Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://ph02.tci-thaijo.org/index.php/ET <p><strong>ENGINEERING TRANSACTIONS : A Research Publication of Mahanakorn University of Technology (Eng. Trans. MUT)</strong> is published twice a year, i.e., one issue in every half year, by Mahanakorn University of technology (MUT). It is intended to provide a forum for publication of articles in all disciplines of engineering, related technology and applied science. Examples of broad subject areas covered by the journal include electrical engineering, civil engineering, computer engineering, mechanical engineering, computer science, and information technology. The journal publishes original research papers, practical papers, reviews, case studies, technical notes and correspondence.</p> <p><strong>Journal Abbreviation</strong>: Eng. Trans. MUT</p> <p><strong>Language</strong>: English and Thai</p> <p><strong>Publication fee</strong>: free of charge</p> <p><strong>Issues per years</strong>: 2 Issues as January - June and July - December </p> <p><strong>Review Method</strong>: Double-blind review</p> Faculty of Engineering and Technology, Mahanakorn University of Technology en-US Engineering Transactions: A Research Publication of Mahanakorn University of Technology 3027-8473 <p>Copyright @2021 Engineering Transactions&nbsp;</p> <p>Faculty of Engineering and Technology</p> <p>Mahanakorn University of Technology</p> Application of Fuzzy Logic Algorithm for Steering Assist Control of Mobile Robots https://ph02.tci-thaijo.org/index.php/ET/article/view/255932 <p><em>This paper presents the application of a fuzzy logic algorithm for steering assist control of mobile robots using CoppeliaSim EDU and Python programming. CoppeliaSim EDU is a simulation software capable of modeling the operation of mobile robots. The experiment used a model of a mobile robot with a four-wheel drive system and radar sensors for measuring angles and distances to obstacles, which serve as inputs to the fuzzy logic algorithm. The fuzzy logic algorithm utilizes the TSK (Takagi-Sugeno-Kang) method. The algorithm processes these inputs to generate outputs as steering assist angles for the mobile robot, to be used in conjunction with manual control. In this experiment, the condition was that the human operator did not manually control the steering. The experimental results showed that the mobile robot was able to steer around obstacles effectively. </em></p> Chonrat Tatiyaworanun Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 65 72 Nanowatt Analog Filter Design https://ph02.tci-thaijo.org/index.php/ET/article/view/256238 <p class="EECON-Content" style="text-indent: .25in;"><span lang="X-NONE" style="font-size: 12.0pt; font-family: 'TH SarabunPSK',sans-serif;">This paper presents the design of a nanowatt-power analog filter. Important parameters such as supply voltage, power consumption, cutoff frequency, noise, dynamic range, and <a name="_Hlk177680890"></a>figure of merit are considered in the design method. These parameters indicate the advantages and disadvantages of the designed filter. The paper provides an example of a 4th-order Chebyshev low-pass filter designed for an ECG detection system based on cascading two 2nd-order sections. The proposed circuit can operate at a 0.6 V supply, and the cutoff frequency can be adjusted from 50 Hz to 300 Hz, covering the entire frequency range of ECG signals. At a 150 Hz cutoff frequency, the proposed filter consumes 0.55 nW. </span></p> Prajuab Pawarangkoon Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 73 80 Designing an Automatic tool Changer for KUKA Robot Arm Using servo motor https://ph02.tci-thaijo.org/index.php/ET/article/view/256441 <p>This article presents the design of an automatic tool changer for a KUKA robot arm using a servo motor. The servo motor acts as a connector between the end effector and the robot’s connector to switch between two types of tools: a finger gripper tool and a vacuum tool. All components are 3D printed, and the system uses air pressure and solenoid valves to control the opening and closing of the gripper. The finger gripper operates by using a cylinder to move the piston rod, which is connected to the gripper fingers, allowing it to pick up and release objects. The vacuum tool uses air pressure differences to create enough force to lift and move objects. Test results show that the automatic tools changer can switch tools as required by the user.</p> Kornika Moolpho Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 81 88 Adaptive Band Stop Filter using Switched Capacitor for ECG Measurement https://ph02.tci-thaijo.org/index.php/ET/article/view/256666 <p>This paper presents an adaptive band stop filter using a switched capacitor for eliminating electrocardiogram (ECG) noise which has an adaptive frequency band in the range of 40 - 60 Hz. The simulated interference attenuation rate is of up to -70dB and a quality factor is of up to 9. In this paper, the frequency is used to switch 100 times of the center frequency by using a band filter circuit, a frequency-to-voltage converter and a signal generator circuit controlled from voltage.