CN112880617A - Free gap real-time monitoring method based on spectrum estimation - Google Patents
Free gap real-time monitoring method based on spectrum estimation Download PDFInfo
- Publication number
- CN112880617A CN112880617A CN202110034388.7A CN202110034388A CN112880617A CN 112880617 A CN112880617 A CN 112880617A CN 202110034388 A CN202110034388 A CN 202110034388A CN 112880617 A CN112880617 A CN 112880617A
- Authority
- CN
- China
- Prior art keywords
- free gap
- peak frequency
- width
- free
- real
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B21/00—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant
- G01B21/16—Measuring arrangements or details thereof, where the measuring technique is not covered by the other groups of this subclass, unspecified or not relevant for measuring distance of clearance between spaced objects
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64F—GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR
- B64F5/00—Designing, manufacturing, assembling, cleaning, maintaining or repairing aircraft, not otherwise provided for; Handling, transporting, testing or inspecting aircraft components, not otherwise provided for
- B64F5/60—Testing or inspecting aircraft components or systems
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Transportation (AREA)
- Aviation & Aerospace Engineering (AREA)
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
Abstract
The invention relates to a free gap real-time monitoring method based on spectrum estimation, which utilizes the frequency response of a free gap to monitor the gap width in real time and utilizes a least square method to fit the functional relation between the free gap width and the peak frequency. The method can greatly reduce the labor time cost, remarkably improve the measurement precision, ensure that the measurement mode is more automatic, and simultaneously avoid the abrasion of parts caused by the friction between a measurement tool and a free gap. Most importantly, the scheme enables the aircraft to monitor the free gap in real time in the navigation process, and provides technical support for the safe flight of the aircraft.
Description
Technical Field
The invention belongs to the field of aircraft engines, and particularly relates to a free gap real-time monitoring method based on spectrum estimation.
Background
Free clearances are widely present in the handling parts of mechanical structures in the aerospace field, and these clearances are essentially generated by the need for a clearance fit between the parts due to the need for rotation of the rotating parts, such as bolt ramps, hinges, and actuators. As the working time of the aircraft increases, the free gaps gradually expand and are overloaded, so that flutter, deviation and aeroelastic instability of control surfaces, blades and the like occur. When the width reaches a certain level, even structural resonance can be caused, so that the risk of metal fatigue failure is increased. Therefore, whether the monitoring free gap is always in a reasonable range or not has important significance on flight safety, performance guarantee and whole machine service life.
At present, the measurement thought of the free gap in the movable part at home and abroad mainly focuses on the direct measurement by using a feeler gauge (also called a gap gauge) or a free gap measuring device. Before the feeler gauge is measured, a part to be measured is disassembled, and then the feeler gauge is plugged into the gap for measurement. In foreign technology, a probe method is also used for nuclear measurement, namely, a blade tip discharge mode is adopted, a probe with external direct current voltage is moved along the radial direction by a motor, and when the probe moves to a blade tip until discharge occurs. The stroke of the probe and the initial installation clearance, namely the difference between the stroke of the probe and the distance from the probe to the inner surface of the casing in a static state, namely the clearance between the blades. However, the probe method is complicated to operate and is only suitable for experimental research. The prior free gap measuring device in China generally comprises a mounting seat and a measuring component, wherein a part to be measured is mounted on the mounting seat, and the measuring component is used for contact measurement. However, the method is the same as the feeler gauge, and only can be used for measuring after being disassembled, and dynamic measurement cannot be realized.
In summary, the existing free gap measurement scheme has the following disadvantages:
1) the free clearance measurement of the movable part requires the disassembly of the part, which wastes time and labor and has overlong measurement period;
2) the thickness of the feeler gauge is discontinuous, the measurement precision of small parts is insufficient, and the human error is large;
3) during measurement, the measuring tool rubs against the free clearance, and parts can be abraded;
4) the operation is complex, real-time measurement and automatic measurement cannot be carried out, and the measurement result cannot be converted into an electric signal.
