Non-metric Camera Research Articles

Effects of camera calibration on the accuracy of Unmanned Aerial Vehicle sensor products

Utilization of Unmanned Aerial Vehicles (UAV) mounted with non-metric consumer grade digital cameras is on the rise globally due to their affordability and ease of operation. For high-accuracy UAV products, there is a need for accurate camera parameters determined through camera calibration. Camera calibration can be performed before (pre-calibration) or during the bundle block adjustment (self-calibration). This study aims to analyze the effect of camera calibration parameters on the accuracy of UAV products namely Digital Elevation Model (DEM) and orthoimage. Camera calibration parameters are estimated using two approaches namely self-calibration which deploys 3D image information of the scene in a bundle adjustment and a 2D reference object-based approach known as Zhang’s technique which requires image information of a planar pattern. A DJI FC220 camera mounted on a DJI Mavic Pro UAV was used. Self-calibration was deployed in Agisoft Metashape software based on Brown’s method and Zhang’s technique was deployed in MATLAB and OpenCV. Based on internal measures of accuracy, OpenCV yields the least reprojection error of 0.14 followed by MATLAB (0.79) and self-calibration (1.21). Processing without calibration yields the highest reprojection error of 2.18. Based on external measures of accuracy, that is the geometric accuracy of UAV products, self-calibration yields the least RMSE of 8.2 and 1.4 cm, for the horizontal and vertical, respectively, followed by Zhang’s technique with 9.6 and 2.3 cm in MATLAB and 13.5 and 4.3 cm in OpenCV. Processing without calibration yields the highest vertical RMSE of 20.0 and 22.9 cm for the horizontal and vertical, respectively. Comparison of accuracy of UAV mapping products computed with and without calibration emphasizes the need for camera calibration to optimize accuracy of UAV products. This study recommends assessing other photogrammetric mapping software and camera calibration approaches and the effect of flying heights on calibration parameters and mapping accuracy.

REVIEW OF THE USE OF DRONES AND NON-METRIC CAMERAS FOR THE PROVISION OF LARGE-SCALE GEOSPATIAL DATA ACCORDING TO BIG REGULATION NO. 1 OF 2020

Currently, the need for large-scale mapping for the entire territory of Indonesia is urgent. Therefore, accelerating the provision of large-scale Geospatial Data (DG) is essential for better spatial planning and regional development. The use of drone technology with non-metric cameras is starting to be used for the provision of large-scale DG. To regulate the use of drones and non-metric cameras, the Geospatial Information Agency issued the Head of Geospatial Information Agency Regulation No. 1 of 2020. The purpose of this paper will review the use of drones with non-metric cameras that have been regulated in the agency's regulations. The method used in this paper uses qualitative research with a data collection strategy or source using the literature method. The results show that the use of direct georeferencing in BIG Regulation No. 1 of 2020 has fulfilled the horizontal and vertical geometry accuracy requirements stipulated in BIG Head Regulation No. 6 of 2018 on Base Map Accuracy. The GSD value requirement in BIG Regulation No 1/2020 is too high compared to the GSD value requirement specified in the ASPRS Accuracy Standards for Digital Geospatial Data. This agency regulation is a standard / reference that must be met for all mapping industry players. Therefore, the implementation of this agency regulation requires further study to truly support the issue of accelerating large-scale mapping.

