Muhd. Safarudin Chek Mat #1,Nazirah Md Tarmizi #2, Mokhtar Azizi Mohd Din *3, Abdul Manan Samad #2

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1 2014 IEEE 4th International Conference on System Engineering and Technology (ICSET) November 24-25, 2014 Bandung - Indonesia Application of UAiCs for Quarry Determination and Spatial Analysis Muhd. Safarudin Chek Mat #1,Nazirah Md Tarmizi #2, Mokhtar Azizi Mohd Din *3, Abdul Manan Samad #2 #1,2,4 Pixelgrammetry & Al-Idrisi Research Group (Pi_ALiRG) Department Centre of Studies Surveying Science & Geomatics, Faculty of Architecture, Planning & Surveying; Universiti Teknologi MARA, Shah Alam Campus, Malaysia 1 nazirahtarmizi119@gmail.com 2 dr_abdmanansamad@ieee.org *3 Faculty of Civil Engineering, Universiti Malaya, Kuala Lumpur, Malaysia Abstract This paper investigate the potential of Unmanned aerial imagery capturing system(uaics) to mapping a quarry area and carried out area measurement and spataial analysis. This study used fixed wing UAiCs as a platform and a sensor compact camera Canon PowerShot SX230 HS. A workflow from flight planning, data acqusistion and data processing was demonstrates in this research. Two result was produced which is digital orthophoto and digital elelvation model(dem). Based on the result, contour was generated. Besides the volume, area and perimeter for total area, current excavation and balanced area are discussed. Keywords UAiCs, Quarry area measurement, Orthophoto, DEM, Volume. I. INTRODUCTION Unmanned aerial imagery capturing system (UAiCs) describes photogrammetric measurement platforms, which operate as either remotely controlled, semi-autonomously, or autonomously, without unmanned on the platform. The broad definition covers balloons, kites, gliders, airships, rotary and fixed wing UAVs with the capability for photogrammetric data acquisition in manual, semi-automated and automated flight mode [1]. UAiCs indicate the platform, sensor hardware, software and connection which intergrate together to builds a system for aerial mapping. The aerial photogrammetry is more related to mapping, environmental studies and etc. The topographic map can be prepared at a given standard of accuracy from aerial photograph. Under most conditions, particularly for large area, aerial photogrammetric techniques are less expensive than purely ground surveying techniques[2]. UAiCs technology is still new, but it has the potential towards various applications.the quarry industry is integral to the construction industry. Its growth is in tandem with the growth of the Malaysian economy and the construction sector. One of the main issues that is affecting the industry is the impact of quarry activities on the environment as well as the surrounding residential areas[3]. A tool is needed to monitor and study this area. The spatial and temporal resolution obtained from the acquired UAV images together with the automation level achieved by open source tools, allow us to aspire to high quality, immediate and low-cost geomatic products[4]. This paper will utilize the potential of application of UAiCs in quarry area for measurement and spatial analysis. A. Study Area II. STUDY AREA AND UAV SYSTEM The area over which imagery was acquired was located at northern state of Malaysia, Bukit Chuping, Perlis with an area about sq. km. The height of the hill is almost 315m above the mean sea level. The UAiCs missions were acquired in June of B. Platform and Sensor 1) Unmanned Aerial Imagery Capturing System (UAiCs) Fig. 1 Pi_ALiRG UAiCs before take-off /$ IEEE