Disclosure of Invention
The technical problem solved by the invention is as follows: in order to overcome the defects of the existing free gap measurement, the invention relates to a free gap real-time monitoring method based on spectrum estimation, which enables the real-time monitoring of the free gap during the navigation process of an aircraft to be possible and provides technical support for the safe flight of the aircraft.
The technical scheme of the invention is as follows: a free gap real-time monitoring method based on spectrum estimation is characterized by comprising the following steps:
step 1: installing a signal measurement device in a free gap system;
step 2: the method comprises the following steps of performing a test in advance, acquiring a free gap system structure response signal under different free gap widths by a signal measuring device, and transmitting the structure response signal to a computer to obtain a peak frequency; fitting a relation curve of the peak frequency of the frequency response of the free gap system and the width of the free gap, namely f-fpw, by a least square method, and simultaneously storing the f-fpw obtained by the test in a computer;
and step 3: in the process of navigation, a measuring device measures a structural response signal of a free gap system, the response signal is input into a computer to calculate the peak frequency, the current peak frequency f is matched with an f-fpw curve, the free gap width value on a corresponding peak frequency coordinate is checked to obtain the current free gap width, and the current free gap width is regarded as the current free gap width in the process of navigation, so that the real-time monitoring of the free gap is realized.
The further technical scheme of the invention is as follows: the maximum diameter of the signal measuring device is smaller than the width of the free gap.
Effects of the invention
The invention has the technical effects that: the method can reduce the labor cost required by measurement, has high measurement speed, obviously improves the measurement precision, has more automatic measurement mode, completely does not need manual operation in the whole process, converts physical quantity into electric signals and processes the electric signals through a computer, and simultaneously avoids the abrasion of parts caused by the friction between a measurement tool and the parts. Most importantly, the scheme enables the aircraft to monitor the free gap in real time in the navigation process, and provides technical support for the safe flight of the aircraft.
Drawings
FIG. 1 Gear fit Clearance
FIG. 2 is a graph of peak frequency versus free gap width
FIG. 3 least squares fitting results
FIG. 4 free gap real-time monitoring process
Detailed Description
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.
Referring to fig. 1-4, for a free gap system, the free gap width is different and the frequency characteristic of the output signal is different for a given input signal, and the position and magnitude of the first peak are changed. Based on the characteristic, the scheme provides a novel free gap real-time monitoring method based on spectrum estimation, the gap width is monitored in real time by using the frequency response step 2 and the step 3 of the free gap, and the functional relation between the free gap width and the peak frequency is fitted by using a least square method.
The method utilizes the frequency characteristic of the free gap structure response signal to monitor the gap width in real time, and simultaneously utilizes the least square method to fit the functional relation between the peak frequency and the free gap width.
The basic idea of the method is divided into two parts: firstly, a signal measuring device is installed in a free gap system, free gap frequency response characteristics under different widths are obtained in a ground test, and a least square method is used for fitting a functional relation between peak frequency and free gap width, namely f-fpw). Secondly, in the process of flying the aircraft, the response signals acquired by the measuring device are matched with the fitted f-fpw function, the width of the current free gap is judged, and real-time monitoring is completed.
In this embodiment, the free gap system is composed of two gears and a gap between the two gears as shown in fig. 1, and the signal measuring device is an acceleration sensor. The method steps are shown in fig. 4:
step 1: the signal measuring device will first be installed in a free gap system;
step 2: the signal measuring device obtains free gap system structure response signals under different free gap widths, and transmits the structure response signals to the computer to obtain peak frequency; fitting a relation curve of the peak frequency of the frequency response of the clearance system and the width of the free clearance, namely f-fpw, by a least square method, and storing the f-fpw obtained by the test in a computer, wherein the calculation of the peak frequency and the least square fitting are realized by matlab software.
And step 3: in the process of navigation, a measuring device measures a structural response signal of a free gap system, the response signal is input into a computer to calculate the peak frequency, the current peak frequency f is matched with an f-fpw curve, the free gap width value on a corresponding peak frequency coordinate is checked to obtain the current free gap width, and the current free gap width is regarded as the current free gap width in the process of navigation, so that the real-time monitoring of the free gap is realized.
