Scopus Research — Ameen M. Al Juboori

In this article, the modeling and model-based control of a motorcycle like inverted pendulum system with a gyroscope controller are addressed. The mathematical model of the system which includes an inverted pendulum and two gyroscopic flywheels is derived using the Lagrange equations. A problem arising from the derived dynamic model is that the system is highly nonlinear and unstable. Hence, the derived model is linearized to obtain a state-space model. Based on the linearized model, a controller and a state observer are designed. The controller is designed to generate required moment for stabilization using the two flywheel gyroscopes in the system. The observability and controllability of the designed observer and controller is verified based on the locations of the system eigenvalues. Several simulations are carried out in this work using the derived state-space model and the designed controller to ensure the efficiency of the model-based controlled system. ©2025 The authors. This article is published by IIETA and is licensed under the CC BY 4.0 license

This study investigates the airflow behaviour around vortex generators (VG) utilized in air-cooling technologies, considering the impact of rotation. The analysis encompasses a numerical approach to study the flow around vortex generators (conventional and curved delta winglet type) installed inside a duct with a heated wall. The vortex generators' set number effect on the heat transfer behaviour was investigated. Three sets of vortex generators were examined, two-VG set, four-VG set and six-VG set, equally aligned along the duct. The range of Reynolds numbers (Re) from 4000 to 12000, with the rotation number (Ro) fixed at 0.20 is covered. In this study, the thermal behaviour (measured by Nusselt Number (Nu)) and the flow behaviour (represented by) the friction factor (f)) were presented. Validation for the employed numerical model was performed based on the available experimental outcomes. The impact of using the vortex generator was evaluated and compared with the clean duct, the duct with conventional delta winglet and the curved one. The results revealed that installing the vortex generator increases the Nu (by 1.34 times at Re 4000 for four-VG and two-VG sets) and reduces the friction factor. Additionally, using the newly designed curved VG increased Nu by about 1.35. However, as the number of employed VGs enlarged, the rate of increase declined to about 0.9 of the Nusselt number value associated with the conventional VG. Furthermore, f (friction factor) reduces with the number of VG and increases with Re. In all cases, the rotation increases the Nu and f factor and using the curved VG showed a higher rate of increase. The newly designed VGs showed improved heat transfer behaviour, performing best with a four-VG set installed and worst with a six-VG set. © 2025, Semarak Ilmu Publishing. All rights reserved.

This article deals with presenting a new swing-up control approach of a double-inverted pendulum on a trolley. The dynamic model of the double-inverted pendulum is derived and linearized. Two different linearization approaches are used: first, the traditional Taylor's series approach and, second, using partial linearization. A state feedback control algorithm has been implemented based on the linearized model from Taylor's series. Furthermore, a method for swinging up the pendulum to the inversion position from rest (swing-up) has been presented. The design and implementation of the swing-up function of the pendulum are implemented using the partial linearized model. The swing-up control procedure depends on using the feedforward-feedback controllers' combination to transfer the pendulums from the downward to the upward position. The time-variant controller gain is used for the sake of the swing-up control procedure. The performances of these algorithms are shown in this paper through simulations. © 2024 Copernicus GmbH. All rights reserved.

The prolonged sitting for disabled patients can cause several health problems such as muscle wasting, bedsores, and pain. The majority of these disabled people are paraplegic patients that the activities of their muscles can effectively increase due to knee position training. In this work, a new analytical methodology for controlling the human knee position is emphasized. The knee angle profile is parameterized using seven-term exponential function. These seven coefficients are computed by fulfilling the initial and final states for knee angle, knee velocity, and electrical torque. Then, the analytical pulse width will be used to simulate the nonlinear knee dynamic system achieving the steady-state knee position with fast settling time (0.48 sec) and small overshoot (3.22%). Eventually, the introduced algorithm is confirmed in the presence of initial knee angle dispersions using Monte-Carlo simulation method. As a result, the nonlinear analytical control is successfully able to steer the human knee angle from the initial state to the desired state shortly with maximum overshoot of about 6.8% while including a wide range of initial knee angle deviations. © 2024, Cefin Publishing House. All rights reserved.

The aim of this work is the analysis of passive and semi-active damping methods on the model woven beam with a piezoelectric (PZ) layer. The mathematical model of the PZ layer on cantilever beam is derived. For modeling, real product parameters of PZ layer are used, and through simulation find the optimal values to dampen it. The resistive-inductance passive model, and State-Switch Damping SSD semi-active model are used in this work. The models are processed in the MATLAB Simulink environment and the results of the behavior of the models compared to each other. The program involving passive and semi-active systems, where analyze the behavior of the model for different parameters and the damping capabilities of individual methods are compared. The simulation results show the effectiveness of the semi-active system in comparison with the passive systems, also it shows the passive method is not so effective at low frequency as it in high frequency, and the semi-active method is not optimal for high frequency vibration. Copyright © 2024 Mustafa T. Hussein, et al.

