POWER SOURCE MONITORING SYSTEM FOR AGVS AND METHOD

• US 20100138095A1
• Filed: 12/01/2008
• Published: 06/03/2010
• Est. Priority Date: 12/01/2008
• Status: Active Grant

• Current Assignee: Savant Automation, Inc.
• Original Assignee: Savant Automation, Inc.
• Inventors: Redmann, Jerry L. JR., Werner, Matthew L., Koff, Garry A.
• Granted Patent: US 7,890,228 B2
• Time in Patent Office: Days
• US Class Current: 701/24
• CPC Class Codes: B60L 2260/32 Auto pilot mode
• CPC Class Codes: B60L 58/12 responding to state of charge [SoC]
• CPC Class Codes: G05D 1/0217 in accordance with energy consumption, time reduction or distance reduction criteria
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

An automatic guided vehicle (AGV) and method has at least one AGV with a drive assembly, a rechargeable power source on-board the AGV configured to supply power to the drive assembly, and a controller on-board the AGV. The controller on-board the AGV is configured to substantially continuously monitor at least two conditions including an operating condition of the AGV, a state of charge of the power source, and an electrical power supplied for recharging the rechargeable power source, wherein the controller determines when the rechargeable power source of the AGV is to be recharged, and controls a recharging process of the power source based upon at least one of the monitored conditions.

Claims

1. In an automatic guided vehicle (AGV) system for automatically transporting loads along a predetermined path, the improvement comprising:

a stationary master controller;

at least one stationary system power source; and

a plurality of self-propelled AGVs, wherein at least one of said AGVs comprises;

a drive assembly;

a rechargeable power source on-board said AGV, and configured to supply power to said drive assembly for moving said AGV along the predetermined path, wherein said rechargeable power source is adapted to be selectively electrically connected to said system power source, which supplies an electrical power to recharge said rechargeable power source; and

a controller on-board said AGV, and configured to determine when said rechargeable power source of said AGV is ot be recharged, control a recharging process of said rechargeable power source independent of receiving information from said master controller, communicate with said master controller, and substantially continuously monitor at least two conditions comprising;

an operating condition of said AGV; and

a state of charge of said rechargeable power source;

whereby when said rechargeable power source is electrically connected to said system power source, said controller dynamically determines when said rechargeable power source of said AGV is to be recharged, controls a recharging process of said rechargeable power source independent of receiving information from said master controller, and communicates at least one of said monitored conditions to said master controller.

3. The AGV system of claim 1, wherein said controller determines when said rechargeable power source of said AGV is to be equalized.

4. The AGV system of claim 1, wherein said controller determines when said rechargeable power source is to be recharged to a state of charge above a threshold value.

5. The AGV system of claim 4, wherein said controller decreases an electrical current supplied to said rechargeable power source when said electrical current supplied to said rechargeable power source to recharge said rechargeable power source to a state of charge above said threshold value.

6. The AGV system of claim 1, wherein said master controller controls said stationary system power source to recharge said rechargeable power source above a threshold value, and equalize said rechargeable power source.

7. The AGV system of claim 1, wherein said operating condition of said AGV comprises at least one of:

a non-charging command received by said controller on-board said AGV from said stationary master controller; and

an equalization schedule of said rechargeable power source.

21. The AGV system of claim 1, wherein said controller is configured to over-ride a command received from said master controller independent of receiving information from said master controller other than said command when said controller determines said rechargeable power source has an inadequate state of charge to perform said command received from said master controller.

2. (canceled)

8. An automatic guided vehicle (AGV) comprising:

a drive assembly;

a rechargeable power source on-board the AGV, and configured to supply power to said drive assembly; and

a controller on-board the AGV, and configured to substantially continuously monitor at least two conditions comprising of;

an operating condition of the AGV;

a state of charge of said power source; and

an electrical power supplied for recharging said rechargeable power source, wherein said controller dynamically determines when said rechargeable power source of the AGV is to be recharged independent of receiving information from a stationary master controller of an AGV system that comprises the AGV, and controls a recharging process of said power source based upon at least one of said monitored conditions.

