Portable Navigation System Research Articles

Usefulness of an accelerometer-based portable navigation system in total knee arthroplasty.

The aim of this study was to evaluate the effects of using a portable, accelerometer-based surgical navigation system (KneeAlign2) in total knee arthroplasty (TKA) on the alignment of the femoral component, and blood loss. A total of 241 consecutive patients with primary osteoarthritis of the knee were enrolled in this prospective, randomised controlled study. There were 207 women and 34 men. The mean age of the patients was 74.0 years (57 to 89). The KneeAlign2 system was used for distal femoral resection in 121 patients (KA2 group) and a conventional intramedullary femoral guide was used in 120 patients (IM group). One patient (0.8%) in the KA2 group and 19 in the IM group had an alignment which was > 3° away from the neutral mechanical axis (p < 0.01). The mean deviation from neutral alignment was 1.01° (standard deviation (sd) 1.0°) in the KA2 group and 1.93° (sd 1.7°) in the IM group (p < 0.01). Blood loss was significantly less in the KA2 group compared with the IM group (784 ml (sd 357) versus 1071 ml (sd 310), p < 0.001). The KneeAlign2 system provides a technically straightforward method for identifying the femoral head and performing an accurate distal femoral resection at TKA with significantly less blood loss compared with a conventional intramedullary guide. Cite this article: Bone Joint J 2017;99-B:1047-52.

TKAにおけるKnee Align 2を用いた大腿骨コンポーネント設置精度の検討

TKAにおけるKnee Align 2を用いた大腿骨コンポーネント設置精度の検討

Evaluation of femoral head movement in total knee arthroplasty using portable navigation system

Evaluation of femoral head movement in total knee arthroplasty using portable navigation system

시각 장애인을 위한 Navigation System의 설계 및 구현

도시의 급격한 발전으로 공사가 증가하게 되고 이동 차량 또한 증가 하게 된다. 이는 자연히 시각 장애인들의 보행을 점점 더 어렵게 만든다. 이러한 어려움을 해결하고자 Android 기반의 Portable Navigation System을 도입하여 시각 장애인의 보행을 돕고, 서비스 센터에서 시각 장애인의 이동을 실시간으로 모니터링 하여서 시각 장애인의 보행에 도움을 주고자 한다. 노인이 서비스 센터에 배치되어 노인 인구 증가 문제의 해소 방안도 제공한다. 시각 장애인이 소지하고 다닐 수 있는 형태의 Navigation System은 GPS, Camera, Audio, wifi를 장착하고 있다. GPS위치 정보와 Camera 영상 정보를 실시간으로 wifi망을 이용해 서비스 센터로 전송을 하여 주도록 설계 하였다. 서비스 센터에서 시각 장애인의 GPS Location 정보를 바탕으로 그 위치를 지도에 표시하고, Camera 영상 정보로 시각 장애인이 바라보고 있는 곳의 상황을 모니터링 하며, Audio를 통해, 실시간으로 대화를 통해서 길안내 해주는 Navigation System이다. In the rapid growth of cities, road has heavy traffic and many buildings are under constructions. These kinds of environments make more difficulty for a person who is visually handicapped to walk comfortable. To alleviate the problem, we introduce Navigation System to help walking for Visually Impaired Person. It follows, service center give instant real time monitoring to visually impaired person for their convenient by this system. This Navigation System has GPS, Camera, Audio and Wi-Fi(wireless fidelity) available. It means that GPS location and Camera image information can be sent to service center by Wi-Fi network. To be specific, transmitted GPS location information enables service center to figure out the visually impaired person's whereabouts and mark the location on the map. By delivered Camera image information, service center monitors the visually impaired person's view. Also, they can offer live guidance to visually impaired person by equipped Audio with live talking. To sum up, Android based Portable Navigation System is a specialized navigation system that gives practical effect to realize more comfortable walking for visually impaired person.

Smart Portable Navigation System 개발 및 1:N 서비스 구현

기존의 개발된 시각 장애인을 위한 길 안내 서비스를 위한 보조기구는 지팡이에 장착된 RFID 태그를 이용, 표지블록과 RF통신을 하는 정도의 간단한 보행 안내 서비스였습니다. 이는 RFID의 리더기의 인식거리가 짧고, 명확한 장애물의 위치, 크기 및 형태를 판단 할 수 없다. 이에 위험 사항이나 길안내 중 경로 이탈 발생 시 대책방안이 시급히 필요하다. 오늘 날 스마트 디바이스 개발로 인해 사용자들에게 다양한 혜택과 편리성을 제공 하고 있다. 이에 안드로이드 플랫폼 Client 와 Server(PC)간의 소켓 스트림을 이용, 실시간 영상정보와 음성, 위치정보를 전송하여 시각장애인의 위험 상황에 즉각적인 조치를 취할 수 있는 시스템 및 1:N 서비스를 구현하고자 한다. The current Navigation System for the Visually Impaired Person has a short and limited communication distance and can't receive enough information from Visually Impaired Person to assist directly. In addition, because the path is dangerous and incomplete for the Visually Impaired Person, moving with White Stick is still inconvenient and dangerous. To solve this problem we implement communication that can send and receive video, voice, location information between the Visually Impaired Person's Smart Portable Navigation System Development and assistant's PC.