Geometrical evaluation of the UTFPR-DV building area using images of an unmanned aerial vehicle (UAV) with non-metric camera

Geometrical evaluation of the UTFPR-DV building area using images of an unmanned aerial vehicle (UAV) with non-metric camera

Оценка деформационных процессов фотограмметрическим способом в Agisoft Metashape

Active development of digital cameras and computer software has made close-range photogrammetry an extremely popular way to solve various engineering tasks, in particular, to control deformations of constructions and mining objects. Automated measurement of tie points enables reviving traditional techniques of deformation measurement through single shot photogrammetric approach (a zero basis, pseudo parallaxes) at a qualitatively new level. The paper deals with the contour mapping equal displacement method adaptation offered by the first author in the 1970s for processing in Agisoft Metashape. It is proposed to create a virtual basis for two single multi-temporal images by adding a matrix of empty pixels to them. This enables processing those as stereo pair, building virtual point clouds and altitude matrices. In order to test the technique, the authors considered the deflection deformation of various objects under lab conditions and shot their photos with a non-metric camera before and after loading. The obtained images were processed in Metashape, and then the above products were created and contours of equal deformations were plotted. It was found out that the accuracy of displacement value estimation with this method exceeds the spatial resolution of the images more than three times. The technology is applicable for objects deformations monitoring shifting mainly in a single plane, in future it is planned to test it in field at studying slope processes

A MULTI-PURPOSE USV PROTOTYPE FOR PHOTOGRAMMETRY APPLICATIONS – CASE STUDY OF A 3D MODEL OF THE GRUNWALDZKI BRIDGE (WROCŁAW, POLAND)

Abstract. The BATDRON Unmanned Surface Vessel is an original structure developed at Wrocław University of Science and Technology, intended to conduct measurements using a diverse range of sensors. Initially, it was used to measure the geometry of reservoirs and waterways, however, owing to the constant development of the platform, it was possible to use a new sensor – a non-metric camera, and to carry out photogrammetric measurements. The first tests were carried out using a NIKON D800 camera and included measuring the Grunwaldzki Bridge in Wrocław.The analysis of the trajectory of the BATDRON remotely controlled (RC) vessel demonstrated that it maintains the programmed course (the average value of the distance from the set mission route was -0.04 m), which is of great importance in the case of photogrammetric measurement sessions. Also, the internal quality control (IQC) of data obtained from the non-metric camera in relation to reference data obtained with a Riegl laser scanner showed satisfactory accuracy of photogrammetric data.

Analysis of the residual distortion and forward motion influence on the accuracy of spatial coordinates determination based on UAV survey

The purpose of this work is to study the operation of a non-metric digital camera Canon EOS 5D Mark III installed on a DJI S1000 octocopter, regarding the accuracy of spatial coordinates determination on images, and perform the identification and analysis of errors affecting the accuracy of stereophotogrammetry survey. During the experimental part, we conducted the stereophotogrammetric and aerial surveys of the areas including marked points. This served as a source of data for creating stereo models with their subsequent processing with the use of the Delta 2 software. The catalogs of spatial coordinates of the marked points were formed according to measurements taken by the Trimble M3 DR Total Station and from stereo models. We calculated the differences and defined root-mean-square error of determining the spatial coordinates of the points on images. Considering the specifics of the marked points placement on the studied sites, we also calculated the errors of image displacements caused by terrain. Additionally, the research studied the influence of camera`s forward motion on the accuracy of survey data of unmanned aerial vehicle (UAV). The obtained results confirm the presence of residual distortion in the optical system of the Canon EOS 5D Mark III digital camera. This leads to the need to calibrate the camera for improving the accuracy of the obtained images for their further use in mapping, monitoring geomorphological processes and phenomena, creating a Digital Elevation Model, etc. Also, the study revealed the influence of forward motion of the survey camera and image displacements caused by the height difference of the survey sites on the accuracy of created stereo models. The authors proposed a configuration and created an experimental site of marked control points on the ground for calibrating a digital non-metric camera in conditions as close as possible to the real survey conditions. Considering the analyzed literary sources, it is more effective than calibration in a laboratory.

