Position Detection System Research Articles

도시형자기부상열차 열차제어시스템 RAMS 분석에 관한 연구

도시형 자기부상열차 실용화사업에 적용된 유도무선루프방식 열차제어시스템에 대하여 최상위 레벨에서 전체 시스템에 대한 시스템 분류, 기능 분석을 시행하고 차상신호설비, 지상신호설비로 나누어 신뢰도, 가용도, 유지보수도 및 안전도를 수식을 통하여 분석한 결과를 제시하였다. RAM 분석은 신뢰도 블록도(RBD)를 각 장치별로 적용하여 시스템 서비스 가용도를 산출하였고, 안전도 분석은 PHA(예비위험원 분석), FMEA (고장모드영향분석), HAZOP을 통한 각각의 정상사상(Top Event)의 FTA(고장트리분석)을 시행하고 그 결과를 제시하여 RAMS 목표 값에 도달함을 수식을 통하여 증명하였다. In this study, Urban maglev is applied to inductive-loop speed and position detection system for the top-level classification system for the entire system, and performed functional analysis On-board signal equipment, Wayside-signal equipment divided by the reliability, availability, maintainability, and safety through analysis of the proposed formula. RDB and by applying a system service for each device was calculated to availability, safety analysis. The PHA, FMEA, HAZOP over the Top Event of the FTA is performed by presenting the results. This also shows approach methods and relative activities for project to accomplish and ensure the system requirements.

Optimized Design of Sun Position Detection Sensor

With the object of optical sensor detects the position of the sun, the working principle of the sun position detection system based on four photosensitive devices was analyzed.The sensitive part of this type of sensors was analyzed with optimization. Silicon photocells were selected as optical elements . The main factors and interactions between them which affect the accuracy of the sensor were analyzed using the idea of orthogonal experiment and related software , the optimal combination for the size of the sensor structure was got.

Modeling and Analysis of a Wavelet Network-Based Optical Sensor for Vibration Monitoring

In this paper, we present a wavelet network (WN)-based optical position sensor for vibration monitoring using a quad-cell photodetector array. The proposed system uses a He-Ne laser source whose Gaussian beam impinges on the photodetector array. The optical power distribution from the photodetectors is acquired and fed to a position detection system, which maps the power distribution to the x-y position of the laser beam center. The position detection system uses a WN for function approximation to yield the correct mapping. The advantage of the WN is its generalization property. The network can be trained using a small size lookup table and, when properly trained, can provide a correct estimate of the laser position even if the power readings were not included in the training set. An accurate theoretical model of the system was derived to simulate the optical power variation as the beam scans the photodetector array. An experimental setup was next developed to validate the theoretical model. The results obtained show the effectiveness of WNs to estimate the laser beam position for the purpose of vibration monitoring.

Research on the Filtering Algorithm in Speed and Position Detection of Maglev Trains

This paper introduces in brief the traction system of a permanent magnet electrodynamic suspension (EDS) train. The synchronous traction mode based on long stators and track cable is described. A speed and position detection system is recommended. It is installed on board and is used as the feedback end. Restricted by the maglev train’s structure, the permanent magnet electrodynamic suspension (EDS) train uses the non-contact method to detect its position. Because of the shake and the track joints, the position signal sent by the position sensor is always aberrant and noisy. To solve this problem, a linear discrete track-differentiator filtering algorithm is proposed. The filtering characters of the track-differentiator (TD) and track-differentiator group are analyzed. The four series of TD are used in the signal processing unit. The result shows that the track-differentiator could have a good effect and make the traction system run normally.

Development of Radio Frequency Identification Textile and Mapmaking System

In this paper, we present a highly accurate position detection system using a textile technique as a useful application of radio frequency identification (RFID) technology. To support this system, we also developed an automatic mapmaking system. Massively distributed RFID tags have the potential for location-aware applications. However, deploying RFID tags and correlating the physical coordinates of each tag identification for mapmaking is relatively expensive and time-consuming. We developed RFID textile and a customized textile inspection machine as an automatic mapmaking system. We examined the feasibility of a tracking system using the RFID textile that was calibrated by the developed mapmaking system. The calibration for a 19-m length of RFID textile, including 1900 RFID tags, was completed within 38 min, and RFID-based tracking system could successfully detect a walking trajectory.

