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The simple mechanical structure makes traditional quadrotor widely used. However, some mechanical properties that hinders its further development, such as under-actuation and limited speed when moving horizontally. Taking these issues into account, a novel quadrotor is presented in this paper while its propellers are allowed to tilt about their axes. As a result, the drawback of the under-actuation...
In this paper, a dynamic model of six degrees of freedom microcopter equipped with a robotic arm has been formulated using Newton-Euler's method. This microcopter configuration wasn't covered in scientific papers before. The resulting model is a nonlinear, coupled, and underactuated dynamic model, which includes aerodynamic effects and disturbances because of equipping the microcopter with a robotic...
The aim of this study is to design a descent control system for a CanSat that simulates a sensor payload travelling through a Martian atmosphere and sampling the atmospheric composition during flight. CanSat is a first step in space studies that gives low cost opportunity to test the space program design. The system is developed under the rules of International CanSat Competition 2016, which aims...
Feasibility study on implementing wind energy harvesting system on moving train is discussed in this study. Wind turbines installation over the train roof is suggested and tested from different aspects. Practical aspects of wind energy utilization are discussed and challenges are highlighted. Calculations of wind power generation for wagon roof mounted turbine are provided and air drag of turbine...
A sensitivity analysis is presented on the influence of the weight, altitude and speed of battery-powered sUAS on the resulting stall speed, endurance and range. To aid in the determination of the aircraft performance prior to flight, a method is being brought forth that quantifies the impact of these mission parameters. As a case study the P31015 sUAS is used. The P31015 is a concept model of a battery-powered...
Those employing Evolutionary Algorithms (EA) are constantly challenged to engineer candidate solution representations that balance expressive power (I.E. can a wide variety of potentially useful solutions be represented?) and meta-heuristic search support (I.E. does the representation support fast acquisition and subsequent fine-tuning of adequate solution candidates). In previous work with a simulated...
This work addresses an efficient and highly reliable Noise-Vibration-Harshness simulation and analysis framework for electrical induction drives in E-mobility applications. Based on a combined nonlinear analytic and Finite-Element modeling structure in spatial frequency space the entire operational Noise-Vibration-Harshness-simulation is embedded in one simulation environment and can be performed...
Stiction in control valve is one of the long-standing and common problems in the process industries, which accelerates equipment wear and even affects the stability of closed-loop systems. A valve stiction model is proposed to describe the dynamic feature of sticky valve. To detect and quantify valve stiction, a bootstrap Hammerstein system identification procedure is proposed. Through the identified...
Although air-jet looms run faster than mechanical weft insertion looms such as rapier or shuttle looms, but their production cost can be higher when their air usage is not optimized. The amount of air required for weft insertion varies greatly for each yarn type and also depends on several key factors. One of these factors is the yarn's air friendliness, which is the measure of how easy it is to project...
In recent years, military and civil aviation have put forward higher and higher requirements to the performance of the aircraft. The morphing aircraft can adapt to a variety of environments, perform a variety of tasks and meanwhile maintain excellent flight performance. This paper researches the dynamic modeling method, aerodynamic parameter analysis and the dynamic characteristic response of morphing...
In this paper, a path following control method related to the planar motion for an under-actuated autonomous airship is presented. First, the dynamic and kinematic model of the airship is introduced. Planar path-following error equations are proposed based on the virtual guidance law. Then, a nonlinear disturbance observer (NDO) is designed to estimate the constant wind force. A back-stepping method...
The concept of utilizing the Coandia effect to produce stable flight in saucer type Aerial Vehicles (AV) was first conceived in 1935 by Henri Marie Coanda. Coanda's proposed AV design remained a relatively unexplored curiosity for decades until the recent surge in popularity of small Unmanned Aerial Vehicles (UAV) revitalized interest in the topic. Coandä effect UAV offer some distinct advantages...
We present a global controller for tracking nominal trajectories with a flying wing tailsitter vehicle. The control strategy is based on a first-principles model of the vehicle dynamics that captures all relevant aerodynamic effects, and we apply an onboard parameter learning scheme in order to estimate unknown aerodynamic parameters. A cascaded control architecture is used: Based on position and...
Minimizing tip-sample interaction force is crucial for the performance of atomic force microscopes when imaging delicate samples. Conventional methods based on jumping mode such as peak force tapping require a prescribed maximum interaction force to detect tip-sample contact. However, due to the presence of drag forces (in aqueous environments), noises and cantilever dynamics, the minimal detectable...
This paper proposes an energy-saving adaptive cruise control (ACC) which exploits the future trajectory of the preceding vehicle to minimize unnecessary braking. By suitable design of the model predictive control terminal set, the proposed eco-ACC avoids unnecessary braking and improves fuel economy, while guaranteeing safety and limited online computational burden. Simulations and experiments show...
The paper investigates the influence of the ground on the airfoil lift. The Numerical Analytic Method (NAM) and the Discrete Vortices Method (DVM) are developed for simulating the flow around an airfoil when it is in the close proximity to the ground. The author proposes the NAM for modeling the flow around the airfoil near the ground and analyzes two approaches to solving the problem of Wing-in-...
This paper presents the Computational Fluid Dynamic (CFD) analysis to study the effect geometry and flow parameters on thrust force created by the flow from convergent-divergent nozzles to a suddenly expanded circular duct of larger cross-sectional area. The study is focusing on resultant thrust force. The nozzles are designed for Mach numbers 1.1, 1.4, 1.8 and 2.0. The CFD analysis is done by varying...
As the development of precise machining, electrical machines with high precision and high dynamic are the focus of research. This paper proposes three kinds of two-degree-of-freedom Voice Coil Motor (VCM), which provide linear-rotary motion. The VCM with two motion units has a great controllability and perfect rotary torque features, the one with parallel axes of motions has the highest average linear...
This paper presents the modeling of Transversal Artificial Muscles. The innovative construction enables transversal deformation of the muscle, what allows obtaining a linear displacement by changing a diameter of a muscle without changing its length. The model simulates the motion of a PAM caused by a force which depended on pressure and deformation. Theoretically predicted capacities, like generated...
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