Academic literature on the topic 'Nikkorex camera'

This paper proposes a technique to estimate the distance between an object and a rolling shutter camera using a single image. The implementation of this technique uses the principle of the rolling shutter effect (RSE), a distortion within the rolling-shutter-type camera. The proposed technique has a mathematical strength compared to other single photo-based distance estimation methods that do not consider the geometric arrangement. The relationship between the distance and RSE angle was derived using the camera parameters (focal length, shutter speed, image size, etc.). Mathematical equations were derived for three different scenarios. The mathematical model was verified through experiments using a Nikon D750 and Nikkor 50 mm lens mounted on a car with varying speeds, object distances, and camera parameters. The results show that the mathematical model provides an accurate distance estimation of an object. The distance estimation error using the RSE due to the change in speed remained stable at approximately 10 cm. However, when the distance between the object and camera was more than 10 m, the estimated distance was sensitive to the RSE and the error increased dramatically.

Damage caused by misapplication of herbicides in landscape management or drift from agricultural fields on to nearby landscape plantings is often difficult to diagnose. Symptoms may vary with herbicide, species that is damaged, and other factors. To address this need, a photo CD-ROM has been developed to help plant damage diagnosticians determine if damage has been caused by herbicides. Fourteen herbicides or herbicide combinations commonly used in turfgrass, landscape, or field crop production applications were applied to 21 taxa of landscape trees, shrubs, groundcovers, or herbaceous perennials. More than 800 photographic transparencies of damage symptoms (representing all 21 taxa and 12 herbicides) were taken, and 457 were selected for storage in the digitized photo CD format for rapid retrieval. In all cases, as damage symptoms were observed, they were photographically recorded using a Nikon FM camera with a 55-mm micro-NIKKOR lens and Fujichrome Velvia transparency film under ambient, sunlit conditions. Species and plant taxa lists are displayed and the CD-ROM is demonstrated.

This paper presents results from a Direct Mapping Solution (DMS) comprised of an Applanix APX-15 UAV GNSS-Inertial system integrated with a Sony a7R camera to produce highly accurate ortho-rectified imagery without Ground Control Points on a Microdrones md4-1000 platform. A 55 millimeter Nikkor f/1.8 lens was mounted on the Sony a7R and the camera was then focused and calibrated terrestrially using the Applanix camera calibration facility, and then integrated with the APX-15 UAV GNSS-Inertial system using a custom mount specifically designed for UAV applications. <br><br> In July 2015, Applanix and Avyon carried out a test flight of this system. The goal of the test flight was to assess the performance of DMS APX-15 UAV direct georeferencing system on the md4-1000. The area mapped during the test was a 250 x 300 meter block in a rural setting in Ontario, Canada. Several ground control points are distributed within the test area. The test included 8 North-South lines and 1 cross strip flown at 80 meters AGL, resulting in a ~1 centimeter Ground Sample Distance (GSD). <br><br> Map products were generated from the test flight using Direct Georeferencing, and then compared for accuracy against the known positions of ground control points in the test area. The GNSS-Inertial data collected by the APX-15 UAV was post-processed in Single Base mode, using a base station located in the project area via POSPac UAV. The base-station’s position was precisely determined by processing a 12-hour session using the CSRS-PPP Post Processing service. The ground control points were surveyed in using differential GNSS post-processing techniques with respect to the base-station.

<p><strong>Abstract.</strong> The survey of ancient cave can generally be performed by traditional topographic methods that allow also its georeferencing in a global reference frame; some difficulties may arise when there are narrow tunnels that do not consent the use of a total station or a terrestrial laser scanner. In such cases a visual-based approach can be used to produce, both the followed path and the 3D model of the hypogeal environment. A prompt photogrammetric survey has been used to reconstruct the morphology of the La Sassa Cave, situated in the municipality of Sonnino (Latina), in the lower Lazio region. In this cave, a very large quantity of Pleistocene animal bones was found, together with several fragments of Copper Age human bones and Bronze Age impasto potsherds.</p><p> The survey was carried out using a DSLR full frame camera Nikon D800E with a Nikkor 16<span class="thinspace"></span>mm fisheye lens pre-calibrated. During the acquisition, several targets were measured in order to contain the deformations model. The photogrammetric model has been georeferenced using 3 GCPs positioned outside the cave entrance where a double frequency GNSS receiver has acquired data in static session mode.</p>