Position Sensing System of Nasogastric Tube Using Long LC Resonated Marker

A position-detecting system made up of a nasogastric tube using a wireless LC resonated magnetic marker has been developed. The marker, consisting of an inductor and a capacitor without battery or electric wires, was installed inside a commercial nasogastric tube. A positioning accuracy within 7.1mm was obtained when the marker inside the tube was parallel translation to 100mm. The marker inside the tube was roughly tracked in the esophagus and trachea of a human model.

라인형 레이저를 이용한 비전기반 차량용 폐오일필터 검출 시스템

There are so many successful applications to image processing systems in industries. In this study we propose a position detection system for used oil filter by using a line laser. We have been done on the development of line laser as interaction devices. A camera captures images of a display surface of a used oil filter and then a laser beam location is extracted from the captured image. This image is processed and used as a cursor position. We also discuss an algorithm that can distinguish the front part and rear part. In particular we present a robust and efficient linear detection algorithm that allows us to use our system under a variety lighting conditions, and allows us to reduce the amount of image parsing required to find a laser position by an order of magnitude.

Position detection and vibration monitoring system using quad-cell optical beam power distribution

In this paper, we study the accuracy of an optical vibration sensing system using Gaussian beam analysis. The proposed optical system uses a He–Ne laser source whose Gaussian beam impinges on a quad-cell photodetector array. The normalized optical power for each cell is obtained through numerical simulation based on the well-known Gaussian beam optics formulation, as the beam scans the plane of the photodetectors due to vibration. The system detection principle lies upon finding a relationship between the power distribution of the quad-cell and the position of the beam centroid, which allows us to identify the characteristics of the vibration applied, such as direction, frequency and strength. The aspects of practical implementation and experimental limitations on the power distribution accuracy are discussed and the discrepancies with the theoretical results are presented.

전방향 위치검출 시스템을 이용한 이동로봇의 주행방법

이동로봇은 고정된 로봇에 비해 작업영역을 확장할 수 있다는 장점이 있다. 하지만 이러한 장점은 센서들을 사용하여 자신의 위치를 추정하거나 로봇이 원하는 목적지를 파악함으로써 얻어질 수 있다. 본 논문은 전방향 위치추정 시스템을 이용한 이동로봇의 주행방법에 대하여 설명하고 있다. 이 시스템은 간단한 위치검출 장치를 이용하여 간소화된 위치 데이터를 프로세서에 제공한다. 즉, 사용자가 로봇의 도착점을 지시하면 이 시스템이 위치 방향을 실시간으로 비교 분석하여 오차를 보정한다. 이를 위하여 원뿔형 거울과 단일 카메라를 사용하였다. 이 결과, 사용자가 로봇을 움직이기 위해 가리킨 타겟을 찾아내는 영상처리 시간을 줄일 수 있었다. Comparing with fixed-type Robots, Mobile Robots have the advantage of extending their workspaces. But this advantage need some sensors to detect mobile robot's position and find their goal point. This article describe the navigation teaching method of mobile robot using omni-directional position detection system. This system offers the brief position data to a processor with simple devices. In other words, when user points a goal point, this system revise the error by comparing its heading angle and position with the goal. For these processes, this system use a conic mirror and a single camera. As a result, this system reduce the image processing time to search the target for mobile robot navigation ordered by user.

Mie scattering distinguishes the topological charge of an optical vortex: a homage to Gustav Mie

One century after Mie's original paper, Mie scattering is still a fertile field of scientific endeavor. We show that the Mie scattering distinguishes the topological charge of light beams with phase dislocations. We experimentally and numerically study the scattering of highly focused Laguerre–Gaussian beams by dielectric and metal spheres, and show that the scattered field is sensitive to the modulus and to the sign of the topological charge. The implications for position detection systems are also discussed.

