Some Considerations in the Design of Low Cost Remotely-Piloted Aircraft for Civil Remote Sensing Applications

Early in 1982, B.C. Research began to evaluate the feasibility, advantages and limitations of using Remotely-Piloted Aircraft (RPA) to acquire aerial photography in environmental applications. Advantages associated with these aircraft include low costs, ease of operation, low noise levels, portability, safety and very low speed-low altitude capability. In the first phase of this program, a three-meter span fixed-wing aircraft was constructed from a commercial model kit and modified to carry a remotely-operated 35 mm camera system. In summer 1982, this system was used to acquire aerial photography in a variety of applications including forestry, pollution detection, wildlife habitat assessment, site mapping, publicity, wildlife inventories and shoreline mapping. Various operational limitations were encountered including difficulty of navigation and aircraft control, the fragility of the “model” airframe and its limited payload capability. These limitations are being addressed in Phase II of the program, during which a purpose-built airframe is under development, equipped with automatic flight controllers and emergency systems, and employing digitally-encoded radio signals for secure aircraft command. A black-and-white video camera installed in the airframe provides real-time imagery as an aid to navigation and photoframing.

Download Full-text

Application of Shore-Based Video and Unmanned Aerial Vehicles (Drones): Complementary Tools for Beach Studies

Remote Sensing ◽

10.3390/rs12030394 ◽

2020 ◽

Vol 12 (3) ◽

pp. 394 ◽

Cited By ~ 2

Author(s):

Donatus Bapentire Angnuureng ◽

Philip-Neri Jayson-Quashigah ◽

Rafael Almar ◽

Thomas Christian Stieglitz ◽

Edward Jamal Anthony ◽

...

Keyword(s):

Low Cost ◽

Video Camera ◽

Video Data ◽

Camera System ◽

Camera Systems ◽

Camera View ◽

Aerial Vehicle ◽

One Year ◽

Video Camera System ◽

Good Agreement

Video camera systems have been used over nearly three decades to monitor coastal dynamics. They facilitate a high-frequency analysis of spatiotemporal shoreline mobility. Video camera usage to measure beach intertidal profile evolution has not been standardized globally and the capacity to obtain accurate results requires authentication using various techniques. Applications are mostly site specific due to differences in installation. The present study examines the accuracy of intertidal topographic data derived from a video camera system compared to data acquired with unmanned aerial vehicle (UAV, or drone) surveys of a reflective beach. Using one year of 15-min video data and one year of monthly UAV observations, the intertidal profile shows a good agreement. Underestimations of intertidal profile elevations by the camera-based method are possibly linked to the camera view angle, rectification and gaps in data. The resolution of the video-derived intertidal topographic profiles confirmed, however, the suitability of the method in providing beach mobility surveys matching those required for a quantitative analysis of nearshore changes. Beach slopes were found to vary between 0.1 and 0.7, with a steep slope in May to July 2018 and a gentle slope in December 2018. Large but short-scale beach variations occurred between August 2018 and October 2018 and corresponded to relatively high wave events. In one year, this dynamic beach lost 7 m. At this rate, and as also observed at other beaches nearby, important coastal facilities and infrastructure will be prone to erosion. The data suggest that a low-cost shore-based camera, particularly when used in a network along the coast, can produce profile data for effective coastal management in West Africa and elsewhere.

Download Full-text

Educational Low-Cost C-Band FMCW Radar System Comprising Commercial Off-the-Shelf Components for Indoor Through-Wall Object Detection

Electronics ◽

10.3390/electronics10222758 ◽

2021 ◽

Vol 10 (22) ◽

pp. 2758

Author(s):

Hyunmin Jeong ◽

Sangkil Kim

Keyword(s):

Continuous Wave ◽

Low Cost ◽

Low Noise ◽

Radar System ◽

Indoor Environments ◽

Voltage Controlled Oscillator ◽

Band Frequency ◽

Fmcw Radar ◽

Sensing Applications ◽

Commercial Off The Shelf

This paper presents an educational low-cost C-band frequency-modulated continuous wave (FMCW) radar system for use in indoor through-wall metal detection. Indoor remote-sensing applications, such as through-wall detection and positioning, are essential for the comprehensive realization of the internet of things or super-connected societies. The proposed system comprises a two-stage radio-frequency power amplifier, a voltage-controlled oscillator, circuits for frequency modulation and system synchronization, a mixer, a 3-dB power divider, a low-noise amplifier, and two cylindrical horn antennas (Tx/Rx antennas). The antenna yields gain values in the 6.8~7.8 range when operating in the 5.83~5.94 GHz frequency band. The backscattered Tx signal is sampled at 4.5 kHz using the Arduino UNO analog-to-digital converter. Thereafter, the sampled signal is transferred to the MATLAB platform and analyzed using a customized FMCW radar algorithm. The proposed system is built using commercial off-the-shelf components, and it can detect targets within a 56.3 m radius in indoor environments. In this study, the system could successfully detect targets through a 4 cm-thick ply board with a measurement accuracy of less than 10 cm.

Download Full-text

VISIBLE-REGION PHOTOGRAPHIC REMOTE SENSING OF NEARSHORE WATERS

Coastal Engineering Proceedings ◽

10.9753/icce.v16.85 ◽

1978 ◽

Vol 1 (16) ◽

pp. 85

Author(s):

Tsuguo Sunamura ◽

Kiyoshi Horikawa

Keyword(s):

Remote Sensing ◽

Image Processing ◽

Shallow Water ◽

Water Depth ◽

Low Cost ◽

Visible Region ◽

Coastal Processes ◽

Camera System ◽

Black And White

By use of a synchronized camera system, multiband black and white photographs and conventional color photographs were taken respectively with the purposes of testing filters available for shallow-water photographic bathymetry, and of checking the availability of low-cost process imagery for the study of coastal processes. Kodak Wratten filters 29, 58, and 90 were employed for the multiband photography. A Wratten 90 filter provided the best correlation between water depth and the photographic density. The low-cost imagery, obtained in a laboratory from the color photographs by applying ordinary filters without using any expensive image processing devices, proved to be useful.

