Utilization of Quasi-Zenith Satellite System for Navigation of a Robot Combine Harvester

The purpose of this study is to evaluate the performance of a robot combine harvester by comparing the Centimeter Level Augmentation Service (CLAS) and the Multi-Global Navigation Satellite System (GNSS) Advanced Demonstration tool for Orbit and Clock Analysis (MADOCA) from the Quasi-Zenith Satellite System (QZSS) by using the Real Time Kinematic (RTK) positioning technique as a reference. The first section of this study evaluates the availability and the precision under static conditions by measuring the activation time, the reconnection time, and obtaining a Twice Distance Root Mean Square (2DRMS) of 0.04 m and 0.10 m, a Circular Error Probability (CEP) of 0.03 m and 0.08 m, and a Root Mean Square Error (RMSE) of 0.57 m and 0.54 m for the CLAS and MADOCA, respectively. The second section evaluates the accuracy under dynamic conditions by using a GNSS navigation-based combine harvester running in an experimental field. The results show that the RMSE of the lateral deviation is between 0.04 m and 0.69 m for MADOCA and between 0.03 m and 0.31 m for CLAS; which suggest that the CLAS positioning augmentation system can be utilized for the robot combine harvester if the user considers these accuracy and dynamic characteristics.

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Geostatistical Modelling and Mapping of the Concentration of Gaseous Pollutants

Nigerian Journal of Environmental Sciences and Technology - March 2018 ◽

10.36263/nijest.2018.02.0084 ◽

2018 ◽

Vol 2 (2) ◽

pp. 219-232

Author(s):

J. S. Okpoko ◽

H. A. P. Audu

Keyword(s):

Root Mean Square ◽

Gas Flow ◽

Fine Particulate Matter ◽

Satellite System ◽

Gaseous Pollutants ◽

Mean Square ◽

Kriging Method ◽

Geospatial Modelling ◽

Gis Environment ◽

Global Navigation Satellite

In this study, the prediction of the concentration of gaseous pollutants around Ughelli West gas flow station in Delta State of Nigeria was carried out using Geostatistical technique in GIS environment. Since air pollutants negatively affect quality of air, lives and the environment, there is therefore the need to frequently monitor air quality, have thorough understanding of the pollutants’ concentration and their spatial distribution in an environment. The gaseous pollutants data of volatile organic compounds (VOCs), methane (CH4), nitrogen dioxide (NO2), sulphur dioxide (SO2) and ozone (O3), were obtained using Multi-parameter gas monitor while that of fine particulate matter (PM2.5) was obtained with SPM meter for a period of three months. Thermo Anemometer was used to obtain the values of wind speed, ambient temperature, atmospheric pressure and relative humidity. Artificial Neural Network designer software (Pythia) was used to validate the acquired field data; predict the concentration of the gaseous pollutants at selected distances from the flow station. The geospatial coordinates of the flow station were obtained using Global Navigation Satellite System (GNSS) receivers; the geospatial modelling and analysis were performed with ArcGIS software and ordinary kriging method of Geostatistical techniques. The results of the maximum concentration for the gaseous pollutants in the study area were 28.17 µg/m3, 19.44 µg/m3, 0.37 µg/m3, 49.81 µg/m3, 0.061 µg/m3 and 0.047µg/m3 for VOCs, CH4, NO2, PM2.5, O3 and SO2 respectively. The root mean square error for the concentration of the gaseous pollutants, ozone and sulphur (IV) oxide in the study area were 0.01618 and 0.008417 indicating a good interpolation model, while their root mean square standard errors, which show the reliability of the predicted values, were 0.70513551 and 0.8459251 respectively. These results conform with the report of other researchers that a better kriging method yields a smaller root mean square and a standard root mean square closer to one. The developed prediction maps for the gaseous pollutants in this study revealed that the study area will experience lower concentration of gaseous pollutants at a distance of 400 m and above.