NORMAL AND CONVERGENT METHODS OF SURVEY FOR INVENTORY AND CERTIFICATION OF CULTURAL STRUCTURES

The article aims to study the use of normal and convergent stereo-photographic techniques to determine physical condition of a building, to compare errors obtained using a digital non-specialized camera, and use these methods in the inventory and certification of real estate. Monitoring architectural monuments is currently one of the most urgent problems. The development of large cities in which architectural monuments are under threat of destruction requires modern and effective technology for monitoring which is possible using low-cost photogrammetry methods: digital images and cheap software. The development of digital cameras into terrestrial photogrammetry resulted in fundamentally new methods and photogrammetric technologies. In case of monitoring objects of small sizes, such as architectural monuments, the cost of shooting equipment is one of the most significant factors, which reduces the cost of work, therefore, in the vast majority of cases, only digital non-metric cameras are used for shooting. The most significant problem is the calibration of digital non-metric cameras. Currently, a huge number of options for calibrating digital cameras have been developed. These options differ in calibration method, type of test object, type of mathematical model for accounting for distortion (algebraic, physical or hybrid model) The present study how that accuracy of the convergent method is almost 2 times higher than that of the normal photogrammetric survey method and provides a large survey overlap area. Comparing all the indicators and characteristics of these methods, we concluded the feasibility, high profitability, and low complexity of the convergent method of stereo photography to perform inventory and certification of real estate. We found that when surveying building using convergent method it is necessary to use 2 times fewer stations than when surveying by normal method. Thus, the convergent method is 2 times faster and more efficiently.

GNSS-Assisted Low-Cost Vision-Based Observation System for Deformation Monitoring

This paper considers an approach to solve the structure monitoring problem using an integrated GNSS system and non-metric cameras with QR-coded targets. The system is defined as a GNSS-assisted low-cost vision-based observation system, and its primary application is for monitoring various engineering structures, including high-rise buildings. The proposed workflow makes it possible to determine the change in the structure geometric parameters under the impact of external factors or loads and in what follows to predict the displacements at a given observation epoch. The approach is based on the principle of relative measurements, implemented to find the displacements between pairs of images from non-metric cameras organized in a system of interconnected chains. It is proposed to determine the displacement between the images for different epochs using the phase correlation algorithm, which provides a high-speed solution and reliable results. An experimental test bench was prepared, and a series of measurements were performed to simulate the operation of one vision-based observation system chain. A program for processing the sequence of images in the MatLab programming environment using the phase correlation algorithm was implemented. An analysis of the results of the experiment was carried out. The analysis results allowed us to conclude that the suggested approach can be successfully implemented in compliance with the requirements for monitoring accuracy. The simulation of the vision-based observation system operation with accuracy estimation was performed. The simulation results proved the high efficiency of the suggested system.

CRBeDaSet: A Benchmark Dataset for High Accuracy Close Range 3D Object Reconstruction

This paper presents the CRBeDaSet—a new benchmark dataset designed for evaluating close range, image-based 3D modeling and reconstruction techniques, and the first empirical experiences of its use. The test object is a medium-sized building. Diverse textures characterize the surface of elevations. The dataset contains: the geodetic spatial control network (12 stabilized ground points determined using iterative multi-observation parametric adjustment) and the photogrammetric network (32 artificial signalized and 18 defined natural control points), measured using Leica TS30 total station and 36 terrestrial, mainly convergent photos, acquired from elevated camera standpoints with non-metric digital single-lens reflex Nikon D5100 camera (ground sample distance approx. 3 mm), the complex results of the bundle block adjustment with simultaneous camera calibration performed in the Pictran software package, and the colored point clouds (ca. 250 million points) from terrestrial laser scanning acquired using the Leica ScanStation C10 and post-processed in the Leica Cyclone™ SCAN software (ver. 2022.1.1) which were denoized, filtered, and classified using LoD3 standard (ca. 62 million points). The existing datasets and benchmarks were also described and evaluated in the paper. The proposed photogrammetric dataset was experimentally tested in the open-source application GRAPHOS and the commercial suites ContextCapture, Metashape, PhotoScan, Pix4Dmapper, and RealityCapture. As the first experience in its evaluation, the difficulties and errors that occurred in the software used during dataset digital processing were shown and discussed. The proposed CRBeDaSet benchmark dataset allows obtaining high accuracy (“mm” range) of the photogrammetric 3D object reconstruction in close range, based on a multi-image view uncalibrated imagery, dense image matching techniques, and generated dense point clouds.

