Machine tools error characterization and compensation by on-line measurement of artifact

2009 ◽  
Author(s):  
Abdul Wahid Khan ◽  
Wuyi Chen ◽  
Lili Wu
Keyword(s):  
Machine Tools ◽  
Line Measurement ◽  
Error Characterization ◽  
On Line

A New Method for On-line Measurement of the Straightness Error of Machine Tools Using an Acceleration Sensor

2021 ◽  
Author(s):  
Kuo Liu ◽  
Yiming Cui ◽  
Zhisong Liu ◽  
Jiakun Wu ◽  
Yongqing Wang
Keyword(s):  
Machine Tools ◽  
Signal To Noise Ratio ◽  
Measurement Data ◽  
Geometric Error ◽  
Ar Model ◽  
High Signal ◽  
Line Measurement ◽  
On Line ◽  
Straightness Error ◽  
Zero Phase

Abstract In order to improve the poor efficiency in the measurement of the geometric error of machine tools’ linear axes, this paper has presented a method to measure and restructure the geometric error of linear axes that is based on accelerometers. This method takes advantage of the phenomenon that when acceleration is measured under different measuring speeds, different frequencies and amplitudes are produced. The measurement data of the high signal-to-noise ratio for various velocities was fused together and the straightness error of the measured axis was obtained by integrating the acceleration twice. In order to remove the trend terms error in the integration, a zero phase IIR Butterworth filter was designed, which guarantees the signal’s phase invariance after filtering. The data was continued with the AR model to eliminate the endpoints’ effect in the filtering. The proposed method was verified by numerical values and experiments. The results showed that the proposed method has better robustness, a wider bandwidth and a higher efficiency than the methods of measuring by laser interferometer. It is also able to measure the geometric error of linear axes with an accuracy that reaches the micron scale.

Applications of D-H Notation in Machining and On-Line Measurement of Roller-Gear Cams on 5-Axis Machine Tools

1997 ◽  
Vol 119 (3) ◽  
pp. 393-401 ◽  
Author(s):  
Psang Dain Lin ◽  
Ming Far Lee
Keyword(s):  
Machine Tool ◽  
Machine Tools ◽  
Removal Rate ◽  
Measurement Techniques ◽  
Kinematic Model ◽  
Cutting Speed ◽  
Line Measurement ◽  
Touch Trigger Probe ◽  
On Line ◽  
Nc Data

A kinematic model is presented to aid in the design of cam-profiles and determine the NC data equations using Denavit-Hartenberg (D-H) notation to produce and to measure the dimension accuracy of roller-gear cams on 5-axis machine tools. First, cam profiles are determined based on the conjugate surface theory. Then, D-H notation is employed in the derivation of machine tool ability functions and in the generation of the desired cutter/measuring-probe location matrices. The desired NC data equations are obtained by solving the link variables of the machine tool by equating the machine tool ability function with the tool location matrices. The resultant cutting speed and material-removal rate during machining are also investigated. To verify the validity of this methodology, a designed roller-gear cam was machined and its surfaces were measured through the on-line measurement system equipped with a touch-trigger probe on a 5-axis machine tool. This methodology combines the cam design, machining, and measurement techniques, thus making the production process more flexible, automatic, and controllable.

Thickness Measurement in the AEM by Macintosh-Based Analysis of Two-Beam Convergent Beam Patterns

1990 ◽  
Vol 48 (2) ◽  
pp. 504-505
Author(s):  
John F. Mansfield ◽  
Douglas C. Crawford
Keyword(s):  
Electron Microscope ◽  
Video Camera ◽  
Thickness Measurement ◽  
Specimen Thickness ◽  
Crystalline Materials ◽  
Beam Dynamic ◽  
Line Measurement ◽  
On Line ◽  
Image Position ◽  
Convergent Beam

A method has been developed that allows on-line measurement of the thickness of crystalline materials in the analytical electron microscope. Two-beam convergent beam electron diffraction (CBED) patterns are digitized from a JEOL 2000FX electron microscope into an Apple Macintosh II microcomputer via a Gatan #673 CCD Video Camera and an Imaging Systems Technology Video 1000 frame-capture board. It is necessary to know the lattice parameters of the sample since measurements are made of the spacing of the diffraction discs in order to calibrate the pattern. The sample thickness is calculated from measurements of the spacings of the fringes that are seen in the diffraction discs. This technique was pioneered by Kelly et al, who used the two-beam dynamic theory of MacGillavry relate the deviation parameter (Si) of the ith fringe from the exact Bragg condition to the specimen thickness (t) with the equation:Where ξg, is the extinction distance for that reflection and ni is an integer.

Control Strategies for a Highly Loaded Biological Ammonia Elimination Process

1993 ◽  
Vol 28 (11-12) ◽  
pp. 531-538 ◽  
Author(s):  
B. Teichgräber
Keyword(s):  
Closed Loop ◽  
Control Strategies ◽  
Level Control ◽  
Sludge Dewatering ◽  
Loop Control ◽  
Reject Water ◽  
Line Measurement ◽  
Control Pattern ◽  
On Line ◽  
Treatment Facilities

A nitrification/denitrification process was applied to reject water treatment from sludge dewatering at Bottrop central sludge treatment facilities of the Emschergenossenschaft. On-line monitoring of influent and effluent turbidity, closed loop control of DO and pH, and on-line monitoring of nitrogen compounds were combined to a three level control pattern. Though on-line measurement of substrate and product showed substantial response time it could be used to operate nitrification/denitrification within process boundaries.

On-line measurement of pulverized coal fineness on a 300 MWe power plant with pulsed digital inline holography

2021 ◽  
Author(s):  
Qiwen Jin ◽  
Xijiong Chen ◽  
Pei Li ◽  
Yonggang Zhou ◽  
Yingchun Wu ◽  
...  
Keyword(s):  
Power Plant ◽  
Pulverized Coal ◽  
Line Measurement ◽  
On Line
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