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Global Mean Sea Surface Height Estimated from Spaceborne Cyclone-GNSS Reflectometry

Remote Sensing ◽

10.3390/rs12030356 ◽

2020 ◽

Vol 12 (3) ◽

pp. 356 ◽

Cited By ~ 2

Author(s):

Hui Qiu ◽

Shuanggen Jin

Keyword(s):

Root Mean Square Error ◽

Mean Square Error ◽

Correlation Coefficient ◽

Root Mean Square ◽

Absolute Error ◽

Satellite System ◽

Sea Surface Height ◽

Sea Surface ◽

Mean Square ◽

Mean Sea Surface

Mean sea surface height (MSSH) is an important parameter, which plays an important role in the analysis of the geoid gap and the prediction of ocean dynamics. Traditional measurement methods, such as the buoy and ship survey, have a small cover area, sparse data, and high cost. Recently, the Global Navigation Satellite System-Reflectometry (GNSS-R) and the spaceborne Cyclone Global Navigation Satellite System (CYGNSS) mission, which were launched on 15 December 2016, have provided a new opportunity to estimate MSSH with all-weather, global coverage, high spatial-temporal resolution, rich signal sources, and strong concealability. In this paper, the global MSSH was estimated by using the relationship between the waveform characteristics of the delay waveform (DM) obtained by the delay Doppler map (DDM) of CYGNSS data, which was validated by satellite altimetry. Compared with the altimetry CNES_CLS2015 product provided by AVISO, the mean absolute error was 1.33 m, the root mean square error was 2.26 m, and the correlation coefficient was 0.97. Compared with the sea surface height model DTU10, the mean absolute error was 1.20 m, the root mean square error was 2.15 m, and the correlation coefficient was 0.97. Furthermore, the sea surface height obtained from CYGNSS was consistent with Jason-2′s results by the average absolute error of 2.63 m, a root mean square error ( RMSE ) of 3.56 m and, a correlation coefficient ( R ) of 0.95.

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KONTRIBUSI GLOBAL NAVIGATION SATELLITE SYSTEM PADA PENENTUAN TITIK KONTROL UDARA DI METODE FOTOGRAMETRI UNMANNED AERIAL VEHICLE UNTUK PEMETAAN SKALA BESAR DI INDONESIA

Seminar Nasional Geomatika ◽

10.24895/sng.2020.0-0.1202 ◽

2021 ◽

pp. 867

Author(s):

Irwan Gumilar ◽

Deni Suwardhi ◽

Irfan Budaya ◽

Brian Bramanto ◽

Kamal Nur Fauzan

Keyword(s):

Unmanned Aerial Vehicle ◽

Global Navigation Satellite System ◽

Satellite System ◽

Navigation Satellite ◽

Mean Square ◽

Post Processing ◽

Check Points ◽

Aerial Vehicle ◽

Global Navigation ◽

Global Navigation Satellite

Indonesia saat ini sedang melakukan pemetaan skala besar secara masif. Salah satu metode yang digunakan pada pemetaan skala besar tersebut adalah dengan menggunakan teknik fotogrametri berbasiskan Unmanned Aerial Vehicle (UAV). Saat ini, metode penentuan titik kontrol udara dengan menggunakan Global Navigation Satellite System (GNSS) banyak dilakukan untuk memimalisir jumlah titik kontrol tanah tanpa mengurangi kualitas dari produk fotogrameteri yang dihasilkan. Penelitian ini bertujuan untuk menganalisa kontribusi sistem GNSS pada penentuan titik kontrol udara untuk metode fotogrametri berbasiskan UAV. Pengukuran GNSS frekuensi ganda pada sistem UAV di wilayah Jatinangor, Bandung dan Panglipuran Bali digunakan pada penelitian ini. Panjang baseline antara titik kontrol dan rover berkisar antara 350 hingga 900 m. Penentuan posisi titik kontrol udara berbasiskan GNSS menggunakan metode Post Processing Kinematic (PPK) dengan teknik pemecahan ambiguitas fase LAMBDA Fix and Hold. Pengolahan data GNSS dilakukan dengan menggunakan beberapa kombinasi frekuensi dan sistem GNSS. Evaluasi ketelitian hasil perataan berkas menggunakan titik kontrol udara pada setiap kombinasi frekuensi dan sistem GNSS dilakukan dengan memperhatikan nilai Root Mean Square Error (RMSE) pada 20 titik cek tanah atau Independent Check Points (ICP). Berdasarkan hasil tersebut, kombinasi gelombang L1 dan L2 menggunakan sistem GPS dan BeiDou idealnya digunakan untuk pemetaan skala besar menggunakan fotogrametri UAV. Selain itu, kombinasi data GPS dan Beidou frekuensi ganda memiliki tingkat ketelitian titik kontrol udara yang terbaik dibandingkan kombinasi yang lainnya. Selain itu, kombinasi GPS dan BeiDou menggunakan hanya gelombang L1 memiliki tingkat ketelitian yang sama dibandingkan dengan GPS menggunakan gelombang L1 dan L2.