State of the art review on walking support system for visually impaired people

The technology for terrain detection and walking support system for blind people has rapidly been improved the last couple of decades but to assist visually impaired people may have started long ago. Currently, a variety of portable or wearable navigation system is available in the market to help the blind for navigating their way in his local or remote area. The focused category in this work can be subgroups as electronic travel aids (ETAs), electronic orientation aids (EOAs) and position locator devices (PLDs). However, we will focus mainly on electronic travel aids (ETAs). This paper presents a comparative survey among the various portable or wearable walking support systems as well as informative description (a subcategory of ETAs or early stages of ETAs) with its working principal advantages and disadvantages so that the researchers can easily get the current stage of assisting blind technology along with the requirement for optimising the design of walking support system for its users.

Comparison of portable and onboard navigation system for the effects in real driving

Navigation systems are very useful and popular tools which display a user’s location and make use of graphics, text and voice information to guide him to a predetermined destination. Recently, some researches had revealed that drivers choose to receive driving directions using portable devices owing to their price and convenience. This study aimed to survey whether the driving efficiency and controlling are different as using portable and onboard navigation systems. A smartphone (2.7″ screen) and driving support system we instructed (8.9″ display interface) were adopted as the portable and onboard navigation systems respectively. Thirty subjects were paid to participate in this study, and field experiments were executed in urban and rural environments. Participants were randomly divided into two groups with equal numbers and drove according to instructions provided by one of these systems. The results indicated that the performance of drivers using the portable navigation system is better than that of the onboard one, in terms of efficiency and car handling, both in the urban and rural environments, despite the fact that the display screen of the phone is so small.

Field Comparison of Driving Performance Using a Portable Navigation System

Recent work has revealed that increasing numbers of drivers now receive driving instructions using a portable navigation system. A 2×2×2 (position×display decrease mode×voice) factorial experiment was executed to compare driving performance when using a portable navigation system (PNS). Thirty-two subjects were paid to participate in this field study, and a smart phone was adopted as the portable navigation device. The results indicated that drivers using the PNS under the conditions up position and with voice instruction performed better in terms of trip duration, mean speed, and the standard deviation of speed.

Civilian Vehicle Navigation: Required Alignment of the Inertial Sensors for Acceptable Navigation Accuracies

A vital necessity for any kind of inertial navigation system (INS) is the alignment of its axis with the vehicle body frame (VBF). Civilian vehicle navigation has strict requirements with respect to cost, size, reliability, and ease of implementation of the system. Microelectromechanical system (MEMS) inertial sensors have satisfied the cost and size requirements for civilian vehicle navigation; however, reliability and ease of implementation of these low-cost and miniaturized navigation systems are still parts of major research and investigation. This paper focuses on an important aspect of the ease of implementation for inertial sensors. From a civilian user perspective, accurately aligning the inertial system with respect to the vehicle, before every use, is not a desirable quality for a portable navigation system. In addition, it is not realistic to assume that even a careful user can achieve good alignment accuracy of the system. The purpose of this paper is to investigate the effects of misalignment errors that will produce errors in initial alignment and affect the navigation accuracy for two different inertial systems. The inertial systems are classified according to the number of sensors used in the system. The first system consists of three gyros and three accelerometers [full inertial measurement unit (IMU)], whereas the second system only has one gyro and two horizontal accelerometers (partial IMU).

Incorporating e-Technology to Advantage in a Greener Taxi Industry and its Impact on Driving Performance and Safety

New technologies, especially advances in telecommunications, have had profound impacts on everyday life and brought even greater changes to some business models. Taxis represent one of the major modes of transportation in urban areas but they face a number of problems, including their environmental impacts. The status of the taxi industry in Taiwan is revealed and analyzed in this study. A new business model for the extensive and popular use of smart phones is proposed. However, it is important to know whether their use is both effective and safe. Two field experiments were executed to examine the effects on taxi drivers of using a navigation system installed in a GPS PDA phone. The results revealed that the efficiency of drivers using such a portable navigation system was better than those relying on paper maps in unfamiliar urban areas. Furthermore, performance in terms of safety was also better than those who used an on-board navigation system. In summary, incorporating e-technology can promote a taxi company's competitiveness and a driver's performance and safety as well as offer environmental benefits.

