RETIME software for real time data acquisition using LEICA TCA series

Industrial survey is a discipline of engineering surveys that requires the utmost in achievable accuracies and real time data processing. The instrumentation used in conventional industrial survey requires long painstaking procedures with very skilled craftsmen to obtain the required results. Revolution of technology with the introduction of new instruments (such as total station, computer and software) has revolutionized industrial survey. The development of three dimensional (3D) coordinating system and total station interfaced to a microcomputer provides the capabilities for on line data gathering with simultaneous processing in 3D. This research concentrates on the development of software to acquire data from robotic total station (RTS) TCA2003 in real time. This software called RETIME is a short form of REal TIME. RETIME software consisted of the three core module i.e. (i) Data communication with RTS TCA2003, (ii) Calculate the raw data to produce 3D coordinates, and (iii) Convert the data from RETIME format into STAR*NET format. STAR*NET software (third party software) has been used in this research to provide an adjusted data. For verification purpose, RETIME software has been evaluated and the resulted are acceptable for industrial survey environment

Digital aerial imagery of unmanned aerial vehicle for various applications

Digital aerial imagery (DAI) can be acquired using digital mapping camera attached to light aircraft. The DAI is used for the production of topographic and thematic map. The cost of acquiring DAI is very expensive and suitable for large area coverage. The acquisition of DAI is not economical and suitable for small area coverage. Therefore an alternative method should be used to fulfill this need. There are two alternative methods that can be used for acquisition of DAI which include using a small format digital camera attached to light aircraft and using a small format attached to an unmanned aerial vehicle (UAV). UAV system has been reported used in various and diversified applications such as mapping applications (eg. map revision, landslide, coastal erosion, archaeology, forestry), industrial application (eg. engineering, crash accident), Geographic Information System (GIS) applications and others. In this study, micro unmanned aerial vehicle (UAV) systems which comprise of fixed wing UAV flying and rotary UAV are attached with small format high resolution digital camera to acquire DAI for the purpose of mapping at the flying height of 300m at 100m respectively. The micro UAVs were flown autonomously (i.e automatically) and a series of DAIs of a slope using fixed wing UAV and a stream using rotary UAV were acquired rapidly within short period. Ground control point (GCP) and check point (CP) were established using the Global Positioning System and conventional Total Station techniques around the study area for the slope and stream respectively for the purpose of digital image processing and accuracy assessment. The DAIs were processed to produce photogrammetric output such as digital elevation model (DEM) and orthophoto. All these photogrammetric products were successfully produced and assessed. The achievable accuracy is less than ±1m for slope mapping and ±0.280m for stream mapping. In this study, it is proven that the micro UAV system can be used for mapping which cover small area. As conclusion, micro UAV is suitable for mapping small area, rapid data acquisition, accurate, low cost and can be employed for various applications

Penilaian kesesuaian kaedah fotogrametri digital jarak dekat untuk pengukuran objek tiga dimensi

This study concentrates on the use of digital close range photogrammetric method. This method can be used in various field such as industrial, engineering, medical, archaeology and architecture. The aim of this study is to investigate the use of digital photogrammetric method for measurement of 3D object and generating 3D model. In this study, four different test objects were used which comprised of the replica of bottle, cylinder pipe, Multi Mission Vessel (MMV) hull model and four wheel drive vehicle. For each test object, retro-reflective targets are sticked to it. Then, digital images surrounding the test object were acquired using digital camera and convergent configuration. After the imaging process, these images were processed using two digital close range photogrammetric softwares known as Australis and PhotoModeler. The output from the two softwares is 3D coordinates. Next the 3D coordinates were input into modeling software to generate 3D model of the test object. For accuracy assessment of measurement, geodetic method and VSTARS system are used. Results of the study showed that the mean accuracy for Australis is between ±0.023 mm to ±0.499, while the mean accuracy for PhotoModeler is between ±0.106 mm to ±1.361 mm. In conclusion, this study shows that digital close range photogrammetric method can be used for measurement of 3D object and generating 3D model

Penilaian kuantitatif produk fotogrametri berasaskan pesawat udara tanpa pemandu untuk pemetaan topografi skala besar

