Article Per Year (5 Year)
p-Index From 2021 - 2026
4.53
P-Index
This Author published in this journals
All Journal Mechatronics, Electrical Power, and Vehicular Technology Department of Naval Architecture Rekayasa Mesin Jurnal Rekayasa Mesin SELAPARANG: Jurnal Pengabdian Masyarakat Berkemajuan Angkasa: Jurnal Ilmiah Bidang Teknologi KACANEGARA Jurnal Pengabdian pada Masyarakat Janaka : Jurnal Pengabdian Masyarakat Jurnal Pendidikan dan Teknologi Indonesia Jurnal Ilmiah Wahana Pendidikan Society: Jurnal Pengabdian Masyarakat Jurnal Vokasi Mekanika Jurnal Rekayasa elektrika Advance Sustainable Science, Engineering and Technology (ASSET) Jurnal Abdimas Taawun: Jurnal Pengabdian kepada Masyarakat Rekayasa: Jurnal Penerapan Teknologi dan Pembelajaran Jurnal Panjar : Pengabdian Bidang Pembelajaran
Aldias Bahatmaka
Universitas Negeri Semarang
Religion Agriculture, Biological Sciences & Forestry Humanities Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Health Professions Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Law, Crime, Criminology & Criminal Justice Mechanical Engineering Medicine & Pharmacology Nursing Public Health Social Sciences Other

Published : 31 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 31 Documents
Search

 1   2   3   4 
Analyzing the Total Resistance and Wave Pattern of Purse Seine Vessels with Photovoltaic-Powered Naryanto, Rizqi Fitri; Bahatmaka, Aldias; Wibowo, Muhammad Yusuf; Ghyferi, Andi Abdullah; Fahmi, Fiqri Fadillah; Hyoung Cho, Joung
Rekayasa Vol. 22 No. 2 (2024)
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/rekayasa.v22i2.10634

Abstract

With 64.97% of its territory consisting of sea, Indonesia is one of the world's largest maritime nations and produces approximately 8.02 million tons of fish annually. Traditional fishing vessels play a crucial role in supporting livelihoods, yet their design is often based on hereditary methods rather than hydrodynamic optimization. This study uses catamaran hull forms as a design reference to analyze the total resistance and wave patterns of purse seine vessels with photovoltaic-powered systems. Computational methods are employed to predict vessel performance efficiently. The resistance analysis applies the Slender Body approach and Savitsky's mathematical model, supported by comparative studies for validation. Particular attention is given to the influence of chine configurations on resistance characteristics and wave formation. Results indicate that the addition of chines increases the Froude number and contributes to reducing total resistance. Among the variations, single chine geometry demonstrates the lowest resistance, making it the most efficient configuration for catamaran fishing vessels. While chine modifications affect the wave pattern, the hull maintains a relatively clean wake distribution. These findings highlight the potential for improving vessel design through careful chine geometry optimization combined with computational modeling. The study underscores the importance of modern hydrodynamic analysis in advancing traditional fishing vessels toward higher efficiency and sustainability. Future research is recommended to incorporate more advanced computational approaches, such as Computational Fluid Dynamics (CFD), examine water-hull interactions and enhance vessel performance under operational conditions.
Karakteristik Variasi Lateral Tilt Angle pada Friction Stir Welding Material High Density Polyethylene Terhadap Kekuatan Tarik dan Bending Azara, Salsa Bila; Ramadhani, Risky; Budi Darsono, Febri Budi; Bahatmaka, Aldias; Kriswanto, Kriswanto; Firmansyah, Hendrix Noviyanto
Angkasa: Jurnal Ilmiah Bidang Teknologi Vol 17, No 2 (2025): November
Publisher : Institut Teknologi Dirgantara Adisutjipto

