Time filter

Source Type

Gupta P.K.D.,Proof and Experimental Establishment | Pattnaik S.,Fakir Mohan University | Nayak M.,Siksha O' Anusandhan University
Defence Science Journal | Year: 2014

Static images of colour clouds play an important role to predict weather conditions to schedule proof and trial activities, and deploying resources at firing locations and observation posts. In this paper, a new inter-level cloud compression architecture and algorithm has been presented. Distributed architecture suitable for cloud computing has been suggested to implement inter-level compression algorithm (ILCA). Different possibilities between two successive cloud images have been combined to save the images of interest for further processing, ignoring the redundant ones. Vector quantisation technique is briefly discussed to achieve high level of compression. The algorithm presented in this paper can be easily modified to store flying, floating, and moving objects in air, water, and surface, respectively with high level of compression in various defence applications. © 2014, DESIDOC.

Ray K.,Proof and Experimental Establishment
Defence Science Journal | Year: 2010

For test and evaluation of a proximity fuze, it is necessary to know the distance offset of the exploding ammunition round, fitted with the fuze, from a specific target. If the event is recorded using in-line high-speed photography the event of explosion can be resolved in time, and it becomes necessary to ascertain the position of the round, wrt the target, as it is exploding. An estimation of intensity centroid position fails as the flash is non-uniform in nature and is partially occluded by the exploding round. This paper is about an approach to find the location of the round using 2-D shapes fitting of the explosion patch. © 2010, DESIDOC.

Ray K.,Proof and Experimental Establishment
Pattern Recognition | Year: 2013

Edge detection is one of the oldest image processing areas that are still active. An important current area of study involves development of unsupervised edge detection algorithms. In this work a paradigm of unsupervised edge detection is proposed that is based on the computational edge detection approach introduced by Canny. It is a simple and computationally cheap technique that achieves non-trivial results. Additionally as a byproduct it generates information about the content and severity of noise in the image. The proposed technique uses a fast edge detector to generate the initial edge mask and subsequently optimizes that by studying the behavior of a proposed details estimator. The study of the same estimator also offers insight about the noise characteristics of the image. © 2013 Elsevier Ltd.

Biswal T.K.,Proof and Experimental Establishment | Sarkar S.,Proof and Experimental Establishment | Adhikary M.,iversity
Propellants, Explosives, Pyrotechnics | Year: 2013

Measurements of consistency and accuracy are standard techniques to assess the performance of a weapon in case of direct fire kill mechanism. It is often determined from the scoring pattern of a witnessing target erected at a known distance in an open range making use of an in-line CCD camera with suitable long-range optics or using an array of acoustic/optical sensors in the close vicinity of the target. In the case of indoor range, acoustic and optical sensors are used to determine the same preferably for small-caliber ammunitions. However, all these indirect methods are subjected to the constraint of triangulation error. In case of high-caliber ammunitions, especially fired from tank guns, witnessing targets and acoustics methods are used although it is time-consuming and labor-intensive in nature. To overcome these difficulties a virtual scoring method is proposed. Herein, a high-speed video camera is used for in-line image acquisition of the projectile at the desired distance using long-range optics. The virtual target is defined making use of an optical detector placed at the target distance and under the trajectory, where a trigger is generated when the projectile passes over it. This hardware trigger is sent to the high-speed video camera and then the spatial coordinates of the projectile in the virtual plane is determined off-line making use of necessary image processing and image analysis. A feasibility study of this technique was performed in a scaled-down model and laid down in greater details. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sahoo S.,Proof and Experimental Establishment | Laha M.K.,Indian Institute of Technology Kharagpur
Defence Science Journal | Year: 2014

In the present study, the drag variation and trajectory elements estimation of a supersonic projectile having two different nose shapes are made numerically. The study aims at finding the coefficient of drag and shock wave pattern for 130 mm artillery shell fitted with recovery plug or with fuze, when travelling at zero angle of attack in a supersonic flow of air. The coefficient of drag (CD) obtained from the simulation is used as an input parameter for estimation of trajectory elements. The numerical results, i.e., the coefficient of drag at different Mach numbers and trajectory elements are validated with the data recorded by tracking radar from an experimental firing. Based on numerical results and data recorded in experimental firing, the coefficient of drag in the case of the shell with recovery plug is 2.7 times more than for the shell with fuze. The shock wave in the case of the shell with recovery plug is detached bow shock wave, whereas in the case of a shell with fuze, the shock is attached. The results indicate that the coefficient of drag increases with detached shock wave and an increase in the radius of the shell nose. Good agreements were observed between numerical results and experimental observations. © 2014, DESIDOC.

Discover hidden collaborations