1P1-F19 色素増感素子アレイを用いた装着型視線検出システムの開発

Detection of the line-of-sight (LOS) has various applications, such as communication technology and welfare field. To realize such applications, there is strong demand for an LOS detection system that does not restrict users' activities and inflicts no mental stress. In this paper, we propose a novel wearable pupil position detection system, featuring minimum disturbance to users, both physically and mentally, via the use of dye-sensitized photovoltaic devices. These devices are transparent and generate voltage according to the incident light intensity. Arraying the devices on eyeglasses, this system detects the difference in the reflection light from the pupil and the white of the eye and hence determines the position of the pupil.

Equipment and transducer-independent 3D ultrasound in the maxillofacial area

The use of a new 3D ultrasound system should reduce the drawbacks of former 3D workstations (long image generation time, limited use due to the need for special 3D transducers), so that it is now applicable in daily clinical routine. An ultrasound 3D workstation was used based on a pentium PC platform, employing a magnetoelectronic position detection system for spatial reconstruction of conventional 2D B-scan image sequences. Better assessment of topographico-anatomical spatial relationships was achieved when presenting pathological findings, especially in assessing lymph nodes and salivary stones. Pathological processes in the maxillofacial area occurring during a period of five months were visualised. The method of 3D reconstruction of standard two-dimensional electronic scans, as presented here, is the first method of its kind enabling applicability in daily clinical routine thanks to rapid imaging. The images can be produced with any ultrasound unit or transducer. First clinical results in maxillofacial surgery clearly show improved diagnostic possibilities although there still room for an improvement of the image quality. The possibility of semi-automatic exact volumetry appears meaningful especially in the investigation of lymph nodes. Integration of colour duplex sonography will further enhance the diagnostic value of this method.

536 色素増感素子を用いた装着型瞳位置検出デバイス(T04 MEMS技術を用いたヒューマンインターフェース,大会テーマセッション,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

536 色素増感素子を用いた装着型瞳位置検出デバイス(T04 MEMS技術を用いたヒューマンインターフェース,大会テーマセッション,21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

Wearable pupil position detection system utilizing dye-sensitized photovoltaic devices

Detection of the line-of-sight (LOS) has a variety of applications, such as communication tools for elderly or disabled people, assisting drivers, and effective location of traffic signs. To realize such promising applications, there is strong demand for an LOS detection system that does not restrict users’ activities and inflicts no mental stress. The LOS can be obtained by combining the directions of the face and eyes, respectively, where the detection of location and motion of the pupils is a critical technology. In this paper, we propose a novel wearable pupil position detection system, featuring minimum disturbance to users, both physically and mentally, via the use of dye-sensitized photovoltaic devices. These latter are transparent and generate voltage according to the incident light intensity. Arraying the devices on wearable eyeglasses, this system detects the difference in the reflection light from the pupil and the white of the eye and hence determines the position of the pupil. It is wearable as an eyeglass, meaning it does not disturb users’ activities or eyesight. More importantly, it involves minimal physical and psychological stress. We fabricated the photovoltaic device and demonstrated their feasibility to determine the location of the pupil. We found it possible to meet the required reaction time of 100ms by reducing the size of the device and to improve the accuracy of pupil location detection by arraying the devices.

A simple X-ray position detection system based on a MHSP

A simple system for position detection based on a Micro-Hole and Strip Plate (MHSP) using a resistive charge division method was implemented. A thin resistive layer of about 100 Ω between each strip (top surface) and between each anode strip (bottom surface) allows us to obtain the actual position in both orthogonal directions. The readout electronics uses only two preamplifiers, a sum and a divider circuit to calculate the interaction point, in each dimension. For a detector filled with 1 atm of pure xenon, position resolutions of less than 300 μm (FWHM) were achieved using 5.9 keV X-rays, for a signal-to-noise ratio (SNR) of 30. For these conditions, a detector gain of about 10 4 and an energy resolution of about 15% were obtained.

