scholarly journals Passive Measurement of Three Optical Beacon Coordinates Using a Simultaneous Method

Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5235
Author(s):  
Jiri Nemecek ◽  
Martin Polasek

Among other things, passive methods based on the processing of images of feature points or beacons captured by an image sensor are used to measure the relative position of objects. At least two cameras usually have to be used to obtain the required information, or the cameras are combined with other sensors working on different physical principles. This paper describes the principle of passively measuring three position coordinates of an optical beacon using a simultaneous method and presents the results of corresponding experimental tests. The beacon is represented by an artificial geometric structure, consisting of several semiconductor light sources. The sources are suitably arranged to allow, all from one camera, passive measurement of the distance, two position angles, the azimuth, and the beacon elevation. The mathematical model of this method consists of working equations containing measured coordinates, geometric parameters of the beacon, and geometric parameters of the beacon image captured by the camera. All the results of these experimental tests are presented.

Author(s):  
Jiri Nemecek ◽  
Martin Polasek

The paper deals with a problem of a passive measurement of the relative position of an optical beacon and an optical camera by a simultaneous analytical method. The beacon is composed of nine light sources which are arranged in space in a defined way. The proposed beacon layout enables the measurement of the beacon range and one position angle of the camera. This paper presents the mathematical model of the measurement method and the results, which were gathered on the basis of two experimental measurements. The first experiment was only indicative. The extreme results of the second experiment were as follows: the minimum and maximum absolute percentage errors of the beacon range were zero and 1.72%, the minimum and maximum errors of the position angle were 0.1 deg and 1.64 deg. The standard commercial cameras and lenses with different focal lengths were used.


Author(s):  
N. Goudarzi ◽  
W. D. Zhu ◽  
H. Bahari

A novel ducted turbine, referred to as a Wind Tower, for capturing wind power in either residential or commercial scale applications is studied theoretically and experimentally. A mathematical model is developed to predict the flow behavior inside the tower and a velocity coefficient is defined to correct the results at different test conditions. A wind tower prototype, including a four-quadrant-peak wind-catcher rooftop, a tower, a nozzle, and a turbine, is designed and fabricated. The captured wind power values from the mathematical model and the preliminary experimental tests are compared. While the mathematical model provides a good estimation of the output power in some cases, more precise experimental tests and simulation techniques are required to improve the mathematical model in some other cases. Significant changes in the output wind speed due to pressure differences created by the surrounding environment, the tower height, and the number of nozzles are observed. The advantages of being maintenance free, reliable, and sustainable, together with its special design that eliminates bird/bat mortality make the Wind Tower a promising solution for residential, commercial, and even off-grid applications.


2016 ◽  
Vol 823 ◽  
pp. 91-94 ◽  
Author(s):  
Adriana Ionescu ◽  
Cristian Burada ◽  
Mihai Negru

In this paper is presented a new mathematical model which is intended to simulate the hysteretic phenomenon of SERB-C Romanian friction device for damping and dissipation of earthquake energy used for buildings. These devices have unusual shape of force-displacement loop which can be simulated with our new model which represents a specific adaptation of the well known Bouc-Wen hysteretic model. The purpose of this analytical simulation is to determine a relation for the hysteretic loop which was obtained by experimental tests performed by the authors. The mathematical model presented in this paper can be used in computational simulation of a building protected with these types of devices, in order to determine the anti-seismic performances of a Romanian friction building protection system.


Author(s):  
Jiqing Chen ◽  
Shaorong Xie ◽  
Jun Luo ◽  
Hengyu Li

Purpose – The purpose of this paper was to solve the shortage of carrying energy in probing robot and make full use of wind resources in the Antarctic expedition by designing a four-wheel land-yacht. Land-yacht is a new kind of mobile robot powered by the wind using a sail. The mathematical model and trajectory of the land-yacht are presented in this paper. Design/methodology/approach – The mechanism analysis method and experimental modeling method are used to establish a dual-input and dual-output mathematical model for the motion of land-yacht. First, the land-yacht’s model structure is obtained by using mechanism analysis. Then, the models of steering gear, servomotors and force of wing sail are analyzed and validated. Finally, the motion of land-yacht is simulated according to the mathematical model. Findings – The mathematical model is used to analyze linear motion and steering motion. Compared with the simulation results and the actual experimental tests, the feasibility and reliability of the proposed land-yacht modeling are verified. It can travel according to the given signal. Practical implications – This land-yacht can be used in the Antarctic, outer planet or for harsh environment exploration. Originality/value – A land-yacht is designed, and the contribution of this research is the development of a mathematical model for land-yacht robot. It provides a theoretical basis for analysis of the land-yacht’s motion.


