Mohd Sani Mohamad Hashim
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Mohd Sani Mohamad Hashim
Official Name
Mohd Sani , Mohamad Hashim
Alternative Name
Hashim, Mohd Sani Mohamad
Mohamad Hashim, M. S.
Hashim, M. S.M.
Hashim, Sani
Main Affiliation
Scopus Author ID
55638811600
Researcher ID
ABA-7717-2020

Research Output

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  • Publication
    Effect of roadways plantation on signal propagation analysis in connected autonomous vehicle communication
    ( 2019)
    J S C Turner
    ;
    Shahriman Abu Bakar
    ;
    Azizi Harun
    ;
    Mohd Sani Mohamad Hashim
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Zunaidi Ibrahim
    ;
    Abu Hassan Abdullah
    ;
    M A Fadzilla
    ;
    K A A Kassim
    ;
    M S A Khalid
    ;
    Z Jawi
    ;
    M H M Isa
    ;
    S A Z Murad
    ;
    Rizalafande Che Ismail
    At present, the development of autonomous vehicle has altered the outlook of modern transportation worldwide. The state-of-the-art vehicular communication for transportation system is advancing, especially in vehicle to infrastructure (V2I) communication. An effective communication between vehicle and infrastructure has become a significant part of autonomous transportation criteria. The necessity for high quality of service communication inspire for good planning and preparation in communication process. Per se, this paper proposes vegetation attenuation models for advance planning of communication process between vehicle to infrastructure, defined mainly by plants, trees and vegetation along the roadways in Malaysia. The channel measurement performed in Universiti Malaysia Perlis test-bed having large tall trees and low shrubs along the routes resulted in several interesting results which would shape the planning of CAV communication. It is observed that communication close to low plantation or shrub requires high power consumption as the range is significantly reduced. It is also learned that certain types of plantations allows for different level of signal attenuation depending on the antenna heights. The research also found out that the attenuation profile follows strictly the log normal distribution and as such certain planning could be made to reshape the communication process to cater for this.
  • Publication
    Integration of asset tracking system through trilateration method as detection mechanism
    ( 2019)
    M A Fadzilla
    ;
    Shahriman Abu Bakar
    ;
    Azizi Harun
    ;
    Mohd Sani Mohamad Hashim
    ;
    Zuradzman Mohamad Razlan
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Z. Ibrahim
    ;
    Abu Hassan Abdullah
    ;
    J.S.C Turner
    ;
    K.A.A Kassim
    ;
    M.S.A Khalid
    ;
    Z. Jawi
    ;
    M.H.M Isa
    ;
    Rizalafande Che Ismail
    Demands for localization system has been growing rapidly in the last several years both for an outdoor and indoor area. In conjunction with this, the capability and reliability of this system to precisely locate and track objects of interest for the indoor area has catered researchers and study on how to do so. One of the major ideas on making it more advance is by incorporating the use of wireless devices into the system. There are numbers of issues that could interrupt the efficiency and success of the system. One of the main problems is the signal loss mainly caused by the attenuation of the signal as they propagate through from the transmitter to the receiver. These attenuations are mostly due to the surface types the signal are traveling on and the objects that are in the Line of Sight in between the transmitter and receiver. In order to ensure the most reliable and efficient wireless connection between transmitter and receiver, a propagation study on the signal is needed for us to analyze and find the best way to trade off the signal attenuation based on the environment surrounding the system. By doing so, a thorough system that has models that can work efficiently even if we are to consider the attenuation factors. The system consists of nodes installed inside the research institute that acts as both transmitter and receivers. The transmitter and receiver will then process the signal that will then determine their location. The receiver is connected to the laptop in order to get a real-time reading so that we will be able to locate the transmitter. A networked of nodes are installed inside the research institute for experiment and the layout of the research is conferred for future references. Data from the experiment are then analyzed and a model for the signal propagation alongside the research institute is created. This model will be able to apprehend the signal attenuation despite the surrounding environment such as furniture and walls. A completed asset tracking system with models of signal attenuation will be built in the future for a more efficient signal transmission.
