Indonesia Conference Directory

Corresponding Author
Teresa Nirmala

Institutions
1) Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung (ITB), Jalan Ganesha 10, Bandung 40132, Indonesia
2) National Center for Sustainable Transportation Technology (NCSTT), Jalan Ganesha 10, Bandung 40132, Indonesia

*Corresponding e-mail: teresanirmala21[at]gmail.com

Abstract
With the growing size of the electric vehicle (EV) market, the study of the battery system is paramount. Lithium-ion batteries have a high risk of flammability in the event of an accident or a collision that causes a short circuit. One of the highest potential threats to EVs is ground impact from stones or projectiles impingement that can hit and penetrate the battery pack. Therefore, it is necessary to develop a lightweight structure that can protect batteries in the event of dynamic impact load. The material used for the protection structure is fiber metal laminate (FML), which is a hybrid material consists of thin metal layers bonded together by intermediate composite. Evaluation of the risk of battery fire due to short circuit (battery shortening) and energy absorption of the protection structure is done by using the nonlinear finite element method. Parametric studies were conducted to investigate the effect of thickness, bonding strength, as well as two damage parameters such as failure and softening effect. Simulation results show that increasing the softening parameter can increase energy absorption but also increase the battery shortening. While increasing all the other parameters can increase energy absorption and reduce battery shortening. In this study, the most effective design for the protection structure was obtained, which is 1 mm-thick aluminum as the top and bottom layer, and 4.8 mm-thick carbon fiber reinforced polymer (CFRP) as the intermediate layer.

Keywords
Crashworthiness; Electric vehicles; FML; Ground impact

Topic
Lightweight Structure

Link: https://ifory.id/abstract/DaEQBYVp8mhf

Corresponding Author
Gilang Farhan Ramadhan Mulyadi

Institutions
Institut Teknologi Bandung

Abstract
Abstract—Crashworthiness criteria attention in structural vehicle has increased by government to make the road safer, leading towards to laws and investment to investigation. In order to improve the crashworthiness and energy absorption performance of electric vehicles, the multi cell platform introduced as application in designing crash box. Multi cell platform can increased the energy absorption of crash box. Designing multi-cell platform needs the cell configuration and the cell number. Various type of cell configuration and number show difference behavior. It is needs to be studied comprehensively in order to gain desired design criteria. This paper studied the behavior of various type of multi-cell platform. The configuration divided into cruciform shape, H-shaped, T-shaped and Y-shaped. The crash box subjected under axial load in low velocity of quasi-static mode. The simulation results show that the cell configuration and cell number have different results. Increasing the number of cell and intersection can result in higher energy absorption but detrimental due to peak force.

Keywords
multi-cell, crash box, axial impact, crashworthiness, energy absorption

Topic
Lightweight Structure

Link: https://ifory.id/abstract/Kj9AWU6fmLMZ

Corresponding Author
Robby Robby

Institutions
a) Mechanical Design Research Group, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia
*hrobbyz[at]hotmail.com
b) Lightweight Structures Research Group, Faculty of Mechanical and Aerospace Engineering, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia
c) National Center for Sustainable Transportation Technology, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung 40132, Indonesia

Abstract
Lightweight structure such as thin-walled column is adapted in electric vehicle as an energy absorber. It is also used to reduce the weight of the vehicle so it can reduce the energy consumption. Most researches focus on uniaxial loading whereas, in practice, biaxial loading is likely to occur. Researches also show that a multi-cell column performs better in crashworthiness compared to conventional or single-cell column. This research aims to conduct numerical simulations of the multi-cell thin-walled column subjected to biaxial loadings. Numerical simulations have been done to five different cross-section aluminium square columns: single-cell (V0H0); multi-cell with one vertical plate (V1H0); multi-cell with two vertical plates (V2H0); multi-cell with one vertical and one horizontal plates (V1H1); and multi-cell with two vertical and one horizontal plates (V2H1). V2H1 column performs high specific energy absorption when it is subjected to fully axial and axial-dominant loadings. It absorbs up to 69.07% more than single-cell column does. On the other hand, V2H0 column performs high specific energy absorption when it is subjected to fully bending and bending-dominant loadings. It absorbs up to 99.56% more than single-cell column does.

Keywords
Biaxial loading; Crashworthiness; Energy absorber; Multi-cell; Thin-walled structure

Topic
Lightweight Structure

Link: https://ifory.id/abstract/Ph6MeGv7NdEp

Corresponding Author
Andi Idhil Ismail

Institutions
a) Mechanical Engineering, Institut Teknologi Kalimantan
Jl. Soekarno Hatta KM 15, Balikpapan, Kalimantan Timur, 76127
*a.idhil[at]itk.ac.id
b) National Center for Sustainable Transportation Technology (NCSTT), Bandung
c) Material and Metallurgy, Institut Teknologi Kalimantan, Jl. Soekarno Hatta KM 15, Balikpapan, Kalimantan Timur, 76127
*gusti.unt[at]itk.ac.id

Abstract
Machining of titanium alloys remains a challenging task due to its low thermal conductivity and other inheritance properties. This phenomenon often causes the reduction of tool life, increasing production cost and time. Several factors play role in determining the tool life such as cutting speed, feed, chip formation, and tool geometry. The current work investigates the effect of tool geometry and feed to the cutting temperature, force, and chip formation. Finite element method (FEM) is implemented to model orthogonal cutting process in the titanium alloy (Ti6Al4V). We use Johnson-Cook (J-C) material constitutive model and Johnson-Cook (J-C) fracture-damage model to simulate the process. Our results demonstrate that at the rake angle of 0° the cutting force and cutting temperature reach maximum value of 490 °C. The temperature decreases to around 370 °C if the cutting rake angle changes to 10°. Feed seems to have low impact in the temperature. The effect of feed and rake angle is more pronounced in the cutting force.

