High-speed Motion Picture Camera Research Articles

Breaker Contact Movement State Recognition Based on Image Processing

This paper briefly describes a new method of breaker contact movement state recognition. This method is based on image target tracking. Particle filter algorithm can solve the non-linear processing problem, so it is better robustness and accuracy to the image target tracking. Using high-speed motion picture camera to obtain the circuit breaker image can solve some difficulties which are done by traditional ‘contact’ measurement methods. Experimental results show that breaker contact movement state recognition based on image processing is very effective.

Study of the Reynolds Number Effect on the Process of Instability Transition Into the Turbulent Stage.

The results of the experimental study of the Reynolds number effect on the process of the Rayleigh-Taylor (R-T) instability transition into the turbulent stage are presented. The experimental liquid layer was accelerated by compressed gas. Solid particles were scattered on the layer free surface to specify the initial perturbations in some experiments. The process was recorded with the use of a high-speed motion picture camera. The following results were obtained in experiments: (1) Long-wave perturbation is developed at the interface at the Reynolds numbers Re < 104. If such perturbation growth is limited by a hard wall, the jet directed in gas is developed. If there is no such limitation, this perturbation is resolved into the short-wave ones with time, and their growth results in gas-liquid mixing. (2) Short-wave perturbations specified at the interface significantly reduce the Reynolds number Re for instability to pass into the turbulent mixing stage.

화살의 이동궤적을 위한 하드웨어 구성 및 패러독스 측정

The point of impact, the shot group, and the flight traces depend on the combination of unique features which decide moving traces of the arrow (paradox of the archer, length of the arrow shaft, weight, angle of the feather, and spline of the arrow shaft). The more dense the impact points in the shot group and the earlier elimination of paradox of the archer, the higher assessment is given for the product. However, there is no way to objectively assess the efficiency and quality of the arrow, and there is no numeric data to be used as the basis for comparison with other products. Although capturing the images of flying arrow using a high-speed motion picture camera is possible, we are limited to observation from specific view angle only. Hence, the criteria for efficiency and quality assessment are mostly based on subjective opinions of experts or hunters, or review on consumers' remarks. In this paper, we propose a hardware composition that are based on three detection frames consisting of line lasers and photo diode arrays without the high-speed motion picture camera. Predicated on measured coordinates data, a nobel method for the archer's paradox measurement, a key parameter that determine the arrow's trajectory, and corresponding numerical analysis model is proposed.

High Speed Motion Picture Camera for Recording Ink Jet and Recorded Pictures

High Speed Motion Picture Camera for Recording Ink Jet and Recorded Pictures

입체적인 쇼트를 통한 코믹연출연구

When making a comic film, the comic presentation that uses stress and exaggeration is the important subject among other things. In this study we tried to investigate the comic effect using the movement of three-dimensional shot. To conduct this study, we extracted the shot manufactured through the Flow Motion of a 3D Production Program Virtual Camera and a High Speed Motion Picture Camera. The shot manufactured applying this manufacturing skill and using three-dimensional production method for the video contents efficiently made was classified into several scenes. The focus of this study is to search for the factor that makes the atmosphere of a story comic through three-dimensional production shot. According to the shot analysis, three-dimensional production method plays a role in developing more stories on space and time by visualizing stories in three dimensions, which makes the most use of the movement of camera, lens and the utilization of focus. In addition, in the presentation where many comic and exaggerated factors are provided, we used the technology that stresses a scene using the size of a shot and the lasting time and presented the method that exaggerates space using a 3D Production Program Virtual Camera and a High Speed Motion Picture Camera. By reviewing the qualitative improvement and the efficient method on making comic films through the possibility that the atmosphere of this three-dimensional shot can apply to the effect for comic presentation, we tried to approach the comic presentation.