Efficient mapping from unmanned aerial platforms cannot rely on aerial triangulation using known ground control points. The cost and time of setting ground control, added to the need for increased overlap between flight lines, severely limits the ability of small VTOL platforms, in particular, to handle mapping-grade missions of all but the very smallest survey areas. Applanix has brought its experience in manned photogrammetry applications to this challenge, setting out the requirements for increasing the efficiency of mapping operations from small UAVs, using survey-grade GNSS-Inertial technology to accomplish direct georeferencing of the platform and/or the imaging payload. The Direct Mapping Solution for Unmanned Aerial Vehicles (DMS-UAV) is a complete and ready-to-integrate OEM solution for Direct Georeferencing (DG) on unmanned aerial platforms. Designed as a solution for systems integrators to create mapping payloads for UAVs of all types and sizes, the DMS produces directly georeferenced products for any imaging payload (visual, LiDAR, infrared, multispectral imaging, even video). Additionally, DMS addresses the airframe’s requirements for high-accuracy position and orientation for such tasks as precision RTK landing and Precision Orientation for Air Data Systems (ADS), Guidance and Control. <br><br> This paper presents results using a DMS comprised of an Applanix APX-15 UAV with a Sony a7R camera to produce highly accurate orthorectified imagery without Ground Control Points on a Microdrones md4-1000 platform conducted by Applanix and Avyon. APX-15 UAV is a single-board, small-form-factor GNSS-Inertial system designed for use on small, lightweight platforms. The Sony a7R is a prosumer digital RGB camera sensor, with a 36MP, 4.9-micron CCD producing images at 7360 columns by 4912 rows. It was configured with a 50mm AF-S Nikkor f/1.8 lens and subsequently with a 35mm Zeiss Sonnar T* FE F2.8 lens. Both the camera/lens combinations and the APX-15 were mounted to a Microdrones md4-1000 quad-rotor VTOL UAV. The Sony A7R and each lens combination were focused and calibrated terrestrially using the Applanix camera calibration facility, and then integrated with the APX-15 GNSS-Inertial system using a custom mount specifically designed for UAV applications. The mount is constructed in such a way as to maintain the stability of both the interior orientation and IMU boresight calibration over shock and vibration, thus turning the Sony A7R into a metric imaging solution. <br><br> In July and August 2015, Applanix and Avyon carried out a series of test flights of this system. The goal of these test flights was to assess the performance of DMS APX-15 direct georeferencing system under various scenarios. Furthermore, an examination of how DMS APX-15 can be used to produce accurate map products without the use of ground control points and with reduced sidelap was also carried out. Reducing the side lap for survey missions performed by small UAVs can significantly increase the mapping productivity of these platforms. <br><br> The area mapped during the first flight campaign was a 250m x 300m block and a 775m long railway corridor in a rural setting in Ontario, Canada. The second area mapped was a 450m long corridor over a dam known as Fryer Dam (over Richelieu River in Quebec, Canada). Several ground control points were distributed within both test areas. <br><br> The flight over the block area included 8 North-South lines and 1 cross strip flown at 80m AGL, resulting in a ~1cm GSD. The flight over the railway corridor included 2 North-South lines also flown at 80m AGL. Similarly, the flight over the dam corridor included 2 North-South lines flown at 50m AGL. The focus of this paper was to analyse the results obtained from the two corridors. <br><br> Test results from both areas were processed using Direct Georeferencing techniques, and then compared for accuracy against the known positions of ground control points in each test area. The GNSS-Inertial data collected by the APX-15 was post-processed in Single Base mode, using a base station located in the project area via POSPac UAV. For the block and railway corridor, the basestation’s position was precisely determined by processing a 12-hour session using the CSRS-PPP Post Processing service. Similarly, for the flight over Fryer Dam, the base-station’s position was also precisely determined by processing a 4-hour session using the CSRS-PPP Post Processing service. POSPac UAV’s camera calibration and quality control (CalQC) module was used to refine the camera interior orientation parameters using an Integrated Sensor Orientation (ISO) approach. POSPac UAV was also used to generate the Exterior Orientation parameters for images collected during the test flight. <br><br> The Inpho photogrammetric software package was used to develop the final map products for both corridors under various scenarios. The imagery was first imported into an Inpho project, with updated focal length, principal point offsets and Exterior Orientation parameters. First, a Digital Terrain/Surface Model (DTM/DSM) was extracted from the stereo imagery, following which the raw images were orthorectified to produce an orthomosaic product.