Keywords
Ti-6Al-4V; Machining; Finite Element Method

Topic
Lightweight Structure

Link: https://ifory.id/abstract/FDj34xYJCuhM

Corresponding Author
Raynald Masli

Institutions
(a) Department of Aerospace Engineering, Bandung Institute of tecnology, Jalan Ganeca No. 10, Bandung 40132, Indonesia
*masliray20041997[at]gmail.com
(b) Department of Mechanical Engineering, Bandung Institute of tecnology, Jalan Ganeca No. 10, Bandung 40132, Indonesia

Abstract
As a form of transportation mode, railway vehicle must be able to protect passengers from fatalities while accidents occur. For that purpose, some parts of the vehicle are designed to dissipate impact energy and to guarantee passengers protection. This paper presents study on the performance improvement of impact energy absorbing system on light rail transit (LRT) by implementing an array of rectangular column crash boxes system. Numerical simulations were carried out with finite element method in order to evaluate response of the structures subjected to axial impact loads based on the International regulation, UIC/EN 15227. The crashworthiness performance of proposed design was then compared to those of the baseline system which used C-channel crash boxes. The systems performance indicators are the weight reduction and crashworthiness parameters. The simulations results showed that the proposed design is better since it is 42 kg lighter and from 5 crashworthiness parameters, 4 are improved.

Keywords
crashworthiness; light rail transit; collision; rectangular crash boxes; structural efficiency

Topic
Lightweight Structure

Link: https://ifory.id/abstract/Dh8GFd4KABEH

Corresponding Author
Daniel Irawan

Institutions
Institut Teknologi Bandung (ITB)

Abstract
The research in the electric vehicle requires a safe Reserved Energy Storage System (RESS) that is durable and crashworthy enough to withstand a harsh environment, especially ground impact from stone chips on the road. RESS, which typically uses lithium-ion type battery, is posed to the jeopardy of thermal runaway as an aftermath of intrusion into the cell body. Thermal runaway might happen because the separator between the anode and cathode spoil and fail to keep both from making contact that results in a short circuit. Nowadays, metallic structures have been applied underneath the cells to protect RESS, although not so useful. Not just the extra mass, it cannot hold the impact properly. This research focuses on a composite-based protective layer applying sandwich panel structures for a stiffer layer. Conducted using non-linear finite element analysis with LS-DYNA solver, this research takes multiple design variables into accounts such as layer thickness, topology, and orientation while maintaining the base material of plain weave Carbon Fiber Reinforced Polymer (CFRP). The variables that are set as performance indicators are mainly cell deformation and energy absorbed. Among the two topologies tested, Navy Truss is proven to get along better with composite material than Blast Resistant Adaptive Sandwich (BRAS) model. This occurs since the Navy Truss absorbs energy by undergoing progressive crushing, BRAS structures collapse within the supports. In the Navy Truss itself, various orientations are tested, and it is found that the most effective orientation is [(0/90)2/[(45/-45)/(0/90)]3]s. Compared to the metallic structure, profusely there has been 36 percent mass saving.

Keywords
crashworthiness, sandwich panel, composite, CFRP, NavTruss, BRAS, RESS

Topic
Lightweight Structure

Link: https://ifory.id/abstract/pcLUFKq9yxEB

Corresponding Author
Mohd Shukri Yob

Institutions
UTeM

Abstract
In the automotive industry, thin-walled chassis is widely used due to high strength and stiffness-to-weight ratio. For a vehicle, the functions of chassis are to carry loads, protect passengers and cars components. Since the chassis is the heaviest part for a vehicle, it must be designed with higher strength and stiffness-to-weight ratio to produce energy-efficient vehicle (EEV). For a chassis, its strength and stiffness greatly depend on the joint stiffness. In automotive production, chassis is formed by joining thin-walled beams using the welding technique. However, it will expose this chassis to buckling and joint flexibility effect that will reduce its strength and stiffness. In this research paper, the effect of vertical gusset plate to the stiffness of the thin-walled chassis will be carried out using the experimental method under bending and torsional loads. From these experiments, it is found that the bending stiffness increases by about 25.45% while torsional stiffness increases 84.75% when vertical gusset plates are introduced. From this study, it is proven that the vertical gusset plate is a good alternative to improve bending and torsional stiffnesses of thin-walled chassis.

Keywords
Vehicle structure, Reinforcement, thin-walled structure

Topic
Lightweight Structure

Link: https://ifory.id/abstract/KTLbEvq92JfA