Terrestrial laser scanning for 3D zone substation modelling and safety clearances

Essential Energy is a State Owned Corporation (SOC) responsible for construction and maintenance of the electricity network in NSW. An important part of this network are Zone Substations which are primarily used to transform voltage levels and distribute the voltage at a useable level. Construction and augmentation of Zone Substations requires accurate design drawings to enable upgrade and new installations of plant and equipment. Many of these Substations are ageing assets and do not have accurate design drawings of current equipment layouts. For these sites the inaccuracies contained in old hand drawn general arrangement drawings does not provide a good basis from which to begin a design. The purpose of this Dissertation aims to determine whether Terrestrial Laser Scanning technology could be used to scan existing Zone Substation sites for the purpose of 3D modelling and determining if the sites are compliant with current safety clearance standards. Nevertire Zone Substation is located 100km’s west of the city of Dubbo and this site has been used for the purpose of this document to prove that Terrestrial Laser Scanning equipment can produce accurate 3D models which are able to be used for Zone Substation Design and safety clearance checks. Nevertire Zone Substation was scanned on site with a high definition laser scanner and a 3D model produced in the form of a point cloud file. This point cloud file was then used to produce a 3D wireframe model which can be used for design purposes. The point cloud file and wireframe model were checked for accuracy against on site measurements and both models produced extremely accurate results. These results were then compared directly with conventional survey measurements (already completed at Nevertire Zone Substation) to highlight the differing levels of accuracy available in the different data capture techniques. Using the point cloud file of Nevertire Zone Substation the site was thoroughly analysed to ensure it was compliant with the current Essential Energy and Australian Standards for electrical safety clearances. The Zone Substation lightning protection coverage was also modelled using the point cloud file and rolling sphere method. Results and conclusions produced from the analysis clearly show that there are several existing areas within the Nevertire Zone Substation which do not comply with the required clearances specified by Essential Energy. In addition to the results and conclusions a benefit analysis is provided to highlight the additional value that using this method of data capture has, over using conventional survey techniques. The intention is that Essential Energy will be provided directly with all of the information and results developed throughout the writing of this document. Allowing further work to proceed will be based on decisions made by Essential Energy management on the value that this method will provide to the organisation

Extrinsic Parameter Calibration for Line Scanning Cameras on Ground Vehicles with Navigation Systems Using a Calibration Pattern

Line scanning cameras, which capture only a single line of pixels, have been increasingly used in ground based mobile or robotic platforms. In applications where it is advantageous to directly georeference the camera data to world coordinates, an accurate estimate of the camera's 6D pose is required. This paper focuses on the common case where a mobile platform is equipped with a rigidly mounted line scanning camera, whose pose is unknown, and a navigation system providing vehicle body pose estimates. We propose a novel method that estimates the camera's pose relative to the navigation system. The approach involves imaging and manually labelling a calibration pattern with distinctly identifiable points, triangulating these points from camera and navigation system data and reprojecting them in order to compute a likelihood, which is maximised to estimate the 6D camera pose. Additionally, a Markov Chain Monte Carlo (MCMC) algorithm is used to estimate the uncertainty of the offset. Tested on two different platforms, the method was able to estimate the pose to within 0.06 m / 1.05$^{\circ}$ and 0.18 m / 2.39$^{\circ}$. We also propose several approaches to displaying and interpreting the 6D results in a human readable way.Comment: Published in MDPI Sensors, 30 October 201

Multispectral photography for earth resources

A guide for producing accurate multispectral results for earth resource applications is presented along with theoretical and analytical concepts of color and multispectral photography. Topics discussed include: capabilities and limitations of color and color infrared films; image color measurements; methods of relating ground phenomena to film density and color measurement; sensitometry; considerations in the selection of multispectral cameras and components; and mission planning

Method to Automatically Register Scattered Point Clouds Based on Principal Pose Estimation

Three dimensional (3-D) modeling is important in applications ranging from manufacturing to entertainment. Multiview registration is one of the crucial steps in 3-D model construction. The automatic establishment of correspondences between overlapping views, without any known initial information, is the main challenge in point clouds registration. An automatic registration algorithm is proposed to solve the registration problem of rigid, unordered, scattered point clouds. This approach is especially suitable for registering datasets that are lacking in features or texture. In general, the existing techniques exhibit significant limitations in the registration of these types of point cloud data. The presented method automatically determines the best coarse registration results by exploiting the statistical technique principal component analysis and outputs translation matrices as the initial estimation for fine registration. Then, the translation matrices obtained from coarse registration algorithms are used to update the original point cloud and the optimal translation matrices are solved using an iterative algorithm. Experimental results show that the proposed algorithm is time efficient and accurate, even if the point clouds are partially overlapped and containing large missing regions

CONTAINER SHIP CELL GUIDE ACCURACY CHECK TECHNOLOGY BASED ON IMPROVED 3D POINT CLOUD INSTANCE SEGMENTATION

Generally, cell guides are installed in the cargo hold of container ships, which improve the loading and unloading efficiency of containers and fix containers when the ship is sailing. However, in actual production, due to the low accuracy of ship loading in sections, and the deviation of welding shrinkage and expansion in relevant sections, errors occur in the loading process of containers, resulting in hidden safety risks or significant economic losses. Given the above situation, it is particularly important to find a high-efficiency cell guide accuracy inspection method for construction monitoring. 3D scanner to obtain three-dimensional data is presented in this paper, based on this paper proposes a new method, this method will be used based on improved instances of 3 d point cloud segmentation model to cell guide the segmentation, and fitting container ship cell guide structure, and then realize the function of container simulation test box, cell guide after the segmentation precision inspection at the same time, for the practicality review, we compared the accuracy data gained from inspection simulation and the measured data. As a result, it was confirmed that both values were within about ±1.5mm. The validity, and reliability of the method are further verified

Development of a high precision telescopic instrument based on simultaneous laser multilateration for machine tool volumetric verification

This paper presents the design of a high precision telescopic system consisting in three lines, with measuring principle based on simultaneous laser multilateration. The system offers the high precision of the interferometer systems and allows the autonomous tracking of a sphere joined to the spindle nose of the machine tool by simultaneous contact of all the lines. The main advantage of the system is that it allows data capture to be carried out in a single cycle thanks to simultaneous operation with at least three telescopic arms using a novel multipoint kinematic coupling. This results in a significant reduction of the time taken for data capture and improves measurement accuracy due to avoiding the effect of temperature variations between cycles and machine tool repeatability. The work explains the working principle of the system, its main components, and the design parameters considered for the development of the system. The system is simple to operate, compact, agile, and suitable for the verification of small-or medium-sized machine tools with linear and/or rotary axes

Synthetic Aperture Radar (SAR) data processing

The available and optimal methods for generating SAR imagery for NASA applications were identified. The SAR image quality and data processing requirements associated with these applications were studied. Mathematical operations and algorithms required to process sensor data into SAR imagery were defined. The architecture of SAR image formation processors was discussed, and technology necessary to implement the SAR data processors used in both general purpose and dedicated imaging systems was addressed