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The regenerative braking effectiveness of electric vehicles (EVs), with 8-25% range, requires designers to produce better braking systems. The antilock braking system (ABS) was chosen because it offers various advantages, such as enhanced safety considerations, vehicle maneuverability, and so on. The measurement findings revealed that ABS took longer to stop the wheels with the same wheel rotation speed. Because of the lesser differentiation of magnetic flux to time, it created lower induced emf in the generator. ABS 50 Hz performance was 19.5% at 4500 pm, whereas hydraulic brake performance was 21% at the same speed. ABS used model-based algorithms (MBAs) to boost the friction frequency with the wheels from 10 to 50 Hz. As the frequency increased, the ABS graph approached the hydraulic graph, and the ABS performance improved. Although ABS loses to hydraulics in stopping wheel rotation, it gains in saved energy and battery temperature. Longer wheel stop-times allow the rotational kinetic energy of the wheel more time to be converted into electricity.

Photoelasticity method was used to measure strain and stress fields to address the precision problem of determining fringe order of loading and cracking and notch areas. In this study, microscope was used as an additional tool in a photoelastic device for magnification of isochromatic fringe size. An experimental method was used by utilizing optical system and reflective polariscope. A simple compression tool was designed to provide a compression load on the solid disk-shaped specimens. Isochromatic fringe field was observed in the loading zone for different loading and captured image based on the following conditions: 9x, 15x and 20x without magnification and with magnification using SLR type Nikon camera Serie D3000. The image was processed using OpenCV software while C + + was used to produce clearer isochromatic fringe pattern formed on the surface of the specimen in the determination of the maximum fringe order observed. The average of additional fringe could be obtained as the optical magnification result. Data was analyzed using Finite Element Analysis Software. The result showed an increasing trend in fringe order with increasing levels of optical magnification. Its maximum value was obtained on20x optical zoom, which was 2-order fringe.

Deteksi penggunaan masker pada pengemudi kendaraan termasuk tugas klasifikasi yang dapat diselesaikan secara otomatis oleh kecerdasaan artifisial. Untuk implementasi pada perangkat mobile, arsitektur neural network MobileNetV2 dipilih dengan pertimbangan akurasi yang baik. Penambahan teknik data augmentation dan pemilihan optimizer ADAM semakin meningkatkan akurasi klasifikasi dari MobileNetV2. Proses deteksi dilakukan pada 13 foto pengemudi dengan masker dan 13 pengemudi tanpa masker. Untuk pengemudi tanpa masker, sistem pendeteksi berhasil 100%, meskipun ada salah satu kondisi saat pengemudi memakai masker di dagu, tingkat akurasi hanya sebesar 65,59%. Sedangkan untuk pengemudi tanpa masker, ada 1 foto yang salah, disebabkan oleh warna gelap yang digunakan sebagai masker, sehingga sistem pendeteksi mengklasifikasikan sebagai pengemudi tanpa masker dengan tingkat akurasi hingga 97,76%. Hasil analisis lebih dalam menunjukkan bahwa aksesoris seperti jilbab dan kacamata mempengaruhi tingkat akurasi yang dihasilkan oleh sistem pendeteksi. Sementara itu, tingkat akurasi juga lebih dipengaruhi oleh warna dari masker yang dipakai ketimbang pemilihan masker medis ataupun masker kain.

Asymmetric spur gear is used in one-way rotation transmission. This spur gear has a higher bending strength than symmetric spur gear. In this research, the effect of asymmetrical spur gear level on bending stresses is studied dynamically. The asymmetric spur gear level is expressed as asymmetric factor (K). Asymmetric factors K = 1, K = 1.05, K = 1.06, K = 1.07 and K = 1.08 are used. Dynamic analysis is performed by explicit dynamics numerical modeling. Material used for five asymmetric factor is AISI 1045. Two variables applied on this spur gears are torque loads and rotational speeds to investigate that effect on bending stress. Torque loads varied from 100 Nm to 250 Nm with 50 Nm increment and rotational speeds varied from 1000 rpm to 2500 rpm with 500 rpm increment. The results of this study show that the asymmetric factor can reduce more significantly bending stress cause of torque loads than cause of rotational speeds.

