• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.10 no.5
• /
• pp.71-77
• /
• 2001

On-machine measuring system of Numerically Control(NC) machines permit computer control of basic material cutting processes of moulds. A part of mould designed within a CAD/CAM system can be manufactured by generation of tool paths by the measuring systems. Since the three-dimensional geometry by AutoCAD of the part is contained in the data base, the manufacturing specialist combined with the appropriate software simulation, can not only create the commands to drive the virtual measuring and standardization of measuring modules but also can check for mistakes by viewing the computer graphics simulation of the tool cutting sequence.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.2 no.3
• /
• pp.56-61
• /
• 2003

This paper described about on-machine profile measurement of aspheric surfaces using contact probing technique in ultra precision machine. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime using a circle leaf spring mechanism and a capacitive-type sensor. The contact probe which is installed on the z-axis is In touch with the aspheric objects which is fixed on the spindle of the diamond turning machine(DTM) during the measuring procedure. The x, z-axis motions of the machine are monitored by a set of two orthogonal plane mirror type laser interferometers. As a results, the developed contact probe on-machine measurement system showed 10 nanometers repeatability with a ${\pm}2{\sigma}$ and uncertainty of 200 nmPv.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2000.10a
• /
• pp.20-25
• /
• 2000

In this paper, a methodology of geometrical error identification and compensation for NC machine tool position. We have proposed a reference artifact with which, in measuring the coordinate system of NC machine, the robust coordinate systems are given. The coordinate system of the NC machine could be compensated successfully with the information obtained by measuring the reference artifact and our compensation algorithm. Monte Carlo simulation is used to evaluate coordinate referencing ability and, the uncertainties of the machine tool position is estimated and observed through the compensation process by simulation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1993.10a
• /
• pp.305-311
• /
• 1993

In recent years, it has been variously developed for testing the accuracy of circular motion of NC machine tools, for example Telescoping Ball Bar Method by Bryan,Circular Test Method by Knapp and r $_{- \theta}$ Mathod by Tsutsumi etc., but it is not yet settled in the code of measuring methods of motion errors of NC machine tools, because of errors of measuring units and sensors, and also especially the difficulties of centering of measuring units. In this paper, in use of magnetic type linear scale with resolution of 0.5 .mu. m and tick pulses come out from computer, it has become possible for detecting of linear displacement of radial errors and measuring of revolution angle of circular motion of NC machine tools.

• 제어로봇시스템학회:학술대회논문집
• /
• 2001.10a
• /
• pp.127.5-127
• /
• 2001

The 3-dimensional measuring machine by using an ultrasonic sensor is used one of the NDE (Nondestructive Evaluation). It is applied to the inspection of pipelines, boreholes, pressure vessel and tank, and so on. On particular when a harsh environment prohibits the use of moving mechanical parts. The 3-dimensional measuring machine by using an ultrasonic sensor, which measure 1-dimensional information and 2-dimensional information simultaneously from a target of inspection, and then re construct 3-dimensional information. So we can find the situation in progress and predict remaining life and corrosion without destructive examination. It´s a point of excellence that the 3-dimensional measuring machine is portable.

• Journal of the Korean Society for Precision Engineering
• /
• v.12 no.10
• /
• pp.121-129
• /
• 1995

The objective of this research is to develop an effective inspection planning strategy for sculptured surfaces by using 3-dimensional Coordinate Measuring Machine (CMM). First, the CAD/CAM database is generated by using the Bezier surface patch mathod and variable cutter step size approach for design and machining of the workpiece model. Then, optimum measuring point locations are determained based on the mean curvature analysis to obtain more effective inspection results for the given sample numbers. An optimal probe sequence generation method is proposed by implementing the Traveling Salesperson (TSP) algorithm and new guide point selection methods are suggested based on the concepts of the variable distance between the first and second guide points. Finally, simulation study and experimental work show the effectiveness of the proposed strategy.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2002.04a
• /
• pp.510-514
• /
• 2002

The 3-dimensional measuring machine by using an ultrasonic sensor is used one of the NDE(Non Destructive Examination). It is applied to the inspection of pipelines, boreholes, pressure vessel and tank, and so on. In particular when a harsh environment prohibits the use of moving mechanical parts. The 3-dimensional measuring machine by using an ultrasonic sensor, which measure 1-dimensional information and 2-dimensional information simultaneously from a target of inspection, and then reembody 3-dimensional information. So we can find the situation in progress and predict remaining life and corrosion without destructive examination. It's a point of excellence that the 3-dimensional measuring machine is portable.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.12
• /
• pp.81-88
• /
• 1998

Measurement and inspection of freeform surfaces are required in reverse design processes. In the case of surface measurement using a touch probe, probe radius compensation affects measuring accuracy. But current industrial practice depends upon an operator's experience to compensate for probe radius. In this paper, an on-the-machine measuring and inspection system for freeform surfaces is studied. Probe radius compensation methodology is investigated by modeling of B-spline surfaces based on digitized data. The accuracy and reliability of the developed system is verified through various kinds of numerical simulations and on-the-machine experiments.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.18 no.9
• /
• pp.2358-2367
• /
• 1994

This paper presents techniques for evaluation and compensation of total measuring errors in a commercial CMM. The probe errors as well as the machine geometric errors are assessed from probing of the mechanical artefacts such as shpere, step, and rings. For the error compensation, the integrated volumetric error equations are considered, including the probe error adn the machine geometric error. The error compensation is performed on the absolute scale coordinate system, in order to overcome the redundant degree of freedom in the CMM with multi-axis probe. A interface box and corresponding software driver are developed for data intercepting/correction between the machine controller and machine, thus the volumetric errors can be compensated in real time with minimum interference to the operating software and hardware of a commercial CMM. The developed system applied to a practical CMM installed on the shop floor, and demonstrated its performance.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1994.10a
• /
• pp.260-265
• /
• 1994

Efforts have been devoted to developing rapid and accurate methods for measuring the errors of machine tools. The method os measurement and calibration of machine tool errors should be general and efficient. The objective of this study is to show in detail the full sequence from the measurement of errors factors to the verification of the positioning accuracy after compensation for the volumetric error. In this paper, we described the steps in measuring the volumetric error parameters, a general error model composed of error parameters, temperature, and the desired position. The validity of the error calibration methods proposed in this paper was tested using a vertical 3-axis CNC machine with a laser interferometer and a ball bar.