Download Full-text

A low-cost towed video camera system for underwater surveys: comparative performance with standard methodology

Environmental Monitoring and Assessment ◽

10.1007/s10661-018-7070-z ◽

2018 ◽

Vol 190 (11) ◽

Author(s):

G. A. Trobbiani ◽

A. Irigoyen ◽

L. A. Venerus ◽

P. M. Fiorda ◽

A. M. Parma

Keyword(s):

Low Cost ◽

Video Camera ◽

Comparative Performance ◽

Camera System ◽

Standard Methodology ◽

Video Camera System

Download Full-text

Transmission Electron Microscopy of oriented Co84Cr14Ta2 thin films for longitudinal magnetic recording

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100088099 ◽

1991 ◽

Vol 49 ◽

pp. 756-757

Author(s):

T. P. Nolan

Keyword(s):

Thin Film ◽

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Low Cost ◽

Low Noise ◽

Information Storage ◽

High Coercivity ◽

Magnetic Alloy ◽

Magnetic Media ◽

Transmission Electron

Thin film magnetic media are being used as low cost, high density forms of information storage. The development of this technology requires the study, at the sub-micron level, of morphological, crystallographic, and magnetic properties, throughout the depth of the deposited films. As the microstructure becomes increasingly fine, widi grain sizes approaching 100Å, the unique characterization capabilities of transmission electron microscopy (TEM) have become indispensable to the analysis of such thin film magnetic media.Films were deposited at 225°C, on two NiP plated Al substrates, one polished, and one circumferentially textured with a mean roughness of 55Å. Three layers, a 750Å chromium underlayer, a 600Å layer of magnetic alloy of composition Co84Cr14Ta2, and a 300Å amorphous carbon overcoat were then sputter deposited using a dc magnetron system at a power of 1kW, in a chamber evacuated below 10-6 torr and filled to 12μm Ar pressure. The textured medium is presently used in industry owing to its high coercivity, Hc, and relatively low noise. One important feature is that the coercivity in the circumferential read/write direction is significandy higher than that in the radial direction.

Download Full-text

3-D reconstruction and analysis of mammalian mitotic spindle structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123295 ◽

1992 ◽

Vol 50 (1) ◽

pp. 578-579

Author(s):

Kent McDonald ◽

David Mastronarde ◽

Rubai Ding ◽

Eileen O'Toole ◽

J. Richard McIntosh

Keyword(s):

Cross Sections ◽

Mitotic Spindle ◽

Experimental Studies ◽

Video Camera ◽

Three Dimensions ◽

Mitotic Spindles ◽

Black And White ◽

Reconstruction Methods ◽

Spindle Structure ◽

Tissue Culture Line

Mammalian spindles are generally large and may contain over a thousand microtubules (MTs). For this reason they are difficult to reconstruct in three dimensions and many researchers have chosen to study the smaller and simpler spindles of lower eukaryotes. Nevertheless, the mammalian spindle is used for many experimental studies and it would be useful to know its detailed structure.We have been using serial cross sections and computer reconstruction methods to analyze MT distributions in mitotic spindles of PtK cells, a mammalian tissue culture line. Images from EM negatives are digtized on a light box by a Dage MTI video camera containing a black and white Saticon tube. The signal is digitized by a Parallax 1280 graphics device in a MicroVax III computer. Microtubules are digitized at a magnification such that each is 10-12 pixels in diameter.

Download Full-text

Computer simulation study about the dependence of amorphous silicon photonic waveguides efficiency on the material quality

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020190250 ◽

2020 ◽

Vol 90 (3) ◽

pp. 30502

Author(s):

Alessandro Fantoni ◽

João Costa ◽

Paulo Lourenço ◽

Manuela Vieira

Keyword(s):

Amorphous Silicon ◽

High Throughput Screening ◽

Simulation Analysis ◽

Low Cost ◽

Deposition Process ◽

Large Area ◽

Sidewall Roughness ◽

Sensing Applications ◽

Fabrication Defects ◽

The Impact

Amorphous silicon PECVD photonic integrated devices are promising candidates for low cost sensing applications. This manuscript reports a simulation analysis about the impact on the overall efficiency caused by the lithography imperfections in the deposition process. The tolerance to the fabrication defects of a photonic sensor based on surface plasmonic resonance is analysed. The simulations are performed with FDTD and BPM algorithms. The device is a plasmonic interferometer composed by an a-Si:H waveguide covered by a thin gold layer. The sensing analysis is performed by equally splitting the input light into two arms, allowing the sensor to be calibrated by its reference arm. Two different 1 × 2 power splitter configurations are presented: a directional coupler and a multimode interference splitter. The waveguide sidewall roughness is considered as the major negative effect caused by deposition imperfections. The simulation results show that plasmonic effects can be excited in the interferometric waveguide structure, allowing a sensing device with enough sensitivity to support the functioning of a bio sensor for high throughput screening. In addition, the good tolerance to the waveguide wall roughness, points out the PECVD deposition technique as reliable method for the overall sensor system to be produced in a low-cost system. The large area deposition of photonics structures, allowed by the PECVD method, can be explored to design a multiplexed system for analysis of multiple biomarkers to further increase the tolerance to fabrication defects.

Download Full-text