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All Journal Sinergi Kinetik: Game Technology, Information System, Computer Network, Computing, Electronics, and Control JCES (Journal of Character Education Society) Jurnal Teknik Mesin Indonesia Mekanika: Majalah Ilmiah Mekanika Indonesian Journal of Electrical Engineering and Computer Science International Journal of Sustainable Transportation Technology SEMAR Journal of Electrical, Electronic, Information, and Communication Technology (JEEICT) Wiga : Jurnal Penelitian Ilmu Ekonomi Automotive Experiences
Ubaidillah
Department Of Mechanical Engineering Universitas Sebelas Maret, Surakarta
Aerospace Engineering Humanities Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Materials Science & Nanotechnology Mechanical Engineering Social Sciences Transportation

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An Innovative Design of Magnetorheological Lateral Damper for Secondary Suspension of a Train Masa'id, Aji; Ubaidillah, Ubaidillah; Lenggana, Bhre; Muhayat, Nurul; Wibowo, Wibowo; Mazlan, Saiful
http://dx.doi.org/10.31427/IJSTT.2019.2.2.2
Publisher : Unijourn Publisher

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Abstract

This article delivered an innovative idea of a magnetorheological (MR) damper for secondary suspension of train bogie. The valve inside MR damper adopted meandering of both fluid flow and magnetic flux for improving magnetization area. In this work, the design and working principle of the MR valve were presented including a mathematical model to predict the pressure drop. In the early stage, the finite element method magnetics software (FEMM) simulation could predict the magnetic flux density across the passages. Based on the amount of magnetic flux, the corresponding shear yield stress could be determined from its basic physical properties. The mathematical model covered pressure drop prediction for both off-state and on-state. The FEMM simulation results showed that the meandering flow and serpentine flux design could improve the effective area of magnetization. Consequently, the pressure drop of the valve could have wider ranges and achieve a high value of pressure differences. This result could be potentially improving the performance of the damping forces of the lateral damper in a bogie train.
Effect of Curing Current on Stiffness and Damping Properties of Magnetorheological Elastomers Hapipi, Norhiwani; Mazlan, Saiful; Aziz, Siti; Ubaidillah, Ubaidillah; Mohamad, Norzilawati; Yazid, Izyan; Choi, Seung-Bok
http://dx.doi.org/10.31427/IJSTT.2018.1.2.3
Publisher : Unijourn Publisher

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Abstract

In this study, the viscoelastic effects of the magnetic field strength imposed for curing process on the stiffness and damping properties of magnetorheological elastomers (MREs) are experimentally investigated. In order to observe the effect, three different samples of MRE are fabricated by imposing curing current of 0.1 A, 0.3 A and 0.5 A which is equivalent to the magnetic field of 70 mT, 309 mT, and 345 mT, respectively. All samples consist of 30% silicone rubber and 70% carbonyl iron particles (CIPs) by weight percentages. After observing the morphological images via SEM, the dynamic performances of these samples, such as storage modulus and loss factor are evaluated and compared as a function of the magnetic field intensity or oscillation frequency. It is shown that the sample cured at 0.5A exhibits the highest storage modulus in the frequency domain. In addition, MR effects of three samples are identified, and it is found that the sample cured at 0.5A shows the highest absolute and relative MR effect.
Studi simulasi distribusi panas pada panci kukus alat pemercepat pengasinan telur otomatis Ubaidillah Ubaidillah; Nicholas Arga Vino Dewangga; Arifin Nurcholis; Yogie Muhammad Lutfi; Damaris Adi Waskitho; Skolastika Grace Harjaningtyas
Jurnal Teknik Mesin Indonesia Vol 16 No 2 (2021): Jurnal Teknik Mesin Indonesia
Publisher : Badan Kerja Sama Teknik Mesin Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36289/jtmi.v16i2.255

