Politeknik & Kolej Komuniti Journal of Engineering and Technology

Morphology and Optical Properties of TiO2 Thin Films Acquired by Sol–gel Spin Coating Method Using Titanium (IV) Butoxide

Nor Damsyik Mohd Said — 2025-06-30

Titanium dioxide (TiO₂) is widely recognised for its excellent electronic properties, particularly in gas-sensing applications. However, its large optical band gap limits electron transitions between the valence and conduction bands, restricting its full potential. This study investigates the fabrication of TiO₂ thin films using the sol-gel spin-coating method, with varying concentrations of titanium (IV) butoxide: 1.0 mL, 1.5 mL, and 2.0 mL. The primary objective is to optimise the concentration and analyse its impact on the films' morphological, topography and optical properties. To achieve this, the films were characterised using Field Emission Scanning Electron Microscopy (FE-SEM) and Atomic Force Microscopy (AFM) to evaluate surface morphology, cross-sectional structure, grain size, and roughness. The optimised concentration of 2.0 mL titanium (IV) butoxide produced films with a uniform coating, enhanced by solution ageing and controlled annealing temperature. FE-SEM images revealed a combination of nano-sized and micro-sized particles, with an increase in grain size correlating to pile-up at grain boundaries and an increase in roughness (3.914 nm). Additionally, UV spectroscopy analysis showed a reduced optical band gap of 3.20 eV and high transmittance. These results suggest that TiO₂ thin films, with their promising electronic and optical properties, hold significant potential for applications in gas sensors and solar cells.

Design and Development of an Intelligent Autonomous Robot for Elderly Nursing Care Applications

Siaw Wee Bong — 2025-06-30

In recent years, Malaysia has experienced a steady increase in its elderly population, with adults aged 65 and above rising from 7.2% in 2022 to 7.4% in 2023, as reported by the Department of Statistics Malaysia (DOSM). By 2024, this number of senior citizens is projected to exceed six million, leading to a growing demand for elderly care services and applications. This demographic shift poses significant challenges, particularly due to a shortage of caregiving personnel and limited availability of family members to provide full-time support. To address this issue, an Intelligent Autonomous Robot (IAR) for elderly nursing care applications was designed and developed to assist with routine care tasks and reduce dependency on human resources. In this study, the IAR is equipped to autonomously deliver food, water, and medication to elderly individuals within care facilities. The system utilises an ESP32 microcontroller with built-in Wi-Fi and Bluetooth for remote monitoring and control, supported by infrared sensors for line detection, ultrasonic sensors for obstacle and checkpoint identification, and direct current (DC) motors driven by motor drivers for navigation. Upon reaching each checkpoint, the robot halts for a predetermined duration before continuing its route and notifies nursing staff via Telegram upon successful medication delivery. Initial testing in a simulated care environment demonstrated the robot’s functionality and consistency in completing delivery cycles without human intervention. This innovation highlights the potential of autonomous robotic systems to enhance the efficiency and sustainability of elderly care applications, particularly in the context of limited manpower and increasing care demands.

Evaluating the Structural Advantages of Concrete-Filled Steel Tubes for Resilient Building Design

Siti Arinah Sanat — 2025-06-30

Concrete-filled steel tube (CFST) columns have gained increasing popularity in the construction industry due to their enhanced structural properties and versatility in various forms. CFST columns are widely used in the construction of bridges, power transmission towers, and high-rise buildings, particularly in earthquake-prone regions. Despite their advantages, additional research is needed to fully understand their behaviour under axial loads, compression and fire exposure, particularly in dynamic conditions such as seismic events. This study evaluates recent literature on the structural advantages of CFST columns, focusing on several critical design factors such as the length-to-diameter ratio, steel tube wall thickness and their performance under compressive, axial, and fire stresses. The results show that CFST columns exhibit superior strength and ductility compared to conventional materials, with key design factors, such as tube dimensions and material properties, influencing their performance. Fire performance studies indicate that CFSTs maintain structural integrity under moderate fire conditions, although more research is required for extreme scenarios. The findings have important implications for the design of seismic-resistant structures, highlighting the need for optimised CFST designs to improve safety and durability in earthquake-prone areas. Future research should focus on advanced modelling techniques and further experimental studies to refine CFST design and expand its applications in construction.

Computational Study on Buckling Capacity of Lipped Channel Beams Infilled with Concrete

Teck Jung Chai — 2025-06-30

This paper presents a computational study employing finite element analysis (FEA) to evaluate the buckling capacity of lipped channel beams infilled with concrete. Lipped channel sections with overall depths ranging from 100 mm to 250 mm, commonly available in the local construction industry, were analysed with beam lengths varying between 3.0 m and 7.5 m. Two sets of beam configurations were modelled: control beams consisted of a plain lipped channel section and another set infilled with concrete. The analysis was conducted under two types of boundary conditions: simply supported (pinned-roller) and pinned-pinned supports. Buckling analysis was performed using LUSAS FEA software, applying a four-point bending test to simulate realistic loading conditions. The results reveal that larger-lipped channel sections exhibited higher buckling capacities for both plain and concrete-infilled configurations. Additionally, concrete-infilled lipped channel beams with pinned-pinned support achieved greater capacities compared to their simply supported counterparts. However, longer span beams, being slenderer, demonstrated reduced buckling capacity. The buckling capacity of lipped channel beams increased significantly with concrete infill compared to plain-lipped channel beams. Overall, this study highlights concrete infill as an effective method to enhance the structural capacity of open steel sections, providing a viable solution for improving their buckling performance.

