scholarly journals Close Range Photogrammetry and Thermal Imagery in Monitoring of Soil Moisture in Dam Structures of Historical Fishponds

Proceedings ◽  
2018 ◽  
Vol 2 (11) ◽  
pp. 623 ◽  
Author(s):  
Josef Krása ◽  
Václav David

Degradation of reservoir dams can lead to water percolation through dam structure. Here, close-range photogrammetry and UAV (Unmanned Aerial Vehicle) thermal imagery can be used to monitor differences in dam moisture. The article presents a study of the dam of Podvinak Fishpond (Czech Republic). The TDR (Time Domain Reflectometry) data (soil moisture), the Theta probe data (soil moisture), and the temperature data of the dam top profile and the grassed area below the dam were compared. Analysis focused on the comparison between sampled data, and UAV data obtained by Optris TIM 450 (Portsmouth, USA) and Flir Tau2 336 (Wilsonville, USA) IR cameras. Based on the study, the spectral resolution, the accuracy of the results, and the reliability of both UAV monitoring systems is similar.

2012 ◽  
Vol 626 ◽  
pp. 440-444 ◽  
Author(s):  
Munirah Radin Mohd Mokhtar ◽  
Abdul Nasir Matori ◽  
Hj Khamaruzaman Hj Wan Yusof ◽  
Imtiaz Ahmed Chandio ◽  
Duong Tuan Viet ◽  
...  

This paper presents the preliminary work is a part of a research focusing on close range photogrammetry for landslide monitoring.The main objective of this paper is to present the Close Range Photogrammetry (CRP) technique, Unmanned Aerial Vehicle (UAV) will provide a platform to monitor the surface area This method was applied using the capabilities and power of Gatewing, Unmanned Aerial Vehicle (UAV) for data capturing with respect to UAV tracking conducted in UTP, Tronoh, Perak, on 15th March 2012 at 150m height. The Gatewing is designed for rapid terrain mapping with fully automated image processing. The result proves that data processing were conducted by Srecthout Software. Flight planning was carried out on site, where the areas to be observed are situated inside the UTP campus. The paper focus on final production of an orthomosaic. In conclusion, it is demonstrated that Gatewing, UAV is the best, fast and powerful mapping vehicle for close range photogrammetry application in future works. It shows highly excellent performance compared to other UAVs already established in the market today. Keywords: Unmanned Aerial Vehicle (UAV); Close Range Photogrammetry (CRP); Gatewing; orthomosaic; terrain.


2011 ◽  
Vol 130-134 ◽  
pp. 2404-2408
Author(s):  
Jun Ma ◽  
Wen Ying Su

In view of the heavy workload and possible intervention to the normal traffic flow during the performance testing of road traffic signs, this paper is designed to present a system that can be installed in an automobile and automatically track and analyze the performance of traffic signs. The system consists of a carrying vehicle, GPS, IMU, area-array cameras, frame grabbers, data acquisition software and data analysis software. Based on close-range photogrammetry technology, the system is designed with a set of effective road traffic signs automatic detection algorithms, which can automatically measure and analyze the properties of road traffic signs, such as dimensions, headroom and verticality of the column, etc.


2021 ◽  
Vol 11 (6) ◽  
pp. 2785
Author(s):  
Michael Lösler ◽  
Cornelia Eschelbach ◽  
Thomas Klügel ◽  
Stefan Riepl

A global geodetic reference system (GGRS) is realized by physical points on the Earth’s surface and is referred to as a global geodetic reference frame (GGRF). The GGRF is derived by combining several space geodetic techniques, and the reference points of these techniques are the physical points of such a realization. Due to the weak physical connection between the space geodetic techniques, so-called local ties are introduced to the combination procedure. A local tie is the spatial vector defined between the reference points of two space geodetic techniques. It is derivable by local measurements at multitechnique stations, which operate more than one space geodetic technique. Local ties are a crucial component within the intertechnique combination; therefore, erroneous or outdated vectors affect the global results. In order to reach the ambitious accuracy goal of 1 mm for a global position, the global geodetic observing system (GGOS) aims for strategies to improve local ties, and, thus, the reference point determination procedures. In this contribution, close range photogrammetry is applied for the first time to determine the reference point of a laser telescope used for satellite laser ranging (SLR) at Geodetic Observatory Wettzell (GOW). A measurement campaign using various configurations was performed at the Satellite Observing System Wettzell (SOS-W) to evaluate the achievable accuracy and the measurement effort. The bias of the estimates were studied using an unscented transformation. Biases occur if nonlinear functions are replaced and are solved by linear substitute problems. Moreover, the influence of the chosen stochastic model onto the estimates is studied by means of various dispersion matrices of the observations. It is shown that the resulting standard deviations are two to three times overestimated if stochastic dependencies are neglected.


2021 ◽  
Author(s):  
Ali Mirzazade ◽  
Cosmin Popescu ◽  
Thomas Blanksvärd ◽  
Björn Täljsten

<p>In bridge inspection, vertical displacement is a relevant parameter for both short and long-term health monitoring. Assessing change in deflections could also simplify the assessment work for inspectors. Recent developments in digital camera technology and photogrammetry software enables point cloud with colour information (RGB values) to be generated. Thus, close range photogrammetry offers the potential of monitoring big and small-scale damages by point clouds. The current paper aims to monitor geometrical deviations in Pahtajokk Bridge, Northern Sweden, using an optical data acquisition technique. The bridge in this study is scanned two times by almost one year a part. After point cloud generation the datasets were compared to detect geometrical deviations. First scanning was carried out by both close range photogrammetry (CRP) and terrestrial laser scanning (TLS), while second scanning was performed by CRP only. Analyzing the results has shown the potential of CRP in bridge inspection.</p>


2018 ◽  
Vol 7 (9) ◽  
pp. 350 ◽  
Author(s):  
Luis López-Fernández ◽  
Susana Lagüela ◽  
Pablo Rodríguez-Gonzálvez ◽  
José Martín-Jiménez ◽  
Diego González-Aguilera

Close-range photogrammetry and thermographic imaging techniques are used for the acquisition of all the data needed for the non-invasive assessment of a honeybee hive population. Temperature values complemented with precise 3D geometry generated using novel close-range photogrammetric and computer vision algorithms are used for the computation of the inner beehive temperature at each point of its surface. The methodology was validated through its application to three reference beehives with different population levels. The temperatures reached by the exterior surfaces of the hives showed a direct correlation with the population level. In addition, the knowledge of the 3D reality of the hives and the position of each temperature value allowed the positioning of the bee colonies without the need to open the hives. This way, the state of honeybee hives regarding the growth of population can be estimated without disturbing its natural development.


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