THE APPLICATION OF SMARTPHONE BASED STRUCTURE FROM MOTION (SFM) PHOTOGRAMMETRY IN GROUND VOLUME MEASUREMENT

Abstract. The purpose of this research study is to assess the potential using smartphone camera captured images for 3D model reconstruction by using Structure from Motion (SFM) photogrammetry technique, specifically in term of volumetric measurement. In past, the volumetric measurement of surface or object is by using Imaging Station or by professional Terrestrial Laser Scanner (TLS), however such approach is expensive in labour fees and instruments fee respectively. A cheaper alternative is necessary for researcher and industrial to construct 3D model with greater cost efficiency. The improvement of photography and computer vision has introduced the technique of SFM photogrammetry, an alternative in 3D model reconstruction other than TLS. Non-metric camera sensor mounted inside budget smartphone are used to capture images of stockpile and processed by Agisoft Metashape Professional (AMP) software to construct a 3D model. The volumetric measurement is executed and compare with the benchmark which is the model constructed from TLS. Statistics and tables are used to indicate the accuracy of Smartphone based SFM photogrammetry in intuitive manner. The result shows that the volumetric measurement by using smartphone SFM method has significant difference when compared with the benchmark, TLS solution.

ПРОВЕДЕНИЕ КАЛИБРОВКИ НЕМЕТРИЧЕСКОЙ ФОТОКАМЕРЫ В БЕСПИЛОТНОМ ЛЕТАТЕЛЬНОМ АППАРАТЕ ПРИ МОНИТОРИНГЕ ЗЕМЕЛЬ

Recently, unmanned aerial vehicles (UAVs) have been widely used in our country and in the world. This is due to continuity, endurance, the ability to work under overload conditions and the exclusion of the human factor. In recent years, there has been a revolutionary leap in the development of UAVs, which made it possible to divide this market segment into completely different price categories. The increase in the use of UAVs has made this product really in demand and was able to introduce it into various areas of life. This also applies to geodetic measurements. Photogrammetry methods began to work closely with methods of easy-to-control unmanned aerial vehicles. But at the same time, the demand for filming equipment is growing, the pricing policy of which sometimes considerably exceeds the cost of the aircraft itself, which complicates photogrammetric work. This aspect has led to research on the possibility of using inexpensive non-professional cameras on UAVs for photogrammetry, due to obtaining accurate measurements. For such cameras, there is such a thing as calibration, which includes the definition of interior orientation elements. This article discusses the use of non-metric cameras on UAVs in order to reduce the cost of work to monitor agricultural land. The following materials were used as initial data in this work: test images from the UAV at the test site; software such as SAS.Planet, MatLAb, MdCockpit V2.6.2.6, PHOTOMOD. To perform this work, the following equipment was used: unmanned aerial vehicle; non-metric digital camera. To calibrate the camera, the terrain was surveyed using Zala 421-21.

Evaluation of the Quality of a Checkerboard Camera Calibration Compared to a Calibration on a Laboratory Test Field