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.28989/angkasa.v17i2.3004

Abstract

Friction Stir Welding (FSW) is a solid-state joining method suitable for thermoplastics like HDPE, which has lighter and more flexible properties. This study aims to examine the tensile and bending strength of HDPE joints influenced by parameters such as TRS 930 rpm, a feed rate of 20mm/min, and variations in the Lateral Tilt Angle (LTA) of 0°, 0,5°, 1°, and 1,5°, where the tool's position is sideways relative to the tool's movement direction as the main variable. Resulting in maximum tensile strength (UTS) values of 3,15 MPa, 16,0 MPa, 16,9 MPa, and 8,59 MPa. LTA 1° produced the highest UTS, while LTA 0° produced the lowest UTS because the heat input was not sufficient to perfectly bond the welding material. The bending strength values produced were 4,25 MPa, 14,3 MPa, 4,17 MPa, and 28,8 MPa. The highest stress is found at a 1,5° variation and the lowest at a 1° variation, due to uneven heat distribution during the FSW process. Therefore, choosing the right TLA during the FSW process is key to achieving HDPE joints with good mechanical strength.
Efek Sandblasting Terhadap Karakterisasi Pelapisan Coating 95MXC Pada Stainless Steel 304 Menggunakan Metode TWAS (Twin Wire Arc Spray) Puspitasari, Windy Desti; Fitriyana, Deni Fajar; Anis, Samsudin; Bahatmaka, Aldias; Irawan, Agustinus Purna; Siregar, Januar Parlaungan; Cionita, Tezara; Manalu, Janviter
Jurnal Rekayasa Mesin Vol. 19 No. 1 (2024): Volume 19, Nomor 1, April 2024
Publisher : Mechanical Engineering Department - Semarang State Polytechnic

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32497/jrm.v19i1.5392

Abstract

Impeller adalah komponen utama pompa sentrifugal yang sering mengalami kegagalan seperti erosi, korosi dan kavitasi. Untuk mencegah kegagalan tersebut, salah satu cara yang digunakan adalah memberikan pelapis dengan metode TWAS. Pada penelitian yang telah ada, coating dengan metode TWAS menjadi salah satu pilihan yang banyak digunakan, namun belum banyak penelitian yang membahas mengenai pengaruh pengulangan sandblasting pada coating metode TWAS. Penelitian ini bertujuan untuk mengetahui pengaruh pengulangan sandblasting pada impeller pompa berbahan baku stainless steel 304 dengan metode Twin Wire Arc Spray Coating dengan NiAl sebagai bond coat dan FeCrBSiMn sebagai top coat. Penelitian ini menggunakan spesimen tanpa diberikan pelapisan dan spesimen tebaik yakni yang diberi pelapisan dengan satu pengulangan sandblasting. Karakterisasi dilakukan untuk mengetahui kekasaran permukaan (ISO 8503), kekerasan lapisan (ASTM E384), coating (ASTM D4541), dan laju korosi (ASTM G102). Pengujian SEM dan analisis ImageJ dilakukan untuk mengetahui struktur lapisan. Hasil penelitian menunjukan sandblasting dengan satu pengulangan memiliki hasil kekasaran permukaan dan ketebalan lapisan terendah. Namun, memiliki hasil karakterisasi lapisan paling optimal dengan porositas dan unmelt terendah, kekerasan tertinggi dengan 1081.6 HV dengan coating yang sudah sesuai dengan standar yakni 14.5 MPa dan semakin banyak pengulangan sandblasting, semakin tinggi laju korosinya. Kesimpulan dari penelitian ini adalah satu pengulangan sandblasting dalam metode TWAS sudah memberikan kualitas terbaik yang dapat meningkatkan performa dan penggunaan impeller pompa.
Optimization Design of NACA 4412 Airfoil Based on Genetic Algorithm for Efficiency and Maximum Lift Force Laksono, Aryo Eko; Bahatmaka, Aldias; Fitriyana, Deni Fajar; Laksono, Galih Tri; Habibullah, Muhammad; Nubli, Haris; Hyung, Cho Joung
Jurnal Rekayasa Mesin Vol. 20 No. 2 (2025): Volume 20, Nomor 2, Agustus 2025
Publisher : Mechanical Engineering Department - Semarang State Polytechnic

