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The focus of this study is to discuss the metrological performance of a first prototype of a vision-based measurement system targeted to in-production dimensional quality control of turned parts. The instrument exploits telecentric optical profilometry, is characterized by short inspection time and is suitable for automated charge/discharge of the parts to be inspected. Section II discusses those mechanical arrangements targeted to optimize images acquired as well as the main issues that eventual mechanical misalignments of components might introduce in the quality of images. Section III describes a comparison analysis performed on measurements collected both with the aforementioned instrument and other on-the-market devices commonly used in production line. The data acquired are presented in section IV and were useful to evaluate the metrological performance of each instrument and the combination of the variability of the instruments and the variability of the parts.

MicroNimbus is a 3U CubeSat spacecraft that uses a single-chip SiGe 60 GHz radiometer to measure the temperature profile of the Earth's atmosphere. Due to the characteristics of oxygen absorption around 60 GHz, by choosing different center frequencies and bandwidths, the radiometer can measure the temperature of the atmosphere at different altitudes, giving the temperature profile. The temperature profile is of interest to weather forecasters and workers in LIDAR, and laser communications, among others. The CubeSat's low cost would allow a constellation of such spacecraft to be deployed, yielding a continuous near-real-time 3-D map of the temperature profile of the Earth's atmosphere. MicroNimbus is currently in development at the Georgia Tech Research Institute, and is expected to launch at the end of 2018.

This work presents a new class of MEMS based frequency output force and displacement probes with sub-nm displacement resolution. The sensor consists of a probe tip attached to a microcantilever coupled to a thermal-piezoresisitve resonator. Application of a displacement to this probe tip causes deflection of the cantilever due to the applied force. Consequently, the force acting on the cantilever is transferred to the piezoresisitve beam, modulating its stiffness and thus the resonance frequency. Such devices can be used as atomic force microscope (AFM) probes or high resolution surface profilometers with fully electrical operation eliminating the bulky and complex optical detectors typically used in such systems. As a proof-of-concept, such a microcantilever coupled to a 2.1MHz thermal-piezoresisitve resonator has been demonstrated with a displacement sensitivity of 1.5Hz/nm. The Allan deviation for such resonators operated as self-sustained oscillators is measured to be 0.1–0.2ppm. On analysis of the measured data, a frequency resolution in the order of 1Hz is expected to be achievable. This, in turn, translates to ∼0.4nm of displacement and ∼11nN of force resolution for such sensors.

As the well-grown of technology, manifold detecting functions have been developed on the surface measurement. By using diverse physical/chemical effects, the 3D surface profile measurement can be developed to detect the sample surface structure. Through the delicate optical configuration, the astigmatic pick-up head can achieve the nano-scale measurement resolution. Furthermore for realizing a profilometer, the scanning performance also plays a significant function to detect the sample profile. This paper is to present our developed astigmatic profilometer integrated with a coplanar and biaxial electromagnetic scanning stage and an astigmatic pick-up head. The electromagnetic scanning function is based on the moving-coil principle which utilizes the Lorentz force to drive the coil attached to the elastic membrane. Each scanning axis possesses two opposite-working electromagnetic actuators with the pull-push actuation method to symmetrically create large actuating force. It has been experimentally verified that the coplanar and biaxial scanning stage can achieve the scanning range over 1 mm. The astigmatic profilometer can scan an surface area of 1 mm × 1 mm (500 pixels × 500 pixels) at the scanning rate of 20 Hz. Its maximum scanning speed is equivalent to 40 mm/s.

The concept of a real-time profilometer for ion beam is considered in this paper. The profilometer hardware is based on X-Y collector electrodes and the software based on LabVIEW from National Instruments. The software algorithm allows for statistical analysis and the visualization of beam current distribution. The concept of the profilometer was tested on the isochronous Eclipse Cyclotron produced by Siemens.

Gap width control is an important task for friction stir welding (FSW) since assembling gap width greatly influences the welding quality. A new efficient method with on-machine measurement (OMM) system based on 2D laser profilometer has been developed in this paper. The method is divided into three steps. Firstly, kinematics and calibration are analyzed to establish the transform relationship from laser sensor coordinate system to workpiece coordinate system (WCS). Then, width information is obtained by an automatic recognition algorithm. Lastly, compensation strategy based on measurement results is presented. Experiments have been performed to verify the efficiency of the proposed compensation method. The results prove that the method is efficient in improving the accuracy and uniformity of assembling gap width.

This paper proposes a design of a dual-probe profilometer, which successfully utilizes a compensation method with two probe modules to scan a 200 nm step height standard sample with 5% scanning error. Compared with traditional profilometers, this design possesses high scanning precise performance without using large and heavy optical flats to increase the flatness when sample stage is moving. The experimental results show the compensation method is valid and can be applied in nano-scale scanning.

Soil roughness parameters have been traditionally retrieved using altimetric profiles acquired from profilometer devices. Measuring soil roughness using the technology called Terrestrial Laser Scanner (TLS) is an innovative method because of it is possible to get a three-dimensional surface more realistic than previous approaches. This paper shows a comparison between both techniques for different kind of soil roughness. A multilateral-based acquisition is proposed for TLS measurement. Analyses are made with profiles from the same soil samples acquired using a profilometer and a TLS. Profile-to-profile comparison got altimetric correlation between both devices and how soil roughness parameters are affected with. Results offer a straight relation (R=0.92 globlally) between both datasets. The oblique angle used by multilateral acquisition in TLS reports a smoother value than vertical acquisition by profilometer

The paper describes a calibration procedure for a structured-light sinusoidal-fringe profilometer which requires the acquisition of images of a plane in one or more unknown poses when it is illuminated by sinusoidal fringe patterns projected by an illuminator. The procedure does not require specific target but only a planar surface which can be freely moved or rotated around a vertical axis.