For photogrammetric works, a fundamental issue is the determination of camera internal orientation parameters (IOP). Without camera calibration, it is difficult to imagine a correct adjustment of the image network. Many industries use non-metric cameras, ranging from automatics and robotics, to heritage inventories, and the increasingly popular social mapping phenomenon uses low-budget cameras. Many different calibration methods exist, but dedicated calibration fields are commonly replaced by fast in-plane calibration with regular patterns. The main goal of this research is to verify the thesis that calibrating cameras on a checkerboard gives worse results in determining IOP than on a laboratory test field which may translate into the resulting model. For the purpose of this study, a special field was constructed, allowing calibration of the instruments on the basis of the network solution by the bundle adjustment. Unlike classical 2D fields, the field is equipped with a cork background providing a good base for matching and automatically detecting measurement marks. Calibration results were compared with calibration performed on a checkerboard implemented in MATLAB Camera Calibration Toolbox. In order to determine IOP in MATLAB, images of the checkerboard must be taken in such a way, that the whole pattern fits into the frame, otherwise toolbox defines the incorrectly coordinate system, which has a bad impact on calibration results. Moreover, the determined parameters have several times larger standard deviations than those determined in the laboratory test field, which confirms the thesis.

Photogrammetric Modelling of Street Conditions Using A Vehicle-mounted Non-metric Camera

Monitoring and modeling pavement distresses can employ either simple methods like direct measurements by tapes or straight edges, or more sophisticated approaches like laser scanners and stereoscopic cameras held at the ends of fixed poles. This study aims to detect pavement distress’s shape and position, such as cracks. For this purpose, overlapped images were collected for the distressed area to obtain complete coverage of the street conditions located in front of the College of Engineering /University of Duhok. Kurdistan Region, Iraq. A single non-metric camera attached to the side and the front of the vehicle is the approach employed as an image-collecting device. The camera shutter speed is selected to have a sequence of overlapped images to be processed, producing the pavement surface orthomosaic. The plane of the image in this study is inclined or obliquely relative to the pavement surface, so a gap is expected in the overlap area in the near range. To overcome this drawback and other problems, an indoor grid and tiles test was conducted to obtain the required parameters such as focal length, overlap percentage, camera shutter speed, and vehicle speed.   Ground control points (GCPs) and checkpoints for processing and accuracy checks were provided in each test and distributed evenly in the model area. The indoor parameter collecting tests revealed that the Root Mean Square Error (RMSE) for the (15) checkpoints was ±0.013m in X and ±0.016m in Y coordinates. Using a larger tilt angle and increasing camera height gave a root mean square error of ±0.009m in X and ±0.013m in Y, respectively. Image processing was conducted using Agisoft PhotoScan as it provided adequate accuracy and modeling tools in several previous papers

Defining The Relationship Between The Diameters of The Points Used in 2D Test Platforms and The Parameters Obtained from Camera Calibration

With the developing technology in recent years, there has been a significant increase in 3D spatial data needs and data production. 3D spatial data occupy an essential place in almost every field. As a result, there is a need for 3D spatial data production and the produced data's reliability. Like all spatial measuring equipment, cameras, which are data production units used in photogrammetry, must also be calibrated to produce reliable data. Calibration for non-metric cameras is critical to ensure that the measurements made are of high accuracy and at standards acceptable to everyone. In this study, to determine the factors affecting the calibration, terrestrial photogrammetric images were taken with a Canon EOS 600D non-metric camera with different point diameters on the calibration paper. These images were evaluated in the camera calibration software, and the photogrammetric result accuracies were investigated. The effects of the point diameters on the camera calibration paper on the calibration results have been observed. For both calibration papers, A4, A3, A0 sizes were printed and calibrated. As a result of the printouts, as can be predicted, the largest point sizes are A0, which has the largest paper size, and according to the results, it was seen that the highest accuracy was achieved in the A0 dimension. The relationship between the accuracy obtained in the calibration process and the point diameters in the test area was examined in this study. When the 144-point test area presented by the software is printed in A0 size, the point diameters were measured as 1.00 cm. In this study, calibration processes were performed as 1.00 cm, 1.20 cm, 1.40 cm, 1.60 cm, 1.80 cm and 2.00 cm by enlarging the point diameters by 20%, and more accurate results were obtained more easily than other paper sizes and calibration methods. As a result, since the calibration of the device to be used in the studies directly affects the accuracy of the model to be obtained at the end of the study, it is necessary to take the maximum accuracy obtained in the calibration process. In this research, the calibration process's highest accuracy is aimed and how the calibration process can be performed more effortless and more accurately by increasing the size of the point diameter on the test area.