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32497/jrm.v20i2.6531

Abstract

The NACA 4412 airfoil, renowned for its exceptional subsonic aerodynamic performance, faces critical operational constraints including elevated drag characteristics and premature stall onset at high angles of attack. While previous investigations have independently examined internal slot modifications and gurney flap implementations for aerodynamic enhancement, the synergistic potential of their combined application to the NACA 4412 configuration remains largely unexplored. This research presents a comprehensive optimization study that strategically integrates internal slot geometry with gurney flap configuration to maximize lift coefficient (CL) and aerodynamic efficiency (CL/CD) through advanced genetic algorithm optimization. The methodology employed high-fidelity computational fluid dynamics simulations using FLUENT with Spalart-Allmaras turbulence modeling, validated against experimental data to ensure accuracy. PCHIP numerical interpolation techniques were utilized to estimate aerodynamic coefficients across comprehensive angle-of-attack ranges not directly simulated. The optimized configuration demonstrated remarkable performance improvements, including a 75.68% increase in lift coefficient, an extension of the critical stall angle from 14° to 16°, enhanced aerodynamic efficiency, and significantly improved flow stability with reduced separation characteristics. These findings establish that the synergistic combination of internal slot and gurney flap modifications can fundamentally transform NACA 4412 aerodynamic performance, particularly excelling in high-angle-of-attack operational scenarios.
Robust Stochastic Model Predictive Control for Autonomous Vehicle Motion Planning Subiyanto, Subiyanto; Hangga, Arimaz; Bahatmaka, Aldias; Salim, Nur Azis; Sutrisno, Deyndrawan; Yunus, Elfandy; Budi Arif Prabowo, Setya; Hilmi Farras, Muhammad; Sanggrahita, Diadora
Jurnal Rekayasa Elektrika Vol 20, No 3 (2024)
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17529/jre.v20i3.39281

Abstract

This work presents a Robust Stochastic Model Predictive Control (RSMPC) framework for real-time motion planning autonomous vehicles, addressing the complex multi-modal vehicle interactions. The proposed framework involves adding expert policy from observations to the dataset and applying the Data Aggregation (DAgger) method to filter unsafe demonstrations and resolve expert conflicts. A Dual-Stage Attention-based Recurrent Neural Network (DA-RNN) model is integrated to predict dual class variables from the dataset, producing a set containing constraints collision-avoidance predicted to be active. The RSMPC framework enhances formulation optimization by eliminating irrelevant collision avoidance constraints, resulting in faster control signals. The framework is applied iteratively, continuously updating observations and solving the RSMPC optimization formulation in real-time. Evaluation of the DA-RNN model achieved a recall value of 0.97 and a high accuracy rate of 98.1% in predicting dual interactions, with a minimal false negative rate of 0.026, highlighting its effectiveness in capturing interaction intricacies. Validated through simulations of interactive traffic intersections, the proposed framework demonstrably excels, showing high feasibility of 99.84% and a 15-fold increase in response speed compared to the baseline. This approach ensures autonomous vehicles navigate safely and efficiently in complex traffic scenarios, paving the way for more reliable and scalable autonomous driving solutions.
Penerapan teknologi pengering pelet untuk peningkatan kualitas dan produksi pakan ternak di CV Sibad Engineering Semarang Bahatmaka, Aldias; Fitriyana, Deni Fajar; Darsono, Febri Budi; Wibowo, Muhammad Yusuf; Fahmi, Fiqri Fadillah; Hidayat, Indra Nurul; Buana, Lanang Puspa; Ghyferi, Andi Abdullah
KACANEGARA Jurnal Pengabdian pada Masyarakat Vol 8, No 1 (2025): Februari
Publisher : Institut Teknologi Dirgantara Adisutjipto

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.28989/kacanegara.v8i1.2576

Abstract

Pakan ternak merupakan faktor terbesar yang mempengaruhi produktivitas ternak. Dalam hal ini, mitra masih mengalami kendala dalam proses pengeringan pelet sebagai pakan ternak. Hal yang masih dilakukan dengan melakukan proses pengeringan pakan ternak terdahulu yaitu masih dilakukan secara konvensional dengan dijemur dibawah terik sinar matahari, sehingga tidak efektif dalam mengeringkan pakan ternak. Oleh karena itu perlu penerapan teknologi pengeringan dari hasil pengolahan pakan ternak menggunakan mesin rotary dryer. Mesin pengering dengan rotary dryer ini, pakan ternak dapat dikeringkan menggunakan drum pengering yang terbuat dari baja tahan karat dan dengan sistem kontrol komponen PLC. Hasil pengeringan menggunakan mesin pengering rotary dryer dihasilkan dalam bentuk serbuk atau butiran. Penerapan teknologi mesin rotary dryer ini dirancang untuk mencapai beberapa tujuan, termasuk meningkatkan efisiensi pengeringan pakan ternak dan meningkatkan kualitas dan produksi pakan ternak. Penerapan teknologi mesin pengering rotary dryer ini diharapkan dapat meningkatkan kualitas dan produksi pakan ternak di CV SIBAD Engineering Semarang.
NUMERICAL ANALYSIS OF MOUNTING BRACKET STRUCTURE ON THE DAMPING EFFECT OF STABILIZER STEERING DAMPERS Wibowo, Muhammad Yusuf; Bahatmaka, Aldias; Rusiyanto, Rusiyanto; Fitriana, Deni Fajar; Ghyferi, Andi Abdullah; Anwar, Ahmad; Ridananda, Ayyub; Chasan, Ahmad
Jurnal Rekayasa Mesin Vol. 16 No. 1 (2025)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/jrm.v16i1.1657

