Computational fluid dynamics (CFD) study was done on the propeller design of a Micro aerial vehicle (quadrotor-typed) to optimize its aerodynamic performance via Shear Stress Transport K-Omega (SSTk-w)turbulence model. The quadrotor model used was WL-V303 Seeker. The design process started with airfoils selection and followed by the evaluation of drone model in hovering and cruising conditions. To sustain a 400g payload, by Momentum Theory an ideal thrust of 5.4 N should be generated by each rotor of thequadrotor and this resulted in an induced velocity of 7.4 m/s on the propeller during hovering phase, equivalent to Reynolds number of 10403 at 75% of the propeller blade radius. There were 6 propellers investigated at this Reynolds number. Sokolov airfoil which produced the largest lift-to-drag ratio was selected for full drone installation to be compared with the original model (benchmark). The CFD results showed that the Sokolov propeller generated 0.76 N of thrust more than the benchmark propeller at 7750 rpm.Despite generating higher thrust, higher drag was also experienced by the drone installed with Sokolov propellers. This resulted in lower lift-to-drag ratio than the benchmark propellers. It was also discovered that the aerodynamic performance of the drone could be further improved by changing the rotating direction of each rotor. Without making changes on the structural design, the drone performance increased by 39.58% in terms of lift-to-drag ratio by using this method.

This paper is an attempt to integrate computer vision techniques and Micro aerial vehicle guidance to design and optimize an automated mission performed by a light Micro aerial vehicle such that automating the mission becomes reasonably more efficient than performing it manually. A system is provided for warehouse management using a Micro aerial vehicle equipped with a front camera. Computer vision algorithms make it possible for the Micro aerial vehicle to locate packages, verify the presence or absence of a specified package and list the entire warehouse inventory in a short time. An innovative method is provided to detect shelves and their packages by the camera image, which enables the system to instantly plan the shortest path for the Micro aerial vehicle while performing a shelf inventory listing. Then, following the planned path completes the mission faster than conventional guidance methods. The guidance algorithm is designed such that the efficiency of automatic operations compared to human operations is significantly increased. The system is first simulated and then implemented and the test output data is provided. The tests indicate the success of the system in securing automated operations while decreasing mission time.

There are several ways to increase the aerodynamic efficiency ratio of the wing. One of the most important ones is the use of winglet at the tip of a finite wing. In the present study, four split blended winglets with different upper winglet height mounted on RQ170 Micro-aerial vehicle half model and its effects on the drag reduction in zero angles of attack compared with wing without winglet in low Reynolds number. Also, the effect of split blended winglet in different Reynolds number and angles of attack were investigated experimentally. The tests were carried out in a wind tunnel with a low speed and turbulence. The Reynolds number based on the Mean Aerodynamic Chord is changed from 22000 to 46500, and the angle of attack is adjusted from 0◦ to 20◦ . The results are representing the drag reduction in all Reynolds number and angles of attack due to using split blended winglet. It was found that with increasing Reynolds number at zero angles of attack, the drag coefficient decreases. Also, the installation of the split blended winglet with the 3cm height of upper winglet has more reduction in total drag coefficient.

The main purpose of this paper is to model and simulate flight dynamics for a flapping wing Micro aerial vehicle dragonfly-like with two pair clap and fling mechanism and active rigid tail. This article simulates the flight dynamics of a Micro aerial vehicle dragonfly-like that can also use tail movements for longitudinal stability. Initially, using Kane's method, the equations of motion of the longitudinal mode are obtained. Then aerodynamics forces of Delfly II Micro aerial vehicle and gearbox simulation are added to the equations of motion. Also, a novel design for a flapping wing Micro aerial vehicle dragonfly-like is presented, in which tail movement is similar to the movement of insect tails in longitudinal mode. In this work, the tail movement is not used as an elevator, but the rigid tail movement is used as a control torque. The difference in brush motor rpm leads to differential thrust and pitch moment generation, similar to a quadrotor. Finally, the dynamic equations and aerodynamics and gearbox are all linearized and presented as state-space equations. Also, the response of the open-loop linearized model is compared with the nonlinear response by creating suitable initial conditions for the brush motor rpm.

