12 Shaft encoder is widely used in order to measure rotation angle in automatic system. Commonly used incremental encoder is low cost and has high resolution compared with an absolute encoder. However, it is susceptible to power line noise and failures. Absolute type encoders are generally used in applications where it is difficult to return to their home positions in system failure. Both type encoders use light sources, coding disk, light detectors and signal processing circuits. In order to obtain absolute rotary position, gray code is usually utilized in the code disk. Therefore, the resolution of an absolute encoder is dependent on the space to engrave the code. In this paper moire fringe is used to increase the resolution in addition to the gray code pattern. Since the fringes move nonlinearly as the code disk rotates, the position related with the rotation angle is obtained by a neural network. A prototype encoder is set up and a series of experiments are conducted.

12 A biosensor telemetry system for the on-line remote monitoring of toxic sites is described in this paper. The device is a self-contained field measurement system that employs immobilized luminescent. Vibrio fisheri bacteria to detect airborne contaminants. The presence of toxic chemicals in the air will lead to a measurable decrease in the intensity of light produced by the bacteria population. Both cellular and environmental factors control the level of bioluminescence exhibited by the bacteria. The biological sensing element is placed inside a miniature airflow chamber that houses a light-to-frequency transducer, power supply, and Radio-Frequency (RF) transmitter to convert the intensity of bioluminescence exhibited by the bacteria population into a radio signal that is picked up by a RF receiver at a safe location. The miniature biosensor can be transported to the investigated on either a terrestrial or airborne robotic vehicle. Furthermore, numerous spatially distributed biosensors can be used to both map the extent and the rate-of-change in the dispersion of the hazardous contaminants over a large geographical area.

12 This paper deals with the non-contact optical sensor to measure the shape and the thickness of transparent plates such as glass panel of LCD (Liquid Crystal Display). The conventional methods to obtain the shape or thickness of transparent plates are contact type sensor such as LVDT (Linear Variable Differential Transformer). Due to the contact between the tip of the sensor and the surface of objects, the tip is abraded. In addition the casting glass under high temperature results in extending the size of sensor body. The accuracy of the sensor is degraded due to these reasons. In this paper, to overcome these problems, we proposed a low cost non-contact optical sensor that is composed of a hologram laser unit used for optical pickup of CD player and a plastic lens. To evaluate the performance of the proposed optical sensor, a series of experiments were performed for various measurement conditions. Based upon observation of the experimental results, the proposed sensor shows a good performance in measuring the shape of transparent plates.

12 This paper presents a vision processing scheme to automatic weld joint tracking in robotic arc welding process. Particular attention is concentrated on its robustness against various optical disturbances, such as arc glares and weld spatters radiating from the melted weld pool. Underlying the developed vision processing is a kind of model-based pattern searching, which is necessarily accompanied by two separate stages of modeling and tracking. In the modeling stage, a syntactic approach is adopted to identify unknown weld joint structure. The joint profile identified in the modeling stage is used as a starting point for successive tracking of variations in the geometry of weld joint during welding, which is automatically achieved by an active contour model technology following feature- based template matching. The performance of the developed scheme is investigated through a series of practical welding experiments.

12 In this paper an inspection system for both weld quality and chamfer quality is presented which is a 3D laser vision system using principles of optical triangulation, and is composed of sensor head and controller. Sensor head includes laser diode, micro CCD camera, filter and some mirrors. This system can be used in welding bead inspection (including undercut) and chamfer inspection as well. Compared with conventional inspection method, it is much more convenient to use and the inspection time is to be greatly shortened. Data saved in PC can be used for statistics afterwards. This system has been being used in Koje Shipyard or Samsung Heavy Industries and the need is being increased.

12 Ever since surface-mounting technology for printed circuit board (PCB) assembly processes has been developed, electrical products continuously tend toward the miniaturization of components, with denser packing of its boards. With the increasing necessity for reliable PCB product, there has been a considerable demand for high speed, high precision vision system to place the electric parts on PCB automatically. To recognize the electric parts with high accuracy and reliability, illumination condition is instrumental to acquisition of part images. In this paper, a versatile lighting is developed which utilizes three different types of illuminating methods: direct, indirect, and back-light illumination.

