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The work is intended to create and analyze mathematical model, to compare it with created information model. Matlab and Simulink is used for mathematical and information model creation correspondingly.
Inspired by flying squirrels, we put forward a novel air posture adjustment manner, the wave gliding gait (WGG) model based on flexible menmbrance deformation driven by the high frequency and low amplitude locomotion of limbs. Firstly, we extract the WGG model according to the analysis of the flying squirrel's gliding posture adjustment characteristics. Then, the concept prototype of the WGG model...
We consider the problem of making accession and promotion decisions in the United States Air Force officer sustainment system. Accession decisions determine how many officers should be hired into the system at the lowest grade for each career specialty. Promotion decisions determine how many officers should be promoted to the next highest grade. We formulate a Markov decision process model to examine...
Headquarters Air Force Studies, Analyses, and Assessments (AF/A9) supports Force Structure decisions by integrating analysis at various levels of resolution. The Combat Forces Assessment Model (CFAM), is a mixed integer program incorporating results from higher-resolution models to identify an optimal force mix within Air Force resources. CFAM is a deterministic model, but some input models are stochastic,...
Low back pain of workers is increased in workplaces that involve hard work. It is caused by excessive loading of the waist joint and muscle fatigue. Therefore, power-assist suits have been developed to decrease the load on the waist joint. However, previous power-assist suits have had problems such as low output or heaviness. Thus, we have developed an assist suit that is lightweight and exerts a...
Traditional autopilots suffer from inherent flight path control objective conflict problems, as arbitrary flight path and speed targets cannot be maintained with saturated energy rate control. Elementary flight envelope protections are typically introduced to protect airspeed and prevent loss of control, but rather as a "last line of defense", than as a mean of smooth and deterministic control...
Autonomous flight of miniature UAVs demands high performance actuators satisfying the requirements of modern control algorithms. Specially for quadrotors, where lift and control forces are the result of a synchronized action of the four BLDC/propeller actuators, the form of their propellers are fundamental to attain a fast and reliable dynamic response. In this paper, we present a mathematical model...
We have been studying an air-jet manipulation technique for controlling the position and posture of a single solid object on a plane surface by manipulating the air flow and angles of multiple air jets. This technique has a highly nonlinear nature caused by the diffusivity of air jets, so that accurate plant modeling is very difficult. Therefore, when the model greatly differs from reality, a problem...
Micro Aerial Vehicles (MAVs) are limited in their operation outdoors near obstacles by their ability to withstand wind gusts. Currently widespread position control methods such as Proportional Integral Derivative control do not perform well under the influence of gusts. Incremental Nonlinear Dynamic Inversion (INDI) is a sensor-based control technique that can control nonlinear systems subject to...
In recent years, several researchers focused their work on the mechanisms to protect the UAV from the dangerous collision with obstacles particularly the application of a spherical shell. However, this mechanism has some drawbacks when used in real-world mission especially in an outdoor environment. In the presence of wind, the spherical shell will experience significant air drag that will affect...
Change from a resting state to a full launch on any device that has the characteristic of flight and vertical landing is a major challenge when the control system must be designed. In this sense, there are different effects that alter its dynamics. In this paper, an experimental method based on pseudo-random bit signals (PRBS) is proposed to identify the transfer function of a vertical take-off and...
Reed valve is widely used in compressors. It is one of the most important compressor components. Its performance affects the compressor's efficiency. The creation of a mathematical model considering both the thermodynamic process and valve movement of the compressor involves two important coefficients: flow coefficient and effective action area coefficient. So far, no mathematical method has yet been...
This paper proposes a method to calculate the lift force of propeller using simulation software FLUENT. And on the basis of this, a certain degree of applicability of the formula from blade element theory is verified. It also presents suggestions for the analysis of the lift force of the propeller in the case of the impact of the incoming flow.
This work extends the drag-force enhanced quadrotor model by denoting the free stream air velocity as the difference between the ground speed and the wind speed. It is demonstrated that a relatively simple nonlinear observer is capable of estimating the local wind components, provided accelerometer and GPS-velocity measurements are available. We perform a wind tunnel experiment at various wind speeds...
China's first self-developed aircraft C919 has been assembly offline. Lacking in the ability to analyze the environmental stress of aviation pipeline will result in less reliability and higher failure rate of aircraft hydraulic system under variable environment conditions. Therefore we have selected a straight pipeline and a bend one of the wing position, and whose environmental stress were analyzed...
Pressure servo valve is usually used to regulate the pressure of the braking actuator to stop the wheel in traditional aircraft anti-skid braking system. The disadvantages of pressure servo valve include complex structure, high production costs, and the requirement for high quality of the hydraulic oil. In addition, its pilot stage is easy to block by contamination and has a constant leakage. This...
In this paper, a new method based on ultrasonic waves is presented for particle positioning. In this method which is called acoustophoretic, at first, the particle is levitated and then is transferred to the desired position. Finite element software was applied for investigating and analyzing the effective parameters on this process. According to the simulations, after generating standing waves in...
This paper considers trajectory tracking of a stratospheric autonomous airship. A new control scheme was proposed based on the computed torque method, a fuzzy approximation system and a compensating controller. Firstly, a dynamic model for the airship was established and the issue of trajectory control was defined. Secondly, a fuzzy adaptive trajectory control system was designed using the computational...
In the present study, computational fluid dynamics (CFD) investigation of dust particle collection efficiency in a force feed venturi scrubber has been performed using ANSYS CFX. A Venturi scrubber provides an effective way to remove dust particles flowing in a contaminated gas which are captured in fine droplets formed due to disintegration of a liquid as a result of high kinetic energy of air. Eulerian-Lagrangian...
Modelling of pneumatic muscle actuators “PMA” is one of the valued challenges in soft robotic researches, which is still under modification for the McKibben artificial muscle. Accurate force, length and position models allow for the wide use of make the continuum robot arm in industrial and medical applications. Moreover, accurate control can be achieved. This paper presents new formulas to model...
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