CN107932189B - Flutter monitoring method in satellite structure finishing process - Google Patents
Flutter monitoring method in satellite structure finishing process Download PDFInfo
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- CN107932189B CN107932189B CN201711208706.7A CN201711208706A CN107932189B CN 107932189 B CN107932189 B CN 107932189B CN 201711208706 A CN201711208706 A CN 201711208706A CN 107932189 B CN107932189 B CN 107932189B
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- 238000000034 method Methods 0.000 title claims abstract description 32
- 238000012544 monitoring process Methods 0.000 title claims abstract description 28
- 238000007730 finishing process Methods 0.000 title claims abstract description 13
- 238000003801 milling Methods 0.000 claims abstract description 12
- 238000002955 isolation Methods 0.000 claims abstract description 5
- 238000006243 chemical reaction Methods 0.000 claims abstract description 4
- 238000005520 cutting process Methods 0.000 claims description 15
- 238000012545 processing Methods 0.000 claims description 14
- 238000009966 trimming Methods 0.000 claims description 14
- 238000003754 machining Methods 0.000 claims description 11
- 230000002093 peripheral effect Effects 0.000 claims description 7
- 238000004519 manufacturing process Methods 0.000 claims description 5
- 238000010276 construction Methods 0.000 claims description 3
- 238000006073 displacement reaction Methods 0.000 claims description 3
- 238000005259 measurement Methods 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 230000005764 inhibitory process Effects 0.000 abstract 1
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000523 sample Substances 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23Q—DETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
- B23Q17/00—Arrangements for observing, indicating or measuring on machine tools
- B23Q17/12—Arrangements for observing, indicating or measuring on machine tools for indicating or measuring vibration
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01H—MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES
- G01H9/00—Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Automatic Control Of Machine Tools (AREA)
Abstract
The invention discloses a flutter monitoring system and a method in a satellite structure finishing process, wherein the system comprises a numerical control floor milling machine, a numerical control cutter handle, a movable turntable, an adjustable lifting platform, a laser vibrometer, a data collector and an industrial control computer internally loaded with vibration data processing software; the vibration isolation device is characterized in that the adjustable lifting platform is arranged on the ground outside a machine tool vibration isolation ditch through a turntable guide rail, the adjustable lifting platform is slidably arranged above the turntable guide rail, the laser vibration meter is arranged above the adjustable lifting platform, and is connected with the data acquisition unit and an industrial control computer loaded with vibration data processing software through cables for realizing the acquisition of vibration data and the A/D signal conversion; the numerical control tool shank is arranged in a main shaft of the numerical control floor type milling machine. The method can effectively realize flutter monitoring and inhibition in the process of assembling and finishing the satellite structure platform, improve the quality of the finished surface, and reduce the risk of damage to the satellite body caused by flutter in the process of finishing the satellite.
Description
Technical Field
The invention relates to the technical field of machine manufacturing, in particular to a system and a method for monitoring flutter in a satellite structure trimming process.
Background
The satellite structure generally adopts a box-type structure which is formed by combining a barrel plate and a truss and can be repeatedly disassembled and assembled, and needs to provide a fixed installation interface for satellite-borne instruments and equipment and keep certain precision. Because the satellite structure is the thin wall of weak rigidity, truss mostly, the combination processing is maintained the in-process and is produced the flutter easily, can make the depth of cut too big when the amplitude is too big, and the cutting force of cutter increases, and this not only can worsen the quality of machined surface, can't guarantee the position precision of installation face, can damage the star structure even, causes huge loss.
In the traditional satellite finishing process, whether machining vibrates or not is judged according to vibration lines of a cutting face and sound in the cutting process mainly by depending on experience of operators, the vibration condition cannot be judged in real time and quantitatively, and machining risks and difficulty are increased. In view of the defects of the traditional method, the invention innovatively designs a satellite structure trimming process flutter monitoring system and method applied to a satellite structure platform, effectively realizes real-time monitoring of flutter in the satellite structure platform trimming process, optimizes cutting parameters according to the monitoring result, and can meet the requirements of manufacturing precision and quality of the satellite structure platform.