Integration of Lidar system, mobile laser scanning (MLS) and unmanned aerial vehicle system for generation of 3d building model application: A review

Nowadays, 3D modelling has become very important because real information can be extracted from the model. UAV is system that was used for developing the 3D model and has proven capable to produce good results. However, the exploration of the integration of UAV with other technology like LiDAR and MLS to develop a more accurate and detailed model is still lacking. This study reviews the aptitudes of the UAV integrated with LiDAR and MLS for developing the 3D building model in Malaysia. Several issues, like type of platform, quality of 3D model and others to review the capabilities of the UAV used for producing very accurate 3D model were critically analysed. Previous research suggests that integration of Lidar with multi-rotor platform fusing with MLS could be used to construct an accurate 3D model. A dense point cloud of the whole building can be obtained from the fusion between Lidar and MLS. Moreover, an accurate 3D model can be generated from this process as the point-cloud from LiDAR and MLS has positional accuracy in centimetre level compared to a non-metric camera integrated with a UAV. This study finds the UAV has the potential to use to produce a quality 3D model.

3D Modelling of Meteorite from Astomulyo Village, Lampung, Indonesia by Close Range Photogrammetry (CRP) Methods

This research was conducted to 3D model our meteorite collection based on photo-capturing. This meteorite are from Astomulyo, Central Lampung, Indonesia. It entry the earth's atmosphere and was found on January 28, 2021. The chance of object degradation nearly appears over time, so It is very urgent to obtain the 3D model of the object for further research necessary. 3D modelling was carried out using a non-metric camera to conduct the close-range photogrammetry method. It applies to modelling the objects based on photo data using the concept of collinearity by using a central projection system on the camera to record. The collinearity will produce an object point between the camera center and the object cloud point. Hence, this process forms the object model from the appropriate image projection, the tie point with the triangular irregular network model. As a result, it produces the DTM (Digital Terrain Model) object formation using stand-alone photogrammetric software, raster graphics, and 3D modelling software.

Acceleration of Human Resource Development for the UAV data processing in Indonesia

Abstract. Geospatial Information (GI) utilization needs acceleration in conjunction with the unprecedented improvement of GI technology infrastructures. Unmanned Aerial Vehicles (UAV) is one instance that demonstrates some advantages by enabling on demand flexible geospatial data acquisition. However due to the frequent use of non-metric camera such as consumer grade cameras, it requires the calibration procedure in order to fulfil the acceptable geometrical accuracy. The relatively simple procedures and high resolution produced data are the major advantages of the UAV data acquisition. With a land area approximately five times of the Federal Republic of Germany, the provision of GI in Indonesia requires innovative acceleration strategies that also considers cost production efficiency moreover due to the preparation of human resource in GI as its primary component. In this case, certification and accreditation in GI area are still mandatory especially in conjunction with technological improvements and weather situation (cloud coverage) as the main constraints to be considered for the geodata acquisition in Indonesia. This process includes knowledges, skills and/or advancements as well as working behaviour relevant with the tasks and conditions in a so-called Competency Working Standards of Indonesia (SKKNI). In addition to the SKKNI, GI competency standards can also use relevant international standards or specific standards as a reference. Competency standards are the basic requirements for any activities related with the national GI provision. Based on analysis of the national interests, the qualification identifications can be performed by specific study in the context of business process and GI industry from the scope of above mentioned national/international view as well as particular (GI) industry.Finally, this paper discusses and formulates the competency standards that can be used by corresponding stakeholders involved in the national GI provision from the actual regulation as well as technological/industrial perspectives. The standards of GI empowerments are fundamental especially in a situation where there are various technology and method available in the society as well as GI industry. For this purpose, the proper professional certification must be essentially well defined in order to prepare excellent GI human resources as the primary source for the provision of reliable GI data and information in a favour of the Large Scale Topographic Mapping (LSTM) and Updating acceleration program.