Abstract

Perpindahan panas adalah perpindahan energi akibat adanya perbedaan suhu di antara dua tempat yang berbeda. Bahasan utama dalam perpindahan panas ialah cara energi di dalam panas dapat berpindah tempat dan laju perpindahannya dalam kondisi tertentu. Perpindahan panas meliputi proses pemasukan dan pengeluaran panas. Kajian ini berisi desain teknik dan simulasi distribusi panas pada panci kukus alat pemercepat proses osmosis telur dengan memanipulasi tekanan osmotik (hidrostatik) dengan nyala kompor. Alat yang dimaksud berupa panci kukus dengan dudukan dan kompor pemanas yang diletakkan 2,5 inchi dari panci. Pertama, alat ini didesain menggunakan software 3D engineering drawing, metode oven dengan pembakaran sabut kelapa pada alat pengasin telur sebelumnya diubah menjadi metode kukus dengan nyala api kompor untuk menjaga suhu tetap stabil. Metode pengukusan (steaming) dipilih karena dapat mempertahankan cita rasa alami dari bahan makanan dengan terjadinya perpindahan panas secara konveksi dari uap panas ke bahan makanan yang sedang dikukus. Analisis perambatan panas menggunakan metode elemen hingga menggunakan software ANSYS untuk mengetahui kemampuan distribusi panas pada panci, serta untuk mengetahui bagian yang ikut panas saat alat bekerja, sehingga dapat dilakukan insulasi. Simulasi dilakukan dengan memberikan panas steady pada permukaan bawah panci kukus dengan suhu api sebesar 1200°C. Desain berulang kali dilakukan perbaikan untuk meningkatkan kekuatan dan penyebaran panas di daerah kritis dengan cara mengubah material dan mengubah metode pemanasan, sehingga didapat hasil yang baik untuk suhu pemanasan telur yang stabil. Desain difinalisasikan untuk proses pembuatan produk. Kajian ini dibuat sebagai bentuk pengembangan pemodelan alat masak dan sistem yang optimal pada alat pengasin telur dalam bentuk publikasi jurnal ilmiah.
Perpindahan panas secara konveksi pada magnetorheological fluid: Review Zeluyvenca Avista; Ubaidillah Ubaidillah; Zainal Arifin; Indri Yaningsih
Jurnal Teknik Mesin Indonesia Vol 16 No 1 (2021): Jurnal Teknik Mesin Indonesia
Publisher : Badan Kerja Sama Teknik Mesin Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36289/jtmi.v16i1.196

Abstract

Magnetorheological fluid (MRF) merupakan cairan magnet yang mempunyai sifat dari cair menjadi hampir padat dibawah medan magnet eksternal. Bahan pembentuk MRF berupa fluida dasar, partikel padat, dan aditif. Review artikel ini difokuskan pada perpindahan panas konveksi yang terjadi dalam MRF. Kajian mengenai perpindahan panas konduksi pada MRF baik simulasi numerik maupun eksperimental sudah banyak dilakukan sebelumnya namun kajian pada perpindahan panas secara konveksi untuk MRF masih sangat jarang ditemukan. Sehingga pada review artikel ini akan dilakukan peninjauan pada ferrofluid, nano fluid dan elektrorheological fluid. Dengan peninjauan pada kajian konveksi di fluida magnet tersebut, maka pada hal serupa juga dapat diterapkan untuk studi mengenai perpindahan panas secara konveksi pada MRF.
Magnetorheological elastomers berbasis lateks cair sebagai matriks utama Virel Wibawa; U Ubaidillah
Jurnal Teknik Mesin Indonesia Vol 14 No 2 (2019): Jurnal Teknik Mesin Indonesia
Publisher : Badan Kerja Sama Teknik Mesin Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (673.639 KB) | DOI: 10.36289/jtmi.v14i2.133