This paper presents a method for the assessment of the geometrical properties of the turbine blade after a long running time. This method uses a medical imaging device (CT-Scan) to provide segmentation images of the turbine blade. Image processing technique was employed to produce the cross-sectional properties such as area, centroid, minimum moment of inertia, maximum moment of inertia, and the angle of twist of the principal axes along the blade span. This geometrical information was produced using MATLAB code and validated against Image-J software data. This method can be used as a nondestructive method to evaluate the geometry of the turbine. © 2023 Slovak University of Technology in Bratislava. All rights reserved.

Titanium alloys have great applications as biomaterials due to their high mechanical strength and density ratio, good corrosion resistance, and biocompatibility. Type β alloys have aroused enormous interest in the development of biomaterials due to their low elastic modulus. This new class of alloys has been formed mainly by adding tantalum, molybdenum, proven not to have biocompatibility. Tantalum is an alloy hardening element, which can increase the mechanical strength of the material. At the same time, molybdenum is a strong β-stabilizer, stabilizing the β phase with 10% quickly. In this work, Ti-15Mo-xTa system alloys were produced by the powder metallurgy method. The result shows the prepared alloy presented the β-phase grain structure, showing more excellent mechanical properties than pure titanium due to hardening in solid solution. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.

The main idea of this paper is to present the modeling and simulation of an individual 5DOF degrees of freedom robotic arm. The main axis of the modeling design will be up to the branch of science that makes up Mechatronics. The methods that have been used for the 3D model construction are presented as well as the methods for the simulation. The kinematics problem for the robot system under study is elaborated. Both forward and inverse kinematics is addressed in detail. The CAD model design is also presented. The model parameters are defined for the 3D model and the parameters are used as a base to diverge for the real system. thanks to CAD model translation to SimMechanics model, there is no need for the dynamic equations of motion derivation. The model in SimMechanics is adjusted properly for the trajectory tracking simulation. Several simulations are presented to validate the kinematics solution and the dynamics requirements for the motion. The results presented in the article shows the effectivity of the new softwares in modeling and control of engineering systems. © 2022 Institut za Istrazivanja. All rights reserved.

The demand for freshwater is in increasing with time because of global warming. The method of producing freshwater is vast. However, the use of the thermal energy of the sun is one of the promising techniques nowadays. This work proposes a new geometry of the solar still that is used to produce a distilled water out of saline water. The current paper consists of a design of the solar still in V-shape and measurement some of the main performance parameters such as the temperature of the glass cover and water, the subjected solar irradiance, and the water production under Iraqi environment conditions. The results reporting interesting points, such as a continuous rise in the temperature difference between the cover glass and the water (ΔT) with a little reduction from the peak time (14:00 hr) with ΔT =11 ºC and lowest time for solar irradiance at (18:00 hr.) with ΔT =9.0 ºC. moreover, the results showed that the actual solar irradiance that the system captures is much less than the actual amount the earth receives. The current data of this design suggests the need for a new method of efficiency calculation taking into consideration the thermal capacity of the system. © 2022 American Institute of Physics Inc.. All rights reserved.

This study explain the reason behind the low sensitivity of the natural frequency for the changes in bone health. The mechanical properties of the bone were reduced by placing the bone in boiling water for 2 hours and the mass of the bone was reduced by placing the bone in diluted acidic medium for 24 hours. The natural frequency of the bone samples (10 samples) was calculated in three cases (fresh, after boiling, and after acidic treatment). The natural frequency was calculated theoretically by using finite element analysis based upon CT-Scan DICOME images and experimentally by using impulse test. The difference between the results in the two methods was less than 15%. The boiling process caused a reduction in the natural frequency while the acidic treatment caused an increase in the natural frequency compared with the natural frequency of the fresh condition. The mutual influence of these two component cannot be separated. This mutual influence will reduce the sensitivity of the natural frequency as diagnosis factor for the changes in the health condition of the bone. © Published under licence by IOP Publishing Ltd.

This study presents the use of the transfer matrix method to calculate the natural frequencies for bovine bone. The bovine bone was considered as continues system. This continues system was transferred to discrete system by discretizing it using the Digital Imaging and Communications in Medicine (DICOM) images obtained from CT-Scan test. Those images were used to evaluate the geometrical properties of the bone segments. Geometrical properties variation along the bone length were evaluated by using image-processing technique (Binary Image). Each slice was considered as beam and the total number of beam segments is equal to the number of DICOM images. The bone was divided into 226 segments (1.25 mm slice thickness). Euler Bernoulli equation of motion was used to formulate the transfer matrix. Finite elements method based on ANSYS mechanical APDL version 14.5 was used to calculate the natural frequency. This method was used to check the discrepancy of the results obtained from the transfer matrix method. This method was done by building the three dimensional modal based upon the DICOME images and solving the modal analysis by using ANSYS software. The deviation in the results obtained from the two methods was less than 15%. The simplicity and efficiency of transfer matrix method recommends further improvement by using the gray images instead of binary images to evaluate bone geometrical, physical, and mechanical properties based upon the grayscale value of each pixel for both cortical and compact bone. © Published under licence by IOP Publishing Ltd.