Accept rice is measured and three-dimensional the uncertainty of measurement in measuring is decided really

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The overview is measured in nicety in, to evaluating the significance of uncertainty of measurement correctly, people had gained extensive consensus. However, as the one party that should consider traceability, industrial group to run-of-mill the knowledge that surveys evaluation respect rises somewhat, and the controversy that spends surely to traceability and inaccuracy still afoot. The respect is measured in length and appearance, use when measuring an instrument to undertake length is measured commonly, its do not spend need to consider the following factor certainly (see a table 1) : Some inaccuracy spend measuring instrument appliance surely, the inaccuracy that the instrument measures after calibration is spent surely (include to regard calibration as fiducial standard component) , measure the inaccuracy of the process to be spent surely, environmental influence (especially the influence of temperature) wait. The inaccuracy that measures to average length spends those who undertake the evaluation is a likelihood surely, and simpler. The spends certainly main factor that when 1 average length measures, the watch does not spend certainly - affirmatory method ① measures an instrument: Error of repeatability, staff guage - the calibration of technical standard ② of JIS, manufacturer: Fiducial / standard - calibration certificate; Repeatability - experimental ③ measures: Environment: Temperature - experiment, theoretical analysis; Repeatability - experiment the article is measured in the light of accept rice and three-dimensional the evaluation that when measuring, does not spend certainly undertakes elaborating. When undertaking accept rice is measured, if by the watch 1 pair of uncertainty of measurement undertake evaluating, as calibration fiducial standard component becomes a serious problem. When because this is evaluating the inaccuracy that accept rice measures,be being spent surely, need to elaborate accept rice standard component mainly build and decide. And undertaking three-dimensional when measuring, measure measure more complex, must consider a variety of factors, depend on it is very important that the inaccuracy that measures strategy spends an evaluation surely. The situation that measures strategy in the consideration comes down to decide three-dimensional metrical inaccuracy is spent surely, about this respect, the article will clarify the tendercy that standardizes about ISO. The evaluation of accept rice uncertainty of measurement (1) it is very important to semiconductor industry that rice of pay of accept rice level is measured, what industrial group asks establish accept rice is measured strongly is fiducial / standard. Allow as Namiji / standard, the step pitch plan that adopts one dimension, rank compasses, line cost plan and compasses of planar step pitch will decide and build Namiji to allow / standard. Suit with this photograph, in the light of use at building Namiji to allow / of the standard measure machine, each country offerred a variety of program. NPL (British Institute for Standard) research developed 4 kinds to measure machine (see a table 2) , they are in of accept rice standard main effect had in building. Among them use is the most extensive is to measure long AFM (measure microscope of long nuclear power) . Measuring long AFM is the nuclear power microscope that combined laser to measure chief instrument, each national capital is undertaking developing. Watch 2 NPL uses at building Namiji to allow / 4 kinds of of the standard important measuring instruments implement the measuring instrument of exterior surface roughness that ① combines laser to measure chief instrument: NanoSurf ② combines laser to measure the nuclear power microscope of chief instrument: Metric model the combination of AFM ③ optical interferometer and X ray interferometer: 3 coordinate measure COXI ④ high accuracy machine: Small-sized CMMnextpage (2) the compose that measures long AFM into Japanese industry technology metric standard ministry develops comprehensive institute measure long AFM to have current world highest property. Each axis of X, Y, Z contains laser interferometer, use smooth road reflex and electric fractionize, resolution is achieved 0.

04nm. Use 5 lens to will measure an object to put park workbench, as a result of nonexistent Abbe error, reduced the uncertainty of measurement of the instrument. Laser interferometer and the iodic stability that regard a country as domestic length standard changed laser to undertake comparative, ensured traceability. Such fiducial to detecting / the standard, formed a complete measurement that can trace to the source machine. (3) with measure long AFM fiducial to step pitch compasses assignment is expressed 3 measure long AFM to use the main inaccuracy when fiducial to compasses of 240nm step pitch assignment spends an element surely. From inside the watch knowable, to compasses of 240nm step pitch, of laser interferometer nonlinear the error is the mainest factor in measuring inaccuracy of oneself of long AFM instrument to spend an element surely. The measurement that to 240nm this plants step pitch compasses to measure range narrowly the object, because 5 lens were used on the orgnaization, avoided orgnaization error (wait like Abbe error) the effect that this kind of big inaccuracy decides an element. Watch 3 spend main factor inaccuracy to spend main factor surely surely with the inaccuracy when measuring long AFM to survey plan of 240nm step pitch - measuring instrument of standard deviation ① : Of interferometer nonlinear - 0.