The Comparison of InnoSAT Attitude Control Performance with the Impact of Delay Using PID-Lead, MPC-Lead, and MPC-PDLead Controllers

Fadzilah Hashim — 2025-06-30

The development of space technology is increasingly regarded as a strategic indicator of national progress, and Malaysia is among the emerging nations actively investing in satellite research and innovation. One of the critical challenges in satellite operations is maintaining stable attitude control in the presence of orbital disturbances. This study focuses on enhancing the stability of the Malaysian Innovative Satellite (InnoSAT), a nanosatellite platform, by improving its attitude control mechanisms. InnoSAT's control performance can be affected by various real-world factors, including time delays, sensor noise, and fluctuating system gains. To replicate realistic conditions, the study incorporates delay effects into simulations of the satellite's control system. The attitude control was initially modelled using the state-space approach. Three hybrid control strategies—PID-Lead, MPC-Lead, and MPC-PDLead—were then designed and evaluated for their effectiveness in managing the Roll (ϕ), Pitch (θ), and Yaw (ψ) axes. Performance was assessed using the Mean Square Error (MSE) as the primary metric under noisy conditions. Simulation results showed that all MPC-based controllers significantly outperformed the PID-Lead controller, achieving lower MSE values across all axes. Among them, the MPC-Lead and MPC-PDLead controllers demonstrated superior noise resilience and faster convergence to steady-state conditions. These findings suggest that MPC-based approaches offer a more robust and accurate solution for InnoSAT's attitude control, particularly under the influence of real-world disturbances.

Design and Development of Photovoltaic Planning Installation Using an Unmanned Aerial Vehicle Image in Politeknik Kuching Sarawak

Kong Fah Lee — 2025-06-30

As global efforts intensify towards adopting more sustainable energy solutions, solar energy has emerged as a leading renewable resource due to its abundance, long-term viability, and increasing accessibility. Among the most widely utilised technologies for harnessing solar energy are solar photovoltaic (PV) systems, which convert sunlight directly into electrical energy. Despite their growing deployment, identifying optimal locations for PV installation remains a significant practical challenge, especially on the rooftop. Conventional methods, such as manual rooftop surveys, are often time-consuming, costly, and may pose safety risks. This issue is particularly evident at Politeknik Kuching Sarawak where such limitations have hindered effective planning and implementation of solar PV systems. To address this challenge, the present study proposes an Unmanned Aerial Vehicle (UAV)-based approach to improve the efficiency and safety of the installation planning process. UAVs, commonly known as drones, were employed to capture high-resolution aerial images of the campus buildings. These images were subsequently processed using photogrammetry software to assess the suitability of rooftop areas for PV panel installation. Compared to conventional methods, this UAV-based technique offers several advantages, including improved safety, reduced labour costs, and significantly faster data acquisition. The results demonstrated that the system effectively identified suitable rooftop areas for PV panel installation with a high degree of visual recognition accuracy. This study highlights the practical benefits of integrating UAV technology into solar PV planning and suggests its broader potential in accelerating the transition to low-carbon energy systems, particularly within educational and institutional settings.

Assessing Light Pollution from Streetlight Designs along Major Streets in Kota Kinabalu Towards Sustainable Urban Lighting

Farah Asyikin Abd Rahman — 2025-06-30

Light pollution from streetlights is becoming an increasingly serious issue, impacting ecosystems, human health, and astronomical visibility. In Kota Kinabalu, efforts to address the effects of street lighting remain limited, resulting in low public awareness of its consequences. This study examined light pollution in two major streets in Kota Kinabalu: Jalan Tun Fuad Stephens and Jalan Pasir by measuring the brightness and visible spectrum of streetlights using a digital lux meter and smartphone camera equipped with 500 lines/mm diffraction gratings. The collected data were analysed to assess how streetlight designs affect the environment, with a focus on comparing theoretical and measured lux and lumen values. The findings revealed that the installed streetlight bulbs contributed to light pollution, particularly through lux levels that exceeded standard limits by 60%, as well as the emission of potentially harmful wavelengths such as blue and violet light. These results offer valuable insights that can help shape better urban lighting designs. Additionally, the findings can assist local governments in balancing public safety, energy efficiency, and environmental protection in street lighting designs. Future studies should expand to other areas, such as Tawau and Semporna, where sea turtle populations are common. This would help protect these creatures from the adverse effects of artificial lighting on marine ecosystems. Finally, wavelength measurements in future research could be refined using a spectral light meter to enhance accuracy.

Enhancing Hygiene and Minimising Item Loss in Public Restrooms Using Smart Sensor Technology

Muhammad Izzul Fahmi Shahizan — 2025-06-30

Public restrooms play an essential role in urban infrastructure, but frequently encounter challenges related to hygiene and user behaviour, particularly the unintentional misplacement of personal belongings. Such occurrences can lead to clutter, hygiene concerns, and a reduced quality of user experience. This study presents the development and evaluation of a smart sensor-based prototype designed to detect forgotten personal belongings and alert users before they exit the facility. The system incorporates a designated storage area equipped with real-time object detection sensors and an automated notification mechanism, controlled via an Arduino microcontroller. Although the prototype currently operates locally without internet connectivity, its architecture is designed to support future integration with Internet of Things (IoT) technologies, such as Wi-Fi and GSM modules. Experimental testing conducted in a controlled environment demonstrated an alert accuracy of 85%, with user compliance at 75%, and satisfaction at 80%. These results indicate the effectiveness of the system in enhancing user awareness, reducing clutter, and improving hygiene within public restrooms. The study highlights the potential of smart sensor technologies in improving public facility management and supports future directions, including the implementation of real-time data analytics, remote monitoring, and wider deployment across multiple facilities.