Magnetic gear is an alternative to mechanical gear, where the magnetic gear has the advantages of no noise, minimum vibration, no maintenance required, increased reliability, overload protection capability, no physical contact between gears, and the resulting torque density is still below the mechanical gear torque density. In this research, the variation of the number of poles and air gap in the amount of torque density produced was carried out. The permanent magnet material used is Neodymium type with a gear ratio of 1:2. In the variation of the number of poles used by pairs of 4 and 8 poles, 8 and 16 poles, 10 and 20 poles, and 12 and 24 poles, in the variation of the air gap used, namely 1 mm, 1.2 mm, 1.3 mm, 1.4 mm and 1.5 mm. Magnetic gear performance can be seen through analysis simulation with the 3D finite element method using Finite Elements Software. The type of simulation used is the magnetostatic analysis method at the processing stage and the transient analysis method at the post-processing stage. From the simulation results, it is concluded that the greater the number of poles, the greater the torque density produced, and the closer the air gap distance will result in a greater torque density. The effect of the number of poles on the torque density is more significant than the effect of the air gap.

Pada umumnya, sepeda yang beredar menggunakan Chain and Sprocket sebagai sistem pemindah daya utama. Sistem chain and sprocket sendiri mempunyai beberapa kelemahan. Dari kelemahan sistem chain and sprocket tersebut, maka pada penelitian ini dirancang sepeda chainless dengan menggunakan poros. Untuk penelitian ini, sepeda Chain and Sprocket dimodifikasi menjadi sepeda Chainless Zerol Bevel Gear. Lalu, pengujian efisiensi sepeda dilakukan untuk mengetahui besar efisiensi sepeda Chainless Zerol Bevel Gear dan dibandingkan dengan sepeda Chain and Sprocket. Sepeda dimodifikasi dengan menggunakan Zerol Bevel Gear 90 o pada bagian sistem pemindah daya dari pedal ke roda. Pengujian dilakukan dengan memberikan putaran pada poros pedal dengan motor listrik sehingga roda belakang ikut berputar. Putaran roda belakang diukur daya outputnya untuk mengetahui besar efisiensinya. Hasil dari penelitian ini didapat geometri Zerol Bevel Gear diproduksi dengan spesifikasi rasio total 1:1,33 , diameter poros 0,67 in, panjang poros 395 mm dan alat pengujian untuk menguji nilai efisiensi total sepeda. Dari hasil pengujian didapatkan nilai efisiensi tertinggi pada sepeda chain and sprocket dengan putaran pedal 55 rpm pada gear-2 internal hub dengan nilai efisiensi 89,92%. Sementara nilai efisiensi tertinggi pada sepeda chainless dengan putaran pedal 55 rpm pada gear-1 internal hub dengan nilai efisiensi 79,26%.

Roda gigi atau gear merupakan salah satu elemen mesin yang berfungsi untuk mentransmisikan daya. Sumber transimisi sebuah gear berasal dari kontak dan gesekan yang terjadi pada pasangan gear yang diteruskan oleh porosnya. Kontak dan gesekan yang terjadi merupakan sumber utama kegagalan pada roda gigi apabila dipadukan dengan kesalahan-kesalahan ( error ) dalam perancangan, assembly, dan machining roda gigi. Usaha yang dapat dilakukan untuk mengurangi masalah tersebut adalah dengan memodifikasi profil gigi dengan bentuk tip relief pada involute spur gear. Tip relief adalah pemotongan bagian flank pada roda gigi dengan bentuk parabolik dan linier. Material yang digunakan untuk penelitian ini adalah S45C. Simulasi regangan dinamis dilakukan dengan analisa Transient Structure , sedangkan analisa getaran dilakukan dengan analisa Harmonic Response pada software FEA. Hasil yang didapatkan dari penelitian ini adalah terjadi reduksi nilai regangan dan getaran pada profil modifikasi parabolik dan linier. Nilai reduksi yang terjadinya selanjutnya dibandingkan dengan hasil eksperimen dan didapatkan error dari simulasi yang dilakukan. Hasil dari penelitian ini diharapkan dapat menjadi solusi pada perindustrian terhadap kesalahan proses assembly dan machining yang terjadi pada pasangan roda gigi.