Effects of using a portable navigation system and paper map in real driving

Navigation systems are very useful tools because they display a user's location and guide them to a destination using graphics, text and voice information. Recent work has revealed that millions of consumers received driving directions using their cell phone or PDA. This present work aimed to explore whether the efficiency to destination and driver behavior were distinguishable when using a portable navigation system compared to a paper map. Thirty-two subjects were paid to participate in this research, with field experiments being carried out in both urban and rural environments. A smart phone was adopted as the portable navigation system in the study. The results revealed that the drivers performed better when using a portable navigation system compared to those using a paper map, in terms of efficiency to destination and driving performance. In addition, drivers could save time and gasoline using a portable navigation system when in an unfamiliar region, and driving performance may be safer, despite the fact that the display screen of the phone is small.

High Sensitivity Micro-fabricated Fluxgate Sensor with a Racetrack Shaped Magnetic Core

We present a micro fluxgate magnetic sensor having solenoid coils and racetrack shaped magnetic core, which was designed to decrease the .operating power and magnetic flux leakage. Electroplated copper coils of <TEX>$6\;{\mu}m$</TEX> thickness and the core of <TEX>$3\;{\mu}m$</TEX> thickness were separated by benzocyclobutane (BCB) having a high insulation and good planarization characters. Permalloy <TEX>$(Ni_{0.8}Fe_{0.2})$</TEX> as a magnetic core was also electroplated under 2000 gauss to induce the magnetic anisotropy. The core had the high DC effective permeability of <TEX>$\~1,300$</TEX> and coercive field of <TEX>$\~0.1$</TEX> Oe. The fabricated fluxgate sensor had the very small actual size of <TEX>$3.0\times1.7\;mm^2$</TEX>. The fluxgate sensor with a racetrack shaped core had the high sensitivity .of <TEX>$\~350$</TEX> V/T at excitation condition of 3 <TEX>$V_{P-P}$</TEX> and 2 MHz square wave. When two fluxgates were perpendicularly aligned in terrestrial field, their two-axis output signals were very useful to commercialize an electronic azimuth compass for the portable navigation system.

An HSGPS, inertial and map-matching integrated portable vehicular navigation system for uninterrupted real-time vehicular navigation

Robust real-time vehicle positioning is a critical requirement for many in-vehicle technologies. However, no standalone positioning system is capable of providing uninterrupted and accurate vehicular navigation data in all environments that a vehicle could encounter. This paper presents a portable vehicular navigation system that combines high-sensitivity GPS, inertial sensors and map-matching techniques to provide uninterrupted vehicular navigation information in even the harshest environments for individual sensor technologies. This system eliminates the need for complex initialisation routines required for high-end inertial sensors, making it a truly portable system. The map-matching component establishes a link between the vehicle and spatial information useful for many more in-vehicle technologies such as route guidance and location-based services. The system performance is evaluated and presented in an urban centre with extreme levels of GPS signal degradation.

携帯型歩行者ナビゲーションシステムとその評価

携帯型歩行者ナビゲーションシステムとその評価

ヒューマンインフォメーション 画像処理を用いた携帯型視覚障害者歩行支援システムの検討

This paper describes a portable traveling support system that uses image processing to aid the visually impaired. We have already previously proposed a portable navigation system for the visually impaired. However. there are some places where this system is unable to provide the proper guidance. Since the travel direction of the user of this system is measured by a terrestrial magnetic sensor. there is a possibility that the wrong direction is measured. due to a distortion of the terrestrial magnetism caused by vehicles, etc. Road markings. e.g., pedestrian crossings, white lines of roadways. are reliable information that can be used to measure the correct direction. Furthermore, landmarks, e.g., electric poles. traffic-control signs and postal boxes. are also useful for a traveler to confirm his position. Therefore, we applied image processing to our portable navigation system to make it more reliable.

Applications of Personal Computers to Marine Navigation and Surveying on the Gulf Coast

A low cost, portable marine navigation and survey system called MultiNav was developed using commercially available personal computers, peripherals and standard software operating systems. The MultiNav system was tested and compared with Integrated Data System's Hyperange as a reference system. A marine survey test was conducted onboard a survey vessel in the Gulf of Mexico to compare the personal computers as a precision navigation and data collection system conventionally performed by larger and/or more expensive equipment. This paper describes the MultiNav system hardware, software and functional capabilities. It also describes the survey test parameters and compares the test results of the two systems. Various statistical performance parameters are presented on the systems tested. The results of this test indicate that a personal computer using commercially available peripherals and standard software offers great promise of replacing larger and more expensive computing equipment.