  • Publication
    Signal propagation modelling for vehicle-to-infrastructure communication under the influence of metal obstruction
    ( 2021-12)
    Jamie Siregar Cynthia Turner
    ;
    Shahriman Abu Bakar
    ;
    Azizi Harun
    ;
    Mohd Sani Mohamad Hashim
    ;
    Zuradzman Mohamad Razlan
    ;
    D L Ndzi
    ;
    Rizalafande Che Ismail
    ;
    Sohiful Anuar Zainol Murad
    ;
    Mohd Nazrin Md Isa
    ;
    Shaiful Nizam Mohyar
    ;
    Mohammad Fadzli Ramli
    ;
    M K N Zulkifli
    Connected car has become one of emerging technology in the automotive industries today. This development preludes a rise in vehicular communication studies that primarily targets radio channel modelling on vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication mode. Considering vehicular obstruction, vast channel propagation studies have focused more on V2V mode while others consider the typical urban scenarios consisting of high traffic volumes of moving vehicles. Due to challenging propagation mechanisms and high complexity in such areas, radio propagation models applied in simulators assume an obstacle-free environment rather than considering the least effect imposed by metal obstruction on communication signal. Besides, there are limited studies pertaining to metal obstruction that considers several under-explored environments such as actual parking lots, junctions and other road infrastructure support. As such, this paper demonstrates signal attenuation analysis caused by the presence of metal objects in low density over obstacle-free environment on actual parking lot via V2I mode. Two scenarios such as LOS and NLOS conditions consisting of obstacle-free, cars and buses as static metal objects are evaluated. The aim of this research is to characterize signal strength caused by metal blockage on radio wave propagation predicated on the presence of vehicles as a subject of obstruction in comparison to obstacle-free vehicular environment. The validity of data is shown through received signal strength indicator (RSSI) and approximation analysis (RMSE) to demonstrate the efficiency of obtained measurements. The results demonstrated that Log-normal shadowing model yields the best fit to low-density metal obstruction scenario with smallest RMSE of 4.78 under bus obstruction whereas 5.72 under car obstruction.
  • Publication
    Analysis of WiFi Spatio-Temporal Data for Organic Fingerprinting-based Indoor Positioning System
    ( 2022-01-01)
    Abdul Halim Ismail
    ;
    Amirah Husna Mohd Hajazi
    ;
    Muhamad Safwan Muhamad Azmi
    ;
    Mohd Sani Mohamad Hashim
    ;
    Mohd Nasir Ayob
    ;
    Hassrizal Hassan Basri
    The mobile robot navigation is the next huge topic after positioning utilizing fingerprinting-based Wireless Positioning System (WPS). Many of recent works does not discuss this topic yet since many open problems in positioning topic are not yet solved, for instance the issues on multi-devices heterogeneity, instability of WiFi signals, granularity problems in grid-based indoor environment and many others. However, we anticipate that both positioning and navigation works must run in parallel so that the succession are guaranteed. This paper describes the analysis of spatio-temporal data of the signal obtained from the WiFi Access Point. Initial results suggest that the difference between transmitter heights have an effect on the spatio-temporal data while the handover of maximum signal strengths is inherent when three WiFi APs are used.
      1
  • Publication
    Numerical evaluation of aluminium 6026-T9 fracture toughness
    ( 2021-10-25)
    Zulkifli A.N.
    ;
    Muhamad Safwan Muhamad Azmi
    ;
    Ishak Ibrahim
    ;
    Mohd Sani Mohamad Hashim
    ;
    Abdul Halim Ismail
    ;
    Mohd Nasir Ayob
    Fracture is the separation of an object into two or more pieces caused by crack growth under the action of applied stress. There are many different methods for fracture evaluation has been made but still lacks information on properties of Aluminium 6026-T9. Aluminium 6026 is non-toxic since it does not contain Tin (Sn) and features a great corrosion resistance. This study focuses on the mechanical properties and fracture toughness of Aluminium 6026-T9. The material is cut and shaped into dog-bone specimens by referring the ASTM E8 and was eventually undergoing a tensile test to evaluate the mechanical properties. A linear elastic analysis of three different crack characteristics which are single edge crack, double edge crack and center crack were performed in Mode I analysis to evaluate its fracture toughness. The stress intensity factor (SIF) value near the crack tip obtained from the simulation process were then compared with analytical value and had been discussed. The percentage of error found that the numerical and analytical values are closed to each other.