12 This paper shows the mathematical expression of the light such as the extinction curve in the optical fields of system using AO deflector, and the axial/lateral response experimentally when the error sources change. We propose the progressive methods for the rejection of image extinction as the following. At first, for having the corrected image, small spot and long scan range, this paper shows that the optimal design having the multi-objects can be used by choosing the unitary lens device in confocal scanning microscopy. At second, in order to compensate for the intensity cancellation at the end profile that may be the cause of waviness for the optical image, this paper shows that it is efficient to schedule the frequency of scan. According to characteristics of the extinction curve and axial/lateral response having the error property, we can define the frequency and sensitivity of as their robustness.

12 Current technological development toward miniaturization requires smaller components. These components usually generate complex multi-DOF motions other than simple 1-DOF mission. Therefore it is essential to develop measurement methodology for 6-DOF motions. In this paper, a new 6-DOF measurement system for milli-structure is presented. This methodology basically employs the Optical Beam Deflection Method with a diffraction grating. A laser beam is emitted toward the diffraction grating which could be attached on the surface of a milli-structure and the incident ray is diffracted in several directions. Among these diffracted beams, 0^th and +/- 1^th order diffracted rays are detected by 4 Quadrant Photodiodes. From coordinate values from each detector, we can get information for 6-DOF motions with linearization method. Required resolutions for milli- structure measurement are sub-micrometer in translation and arcsec in rotation. Experimental results indicate that proposed system has possibility to satisfy this requirement. This method can be applied to measurement of various applications such as arm head of HDD, micro positioning stages.

12 In this paper, a new measuring system is proposed which can measure 6-DOF motion of rigid bodies. Its measurement principle is based on detection of laser beam reflected from a specially fabricated mirror whose shape is a triangular pyramid having an equilateral cross-sectional shape. The 3- facet mirror is mounted on the object whose 6-DOF displacement is to be measured. The measurement is operated by a laser-based optical system composed of a 3-facet mirror, a laser source, three position-sensitive detectors (PSD). In the sensor system, three PSDs are located at three corner points of a triangular formation, which is an equilateral triangular formation lying parallel to the reference plane. From this arrangement, 6-DOF displacement of any object can be simply determined. In this paper, we model the relationship between the 6-DOF displacement of the object and the outputs of three PSDs. A series of experiments is performed to demonstrate the effectiveness of the proposed method. The experimental results show that the proposed sensing system can be an effective means of obtaining 3D position and orientation of arbitrary objects.

12 In manufacturing a rotating-analyzer ellipsometer, error sources and calibration methods are discussed. It is important to get rid of external noise for measurement of high thickness resolution and accurate optical constant and this means that the precision of system above all is important to develop the ellipsometer. Therefore the precision design and error calibration of the optical components in ellipsometer are inevitable. We propose a PSA (polarizer-specimen-analyzer) system to manufacture a rotating-analyzer ellipsometer.

12 The demand to provide greater flexibility in surface- geometry measurement of free-form objects, has led to range sensors which are permitted continuous free motion. However, most devices employ mechanical linkages instrumented with position sensors, or optical or magnetic tracking sensors to determine the position and orientation of the moving range- sensor head. These additional sensors limit the working volume, impede the free movement of the range sensor, or restrict the material allowed in the work environment. This paper presents a method of surface-geometry measurement by a laser-camera range sensor head, which is permitted continuous motion in space, without the need to track its position and orientation by additional sensors.

12 Many methods have been proposed for range finding systems to know the distance of the targets. We try to capture profiles of objects in addition to the distance of objects using optical principle. When a grating pattern is projected on to the object to be measured, the projected pattern is sharply observed on a focused plane. And the pattern blurs due to defocusing except on this focused plane. We detect contrast variation of the projected grating pattern and calculate the distance to the object and captures its shapes at the same time. This method features in using merely one optical axis in range finding system.