This Research is aimed to predict the maximum varying blank holder force (VBHF) over the punch stroke in order to eliminate cracks on cup deep drawing product. The constant blank holder force during the process, it's frequently not capable to prevent cracking, effectively. Using the slab method with assuming a constant volume of material, the simple analytical approach of maximum VBHF, has been conducted under the failure deformation and cracking criteria on every stage punch stroke. The cracking criteria are based on the maximum strength of materials. Steel sheet of SPCD grade, thickness 0.2 mm was used in this study. And the diameter of the cylindrical cup-shaped product was 40 mm. The analytic calculation of the maximum VBHF has been compared to FEM simulations, and its effects in the prevention of cracking. Analytical Results of maximum VBHF, not much different with FEM simulation. Compared to the application of the constant blank holder force, VBHF can be quite effective for preventing the occurrence of cracking and increasing the formability of deep drawing.

This paper aims to investigate the magnitude of minimum blank holder gap to prevent wrinkles and cracks defects of the rectangular cup with T4 material Tin Plate CA. Punch-die domensions are determined based on the standard tool designed. The methods of this research are an analytic, finite element (FE), and experimental approach, respectively. Each method in this study had been mutually compared to other methods. According to the research, minimum blank holder gap is recommended by 120% to 130% of the thickness of the initial material (about 0.24 A· 0.26 mm). By using the value of this gap, the height of wrinkles is very small, and the magnitude of the drawing force is still below the critical limit, so the product does not occur wrinkles and cracks.

This paper presents simulation of drawing force and thickness deformation in deep drawing which employs semi-active blank holder force system, to solve the problem of cracking and wrinkling. The method of slab with feed back control failure criteria, was employed to make the modeling system and the semi-active blank holder to prevent wrinkling and cracking in forming low carbon steel sheet, without lubrication (μ=0.4). In this study, the mechanical properties of the material were chosen since that they equivalent to those of low carbon steel with its thickness of 0.2 mm, k = 572 N/mm2, UTS = 391 N/mm2, yield stress = 309 N/mm2 and n = 0.2. The diameter and the depth of the cylindrical cup-shaped product were 40 mm and 10 mm, respectively. Results from simulation have shown that the semi-active blank holder system can control very responsive against changing of deformation condition. The optimum of initial blank holder force is approximately 3000 N up to 4000 N. In the early stages (initial stroke), blank holder force system could be responsive to prevent cracking, and at the end of the punch stroke, it is very effective to prevent wrinkling. Simulation of semi-active blank holder force control system is excellent in model formation to prevent cracking and wrinkling.

This paper presents the importance of simulation of metal flow in deep drawing process which employs an antilock brake mechanic system. Controlling the force and friction of the blank holder is imperative to assure that the sheet metal is not locked on the blank holder, and hence it flows smoothly into the die. The simulation was developed based on the material displacement, deformation and deep drawing force on flange in the radial direction, that it is controlled by blank holder with antilock brake mechanic system. The force to blank holder was applied periodically and the magnitude of force was kept constant during simulation process. In this study, the mechanical properties of the material were choses such that they equivalent to those of low carbon steel with its thickness of 0.2 mm. The diameter and the depth of the cylindrical cup-shaped product were 40 mm and 10 mm, respectively. The simulation results showed that the application of antilock brake mechanic system improves the ability to control the material flow during the drawing process, although the maximum blank holder force of 13000 N was applied. The optimum condition was found when the drawing process was performed using blank holder force of 3500 N, deep drawing force of 7000 N, friction coefficient of 0.25 and speed of punch stroke of 0.84 mm/sec. This research demonstrated that an antilock brake mechanic system can be implemented effectively to prevent cracking in deep drawing process.

