Modular multi-axis motion control and driving system and method thereof

• US 7,194,321 B2
• Filed: 10/29/2004
• Issued: 03/20/2007
• Est. Priority Date: 10/29/2004
• Status: Expired due to Fees

• Current Assignee: Dynacity Technology Limited
• Original Assignee: Dynacity Technology Limited
• Inventors: Sun, Dong, Shao, Xianyin
• Primary Examiner(s): Knight; Anthony
• Assistant Examiner(s): Chang; Sunray
• Application Number:
  US10/975,404
• Publication Number:
  US 20060100723A1
• Time in Patent Office: 872 Days
• Field of Search: 700/61, 700/2, 700/20, 370/419, 318/254, 318/34
• US Class Current: 318/400.01
• CPC Class Codes: G05B 19/4141 characterised by a controller or microprocessor per axis
• CPC Class Codes: G05B 2219/34024 Fpga fieldprogrammable gate arrays
• CPC Class Codes: G05B 2219/34047 Dsp digital signal processor
• CPC Class Codes: G05B 2219/34157 Synchronize interpolation of different axis boards, simultaneous start
• CPC Class Codes: G05B 2219/34466 Bad circuits, watchdog, alarm, indication
• CPC Class Codes: G05B 2219/36386 Bootstrap loader
• CPC Class Codes: G05B 2219/50216 Synchronize speed and position of several axis, spindles

Abstract

A modular multi-axis motion control and driving system includes a control board having a DSP and Flash ROM; a plurality of driver boards connected to the control board though a bus, each board including a FPGA device and a plurality of MOSFET power amplifiers; a computer, connected to the control board provides a graphic user interface through which motor setting, current and position control loop tuning and diagnostic may be performed. A DSP program, system parameters and FPGA configuration file are stored in the Flash ROM. At startup the DSP automatically executes loader firmware transferring the DSP program from the Flash ROM to the DSP. The DSP reads the FPGA configuration file and configures the FPGA in each driver board simultaneously. The control program then loops to perform system diagnose, network service and check command queue, while the current and position controls are implemented in an interrupt service.

Claims

1. A modular multi-axis motion control and driving system comprising:

a control board comprising a DSP and Flash ROM connected to each other, for performing position control, velocity control and current control of said system;

a plurality of driver boards, connected to the control board though a bus, each of which comprise an FPGA device and a plurality of MOSFET power amplifiers for driving a plurality of servo motors;

a host computer, connected to said control board, the host computer configured to provide a graphic user interface, through which motor setting, current and position loop tuning and diagnostic can be performed;

wherein, a DSP control program, system parameters and an FPGA configuration file are stored in said Flash ROM;

wherein the DSP is configured to automatically execute loader firmware to transfer the control program from said Flash ROM to a memory of the DSP for execution;

wherein the DSP is further configured to read the FPGA configuration file from the Flash ROM and configure each FPGA in the plurality of driver boards simultaneously;

wherein the control program is configured to run in a circulation loop performing system diagnose, network service and check command queue, while the current and position controls are implemented in an interrupt service routine; and

wherein each driver board further comprises a I/O connector for providing digital I/O, analog input, differential I/O connection for the FPGA device, a differential receiver/transmitter through which the differential I/O signal is connected to the FPGA device, an A/D converter for converting the analog input to digital signal, a connect port provided for connecting to external brake coils; and

wherein each of said plurality of I/O connectors comprises an input/output port including 4 differential outputs, 2 differential inputs, 2 optically-isolated inputs, 4 optically-isolated outputs and 2 individual analog inputs with 12 bit true differential resolution.

2. A system as claimed in claim 1, wherein said control board further comprises at least one of a RS232 and a RS485 connector configured to connect, via operation of a switch, said computer to said control board.

3. A system as claimed in claim 2:

wherein an RS232 interface protocol provides node to node communication between the controller and the host computer;

wherein an RS485 interface protocol provides multi-node communication; and

wherein the system is configured to allow up to 32 controllers to be connected to the RS485 network and communicate between each other and!or the host computer.

4. A system as claimed in claim 1, wherein said FPGA device implements PWM generator, decoder/hall logic circuit, digital I/O, counters and some other glue logics.

5. A system as claimed in claimed in claim 1, wherein each of said plurality of MOSFET power amplifiers further comprises a 3-phase bridge driver, a inverter connected to and droved by the 3-phase bridge driver for provides power for said servo motors.

6. A system as claimed in claim 5, wherein said driver board further comprising current-sensing resistors for current sensing in a motor'"'"'s electronic power stage, said current-sensing resistors are in series with the ground return of the inverter, the analog signals from the sensing resistors are converted to digital signals by said A/D converter, and then are sent to the DSP of the control board via said bus.

7. A system as claimed in claim 1:

wherein the plurality of driver boards comprises 1–

3 driver boards;

wherein each driver board is configurable, based upon a user'"'"'s requirement, to drive a plurality of servo motors; and

wherein said system uses 2, 4, or 6 axes.

8. A system as claimed in claim 1, wherein each of said plurality of driver boards connects 2 servo motors of a type selected from a type of motors consisting of DC brushless motors, DC brushed motors, and AC servo motors, the graphic user interface operable to select the type of motor.