Dynamic Impact Characterization of Al+Fe2O3+30% Epoxy Composites Using Time Synchronized High-Speed Camera and VISAR Measurements

2005 ◽  
Vol 896 ◽  
Author(s):  
Louis Ferranti ◽  
Naresh N. Thadhani
Keyword(s):  
Dynamic Loading ◽  
High Speed ◽  
Elastic Recovery ◽  
Axial Strain ◽  
Epoxy Composites ◽  
Surface Velocity ◽  
High Speed Camera ◽  
Wave Interactions ◽  
Impact Experiments

AbstractReverse Taylor anvil-on-rod impact experiments were conducted on Al+Fe2O3+30% epoxy composites to measure their viscoelastic and fracture response to dynamic loading. Impact velocities ranged from 80 to 200 m/s. High-speed camera images capturing transient deformation reveal these materials exhibit significant elastic recovery in both the longitudinal and radial directions. Images were time synchronized with free surface velocity measurements, using VISAR, to track elastic/plastic wave interactions attributed to the material’s dynamic loading response. Some specimens underwent brittle fracture once a critical areal strain was exceeded while the axial strain response appeared unaltered.

scholarly journals Stability, spatial extension and extinction of an electric arc in aeronautical conditions of pressure under 540 V DC

2019 ◽  
Vol 87 (3) ◽  
pp. 30901
Author(s):  
Romaric Landfried ◽  
Mohamed Boukhlifa ◽  
Thierry Leblanc ◽  
Philippe Teste ◽  
Jonathan Andrea
Keyword(s):  
High Speed ◽  
Electric Arc ◽  
High Speed Camera ◽  
Arc Length ◽  
Electrode Gap ◽  
Arc Current ◽  
The Mean ◽  
The Stability ◽  
Energy Dissipated

This work deals with the characterization of DC electric arcs in aeronautical conditions of pressure (from 104 Pa to 105 Pa). Observations have been made with the help of a high speed camera and various characteristics of electric arc under 540 V DC have been studied: the stability arc length, the extinction gap, the arc duration and the mean energy dissipated in the arc. The arc current intensity range is 10–100 A. The obtained results show that the arc stability length, extinction electrode gap, arc duration and energy dissipation in the arc have a direct correlation with the pressure and the current in the circuit.

Rate Dependent Material Model for Helmet Pads

2020 ◽  
Author(s):  
Timothy G. Zhang ◽  
A. H. Fulton ◽  
K. Ravi-Chandar ◽  
Sikhanda S. Satapathy
Keyword(s):  
Mechanical Properties ◽  
Material Properties ◽  
High Speed ◽  
Material Model ◽  
High Speed Camera ◽  
Low Velocity ◽  
Rate Dependent ◽  
Military Helmet ◽  
The Impact ◽  
Impact Experiments

Abstract Foam pads are commonly used in sports and military helmet for energy absorption, form-fitting and comfort. Both for low velocity and high velocity applications, their rate-dependent mechanical properties need to be characterized to understand their ability to effectively modulate the transmitted stress pulse. Impact experiments were conducted on bilayer helmet pads at a range of velocities covering low to medium rates up to ∼7000/s. Images from high-speed camera were used to construct x-T diagrams to measure the shock speeds from the impact experiments. Numerical simulations were carried out to validate a foam pad model and to understand experimental uncertainties. The scatter in the measured shock speeds was found to be related to the scatter in the material properties.

scholarly journals High-speed camera characterization of voluntary eye blinking kinematics

2013 ◽  
Vol 10 (85) ◽  
pp. 20130227 ◽  
Author(s):  
Kyung-Ah Kwon ◽  
Rebecca J. Shipley ◽  
Mohan Edirisinghe ◽  
Daniel G. Ezra ◽  
Geoff Rose ◽  
...  
Keyword(s):  
Clinical Research ◽  
Healthy Volunteers ◽  
Ocular Surface ◽  
High Speed ◽  
High Potential ◽  
Potential Usefulness ◽  
High Speed Camera ◽  
Master Curves ◽  
Time Data

Blinking is vital to maintain the integrity of the ocular surface and its characteristics such as blink duration and speed can vary significantly, depending on the health of the eyes. The blink is so rapid that special techniques are required to characterize it. In this study, a high-speed camera was used to record and characterize voluntary blinking. The blinking motion of 25 healthy volunteers was recorded at 600 frames per second. Master curves for the palpebral aperture and blinking speed were constructed using palpebral aperture versus time data taken from the high-speed camera recordings, which show that one blink can be divided into four phases; closing, closed, early opening and late opening. Analysis of data from the high-speed camera images was used to calculate the palpebral aperture, peak blinking speed, average blinking speed and duration of voluntary blinking and compare it with data generated by other methods previously used to evaluate voluntary blinking. The advantages of the high-speed camera method over the others are discussed, thereby supporting the high potential usefulness of the method in clinical research.

