System and method for machining data management

• US 20040176926A1
• Filed: 03/06/2003
• Published: 09/09/2004
• Est. Priority Date: 03/06/2003
• Status: Active Grant

• Current Assignee: Ford Motor Company
• Original Assignee: Ford Motor Company
• Inventors: Simpson, Roderick Alexander, Kaufman, Ingrid Margrit, Edie, Paul Charles
• Granted Patent: US 6,845,340 B2
• Time in Patent Office: Days
• US Class Current: 702/179
• CPC Class Codes: B23Q 17/0971 by measuring mechanical vibrations of parts of the machine arrangements for measuring vibrations B23Q17/12
• CPC Class Codes: G05B 2219/35528 Create machining conditions database by analyzing actual machining nc program

Abstract

A system and method for machining data management is provided. Vibration and operation data are gathered from a machine tool and sent to a processing unit. The processing unit defines operation-specific vibration profiles, and generates an operation-specific data line for each profile. The data lines are stored in a memory for later retrieval. An output device is used to retrieve the data lines and plot them over a time domain to create an operation-specific data matrix useful in manufacturing operations analysis.

Claims

1. A method for managing machine tool data using a data matrix, the machine tool having a plurality of tools for performing machining operations on a workpiece, at least one sensor operatively connected to the machine tool for sensing a machine operation parameter and outputting signals related to the sensed parameter, and a controller configured to output signals related to the machining operations, the method comprising:

performing a first set of machining operations on the workpiece;

processing data from signals output from the at least one sensor and from the controller to define operation-specific data profiles; and

applying an algorithm to at least some of the operation-specific data profiles to generate an operation-specific data line for each of the at least some operation-specific data profiles, thereby facilitating generation of an operation-specific data matrix, the operation-specific data lines having a time dependent length and representing a statistical value of the sensed parameter.

2. The method of claim 1, further comprising:

performing the first set of machining operations on at least one additional workpiece;

generating operation-specific data lines for the at least one additional workpiece; and

combining operation-specific data lines by operation for the first workpiece and the at least one additional workpiece, thereby facilitating generation of a single, operation-specific data matrix for all of the machined workpieces.

3. The method of claim 1, further comprising defining at least one fault condition for each of the operations performed on the workpiece.

4. The method of claim 3, wherein defining a fault condition comprises:

operating the machine tool in a learning mode, the learning mode including operating the machine tool under idling conditions without removing material from a workpiece, operating the machine tool under controlled machining conditions for a first predetermined number of cycles, and operating the machine tool under machining conditions for a second predetermined number of cycles, larger than the first predetermined number of cycles;

processing data from signals output from the at least one sensor and from the controller during the learning mode operation to generate learning mode operation-specific data profiles;

applying a learning mode algorithm to at least some of the learning mode data profiles to generate an operation-specific data line for each of the at least some learning mode data profiles;

discarding a data line if its value is outside a predetermined limit; and

defining a fault condition based on the data lines not discarded.

5. The method of claim 1, further comprising plotting a single, operation-specific data point for each operation-specific data line, thereby creating an operation-specific trend line.

6. The method of claim 1, further comprising generating operation-specific data lines for different sets of machining operations performed on the machine tool, thereby facilitating generation of an operation-specific data matrix for each set of machining operations performed.

7. The method of claim 6, further comprising:

machining a production workpiece on the machine tool;

generating operation-specific data lines for the production workpiece; and

comparing the production workpiece data lines with previously defined data lines, thereby facilitating evaluation of the production workpiece machining.

8. The method of claim 1, wherein the at least one sensor is configured to sense at least one of vibrations, current, temperature, torque and speed.

9. The method of claim 1, wherein the operation-specific data lines include at least one of tool-specific data lines and idle data lines.

10. A method for managing machine tool data using a data matrix, the machine tool having a plurality of tools for performing machining operations on a workpiece, at least one sensor operatively connected to the machine tool for sensing a machine operation parameter and outputting signals related to the sensed parameter, and a controller configured to output signals related to the machining operations, the method comprising:

sensing a machine operation parameter from the machine tool for a first set of machining operations;

storing data related to the sensed parameter;

storing data from signals output from the controller;

associating the data from the sensor with the data from the controller, thereby defining operation-specific data profiles;

applying an algorithm to at least some of the operation-specific data profiles to generate an operation-specific data line for each of the at least some operation-specific data profiles, the operation-specific data lines having a time dependent length and representing a statistical value of the sensed parameter; and

storing the operation-specific data lines, thereby facilitating subsequent retrieval.

11. The method of claim 10, further comprising:

retrieving the operation-specific data lines; and

plotting the data lines to create an operation-specific data matrix.

12. The method of claim 10, wherein each of the data lines is a function of a normalized vibration amplitude and time.

13. The method of claim 10, further comprising:

defining a fault condition characterized by a single machine tool problem, the machine tool problem including one of a machining problem and an idling problem; and

defining an alarm condition characterized by a predetermined number of fault conditions.

14. The method of claim 13, wherein defining a fault condition comprises:

operating the machine tool in a learning mode, the learning mode including operating the machine tool under idling conditions without removing material from a workpiece, operating the machine tool under controlled machining conditions for a first predetermined number of cycles, and operating the machine tool under machining conditions for a second predetermined number of cycles, larger than the first predetermined number of cycles;

processing data from signals output from the at least one sensor and from the controller during the learning mode operation to generate learning mode operation-specific data profiles;

applying a learning mode algorithm to at least some of the learning mode data profiles to generate an operation-specific data line for each of the at least some learning mode data profiles;

discarding a data line if its value is outside a predetermined limit; and

defining a fault condition based on the data lines not discarded.

15. The method of claim 10, further comprising:

performing the first set of machining operations on a plurality of workpieces;

generating operation-specific data lines for each of the workpieces machined; and

combining operation-specific data lines by operation for each of the machined workpieces, thereby facilitating generation of a single, operation-specific data matrix for all of the machined workpieces.

16. The method of claim 15, further comprising:

machining a production workpiece on the machine tool;

generating operation-specific data lines for the production workpiece; and

comparing the production workpiece data lines with previously defined data lines, thereby facilitating evaluation of the production workpiece machining.

17. A data management system for a machine tool having a plurality of tools for performing machining operations on a workpiece, and a controller configured to output signals related to the machining operations, the data management system comprising:

a sensor configured to be operatively connected to the machine tool for sensing a machine operation parameter and outputting signals related to the sensed parameter;

a processor operatively associated with the sensor and the controller, and configured to associate data from the signals output from the sensor and from the controller to generate operation-specific data profiles, the processor being further configured to apply an algorithm to at least some of the operation-specific data profiles, thereby generating an operation-specific data line for each of the at least some operation-specific data profiles; and

a memory operatively associated with the sensor, the controller, and the processor, and configured to store information including the operation-specific data lines, thereby facilitating subsequent retrieval of the stored information.

18. The data management system of claim 17, wherein the operation-specific data lines include a time dependent length and represent a statistical value of the sensed parameter.

19. The data management system of claim 17, wherein the operation-specific data profiles include tool-specific data profiles and idling data profiles.

20. The data management system of claim 19, wherein the processor is further configured with an alarm condition defined as a predetermined number of fault conditions in a predetermined number of machine cycles.

21. The data management system of claim 17, further comprising an output device configured to receive the operation-specific data lines from the memory, and to plot the data points over a time domain, thereby generating an operation-specific data matrix.

22. The data management system of claim 17, wherein the sensor is further configured to sense at least one of vibrations, current, temperature, torque and speed.