Aerospace Science and Technology
Analysis and Comparison of Fuzzy PID Controller Performance in Time and Frequency domain For a Stabilized Pitch-Yaw Gimbal

Amir Moghtadaei Rad

Volume 16, Issue 1 , June 2023, Pages 1-15

https://doi.org/10.22034/jast.2023.377460.1140

Abstract
  In this article, a complete model including cross-coupling of azimuth and elevation axes, the effect of axis friction, non-perpendicularity and imbalance of axes was implemented for the platform with two degrees of freedom. Since this model includes 3 loops of current, stability and tracking from the ...  Read More

Aerospace Science and Technology
A Method for Selection of Optimum Solidity in Design of a Tandem Compressor Blade Row

Hamzeh Eshraghi

Volume 16, Issue 1 , June 2023, Pages 16-30

https://doi.org/10.22034/jast.2023.365224.1133

Abstract
  In the current article, using results of previous researches, a guideline has been developed to select a proper value for solidity of a tandem blade row in an axial flow compressor stage. Next, using this guideline, a highly loaded tandem compressor stage has been designed. To verify the selected solidity ...  Read More

Aerospace Science and Technology
Darrieus Wind Turbine; Performance Enhancement Due to the Blade Cross-Section Optimization

Jafar Jafari; Hamid Parhizkar; Sajad Ghasemlooy

Volume 16, Issue 1 , June 2023, Pages 31-47

https://doi.org/10.22034/jast.2023.365726.1134

Abstract
  This research investigates the effect of optimization of blade cross-section on the performance of the Darrieus wind turbine. The fluid flow around a Darrieus wind turbine is simulated by URANS (Unsteady Reynolds Averaged Navier Stokes) method. And blade cross-section was modeled by the Bezier curve ...  Read More

Aerospace Science and Technology
Way Point Tracking of Fixed-Wing Unmanned Aerial Vehicles Using Backstepping Controller and Fuzzy Logic

Seyedeh sepideh Madani; mohammad ali shahi ashtiyani

Volume 16, Issue 1 , June 2023, Pages 48-55

https://doi.org/10.22034/jast.2023.103296.0

Abstract
  Nowadays, operational usage of the unmanned aerial vehicles (UAVs) in various missions is on the increase considering their capabilities. Provided that there is coordination between the UAV, navigation and control system, operational capability of the UAVs increases. Since there is no pilot in UAVs, ...  Read More

Aerospace Science and Technology
Different Intelligent Methods for Coefficient Tuning of Quadrotor Feedback-linearization Controller

Mana Ghanifar; Milad Kamzan; Morteza Tayefi

Volume 16, Issue 1 , June 2023, Pages 56-65

https://doi.org/10.22034/jast.2023.355914.1123

Abstract
  This paper investigates different intelligent methods of tuning feedback-linearization control coefficients. Feedback-linearization technique is an effective method of controlling nonlinear systems. The most critical part of designing this controller is tuning the gains, especially if the plant has complex ...  Read More

Aerospace Science and Technology
Fast Terminal Sliding Mode Control for the Soft Landing of a Space Robot on an Asteroid Considering a Barycentric Gravitational Model

Mahsa Azadmanesh; Jafar Roshanian; Mostafa Hassanalian

Volume 16, Issue 1 , June 2023, Pages 66-76

https://doi.org/10.22034/jast.2023.394618.1147

Abstract
  This study aims to control a space robot's soft-landing trajectory on the asteroid EROS433 considering a weak, yet effective gravitational field. As the research innovation, the study employs a fast terminal sliding mode control (FTSMC) to manage the landing trajectory and enhance the dynamic tracking ...  Read More

Aerospace Science and Technology
Designing a Hybrid GEO-LEO Constellation Pattern for Regional Satellite Navigation in Iran

Shahrokh Zohrabzadeh Bozorgi; Abolghasem Naghash

Volume 16, Issue 1 , June 2023, Pages 77-87

https://doi.org/10.22034/jast.2022.362842.1132

Abstract
  In this paper, a few hybrid satellite constellations including combinations of LEO and GEO satellites for providing satellite navigation and positioning services for users in Iran have been designed and proposed. The performance of the constellations has been analyzed based on DOP values variations. ...  Read More

Aerospace Science and Technology
Determination of a High-speed Centrifugal Pump's Stable Performance Range by Computational Fluid Dynamics

Ali Cheraghi; Reza Ebrahimi

Volume 16, Issue 1 , June 2023, Pages 88-100

https://doi.org/10.22034/jast.2022.357423.1128

Abstract
  Feed pumps play a crucial role in the dynamics of hydraulic systems. The surge phenomenon is a common type of instability in pumps and compressors. This phenomenon is a systematic instability and is influenced by the dynamics of all components of a hydraulic system, including tank, valves, suction pipes, ...  Read More

Aerospace Science and Technology
Investigating the relative motion of two satellites corresponding to the orbital collocation strategy

Fatemeh Amozegary; Amir reza Kosari; Mahdi Fakoor

Volume 16, Issue 1 , June 2023, Pages 101-114

https://doi.org/10.22034/jast.2023.376290.1142

Abstract
  The ever increasing demand for placing satellites in the geostationary orbit has caused the revision and change of the conventional mechanism of allocating orbital slots. Therefore, collocation approaches and station keeping of several satellites with a common position have been developed to improve ...  Read More

Aerospace Science and Technology
Aviation Accident Rescue Operation Enhancement by Geo-Tagging Pilot Communication

Kamran Raissi Charmakani; Gholamreza Moradi

Volume 16, Issue 1 , June 2023, Pages 115-123

https://doi.org/10.22034/jast.2023.385518.1144

Abstract
  Knowledge of aircraft last position and trajectory is of the utmost importance for search and rescue in aviation today. In case of an accident, this information is necessary for rapid response.The existing method of reporting the whereabouts depend upon pilot reports during flight or signals from special ...  Read More

Aerospace Science and Technology
Mixed Convection and Radiation Heat Transfer in an Enclosure Filled with Unevenly Heated Plates at Different Configurations

Sahar Noori; Armin Sheidani; Djavad Kamari

Volume 16, Issue 1 , June 2023, Pages 124-145

https://doi.org/10.22034/jast.2023.357234.1127

Abstract
  In this study the effect of different configurations of three plates located in an air-filled container, which included vertical, horizontal and tilted, on coupled radiation and natural convection heat transfer has been numerically investigated. The side walls of the cavity were kept a constant temperature, ...  Read More

Aerospace Science and Technology
Improving the performance and work-absorbing capacity of the axial-flow compressor by using tandem blades.

Alireza Sekhavat Benis; Reza Aghaei Togh

Volume 16, Issue 1 , June 2023, Pages 146-158

Abstract
  The compressor blade is responsible for increasing the flow pressure. By adding a blade behind the main blade, the compressor performance can be improved by increasing the pressure ratio and reducing the weight. The tandem improves the performance and increases the compressor absorption coefficient by ...  Read More