Abstract

This study tells about isotropic MRE with latex as the matrix, variation on the mass fraction of CI particle (wt%) and evaluate the following characteristics, such as density, hardness, break stress, elongation and swelling of the variation ratio mixture of MRE with the latex matrix. In this study use 0, 30, 40, 50, 60 and 70 wt% as the MRE composition, held in Laboratorium Pusat Penelitian Karet Indonesia which has the standardized rubber testing in yield strength, hardness and swelling in Indonesia. Pure latex with 0,94 gr/cm3 in density, improvement above 100% happens when CI particle added as much as 40%. The amount of CI particle made the rising of hardness point as much as 15 point from 35 when CI particle added as much as 70%. The add of CI particle cause a decresing of tensile stress, it’s seen when pure latex has 14,5 MPa in tensile testing and breakdown until 760%. When CI particle added as much as 70%, the break stress decrease until 2 MPa and the breakdown in 610%. Volume changes when the pure latex sink in the ASTM OIL 3 liquid, the volume increase as much as 167,94% and still increase almost 100% in 305,97% when CI particle 70% added.
BUDIDAYA JAMUR TIRAM BERBASIS TEKNOLOGI UNTUK KEMANDIRIAN MASYARAKAT DESA BAKALAN, KABUPATEN KARANGANYAR Catalina Dara Ayu Az-Zahra; Ammar Abdurrohman; Cakram Yudhifa Ganda Satriawan; Nadiya Nur Aini; Tri Rahmaji; Ubaidillah Ubaidillah
JCES (Journal of Character Education Society) Vol 4, No 4 (2021): Oktober
Publisher : Universitas Muhammadiyah Mataram

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31764/jces.v4i4.4859

Abstract

Desa Bakalan, Jumapolo, Karanganyar, Jawa Tengah merupakan penghasil komoditas beras yang cukup melimpah dengan jumlah 1,92% dari hasil keseluruhan panen di Kabupaten Karanganyar, maka dari itu dihasilkan juga limbah jerami dalam jumlah banyak yang mencapai 1.621,08 Ton. Di masa pandemi COVID-19, banyak masyarakat Desa Bakalan kembali dari merantau, sehingga tingkat pengangguran semakin bertambah dan tingginya jumlah pengangguran usia produktif serta adanya suatu perkembangan IPTEK masa revolusi industri 4.0, maka faktor tersebut yang mendorong kami untuk menciptakan inovasi pertanian yang memanfaatkan teknologi zero waste dalam budidaya jamur tiram sebagai lapangan pekerjaan baru, sehingga limbah jerami tidak hanya digunakan untuk pakan ternak. Dalam keberjalanan program, kami menggunakan metode pengabdian secara daring (dalam jaringan) dan luring (luar jaringan) dimulai dari terbentuknya kelompok tani “Kedarsi” untuk selanjutnya dilaksanakan proses pelatihan. Setelah pelatihan dilaksanakan persiapan pembelian alat dan bahan dan dilanjutkan proses produksi baglog jamur tiram dengan jumlah 2500 serta dibuatnya alat pengatur suhu dan penyiraman secara otomatis dalam mendukung proses bududaya jamur.
Aerodynamic Characteristics of Ahmed Body with Inverted Airfoil Eppler 423 and Gurney Flap on Fastback Car Zainal Arifin; Suyitno Suyitno; Dominicus Danardono Dwi Prija Tjahjana; Wibawa Endra Juwana; Rendy Adhi Rachmanto; Chico Hermanu Brillianto; Ubaidillah Ubaidillah; Singgih Dwi Prasetyo; Arinal Falah Muhammad; Mohd Afzanizam Mohd Rosli
Automotive Experiences Vol. 5 No. 3 (2022)
Publisher : Universitas Muhammadiyah Magelang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31603/ae.7067