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Research of the Influence of Road Excitation on Human Body Comfort under the Harvester Working Condition

Applied Engineering in Agriculture ◽

10.13031/aea.13315 ◽

2019 ◽

Vol 35 (4) ◽

pp. 495-502

Author(s):

Wei Jiang ◽

Jie Zhou ◽

Hongmei Xu ◽

Shuang Liu ◽

Chenglong Wang ◽

...

Keyword(s):

Root Mean Square ◽

Human Body ◽

Surface Hardness ◽

Low Frequency ◽

Road Surface ◽

Mean Square ◽

Low Frequency Vibration ◽

Road Excitation ◽

Combine Harvester ◽

Road Surface Roughness

Abstract. When the harvester travels in the field, road excitation will cause low-frequency vibration within 3 Hz, which is the most sensitive frequency range of human body. In order to evaluate the influence of road excitation on the comfort feelings of the harvester driver, vibration acceleration data were collected when the combine harvester was travelling at high and low speeds on flat-soft road, flat-solid road, and rough-solid road. The vibration comfort of the harvester was evaluated by root mean square (RMS) of weighted acceleration. The results showed that the speed of harvester, road surface roughness and hardness have great effects on harvester vibration comfort. Soft road has an obvious absorption effect on the vibration at 70 Hz. The increase in the speed of harvester and road surface hardness and roughness elevates the subjective discomfort of the driver. Keywords: Combine harvester, Comfort research, Road excitation, Root mean square of weighted acceleration, Vibration test.

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Assessment of Dual Frequency GNSS Observations from a Xiaomi Mi 8 Android Smartphone and Positioning Performance Analysis

Electronics ◽

10.3390/electronics8010091 ◽

2019 ◽

Vol 8 (1) ◽

pp. 91 ◽

Cited By ~ 44

Author(s):

Umberto Robustelli ◽

Valerio Baiocchi ◽

Giovanni Pugliano

Keyword(s):

Root Mean Square Error ◽

Mean Square Error ◽

Global Navigation Satellite System ◽

Carrier Phase ◽

Single Point ◽

Satellite System ◽

Navigation Satellite ◽

Mean Square ◽

Dual Frequency ◽

Global Navigation Satellite

On May 2018 the world’s first dual-frequency Global Navigation Satellite System (GNSS) smartphone produced by Xiaomi equipped with a Broadcom BCM47755 chip was launched. It is able to receive L1/E1/ and L5/E5 signals from GPS, Galileo, Beidou, and GLONASS (GLObal NAvigation Satellite System) satellites. The main aim of this work is to achieve the phone’s position by using multi-constellation, dual frequency pseudorange and carrier phase raw data collected from the smartphone. Furthermore, the availability of dual frequency raw data allows to assess the multipath performance of the device. The smartphone’s performance is compared with that of a geodetic receiver. The experiments were conducted in two different scenarios to test the smartphone under different multipath conditions. Smartphone measurements showed a lower C/N0 and higher multipath compared with those of the geodetic receiver. This produced negative effects on single-point positioning as showed by high root mean square error (RMS). The best positioning accuracy for single point was obtained with the E5 measurements with a DRMS (horizontal root mean square error) of 4.57 m. For E1/L1 frequency, the 2DRMS was 5.36 m. However, the Xiaomi Mi 8, thanks to the absence of the duty cycle, provided carrier phase measurements used for a static single frequency relative positioning with an achieved 2DRMS of 1.02 and 1.95 m in low and high multipath sites, respectively.

