Exact laser beam positioning for measurement of vegetation vitality

2017 ◽  
Vol 44 (4) ◽  
pp. 532-541 ◽  
Author(s):  
Lars Lindner ◽  
Oleg Sergiyenko ◽  
Moises Rivas-López ◽  
Daniel Hernández-Balbuena ◽  
Wendy Flores-Fuentes ◽  
...  
Keyword(s):  
Laser Beam ◽  
Unmanned Aerial Vehicle ◽  
Laser Energy ◽  
Vision System ◽  
Field Of View ◽  
Continuous Control ◽  
High Quality ◽  
Content Type ◽  
Dc Motors ◽  
Aerial Vehicle

Purpose The purpose of this paper is to present a novel application for a newly developed Technical Vision System (TVS), which uses a laser scanner and dynamic triangulation, to determine the vitality of agriculture vegetation. This vision system, installed on an unmanned aerial vehicle, shall measure the reflected laser energy and thereby determine the normalized differenced vegetation index. Design/methodology/approach The newly developed TVS shall be installed on the front part of the unmanned aerial vehicle, to perform line-by-line scan in the vision system field-of-view. The TVS uses high-quality DC motors, instead of previously researched low-quality DC motors, to eliminate the existence of two mutually exclusive conditions, for exact positioning of a DC motor shaft. The use of high-quality DC motors reduces the positioning error after control. Findings Present paper emphasizes the exact laser beam positioning in the field-of-view of a TVS. By use of high-quality instead of low-quality DC motors, a significant reduced positioning time was achieved, maintaining the relative angular position error less than 1 per cent. Best results were achieved, by realizing a quasi-continuous control, using a high pulse-width modulated duty cycle resolution and a high execution frequency of the positioning algorithm. Originality/value The originality of present paper is represented by the novel application of the newly developed TVS in the field of agriculture. The vitality of vegetation shall be determined by measuring the reflected laser energy of a scanned agriculture zone. The paper’s main focus is on the exact laser beam positioning within the TVS field-of-view, using high-quality DC motors in closed-loop position control configuration.

Responsibly regulating the civilian unmanned aerial vehicle deployment in India and Japan

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Anjan Chamuah ◽  
Rajbeer Singh
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Regulatory Framework ◽  
Responsible Innovation ◽  
Primary Data ◽  
Snowball Sampling ◽  
Content Type ◽  
Current Scenario ◽  
Aerial Vehicle ◽  
Innovative Work ◽  
Trust Responsibility

Purpose The purpose of the paper is to describe the evolving regulatory structures of the civilian unmanned aerial vehicle (UAV) in India and Japan, not yet fully developed to regulate the deployment of the UAV. India and Japan are at the forefront to overhaul the respective regulatory framework to address issues of accountability, responsibility and risks associated with the deployment of UAV technologies. Design/methodology/approach In-depth interviews are conducted both in Japan and India to gather primary data based on the snowball sampling method. The paper addresses questions such as what is the current scenario of civilian UAV deployment in India and Japan. What are the regulation structures for Civil UAV deployment and operation and how they differ in India and Japan? What are the key regulatory challenges for Civil UAV deployment in India? How regulation structure enables or inhibits the users and operators of Civil UAVs in India? What are mutual learnings concerning UAV regulations? Findings Findings reveal that the Indian regulations address issues of responsibility by imparting values of privacy, safety, autonomy and security; Japanese regulation prefers values of trust, responsibility, safety and ownership with more freedom to experiment. Originality/value The study on civilian UAV regulatory framework is a new and innovative work embedded by the dimensions of responsibility and accountability from a responsible innovation perspective. The work is a new contribution to innovation literature looked at from regulatory structures. Field visits to both Japan and India enrich the study to a new elevation.

Vision-based pose estimation of a multi-rotor unmanned aerial vehicle

2019 ◽  
Vol 7 (3) ◽  
pp. 120-132
Author(s):  
Kashish Gupta ◽  
Bara Jamal Emran ◽  
Homayoun Najjaran
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Three Dimensional ◽  
Processing System ◽  
Training Procedure ◽  
Autonomous Landing ◽  
Content Type ◽  
Landing Platform ◽  
Aerial Vehicle ◽  
Autopilot Systems ◽  
Practical Implications

Purpose The purpose of this paper is to facilitate autonomous landing of a multi-rotor unmanned aerial vehicle (UAV) on a moving/tilting platform using a robust vision-based approach. Design/methodology/approach Autonomous landing of a multi-rotor UAV on a moving or tilting platform of unknown orientation in a GPS-denied and vision-compromised environment presents a challenge to common autopilot systems. The paper proposes a robust visual data processing system based on targets’ Oriented FAST and Rotated BRIEF features to estimate the UAV’s three-dimensional pose in real time. Findings The system is able to visually locate and identify the unique landing platform based on a cooperative marker with an error rate of 1° or less for all roll, pitch and yaw angles. Practical implications The proposed vision-based system aims at on-board use and increased reliability without a significant change to the computational load of the UAV. Originality/value The simplicity of the training procedure gives the process the flexibility needed to use a marker of any unknown/irregular shape or dimension. The process can be easily tweaked to respond to different cooperative markers. The on-board computationally inexpensive process can be added to off-the-shelf autopilots.