At present, no explanation or report of the similar technology of the invention is found, and similar data at home and abroad are not collected.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a satellite structure platform satellite structure trimming process flutter monitoring system and method, which solve the problems that the machining surface quality is poor, the star body has damage risk and the like in the machining process due to the fact that flutter cannot be judged in real time and quantitatively in the traditional satellite trimming machining process, and are suitable for the assembly and manufacturing process of the satellite structure platform.
The invention is realized by the following technical scheme:
a satellite structure finishing process flutter monitoring system comprises a numerical control floor milling machine, a numerical control cutter handle, a movable rotary table, an adjustable lifting platform, a laser vibration meter, a data acquisition unit and an industrial control computer internally loaded with vibration data processing software; the adjustable lifting platform is arranged on the ground outside the vibration isolation ditch of the machine tool through a turntable guide rail, the adjustable lifting platform is arranged above the turntable guide rail in a sliding manner, the laser vibration meter is arranged above the adjustable lifting platform, and is connected with the data acquisition unit and an industrial control computer loaded with vibration data processing software through cables for realizing the acquisition of vibration data and the conversion of A/D signals; the numerical control tool shank is arranged in a main shaft of the numerical control floor type milling machine.
The invention also provides a flutter monitoring method in the satellite structure trimming process, which comprises the following steps:
step 1: completing the construction of a flutter monitoring system in the satellite structure finishing process;
step 2: hoisting the satellite structure to a movable turntable, and clamping and fixing;
and step 3: installing a dial indicator on a machine tool, measuring a patch on a satellite structure top plate by using the dial indicator, and calculating the processing allowance of the patch according to the measurement data;
and 4, step 4: installing a milling cutter on a numerical control cutter handle of the machine tool, programming a numerical control machining program, setting machining parameters and machining a satellite patch;
and 5: the position of a patch to be processed of the satellite is adjusted by rotating or moving the movable turntable, so that the laser vibration instrument can acquire vibration signals around the patch;
step 6: collecting vibration signals through a laser vibration meter, monitoring the vibration condition in the finishing process according to the amplitude, stopping cutting if vibration occurs, and optimizing the processing parameters again;
and 7: repeating the step 5 and the step 6 to finish the processing of all satellite patches;
and 8: and (5) measuring the precision of the composition plane of the satellite patch, and if the precision does not meet the requirement, repeating the step 5 to the step 7 until the precision meets the requirement.
Preferably, the step 1 specifically includes the following steps:
step 1.1: installing a laser vibration meter (comprising a bracket) on a liftable platform;
step 1.2: adjusting the lifting platform to enable the height of a measuring head of the laser vibrometer to be higher than the machined surface of the satellite structure;
step 1.3: adjusting the angle of a measuring head of the laser vibrometer to enable the laser beam to measure the surface of the structural slab around the processed patch of the satellite structure;
step 1.4: connecting the laser vibration meter with a data acquisition unit through a cable;
step 1.5: setting data acquisition software, wherein the sampling rate is generally 400Hz 0-5500Hz, the time interval is 1/4000s-1/6000s, and the frequency resolution is generally selected to be 1Hz-1.5 Hz; respectively setting an input displacement signal channel and an input speed signal channel; the flutter amplitude is set, and is generally +/-0.01 mm.
Preferably, the step 6 specifically includes the following steps:
step 6.1: the position of the patch to be processed of the satellite is adjusted by rotating or moving the movable turntable, so that the laser vibration instrument can acquire vibration signals around the patch,
step 6.2: a laser emission window of a measuring head of the laser vibration meter emits laser beams to aim at the surface of the peripheral structural plate of the processed patch;
step 6.3: and the data acquisition unit acquires vibration signals, the vibration signals are led into data acquisition software on the industrial control computer in real time through a data interface, the cutting vibration amplitude is recorded and observed in real time, and if the vibration amplitude is larger than the set flutter amplitude, cutting is stopped, and the processing parameters are reset.
