scholarly journals Analisa Kekuatan Impak Helmet Sepeda Motor Metode Impak Jatuh Bebas

2017 ◽  
Vol 2 (1) ◽  
pp. 42
Author(s):  
Rahmat Kartolo Simanjuntak
Keyword(s):  
Impact Loading ◽  
Minimum Energy ◽  
Free Fall ◽  
Load Cell ◽  
Impact Testing ◽  
Time Signal ◽  
Research Activity ◽  
Testing Apparatus ◽  
Impact Time ◽  
The Impact

The non-standard helmet testing is required for measure the helmet strength as effect of the load is given. In generally, traffic accident doesn�t involved by the velocity but also gravitational. Therefore, the research activity is done by researcher obtains the effect of free-fall impact loading on the non-standard helmet. The information which is obtained from this research will explain the effect of free-fall impact loading that is subjected on the non-standard helmet to user, industry, and also government. The objective of this research involves the testing apparatus construction of free-fall impact loading on the non-standard helmet, measuring the maximum impact loading, and the energy absorbing by helmet as effect of impact loading. The researcher collaborates with the Impact and Fracture Reaseach Center (IRFC) has bulit the testing apparatus which is equipped with good aquisition data system. The non-standar helmet is put on the adjustable testing rig. The impact time can be measured by eight inductive proximity sensors. The helmet will slide down and collides the anvil. The force will be measured with the load cell which is put down the anvil. There are four anvil forms which is adapted to the real condition, that is: flat plat, aligned plat, bullet, and a half-spherical anvil. The data will be transfered from the load cell into the DAQ system which has function to change the analog into digital signal. Finally, the data will be saved into PC as the force (N) and the impact time (ms). The free-fall impact testing equipment has shown the best performance on the force and impact time signal reading as long as the research activity. The maximum force on the flat anvil is 24.33 N; the aligned flat anvil is 37.88 N; the bullet anvil is 16.22 N; and a half-spherical anvil is 41.43 N at the elevation of 0.75 m. The minimum energy which causes the fracture on the helmet is 3.24 J at the elevation of 0.3 m.

scholarly journals Investigation on the Application of Taylor Impact Test to High-G Loading

2021 ◽  
Vol 8 ◽  
Author(s):  
Li Juncheng ◽  
Chen Gang ◽  
Lu Yonggang ◽  
Huang Fenglei
Keyword(s):  
Pulse Duration ◽  
Impact Loading ◽  
Impact Test ◽  
Impact Load ◽  
Low Cost ◽  
Large Mass ◽  
Impact Testing ◽  
Taylor Impact ◽  
Taylor Impact Test ◽  
The Impact

Taylor impact test is characterized by high impact energy, low cost, and good repeatability, giving it the technical foundation and development potential for application in high-g loading. In this paper, the feasibility of performing high-g load impact testing to a missile-borne recorder by conducting Taylor impact test was studied by combining simulation analyses with experimental verification. Acccording to the actual dimensions of the missile-borne recorder, an experimental piece was designed based on the Taylor impact principle. The impact loading characteristics of the missile-borne recorder were then simulated and analyzed at different impact velocities. In addition, the peak acceleration function and the pulse duration function of the load were fitted to guide the experimental design. A Taylor-Hopkinson impact experiment was also conducted to measure the impact load that was actually experienced by the missile-borne recorder and the results were compared with the results of strain measurements on the Hopkinson incident bar. The results showed that the peak value of impact load, the pulse duration and the waveform of the actual experimental results were in good agreement with the results predicted by the simulations. Additionally, the strain data measured on the incident bar could be used to verify or replace the acceleration testing of the specimen to simplify the experimental process required. Based on the impact velocity, high-g loading impact was achieved with peak values in the 7,000–30,000 g range and durations of 1.3–1 ms, and the waveform generated was a sawtooth wave. The research results provide a new approach for high amplitude and long pulse duration impact loading to large-mass components, and broaden the application field of Taylor impact test.