Design and analysis of a feedback loop to regulate the basic parameters of the unmanned aircraft

2018 ◽  
Vol 92 (3) ◽  
pp. 318-328
Author(s):  
Marcin Chodnicki ◽  
Katarzyna Bartnik ◽  
Miroslaw Nowakowski ◽  
Grzegorz Kowaleczko
Keyword(s):  
Control System ◽  
Feedback Control ◽  
Rapid Prototyping ◽  
Unmanned Aerial Vehicle ◽  
Pid Controller ◽  
Control Object ◽  
Unmanned Aircraft ◽  
Feedback Control System ◽  
Content Type ◽  
Aerial Vehicle

Purpose The motivation to perform research on feedback control system for unmanned aerial vehicles, a fact that each quadrocopter is unstable. Design/methodology/approach For this reason, it is necessary to design a control system which is capable of making unmanned aerial vehicle vertical take-off and landing (UAV VTOL) stable and controllable. For this purpose, it was decided to use a feedback control system with cascaded PID controller. The main reason for using it was that PID controllers are simple to implement and do not use much hardware resources. Moreover, cascaded control systems allow to control object response using more parameters than in a standard PID control. STM32 microcontrollers were used to make a real control system. The rapid prototyping using Embedded Coder Toolbox, FreeRTOS and STM32 CubeMX was conducted to design the algorithm of the feedback control system with cascaded PID controller for unmanned aerial vehicle vertical take-off and landings (UAV VTOLs). Findings During research, an algorithm of UAV VTOL control using the feedback control system with cascaded PID controller was designed. Tests were performed for the designed algorithm in the model simulation in Matlab/Simulink and in the real conditions. Originality/value It has been proved that an additional control loop must have a full PID controller. Moreover, a new library is presented for STM32 microcontrollers made using the Embedded Coder Toolbox just for the research. This library enabled to use rapid prototyping while developing the control algorithms.

scholarly journals Feasibility Study Using UAV Aerial Photogrammetry for a Boundary Verification Survey of a Digitalized Cadastral Area in an Urban City of Taiwan

2020 ◽  
Vol 12 (10) ◽  
pp. 1682
Author(s):  
Shih-Hong Chio ◽  
Cheng-Chu Chiang
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Focal Length ◽  
Horizontal Distance ◽  
Control Points ◽  
High Quality ◽  
Aerial Photogrammetry ◽  
Cadastral Maps ◽  
Urban City ◽  
Aerial Vehicle ◽  
Overlap Analysis

In conducting land boundary verification surveys in digitalized cadastral areas in Taiwan, possible parcel points must be surveyed. These points are employed in the overlap analysis and map registration of possible parcel points and digitalized cadastral maps to identify the coordinates of parcel points. Based on the computed horizontal distance and angle between control points and parcel points, parcels are staked out using ground surveys. Most studies survey possible parcel points using ground surveys with, for example, total stations. Compared with ground surveys, UAV (Unmanned Aerial Vehicle) aerial photogrammetry can provide more possible parcel points. Thus, an overlap analysis of digitalized cadastral maps, combined with the collection of possible parcel points, will be more comprehensive. In this study, a high-quality-medium format camera, with a 55 mm focal length, was carried on a rotary UAV to take images, with a 3 cm ground sampling distance (GSD), flying 300 m above the ground. The images were taken with an 80% end-lap and side-lap to increase the visibility of the terrain details for stereo-mapping. According to the test conducted in this study, UAV aerial photogrammetry can accurately provide supplementary control points and assist in the boundary verification of digitalized cadastral areas in Taiwan.

Model predictive control of an unmanned aerial vehicle

2017 ◽  
Vol 89 (2) ◽  
pp. 193-202 ◽  
Author(s):  
Halit Firat Erdogan ◽  
Ayhan Kural ◽  
Can Ozsoy
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Predictive Control ◽  
Control Method ◽  
Relevant Literature ◽  
Control Effort ◽  
Content Type ◽  
Multiple Input ◽  
Predictive Controller ◽  
Aerial Vehicle ◽  
Mimo Model

Purpose The purpose of this paper is to design a controller for the unmanned aerial vehicle (UAV). Design/methodology/approach In this study, the constrained multivariable multiple-input and multiple-output (MIMO) model predictive controller (MPC) has been designed to control all outputs by manipulating inputs. The aim of the autopilot of UAV is to keep the UAV around trim condition and to track airspeed commands. Findings The purpose of using this control method is to decrease the control effort under the certain constraints and deal with interactions between each output and input while tracking airspeed commands. Originality/value By using constraint, multivariable (four inputs and seven outputs) MPC unlike the relevant literature in this field, the UAV tracked airspeed commands with minimum control effort dealing with interactions between each input and output under disturbances such as wind.

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