10. The AGV of claim 8, wherein said controller determines when said rechargeable power source of said AGV is to be equalized.

11. The AGV of claim 8, wherein said controller determines when said rechargeable power source is to be recharged to a state of charge above a threshold value.

12. The AGV of claim 11, wherein said controller decreases an electrical current supplied to said rechargeable power source when said electrical current supplied to said rechargeable power source to recharge said rechargeable power source to a state of charge above said threshold value.

13. The AGV of claim 8, wherein said operating condition comprises at least one of:

a non-charging command received by said controller from a stationary master controller of an AGV system that comprises the AGV; and

an equalization schedule of said rechargeable power source.

14. The AGV of claim 8, wherein the AGV is included in said AGV system that further comprises a stationary master controller and at least one stationary system power source, wherein said master controller controls said stationary system power source to recharge said rechargeable power source above a threshold value, and equalize said rechargeable power source.

22. The AGV of claim 8, wherein said controller is configured to over-ride a command received from a master controller of said AGV system independent of receiving information from said master controller other than said command when said controller determines said rechargeable power source has an inadequate state of charge to perform said command received from said master controller.

9. (canceled)

15. A method of controlling an automatic guided vehicle (AGV), said method comprising the steps of:

providing a controller on-board the AGV;

monitoring an operating condition of the AGV by said controller;

monitoring a state of charge of a rechargeable AGV power source by said controller;

dynamically determining, by said controller, to recharge said AGV power source based upon said monitored operating condition and said monitored state of charge, wherein said dynamic determination is made independent of receiving information from a master controller of an AGV system that includes the AGV; and

controlling a recharging process by said controller when said AGV power source is recharged, wherein said controlling of said recharging process is independent of receiving information from a master controller of said AGV system that includes the AGV.

17. The method of claim 15 further comprising the step of determining, by said controller, when said rechargeable power source is to be equalized.

18. The method of claim 15 further comprising the step of determining, by said controller, when said rechargeable power source is to be recharged to a state of charge above a threshold value.

19. The method of claim 15, wherein said at least one monitored condition comprises at least one of:

a command received by said controller from a stationary master controller of said AGV system that includes the AGV; and

an equalization schedule of said rechargeable power source.

20. The method of claim 15 further comprising the steps of:

providing an AGV system comprising a master controller and a stationary power source; and

controlling said stationary power source, by said master controller, to recharge said rechargeable power source above a threshold value, and equalize said rechargeable power source.

23. The method of claim 15 further comprising the step of over-riding, by said controller, a command received from a master controller of said AGV system independent of receiving information from said master controller other than said command when said controller determines said rechargeable power source has an inadequate state of charge to perform said command received from said master controller.

16. (canceled)

24. A method of controlling an automatic guided vehicle (AGV) for automatically transporting loads along a predetermined path in at least one of a warehouse, a factory, and a shipyard, said method comprising:

providing a controller on-board the AGV;

providing an AGV system comprising the AGV, a master controller, and a stationary power source;

monitoring an operating condition of the AGV by said controller;

monitoring a state of charge of a rechargeable AGV power source by said controller;

dynamically determining, by said controller, to recharge said AGV power source based upon said monitored operating condition and said monitored state of charge, wherein said dynamic determination is made independent of receiving information from said master controller;

controlling a recharging process by said controller when said AGV power source is recharged, wherein said controlling of said recharging process is independent of receiving information from said master controller;

determining, by said controller, when said rechargeable power source is to be equalized;

determining, by said controller, when said rechargeable power source is to be recharged to a state of charge above a threshold value;

controlling said stationary power source, by said master controller, to recharge said rechargeable power source above a threshold value, and equalize said rechargeable power source; and

over-riding, by said controller, a command received from said master controller independent of receiving information from said master controller other than said command when said controller determines said rechargeable power source has an inadequate state of charge to perform said command received from said master controller.