Multi-core processing machine tool control system

• US 10,386,817 B1
• Filed: 09/12/2016
• Issued: 08/20/2019
• Est. Priority Date: 09/11/2015
• Status: Active Grant

• Current Assignee: HAAS Automation Incorporated
• Original Assignee: HAAS Automation Incorporated
• Inventors: Lototsky, Sergey, Gradinarski, Radik
• Primary Examiner(s): Ali, Mohammad
• Assistant Examiner(s): Booker, Kelvin
• Application Number:
  US15/263,251
• Time in Patent Office: 1,072 Days
• CPC Class Codes: G05B 19/18 Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form G05B19/418 takes precedence
• CPC Class Codes: G05B 19/402 characterised by control arrangements for positioning, e.g. centring a tool relative to a hole in the workpiece, additional detection means to correct position G05B19/19 takes precedence
• CPC Class Codes: G05B 19/40938 Tool management
• CPC Class Codes: G05B 19/4144 characterised by using multiplexing for control system
• CPC Class Codes: G05B 19/4148 characterised by using several processors for different functions, distributed (real-time) systems G05B19/4141 takes precedence
• CPC Class Codes: G05B 2219/33338 DNC distributed, decentralised nc, concurrent, multiprocessing
• CPC Class Codes: G05B 2219/34045 Timer
• CPC Class Codes: G05B 2219/34258 Real time system, qnx, works together with non real time system, windows nt
• CPC Class Codes: G05B 2219/37618 Observe, monitor position, posture of tool

Abstract

A machine tool control system may include a processing module and subsystem circuitry coupled to the processing module by a bus. The processing module may include memory circuitry and a multi-core processor. The multi-core processor may include a first set of processor cores assigned exclusively to perform real-time tasks for controlling motion relative to one or more axes by executing first instructions stored in the memory circuitry, a second set of processor cores assigned exclusively to perform non-real-time tasks by executing second instructions stored in the memory circuitry, and a timer circuit configured to generate a cycle signal at periodic intervals. The subsystem circuitry may be configured to obtain axis feedback data from one or more feedback encoders and axis control data from the first set of processor cores during each of the periodic intervals. The subsystem circuitry further may be configured to provide the obtained axis feedback data to the first set of processor cores and the axis control data to one or more axis drivers in response to the cycle signals generated by the timer circuit.

Claims

1. A machine tool control system, comprising:

a processing module including;

memory circuitry;

a multi-core processor including;

a first set of processor cores assigned exclusively to perform real-time tasks for controlling motion relative to one or more axes by executing first instructions stored in the memory circuitry;

a second set of processor cores assigned exclusively to perform non-real-time tasks by executing second instructions stored in the memory circuitry; and

a timer circuit configured to generate a cycle signal at periodic intervals; and

subsystem circuitry coupled to the processing module by a bus,

wherein the subsystem circuitry is configured to obtain axis feedback data from one or more feedback encoders and axis control data from the first set of processor cores during each of the periodic intervals,

wherein the subsystem circuitry is further configured to provide the obtained axis feedback data to the first set of processor cores and the axis control data to one or more axis drivers simultaneously at the cycle signals generated by the timer circuit,

wherein the first set of processor cores comprises;

a first processor core assigned exclusively to perform a motion control loop for each of the one or more axes; and

a second processor core assigned exclusively to perform a main control loon for each of the one or more axes,

wherein the main control loop performed by the second processor core generates a trajectory point for motion relative to a respective axis of the one or more axes based on a program, and

wherein the motion control loop performed by the first processor core generates the axis control data for a respective axis driver corresponding to the respective axis based on the generated trajectory point and the axis feedback data.

2. The machine tool control system of claim 1, wherein the processing module comprises a module interface configured to detachably connect the processing module to the bus.

3. The machine tool control system of claim 1, wherein each iteration of the motion control loop is performed during a single interval of the periodic intervals and each iteration of the main control loop is performed during a plurality of intervals of the periodic intervals.

4. The machine tool control system of claim 1, wherein the cycle signal generated by the timer circuit is communicated internally to the multi-core processor only with the first processor core.

5. The machine tool control system of claim 1, wherein the second set of processor cores comprises:

a third processor core assigned exclusively to execute an operating system for the machine tool control system; and

a fourth processor core assigned exclusively to generate a graphical user interface for display and manage data communication with the machine tool control system.

6. The machine tool control system of claim 5, further comprising an input/output interface configured to electrically couple a user interface to the machine tool control system, wherein the user interface comprises a display for displaying the graphical user interface generated by the fourth processor core and a user input system for receiving user input.

7. The machine tool control system of claim 1, wherein the memory circuitry comprises:

volatile memory; and

non-volatile memory storing the first and second instructions.

8. The machine tool control system of claim 1, further comprising:

a digital-to-analog converter corresponding to each of the one or more axis drivers; and

an axis driver interface configured to electrically couple the one or more axis drivers to the machine tool control system,

wherein the subsystem circuitry is configured to buffer the axis control data in the digital-to-analog converter for each of the one or more axis drivers during each of the periodic intervals, and

wherein the digital-to-analog converter for each of the one or more axis drivers is configured to convert and output the buffered axis control data to the one or more axis drivers via the axis driver interface at each of the cycle signals generated by the timer circuit.

9. The machine tool control system of claim 1, further comprising an axis feedback interface configured to electrically couple the one or more feedback encoders to the machine tool control system,

wherein the subsystem circuitry is configured to:

request the axis feedback data from the one or more feedback encoders during each of the periodic intervals via the axis feedback interface; and

receive the requested axis feedback data from the one or more feedback encoders during each of the periodic intervals via the axis feedback interface.

10. A method for controlling a machine tool, the method comprising:

generating a cycle signal at periodic intervals by a timer circuit;

in response to each cycle signal;

transferring current axis feedback data from subsystem circuitry to a processing module comprising a multi-core processor at the cycle signal;

initiating a real-time motion control loop in a first processor core of the multi-core processor in a processing module, wherein the real-time motion control loop generates next axis control data based on the current axis feedback data and a current trajectory point;

initiating a real-time main control loop in a second processor core of the multi-core Processor, wherein the real-time main control loop generates a next trajectory point;

requesting, by the subsystem circuitry, next axis feedback data from a feedback encoder corresponding to an axis of the machine tool; and

loading current axis control data into an axis driver corresponding to the axis; and

during each of the periodic intervals;

buffering the next axis control data generated by the motion control loop, wherein the next axis control data is loaded into the axis driver at a next cycle signal; and

receiving the next axis feedback data from the feedback encoder, wherein the next axis feedback data is transferred to the processing module at the next cycle signal by the subsystem circuitry.

11. The method of claim 10, wherein the main control loop is initiated by the motion control loop once every predetermined number of periodic intervals, and wherein each iteration of the motion control loop is performed during a single periodic interval of the periodic intervals and each iteration of the main control loop is performed during the predetermined number of periodic intervals.

12. The method of claim 11, wherein the next trajectory point is used by the motion control loop to generate next axis control data during a first periodic interval following the predetermined number of periodic intervals.

13. The method of claim 12, wherein the predetermined number of periodic intervals is four.

14. The method of claim 10, wherein requesting next axis feedback is delayed a predetermined period of time following each cycle signal.

15. The method of claim 10, wherein buffering the next axis control data comprises loading the next axis control data into a digital-to-analog converter, and

wherein loading the current axis control data comprises transferring converted axis control data from the digital-to-analog converter to the axis driver.