Preferably, the step 5 specifically includes the following steps:
step 5.1: moving or rotating the rotary table according to the position of the processed patch, so that the laser beam emitted by the measuring head of the laser vibrometer can monitor the surface of the peripheral structure of the patch;
step 5.2: and if the laser beam is interfered by the machine tool spindle and the patch cannot be detected, adjusting the height and the angle of the laser vibration meter.
Compared with the prior art, the invention has the following beneficial effects: the flutter monitoring system and the flutter monitoring method in the satellite structure finishing process can monitor the flutter condition in the satellite structure finishing process in real time, optimize cutting parameters according to the monitoring result, reduce the damage risk of the satellite structure and meet the manufacturing precision and quality requirements of a satellite structure platform; the invention has wide application prospect in the field of aerospace, can be popularized to other industries with similar requirements, and has considerable economic benefit.
Drawings
Fig. 1 is a schematic diagram of an overall structure of a flutter monitoring system in a satellite structure trimming process in a working state.
Fig. 2 is a diagram of a system for monitoring flutter during a satellite structure trimming process according to the present invention.
FIG. 3 is a flow chart illustrating the steps of a method for monitoring flutter during the trimming process of a satellite structure according to the present invention.
In the figure: 1-numerical control floor milling machine; 2-satellite architecture; 3-mounting a patch on a satellite structure load; 4-a movable turntable; 5-a turntable guide rail; 6-adjustable lifting platform; 7-laser vibrometer; 8-numerical control tool shank; 9-mounting a support of the laser vibration meter; 10-a data collector; 11-an industrial control computer internally loaded with vibration data processing software; 12-laser beam emitted by laser vibrometer; 13-cable.
Detailed Description
The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.
As shown in fig. 1-2, an embodiment of the present invention provides a satellite structure trimming process flutter monitoring system, which includes a numerically controlled floor milling machine 1, an adjustable lifting platform 6, a laser vibration meter 7, a laser vibration meter mounting bracket 9, a data collector 10, and an industrial control computer 11 loaded with vibration data processing software, wherein the adjustable lifting platform 6 is fixed on the ground outside a vibration isolation trench of the machine tool, the laser vibration meter 7 is mounted to the laser vibration meter mounting bracket 9 and placed above the adjustable lifting platform 6, the height and the position of the adjustable lifting platform are adjusted to ensure that the height of a probe of the laser vibration meter is higher than a processed surface of a satellite structure and a laser beam can monitor a surface of a structural slab around a processed patch, the laser vibration meter 7 is connected with the data collector 10 through a cable to realize acquisition of vibration data and a/D signal conversion, the data acquisition unit 10 is connected with an industrial control computer 11 through a cable 13 to realize vibration data processing, and the numerical control tool shank 8 is arranged in a main shaft of the numerical control floor milling machine 1.
As shown in fig. 3, an embodiment of the present invention further provides a method for monitoring flutter during a satellite structure trimming process, including the following steps:
step 1: finishing the construction of a flutter monitoring system in the satellite structure finishing process, specifically comprising:
step 1.1: installing a laser vibration meter (comprising a bracket) on a liftable platform;
step 1.2: adjusting the lifting platform to enable the height of a measuring head of the laser vibrometer to be higher than the machined surface of the satellite structure;
step 1.3: adjusting the angle of a measuring head of the laser vibrometer to enable the laser beam to measure the surface of the structural slab around the processed patch of the satellite structure;
step 1.4: connecting the laser vibration meter with a data acquisition unit through a cable;
step 1.5: setting data acquisition software, wherein the sampling rate is generally 400Hz 0-5500Hz, the time interval is 1/4000s-1/6000s, and the frequency resolution is generally selected to be 1Hz-1.5 Hz; respectively setting an input displacement signal channel and an input speed signal channel; the flutter amplitude is set, and is generally +/-0.01 mm.