      1
  • Publication
    Study on modal and harmonic response analysis by modifying motorcycle chassis using finite element method
    ( 2021-10-25)
    Wong Y.J.
    ;
    Mohd Sani Mohamad Hashim
    ;
    Shahriman Abu Bakar
    ;
    Anas Abdul Rahman
    ;
    Aziz I.A.
    ;
    Mohd Asrul Md Saad
    ;
    Nasirudin M.A.
    ;
    Zuradzman Mohamad Razlan
    ;
    Nur Saifullah Kamarrudin
    ;
    Ishak Ibrahim
    ;
    Mohd Khairul Faizi Abd Rahman
    Motorcycle chassis is one of the most important structures in the design of a motorcycle. Excessive vibration occurs in chassis is undesirable as it may lead to structural failure and discomfort among riders. This study aims to model the motorcycle chassis and carry out dynamic analysis to understand the behaviour of the chassis under vibration. Modelling of chassis was conducted based on Seri Perlis motorcycle, which is characterised by double cradle frame. In dynamic analysis, the modal and harmonic response analysis were employed in this study of the motorcycle chassis and the material used is low carbon steel. Both modal and harmonic response analysis were conducted using Ansys. The results show natural frequencies for six mode shapes and the steady-state response of the chassis under the engine weight excitation revealed that the deformation under z-axis orientation was more prevalent. From this study, the dynamic behaviour of the chassis was understood and improvement of the chassis can be made in the future.
      2
  • Publication
    Investigating Motorcycle Turn Signal Behaviors in Mixed-Traffic Environments
    ( 2021-01-01)
    Mohd Hafzi Md Isa
    ;
    Shahriman Abu Bakar
    ;
    Hamzah A.
    ;
    Ariffin A.H.
    ;
    Mohd Nazri N.N.
    ;
    Mohd Sani Mohamad Hashim
    Turn signal neglects have been identified as among the main contributors to motorcycle crashes and injuries in Malaysia. To date, several prior naturalistic observational studies have been conducted to address this situation. Nevertheless, aspects including the use of turn signals for various motorcycle movements, factors contributing to such use and how the motorcycle riders initiate and cancel the turn signals were still lacking. Thus, this study was initiated to address the aforementioned gaps through in-vehicle video recordings from the perspective of a car driver, along the pre-determined routes in several locations in Selangor and Kuala Lumpur, Malaysia. Based on the 3963 observations, the multivariate logistic regression analysis revealed that female riders and those who wore helmets, carried a pillion, ingressed and egressed the expressways, turned at the 3-legged unsignalized intersections, entered the roundabouts, performed right turns, and travelled on weekdays, at dawn, dusk, night, during inclement weather, and on single carriageway, and single lanes were significantly more likely to activate their turn signals. The results also indicated that the majority of riders initiated the turn signals before crossing the line either along expressways or at intersections. Longer duration of turn signal initiation and cancellation were observed at unsignalized intersections as compared to expressways and signalized intersections. These findings necessitate either the development of new or improvement of existing technological system to increase the use of turn signals among riders.
      1
  • Publication
    Position Tracking Performance with Fine Tune Ziegler-Nichols PID Controller for Electro-Hydraulic Actuator in Aerospace Vehicle Model
    ( 2021-12-01)
    Devendiranath K.
    ;
    Siti Marhainis Othman
    ;
    Sunar N.
    ;
    Hassrizal Hassan Basri
    ;
    Abdul Halim Ismail
    ;
    Mohd Nasir Ayob
    ;
    Azmi M.S.M.
