Patent Application
20190362115
This application relates to calibration, and more particularly to a system for providing calibration data for a device to a controller based on an encoded image.
An aircraft electronic engine control (EEC) typically controls devices such as valves and actuators electronically, and relies on sensors for feedback from the controlled devices. Due to manufacturing differences, the EEC may rely on nominal values that generally apply to a given device, but that do not account for the manufacturing differences between similar devices. A given valve position, for example, may have an associated expected output flow rate that could vary between a same model of valve due to manufacturing differences. It is known to store device-specific calibration values for a valve in a memory circuit that is attached to the valve, and to connect that memory circuit to the EEC.
An example method of calibrating a controller for controlling or sensing data from a device includes decoding an encoded image depicted on a surface associated with a device to obtain an identifier of the device and calibration data for an output of the device. The calibration data is utilized by a controller for one of controlling and sensing data from the device.
An example system for controlling or sensing data from a device includes a device, where a surface associated with the device depicts an encoded image. A controller is configured to control the device or sense data from the device. An imaging device is in communication with the controller, and is configured to read the encoded image. One of the imaging device and controller is configured to decode the encoded image to obtain an identifier of the device and calibration data for an output of the device. The controller is configured to utilize the calibration data for one of controlling and sensing data from the device.
The embodiments, examples, and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible.
The gas turbine engine 10 includes a compressor section 12 that pressurizes air into a combustion section 14 where the air is mixed with fuel and ignited to generate an exhaust gas flow. The exhaust gas flow expands through a turbine section 16 to drive the compressor section 12 and a fan section 18.
The fuel delivery system 20 provides fuel to the combustor section 14. In particular, the fuel delivery system 20 includes a fuel pump 24 that pumps fuel from the fuel tank 22 to a fuel metering unit 26. An output of the fuel pump 24 is proportional to a rotational speed of the gas turbine engine 10. The fuel metering unit 26 includes a metering valve 28, a regulating valve 30, and a shutoff valve 32.
The metering valve 29 controls a rate at which fuel flows from the fuel pump 24 to the compressor section 14. The regulating valve 30 maintains a pressure drop across the metering valve 28 at an approximately constant value. The shutoff valve 32 is operable to shutoff the flow of fuel from the fuel pump 24 to the combustor section 14.
An electronic engine controller (EEC) 34 is configured to control operation of the metering valve 28 and shutoff valve 32. The EEC 34 utilizes a linear variable differential transformer (LVDT) 36 as a sensor to determine a position of a spool of the metering valve 28.
The EEC 34 also utilizes a flow meter 38 to determine a flow rate of fuel provided by the fuel metering unit 26 to the combustor section 14. The EEC 34 utilizes a pressure sensor 39 to determine an air pressure in the gas turbine engine 10 (e.g., in the compressor section 12).
The EEC also controls an actuator 40 of the gas turbine engine, and determines a position of a movable portion of the actuator 40 using a LVDT 42.
Although not shown in
As discussed in greater detail below, at least one device controlled by the EEC 34 (e.g., metering valve 28 or actuator 40) or sensor utilized by the EEC 34 (e.g., flow meter 38 or pressure sensor 39) has an associated encoded image depicted on a surface associated with the device that stores calibration data for an output of the device in an encoded format, such as a known two dimensional barcode format (e.g., a Quick Response “QR” code format).
An encoded image 56 is depicted on a surface associated with the metering valve 28. In the example of
The encoded image 56 in
In one example, the imaging device 70 reads the image, and transmits the image to the EEC 34 through a wired or wireless connection for decoding. In another example, the imaging device 70 performs the decoding, and transmits the decoded calibration data to the EEC 34 through the wired or wireless connection.
The EEC 34 utilizes the calibration data for controlling the metering valve 28, so that the metering valve 28 can be controlled based on an individual characteristic of the valve (e.g., manufacturing differences) that would otherwise cause slight performance differences between the valve and other valves of the same model. By utilizing the calibration data, the EEC 34 can more accurately control the metering valve 28.