Abstract

The installation of aerodynamic devices, such as rear wings with the application of a Gurney flap, is very important to improve the performance of vehicles and can generate downforce and reduce slip when a car turns and brakes. The goal of this study was to determine the aerodynamic characteristics of the addition of a rear wing using an Eppler 423 airfoil, which was applied with a Gurney flap featuring variations in the angle of attack and the height of the Gurney flap. The rear wing was mounted on the Ahmed body with a rear slant angle of 15°, which is similar to the configuration on a fastback type car. This research was conducted by 3D modeling through computational fluid dynamics (CFD) simulation using ANSYS Student R18.2 by using ahmed body design. There are three variations in the angle of attack for the rear wing (0°, 7.5°, and 15°), as well as five variations in Gurney flap height of 0%, 0.5%, 1%, 1.5%, and 2% for the chord-line length. In this study, the best variation was found at an angle of attack of 15⁰ with a height of 2% C. From this configuration improved CL/CD ratio by 25.36% when compared to the results without a Gurney flap.
Design and simulation of a combined serpentine t-shape magnetorheological brake Faishal Harish Hidayatullah; Ubaidillah Ubaidillah; Endra Dwi Purnomo; Dominicus Danardono Dwi Prija Tjahjana; Ilham Bagus Wiranto
Indonesian Journal of Electrical Engineering and Computer Science Vol 13, No 3: March 2019
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v13.i3.pp1221-1227

Abstract

A magnetorheological brake (MRB) is a device to dissipate rotational energy using magnetorheological fluids (MRF). MRB can change its braking torque quickly in response to external magnetic field strength. The brake is rotational, utilizing the MRF in shear mode. In this study, the geometrical design of the MRB, magnetic circuit and MRF flow path is addressed. Mathematical models are presented that describe the braking torque of the MRB. A novel prototype is introduced combining T-shape rotor model with serpentine flux magnetic circuit configuration. The rotor member is selected to direct the flux concentration at that location. Serpentine flux configuration is selected to achieve higher torque without increasing the size of MRB by activated more surface area of MRF with the magnetic flux. The finite element method is used to evaluate the magnetic flux density in MRB using FEMM 4.2. FEMM results showed that this novel design could provide sufficient magnetic flux along MRF flow path. Finally, the influence of input current to the MRB on braking torque is investigated. It is found that the braking torque in MRB increases with the increase of the input current. The prototype is formulated as foot-drop prevention orthotic. The MRB would be further integrated into ankle-foot orthoses for post-stroke patients. The design is formulated as a preliminary geometrical design, aiming to obtain the minimum required braking torque.
Comparing the linear and logarithm normalized extreme learning machine in flow curve modeling of magnetorheological fluid Irfan Bahiuddin; Abdul Y Abd Fatah; Saiful A Mazlan; Mohd I Shapiai; Fitrian Imaduddin; Ubaidillah Ubaidillah; Dewi Utami; Mohd N Muhtazaruddin
Indonesian Journal of Electrical Engineering and Computer Science Vol 13, No 3: March 2019
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v13.i3.pp1065-1072

Abstract

The extreme learning machine (ELM) plays an important role to predict magnetorheological (MR) fluid behavior and to reduce the computational fluid dynamics (CFD) calculation cost while simulating the MR fluid flow of an MR actuator. This paper presents a logarithm normalized method to enhance the prediction of ELM of the flow curve representing the MR fluid rheological properties. MRC C1L was used to test the performance of the proposed method, and different activation functions of ELMs were chosen to be the neural networks setting. The Normalized Root Mean Square Error (NRMSE) was selected as the indicator of the ELM prediction accuracy. NRMSE of the proposed method is found to improve the model accuracy up to 77.10 % for the prediction or testing case while comparing with the linear normalized ELM
Preliminary experimental evaluation of a novel loudspeaker featuring magnetorheological fluid surround absorber Endra Dwi Purnomo; Ubaidillah Ubaidillah; Fitrian Imaduddin; Iwan Yahya; Saiful Amri Mazlan
Indonesian Journal of Electrical Engineering and Computer Science Vol 17, No 2: February 2020
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v17.i2.pp922-928