Efficient mapping from unmanned aerial platforms cannot rely on aerial triangulation using known ground control points. The cost and time of setting ground control, added to the need for increased overlap between flight lines, severely limits the ability of small VTOL platforms, in particular, to handle mapping-grade missions of all but the very smallest survey areas. Applanix has brought its experience in manned photogrammetry applications to this challenge, setting out the requirements for increasing the efficiency of mapping operations from small UAVs, using survey-grade GNSS-Inertial technology to accomplish direct georeferencing of the platform and/or the imaging payload. The Direct Mapping Solution for Unmanned Aerial Vehicles (DMS-UAV) is a complete and ready-to-integrate OEM solution for Direct Georeferencing (DG) on unmanned aerial platforms. Designed as a solution for systems integrators to create mapping payloads for UAVs of all types and sizes, the DMS produces directly georeferenced products for any imaging payload (visual, LiDAR, infrared, multispectral imaging, even video). Additionally, DMS addresses the airframe’s requirements for high-accuracy position and orientation for such tasks as precision RTK landing and Precision Orientation for Air Data Systems (ADS), Guidance and Control. <br><br> This paper presents results using a DMS comprised of an Applanix APX-15 UAV with a Sony a7R camera to produce highly accurate orthorectified imagery without Ground Control Points on a Microdrones md4-1000 platform conducted by Applanix and Avyon. APX-15 UAV is a single-board, small-form-factor GNSS-Inertial system designed for use on small, lightweight platforms. The Sony a7R is a prosumer digital RGB camera sensor, with a 36MP, 4.9-micron CCD producing images at 7360 columns by 4912 rows. It was configured with a 50mm AF-S Nikkor f/1.8 lens and subsequently with a 35mm Zeiss Sonnar T* FE F2.8 lens. Both the camera/lens combinations and the APX-15 were mounted to a Microdrones md4-1000 quad-rotor VTOL UAV. The Sony A7R and each lens combination were focused and calibrated terrestrially using the Applanix camera calibration facility, and then integrated with the APX-15 GNSS-Inertial system using a custom mount specifically designed for UAV applications. The mount is constructed in such a way as to maintain the stability of both the interior orientation and IMU boresight calibration over shock and vibration, thus turning the Sony A7R into a metric imaging solution. <br><br> In July and August 2015, Applanix and Avyon carried out a series of test flights of this system. The goal of these test flights was to assess the performance of DMS APX-15 direct georeferencing system under various scenarios. Furthermore, an examination of how DMS APX-15 can be used to produce accurate map products without the use of ground control points and with reduced sidelap was also carried out. Reducing the side lap for survey missions performed by small UAVs can significantly increase the mapping productivity of these platforms. <br><br> The area mapped during the first flight campaign was a 250m x 300m block and a 775m long railway corridor in a rural setting in Ontario, Canada. The second area mapped was a 450m long corridor over a dam known as Fryer Dam (over Richelieu River in Quebec, Canada). Several ground control points were distributed within both test areas. <br><br> The flight over the block area included 8 North-South lines and 1 cross strip flown at 80m AGL, resulting in a ~1cm GSD. The flight over the railway corridor included 2 North-South lines also flown at 80m AGL. Similarly, the flight over the dam corridor included 2 North-South lines flown at 50m AGL. The focus of this paper was to analyse the results obtained from the two corridors. <br><br> Test results from both areas were processed using Direct Georeferencing techniques, and then compared for accuracy against the known positions of ground control points in each test area. The GNSS-Inertial data collected by the APX-15 was post-processed in Single Base mode, using a base station located in the project area via POSPac UAV. For the block and railway corridor, the basestation’s position was precisely determined by processing a 12-hour session using the CSRS-PPP Post Processing service. Similarly, for the flight over Fryer Dam, the base-station’s position was also precisely determined by processing a 4-hour session using the CSRS-PPP Post Processing service. POSPac UAV’s camera calibration and quality control (CalQC) module was used to refine the camera interior orientation parameters using an Integrated Sensor Orientation (ISO) approach. POSPac UAV was also used to generate the Exterior Orientation parameters for images collected during the test flight. <br><br> The Inpho photogrammetric software package was used to develop the final map products for both corridors under various scenarios. The imagery was first imported into an Inpho project, with updated focal length, principal point offsets and Exterior Orientation parameters. First, a Digital Terrain/Surface Model (DTM/DSM) was extracted from the stereo imagery, following which the raw images were orthorectified to produce an orthomosaic product.

