A New Quasi-Steady In-Ground Effect Model for Rotorcraft Unmanned Aerial Vehicles

2019 ◽  
Author(s):  
Xiang He ◽  
Kam K. Leang
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Ground Plane ◽  
Ground Effect ◽  
P Value ◽  
Model Parameters ◽  
Blade Element Theory ◽  
Aerial Vehicles ◽  
Effect Model ◽  
3D Printed ◽  
Induced Velocity

Abstract This paper introduces a new quasi-steady in-ground effect model for rotorcraft unmanned aerial vehicles to predict the aerodynamic behavior when the vehicle’s rotors approach ground plane. The model assumes that the compression of the outflow due to the presence of ground plane induces a change in the induced velocity that can drastically affect the thrust and power output. The new empirical model describes the change in thrust as a function of the distance to an obstacle for a rotor in hover condition. Using blade element theory and the method of image, the model parameters are described in terms of the rotor pitch angle and solidity. Experiments with off-the-shelf, fixed-pitch propellers and 3D-printed variable pitch propellers are carried out to validate the model. Experimental results suggest good agreement with 9.5% root-mean-square error (RMSE) and 97% p-value of statistic significance.

scholarly journals Model-Based Autonomous Navigation with Moment of Inertia Estimation for Unmanned Aerial Vehicles

Sensors ◽  
2019 ◽  
Vol 19 (11) ◽  
pp. 2467 ◽  
Author(s):  
Hery Mwenegoha ◽  
Terry Moore ◽  
James Pinchin ◽  
Mark Jabbal
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Navigation System ◽  
Process Model ◽  
Unscented Kalman Filter ◽  
Low Cost ◽  
Moment Of Inertia ◽  
Model Parameters ◽  
Main Process ◽  
Model Based ◽  
Aerial Vehicles

The dominant navigation system for low-cost, mass-market Unmanned Aerial Vehicles (UAVs) is based on an Inertial Navigation System (INS) coupled with a Global Navigation Satellite System (GNSS). However, problems tend to arise during periods of GNSS outage where the navigation solution degrades rapidly. Therefore, this paper details a model-based integration approach for fixed wing UAVs, using the Vehicle Dynamics Model (VDM) as the main process model aided by low-cost Micro-Electro-Mechanical Systems (MEMS) inertial sensors and GNSS measurements with moment of inertia calibration using an Unscented Kalman Filter (UKF). Results show that the position error does not exceed 14.5 m in all directions after 140 s of GNSS outage. Roll and pitch errors are bounded to 0.06 degrees and the error in yaw grows slowly to 0.65 degrees after 140 s of GNSS outage. The filter is able to estimate model parameters and even the moment of inertia terms even with significant coupling between them. Pitch and yaw moment coefficient terms present significant cross coupling while roll moment terms seem to be decorrelated from all of the other terms, whilst more dynamic manoeuvres could help to improve the overall observability of the parameters.

scholarly journals Feasibility Study for Fused Deposition Modeling (FDM) 3D-Printed Propellers for Unmanned Aerial Vehicles

2020 ◽  
pp. 548-558
Author(s):  
Lorenz R. Toleos ◽  
Niño Jhim Andrew B. Dela Luna ◽  
Mark Christian E. Manuel ◽  
John Marvil R. Chua ◽  
Eldric Marius A. Sangalang ◽  
...  
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Feasibility Study ◽  
Fused Deposition Modeling ◽  
Fused Deposition ◽  
Aerial Vehicles ◽  
Deposition Modeling ◽  
3D Printed

scholarly journals Estimation of aboveground biomass using aerial photogrammetry from unmanned aerial vehicle in teak (Tectona grandis) plantation in Thailand

2020 ◽  
Vol 21 (6) ◽  
Author(s):  
SASIWIMOL RINNAMANG ◽  
KAMPANART SIRIRUEANG ◽  
SORAVIS SUPAVETCH ◽  
PONTHEP MEUNPONG
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Aboveground Biomass ◽  
Tree Height ◽  
Tectona Grandis ◽  
Aerial Images ◽  
P Value ◽  
Total Biomass ◽  
Aerial Photogrammetry ◽  
Aerial Vehicles ◽  
Ground Truthing

