Papers by Keyword: UAV

Abstract: This paper demonstrates how to establish the system level requirement set for an aviation piston engine, which is intended to be used for a MALE class UAV and for a Part 23 Normal category airplane. Here, it will be demonstrated, which requirements should be taken into account to construct the system level requirement set. This work is aimed to depict a methodology to create the system level requirement set.

Abstract: This paper presents the results of a quaternion based extend Kalman filter (EKF) and complementary filter for ArduPilotMega (APM) attitude estimation. In addition, a new method to get the measurement noise covariance matrix R is proposed. Experimental results show that the two algorithms can meet the requirements, but the complementary filter can yield better performance than EKF.

Abstract: Based on the traditional DSR Protocol has obvious drawbacks such as short network lifetime in the small reconnaissance UAV ad hoc network, a routing protocols called UEDSR(UAV Energy Dynamic Source Routing Protocol) suitable for small reconnaissance UAV ad hoc network is proposed. This protocol introduces the energy balancing mechanism into the algorithms based on DSR, then improves the situation of excessive energy consumption of hot nodes and prolongs the network lifetime. The simulation of protocol by NS2 illustrates that comparing to DSR the UEDSR protocol achieves about 7% increase in the network lifetime and the packet delivery and the average of network throughput are effectively improved.

Abstract: Aerodynamic parameter identification technology is an important method to get the aerodynamic parameter of flight vehicles. The mathematical models of flight vehicles are generally nonlinear form. In order to remove the model error caused by linearization, the output-error method has been adopted to identify the aerodynamic parameters in the longitudinal nonlinear model of an UAV (unmanned aerial vehicle) in this paper. Longitudinal nonlinear state and output equations of the UAV are established. Then simulation data of longitudinal nonlinear model with measurement noise is used to verify this method. The results show that the unknown aerodynamic parameters in the nonlinear model can be effectively identified by this method.

Abstract: UAV Video is rapidly emerging as a widely used source of imagery for many applications in recent years. This paper presents our research on the mosaic of UAV video for the purpose of harbor surveillance. First, one new framework on estimating video frame transformation with Optical flow is presented in this paper. For this new framework, fewer number of Gaussian pyramid is created for implementing for the multiresolution approach and thus, more details for optical flow computation is well kept; Second, we make a discussion on using Fourier-Mellin Transformation in image frequency domain to estimate initial motion parameter of adjacent video frames and with those initial motion parameters, small displacements for optical flow computation can be achieved; The experimental results demonstrated that the mosaic image generated from aerial video shows satisfied visual quality and its surveillance application for fast response to time-critical event, e.g., flood, is descried.

Abstract: Image stitching is an important technology to build a panorama image by combing several images with overlapped areas. In this study, we develop a image seamless mosaic and fusion technique to obtain a prefect panorama image after stitching. At first, it is using speeded-up robust features (SURF) algorithm to extract features form the images for stitching. Then, k-nearest neighbors (KNN) method is used to match the feature points and Random sample consensus (RANSAC) algorithm is used to clear them. Thirdly, a method is improved to achieve seamless stitching based on optimal suture of the overlapped areas. Experimental results indicate that this method can eliminate cohesion gap of two stitching images very well.

Abstract: This paper presents the position and attitude control of an unmanned aerial vehicle known as a quadrotor. A design methodology is introduced that a fuzzy logic controller in an intelligent way. It offers several advantages over certain types of conventional control methods, specifically in dealing with highly nonlinear systems and modeling uncertainties. The proposed controller was located at a position feedback loop which composed of x,y and z. Plus, it also designed at the angle acceleration loop. Simulation results prove the efficiency of this intelligent control strategy.

Abstract: In order to provide more flexibility in remote sensing image collection, unmanned aerial vehicle has been used to kinds of agricultural productions. Images acquired from the UAV based RS system were very useful as a result of their high spatial resolution and low turn-around time. This paper discussed general methods to process the multispectral RS data at image process level. The distortion correction caused by sensor was introduced. The geometric distortion comprised sensor distortion and external distortion caused by external parameters. At last, the general image mosaic methods were discussed.

Abstract: In recent years, monitoring long endurance UAV is widely used in civil fields such as earthquake relief, it has certain particularities in comparison with conventional UAV; this paper studied and summarized its key technologies in aerodynamic configuration. The research of aerodynamic configuration is based on a general scheme, research indicates that: (1) monitoring long endurance UAV has the characteristics of low-Reynolds number, so laminar airfoil is needed to increase lift-drag ratio; induced drag can be reduced by optimizing wing twist angle; (2) subsection control surface and new design method on flight-quality would improve control reliability and flight quality, which are indispensable for the UAV to guarantee safety in bad weather condition; (3) take-off/landing/taxiing performance should be considered in order to improve the runway adaptability of the UAV.

Abstract: According to the problem that the intelligence is not high of the soccer robot, using the mechanical theory as a guide, making some mechanical analyses and calculations on the pressure and transmutation states of chip kick mechanics, and conducting optimal design too, then making the structure of chip kick mechanics more and more rationalization. Experiments show that the new soccer robot controller features a quick response and high servo rigidity, and provide a kind of method for improving and perfecting the soccer robot control system, at the same time, filling the needs of producing.