Spark Shadowgraph Light Source Characterization for Ballistic Range Upgrade

Author(s):

William Aubry, Steven Dean, and Christopher Mermagen

Abstract:

A modernization effort is currently underway to update instrumentation at two spark shadowgraphy ranges at ARL’s Transonic and Aeroballistic Experimental Facilities. This effort entails replacing older analog timers and wet film cameras with digital control and camera systems. The ranges are used to capture and analyze free-flight phenomena for small- and large-caliber, gun-launched projectiles and to develop flight characteristics of projectiles by capturing in-flight position, time, and orientation data from orthogonal-view spark shadowgraph stations. Each station includes at least one camera and spark light source, depending on the facility. To help define requirements for the digital camera upgrades in both ranges, various spark light sources available to the authors were characterized by measuring light intensity and duration, guiding optimal lighting configurations for the upgrades.