Abstract. Rinnamang S, Sirirueang K, Supavetch S, Meunpong P. 2020. Estimation of aboveground biomass using aerial photogrammetry from unmanned aerial vehicles in teak (Tectona grandis) plantation in Thailand. Biodiversitas 21: 2369-2376. Thailand is one of the best teak planting locations in the world. Teak is one of the most species planting and a significant source of high-value timber in Thailand. For plantation management, biomass is one of the important factors while determining the production of a plantation and also for sustainable forest management. Unmanned Aerial Vehicles (UAV) have the ability to produce 3D RGB digital images which can be used to study the plantation characteristics. This study aimed to use aerial images and photogrammetry techniques derived from unmanned aerial vehicles (UAV) to estimate teak biomass in Thong Pha Phum plantation, Kanchanaburi Province, Thailand. We conducted our study on 15-and 36-year-old teak stands, and compared the tree dimension between data obtained from field measurement and that from aerial images and photogrammetry techniques. In the 15-year-old stand, the average tree height estimated from the UAV and ground-truthing were 12.34 and 13.06 m, respectively. In the 36-year-old stand, the average tree height from the UAV and ground-truthing were 28.87 and 29.39 m, respectively. We found that in both stands, the difference between data generated from the UAV and ground-truthing data was not significant (p-value = 0.07 and 0.306, respectively). There was also a strong correspondence between tree height estimated from the UAV and that measured on the ground which is indicated by the high R2 (i.e. 0.70 and 0.64 for the 15-and 36-year-old stands, respectively). Using UAV generated data, the total biomass of 15-and 36-year-old stands was estimated to be around 42.07 t ha-1 and 67.13 t ha-1, respectively. The overall results suggest that UAV can be used as an effective tool to survey and monitor stand’s productivity in teak plantation.

A hybrid frequency-time domain technique for ground effect identification

2010 ◽  
Vol 114 (1156) ◽  
pp. 377-385
Author(s):  
A. Vitale ◽  
N. Genito ◽  
L. Garbarino ◽  
U. Ciniglio ◽  
F. Corraro
Keyword(s):  
Time Domain ◽  
Flight Control ◽  
Ground Effect ◽  
Model Parameters ◽  
Flight Data ◽  
Aerodynamic Model ◽  
Hybrid Frequency ◽  
Effect Model ◽  
Aerodynamic Derivatives ◽  
Aerodynamic Parameters

Abstract The estimation from flight data of aerodynamic parameters for vehicle in steady-state conditions, perturbed by an identification manoeuvre, is a well-established technology, whereas system identification from dynamic flight data is a subject of continuous interest. This paper presents a hybrid frequency and time domain technique for identification of vehicle longitudinal aerodynamic model, including the ground effect. Identification is performed in the framework of a multi-step approach, in which, first aerodynamic coefficients are estimated in the frequency domain, using an equation error method; then time domain techniques are applied to identify out of ground effect aerodynamic derivatives and ground effect model parameters. The technique was successfully applied to flight data of an experimental ultra light aircraft. Identification results showed that the proposed method works properly also in the dynamic phases of the flight or when no dedicated identification manoeuvres are executed. Moreover, the identified longitudinal aerodynamic model was used to design the flight control system that successfully performed many autonomous landings.

scholarly journals Quasi-Steady In-Ground-Effect Model for Single and Multirotor Aerial Vehicles

AIAA Journal ◽  
2020 ◽  
Vol 58 (12) ◽  
pp. 5318-5331
Author(s):  
Xiang He ◽  
Kam K. Leang
Keyword(s):  
Ground Effect ◽  
Aerial Vehicles ◽  
Effect Model

scholarly journals Assessment of 3D-printed span change structures applied to small unmanned aerial vehicles