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Evaluation The Performance Geodetic of the Receivers Using Static Positioning Technique

Journal of Engineering ◽

10.31026/j.eng.2018.10.08 ◽

2018 ◽

Vol 24 (10) ◽

pp. 98

Author(s):

Omar Ali Ibrahim

Keyword(s):

Satellite Communications ◽

Satellite System ◽

Web Based ◽

Static Mode ◽

Total Station ◽

Land Surveying ◽

Gnss Receivers ◽

Positioning Technique ◽

Mobile Satellite ◽

Global Navigation Satellite

Global Navigation Satellite System (GNSS) is considered to be one of the most crucial tools for different applications, i.e. transportation, geographic information systems, mobile satellite communications, and others. Without a doubt, the GNSS has been widely employed for different scientific applications, such as land surveying, mapping, and precise monitoring for huge structures, etc. Thus, an intense competitive has appeared between companies which produce geodetic GNSS hardware devices to meet all the requirements of GNSS communities. This study aims to assess the performance of different GNSS receivers to provide reliable positions. In this study, three different receivers, which are produced by different manufacturers, were fixed to form a triangle. Simultaneous observations were made in static mode (2.5 to 3 hours). This observation technique was carried out three times by changing the location of receivers in each time to ensure that three receivers observed each station three times. To evaluate the performance of each receiver, OPUS web-based processing software and TOPCON TOOLS were used to process the raw GNSS observations. The distances between adjacent stations were computed for each observation and compared to standard distances, which were measured using a total station. Furthermore, the internal angles were also computed and compared to those measured by Total Stations. The results showed that some calculated distances are closer to the corresponding distances measured by the total station. This indicates that the receivers involved in the composition of these distances are the most accurate.

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Positioning Using IRIDIUM Satellite Signals of Opportunity in Weak Signal Environment

Electronics ◽

10.3390/electronics9010037 ◽

2019 ◽

Vol 9 (1) ◽

pp. 37 ◽

Cited By ~ 1

Author(s):

Zizhong Tan ◽

Honglei Qin ◽

Li Cong ◽

Chao Zhao

Keyword(s):

Estimation Algorithm ◽

Satellite System ◽

Positioning System ◽

Weak Signal ◽

Open Environment ◽

Signal Characteristics ◽

Signal Environment ◽

Positioning Technique ◽

Global Navigation Satellite ◽

Signals Of Opportunity

In order to get rid of the dependence of the navigation and positioning system on the global navigation satellite system (GNSS), radio, television, satellite, and other signals of opportunity (SOPs) can be used to achieve receiver positioning. The space-based SOPs based on satellites offer better coverage and availability than ground-based SOPs. Based on the related research of Iridium SOPs positioning in the open environment, this paper mainly focuses on the occluded environment and studies the Iridium SOPs positioning technique in weak signal environment. A new quadratic square accumulating instantaneous Doppler estimation algorithm (QSA-IDE) is proposed after analysing the orbit and signal characteristics of the Iridium satellite. The new method can improve the ability of the Iridium weak signal Doppler estimation. The theoretical analysis and positioning results based on real signal data show that the positioning based on Iridium SOPs can be realized in a weak signal environment. The research broadens the applicable environment of the Iridium SOPs positioning, thereby improving the availability and continuity of its positioning.