Seiring perkembangan zaman, teknologi roda gigi dituntut untuk mampu mentransmisikan daya yang besar dengan efisiensi yang besar pula. Pada jenis intersecting shaft gear, tipe roda gigi payung spiral (spiral bevel gear) merupakan perkembangan dari roda gigi payung bergigi lurus (straight bevel gear). Kelebihan dari spiral bevel gear antara lain adalah kemampuan transmisi daya dan efisiensi yang lebih besar pada geometri yang sama serta tidak terlalu berisik. Akan tetapi spiral bevel gear juga mempunyai kelemahan jika dibandingkan dengan straight bevel gear. Selain proses manufaktur yang lebih rumit, profil lengkung gigi spiral ini membuat distribusi tegangan yang terjadi menjadi lebih rumit untuk dimodelkan dengan persamaan matematika. Salah satu pendekatan yang dapat dilakukan adalah dengan menggunakan metode elemen hingga. Penelitian diawali dengan membuat model dari straight bevel gear dan juga spiral bevel gear yang sudut spiralnya divariasikan 20, 35, dan 45 derajat. Model dibuat dengan dimensi yang sama baik diameter maupun jumlah gigi gear. Langkah selanjutnya yaitu perhitungan analitis pada straight bevel gear dimana hasilnya akan dibandingkan dengan hasil simulasi statis. Setelah eror yang terjadi dibawah 15% maka dilakukan simulasi dinamis pada semua model yang telah dibuat yaitu straight bevel dan juga spira bevel gear. Hasil yang didapatkan dari penelitian ini adalah secara keseluruhan spiral bevel gear lebih kuat daripada straight bevel gear pada dimensi dan beban yang sama jika dilihat dari lebih kecilnya tegangan bending dan tegangan kontak maksimum yang terjadi. Tegangan terbesar terjadi pada jenis straight bevel gear baik pada tegangan bending maupun tegangan kontak sedangkan spiral bevel gear dengan variasi sudut Seiring spiral 35 mempunyai nilai tegangan terkecil. Prosntase selisih tegangan bending maksimum yang terjadi antara straight bevel gear dan spiral bevel gear dengan variasi sudut spiral 35 derajat sebesar 44,3%. Sedangkan selisih tegangan kontak maksimumnya sebesar 20,5%. Sehingga secara keseluruhan spiral bevel gear lebih baik daripada straight bevel gear. Kata Kunci- spiral bevel gear, tegangan bending, tegangan kontak, FEM.

This paper presents the mathematical approach of minimum blank holder force to prevent wrinkling in deep drawing process of the cylindrical cup. Based on the maximum of minor-major strain ratio, the slab method was applied to determine the modeling of minimum variable blank holder force (VBHF) and it compared to FE simulation. The Tin steel sheet of T4-CA grade, with the thickness of 0.2 mm was used in this study. The modeling of minimum VBHF can be used as a simple reference to prevent wrinkling in deep drawing.

In this paper, we discuss comparation of vehicle vibration energy harvesting between rotary and linear electromagnetic generator. We construct the two model of energy harvester mechanism and then analyze both of energy absorbtion and vehicle comfortability. Furthermore, we analyze both of energy absorbtion and vehicle comfortability. Vehicle is modeled as quarter car. Rotarty generator harvests 2.5 x 10-4 Watt. The other hand, linear generator has viscous characteristic and capable to generates 90 Watts with 12 Volt power supply for 0.03 m amplitude of bumpy road input. Linear generator reduces oscillation with 1.2 sec settling time. It is more comfort than the angular which has 3 sec in settling time. With unnevenees road input, mean power of this generator is 64 Watt.

Motorcycle in its operation needs high stability. To improve a stability of motorcycle especially in turning direction is done by many methods. The handling turn inclination angle of motorcycle with addition gyroscopic component will be discussed in this research. Gyroscopic is systems which have function to against from Centrifugal (Fc) force. The aim of using Gyroscopic is to control and handling turn inclination angle to avoid skidding.This research uses of simulation model with input of design and dynamic parameter. Speed variable to be used are 40, 50, 60, 70, 80, 90, 100 km/hour. The simulation is processed by Matlab 7.0.1. The result of research is concluded as : the Gyroscopic has controlled skid performance and inclination angle of motorcycle about 11%.