2021 ◽  
Vol 13 ◽  
pp. 175682932199213
Author(s):  
Todd C Henry ◽  
John T Hrynuk ◽  
Francis R Phillips
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Structural Response ◽  
Reynolds Numbers ◽  
Aerodynamic Performance ◽  
Aerodynamic Loading ◽  
Aerial Vehicles ◽  
3D Printed ◽  
Near Term ◽  
Manufacturing Technologies ◽  
Wing Tip

An assessment of 3D-printed span-change structures is presented for determining suitability of the technology to small unmanned aerial vehicles. Materials and manufacturing technologies were used with an emphasis on near term applicability with design trades between the aerodynamic performance and structural response. Aerodynamic performance was assessed on three wind tunnel models varying span (432, 600, and 762 mm), wind speed (Reynolds numbers 18,000, 36,000, and 71,000), additive manufacturing print build plane and camber, quantifying structural response as the resulting shape during aerodynamic loading. Each model displayed increasing compliance as span increased with wing-tip displacement on the order of 50, 100, and 200 mm with various degrees of sweep and twist. Models generated excess lift at Re = 71,000 indicating potential flight demonstration of the technology with a lift to drag improvement of up to 97% at maximum wing extension.

scholarly journals Aerodynamic Performance of Propellers for Multirotor Unmanned Aerial Vehicles: Measurement, Analysis, and Experiment

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Hang Zhu ◽  
Zihao Jiang ◽  
Hang Zhao ◽  
Siyu Pei ◽  
Hongze Li ◽  
...  
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Aerodynamic Force ◽  
Experimental System ◽  
Aerodynamic Performance ◽  
Single Step ◽  
Aerial Vehicles ◽  
Measurement Analysis ◽  
Induced Velocity ◽  
Thrust And Torque ◽  
Blade Element

Analyzing the propeller aerodynamic performance is of vital importance for research and improvement of unmanned aerial vehicles. This paper presents the design requirements for a propeller for rotorcraft unmanned aerial vehicles and an analysis of a model for calculating propeller aerodynamic performance. Based on blade element momentum theory, the aerodynamic force of a blade element is analyzed and used. The symmetric airfoil NACA 0012 is used as an example to verify the validity of the model. An experimental system for propeller aerodynamic performance is designed and built to test the aerodynamic performance of six types of the propeller from a single manufacturer (APC). Data-processing software is also developed to draw curves and perform single-step calculations of three propellers’ parameters: airfoil resistance power, induced velocity, and efficiency. The results of the experiment indicate that both the thrust and torque of the propeller increase with rotational speed, propeller diameter, and propeller pitch. The research is of great significance to select more suitable propellers for unmanned aerial vehicles and the further improvement of the performance of unmanned aerial vehicles’ dynamical system.

scholarly journals Route Planning of Unmanned Aerial Vehicles under Recharging and Mission Time Constraints

2021 ◽  
Vol 6 (5) ◽  
pp. 1439-1459
Author(s):  
Kriangsak Phalapanyakoon ◽  
Peerapon Siripongwutikorn
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Large Scale ◽  
Programming Model ◽  
Route Planning ◽  
Time Constraint ◽  
Mixed Integer ◽  
Small Scale ◽  
Model Parameters ◽  
Aerial Vehicles ◽  
Mission Time

This paper investigates the problem of route planning for rechargeable unmanned aerial vehicles (UAV) under the mission time constraint in cases where more than one trip per round is required due to limited battery capacities. The goal is to determine the number of UAVs to be deployed and the flying paths that minimize the total mission cost. Unlike previous works, the electric cost incurred by UAV recharging proportional to actual flying distances is incorporated into our model. The problem is formulated as a mixed-integer programming model to minimize the sum of electric charging cost, the UAV usage cost, and the penalty cost from the violation of the mission time constraint. Extensive numerical experiments are conducted to examine the integrity and performance of the proposed model under various model parameters and deployment scenarios in grid areas and a real terrain area. The optimal solutions can be obtained for small-scale problem instances in a reasonable runtime. For large-scale problems, only feasible solutions can be obtained due to limited computational resources.

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