    ;
    Mohd Sani Mohamad Hashim
    Electro-Hydraulic Actuator (EHA) system is a third order non-linear system which is highly suffer from system uncertainties such as Coulomb friction, viscous friction and pump leakage coefficient which makes this system more complicated for the designing of the controller. The Proportional-Integral-Derivative (PID) controller has proposed in this paper to control EHA system and main problem in its application is to tune the parameter to its optimum value. Two different methods are used to tune the PID controller which are trial and error and Ziegler-Nichols method. MATLAB Simulink is used to simulate the system. In order to determine the performance of EHA system for the position tracking. 3 different of external disturbance such as 0N, 5000N and 10000N has been injected into the system. Simulation results show that the Ziegler-Nichols fine tuning method provides the better tracking performance when compared to the trial and error method for every specific disturbance setting. The Ziegler Nichols method provides better disturbance rejection as the performances indexes such as percentage overshoot, settling time and steady state error are not affected by the varying of disturbance.
      1
  • Publication
    Integrating Vision System to a Pick and Place Cartesian Robot
    ( 2021-12-01)
    Tan K.S.
    ;
    Mohd Nasir Ayob
    ;
    Hassrizal Hassan Basri
    ;
    Abdul Halim Ismail
    ;
    Muhamad Safwan Muhamad Azmi
    ;
    Mohd Sani Mohamad Hashim
    ;
    Siti Marhainis Othman
    ;
    Shahriman Abu Bakar
    ;
    Low Y.H.
    Vision aided pick and place cartesian robot is a combination of machine vision system and robotic system. They communicate with each other simultaneously to perform object sorting. In this project, machine vision algorithm for object sorting to solve the problem in failure sorting due to imperfection of images edges and different types of colours is proposed. The image is acquired by a camera and followed by image calibration. Pre-processing of image is performed through these methods, which are HSI colour space transformation, Gaussian filter for image filtering, Otsu's method for image binarization, and Canny edge detection. LabVIEW edge-based geometric matching is selected for template matching. After the vision application analysed the image, electrical signal will send to robotic arm for object sorting if the acquired image is matched with template image. The proposed machine vision algorithm has yielded an accurate template matching score from 800 to 1000 under different disturbances and conditions. This machine vision algorithm provides more customizable parameters for each methods yet improves the accuracy of template matching.
      1
  • Publication
    Engine performance enhancement by improving heat transfer in between exhaust valve and valve seat through CFD (transient thermal) simulation
    ( 2021-05-03)
    Mohamad Aniq Syazwan Mohamed Hassan
    ;
    Shahriman Abu Bakar
    ;
    Zuradzman Mohamad Razlan
    ;
    Nur Saifullah Kamarrudin
    ;
    Aziz I.A.
    ;
    Wan Khairunizam Wan Ahmad
    ;
    Mohd Sani Mohamad Hashim
    ;
    Azizi Harun
    ;
    Ishak Ibrahim
    ;
    Ibrahim Z.
    ;
    Mohd Khairul Faizi Abd Rahman
    ;
    Muhammad Faiz Hilmi Rani
    ;
    Rishan Murali
    The combustion of the internal combustion engine results in high heat and pressure produce as exhaust gas. The high-temperature exhaust gas will transfer the heat to surrounding via convection, conduction, and radiation. In the combustion chamber, the exhaust valve and its seat will reach high temperatures due to hot gases exit through the engine exhaust port. This high temperature must be reduced to avoid damaging the engine. In this project, the existing material of the valve seat is tested using computational fluid dynamics simulation for heat analysis. Simulation of transient thermal is conducted to study the detailed behavior of heat transfer of the valve and valve seat in the engine. Four copper-based material of the valve seat is selected which is beryllium copper, chromium copper, brass, bronze are simulated. In the simulation, the brass valve seat has the highest heat absorbance rate which averagely 30% higher than cast iron valve seat in terms of temperature differences. Most of the copper-based valve seat can absorb averagely 10% to 30% more heat than cast iron valve seat depends on the material's thermal conductivity.
      3