In one example, the EEC 34 utilizes the calibration data to determine a mapping between positions of the valve spool 52 and output flow rates of the metering valve 28. This may include the EEC 34 creating a new mapping, or updating a predefined mapping that uses nominal values.
In one example, the EEC 34 includes predefined nominal valves for a class of metering valves that map predefined valve positions of the valve spool 52 to corresponding output flow rates for a class of metering valve 28 at those valve positions, but those nominal values do not account for manufacturing differences between different metering valves of the class (e.g., model). The EEC 34 is configured to update those nominal values based on the calibration data from the encoded image 56 so that the predefined valve positions of the valve spool 52 are mapped more accurately to output flow rates of the metering valve 28.
In one example, if the EEC 34 lacks such nominal values, the EEC 34 instead creates an initial mapping between positions of the valve spool 52 to particular output flow rates for the metering valve 28 based on the calibration data from the encoded image 56.
Although depicted as a barcode scanner, it is understood that the imaging device 70 could include a camera configured to take a photograph of the encoded image 56 instead of scanning it.
An encoded image 56 is depicted on a surface associated with the actuator 40. In the example of
The EEC 34 utilizes the calibration data in a similar manner to that described above, by creating or updating a mapping for the actuator 40 based on the calibration data, and then utilizes that mapped calibration data when controlling movement of the forcer rod 60 to achieve greater accuracy in forcer rod 60 positions.
In a similar manner, the flow meter 38 and pressure sensor 39 could have an encoded image 56 depicted on a surface associated with those devices (e.g., an exterior surface of the devices themselves).
The memory 204 includes at least one non-volatile memory element (e.g., ROM, hard drive, tape, CD-ROM, etc.) and may also include at least one volatile memory elements (e.g., random access memory (RAM, such as DRAM, SRAM, SDRAM, VRAM, etc.)). A non-volatile portion of the memory 304 stores calibration data for one or more devices (e.g., metering valve 28 and/or actuator 40). In one example, the memory 204 is part of a Data Storage Unit (DSU) of an aircraft gas turbine engine.
The at least one I/O device 206 is configured to facilitate communication between the controller 200 and other devices, such as the controlled valves 28, 32 and sensors 36, 38, 39, 42. The at least one I/O device 206 is configured to communicate with the imaging device 70 using a wired or wireless interface. In one example, the at least one I/O device 260 includes a wireless transceiver for wirelessly communicating with the imaging device 70.
The processor 202 is configured to sense data from one or more of the sensors 36, 38, 39, 42 to operate one or more of the devices 28, 40, to achieve a desired operation of the gas turbine engine 10. In some examples, the processor 202 is configured to decode an encoded image provided by the imaging device 70.
The memory 304 includes at least one non-volatile memory element (e.g., ROM, hard drive, tape, CD-ROM, etc.) and may also include at least one volatile memory elements (e.g., random access memory (RAM, such as DRAM, SRAM, SDRAM, VRAM, etc.)).
The at least one I/O device 306 includes a transceiver configured to communicate with the EEC 34 wirelessly or over a wired connection.
The processor 302 is configured to utilize the imaging sensor 308 to read an encoded image 56 from a device to obtain calibration data for the device. The imaging sensor 308 can include a barcode scanning element or a photographic image sensor, for example. In one example, the processor 302 is operable to decode the encoded images it reads before transmitting them to the controller 200.
Use of the encoded images 56 provides for efficient updates to the EEC 34 when a part needs to be replaced, because configuration data for that part can be quickly obtained from its encoded image 56 and provided to the EEC 34.
Some prior art systems have included calibration data on a memory element that is mounted to a valve in a fuel metering unit of a gas turbine engine, which subjects the memory element to the harsh operating environment of the engine during use of the engine. The techniques discussed herein are superior because reliance upon such memory elements is not required. Also, wiring that would otherwise be needed to connect a controller to such memory elements can be omitted, thereby improving reliability and reducing weight.
Although particular types of devices are discussed above (e.g., valves, actuators, and sensors), the techniques discussed herein are not limited to those particular devices. Also, although
Although example embodiments have been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this disclosure. For that reason, the following claims should be studied to determine the scope and content of this disclosure.