Photogrammetric Precise Surveying Based on the Adjusted 3D Control Linear Network Deployed on a Measured Object

In surveying engineering tasks, close-range photogrammetry belongs to leading technology by considering different aspects like the achievable accuracy, availability of hardware and software, accessibility to measured objects, or the economy. Hence, constant studies on photogrammetric data processing are desirable. Especially in industrial applications, the control points for close-range photogrammetry are usually measured using total stations. In the case of smaller items, more precise positions of control points can be obtained by deploying and adjusting a three-dimensional linear network located on the object. This article analyzes the accuracy of the proposed method based on the measurement of the linear network using a professional tape with a precision of ±1 mm. It is shown what accuracy of object feature dimensioning can be obtained based on the proposed innovative network method for photo-point measurement, using only the minimum required number of two stereo-images. The photogrammetric 3D model derived from them and captured with a non-metric camera is characterized by the highest possible precision, which qualifies the presented approach to accurate measurements used in the surveying engineering. The authors prove that the distance between two randomly optional points derived from the 3D model of a dimensioned object is equal to the actual distance measured directly on it with one-millimeter accuracy.

Non-Measuring Camera Monitoring of Comprehensive Displacement of Simulated Slope Mass Based on Edge Extraction of Subpixel Ring Mark

Slope hazards threaten the safety of buildings and people’s lives and property. Real-time and dynamic monitoring of slope deformation by digital image monitoring technology is an effective method to prevent slope hazards. In this study, the Zhang Zhengyou calibration method is used to calibrate a non-metric digital camera, which is used to monitor the simulated slope with ring marks. The sub-pixel algorithm is used to identify the center coordinates of the landmarks. The proportional coefficient is obtained from the relationship between the landmarks and the actual distance. The change in displacement of the position of the digital camera is calculated in combination with the specific displacement value of the slope, yielding the rapid and accurate displacement trend of the slope. The outdoor experimental results show that the monitoring accuracy of this method can reach millimeter level, which can meet the demand of slope monitoring.

A novel design concept of cost-effective permanent rail-track monitoring system

This paper presents a novel design concept of low-cost permanent monitoring system for rail-track problems. The introduced design is theoretically overcome the currant in-use designs in terms of providing permanent accurate observations for detecting rail-track irregularities for all railway network during service time using low-cost integrated sensors. The paper investigates the rail-track common irregularities by identifying the issues, presenting challenges, and highlighting the limitations of currently in-use rail-track monitoring techniques. Then, the potential of using cost-effective sensors and intelligent techniques for detecting the rail-track geometric parameters and rail irregularities is theoretically studied. This includes using low-cost GPS, MEMS-INS & high frequency single-point and multi-spot laser distance sensors for detecting rail surface cracks, fractures, cross-level, wrap, gauge and vertical & horizontal rail alignments. Different levels of GPS/MEMS-INS integration are covered, illustrating the advantages of each solution and the optimal utilization in the system. Vision-based monitoring using low-cost HD non-metric digital cameras is also investigated, showing the optimal specifications required for fulfill the system requirements. Data logging and GPS-time-based synchronization method is presented as a part of the design concept of the suggested system. The processing techniques and unit outputs are illustrated in details, showing how each unit works for detecting the rail-track irregularities, providing the geodetic positioning and the vision-based assessing. The main part of the system, which is Automatic Adjusted Wheeled Carrier Frame (AAWCF) is discussed in more details, showing simple and clear different views for all details and integrated sensors. It is recommended to carry out this idea, by building up and evaluating the performance of AAWCF in real railway environments, evaluating the design concept of each unit individually to know the weaknesses of each technique, and then evaluating the whole system in all expected railway cases to find out the advantages and limitations of this design concept.