The study of flow and transport in porous media has relevance in many industrial, environmental (Geologic sequestration of CO2) and biological disciplines. In many engineering applications we require the knowledge of the velocity field for flow through porous objects. Historically, simplified models such as Darcy’s law [1,2], provide a reasonable description of the flow in the interior for single phase flow but require empirical coefficients to match the boundary conditions with the outer flow. The scientific basis for understanding flow and transport phenomena in porous media has largely been developed from experimental and theoretical studies in “bulk” or macroscopic systems in which coupled behavior at the pore scale is not measured or observed directly. To understand the flow behavior at the pore scale, flow characterization in porous media is very important. Multiphase, immiscible, low Re flow through a simulated porous media is studied experimentally. The experimental test cell, Figure 1, designed in collaboration with the Department of Energy, National Energy Technology Laboratory (DOE NETL), was manufactured from an optically clear polycarbonate material. It has a lattice type pattern of 2.5 mm pores bodies interconnected by angular capillary throats varying in size from 200 μm to 1000 μm. The experimental flow loop (Figure 2), utilizes air as the displacing fluid and sodium iodide (NaI) solution in water as the defending fluid. Air is provided at a constant pressure at the inlet. The refractive indices of the NaI solution and the optically clear test cell are matched to facilitate the observance of the air-liquid interface motion. Experimental data recorded with respect to time are the inlet gage pressure, delta pressure, inlet to outlet, across the test cell, volume flow rate at the outlet and the position of the displacement interface as the invading fluid, air, displaces the defending fluid, NaI solution. Parameters that can be varied in the experiment are viscosity ratio, micro and macro capillary number, the bond number and the volume flow rate. The details of the test loop are provided in Figure 2. The figure shows the piping arrangement to fill the test cell with the NaI solution and supplying the air for the tests. A CCD camera (Redlake ES 1.0 cross-correlation camera; resolution: 1008 × 1018 pixels) equipped with a 20 mm Micro Nikkor lens (Nikon) and a data acquisition system consisting of a PC and a PIXCI D2X frame grabber card (EPIX) is utilized to obtain a series of digital images as the invading air enters the test cell through the inlet manifold and makes way through the liquid until the breakthrough to the exit manifold. The pore scale velocity of the displacement interface is determined using a “Difference Threshold Technique” developed at Case Western Reserve University (CWRU), Laser Flow Diagnostics Lab (LFDL), Department of Mechanical and Aerospace Engineering. The difference threshold technique developed to processing the images is described in the next section.