12nm; The resolution of interferometer - 0.

02nm; Abbe error - 0.

01nm ② measures object and measure an operation: The inhomogenous sex of material - 0.

09nm; Metrical repeatability - 0.

Because 05nm is fiducial / the disperse sex that standard component makes and place are different, the step pitch plan that creates is standard / standard heterogeneity is become except the one big factor that measures the inaccuracy beyond machine to be spent surely. This allows in Namiji / a typical issue is in the standard. Although developed very good measurement machine, but because measure the appearance deviation of the object to slant big or stability is too poor, should give this fiducial / standard assignment is very difficult also. To compasses of 240nm step pitch fiducial / the example that the standard assigns makes clear, its expand inaccuracy is spent surely can achieve ± 0.

04nm. (4) have an example about the task of accept rice uncertainty of measurement, be in 70nm rank wrong plan is standard / when the standard assigns, the inaccuracy that because of exterior form appearance out of order causes is spent surely exceed 1nm, take rank difference 1% much still, those who be equivalent to the surface of 100mm gauge block having 1mm is uneven. The factor that when this shows in micron class is measured, need not consider measures a lieutenant general to become major problem in accept rice class. Measure in accept rice in, allow with Namiji first normally / the standard comes calibration scanning electron microscope or general AFM, undertake metrical next. Below this kind of circumstance, the assess of uncertainty of measurement is offer Mickey follows / standard inaccuracy is spent surely with measure machine and the inaccuracy that measure an operation to be spent surely add up undertake assess. Namiji is accurate / the proportion that standard inaccuracy spends amid place to occupy surely is not small. This shows, measure in accept rice in, namiji is accurate / the standard is very important. Will be in Japan henceforth, with industrial technology comprehensive institute is a center, the Namiji that prepares Japan is accurate / the standard is very important, implementation high quality is fiducial / ego supply of the standard is necessary and indispensable. The assess of three-dimensional uncertainty of measurement (1) 3 coordinate measure the high accuracy of machine to change 3 coordinate to measure machine use at measuring three-dimensional appearance, dimension to wait, the high accuracy that measures to come true is changed, be necessary to be measured to 3 coordinate above all machine undertake high accuracy calibration. Measure with the 3 coordinate that pass high accuracy calibration next machine undertake three-dimensional when measuring, to ensure its traceability, be necessary to undertake assess to uncertainty of measurement. Be in nowadays ISO/TC213/WG10 (coordinate is measured machine) in the standard, had measured machine precision assess to make a provision to 3 coordinate, be opposite the assess standard of uncertainty of measurement undertakes delibrate. (2) 3 coordinate measure the athletic precision of machine to measure the measurement of machine about 3 coordinate precision, according to the regulation of Japanese JIS B7440-2, the circumstance is measured to fall in dimension, adoption index is MPEE of error of the biggest concessional directive. A 3 coordinate that have door type structure are measured machine, it is a kind of type that has highest precision now. Main technique standard is as follows: · MPEE= (0.

35=L/1000) Mm (when measuring length L=500mm, e=0.