TESTING METHOD FOR MEASURING IMPACT STRENGTH OF BGA SOLDER JOINTS ON ELECTRONIC PACKAGE

2008 ◽  
Vol 22 (09n11) ◽  
pp. 1050-1055
Author(s):  
TADAHARU ADACHI ◽  
HIROTAKA GOTO ◽  
WAKAKO ARAKI ◽  
TAKAHIRO OMORI ◽  
NORIYASU KAWAMURA ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Impact Strength ◽  
Solder Joints ◽  
Testing Machine ◽  
Load Cell ◽  
Impact Testing ◽  
Circuit Board ◽  
Rear Side ◽  
Electronic Package ◽  
The Impact

A pendulum-impact testing machine was developed to measure the impact strength of ball-grid-array (BGA) solder joints between an electronic package and a circuit board. Ball solders were connected to daisy-chain between a dummy electronic package and a circuit board. The upper side of the package was directly bonded to a load cell. The rear side of the circuit board was also bonded to an aluminum alloy block fixed on a base. A pendulum made of aluminum alloy was collided into the load cell to apply tensile impact to the solder joints through the load cell. The history of the impact load could be controlled by raising the angle of the pendulum. The fracture of a BGA solder joint was detected by measuring the resistance of the daisy-chain circuit on the board. Therefore, the impact strengths of the solder joints at electrical disconnection and mechanical breaking of all joints could be determined. The experimental results showed that this method is useful for measuring the impact strength of BGA solder joints.

Analysis of Impact Fracture Behavior in Bulk Amorphous Metals Using Instrumented Impact Testing Apparatus

2006 ◽  
Vol 326-328 ◽  
pp. 1665-1668
Author(s):  
Hyung Seop Shin ◽  
Ki Hyun Kim
Keyword(s):  
Shear Bands ◽  
Impact Testing ◽  
Impact Fracture ◽  
Amorphous Metals ◽  
Displacement Curve ◽  
Testing Apparatus ◽  
Impact Fracture Behavior ◽  
Fracture Behaviors ◽  
Impact Tester ◽  
The Impact

In order to investigate the mechanical behavior of newly developed materials such as bulk amorphous metals, it is essential to use small-size specimens. An instrumented impact testing apparatus was devised which could provide a load-displacement curve on subsize Charpy specimens under impact loading without oscillations. The impact fracture behaviors of Zr-based bulk amorphous metals (BAM) were investigated by using the instrumented impact tester using both V-notched and precracked subsize Charpy specimens. It was found that most of the fracture energy absorbed was used in the process of crack initiation through the development of shear bands.

Energy-Absorbing Capacity of Polyurethane/SiC/Glass-Epoxy Laminates Under Impact Loading

2017 ◽  
Vol 139 (2) ◽  
Author(s):  
G. Balaganesan ◽  
V. Akshaj Kumar ◽  
V. C. Khan ◽  
S. M. Srinivasan
Keyword(s):  
Energy Absorption ◽  
Impact Loading ◽  
Composite Laminate ◽  
Failure Modes ◽  
Impact Testing ◽  
Low Velocity Impact ◽  
Low Velocity ◽  
Fiber Failure ◽  
The Impact ◽  
Layered Target

This paper presents the energy absorption of target materials with combinations of polyurethane (PU) foam, PU sheet, SiC inserts, and SiC plate bonded to glass fiber reinforced composite laminate backing during impact loading. SiC inserts and SiC plates are bonded as front layer to enhance energy absorption and to protect composite laminate. The composite laminates are prepared by hand lay-up process and other layers are bonded by using epoxy. Low-velocity impact is conducted by using drop mass setup, and mild steel spherical nosed impactor is used for impact testing of target in fixed boundary conditions. Energy absorption and damage are compared to the target plates when subjected to impact at different energy levels. The energy absorbed in various failure modes is analyzed for various layers of target. Failure in the case of SiC inserts is local, and the insert under the impact point is damaged. However, in the other cases, the SiC plate is damaged along with fiber failure and delamination on the composite backing laminate. It is observed that the energy absorbed by SiC plate layered target is higher than SiC inserts layered target.

scholarly journals Desain Alat Uji Impak Jatuh Bebas Untuk Pengujian Baja Struktur

2020 ◽  
Vol 1 (2) ◽  
pp. 29-37
Author(s):  
Dailami Dailami ◽  
Samsul Bahri ◽  
Hamdani Hamdani
Keyword(s):  
Structural Steel ◽  
Impact Test ◽  
Steel Structure ◽  
Steel Structures ◽  
Free Fall ◽  
Operating Conditions ◽  
Impact Testing ◽  
Test Tool ◽  
Price Momentum ◽  
The Impact