Formation, Oscillation and Deflection of Liquid Film on a Ring Frame

Image of a liquid film forming on a ring frame attached to a DuNoüy surface tensiometer was photographed with a high-speed motion picture camera. Pure water and an aqueous solution with a surfactant were used as the liquids. The formation process and the oscillation of the film were continuously recorded. Observation of the oscillations enabled us to estimate gravitational deflection of the film and the value of the surface tension.

How puffers (Teleostei: Tetraodontidae) swim

Two species of marine Indo-Pacific puffers, Arothron meleagris and A. nigropunctatus, were filmed with a high-speed motion picture camera while swimming in a Brett-type water tunnel at speeds of 1-3.5 body lengths (BL) s−1. The puffers generated thrust by use of their pectoral fins in addition to their dorsal and anal fins; the long axis of the body tilted, mouth upwards, by 3–10) while the fishes swam; antero-ventral body profiles of the fishes changed as swimming speeds increased; pectoral fins undulated and moved 180) out of phase from each other, while dorsal and anal fins oscillated in phase with each other; frequencies of fin movements (F) increased linearly in relation to swimming speeds (Uc(rel)) and were described by the equation F=1.48 Uc(rel)+1.66; stride lengths also increased at higher Uc(rel); and, at swimming speeds above 3.0 BL s−1 puffers began to move their tails in sub carangiform-like modes of burst swimming. These results modify significantly the accepted view of the tetraodonti form mode of median and paired fin swimming.

The combustive sound source; basic principles

The combustive sound source (CSS) is a low-frequency underwater sound source that has appeared in several U.S. patents dating back to 1924, but until now, has not undergone extensive study. Combustible gases are introduced into a combustion chamber and ignited with a spark. The ensuing combustion produces a bubble of expanding gas which, in turn produces high-intensity, low-frequency acoustic pulses. It was observed that low-energy combustions produce several bubble pulses, while high-energy combustions produce a high-pressure first bubble pulse, and fewer, lower amplitude bubble pulses. The boundary between the two regimes was observed at 8900 j, for stoichiometric methane-oxygen (which corresponds to a volume of 0.75 liters at STP), ignited in an open-bottomed conical combustion chamber. A high-speed motion picture camera was used to observe the bubble produced at the boundary condition and pressure signatures were recorded. Behavior from both regimes was observed. For the high-energy case, the bubble motion observed on film is correlated with the measured pressure signature. For the low-energy case, bubble periods observed on film are compared to acoustically measured bubble periods. [Work supported by ONR.]

Regression and combustion characteristics of boron containing fuels for solid fuel ramjets

A windowed, two-dimensional solid-fuel-ramjet motor was used with high-speed motion picture cameras to study the effects of fuel composition, pressure, and air mass flux on the surface behavior of metallized fuels within both the recirculation and boundary-layer combustion regions. Surface behavior and near-surface combustion characteristics were examined to help explain the regression rate/performance characteristics observed in actual motor hardware. Fuels containing no combustion catalyst exhibited the characteristic of extending the combustion envelope to lower pressures with lower values of Shore A hardness. Ignition/flammability limits appeared to be a strong function of surface pyrolysis within the recirculation region. Most metallized fuels exhibited shedding of flakes of (unburned) material from the fuel surface. Flake thickness for boron fuels was typically 200 /*, independent of pressure, and surface areas varied from less than 1 mm2 to approximately 22 mm2. The mass losses attributable to the flaking process play a major role in the overall fuel mass loss mechanism. Bimetallic fuels and fuels containing a combustion catalyst apparently had surface reactions which increase the surface temperature. This should be beneficial for obtaining more complete combustion of the metals within the motor.

High Speed Motion Picture photography for studying the trajectory parameters of .303 Ball MK 7 bullets fired through country-made weapons

Using a 16 HD NAC High Speed Motion Picture Camera in conjunction with a 160B Motion Picture Analyser, the motion of .303, Ball, MK 7 bullets discharged through country-made firearms has been analysed. The data have been used to approximate the trajectory elements of the bullets. It is suggested that the scheme of high speed analysis outlined can be advantageously used in actual cases to generate demonstrative evidence for substantiating the atypical behaviour of such firearms with special reference to their terminal and wound ballistics effects.