2 Fixed wing UAiCs named as Pi_AliRG UAiCs used in this study equipped with a big fuselage radio controlled model plane, GPS receiver, a miniature autopilot and a compact digital camera. The weight about 2.5kg, Pi_AliRG UAiCs will fly according to the flight path and the camera performs automatically to take GPS based digital imagery at every 3 seconds. 2) Sensor Canon PowerShot SX230 HS has been used in data acquisition. Equipped with 6.17 x 4.55mm sensor size, 12.1 megapixel back-illuminated CMOS sensor, DIGIC 4 image processing engine and image stabilizer. The Canon PowerShot SX230 HS also has built-in GPS. The weight just about 223g including battery make it an efficient sensor to attach in UAiCs carrier. III. METHODOLOGY The workflow of this research (Fig. 2) involves in this research activity to obtain the final output of this research. Selection of the study area. Selection of instruments. Planning Stage Camera Calibration. Flight Planning (Coverage area, flying height, sidelap & endlap, GCPs locations, weather conditions, scheduling and cost estimating) Set up a ground base station. (Launching, landing, monitoring location) A. Planning Stage The planning stage is the key to the success of the aerial photogrammetric mission. Planning must be performed by experienced and knowledgeable with thorough study prior to proceeding the flight mission. The most important is to decide the final data that will be produced. The location coverage, then will be better suited with the data needed. Camera calibration is an important phase for non - metric cameras as being a necessary element of photogrammetric assessment. The purpose of camera calibration is to determine the focal length, principal point, and lens distortion from the camera[5]. This process is needed to figure out the unstable element in the camera like interior orientation and lens distortion parameters. Besides, the camera parameters such as focal length is needed to flight mission as well as pixel size of the camera is used to estimate each size of the image. The ground coverage area of one image can be calculated by using resolution dimension, pixel size and scale[6]. Apart from that, the coverage also considers the ability of UAiCs can perform. In this study, the coverage of area involved high elevation terrain, the peak of the hill is more than 300meter. APM software, Mission Planner is used to design the flight path. Based on optimum sensor and UAiCs specification calculated, flying height is set to 500meter. Pi_ALiRG UAiCs was capable to fly within 1 hour 15 minutes. The flying speed is set-up to 40km/h but the speed of UAiCs is changing because of uncertainty wind in the air. However, the speed set-up is the befitting for the flight mission. An initial set-up of flight path would imply the post reference for flight planning involves with flying height, coverage area, scale, percentage of side lap and end lap[7]. Telemetry checking. Data Acquisition On screen flight path telemetry monitor. Images captured checking and stored. Import images in software. Extract EXIF data from images. Data Processing Align Photos, Build Geometry and Build Texture. Fig. 3 Canon PowerShot SX230 HS as a sensor. Generate Orthophoto and DEM. Fig. 2 Workflow of study. Preparation of ground control point (GCP) locations also be taken into planning. Although this study is collected the GCPs by post marking, the rough ideas to locates the ground control at first planned using Google Earth. This helps us to understand better the study area and help accelerate the process of taking GCPs to save time. The well distribute

3 locations of GCPs in the coverage area then were measured using Garmin GPS. B. Data Acquisition The ground base station is set-up on the flight mission day. The location of the ground base station must be clear from obstacles as high building, substation, trees, and any features that will disrupt a launching and landing of UAiCs. This study was chosen field area to set-up ground base station. The field area is one of the best sites that reduce the risk of UAiCs launching and landing from impacts. Spacious area also helps to give a good telemetry to monitor UAiCs. The preparation of UAiCs of sites before launching is compulsory. All systems in UAiCs must be properly checked and functional. Connection and configuration checking involved with autonomous chipset, global positioning system, radio modem, battery power and electronic speed controller. The flight planning designed in the computer then will be transferred to autonomous chipset in UAiCs. The computer program will receive a completed data of UAiCs. Although the UAiCs is an autonomous flight, launching and landing usually operated by professional. The operator needs to check the motion sensor of the UAV such as rudder, elevator and throttle before ready to take-off. The UAiCs usually manually operated at launching base until it reaches a safe altitude. The autonomous mode, then activated and were monitored on screen. The sensor of this study was programmed to capture the image about 3 second intervals. At landing time, the operator will hand a UAiCs when the flight back to ground base. Landing time requires high skill and experiences operator to ensure UAiCs is land safely without any impact which could damage the platform and sensor. The data acquisition stored in sensor memory thereupon is transferred to computer for verification of the images quality and quantity at the site. C. Data Processing All the images acquired again checked and was selected based on the quality. There are 1049 images acquired from this study. Blurred and too much exposure images must be avoided because it will interfere the processing progress later. Better quality images will provide reliable and an accuracy data. All the images taken was processed using Agisoft Photoscan. Agisoft Photoscan involved with several processes, workflows. First, loading the images indicate photographs that will be used for further processing. The images loaded can be inspected and remove unnecessary images. Exchangeable file format (EXIF) logs data from all images was extracted to the programme. It contains the GPS coordinate position x, y and z, time and ancillary tags while the images were taken. Next is to identify camera calibration parameters. Default programme assumed the focal length of the camera, 50mm (35mm film equivalent) if the EXIF metadata insufficient. It is also estimates both internal and external camera orientation parameters, including nonlinear radial distortions. This can cause failure in alignment process where the parameters does not fit the actual parameters of the sensor. In producing a reliable data, it is required to specify camera calibration manually. Once the images loaded into the program, the images need to be aligned. The camera position is determined based on sensor GPS data and the system then builds a points cloud model. The process takes about 4 hours using computer with processor Intel Core i GB installed RAM, and NVidia GeForce GT 630 graphic card. Fig. 4 Completed point cloud model. After completing the alignment processed. The calculated position of the camera and point cloud is displayed in the software. The alignment result needs to be inspected properly to remove incorrectly point cloud. The next process is to build model geometry. The most take time process because of intensive operation to obtain more detailed and accurate geometry. The process takes about 5 hours to finish. The last stage of processing is to build the texture model. In this stage, the software determines how the object texture will be rendered in the model. Proper texture helps to obtain optimal texture rendered and better visual quality of the final model. The result shown as (Fig. 5) Fig. 5 The model displayed after the texture process.