Step 2: hoisting the satellite structure to a movable turntable, and clamping and fixing;
and step 3: installing a dial indicator on a machine tool, measuring a patch on a satellite structure top plate by using the dial indicator, and calculating the processing allowance of the patch according to the measurement data;
and 4, step 4: installing a milling cutter on a numerical control cutter handle of the machine tool, programming a numerical control machining program, setting machining parameters and machining a satellite patch;
and 5: the position of a patch to be processed of the satellite is adjusted by rotating or moving the movable turntable, so that the laser vibration instrument can acquire vibration signals around the patch; specifically comprises
Step 5.1: moving or rotating the rotary table according to the position of the processed patch, so that the laser beam emitted by the measuring head of the laser vibrometer can monitor the surface of the peripheral structure of the patch;
step 5.2: and if the laser beam is interfered by the machine tool spindle and the patch cannot be detected, adjusting the height and the angle of the laser vibration meter.
Step 6: collecting vibration signals through a laser vibration meter, monitoring the vibration condition in the finishing process according to the amplitude, stopping cutting if vibration occurs, and optimizing the processing parameters again; the method specifically comprises the following steps:
step 6.1: the position of the patch to be processed of the satellite is adjusted by rotating or moving the movable turntable, so that the laser vibration instrument can acquire vibration signals around the patch,
step 6.2: a laser emission window of a measuring head of the laser vibration meter emits laser beams to aim at the surface of the peripheral structural plate of the processed patch;
step 6.3: and the data acquisition unit acquires vibration signals, the vibration signals are led into data acquisition software on the industrial control computer in real time through a data interface, the cutting vibration amplitude is recorded and observed in real time, and if the vibration amplitude is larger than the set flutter amplitude, cutting is stopped, and the processing parameters are reset.
And 7: repeating the step 5 and the step 6 to finish the processing of all satellite patches;
and 8: and (5) measuring the precision of the composition plane of the satellite patch, and if the precision does not meet the requirement, repeating the step 5 to the step 7 until the precision meets the requirement.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes and modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention.
Claims (1)
1. A satellite structure trimming process flutter monitoring method is characterized in that real-time monitoring of flutter in a satellite structure platform trimming process can be achieved, cutting parameters are optimized according to monitoring results, and manufacturing accuracy and quality requirements of a satellite structure platform are met, and the method comprises the following steps:
step 1: completing the construction of a flutter monitoring system in the satellite structure finishing process;
step 2: hoisting the satellite structure to a movable turntable, and clamping and fixing;
and step 3: installing a dial indicator on a machine tool, measuring a patch on a satellite structure top plate by using the dial indicator, and calculating the processing allowance of the patch according to the measurement data;
and 4, step 4: installing a milling cutter on a numerical control cutter handle of the machine tool, programming a numerical control machining program, setting machining parameters and machining a satellite patch;
and 5: the position of a patch to be processed of the satellite is adjusted by rotating or moving the movable turntable, so that the laser vibration instrument can acquire vibration signals around the patch;
step 6: the laser vibration meter emits laser beams through a laser emission window of a measuring head of the laser vibration meter, aligns the surfaces of the peripheral structural plates of the processed patches to collect vibration signals, monitors the vibration condition in the trimming process according to the amplitude, stops cutting if vibration occurs, and optimizes the processing parameters again;
and 7: repeating the step 5 and the step 6 to finish the processing of all satellite patches;
and 8: measuring the satellite patch composition surface precision, and if the precision does not meet the requirement, repeating the step 5 to the step 7 until the precision meets the requirement;