Disruptive Burning of Aluminum/arbon Slurry Droplets

Abstract Abstract–The disruptive combustion of probe-supported and free-falling Al/C/JP-lO slurry droplets (200 to 1OOO, μm in diameter) was investigated experimentally. The disruption processes and disruption times were analyzed using backlit or natural-light film records taken with a high-speed motion picture camera. Parametric studies were conducted to investigate the influence of the relative proportions of aluminum and carbon in the solids and of surfactant and stabilizing additive levels; and disruption times were quantified with respect to droplet diameter, total solids loading. ambient gas temperature, and oxygen mole fraction. Slurry composition parameters were found to affect the type and strength of the observed disruptive phenomena presumably by altering the porosity and plasticity of the surface shells of solids formed during the early stages of gasification.

Vaporization behavior of a single droplet impinging on a heated surface with a flame-sprayed ceramic coating. Effect of surface roughness.

An experimental study concerned with the effect of surface roughness of a ceramic-coated surface on droplet vaporization was performed. Test surfaces used were almost identical in surface structure except for the surface roughness. Lifetime curves for several combinations of pure liquid and the hot surface with coating having different roughnesses were measured at surface temperatures up to 1 100 k by a high-speed video optical system. we also observed in detail the vaporization behavior using a 16 mm high-speed motion-picture camera, especially in the rapid vaporization region. The result showed that the higher the surface roughness was, the wider the temperature range yielding the short lifetimes became. In this temperature range, slightly reduced lifetimes caused by the surface roughness were obtained in some cases.

Vaporization behavior of a single droplet impinging on a heated surface with flame-sprayed ceramic coating.

The vaporization behavior of a single droplet impinging on a heated surface which was coated with ceramics such as alumina, magnesium zirconate and zirconium oxide was studied. This is the extension of the previous study on a vaporizing droplet on a solid surface of ceramics. The lifetime curves for some pure liquids were measured at a surface temperature up to 1100 K. We observed in detail the vaporization process of a droplet using a 16 mm high-speed motion-picture camera and high-speed video camera. It should be stressed that the ceramic-coated surface brought a wide temperature range yielding minimum vaporization times and short lifetimes in spite of its thinly coated layer, owing to its low-thermal conductivity and characteristic surface.

An Inverse Dynamic Analysis of the Pole Vault

An inverse analysis of the pole vault was completed using a nine-segment rigid-body model of the vaulter in two dimensions. Competitive vaults by five elite vaulters were recorded on film using a high-speed 16-mm motion picture camera. The films were digitized and the digitized data were smoothed. The resultant joint moment histories at the shoulder, left hip, left knee, right hip, and right knee were computed for each vaulter. The moments produced about the top hand by the lower hand on the pole were also computed. The resultant joint moments at each joint were compared between vaulters and related to observed vault techniques. The moment produced by the lower hand on the pole and the resultant shoulder moment showed the most variance between vaulters. The pole moment indicated that the lower arm pulled on the pole throughout much of the vault. The resultant shoulder joint moment indicated the need for strength in the shoulder joint extensor muscles. Variations in the resultant moments at the lower extremity joints were small despite large apparent differences in the observed kinematics between vaulters.

Erratum to : High Speed Motion Picture Camera for Recording Ink Jet and Recorded Pictures

Erratum to : High Speed Motion Picture Camera for Recording Ink Jet and Recorded Pictures

High-Speed Motion Picture Camera Experiments of Cavitation in Dynamically Loaded Journal Bearings

It is important to know when and where cavitation occurs in bearings because cavitation has an effect on both the power loss and stability of the bearing. A bearing without cavitation can very well be unstable (vibrating) for the same working conditions where a cavitating bearing is stable. A high-speed camera was used to investigate cavitation in dynamically loaded journal bearings. The length-diameter ratio of the bearing, the speeds of the shaft and bearing, the surface material of the shaft, and the static and dynamic eccentricity of the bearing were varied. The results reveal not only the appearance of gas cavitation, but also the development of previously unsuspected vapor cavitation. Analysis is given to support the experimental findings for both gas and vapor cavitation.