As can be seen from fig. 2, the peak frequency of the free gap system response signal has a downward trend as the free gap width (horizontal axis) increases. The horizontal axis is the free gap width and the vertical axis is the peak frequency.
From fig. 3, it can be seen that a smooth curve is obtained by least square fitting, and the fitting effect is good. The horizontal axis is the free gap width and the vertical axis is the peak frequency. For example, as can be seen from the fitted curve of FIG. 3, the free gap width is 0.75X 10 at a peak frequency of 7Hz-3m。
Claims (2)
1. A free gap real-time monitoring method based on spectrum estimation is characterized by comprising the following steps:
step 1: installing a signal measurement device in a free gap system;
step 2: the method comprises the following steps of performing a test in advance, acquiring a free gap system structure response signal under different free gap widths by a signal measuring device, and transmitting the structure response signal to a computer to obtain a peak frequency; fitting a relation curve of the peak frequency of the frequency response of the free gap system and the width of the free gap, namely f-fpw, by a least square method, and simultaneously storing the f-fpw obtained by the test in a computer;
and step 3: in the process of navigation, a measuring device measures a structural response signal of a free gap system, the response signal is input into a computer to calculate the peak frequency, the current peak frequency f is matched with an f-fpw curve, the free gap width value on a corresponding peak frequency coordinate is checked to obtain the current free gap width, and the current free gap width is regarded as the current free gap width in the process of navigation, so that the real-time monitoring of the free gap is realized.
2. The method of claim 1, wherein the maximum diameter of the signal measuring device is smaller than the width of the free gap.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110034388.7A CN112880617A (en) | 2021-01-12 | 2021-01-12 | Free gap real-time monitoring method based on spectrum estimation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110034388.7A CN112880617A (en) | 2021-01-12 | 2021-01-12 | Free gap real-time monitoring method based on spectrum estimation |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112880617A true CN112880617A (en) | 2021-06-01 |
Family
ID=76045074
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110034388.7A Pending CN112880617A (en) | 2021-01-12 | 2021-01-12 | Free gap real-time monitoring method based on spectrum estimation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112880617A (en) |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010045957A (en) * | 2008-08-18 | 2010-02-25 | Yaskawa Electric Corp | Motor control device and backlash identifying method |
| CN103537797A (en) * | 2013-09-11 | 2014-01-29 | 上海交通大学 | Method and system for detecting laser overlap welding clearances based on plasma images |
| CN103878479A (en) * | 2014-03-06 | 2014-06-25 | 上海交通大学 | On-line detecting method for laser welding T-type overlap joint gaps based on spectrum analysis |
| WO2016030227A1 (en) * | 2014-08-29 | 2016-03-03 | Asml Netherlands B.V. | Method for controlling a distance between two objects, inspection apparatus and method |
| CN105890856A (en) * | 2016-04-05 | 2016-08-24 | 中国科学院力学研究所 | Clearance decoupling identification method of double-clearance mechanical mechanism |
| CN109910309A (en) * | 2019-01-31 | 2019-06-21 | 南京航空航天大学 | Intermediate gap measurement-compensation robot and gap compensation method are assembled for multiple material |
| CN111006873A (en) * | 2019-12-05 | 2020-04-14 | 中国航发四川燃气涡轮研究院 | Method and device for acquiring peak value in blade tip clearance signal processing process |
| CN111241609A (en) * | 2020-01-20 | 2020-06-05 | 西北工业大学 | Prediction method for blade tip clearance of rotor and stator assembly of aircraft engine |
| CN111536887A (en) * | 2020-06-24 | 2020-08-14 | 中国航空工业集团公司北京长城计量测试技术研究所 | Engine blade tip clearance measurement system based on optical frequency comb spectral interference |
-
2021