We demonstrated a miniaturized optical profilometer of surface scanning manner by using an electrically tunable liquid crystal Fabry-Perot cell. The surface profile of the fringe patterns is explained by the resonance mode analysis of the interference patterns.

SODAR-RASS systems are progressively used for a large number of applications especially in air pollution meteorology. Both quantitative and qualitative information on the atmospheric structure parameters can be obtained with reasonable accuracy. Among others, the mixing height of the atmosphere, the wind and temperature field and the stability class can be determined. This paper studies correlations between certain profilometer-produced estimates of the atmospheric boundary layer (ABL) characteristics and urban air pollution patterns incorporating collected environmental data in Athens, Greece. The recorded air pollution episodes, considering both primary emitted and photochemically produced pollutants, were analyzed along side the ABL characteristics determined by a SODAR-RASS profilometer operating close to the center of the city. First results indicated that sufficiently good correlation exists between relevant profilometer ABL estimates, (e.g. Zi) and the patterns of air pollution encountered over the city.

A new technique is suggested for estimating the profile of an original unworn surface using a profilometer and digital filtering. The profile signals from the digital profilometer are divided into two types: waviness-low frequency signals, and roughness-high frequency signals. The original profile of a wear track was estimated by combining the waviness and the roughness taken from the surface before the wear test. The results of the study show that this technique results in an accurate estimate of the original profile. Comparing the estimated profile of an original unworn surface with the profile of a measured worn surface can be utilized in the calculation of wear volume.

A high sensitive Michelson interferometer with polarization shifting approach is proposed to determine the surface profile of optical devices with real time capability. The depth resolution in nanometer range and the lateral resolution smaller than 3 micrometer is demonstrated experimentally.

An instrument that accurately measures the profile of a surface in a real-time environment is proposed. The theoretical basis of the device is presented, with an explanation of how, through the analysis of fringe patterns using the fast Fourier transform, geometric parameters of a surface can be obtained. Hardware requirements for the proposed device are discussed, showing how the processing power and short cycle time of the TMS 320C25 digital signal processor (DSP) are used. The range of applications of this type of instrument is considered. >

Te "scanning wire" is the most common method of beam profile measurement, where thin wire is transported across the beam and secondary electrons' or radiation are detected. It cannot be used for beams with high power density because the wire cannot sustain a heat load. A possible solution is to substitute the wire by a low-density jet of a metal vapor. Profilometers of this type were successfully used in ion storage rings, but background electrons from residual gas ionization can pose a limit in a less clean vacuum environment. An alternative configuration of the device based on the separation of the jet material ions from the background is suggested and analyzed. The technical feasibility for the SNS MEBT parameters is demonstrated.

A system has been developed for attachment to sediment corers to obtain an in situ acoustic velocity profile during a coring operation. The system uses two electroacoustic transducers mounted in the cutting head of the corer and associated electronics circuitry to measure the travel time of an acoustic pulse traversing the diameter of the sediment core. Laboratory and field tests have been conducted and the results show that the system provides useful information. Acoustic velocity profiles were obtained in the Gulf of Mexico using a piston corer and in shallow coastal waters using a hand corer.

For dynamic three-dimensional (3-D) surface reconstruction of continuously deformed objects, an efficient method employing one fringe pattern is proposed. First, a two-dimensional wavelet transform profilometry (2-D WTP) employing an improved cost function is adopted to obtain the wrapped phase, which has the better noise suppression ability. Then, a new 3-D phase unwrapping algorithm is introduced to obtain the unwrapped phase, which includes four steps. a) A new 3-D residues recognition method is proposed. b) A 3-D branch cut construction algorithm based on an improved GA is proposed. c) A 3-D phase derivative variance quality map is established. d) A 3-D flood filling phase unwrapping algorithm guided by 3-D quality map avoiding 3-D branch cut (3-D FGQAB) is introduced to obtain the unwrapped phase. Simulation and experimental comparisons are carried out, the results show that the proposed method can be applied to dynamic 3-D reconstruction of the continuously deformed objects.

Fringe projection profilometry (FPP) has been widely studied for measurements of three-dimensional (3D) shapes. However, the measurement of moving objects is still a challenging problem associated with commonly used methods. Phase-shifting profilometry (PSP) suffers from motion-induced errors when applied to moving objects, while Fourier transform profilometry (FTP) is sensitive to background light and noise. This paper proposes a novel data fusion approach to improve the measurement of moving objects by alleviating noise-induced errors. Firstly, a set of coarse measurements on the shape of the object are obtained at different time instants by FTP. Then the parameters associated with the motion of the object over these time instants are retrieved from these coarse estimates by applying the iterative closest point (ICP) method. Finally, the parameters are utilized to adaptively fuse the coarse measurements based on their quality. Simulations and experiments verify that the proposed approach can significantly improve the measurement accuracy.