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Based on the current widespread use of underwater vehicles, a special type of underwater glider equipped with energy-saving diamond-structured rotatable wings that can improve the underwater vehicle's lift-drag ratio optimize hydrodynamic performance, and enhance flight quality was studied. With the support of adaptive meshing technology and Fluent's epsilon standard turbulence model, lift and drag...
The collision avoidance problem of autonomous ships is analyzed in this paper. Firstly, the background and the difficulties are reviewed. Then an improved artificial potential field method is designed to solve the collision avoidance problem of unmanned ships, and the system characteristics are investigated. Finally, simulation results demonstrate the ship's control effectiveness in the obstacle environment.
In this paper we present the modeling and simulation of multi-rotors using Spatial Operator Algebra. We develop two dynamic models one where the speeds are in the inertial frame and another where the speeds are vehicle frame. In both the reference point is the center of mass, but the method applies to any point of the vehicle. Besides gravity, the external forces considered include the effect of the...
A coupled fluid-mechanical dynamics analysis method is presented in this paper. A commercial simulation package is used for mechanical dynamics calculation, which employs user-developed dynamic-link library files as routine interface to enable data exchange with gas pressure calculation. This part is responsible for the calculation of mechanical motion, including the tripping of trip trigger, releasing...
The article presents a use case evaluation of the robustness of a physical protection system for the Vodňany water tank, designated as a national critical infrastructure element. The evaluation will be performed based on three probable attack scenarios; the aim of these would be poisoning the drinking water source and intoxication of the population of the nearby city or destruction of the water tank...
Vacuum Circuit Breaker (VCB) consists of the main frame with the operating mechanism and the main circuits including VI (Vacuum Interrupter). Especially, a VCB for the generator protection, which is used in a power plant, requires very large contact spring force because it has to be able to withstand the high short circuit current. In order to release closing energy of VCB, the cam type mechanism...
When quadrupedal robots execute locomotion, their interactions with the ground surface will make themselves unstable without careful compliance control for each leg. This paper presents a control method which uses a virtual leg compliance with instantaneous reflexes to external disturbance to obtain the self-stabilization for legged robots. Each leg was modeled as two sets of virtual spring and damper...
The traditional artificial potential field method is suitable for stationary environment. In practical application, mobile robot is in a dynamic environment where the target and the obstacles are moving. For the dynamic environment, the relative position and velocity of the moving target with respect to the mobile robot and the mobile robot with respect to the moving obstacles are taken into account...
A fuzzy sliding-mode teleoperation controller for master-slave robotic systems (MSRSs) is presented in this paper. To deal with the problem of the unknown but bounded uncertainties with MSRS, the adaptive laws is designed into the control process. Moreover, the master-slave system under time delay is considered in this paper. Two simulations are given to validate the effectiveness of the provided...
This study analyzed the Balinese female dance motion from the viewpoint of a researcher in "Culture and Computing". I found that a dancer's inner power came out from inside as a movement, and that the tracking of multiple markers of Motion Capture described "Kinesphere", the sphere around the body whose periphery can easily be reached by a dancer's extended limbs without his or...
Linear flux switching motor with segmented secondary (LFSMSS) is characterized by two kinds of windings, i.e. the DC field windings and AC armature windings, which are distributed alternately on the mover. LFSMSS is vulnerable to large force ripple. This paper investigates the influence of two design techniques (dummy slot and auxiliary tooth) on the force ripple of LFSMSS. In addition, the simulation...
Active debris removal and defunct satellites mitigation is one of current hot spots in space research. Based on the deployment process, a new mixed space web is proposed in present paper. Firstly, the Vector Form Intrinsic Finite Element Method and “Kelvin-Voigt” viscoelastic constitution relation are adopted to establish the dynamic model of space web. Then the reliability of the simulation model...
Electromagnetic catapult launch tends to be equipped on future carrier deck gradually. This paper aims to establish the mathematical representation of the system of electromagnetic aircraft launch considering aspects of carrier, aircraft and electromagnetic catapult. The proposed catapult system is evaluated by conducted simulation considering disturbance of deck wind and ground effect during stroke...
The traditional metal plate bending process is difficult to meet the requirements of modern shipbuilding industry, and this paper adopts a new incremental bending process for manufacturing metal plate based on minimum energy principle and dieless forming. This process uses a set of punches and a series of highly adjustable and head rotatable supports to complete the punching process by changing the...
Cavitation nozzle is the core component of cavitation generator. It promotes cavitation by its internal special structure, producing bubble and improving the impact force of jet. The structural characteristics directly affect the quality of the cavitation jet. Therefore, the study of internal structure of nozzle is helpful to improve the performance of nozzle. Based on CFD software, taking the Helmholtz...
A novel model of heterogeneous multiple dynamic agent systems is established, which describes the chasing process between a group of agents and their quarries. In the model, the group is modeled based on inter-individual attraction and repulsion, that is, each individual can neither move away from the whole group nor get too close to other members. Moreover, two functions are introduced to reveal...
In order to improve the evacuation ability of the transfer station in Subway network operation, this research selected a complex subway transfer station, analyzed facilities and equipment of this transfer station, based on the social force model, the AnyLogic software was applied to simulate the emergency evacuation, calculated the time required for passenger evacuation in peak flow, the simulation...
In order to reduce the initial disturbance and improve the stability of air defense missile, the missile launching equations of motion are derived and simplified using the method of modal substitution. Based on these equations, the coupled rigid-flexible dynamic modeling is built in the ADAMS software to analyze the dynamic behavior and stability of missile launching process. The results indicate...
The underactuation of the standard quadrotor(four independent control input versus six output) is a serious problem which can be solved by tilting four rotors. The steering wheel is installed on each axle of the original quadrotor so that the quadrotor turns into an actuation system(eight-input versus six-output). In this paper, the dynamic model of the tilt-quadrotor is established, and the validity...
Use of a rotor type UAV that can perform three-dimensional movement and hover is being actively pursued. Although a multi-rotor type UAV is important, because it is driven by electric motors its application has the limitation of a short cruising time. In this study, the composition and control system of a single rotor UAV that achieves attitude control by pivotable vertical fins are proposed. Herein,...
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