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INTEGRATION OF PDR AND IMAGE-BASED POSITIONING AIDED BY ARTIFICIAL NEURAL NETWORKS IN INDOOR ENVIRONMENT

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xliii-b1-2020-181-2020 ◽

2020 ◽

Vol XLIII-B1-2020 ◽

pp. 181-185

Author(s):

M. C. Hung ◽

K. W. Chiang

Keyword(s):

Dead Reckoning ◽

Satellite System ◽

Indoor Positioning ◽

Indoor Navigation ◽

Positioning Method ◽

Pros And Cons ◽

Positioning Technique ◽

The Mean ◽

Global Navigation Satellite ◽

The Cost

Abstract. Location based service (LBS) is a popular issue in recent years, which can be applied widely. The most common one is providing the local information and the guide of the Point of Interesting (POI) to users, which means positioning is the necessary technique to put LBS into practice. In an outdoor scenario, the user’s position can be obtained relying on the Global Navigation Satellite System (GNSS), however, the signal of GNSS might be blocked in a building. So, many indoor positioning techniques are developed in the decades, which have the pros and cons respectively. This paper proposes an indoor positioning technique by integrating Pedestrian Dead Reckoning (PDR) with the image-based positioning method, which can decrease the cost significantly because it only needs a camera built-in the smartphone. In the first experiment, we verify the accuracy of positioning by the proposed method, that the mean error in the horizontal direction is about 0.25 meters. In the following experiment, comparing with the misclosure of PDR only and PDR integrated with the proposed method, it can decrease from 8.53% to 1.44%. The improvement is about 83%, therefore, this method is suitable for applying to indoor navigation.

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Feasibility Analysis of Magnetic Navigation for Vehicles

Sensors ◽

10.3390/s19245410 ◽

2019 ◽

Vol 19 (24) ◽

pp. 5410

Author(s):

Dongyan Wei ◽

Lichen Huang ◽

Xinchun Ji ◽

Wen Li ◽

Yi Lu ◽

...

Keyword(s):

Satellite System ◽

Statistical Characteristics ◽

Distribution Model ◽

Magnetic Navigation ◽

Proposed Model ◽

Positioning Technique ◽

Global Navigation Satellite ◽

The Magnetic Field ◽

Comprehensive Indicator ◽

Matching Window

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.

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A UAV–RTK Lidar System for Wave and Tide Measurements in Coastal Zones

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-17-0199.1 ◽

2018 ◽

Vol 35 (8) ◽

pp. 1557-1570 ◽

Cited By ~ 3

Author(s):

Zhi-Cheng Huang ◽

Cheng-Yang Yeh ◽

Kuo-Hsin Tseng ◽

Wen-Yang Hsu

Keyword(s):

Root Mean Square ◽

Low Cost ◽

Surface Displacement ◽

Ground Truth ◽

Satellite System ◽

Mean Square ◽

Coastal Zones ◽

Lidar System ◽

Tidal Elevation ◽

Mean Square Errors

AbstractA lightweight and low-cost unmanned aerial vehicle (UAV) system for coastal wave and tide measurements is developed. This system is based on an assembly of a multirotor UAV, a robotic lidar, an altitude and heading reference system (AHRS), and a real-time kinematic (RTK) Global Navigation Satellite System (GNSS). A great advantage of the system is that it can be operated at low altitude in a few meters; the accuracy and spatial resolution can therefore be increased. When the system was moved up and down in 2–12 m, the root-mean-square error (RMSE) was approximately 5 cm compared to the ground truth value measured by a manual RTK GNSS. The system was operated in a hover mode to measure the tide and waves in the field. The results of using the UAV–RTK lidar system were consistent with those of in situ measurements using a pressure sensor. The root-mean-square errors between the two techniques for measurements of tidal elevation, significant wave height, and wave period were 4.9 cm, 4.8 cm, and 0.028 s, respectively. This finding suggests the system could be applied to measure instantaneous sea surface displacement. The system provides the potential for using a low-cost, extremely portable, and efficient tool for monitoring wave properties, topographic changes, and water-level gradients in coastal zones.

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