85mm) · temperature limits: 22 ℃ · measures 18 ～ limits: 710mm´710mm´610mm is measured to be mixed in big temperature range tall measurement is obtained inside limits precision, used computer of instrument motion precision to compensate a technology. 3 coordinate measure door type construction the athletic precision state of machine. Come to instrument whole consider as a rigid body, assess the error of circumgyrate of mobile sum of errors on direction of each axis of its X, Y, Z. Consider X axis above all, the position of the linearity on Y axis and Z axis direction and X axis (rear sight) the error regards translation as the error, and twist place, sway and boil place an error to belong to rotational error. Every axis is having the 6 kinds of errors, verticality error between each axis to share 3, the athletic error that the instrument contains has (3´6+3) in all 21 kinds. Use ball plate gauge to come 3 coordinate measure calibration the method of machine. Use turn over facing to be opposite beforehand the central position of each ball undertakes ball plate gauge high accuracy determines assignment. Undertake metrical to ball plate gauge through be on 6 4 different positions, direction, can calculate reach 3 coordinate measure the 21 motion error of machine. The property from ball plate gauge is knowable, computative when the interval that measures a space is big, measuring the error between the space to use polynomial means to have complement computative. Nextpage (3) the assess of 3 coordinate uncertainty of measurement uses 3 coordinate to measure machine when undertaking metrical, to ensure traceability, be necessary to try to evaluate to uncertainty of measurement. The main factor of uncertainty of measurement sees a table 4. Through undertaking evaluation hind to each error elements, computation gives uncertainty of measurement is necessary. Watch 4 three-dimensional metrical inaccuracy spends main factor ① surely 3 coordinate measure the error of machine: Geometrical error, repeatability error; Rear sight resolution; Exploration system error; Error of environment of ② of repeatability error, directional error: The influence of temperature, oscillatory influence ③ measures: Secure method, operation method; ④ of error of exterior surface roughness, appearance measures strategy 3 coordinate measure the measurement of machine the characteristic is its measure strategy. Measure with 3 coordinate machine each plane that measure workpiece and columnar face, beg the included angle between a planar normal and columnar face axes through computation (this included angle in the exemple is 88.

52 ° ) . This is a simple measurement example. To get the inaccuracy of this included angle to be spent surely, outside the error factor that measures machine itself besides 3 coordinate, the amount of the position of measurement point, measurement point measure strategy to also have great sense. Although in same table 3 coordinate are measured,be opposite on machine same those who measure an object inside aperture diameter undertakes metrical, distributing equably in measurement point or inhomogenous distributing, below the situation with measurement point different amount, the inaccuracy that its measure an outcome is spent surely not identical also. The means that takes uncertainty of measurement is sought below politic to considering to measure circumstance, had offerred a variety of program. In ISO15530 file, basically used the following 3 kinds of methods: · measures a way quite (replace a method) · computer emulates a method (the computer is emulated, fictitious coordinate measures chance way) · complex number measures a way (measure for many times) among them, the application of computer emulation standard is most wide. The fictitious coordinate that benefit emulates with the computer measures the essentials of chance method. Use ball plate gauge or standard ball to measure machine and the error of exploration system to undertake evaluating to 3 coordinate, build 3 coordinate to measure the error pattern of machine by computer compose. In this error pattern, because the error presses statistical record, according to be being measured actually strategy undertakes metrical and putting the statistical error that is put in the computer can undertake emulation, use Monte Carlo to emulate, push the inaccuracy that cipher out measures to be spent surely. Fictitious CMM law is put forward by German Institute for Standard above all, after this NEDO establishs a task, japan, Germany, Australia made thorough and careful research to this jointly. (4) assess the benefit such as the measuring instrument of task surface roughness of 3 coordinate uncertainty of measurement, appearance measuring instrument, image measuring instrument undertakes with the computer complex measured measuring instrument already got popular. Measure with 3 coordinate opportunity is same, these calibration methods that measure an instrument and be based on the inaccuracy that measures strategy to spend computational method to have main effect surely. For this, we expect to use the computer to emulate come the method of assess uncertainty of measurement can get further research, solid reality is used change. Conclusion regards nicety as metrical task, be measured to accept rice and three-dimensional the assess current situation of the uncertainty of measurement in measuring undertook elaborating. Henceforth, right more the complex form of high accuracy undertakes efficient it is more important to measure quantitative change to get. Uncertainty of measurement is the evaluation to measuring an outcome not only, and will tell from whole, measure the measurement with taller efficiency to considering to measure cost, compose to build the system also is important. Those who offer assignment of classics high accuracy is fiducial / standard component, those who consider to be aimed at complex uncertainty of measurement, more accurate computer emulates evaluation technology, solid reality is used change, these will be henceforth nicety measures the main task inside the domain. CNC Milling CNC Machining