ディジタルスチルカメラにおける新フォーカス原点検出システムの開発

Digital still cameras require both accuracy with the focal function and quick response. We developed a new focus home position detection system that consists of two algorithms. The first, the home position judging algorithm, detects the home position as the level of the photo sensor changes, and it memorizes the excitation position of the stepping motor for the lens drive. When it detects the home position again, it judges the level change of a photo sensor in the excitation position distant from the memorized excitation position by a half of an excitation pattern cycle. It then reproduces the original home position. The second algorithm, the temperature compensation algorithm, makes the memorized excitation position follow the temperature change. The new system cancels out any home position error by the camera posture difference and improves the initialization time (by about 0.3 seconds). We introduced this system into our camera DMC-LC1.

Training System for Manual Arc Welding by Using Mixed Reality

A simulator for training manual arc welding operation by means of mixed reality technique was proposed and discussed in the previous paper. According to the experimental training results with the simulator in it, most trainees could not gain the skill of electrode tip positioning so well, though they could gain the skill of moving speed and angle control of the electrode. In this research, the authors investigate the reason for the less effectiveness and the solutions. As the results, it is found that in the conventional system, the trainees have difficulty in perception of electrode tip position, because of its inaccurate drawing in the real environmental image and two dimensional visual displaying. To improve the drawing accuracy, the camera for video-see-through HMD is replaced with high resolution ones and the multimarker position detection system is adopted. In addition, a stereo vision HMD with an easy vergence angle adjustment function is adopted to give the trainees three dimensional image. The experiments with the improved simulator show apparent reduction of the position-perception error of electrode tip and effective training.

Two-dimensional position detection system with MEMS accelerometers, readout circuitry, and microprocessor for padless mouse applications

A hybrid two-dimensional position sensing system is designed with microelectromechanical systems (MEMS) for padless mouse applications. The X/Y-axis acceleration of the user's hand movements is measured by two MEMS accelerometer devices. These acceleration values are pulsewidth modulated and converted into (X, Y) coordinates on the screen by integral operations on a microprocessor. The overall system consists of four major components: 1) MEMS accelerometers; 2) CMOS analog readout circuitry; 3) an acceleration magnitude extraction module; and 4) a 16-b RISC microprocessor. Mechanical and analog simulation shows that the designed mouse system can detect acceleration as small as 5.3 mg (g=9.8 m/s/sup 2/) with 100-kHz sampling frequency for low power consumption.

Development of an analog processing circuit for IR-radiation power and noncontact position measurements

An analog circuit which simultaneously performs radiation power and position measurement of an IR-laser spot (wavelength 1.3μm) on a four quadrant photodiode is presented and described. Its main features are 2MHz-bandwidth and low noise (14mVrms) for a nominal working radiation power of 2mW. This circuit has been implemented for the detection stage of an internal IR-laser deflection set-up, used to measure internal temperature gradients and free carrier concentration in vertical power devices. The measurements of the previously mentioned magnitudes inside the drift region of a 600V PT-IGBT are presented under critical operation conditions. This circuit, however, can also be used in other noncontact position and power radiation detection systems that require a high bandwidth and low noise levels. Moreover, the different noise sources along the detecting system have been identified. It is shown that the main contribution to the noise level at the processing circuit output is basically introduced by its second stage (analog divisor), assuring, for a 1mm laser spot centered at the photodetector, a maximum resolution in position measurement below 2μm.

Position-Detecting System Based on the Global Positioning System

The Railway Technical Research Institute has developed a position detection system based on a new Global Positioning System (GPS). This system uses GPS to detect the approximate location of a train and then selects one of three algorithms to process the location data and determine the train's precise location. Running tests performed on the system showed that its position error was less than 4 m. This system has the potential to be used to control the car body tilting of tilt trains accurately and allow them to run at the maximum possible speed through the tight curves typical of the narrow-gage lines found in Japan. In addition, the automatic map created by this system makes it much easier to maintain the accuracy of the onboard database.