Automation system with integrated safe and standard control functionality

• US 20070168077A1
• Filed: 09/30/2005
• Published: 07/19/2007
• Est. Priority Date: 09/30/2005
• Status: Active Grant

• Current Assignee: Rockwell Automation Technologies Incorporated (Rockwell Automation, Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Rockwell Automation, Inc.)
• Inventors: Schuster, George
• Granted Patent: US 7,933,676 B2
• Time in Patent Office: Days
• US Class Current: 700/170
• CPC Class Codes: G05B 19/4061 Avoiding collision or forbidden zones
• CPC Class Codes: G05B 2219/36473 Prohibit teaching if force, speed, acceleration of end effector is out of safe range
• CPC Class Codes: G05B 2219/49152 Feedhold, stop motion if machine door is open, if operator in forbidden zone

Abstract

An industrial control system includes a machine, a machine controller, and a safety controller. The machine controller is operable to identify a need for a human interaction, place the machine into a ready state for the human interaction, and generate a ready message responsive to placing the machine into the ready state. The safety controller is operable to receive the ready message, place the machine into a safe state responsive to receiving the ready message, and provide a human interaction indication responsive to placing the machine into the safe state.

Claims

1. An industrial control system, comprising:

a machine having a restricted access portion;

a machine controller operable to identify a need for a human interaction with the restricted access portion during normal machine operation, place the machine into a ready state for the human interaction, and generate a ready message responsive to placing the machine into the ready state; and

a safety controller operable to receive the ready message, place the machine into a safe state responsive to receiving the ready message, and provide a human interaction indication responsive to placing the machine into the safe state that indicates that the machine is ready for human interaction with the restricted access portion.

2. The system of claim 1, wherein the machine controller is operable to place the machine into the ready state by instructing the machine to achieve a ready position.

3. The system of claim 2, wherein the machine is operable to generate an at position message responsive to achieving the ready position.

4. The system of claim 3, wherein the machine controller is operable to disable the machine responsive to receiving the at position message.

5. The system of claim 4, wherein the machine controller is operable to generate the ready message responsive to disabling the machine.

6. The system of claim 2, further comprising a safety-rated sensor operable to generate a safety-rated at position signal responsive to determining the machine is in the ready position, wherein the safety controller is operable to place the machine into the safe state responsive to receiving the safety-rated at position signal.

7. The system of claim 6, wherein the safety controller is operable to inhibit the human interaction indication responsive to the safety-rated sensor not generating the safety-rated at position signal.

8. The system of claim 1, wherein the machine controller is operable to place the machine into the ready state by disabling the machine.

9. The system of claim 1, wherein the safety controller is operable to verify that the machine is in the safe state with no fault conditions prior to providing the human interaction indication.

10. The system of claim 9, wherein the safety controller is operable to inhibit the human interaction indication responsive to identifying a fault condition.

11. The system of claim 1, wherein the machine controller and the safety controller are integrated into a single unit.

12. The system of claim 1, further comprising an energy source coupled to the machine, wherein the safety controller is operable isolate the machine from the energy source to place the machine in the safe state.

13. The system of claim 1, wherein the machine includes a drive unit operable to provide drive signals for the machine and the safety controller is operable to inhibit the drive unit from generating the drive signals to place the machine in the safe state.

14. The system of claim 1, further comprising a protection sensor operable to detect the presence of an operator in a protected region associated with the machine, wherein the safety controller is operable to disable the protection sensor after placing the machine into the safe state.

15. A method for controlling a human interaction with a machine, comprising:

identifying a need for a human interaction during normal machine operation;

placing the machine into a ready state for the human interaction;

generating a ready message responsive to placing the machine into the ready state;

running a series of safety checks to place the machine into a safe state responsive to receiving the ready message; and

providing a human interaction indication responsive to placing the machine into the safe state.

16. The method of claim 15, wherein placing the machine into the ready state further comprises instructing the machine to achieve a ready position.

17. The method of claim 16, further comprising generating an at position message responsive to achieving the ready position.

18. The method of claim 17, wherein placing the machine into the ready state further comprises disabling the machine responsive to receiving the at position message.

19. The method of claim 18, further comprising generating the ready message responsive to disabling the machine.

20. The method of claim 16, further comprising:

generating a safety-rated at position signal responsive to determining the machine is in the ready position using a safety-rated sensor; and

placing the machine into the safe state responsive to receiving the safetyrated at position signal.

21. The method of claim 20, further comprising inhibiting the human interaction indication responsive to not receiving the safety-rated at position signal.

22. The method of claim 15, wherein placing the machine into the ready state further comprises disabling the machine.

23. The method of claim 15, further comprising verifying that the machine is in the safe state with no fault conditions prior to providing the human interaction indication.

24. The method of claim 23, further comprising inhibiting the human interaction indication responsive to identifying a fault condition.

25. The method of claim 15, further comprising isolating the machine from an energy source to place the machine in the safe state.

26. The method of claim 15, wherein the machine includes a drive unit operable to provide drive signals for the machine, and placing the machine in the safe state further comprises inhibiting the drive unit from generating the drive signals.

27. The method of claim 15, further comprising disabling a protection sensor operable to detect the presence of an operator in a protected region associated with the machine after placing the machine into the safe state.

28. canceled

29. An industrial control system for a machine, the system comprising:

a machine controller that provides a ready signal when the machine is positioned for human interaction; and

a safety controller that places the machine in a safety state responsive to the ready signal and provides an indication that the machine is ready and safe for human interaction only after the machine is in the safety state.