المؤلفون: Wei, Dongyan¹ (AUTHOR) weidy@aircas.ac.cn, Huang, Lichen^1,2 (AUTHOR) huanglichen17@mails.ucas.ac.cn, Ji, Xinchun^1,2 (AUTHOR), Li, Wen^1,2 (AUTHOR), Lu, Yi^1,2 (AUTHOR), Yuan, Hong¹ (AUTHOR)

المصدر: Sensors (14248220). 12/15/2019, Vol. 19 Issue 24, p5410. 1p.

مصطلحات موضوعية: *GLOBAL Positioning System

مستخلص: Magnetic navigation is a promising positioning technique for scenarios where a global navigation satellite system (GNSS) is unavailable, such as for underwater submarines and aircraft in space. For ground scenarios, it faces more challenges, since the magnetic distribution suffers interference from surrounding objects such as buildings, bridges, and vehicles. It is natural to think how feasible it is to apply magnetic matching positioning to vehicles. In this paper, a theoretic distribution model is proposed to analyze the magnetic field around objects such as buildings, bridges, and vehicles. According to the experiments, it is shown that the proposed model matches the experimental data well. In addition, a comprehensive indicator metric is defined in this paper to describe the feasibility of the magnetic matching method based on the statistical characteristics of magnetic maps. The best length of matching window, anti-noise performance, and pre-comparison of positioning accuracy in different regions can be easily derived using the proposed comprehensive indicator metric. Finally, the metric is verified through a drive test using different building densities. [ABSTRACT FROM AUTHOR]

المؤلفون: Zhang, Wenchao^1,2 (AUTHOR) yuanhong@aircas.ac.cn, Wei, Dongyan² (AUTHOR) zhangwenchao@aoe.ac.cn, Yuan, Hong² (AUTHOR)

المصدر: Sensors (14248220). Sep2019, Vol. 19 Issue 18, p3962-3962. 1p.

مصطلحات موضوعية: *INERTIAL navigation systems, *KALMAN filtering, *DRIVER assistance systems

مستخلص: The zero-velocity update (ZUPT)-aided extended Kalman filter (EKF) is commonly used in the traditional inertial navigation system (INS)-based foot-mounted pedestrian dead reckoning (PDR) system, which can effectively suppress the error growth of the inertial-based pedestrian navigation systems. However, in the realistic test, the system still often suffers from drift, which is commonly caused by two reasons: failed detection of the stationary phase in the dynamic pedestrian gait and heading drift, which is a poorly observable variable of the ZUPT method. In this paper, firstly, in order to improve the initial heading alignment accuracy, a novel method to calibrate the PDR system's initial absolute heading is proposed which is based on the geometric method. By using a calibration line rather than only using the heading of the starting point, the method can calibrate the initial heading of the PDR system more accurately. Secondly, for the problem of failed detection of the stationary phase in the dynamic pedestrian gait, a novel stationary phase detection method is proposed, which is based on foot motion periodicity rather than the threshold comparison principle in the traditional method. In an experiment, we found that the zero-speed state points always occur around the minimum value of the stationary detector in each gait cycle. By taking the minimum value in each gait cycle as the zero-speed state point, it can effectively reduce the failed detection of the zero-speed interval. At last, in order to reduce the heading drifts during walking over time, a new motion constraint method is exploited based on the range constraint principle. During pedestrian walking, the distance between the foot position estimates of the current moment and the previous stationary period is within the maximum stride length. Once the distance is greater than the maximum stride length, the constraint method is used to confine the current estimated foot position to the sphere of the maximum stride length relative to the previous stationary foot position. Finally, the effectiveness of all proposed methods is verified by the experiments. [ABSTRACT FROM AUTHOR]