Drones ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 113
Author(s):  
Aleksey Kabanov ◽  
Vadim Kramar ◽  
Igor Ermakov

With the development of underwater technology, it is important to develop a wide range of autonomous and remotely operated underwater vehicles for various tasks. Depending on the problem that needs to be solved, vehicles will have different designs and dimensions, while the issues surrounding reduced costs and increasing the functionality of vehicles are relevant. This article discusses the development of inspection class experimental remotely operated vehicles (ROVs) for performing coastal underwater inspection operations, with a smaller number of thrusters, but having the same functional capabilities in terms of controllability (as vehicles with traditionally-shaped layouts). The proposed design provides controllability of the vehicle in six degrees of freedom, using six thrusters. In classical design vehicles, such controllability is usually achieved using eight thrusters. The proposed design of the ROV is described; the mathematical model, the results of modeling, and experimental tests of the developed ROVs are shown.


2020 ◽  
Vol 27 (2) ◽  
pp. 125-135 ◽  
Author(s):  
Paweł Śliwiński

AbstractIn this paper, mechanical losses in a hydraulic motor supplied with water and mineral oil (two liquids having significantly different viscosity and lubricating properties) are described and compared. The experimental tests were conducted using a special design (prototype) of a hydraulic satellite motor. The design of the satellite motor is presented. This motor was developed to supply both with water and mineral oil and features a non-circular tooth working mechanism. The paper also characterizes sources of mechanical losses in this motor. On this basis, a mathematical model of these losses has been developed and presented. The results of calculation of mechanical losses according to the model are compared with the experimental results. Experimental studies have shown that the mechanical losses in the motor supplied with water are 2.8 times greater than those in the motor supplied with oil. The work demonstrates that the mechanical losses in both the motor supplied with water and the one supplied with oil are described well by the mathematical model. It has been found that for the loaded motor working at high speed, the simulation results differ from experimental ones by no more than 3% for oil and 4% for water.


2012 ◽  
Vol 186 ◽  
pp. 58-69
Author(s):  
Ghiţă Bârsan ◽  
Silviu Mihai Petrişor ◽  
Luminiţa Giurgiu

The research of advanced gun barrels focuses on materials or the combination between advanced materials and new innovative processes that enable the increase of the life cycle and performances of all calibers cannons. In addition to the investigation of new materials, considerable efforts were made for developing new techniques. The paper describes a theoretical framework validated with the experimental tests for increasing mechanical properties of thick-walled tubes subjected to high interior pressure loads. The theoretical model established a mathematical model of calculus for non-linear environments in the case of self-hooping or autofrettaging of the thick-walled tubes. The mathematical model was validated with experimental tests performed in the Mechanical Engineering Laboratory of the Military Technical Academy in Bucharest on a standard tension test specimens collected from the abutment barrel made out of alloyed steel. Finally, the present paper introduces some theoretical guidelines of hydrostatic procedure in the field of artillery barrels manufacturing, as well as experimental data obtained after using the autofrettage procedure.


2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Zhijun Li ◽  
Yicheng Zeng ◽  
Minglin Ma

A new floating emulator for the flux-controlled memristor is introduced in this paper. The proposed emulator circuit is very simple and consists of only two current feedback operational amplifiers (CFOAs), two analog multipliers, three resistors, and two capacitors. The emulator can be configured as an incremental or decremental type memristor by using an additional switch. The mathematical model of the emulator is derived to characterize its behavior. The hysteresis behavior of the emulator is discussed in detail, showing that the pinched hysteresis loops in v-i plane depend not only on the amplitude-to-frequency ratio of the exciting signal but also on the time constant of the emulator circuit itself. Experimental tests are provided to validate the emulator’s workability.


2008 ◽  
Vol 130 (2) ◽  
Author(s):  
J. Oliveros ◽  
J. L. Alamilla ◽  
E. Astudillo ◽  
O. Flores

The mathematical model to predict failure pressures in corroded pipelines proposed in this work is based on the analysis of the original model by Cronin and Pick. New definitions and interpretations in order to obtain this new model are given. As a consequence of this, the model can be more adequately interpreted and easier to apply under practical conditions. The new model and the finite element method are applied to predict failure pressures for pipelines with corrosion defects of elliptic and irregular geometries, and the predictions are similar. The model is used to predict the failure pressure in actual defects and compared to results of experimental tests and the original model. This study shows that pressures predicted by the model presented here are comparable to those of experimental tests.


Author(s):  
Juan C. Botero ◽  
Massimiliano Gobbi ◽  
Giampiero Mastinu

In this paper a new theoretical model to estimate the transmitted force in a snow-chain safety device is presented. Starting with a detailed analysis of the significant external forces acting on the system, the mathematical model is developed using some basic concepts of the contact mechanics theory. A MATLAB® code was developed in order to perform numerical simulations and experimental tests were carried out to validate the model. The results obtained show that for certain conditions of the driving surface and the tire's tread the force transmitted along the chain can be several times the longitudinal traction force applied to the tire itself. The importance of the interaction between the blocks on the tire and the chain segments is discussed. Some conclusions and recommendations are made in order to improve the design process of this kind of devices.


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