CLOSED-LOOP CABIN PRESSURE CONTROL SYSTEM TEST METHOD WITH ACTUAL PRESSURE FEEDBACK

• US 20090006056A1
• Filed: 11/14/2007
• Published: 01/01/2009
• Est. Priority Date: 06/26/2007
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: HORNER, DARRELL W., Hilzendeger, Timothy J., Biss, Timothy C.
• Granted Patent: US 7,686,680 B2
• Time in Patent Office: Days
• US Class Current: 703/7
• CPC Class Codes: B64F 5/60 Testing or inspecting aircraft components or systems

Abstract

Testing of an aircraft pressure control system may be performed without use of an altitude chamber. Aircraft cabin configuration date may be modeled and used, along with high resolution positional feedback from a simulated valve, to produce a high resolution electrical signal that may represent a simulated cabin pressure. A voltage-to-pressure transducer may convert the electrical signal to a pneumatic signal. The pneumatic signal may be employed to operate a cabin-pressure controller under test. The controller may operate an outflow valve actuator and an attached potentiometer. The potentiometer may produce a feedback signal and closed-loop testing of the aircraft pressure control system may thus be performed. The outflow valve actuator may be operated without being attached to an outflow valve because a simulated aerodynamic load may be applied to the actuator.

Claims

1. A method for testing a system for controlling pressure within an enclosure comprising the steps of:

producing a first electrical signal to simulate pressure within the enclosure;

producing a pneumatic signal that corresponds to the electrical signal;

operating a pressure control system that is being tested responsively to the pneumatic signal;

producing a second electrical signal responsively to the operation of the pressure control system; and

monitoring the second electrical signal against a known performance standard to determine if the pressure control system functions correctly.

2. The method of claim 1 wherein the step of producing the second electrical signal comprises driving a potentiometer with an outflow valve actuator of the pressure control system.

3. The method of claim 2 further comprising employing the second electrical signal in a production of a second simulated pressure of the enclosure.

4. The method of claim 3 further comprising:

generating a continuum of potentiometer signals; and

employing the continuum of potentiometer signals in a production of a continuum of simulated pressures of the enclosure, whereby closed-loop testing of the pressure control system is performed.

5. The method of claim 1 further comprising:

generating configuration data for the enclosure; and

utilizing the configuration data in the step of producing the first electrical signal.

6. The method of claim 1 wherein the step of producing the first electrical signal generates an analog signal with a resolution that corresponds to at least 16-bits of digital resolution.

7. The method of claim 1 wherein the step of operating the pressure control system comprises operating an actuator of an outflow valve without actual operation of an outflow valve.

8. The method of claim 7 wherein the step of operating the actuator is performed with a simulated aerodynamic load applied to the actuator.

9. The method of claim 8 wherein the simulated aerodynamic load is produced with torsion-spring force applied to a shaft of the actuator.

10. A method testing an aircraft cabin-pressure control system, comprising the steps of:

simulating cabin-pressure;

producing an electrical cabin-pressure signal;

converting the electrical cabin-pressure signal to a pneumatic cabin-pressure signal;

operating a controller of the cabin-pressure control system responsively to the pneumatic cabin-pressure signal;

producing an electric feedback responsively to operation of the control system to provide closed-loop testing of the cabin-pressure control system.

11. The method of claim 10 wherein the step of simulating cabin pressure is performed without use of an altitude chamber.

12. The method of claim 10 further comprising:

simulating an altitude; and

producing pneumatic signaling to the controller so that the controller operates responsively to both a simulated cabin pressure signal and a simulated altitude signal.

13. The method of claim 10 further comprising:

modeling aircraft configuration data in digital format; and

wherein the step of producing the electrical cabin-pressure signal is performed responsively to the configuration data and positional feedback from the valve simulator.

14. The method of claim 10 wherein step of producing an electric feedback comprises operating an actuator of an outflow valve and an attached potentiometer to produce an electrical signal that is responsive to operation of the controller.

15. The method of claim 14 wherein:

the step of operating the actuator is performed with a simulated aerodynamic load applied to the actuator; and

the step of operating the actuator is performed without actual operation of an outflow valve.

16. Apparatus for performing testing of an aircraft cabin-pressure control system comprising:

a self-contained transducer for converting an electrical cabin-pressure signal to a pneumatic cabin-pressure signal, the transducer comprising;

a proportioning valve to receive an electrical pressure signal;

a jet pump for producing vacuum in the proportioning valve;

an inlet for positively pressurized air; and

an outlet for a pneumatic pressure signal.

17. The apparatus of claim 16 further comprising:

a cabin pressure simulator for producing the cabin-pressure electrical signal;

a detector for measuring a response of a cabin-pressure control system to the pneumatic signal.

18. The apparatus of claim 17 wherein:

the cabin pressure simulator has at least 16-bits of analog resolution; and

.

the detector can receive an analog signal with at least 16-bits of analog resolution.

19. The apparatus of claim 16 wherein a detector signal is directed to the cabin pressure simulator so that closed-loop testing system for the cabin-pressure control system is provided.

20. The apparatus of claim 16 further comprising:

a processor that models aircraft configuration data; and

wherein the cabin-pressure simulator produces the electrical cabin-pressure signal responsively to the aircraft configuration data and valve positional feedback.