12 Heterodyne interferometry is a powerful tool for shape measurement. However, to the present day there are only a few papers devoted to full field, time dependent heterodyne interferometry. Most of known solutions are based on the point measurement, and the shape is obtained by scanning in the examined area. In this paper a full field heterodyne system using the fringe projection principle and fast framing DALSA CA-D1 CCD camera is proposed and discussed. Due to frequency shift between interfering beams the interference pattern is traveling over the object surface and allows heterodyne registration. The use of a fast camera is a certain approximation of classical heterodyning.

12 In this paper, we designed and made a solid immersion lens (SIL) microscope using SIL (diameter equals 1 mm, refractive index n equals 1.83). Through the real experiment, we obtained the scanned-surface image of 700 nm and 300 nm standard specimens using SIL effect (compared with it's SEM scanning picture) an analyzed the result and error of image and system. According to this paper we can assure the capability of SIL microscope and possibility of the development of high-area density, large-capacity data storage device.

12 Novel precision mechanical design for ellipsometer is developed. To develop several properties of precision ellipsometer, the kinematic coupling is used at specimen stage and connecting parts between mainframe and analyzer unit, and connecting part between mainframe and polarizer unit. Homogeneous transformation matrix describes all ellipsometer components and the process of light transmitting through ellipsometer components. Geometrical error analysis is performed in order to minimize the incident alignment errors. As a result of that, the rotational error of light source is most dominant on the error of detected signal. The error bound is +/- 0.08 degree(s) for light source. The translational errors of ellipsometer components don't affect the detected signals. We manufactured a precision ellipsometer using the above- analyzed results and kinematic coupling principle. The manufactured ellipsometer has many good properties, such as precise alignment of incident angle and low manufacturing cost and so forth.

12 As the pressure increases to deliver vision products with faster speed while inspection higher resolution at lower cost, the area scanning vision inspection system can be one of the good solutions. To inspect large area with high resolution, the conventional vision system requires moving either camera or the target, therefore, the system suffers low speed and high cost due to the requirements of mechanical moving system or higher resolution camera. Because there are only tiny mirror angle movements required to change the field of view, the XY mirror controlled area scanning vision system is able to capture random area images with high speed. Elimination of external precise moving mechanism is another benefit of the mirror control. The image distortion due to the lens and the mirror system shall be automatically compensated right after each image captured so that the absolute coordination can be calculated in real- time. Motorized focusing system is used for the large area inspection, so that the proper focusing achieved for the variable working distance between lens and targets by the synchronization to the mirror scanning system. By using XY mirror controlled area scanning vision inspection system, fast and economic system can be integrated while no vibration induced and smaller space required. This paper describes the principle of the area scanning method, optical effects of the scanning, position calibration method, inspection flows and some of implementation results.

12 In this paper, analytical study is performed to reduce residual vibration in seeking motion of optical pick-up. The conditions for acceleration and deceleration time in trapezoidal velocity profile to reduce residual vibration are derived for undamped system. To verify the validity of the conditions, two example studies are carried out. Numerical and experimental implementations for flexible arm system show that residual vibration is effectively reduced by calculated velocity profile. In addition, simulation study for optical pick-up reveals that the conditions for undamped case can be applied to obtain velocity profile with minimum residual energy in damped vibration system by changing natural frequency to resonance frequency.

12 A novel system for depth estimation is proposed with the use of Symbiotic Genetic Algorithms for the continuous problem of disparity surface approximation. The approach is based on the decomposition of the entire surface to very small non- overlapping patches described by low order bivariate polynomials and the use of symbiotic optimization to enforce smoothness at the boundaries of these patches, so that the entire surface can be approximated in a smooth piecewise fashion by functionals of local support. Such optimization is amenable to a massive parallel implementation, since each patch is optimized by a different execution unit and each unit communicates through its cost function only with its four-connected neighbors. The method makes use of various existing crossover and mutation schemes for real-valued chromosome representations and a new problem-specific mechanism for generating and hybridizing the initial populations. The proposed multi-objective cost function enforces photometric similarity and smoothness between the patch boundaries at a local scale, which in the long term give rise to a globally smooth disparity surface.