Abstract

Due to bumps or holes in the road, certain regions' road surface is still unsuitable for riding at high speeds. Many motorcycles used stabilizer steering dampers to reduce weave and wobble. Bracket is a structure that holds the stabilizer steering dampers to the motorcycle steering. Bracket plays a significant role in maintaining the stabilizer steering dampers as well as stopping any vibration due to the dynamic conditions. This paper presents Finite Element Analysis of a bracket, which is analyzed material aluminum 6061 and aluminum alloy cast. In this study, we have explored using Static Analysis to calculate the internal force, displacement, and stress of structural brackets. Hence in this study, we have performed Modal Analysis to determine the natural frequencies of the bracket for safety. And also, we have performed Transient Analysis to study the behavior of structure brackets over time in response to time-varying loads and vibrations in dynamic conditions.
PENGARUH MATERIAL TERHADAP DEFORMASI, STRAIN, DAN SAFETY FACTOR PADA BRACKET CALIPER MENGGUNAKAN METODE ELEMEN HINGGA Ghyferi, Andi Abdullah; Bahatmaka, Aldias; Wibowo, Muhammad Yusuf; Anwar, Ahmad; Ridananda, Ayyub; Vandika, Anggi
Jurnal Rekayasa Mesin Vol. 15 No. 3 (2024)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/jrm.v15i3.1700

Abstract

The purpose of this study is to analyze the deformation, equivalent elastic strain, and safety factor of a bracket bracket made from two different materials by using the Finite Element Method, specifically aluminum alloy 6061 T6 and cast iron EN GJL 100. The result of this study is that the Aluminum Alloy 6061T6 material has a deformation of 3.57E-04 whereas the Cast iron EN GJL 100 material is 2.75E-04. In the elastic strain equivalent test, the Aluminium alloy 6061 T6 material is 3.00-E07 and in the Cast Iron EN G JL 100 materials is 2.32E-07. In the safety factor test, Cast Iron En G J L 100 material was better than 1.8617 compared to the Alumium Alloys 60 61 T6 materials are 1.5125. This shows that Cast Iron E GJ L 100 materials are better in deformations, eqeuivalent elastic stations, and safety factors in this case.
STRUCTURAL ANALYSIS OF SEMI-SUBMARINE MONOHULL SHIP FOR TOURISM APPLICATIONS BY USING FINITE ELEMENT METHOD Hutagalung, Christian Imanuel; Bahatmaka, Aldias; Aryadi, Widya; Putrananda , Musdika Bagas Satria; Puteri, Berliana Ayarent
Jurnal Rekayasa Mesin Vol. 16 No. 1 (2025)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/jrm.v16i1.2020

Abstract

The research assesses the structural integrity of a semi-submersible monohull glass-bottom vessel designed for tourism, featuring a hull length of 9 meters. Finite Element Analysis (FEA) was employed to simulate five loading scenarios: full load, 75% capacity, 50% capacity, 25% capacity, and no load. The ship's structural basis was designated as the boundary condition. The peak equivalent stress under full load was 297.58 MPa, with validated values at 293.93 MPa. Additional scenarios demonstrated comparable concordance between FEA simulations and validations, with stress values spanning from 296.85 to 297.4 MPa and validation results ranging from 293.4 to 293.79 MPa. All calculated safety factors surpassed 2.25, guaranteeing adherence to SOLAS Chapter II-1 rules. The results validate that the ship's hull design complies with structural integrity norms under operational loads, instilling confidence in its performance for tourism purposes.
Capacity Building of Indonesian Migrant Workers in Korea for Post-Contract Preparation Cahyati, Widya Hary; Bahatmaka, Aldias; Putriningtyas, Natalia Desy
Jurnal Abdimas Vol. 28 No. 2 (2024): December 2024
Publisher : Universitas Negeri Semarang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/x2dsqv31