المؤلفون: Potorti, Francesco, Park, Sangjoon, Crivello, Antonino, Palumbo, Filippo, Girolami, Michele, Barsocchi, Paolo, Lee, Soyeon, Torres-Sospedra, Joaquin, Ruiz, Antonio Ramon Jimenez, Perez-Navarro, Antoni, Mendoza-Silva, German Martin, Seco, Fernando, Ortiz, Miguel, Perul, Johan, Renaudin, Valerie, Kang, Hyunwoong, Park, Soyoung, Lee, Jae Hong, Park, Chan Gook, Ha, Jisu, Han, Jaeseung, Park, Changjun, Kim, Keunhye, Lee, Yonghyun, Gye, Seunghun, Lee, Keumryeol, Kim, Eunjee, Choi, Jeong-Sik, Choi, Yang-Seok, Talwar, Shilpa, Cho, Seong Yun, Ben-Moshe, Boaz, Scherbakov, Alex, Antsfeld, Leonid, Sansano-Sansano, Emilio, Chidlovskii, Boris, Kronenwett, Nikolai, Prophet, Silvia, Landay, Yael, Marbel, Revital, Zheng, Lingxiang, Peng, Ao, Lin, Zhichao, Wu, Bang, Ma, Chengqi, Poslad, Stefan, Selviah, David R., Wu, Wei, Ma, Zixiang, Zhang, Wenchao, Wei, Dongyan, Yuan, Hong, Jiang, Jun-Bang, Huang, Shao-Yung, Liu, Jing-Wen, Su, Kuan-Wu, Leu, Jenq-Shiou, Nishiguchi, Kazuki, Bousselham, Walid, Uchiyama, Hideaki, Thomas, Diego, Shimada, Atsushi, Taniguchi, Rin-Ichiro, Puschel, Vicente Cortes, Poulsen, Tomas Lungenstrass, Ashraf, Imran, Lee, Chanseok, Ali, Muhammad Usman, Im, Yeongjun, Kim, Gunzung, Eom, Jeongsook, Hur, Soojung, Park, Yongwan, Opiela, Miroslav, Moreira, Adriano, Nicolau, Maria Joao, Pendao, Cristiano, Silva, Ivo, Meneses, Filipe, Costa, Antonio, Trogh, Jens, Plets, David, Chien, Ying-Ren, Chang, Tzu-Yu, Fang, Shih-Hau, Tsao, Yu

مصطلحات موضوعية: 4. Education

الوصف: PIN 2019 Competition, sixth in a series of IPIN competitions, was held at the CNR Research Area of Pisa (IT), integrated into the program of the IPIN 2019 Conference. It included two on-site real-time Tracks and three off-site Tracks. The four Tracks presented in this paper were set in the same environment, made of two buildings close together for a total usable area of 1000 m 2 outdoors and and 6000 m 2 indoors over three floors, with a total path length exceeding 500 m. IPIN competitions, based on the EvAAL framework, have aimed at comparing the accuracy performance of personal positioning systems in fair and realistic conditions: past editions of the competition were carried in big conference settings, university campuses and a shopping mall. Positioning accuracy is computed while the person carrying the system under test walks at normal walking speed, uses lifts and goes up and down stairs or briefly stops at given points. Results presented here are a showcase of state-of-the-art systems tested side by side in real-world settings as part of the on-site real-time competition Tracks. Results for off-site Tracks allow a detailed and reproducible comparison of the most recent positioning and tracking algorithms in the same environment as the on-site Tracks.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::426efda1e20144e2838544fd6f6c0f30Test

المؤلفون: Li, Wen^1,2 wen.li@aoe.ac.cn, Wei, Dongyan¹ weidongyan@aoe.ac.cn, Lai, Qifeng^1,2, Li, Xianghong^1,2, Yuan, Hong¹

المصدر: Sensors (14248220). May2018, Vol. 18 Issue 5, p1462. 1p.

مصطلحات موضوعية: *GEOMAGNETISM, *IEEE 802.11 (Standard), *SMARTPHONES, *CROWDSOURCING, *PROBLEM solving

مستخلص: Wi-Fi radio-map construction is an important phase in indoor fingerprint localization systems. Traditional methods for Wi-Fi radio-map construction have the problems of being time-consuming and labor-intensive. In this paper, an indoor Wi-Fi radio-map construction method is proposed which utilizes crowdsourcing data contributed by smartphone users. We draw indoor pathway map and construct Wi-Fi radio-map without requiring manual site survey, exact floor layout and extra infrastructure support. The key novelty is that it recognizes road segments from crowdsourcing traces by a cluster based on magnetism sequence similarity and constructs an indoor pathway map with Wi-Fi signal strengths annotated on. Through experiments in real world indoor areas, the method is proved to have good performance on magnetism similarity calculation, road segment clustering and pathway map construction. The Wi-Fi radio maps constructed by crowdsourcing data are validated to provide competitive indoor localization accuracy. [ABSTRACT FROM AUTHOR]