12 Inspection and shape measurement of 3D objects are widely needed in industries for quality monitoring and control. A number of visual or optical technologies have been successfully applied to measure 3D surfaces. However, those conventional visual or optical methods have inherent shortcomings, which are occlusion problem and variant surface reflection problem. X-ray vision system can be a good solution to these conventional problems, since we can extract the volume information including both the surface geometry and the inner structure of the object. In the x-ray system, the surface condition of an object, whether it is lambertian or specular, does not affect the inherent characteristics of its x-ray images. In this paper, we propose a 3D x-ray imaging method to reconstruct a 3D structure of an object out of 2D x-ray image sets.

12 This paper presents a robotic architecture that facilitates semi-automatic teleoperation of a dual-arm manipulator system. The architecture is built upon reactive behavior agents tightly coupling sensing and action, where emergent behaviors correlate human intervention with sensor-based autonomous operation. Reactive agents are devised for perceptual and motor behaviors, and a structured light system is adopted to provide a visual reference to both behavioral agents and the human operator. The technical feasibility of the robotic behaviors is evaluated through simulation of the collaborative motion of a dual-arm manipulator. The presented sensor based semi-automatic teleoperation may improve human perception and simplify human action, and thus improve the efficiency and precision of teleoperation.

12 This paper deals with an image sensor system and its position estimation algorithm for autonomous duct cleaning and inspection mobile robots. For the real application, a hierarchical control structure that consists of robot motion controller and image sensor system is designed considering the efficient and autonomous motion behaviors in narrow space such as air ducts. The sensor's system consists of a CCD camera and two laser sources to generate slit beams. The image of the structured lights is used for calculating the geometric parameters of the air ducts which are usually designed with a rectangular section. With the acquired 3D information about the environment, the mobile robot with two differential driving wheels is able to autonomously navigates along the duct path without any human intervention. For real time navigation, the relative position estimation of the robot are performed from 3D image reconstructed by the sensor system. The calibration and image processing methods used for the sensor system are presented with the experimental data. The experimental results show the possibility of the sensor based navigation which is important for effective duct cleaning by small mobile robots.

12 Optically driven small machines have such features as easily miniaturized in fabrication and as controlled by optical energy supplied remotely in wireless. We report on an optically controlled machine which moves like a caterpillar on the basis of optomechatronic principle. This miniaturized machine consists of two parts; a body made of shape memory alloys and springs and feet made of a magnet, a temperature- sensitive ferrite. The feet can hold the steel-made floor using magnetic force balance caused by projected beam, and the body repeats expansion and contraction using deformation of shape memory alloys caused by switching of projected beam. A prototype is fabricated in trial with a size of 35 mm X 12 mm. As an experimental result, it proved that they could move at the speed of 8.7 mm per cycle on a ceiling as well as a horizontal steel floor and it could ascend a slope as steep as 50 degree.

12 The main purpose of this paper is to present the Cellular Neural Network (CNN) Paradigm as a powerful strategy to design and to implement in hardware efficient locomotion control techniques. A gallery of biologically inspired walking robots are presented. Moreover, the availability of efficient distributed control structures needs a sensing capability of the same efficiency. Therefore the sensing stage is performed by using once again the CNN paradigm, but used as fast image processors. The strategy is supported by the fact that CNN devices with on-chip optical sensors are currently being tested and will be soon available. In such a way, images are acquired by a video camera with a CNN image processing device, able to extract the key features. These ones represent the `command' to take on the right locomotion pattern. Since all the methodology is realized by using analog processors, the whole strategy represents a real breakthrough in the smart sensing and control field.