Work place: Computer engineering department Nile University Nigeria
Research Interests: Materials Science, Models of Computation
Sadiq Thomas was born in 1980, and is a Senior Lecturer, he has several years‟ experience in academics from time spent completing his BEng in Computer Engineering and Numerical Modelling of EMATs his PhD Thesis. He has post-doctoral research and lecturing posts at various universities in the UK and Nigeria. HE completed his PhD in 2009 and his research was based on comprehensive finite element modelling of Electromagnetic Acoustic Transducer sensors used for Nondestructive testing of conductive materials particularly useful for pipeline maintenance.
DOI: https://doi.org/10.5815/ijem.2022.01.04, Pub. Date: 8 Feb. 2022
Over time, the need to extend the endurance of fixed-wing UAVs has been a challenge and requirement for the aviation industry. As a result, there are many ongoing researches on how to address this challenge while developing new concepts for an aircraft wing. This paper presents the methodology applied in the design of the wing of a lightweight unmanned aerial vehicle (UAV) that is intended for intelligence and surveillance (ISR) missions. A conceptual design was developed with the aircraft having a hybrid wing for the purpose of improving its structural design. The wing has two spars and thirteen ribs a side with an all-composite structure. Initial calculations were performed theoretically, thereafter, analyzed using the finite element analysis tool.[...] Read more.
DOI: https://doi.org/10.5815/ijem.2021.03.05, Pub. Date: 8 Jun. 2021
With the state-space method, many controllers can be designed optimally. LQR and LQG are two of these controllers. These two controllers are covered much in the literature. Despite this, not many works cover the ball-on-sphere system. Therefore, the research designed optimal LQR and LQG controllers for the system of ball-on-sphere and did a comparative analysis between the two. System dynamics were first investigated and the mathematical model was derived. After that, the system was linearized and then the state-space representation was obtained. Using this representation, the two controllers were designed and applied to the system for control. The control was done based on the specified desired system performance. Finally, the controllers' performances were analyzed and compared. Results obtained showed that both controllers met the desired system performance. With θ_x is 87.14% and θ_y is 86.43% less than their respective unregulated settling times, LQR satisfied the at least 80% performance requirement more than LQG. For LQG, θ_x is 82.35% and θ_y is 82.95% less than their respective unregulated settling times. These values are less than that of LQR. It was also observed that minimizing the total control energy leads to maximizing the total transient energy but LQG maximizes the total transient energy more than LQR. Another finding was that all states played role in regulating the controller to the desired system performance. Without regulation, LQG was found to be more efficient than LQR but in general, LQR is more efficient than LQG because, in LQG, settling time (of ball's angles) of less than 1.00 sec could not be realized. LQR is 4.79% and 3.48% more efficient than LQG in x and y directions, respectively, for the ball’s angles settling time. This research is significant because it is the first to design and do a comparative analysis of LQR and LQG controllers for the ball-on-sphere system. Therefore, bridging the existing gap in the literature is the value of this research.[...] Read more.
DOI: https://doi.org/10.5815/ijem.2020.03.05, Pub. Date: 8 Jun. 2020
Linear Quadratic Regulator (LQR) is one of the optimal control methods that continue to gain popularity. This paper designed an optimal LQR controller to control the system of the ball-on-sphere. System equations were derived and due to the nonlinearity of the system, the equations were linearized. After that, the coefficient matrices of the system dynamics were derived. Given some initial conditions, the response was simulated and controlled close to the desired values. An improvement of about 87% was achieved and the performance of the controller was observed to be good based on the simulation results. The results showed that LQR controller is one of the best optimal control methods because of its high performance improvement.[...] Read more.
DOI: https://doi.org/10.5815/ijem.2020.01.05, Pub. Date: 8 Feb. 2020
With the explosive increase in the data traffic of wireless communication systems and the scarcity of spectrum, terahertz (THz) frequency band is predicted as a hopeful contender to shore up ultra- broadband for the forthcoming beyond fifth generation (5G) communication system. THz frequency band is a bridge between millimeter wave (mmWave) and optical frequency bands. The contribution of this paper is to carry out an in-depth study of the THz channel impairments using mathematical models to evaluate the requirements for designing indoor THz communication systems at 300GHz. Atmospheric absorption loss, diffraction loss and free space path loss were investigated and modeled. Finally, we discuss several potential application scenarios of THz and the essential technical challenges that will be encountered in the future THz communications. Finally, the article finds that propagating in the THz spectrum is strongly dependent on antenna gain.[...] Read more.
DOI: https://doi.org/10.5815/ijem.2019.04.05, Pub. Date: 8 Jul. 2019
This paper introduces a wearable eyeglass with an ultrasonic sensor to help the blind to navigate alone safely, while avoiding obstacles that may be encountered, fixed or mobile, thereby preventing any possible accident. The main component of this work is the ultrasonic sensor, which is used to measure the distance to an object using sound waves. By recording the elapsed time between the wave being generated and the wave bouncing back, it is possible to calculate the distance between the sensor and the object. A limitation of the project is that even though it can operate alone as an independent device, its full functionality to be achieved, it needs to be part of a whole system hence making it an auxiliary device. An integration of this device with a smart walking stick or an automatic wheelchair can help realize its full potential and make it the ultimate mobility aid.
This system is cheap, fast and easy to use and it is an innovation for the blind and visually impaired people to help them overcome the various problems in their daily life.
DOI: https://doi.org/10.5815/ijem.2019.02.02, Pub. Date: 8 Mar. 2019
This project is aimed at developing a prototype wireless charging system that allows for charging convenience using wireless charging also called inductive charging. This allows charging to be made easier and free from connecting leads between charger and handset.
In order to successfully achieve this task, the design of the prototype was developed in two parts, a transmitter with resonator and a receiver with resonator. The transmitter converts DC voltage to AC, and transfers energy wirelessly through an LC resonator to the receiver through mutual induction, and hence induces EMF in the receiver. The EMF is rectified, filtered and regulated and output is used to charge mobile phones.
Testing results and measurements taken on this prototype shows that significant amount of EMF can be induced at receiver through air coupled transformers due to EM waves at high frequencies. The charging distance is 3cm maximum with end-to-end coupling.
Subscribe to receive issue release notifications and newsletters from MECS Press journals