Simulation of modified human airborne movements

A method has been developed to permit the analysis of a real-life motion and subsequent simulation of a modified motion. In the method an airborne activity is filmed with two high-speed motion-picture cameras. The films are subsequently analysed to calculate time-dependent three-dimensional coordinates of 21 body landmarks. From the coordinates a series of parameters of the filmed trial are computed. Subsequently, perturbations are introduced into the parameters defining the initial conditions of the airborne motion and/or the patterns of motion of the segments relative to the upper trunk. The resultant modified motion of the multi-segment body model is then generated by computer simulation. The period of validity of the simulated motion was estimated at approximately 0.6–0.8 sec, although this figure could vary for different activities or subjects.

Mechanism of sound production and air recycling in delphinids: Cineradiographic evidence

Soft tissue silicone-casting techniques, spot-film radiography and cineradiography were combined to examine the in situ anatomy and movement of the upper airway structures in live-phonating and dead delphinid porpoises. Three species, Tursiops truncatus, Tursiops gilli, and Stenella longirostris were studied under high-speed x-ray motion picture cameras to observe the movements in the laryngeal and nasal regions associated with sound production. Accurate reconstructions of the nasal sac anatomy were made by associating castings of silicone rubber, with various x-ray photographs using radiocontrast materials. Sounds produced during the video recordings were simultaneously recorded through a contact piezoelectric hydrophone and stored on magnetic tape. Movement of the left nasal plug was found to be precisely associated with internal whistle production, and the right nasal plug was speculated to be the source of internal click production. Externally produced sounds were generated at the blowhole and the air supply control mechanism was found to be the same for all three types of phonation. The nasopharyngeal air space in the anteroventral portions of the skull and in the bony nares controlled the outward movement of air into the upper passages. The nasopharyngeal muscular ’’pump’’ also functioned in withdrawing spent air back down from the upper passages.

Interaction of a surface wave with a crack in a concave half space

The interaction of a Rayleigh wave with a stationary crack in a rectilinear surface was treated in [1, 2]. It was shown that under certain conditions a surface wave can generate dynamic stresses large enough to extend a crack. However, there have been no studies of the interaction of a surface wave with a crack in a curvilinear half space, although this case is encountered more frequently in practice. We use the method of dynamic photoelasticity to observe the interaction of a surface wave with an edge crack along and normal to a concave half space. The research was performed on 350×400×15-mm samples of polymethyl methacrylate. A surface wave of duration up to 50μsec was excited by a point micro explosion on the linear portion of the sample joined with the curvilinear part. The interaction of the surface wave with a crack was recorded in circularly polarized light by an SFR-1 high-speed motion-picture camera at 1.5 · 106 frames/sec.

Helium Bubble Survey of a Parachute-Opening Flowfield Using Computer Graphics Techniques

Neutrally buoyant helium-filled soap bubbles were used to determine fluid particle pathlines and velocities in the airstream surrounding an 18-in. nominal diameter flat circular parachute model. The bubbles, dynamically indistinguishable from the air that they displaced and highly reflective because of their soap film outer surface, were photographed in two orthogonal planes by high-speed motion picture cameras. Positions of matched bubble pairs from the two views were entered into computer files frame by frame by projecting the films onto a digitizing tablet and using a light pen. This information, along with the film frame rates, was used to timedifferentiate the pathlines to produce velocity data. Some 3000 bubble-frame pairs generated velocity plots covering the region near the canopy for times between 7=0 and steady-state conditions.