;
flow a gas from a torch of the automated cutting system;
control the torch in accordance with the trace data to trace the test path over the workpiece;
obtain a set of back pressure values by monitoring a back pressure of the gas during the tracing of the path;
map the set of back pressure values to a set of coordinates; and
identify an edge of the workpiece using the set of back pressure values and the set of coordinates.
2. The computer program product of claim 1 wherein the gas comprises air.
3. The computer program product of claim 1 wherein the gas is expelled from a shield line.
4. The computer program product of claim 3 wherein the gas comprises air.
5. The computer program product of claim 1 wherein the back pressure is monitored by a pressure sensor on a plasma gas supply line.
6. The computer program product of claim 1 wherein the set of back pressure values and the set of coordinates are used to identify a plurality of edges.
7. The computer program product of claim 6 wherein the plurality of edges of the workpiece and a scrap clearance are used to determine a working area of the workpiece.
8. The computer program product of claim 7 wherein the scrap clearance is less than or equal to 2 inches.
9. A computer-implemented method for finding an edge of a workpiece with an automated cutting system, comprising:
providing a computing device with trace data for a test path to be traced over the workpiece;
flowing a gas from a torch of the automated cutting system;
controlling the torch in accordance with the trace data to trace the test path over the workpiece;
wherein the controlling includes measuring a back pressure of the flowing gas during the tracing;
converting the measured back pressure into a set of back pressure values;
mapping the set of back pressure values to a set of coordinates; and
analyzing the set of back pressure values and the set of coordinates to obtain a subset of coordinates representing an edge of the workpiece.
10. The method of claim 9 wherein the gas comprises air.
11. The method of claim 9 wherein the gas is expelled from a shield line.
12. The method of claim 11 wherein the gas comprises air.
13. The method of claim 9 wherein the back pressure is measured by a pressure sensor on a plasma gas supply line.
14. The method of claim 9 wherein the computing device comprises a deterministic network.
15. The method of claim 14 wherein the deterministic network comprises an EtherCAT interface.
16. The method of claim 9 wherein the set of back pressure values and the set of coordinates are used to identify a plurality of edges.
17. The method of claim 16 further comprising defining a working area of the workpiece with reference to the plurality of edges and a scrap clearance.
18. The method of claim 17 wherein the scrap clearance is less than or equal to 2 inches.