Characterization of calculus migration during Ho:YAG laser lithotripsy by high speed camera using suspended pendulum method

2014 ◽  
Author(s):  
Jian James Zhang ◽  
Danop Rajabhandharaks ◽  
Jason Rongwei Xuan ◽  
Ray W. J. Chia ◽  
Tom Hasenberg
Keyword(s):  
High Speed ◽  
Laser Lithotripsy ◽  
High Speed Camera ◽  
Ho:Yag Laser

scholarly journals Characterization of a nitrogen gliding arc plasmatron using optical emission spectroscopy and high-speed camera

2018 ◽  
Vol 52 (6) ◽  
pp. 065201 ◽  
Author(s):  
Sven Gröger ◽  
Marleen Ramakers ◽  
Marc Hamme ◽  
Jose A Medrano ◽  
Nikita Bibinov ◽  
...  
Keyword(s):  
Emission Spectroscopy ◽  
High Speed ◽  
Optical Emission Spectroscopy ◽  
Optical Emission ◽  
High Speed Camera ◽  
Gliding Arc

Scalable Detection of Defects in Additively Manufactured PLA Components

2018 ◽  
Author(s):  
Amol Kulkarni ◽  
Amey Vidvans ◽  
Mustafa Rifat ◽  
Gregory Bicknell ◽  
Xi Gong ◽  
...  
Keyword(s):  
High Resolution ◽  
Digital Image Correlation ◽  
Rigid Body ◽  
Digital Image ◽  
High Speed ◽  
Rotation Speed ◽  
Image Correlation ◽  
High Speed Camera ◽  
Body Rotation

The present work delineates a novel and scalable approach to characterization of defects in additively manufactured components. The approach is based on digital image correlation and involves characterization of surface speeds during rigid body rotation of the workpiece, followed by normalization with respect to rotation speed. Towards this, two different imaging sources were tested, viz. smartphone camera and sophisticated high-resolution/high-speed camera. The proposed approach successfully delineated horizontal and vertical notch defects in a simple FDM fabricated component. Accuracy of this approach was tested with concomitant laser based scanning. Some limitations of this approach were discussed.

HYPERVELOCITY IMPACT RESPONSE OF STITCHED CFRP LAMINATES

2021 ◽  
Author(s):  
KHARI HARRISON ◽  
KALYAN RAJ KOTA ◽  
JACOB A. ROGERS ◽  
PAUL T. MEAD ◽  
ANIKET MOTE ◽  
...  
Keyword(s):  
Atmospheric Pressure ◽  
High Speed ◽  
Hypervelocity Impact ◽  
Carbon Fabric ◽  
Cfrp Laminates ◽  
Damage Propagation ◽  
Gas Gun ◽  
Back Face ◽  
Impact Experiments

In this study, hypervelocity impact experiments were performed on both unstitched and through-thickness Vectran™-stitched laminates. Both laminate types were fabricated from DMS-2436 class-72 warp-knit multiaxial carbon fabric, infused with API-1078 resin using a Controlled Atmospheric Pressure Resin Infusion (CAPRI) process. The laminates were impacted by 4 mm diameter, spherical, Nylon 6/6 projectiles at nominal velocities of 4 km/s using a two-stage light gas gun. The primary measures of the performance of the composite at protecting against impact were in plane hole damage areal comparisons and the comparison of the target back-face debris cloud (BFDC) velocities relative to the incoming projectile velocities. Additional post-shot forensics include characterization of damage morphology and analysis of high-speed videos. Initial inferences about the damage produced in the laminate indicate that the Vectran™ stitching can effectively arrest in-plane damage propagation; impacts at or near a stitchline resulted in no damage propagation across the stitchline boundaries.

Characterization of laminar flame using high speed camera and spectrometer

Sadhana ◽  
2020 ◽  
Vol 45 (1) ◽  
Author(s):  
Manasa Ram Kotal ◽  
Somnath De ◽  
Soumyadeep Das ◽  
Swarnendu Sen
Keyword(s):  
High Speed ◽  
Laminar Flame ◽  
High Speed Camera
Sign in / Sign up

Export Citation Format

Share Document