Winglets are one of the tools used for reducing the effects of the tip vortex. In this research, the effects of installing split blended winglet on Micro-aerial vehicle half model in order to the reduction of wing tip vortex were investigated experimentally. The experiments were conducted in an open circuit wind tunnel at velocity 16 m/s and angle of attack 10ᵒ . The Reynolds number of the model was about 3. 8×10 4 based on Mean-Aerodynamic chord. In order to measure the mean velocity and turbulence intensity, the Hot-Wire Anemometry (HWA) has been used. Experimental results in the absence of installing winglet indicated the existence of a vortex structure behind the tip of the wing which is due to the pressure difference created on the upper and lower surfaces of the wing. Turbulence intensity has it highest value in vortex core which is also observed to decrease gradually with downstream distance. The results show that in the presence of winglet, there are two clear vortex structures which one at the winglet/wing junction and the other at the tip of the winglet.

IntroductionTodays, the application of new methods for monitoring and online management of agricultural farms is necessary to increase quality and quantity of agricultural products. Remote sensing is one of the technologies that can be used to monitor agricultural farms and natural resources. This technology is capable of detection and prediction of farm changes by application of satellite and aerial images. Satellite images have some limitations for application in agriculture, namely, high cost, low revisit time and low spatial and spectral resolutions.

Unmanned aerial vehicles (UAVs) like drones (quadcopters, hexacopters, octocopters, etc.) can be a source of significant acoustic noise. High noise makes them less suitable for use in densely populated urban areas, particularly during take-off, landing, and low-level flight, due to the noise annoyance. This paper reviews the methods and proposes some concepts for the attenuation of UAV noise. Both passive and active solutions are considered. Solutions with piston engine silencer, Q-tip propeller, more propeller blades, absorptive and reflective barrier, ducted propeller, sound absorbing ducts, synchrophaser, multichannel active noise cancellation (ANC) system with secondary sources circularly arranged around the propeller and the system with magnetically excited propeller blades are mentioneds

Objective: In order to present a new, non-destructive, accurate, and fast method for estimating the nitrogen content of corn, Unmanned aerial vehicle (UAV) multispectral sensing technology was used. Methods: The experiments were performed based on a randomized complete block design in four levels of nitrogen fertilizer (zero, 50, 100, and 150%) in Varamin in 2018. Sampling was carried out in two stages of fertilization (8-leaf Stage and Tasseling Stage). Multispectral aerial imaging and ground sampling was performed one week after each fertilizer application. After processing aerial imagery, vegetation indices were calculated and their correlation with the results of ground sampling was determined. Results: Based on the results obtained from the correlation coefficients (r) and best subsets regression, among the spectral vegetation indices, Normalized Difference Vegetation Index (NDVI), Nitrogen Reflectance Index (NIR), and Modified Triangular Vegetation Index2 (MTVI2) indices in both eight leaf collar (V8) and tasseling (VT) of maize growth stage was identified as the best indicator to estimate the nitrogen content of forage maize. At VT, a positive and significant relationship was obtained between NDVI (R2= 0.86, P≤0.001), NRI (R2= 0.70, P≤0.001) and MTVI2 (R2= 0.46, P≤0.01) indices with maize nitrogen content. Conclusion: It can be concluded that UAV multispectral imaging provides acceptable accuracy in determining the nitrogen content of maize. This technology can help farmers to determine the appropriate time of fertilization.

Quadrotor unmanned aerial vehicles (UAVs) have been highly regarded in various military, research, scientific and entertainment fields due to their vast applications. In this paper, the design control of the direct reference model for updating the control parameters in the presence of noise and disturbance has been analyzed to find the optimal and desired amount in these Micro-UAVs. Then, by choosing a Lyapunov function, the systematic stability of the system is examined and after proof of stability, an adaptive law has been extracted to update the systemic parameters. The simulations results show the controller proper function to reduce the error. Utilizing the mean square error method, a comparison was made between the results of the proposed scheme and the results contained in another references, which shows an improvement in controller performance of the proposed scheme.