4 IV. RESULT There are two main results produced in this study, which is digital orthophoto and digital elevation model (DEM). The process of generation of digital orthophoto and DEM was done using Agisoft Photoscan. The result being displayed using Global Mapper software. Fig. 8 Contour generated based on the DEM. Fig. 6 Result of digital elevation model(dem) displayed. The contour was produced at 10meter intervals as shown in (Fig. 8). As a result, the excavation area shows contour between 0meter to 260meter. Besides, the area that has not been excavate or balanced area indicates a contour between 260meter to 310meter. The peak of the hill is recorded at meter. The second analysis was determined the measurement of the study area. Three measurements were made which are volume, area and perimeter based on total area, current excavation area, and balanced area. The measurement was made as shown in (Fig. 9). Digital orthophoto was used to identify the excavation area, then a total area located to find the balanced area of research study. Fig. 7 Result of digital orthophoto displayed. V. ANALYSIS AND DISCUSSION The aim of this study to investigate the quarry area measurement and spatial analysis based on digital orthophoto and DEM produced. First, the contour of the study area was generated from DEM produced, then the contour were layered on orthophoto for easy interpretation. Fig. 9 The measurement of study area. The result from the measurement recorded in Table 1. TABLE I THE MEASUREMENT OF BUKIT CHUPING Total Area Current Excavation Area Balanced Area Volume (m3) Area (m2) Perimeter (m)

5 Based on the result, the volume of the total area indicate m 3 while the volume for the current excavation area about m 3, so the volume for balanced area can be calculated and recorded at m 3. Besides, the area and perimeter also can be determined as shown in Table 1. The balanced area measurement is useful to predict the resources that can be used, while the authorities also can monitor the production of resources. VI. CONCLUSIONS In the conclusion, it has been shown that UAiCs fixed wings has the capability to produce quarry area measurement and spatial analysis. This study has produced two photogrammetric results which are digital orthophoto and DEM. The results then, were used to measure areas of interest for analysis. The total area in this study was covered sq. km. The potential ways of UAiCs to deliver a quicker data for following area is impressive. The quarry area changes routinely because of resource production carried out by the excavator everyday, this requires repeatedly information of the quarry area. Ability of UAiCs to produce quick and cost effective data is very useful for monitoring and analysing work. REFERENCES [1] H. Eisenbei, UAV Photogrammetry [2] A. Ahmad, K. A. Hashim, A. M. Samad, and U. T. Mara, Aerial Mapping using High Resolution Digital Camera and Unmanned Aerial Vehicle for Geographical Information System, pp , [3] W. Zulasmin and W. Ibrahim, Towards a Sustainable Quarry Industry in Malaysia Limestone and Granite Quarry Industry, no. December, [4] D. González-aguilera, J. Fernández-hernández, J. Mancera-taboada, P. Rodríguez-gonzálvez, and D. Hernández-, 3d Modelling and Accuracy Assessment of Granite Quarry Using Unmmanned Aerial Vehicle, vol. I, no. September, pp , [5] A. M. Samad, N. Kamarulzaman, M. A. Hamdani, T. A. Mastor, and K. A. Hashim, The potential of Unmanned Aerial Vehicle (UAV) for civilian and mapping application, 2013 IEEE 3rd Int. Conf. Syst. Eng. Technol., pp , Aug [6] K. N. Tahar, A. Ahmad, W. Abdul, A. Wan, and M. Akib, Full Length Research Paper A new approach on production of slope map using autonomous Unmanned aerial vehicle, vol. 7, no. 42, pp , [7] T. A. Mastor, N. A. Sulaiman, S. Juhairi and A. M. Samad, An Unmanned Aerial Imagery Capturing System ( UAiCs ): A Review of Flight Mission Planning, pp. 7 9, ACKNOWLEDGMENT Pixelgrammetry and Al-Idrisi Research Group (Pi_ALiRG); Green Technology & Sustainable Development (GTSD), UiTM-RMI Communities of Research (CoRe); UiTM Research and Management Institute (RMI-UiTM); Ministry of Higher Education (MOHE), UiTM DANA RESEARCH GRANT [600-RMI / DANA 5/3 CIFI (2/2013)] and Centre of Studies Surveying Science and Geomatics, Faculty of Architecture, Planning and Surveying, UiTM Shah Alam are greatly acknowledged.