the method utilizes a flutter monitoring system in the satellite structure finishing process, and comprises a numerical control floor milling machine, a numerical control cutter handle, a movable rotary table, an adjustable lifting platform, a laser vibrometer, a data collector and an industrial control computer internally loaded with vibration data processing software; the adjustable lifting platform is arranged on the ground outside the vibration isolation ditch of the machine tool, the movable turntable is slidably arranged above the turntable guide rail, the laser vibration meter is arranged above the adjustable lifting platform and is connected with the data acquisition unit and an industrial control computer loaded with vibration data processing software through cables for realizing the acquisition of vibration data and the conversion of A/D signals; the numerical control tool shank is arranged in a main shaft of the numerical control floor type milling machine;
the step 1 specifically comprises the following steps:
step 1.1: mounting a laser vibration meter on a liftable platform;
step 1.2: adjusting the lifting platform to enable the height of a measuring head of the laser vibrometer to be higher than the machined surface of the satellite structure;
step 1.3: adjusting the angle of a measuring head of the laser vibrometer to enable the laser beam to measure the surface of the structural slab around the processed patch of the satellite structure;
step 1.4: connecting the laser vibration meter with a data acquisition unit through a cable;
step 1.5: setting data acquisition software, wherein the sampling rate is 400Hz 0-5500Hz, the time interval is 1/4000s-1/6000s, and the frequency resolution is generally selected to be 1Hz-1.5 Hz; respectively setting an input displacement signal channel and an input speed signal channel; setting a flutter amplitude;
the step 6 specifically comprises the following steps:
step 6.1: the position of the patch to be processed of the satellite is adjusted by rotating or moving the movable turntable, so that the laser vibration instrument can acquire vibration signals around the patch,
step 6.2: a laser emission window of a measuring head of the laser vibration meter emits laser beams to aim at the surface of the peripheral structural plate of the processed patch;
step 6.3: the data acquisition unit acquires vibration signals, the vibration signals are led into data acquisition software on an industrial control computer in real time through a data interface, the cutting vibration amplitude is recorded and observed in real time, if the vibration amplitude is larger than the set flutter amplitude, cutting is stopped, and processing parameters are set again;
the step 5 specifically comprises the following steps:
step 5.1: moving or rotating the rotary table according to the position of the processed patch, so that the laser beam emitted by the measuring head of the laser vibrometer can monitor the surface of the peripheral structure of the patch;
step 5.2: and if the laser beam is interfered by the machine tool spindle and the patch cannot be detected, adjusting the height and the angle of the laser vibration meter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711208706.7A CN107932189B (en) | 2017-11-27 | 2017-11-27 | Flutter monitoring method in satellite structure finishing process |
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| CN201711208706.7A CN107932189B (en) | 2017-11-27 | 2017-11-27 | Flutter monitoring method in satellite structure finishing process |
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| CN107932189B true CN107932189B (en) | 2020-04-24 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| TW490357B (en) * | 1999-05-27 | 2002-06-11 | Sanyo Electric Co | Method and device for detecting abnormities of the cutting tool of a cutting machine |
| CN101913105B (en) * | 2010-08-16 | 2012-01-18 | 合肥工业大学 | Non-contact three-dimensional optical measuring head and method for in-situ measurement of numerical control machine |
| CN103372787A (en) * | 2012-04-28 | 2013-10-30 | 台中精机厂股份有限公司 | Intelligent adaptive cutting vibration suppression method and system of tool room machine |
| CN103624633A (en) * | 2013-12-09 | 2014-03-12 | 大连理工大学 | Micro-milling vibration precision measurement system taking laser micro-displacement sensor as measuring element |
| CN104400086B (en) * | 2014-10-10 | 2016-07-06 | 南京航空航天大学 | Aircraft skin mirror image method for milling and equipment |
| CN104842219B (en) * | 2015-02-12 | 2018-10-23 | 上海卫星装备研究所 | A kind of satellite structure platform multi-process intensive style repair System and method for |
| CN105500115A (en) * | 2016-02-24 | 2016-04-20 | 南京工程学院 | Detection system for tool chattering in milling and detection method thereof |
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