LINE TRACKING DATA OVER ETHERNET

• US 20100063625A1
• Filed: 09/05/2008
• Published: 03/11/2010
• Est. Priority Date: 09/05/2008
• Status: Active Grant

• Current Assignee: Fanuc Robotics America Incorporated (Fanuc Corporation)
• Original Assignee: Fanuc Robotics America Incorporated (Fanuc Corporation)
• Inventors: Huber, Jim, Clifford, Scott J., Krause, Kenneth W., Graca, Randy, Wong, Ho Cheung
• Granted Patent: US 9,046,890 B2
• Time in Patent Office: Days
• US Class Current: 700/245
• CPC Class Codes: G05B 19/4182 manipulators and conveyor only
• CPC Class Codes: G05B 2219/31432 Keep track of conveyed workpiece, batch, tool, conditions of stations, cells
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A robot control system includes a line tracking encoder that measures a reference position of a conveyor line and transmits a tracking signal representing tracking data including the reference position of the conveyor line. A master controller is in communication with the encoder to receive the tracking signal, process the tracking data represented by the tracking signal, and generate a data packet in response to processing of the tracking data. A slave controller is in communication with the master controller and at least one robot for receiving the data packet and controlling the movement of the at least one robot in response to the data packet. A communications network directly interconnects the master controller and the slave controller and transmits the data packet from the master controller to the slave controller.

Claims

1. A control system, comprising:

a line tracking encoder adapted to measure a reference position of a conveyor line and transmit a tracking signal representing tracking data including the reference position of the conveyor line;

a master controller in communication with said encoder, said master controller adapted to receive said tracking signal, process said tracking data represented by said tracking signal, and generate a data packet in response to processing of said tracking data;

a slave controller in communication with said master controller and in electrical communication with at least one robot, said slave controller adapted to receive said data packet and control movement of said at least one robot in response to said data packet; and

a communications network directly interconnecting said master controller and said slave controller, wherein said communications network is adapted to transmit said data packet from said master controller to said slave controller.

2. The control system according to claim 1 wherein processing of said tracking data comprises the steps of:

determining the reference position of the conveyor line;

determining a tick time value for the reference position; and

determining a velocity value of the conveyor line.

3. The control system according to claim 2 wherein said master controller is adapted to predict a future position of the conveyor line in response to processing of said tracking data.

4. The control system according to claim 3 wherein said master controller is adapted to compare the predicted future position of the conveyor line with the reference position within a pre-determined tolerance range.

5. The control system according to claim 4 wherein said data packet is transmitted only when the reference position value is not in within the tolerance range of the predicted future position calculated by said master controller.

6. The control system according to claim 1 wherein said master controller includes a synchronization system to time tag said tracking data.

7. The control system according to claim 1 wherein said data packet includes at least one of the reference position of the conveyor line, a tick time value for the reference position of the conveyor line, and a velocity value of the conveyor line.

8. The control system according to claim 1 wherein said slave controller is adapted to predict a position of the conveyor line in response to said data packet.

9. The control system according to claim 1 wherein said communications network is an Ethernet network.

10. A method for controlling movements of a plurality of robots, the method comprising the steps of:

measuring a reference position of a conveyor line;

transmitting a tracking signal representing tracking data including the reference position of the conveyor line;

processing the tracking data represented by the tracking signal;

generating a data packet in response to the processing of the tracking data;

transmitting the data packet over a communications network;

processing the data packet to predict a future position of the conveyor line; and

controlling a movement of at least one robot in response to the processing of the data packet.

11. The method according to claim 10 wherein the processing of the tracking data comprises the steps of:

determining a tick time value for the reference position of the conveyor line; and

determining a velocity value of the conveyor line.

12. The method according to claim 11 wherein the data packet includes at least one of the reference position of the conveyor line, the tick time value for the reference position of the conveyor line, and the velocity value of the conveyor line.

13. The method according to claim 10 wherein the communications network is an Ethernet network.

14. The method according to claim 10 wherein the processing of the tracking data comprises the steps of:

predicting a future position of the conveyer line; and

comparing the reference position to the predicted future position of the conveyor line.

15. A method for controlling movements of a plurality of robots, the method comprising the steps of:

providing a control system including,

a line tracking encoder adapted to measure a reference position of a conveyor line and transmit a tracking signal representing tracking data including the reference position of the conveyor line, and

a master controller in communication with the encoder, the master controller adapted to receive the tracking signal, process the tracking data represented by the tracking signal, and generate a data packet in response to processing of the tracking data;

providing a slave controller in communication with the master controller and in electrical communication with at least one robot; and

a communications network directly interconnecting the master controller and the slave controller;

transmitting the data packet over the communications network to the slave controller; and

controlling a movement of the at least one robot in response to the data packet.

16. The method according to claim 15 wherein the processing of the tracking data comprises the steps of:

determining the reference position of the conveyor line;

determining a tick time value for the reference position; and

determining a velocity value of the conveyor line.

17. The control system according to claim 15 wherein the master controller includes a synchronization system to time tag the tracking data.

18. The method according to claim 15 wherein the data packet includes at least one of the reference position of the conveyor line, a tick time value for the reference position of the conveyor line, and a velocity value of the conveyor line.

19. The method according to claim 15 wherein the slave controller is adapted to predict a future position of the conveyor line in response to the data packet.

20. The method according to claim 15 wherein the communications network is an Ethernet network.