The use of aircraft in the field of topographic mapping is not exactly a new but rather it has been main method in topographic map production since the early 20th century. Commonly known by the name, photogrammetry - this method relies on the camera for an aerial image acquisition that is sited on the piloted aircraft platform. Nowadays, much attention has been given to the use of Unmanned Aerial Vehicles (UAV), which has become a popular platform especially for the purpose of large-scale topographic mapping. Therefore, this research focuses on the potential of Fixed Wing UAV as an aerial image acquisition platform to produce photogrammetric products such as Digital Terrain Model (DTM) and Orthophoto for large-scale topographic mapping. Correspondingly, all relevant aspects are taken into account starting from the flight planning, aerial photography, camera calibration, camera settings, Ground Control Points (GCP) distribution, and data processing up to the accuracy standard of the mapping product generation. The research area for this study are Cameron Highlands, Pahang and UiTM Arau, Perlis Campus. Photo control and verification points are determined by GPS (Global Positioning System) surveying method. The image processing for the purpose of DTM and Orthophoto generation are establish using Agisoft™ software, assisted by ArcMap™ and Topcon Tool™ software. Results show that flight plan that consists of camera calibration process, camera configuration settings, flying altitude, percentage of image overlap and location of control point are the major factors for mapping product accuracy using this method. Assessment of mapping products found that mapping accuracy is within the standard tolerance as set by the American Society of Photogrammetry and Remote Sensing (ASPRS) which in average are in sub-meter with square root mean error (RMSE) for the planimetric coordinates (northing, easting) and hypsometric (elevation) are ± 0.300 meter, and ± 0.400 meter respectively. This also proves that digital images taken using compact digital camera from fixed wing UAV platform is capable of generating good and accurate mapping products

Assessment of low altitude aerial data for large scale urban environmental mapping

Development of UAV systems become more popular for missions with high societal impact. Therefore, UAV is developed from the low-altitude photogrammetric mapping to perform the accuracy of the aerial photography and the resolution of the image. The objective of this study is to assess the accuracy of the photogrammetric output i.e. Digital Elevation Model (DEM) and orthophoto. The Ground Control Points (GCPs) and Check Points (CPs) are established using Rapid Static techniques through GPS observation for registration purpose in photogrammetric process. The GCPs is used in the photogrammetric processes to produce photogrammetric output while the CP is employed for accuracy assessment. A Pentax Optio W90 consumer digital camera is also used in image acquisition of the aerial photograph. Besides, this study also involves image processing and map production using Erdas Imagine 8.6 software. The accuracy of the orthophoto is determined using the equation of Root Mean Square Error (RMSE). In a nutshell, UAV system has potential use for largescale urban environmental mapping in field of surveying and other diversified urban environmental applications especially for small area which has limited time and less man power

Accuracy assessment of calibrating high resolution digital camera

Today many photogrammetric works involved the use of digital cameras due to it's in low cost. Digital camera has been used in many photogrammetric applications such as archaeology, architecture, accident investigation, cultural heritage and etc. Theoretically, most digital camera is known as non-metric camera where the interior geometrical of digital camera is not stable, however, the optical quality is not acceptable. The need for camera calibration has been fundamental requirement for obtaining accurate measurement since the inception of photogrammetry. This study deals with the acquisition and processing of different configuration of digital camera (convergent and generic network) which are position at different height versus different digital camera setup. The accuracy assessment was performed for two high resolution digital cameras which are Nikon D90 and Rollei D30metric5 digital cameras. The height of digital camera is setup at approximately 80cm and 100cm. Finally, this study evaluates the accuracy of the camera calibration based on standard deviation of interior camera calibration parameters. This study shows that high resolution Nikon D90 digital camera which is categorized as low cost could be used in photogrammetric application with good accuracy achievable

Comparative geometric and radiometric evaluation of mobile phone, compact and DSLR cameras

Progress development in digital imaging system has impacted in many fields including close range photogrammetry (CRP). With the improvement in resolution of digital imaging, the image qualities of digital imaging especially non-metric cameras is increasingly optimized. The recent increase in number of pixels of non-metric digital camera and hand phone camera has encouraged the needs to utilize it for CRP applications such as 3D measurement and creations of orthoimages. The objective of this study is to evaluate the performance of non-metric cameras used in CRP. In this study, three non-metric cameras which are Digital Single-Lens Reflex (DSLR), compact and mobile phone are calibrated and tested based on geometric and radiometric characteristics. Geometric performance test is carried out by using self-calibration technique where a calibration test field in the form of three-dimensional (3D) was used. The 3D distance measurement is made to verify the accuracy for these cameras. The interior parameters of the cameras were evaluated and analyzed using descriptive analysis and subsequently followed by performing distance measurement. The radiometric capabilities of all cameras were evaluated by carrying out modulation transfer function (MTF) analysis and image noise analysis. The results clearly demonstrate that the potential and the capability of non-metric cameras to measure up to sub-millimeter precision. From this study, it can be concluded that the performance of geometric is generally increases with the radiometric performance