- 2021-01-12 CN CN202110034388.7A patent/CN112880617A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2010045957A (en) * | 2008-08-18 | 2010-02-25 | Yaskawa Electric Corp | Motor control device and backlash identifying method |
| CN103537797A (en) * | 2013-09-11 | 2014-01-29 | 上海交通大学 | Method and system for detecting laser overlap welding clearances based on plasma images |
| CN103878479A (en) * | 2014-03-06 | 2014-06-25 | 上海交通大学 | On-line detecting method for laser welding T-type overlap joint gaps based on spectrum analysis |
| WO2016030227A1 (en) * | 2014-08-29 | 2016-03-03 | Asml Netherlands B.V. | Method for controlling a distance between two objects, inspection apparatus and method |
| CN105890856A (en) * | 2016-04-05 | 2016-08-24 | 中国科学院力学研究所 | Clearance decoupling identification method of double-clearance mechanical mechanism |
| CN109910309A (en) * | 2019-01-31 | 2019-06-21 | 南京航空航天大学 | Intermediate gap measurement-compensation robot and gap compensation method are assembled for multiple material |
| CN111006873A (en) * | 2019-12-05 | 2020-04-14 | 中国航发四川燃气涡轮研究院 | Method and device for acquiring peak value in blade tip clearance signal processing process |
| CN111241609A (en) * | 2020-01-20 | 2020-06-05 | 西北工业大学 | Prediction method for blade tip clearance of rotor and stator assembly of aircraft engine |
| CN111536887A (en) * | 2020-06-24 | 2020-08-14 | 中国航空工业集团公司北京长城计量测试技术研究所 | Engine blade tip clearance measurement system based on optical frequency comb spectral interference |
Non-Patent Citations (1)
| Title |
|---|
| 陈思雨等: "间隙对含摩擦和时变刚度的齿轮***动力学响应的影响", 《机械工程学报》, vol. 45, no. 08, 15 August 2009 (2009-08-15), pages 119 - 124 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112161803B (en) | Rolling bearing life-span energy consumption testing machine under combined load | |
| CN106482627B (en) | A kind of testing stand and method for being used to measure bearing Radial windage | |
| CN205426517U (en) | Lathe main shaft comprehensive properties detection / monitoring testing system | |
| CN110397613B (en) | Method for measuring gap of compressor with integral structure | |
| KR102224333B1 (en) | An inspection system of spindle run-out in cnc machines and a method thereof | |
| CN105466329A (en) | Non-contact engine turbine blade tip radial gap measurement method | |
| CN112304600A (en) | Fault testing system and fault diagnosis method for single or multiple coupled rotor systems | |
| CN109141302B (en) | Impeller detection method based on least square method | |
| CN106404412A (en) | Device for measuring the eccentric position of the aero-engine bearing holder | |
| CN112880617A (en) | Free gap real-time monitoring method based on spectrum estimation | |
| CN103063333A (en) | Airplane frame part assembly stress detection and control method | |
| CN111912613A (en) | Test bed and test method for measuring rotation precision of electric spindle under alternating load effect | |
| CN110919606A (en) | Automatic leveling and aligning device | |
| CN109696286A (en) | A kind of high-speed electric main shaft dynamically load vibration measurement device | |
| CN114264267B (en) | Ultra-precise angle sensor circumference angle detection system | |
| CN111579236B (en) | Automatic cantilever type dent resistance measuring equipment and measuring method | |
| CN113865519A (en) | Concentricity assembly quality detection device and method | |
| CN207850212U (en) | A kind of internal thread hole online automatic detection no-go gage device of complexity die cast part | |
| CN201863050U (en) | Tool setting device for omega type seal welding seam cutter of control rod drive mechanism | |
| CN110296837B (en) | Sliding bearing load measuring method based on bearing bush deformation | |
| CN112728300B (en) | Leveling system | |
| CN106593551B (en) | A kind of Large Steam Turbine Sets touch the control method of cylinder test | |
| CN220818872U (en) | Device for measuring radial expansion deformation of high-speed rotating rotor | |
| CN214577541U (en) | Laser displacement sensor mounting bracket for measuring wind turbine main shaft assembly movement | |
| CN113983969B (en) | Aeroengine clearance measurement method based on high-energy X-rays |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20210601 |
|
| WD01 | Invention patent application deemed withdrawn after publication |