&nbsp; This leads to create a clock signal for the switched capacitor circuit. In this paper, the frequency response is simulated in comparison with ECG signals in the time domain. The&nbsp; experimental results were satisfactory that can be used as a guideline to design a single-chip integrated circuits.</p> <p>&nbsp;</p> Kornika Moolpho Siripong Wongkharn Krissada Kuntawong Veerachai Mahayavej Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 89 97 Development of an Automatic Pneumatics Robotic Arm for Gripping Workpieces Controlled and Displayed via Web Server Functions https://ph02.tci-thaijo.org/index.php/ET/article/view/256494 <p>This paper presents the development of a robotic arm for gripping workpieces using an automatic pneumatic system. It can be controlled and displayed via a web server function. The design of the structure of the robotic arm has a size and proportion similar to an automatic control system in industry. The pneumatic robotic arm structure was drawn using SketchUp in 3D and the pneumatic control circuit was simulated using Automation Studio 5.0 to confirm the operation. A programmable logic controller, MELSEC IQ FX5U 32 I/O PLC, is used, which can be controlled and displayed via the web server function. The results of the designed automatic pneumatic robotic arm system were compared with the performance of the Fiber Optic Proximity Sensor, Optical Proximity Sensor, and Photo Proximity Sensor, respectively. The test results confirm the operation of the designed automatic pneumatic robotic arm system which can be applied as teaching media</p> Amnaj Prajong Phatsakorn Boonlom Thirapat Nuankasa Therdpun Chukorn Suriya Adirek Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 98 107 Hardware Requirement of Active Reconfigurable Intelligent Surface for A Single-User Single-Input Single-Output Non-Line-of-Sight 5G Communication System https://ph02.tci-thaijo.org/index.php/ET/article/view/256802 <p>A hardware specification of an active reconfigurable intelligent surface (<em>a</em>RIS), which possesses the capability to mitigate the adverse multiplicative fading effect in non-line-of-sight communication systems employing a reflective antenna, is investigated. Based on its detailed link budget analysis, the salient characteristic and operational insight of an <em>a</em>RIS are discussed. For a specific example of an <em>a</em>RIS-assisted single-user single-input single output wireless communication system operating at millimeter-wave frequencies, a requirement of the <em>a</em>RIS hardware is determined, including noise figure, gain, power and linearity, under both normal and weak path loss condi-tions. Discussion on performance trade-off is also given.</p> Apisak Worapishet Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 108 114 Application of YOLOv5 and ReLU for Weather Forecasting in Aeronautical Meteorological Services https://ph02.tci-thaijo.org/index.php/ET/article/view/257095 <p>This paper compares the use of deep learning with YOLOv5 and ReLU to create a prediction system for Aeronautical Meteorological Services. The system forecasts five types of weather conditions: BKN, CAVOK, FEW, OVER, and SCT. The evaluative information for the images is based on observing the characteristics of grouped clouds and comparing them with quantities in the sky using the "okta" unit of measurement, which divides each image into eight parts. Thus, the deep learning aspect of this paper involves teaching the model to recognize various image characteristics both during the day and at night to use the forecast results to inform sky conditions. The process described in this article involves three steps: The first step is to train the data with images that have varying characteristics from the five data types. The next step is to test the accuracy of the weights generated from the training and training steps. The final step is to use the weights to create a decision-making system for users. From the experiment, a private dataset in this article used more than 10,000 images in the testing. The experimental results found that the average accuracy results for the YOLOv5 and ReLU algorithms could be measured at 80.88% and 76.82%, respectively.</p> Nattapong Jundang Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 115 125 A Study of Thermal Comfort and Energy Saving of using Air-Conditioner Combine with Electric Fan https://ph02.tci-thaijo.org/index.php/ET/article/view/257087 <p>This research aimed to study the thermal comfort of people in an office environment when using air conditioner combined with electric fan. The temperature in the test room was adjusted from 27-30 °C, the average wind speed of the fan was 0.28 m/s, and the desk fan was 1.5 meters away from the subject. Total subjects were consisted of 50 people, 37 males and 13 females, with an average age of 30.53 years. They were in a sitting position, an activity level of 1.2 met., an average clothing value was 0.44 clo. The results showed that subjects had the highest level of satisfaction at a room temperature of 27 °C with a non-swing fan, which was 86%. The results of the experiment showed that the energy saving when adjusting the room temperature from 26-27 °C was 15.82%.</p> Nuparb Yamtraipat Sumate athitbun-anan Copyright (c) 2024 Engineering Transactions: A Research Publication of Mahanakorn University of Technology https://creativecommons.org/licenses/by-nc-nd/4.0 2024-12-25 2024-12-25 27 2 126 135