Abstract Impact testing is a test to measure material resistance to shock loads (dynamic). Impact testing simulates the material operating conditions often encountered when the load does not always occur slowly but rather comes suddenly. The impact test equipment to be designed in this study is a free-fall impact test. This impact test tool utilizes the mass of the object and the force of gravity. This test aims to analyze the effect of free fall impact loading on steel structures dropped from 1.5m height. The steps taken in this study include testing and data collection to determine the energy absorbed, the impact price, momentum, impulse and toughness in steel structure material when given a shock load. In this free fall impact test, weight load is at (m) = 2.4 kg with an altitude distance of (h) = 1.5m. The test results showed that the maximum absorbable energy of structural steel is at (E) = 352.94 J, the maximum impact value of structural steel at (HI) = 8.82 J / mm2, the maximum momentum of structural steel at (M) 39.04 kg.m / s and the maximum implant steel structure at (I) 39.04 Ns. Mechanical behaviour is indicated by the bending of the specimen due to impact collision (striker) when testing is done. Keywords: Free-fall impact, Structure steel __________________________ Abstrak Pengujian impak merupakan suatu pengujian untuk mengukur ketahanan bahan terhadap beban kejut (dinamis). Pengujian impak mensimulasikan kondisi operasi material yang sering ditemui dimana beban tidak selamanya terjadi secara perlahan-lahan melainkan datang secara tiba-tiba. Alat uji impak yang akan dirancang dalam penelitian ini merupakan alat uji impak jatuh bebas. Alat uji impak ini memanfaatkan massa benda serta gaya gravitasi. Pengujian ini bertujuan untuk menganalisa pengaruh pembebanan impak jatuh bebas pada baja struktur yang dijatuhkan dari ke tinggian 1,5m. Langkah yang dilakukan dalam penelitian ini meliputi pengujian dan pengambilan data untuk mengetahui energi yang diserap, harga impak, momentum, implus dan ketangguhan pada material baja struktur saat diberi beban kejut. Pada pengujian impak jatuh bebas ini, mempunyai jarak dan berat beban yaitu pada beban (m) = 2,4 kg dengan jarak ketinggian (h) = 1,5m . Dari hasil pengujian yang diperoleh energi yang diserap maksimum baja struktur (E) = 352,94 J, harga impak maksimum baja struktur (HI) = 8,82 J/mm2, momentum maksimum baja struktur (M) 39,04 kg.m/s dan implus maksimum baja struktur (I) 39,04 Ns. Perilaku mekanis ditunjukkan dengan terjadinya pembengkokan pada spesimen akibat benturan Beban (striker) saat pengujian dilakukan. Kata Kunci: Impak jatuh bebas, Baja struktur __________________________

The Development of a Substitute Bird Model

1981 ◽  
Vol 103 (4) ◽  
pp. 725-730 ◽  
Author(s):  
James S. Wilbeck ◽  
James L. Rand
Keyword(s):  
Impact Loading ◽  
Impact Testing ◽  
Hydrodynamic Theory ◽  
Impact Event ◽  
Loading History ◽  
Comprehensive Program ◽  
Engine Blade ◽  
History Of ◽  
The Impact

A comprehensive program was conducted to develop a model synthetic bird for use in engine blade impact testing. A hydrodynamic theory of the impact event was used to aid in determining the bird properties which had to be duplicated in the model. Of the two candidate models studied extensively, it was determined that a projectile fabricated from commercial gelatin impregnated with phenolic mircoballoons most nearly duplicated the impact loading history of real birds.

The Response of the Seated Human to Sinusoidal Vibration and Impact

1987 ◽  
Vol 109 (4) ◽  
pp. 279-284 ◽  
Author(s):  
M. H. Pope ◽  
D. G. Wilder ◽  
L. Jorneus ◽  
H. Broman ◽  
M. Svensson ◽  
...  
Keyword(s):  
Transfer Functions ◽  
Impact Testing ◽  
Test Method ◽  
Sign Test ◽  
Low Back ◽  
Sinusoidal Vibration ◽  
Testing Apparatus ◽  
Seated Posture ◽  
The Impact ◽  
Insight Into