Abstract

Indonesian Migrant Workers (PMI) are Indonesian citizens working abroad. To meet economic needs, many Indonesian citizens choose to work abroad. The problem found in this service activity is that working abroad has many consequences, one of which is being away from family. However, if they return to Indonesia, Indonesian Migrant Workers (PMI) have concerns about the skills they have to work in Indonesia. For this reason, the solution offered to partner problems is socialization related to digitalization of entrepreneurship through the use of social media, as well as ways to market business products. The purpose of this activity is to increase PMI's capacity as a provision for preparation to make a living after the employment contract in Korea has ended. Thus, PMI can work in Indonesia and be close to family. The method of implementing the activity is to provide socialization with the target to the Indonesian Student Association (PPI) and Indonesian Migrant Workers (PMI) in Korea. The result of this service activity is an increase in knowledge, skills, and motivation from the participants, namely PPI and PMI. In addition, it also received a positive response from all participants. This socialization activity is expected to be carried out to Indonesian migrant workers in other countries.
Co-Authors Abdurrahman Abdurrahman Achmad Yanuar Maulana Agung Efriyo Hadi Agung Widodo Agustinus Purna Irawan Andi Abdullah Ghyferi Andriano, Kriswanto Anindya Ardiansari Antama Bahatmaka, Antama Anwar, Ahmad Ari Dwi Nur Indriawan Musyono Arimaz Hangga Arimaz Hangga, Arimaz Arrijah, Hanalinda Kubrus Asri, Sarwi Athanasius Priharyoto Bayuseno Azara, Salsa Bila Bahlawan, Zuhriyan Ash Shiddieqy Buana, Lanang Puspa Budi Arif Prabowo, Setya Budi Darsono, Febri Budi Chasan, Ahmad Cionita, Tezara Daffa Agya Mahardika Darsono, Febri Budi Deyndrawan Sutrisno Didik Supriadi Dony Hidayat Al-Janan Eko Sasmito Hadi Elfandy Yunus Fahmi, Fiqri Fadillah Fidia Fibriana Fiqri Fadillah Fahmi Fitriana, Deni Fajar Fitriyana, Deni Fajar Ghyferi, Andi Abdullah Godham Eko Saputro Hanif Hidayat Hendrix Noviyanto Firmansyah, Hendrix Noviyanto Herlin Pujiarti Hidayat, Hanif Hidayat, Indra Nurul Hilmi Farras, Muhammad Hutagalung, Christian Imanuel Hyoung Cho, Joung Hyung, Cho Joung Imam Pujo Mulyatno Imanu Danar Herunandi Irawaty Irawaty Irawaty Iskandar, Ranu Januar Parlaungan Siregar Karnowo - Khoirul Huda Kriswanto Kriswanto, Kriswanto Kurniawan, Ahmad Khusom Kusuma, Anwar Widjaya Laksono, Aryo Laksono, Aryo Eko Laksono, Galih Tri Leksono, Panggah Bowo Manalu, Janviter Markus Diantoro Mayangsari , Effelie Dewi Mera Kartika Delimayanti Muclisin, Choirul Anton Muhammad Habibullah Muhammad Hilmi Farras Muhammad Khumaedi Muhammad Yusuf Wibowo Natalia Desy Putriningtyas, Natalia Desy Nubli, Haris Nugroho Suhodo Nur Azis Salim Prasdika, Tegar Oki Puspitasari, Windy Desti Puteri, Berliana Ayarent Putrananda , Musdika Bagas Satria Putrananda, Musdika Bagas Satria Rafif Dimas Pratama Ramadhani, Risky Retnaningsih, Prihatini Ridananda, Ayyub Rifky Ismail Rizki Setiadi Rizqi Fitri Naryanto Rumapea, Fedrik Immanuel Rumondang, Juwita Ria Rusiyanto Rusiyanto Rusiyanto, Rusiyanto Salim, Nur Azis Samsudin Anis Sandi Pratama , Fajar Rizqi Sanggrahita, Diadora Sari, Linda Setiadi, Rizki Setya Budi Arif Prabowo Siregar, Januar Parlaungan Sonika Maulana Sucihatiningsih Dian Wisika Prajanti Sukoco, Imam Sunyoto Sunyoto Supriadi, Didik Sutrisno, Deyndrawan Syafei, M. Hilman Gumelar Tezara Cionita Vandika, Anggi Wara Dyah Pita Rengga Warsiti Warsiti Warsiti Warsiti Wibowo, Muhammad Yusuf Widya Aryadi Widya Hary Cahyati Winarko, Chandra Adi Wirawan Sumbodo Yunus, Elfandy