Papers by Keyword: Coordinate Metrology

Abstract: The measurement of a part on a coordinate measuring machine may be affected by many factors such as machine frame accuracy, probe configuration, measuring environment, and measurement strategy. In order to understand the effect of some of those factors on measurements performed in industrial-grade machines, a master production workpiece has been chosen and circulated in Brazilian industries for collecting data points of the calibrated workpiece features according to a predefined master measuring protocol. Conclusions could be drawn about the behavior of each machine under varying conditions, measurement divergences from similar machines operating under distinct conditions, the complexity of measurements with CMMs, and the need for good measurement practices in the productive sector.

Abstract: Coordinate Measuring Machine (CMM) is nowadays widely used for a large range of accurate and precise dimensional measurements. The strategy of µ-scale measurement is expected to carry out with ever-increasing performance in term of root error separation for stylus system and CMM machine accuracy. The experimental analysis method in this paper aims to study the effect of dynamic root errors at different undulations per revolution (UPR) response of artifact measurement using selected two types of CMM touch-triggering stylus. Direction of stylus characteristics and stylus speed parameters were adopted and emphasized upon throughout the course of experiment. The results were investigated using Fourier analysis could thus be derived to ensure foreseeable accurate and precise results of CMM machine and stylus errors. Some specific error equations for stylus system and machine responses have been postulated and analysed empirically. The results may also employ validating an experimental investigation to detection accuracy development using PRISMO-Bridge-CMM-type in NIS.

Abstract: This paper presents a system of 3-D micro structure measurement that uses an optical fiber probe of 5 µm in diameter. The probe is deflected when it comes into contact with a measured surface, and this deflection is measured optically. In this research, we optimize design parameters of optical system using ray tracing, and a prototype of the measuring system is fabricated on trial to verify the simulation results. Then, its measuring accuracies are examined by using the basic experimental apparatus. As a result, it is clarified that the resolution of the fiber probe is better than 10 nm. Also, the utility of this system is confirmed by measuring the shape of a 600 µm diameter ruby sphere.

Abstract: Achieving traceability is crucial for complex measurement techniques, especially for coordinate measuring machines (CMMs). For CMMs using tactile probes, traceability can for certain measurements be achieved using model-based uncertainty budgets. Up to now, uncertainty simula-tions could be used applicable only for tactile CMM measurements of regular geometries, but are available as an add-on for different CMMs. This procedure is accepted by guidelines and inter-national standards (VDI/VDE 2617-7, supplement 1 [1] to GUM). Furthermore, empirical ap-proaches to assess the measurement uncertainty by means of calibrated workpieces or prior know-ledge exist or are under development. These approaches can as a matter of principle also be used for CMMs featuring computed tomography (CT). In this paper, the empirical assessment of the mea-surement uncertainty of the upcoming measurement technology CT [2, 3] will be discussed uniting the present approaches and the current knowledge, with the focus being on the applicability of con-cepts for users in industry. For this purpose, the influences on dimensional CT measurements are analyzed and evaluated, taking the measurement data of a current industrial micro CT system as a basis.

Abstract: As a rather new technology, X-Ray Computed Tomography offers new and promising possibilities in manufacturing metrology in comparison to well-established tactile or optical measurements. The main benefit is the volumetric model which results of each measurement and represents the measurement object holistically with high point density.

Abstract: Metrology plays an important role in the development and commercialisation of micro and nanotechnology. For calibrating versatile micro- and nanoscale standards, a dimensional metrology instrument coupled with multi sensor heads including atomic force microscope (AFM), tactile stylus, laser focus sensor and assembled cantilever probes (ACPs) has been developed. Two kinds of ACPs are highlighted in the paper. One is fabricated by gluing a vertical AFM cantilever to a horizontal AFM cantilever using micro assembling techniques. It is applicable for direct and non-destructive measurements of sidewall surfaces. The other is an ACP ball probe designed for true 3D measurements of micro structures. It is realised by gluing a tungsten wire with a probing sphere ball, 40 ... 120 µm in diameter, to a horizontal AFM cantilever. The ACP ball probe has advantages such as small probing forces (<1µN) and high probing sensitivity. Some typical calibrations on micro and nano structures such as step height, grating and sphere calotte artefact are introduced.