Low back pain has been shown to occur more frequently among vehicle drivers than in representative control groups. Thus the response of the human to vibration and impact is of interest. This study investigated the response of the spine to both impact and sinusoidal excitation in either a relaxed or erect seated posture. The sinusoidal testing apparatus used was a resonating system consisting of two parallel wooden beams, simply supported, and the impact testing apparatus a bearing-guided, spring-suspended platform, struck from below. Ten subjects (5 males, 5 females) were evaluated using both methods. Transfer functions were compared at 2–4 Hz, 4–8 Hz and 8–16 Hz intervals using a sign test. Although in 24 comparisons of either test method (vibration or impact) or posture (erect or relaxed) where eleven showed differences significant at the p < .05 level, only 2 out of 24 comparisons were the differences distinct enough to be significant (at the p < .01 level). Both of these latter differences were due to test method while the subjects were sitting erect. In those instances where there were no significant differences due to test method, the impact method may be a viable replacement for the vibration test method. Where the levels of significance are higher (p < .01 or p < .05), further study of the magnitude of the differences is indicated and may reveal further insight into the seated individual as a system.

Prediction of Energy Absorption Capability of Curved Panel Structure; For Wing Leading Edge Study

2012 ◽  
Vol 225 ◽  
pp. 178-182
Author(s):  
Nurihan Omar ◽  
Nur Aisyah Md Khalid ◽  
Nor Fadilah Shamsudin ◽  
Yulfian Aminanda
Keyword(s):  
Energy Absorption ◽  
Impact Loading ◽  
Leading Edge ◽  
Impact Testing ◽  
Experimental Results ◽  
Radius Of Curvature ◽  
Element Analysis ◽  
Edge Structure ◽  
Curved Panel ◽  
The Impact

This paper works on the curvature effect of wing leading edge structure subjected to impact loading. At first stage, rigid spherical projectile and semi-elliptical panel were used. The impact testing has been carried out by varying the radius of curvature and the thickness of the panel. The experimental results show the trend of specific energy absorption capability of structure in function of the radius and thickness of panel. From experimental observation, it shows that the failure of structure subjected to impact loading can be distinguished in two types of failure; the projectile went through the structure and large displacement of curved panel. The two failure criteria are used later on to determine the energy absorption capability using Finite Element Analysis method. A FEA model is proposed to simulate the behavior of curved composite structure and validated by the experimental results in order, as final goal, to propose the simulation as a tool of designing the leading edge of wing with an optimum radius curvature and thickness of wing leading edge panel to absorb a specific magnitude of impact energy.

scholarly journals Impact Testing of 3D Re-Entrant Honeycomb Polyamide Structure Using Split Hopkinson Pressure Bar

2021 ◽  
Vol 11 (21) ◽  
pp. 9882
Author(s):  
Jiangping Chen ◽  
Weijun Tao ◽  
Shumeng Pang
Keyword(s):  
Energy Absorption ◽  
Impact Velocity ◽  
Impact Loading ◽  
Split Hopkinson Pressure Bar ◽  
Impact Testing ◽  
Hopkinson Pressure Bar ◽  
Static Test ◽  
Split Hopkinson ◽  
Pressure Bar ◽  
The Impact

In this study, a total of 30 3D re-entrant honeycomb specimens made of polyamide were fabricated with various configurations by using the additive manufacturing (AM) technique. Split Hopkinson Pressure Bar (SHPB) tests were conducted on the RH specimens at different impact velocities. The incident, reflected and transmitted waveforms can well explain the wave propagation and energy absorption characteristics of the specimens, which can help us to understand and analyse the process of impact loading. The stress–strain curves, energy absorption ability and failure modes of SHPB tests with different impact velocities and quasi-static compression tests were analysed and compared, and it was found that the flow stress and energy absorption ability of the specimens subjected to impact load were much improved. Among the tested specimens, specimen C2, with a smaller re-entrant angle θ, displayed the best energy absorption ability, which was 1.701 J/cm3 at the impact velocity of 22 m/s and was 5.1 times that in the quasi-static test. Specimen C5 had the longest horizontal length of the diagonal bar L0, and its energy absorption was 1.222 J/cm3 at the impact velocity of 22 m/s and was 15.7 times that in the quasi-static test, reflecting the superiority of a structurally stable specimen in energy absorption under impact loading. The test results can provide a reference for the optimization of the design of the same or similar structures.

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