Abstract

A novel design of magnetorheological fluids (MRF) based surround device in a loudspeaker system was studied in this article. The main objective of this research is to design a new surround device of the loudspeaker that can be easily controlled its damping. Therefore, it was predicted that the audio pressure level on the loudspeaker could be easily manipulated at a different sound source by applying a certain magnetic field. This function could not be reached using one conventional speaker system. Firstly, a set of an electromagnetic device containing MRF was designed to replace the conventional rubber surround. The magnetic circuit was then evaluated using the finite element method magnetics to study the flux distribution in the MRF area. The current was varied from 0.25 to 0.75 A by an interval of 0.25 A. The magnetic flux resulted from the simulation was then logged and used as the based value for predicting the change of shear yield stress. The base properties of the shear yield stress of the MRF against the magnetic flux was obtained from previous experimental result. Therefore, it was hopefully the prediction could be closed to the real system. Based on the simulation result, the shear yield stress varied from 43 to 49 Mpa or about 15 % increment. A simple experimental work was carried out. By applying particular direct current into the coil, the sound quality generated by the loudspeaker shows different values. Based on the preliminary experiment, the level of decibel decreased about 3 dB as the application of magnetic fields. The idea has been proven in this preliminary experimental evaluation.
Co-Authors Abdul Y Abd Fatah Adiputra, Dimas Aditya Rio Prabowo Agung Tri Wijayanta Agus Sartomo Ammar Abdurrohman Andi Nur Halisyah Arifin Nurcholis Arinal Falah Muhammad Arjon Turnip Aziz, Siti Azma Putra Bagas Wahyu Prakoso Bahiuddin, Irfan Bambang Kusharjanta Bhre Wangsa Lenggana Budi Kristiawan Budi Santoso Budi Santoso Cakram Yudhifa Ganda Satriawan Catalina Dara Ayu Az-Zahra Chico Hermanu B.A. Choi, Seung-Bok Damaris Adi Waskitho Danardono Dwi Prija Tjahjana, Dominicus Dewi Utami Diasdamara Fakhri Nugroho Didik Djoko Susilo Dimas Wahyu Utomo Dwi Aries Himawanto Dwi Prasetyani Eko Prasetya Budiana Elliza Tri Maharani Endra Dwi Purnomo Endra Dwi Purnomo Fahri Setyo Utomo Faishal Harish Hidayatullah Faiz Nur Fauzi Fajar Budi Laksono Fitrian Imaduddin Fitrian Imaduddin Fitrian Imaduddin Fitrian Imaduddin Hananta Diatmaja Hapipi, Norhiwani Hari Sulistiyo Budi Waspada Haris Nubli Ilham Bagus Wiranto Indri Yaningsih Indri Yaningsih Irfan Bahiuddin Irianto Irianto Iwan Yahya Kacuk Cikal Nugroho Lenggana, Bhre Masa'id, Aji Mazlan, Saiful Mazlan, Saiful Meiyanto Eko Sulistyo Mohamad, Norzilawati Mohd Afzanizam Mohd Rosli Mohd I Shapiai Mohd N Muhtazaruddin Muhammad Ilman Nur Sasongko Muhammad Ilman Nur Sasongko Muhammad Nizam Muhayat, Nurul Nadiya Nur Aini Nicholas Arga Vino Dewangga Noval Fattah Alfaiz Oki Muraza Priyandoko Gigih Purbo Suwandono Purbo Suwandono Rahmad Rizki Nur Arifin Rahmad Rizki Nur Arifin RAHMAWATI RAHMAWATI Ratna Endah Santoso Raymundus Lullus Lambang Govinda Hidajat Rendy Adhi Rachmanto Reza Humaidi Rizqi Husain Alfathan Rum Handayani Rumi Iqbal Doewes, Rumi Iqbal Saiful A Mazlan Saiful Amri Mazlan Saiful Amri Mazlan Satria Auliansyah Sigit Tri Wicaksono Singgih Dwi Prasetyo Singgih Dwi Prasetyo Siti Nurlela Skolastika Grace Harjaningtyas Suyitno - Suyitno Suyitno Syamsul Hadi Teguh Muttaqie Tri Rahmaji Ully Asfari Virel Wibawa Wibawa Endra Juwana, Wibawa Endra Wibowo Wibowo Wibowo, Wibowo Wijang Wisnu Raharjo Yazid, Izyan Yogie Muhammad Lutfi Zainal Arifin Zainal Arifin Zainal Arifin Zainal Arifin Zeluyvenca Avista