Modeling the behavior of high-speed objects in flight

Specialised Imaging Ltd. has reported enthusiastic feedback from customers using its Trajectory Tracker video tracking system to precisely correlate high-speed video data with 3D visualisation and measurement information.

Claude Berner, a Defense Scientist at the French-German Research Institute (ISL) Ballistics Range commented ‘ The SI Trajectory Tracker has proven itself to be a very useful tool and is now systematically deployed for all outdoor tests at our open range test site, especially for the observation of the sabot separation, the behavior of the model in flight as well as its impact at the target’. ‘We have found using the Trajectory Tracker that preliminary quantitative information like spin rate and angles of attack can also be deduced from the videos and compared with the onboard recorded data. He added ‘The recent development of the new in-flight correction mode has tremendously improved the possibilities of tracking models with unpredictable flight characteristics such as for example Earth re-entry space vehicles that exhibit unusual velocity profiles over the flown distance’. ‘Models are now well centered on the camera and no repeat of the shots is necessary anymore’.

Traditionally, faced with charcterising the trajectory of unpredictable high speed objects in flight, engineers have used expensive Doppler radar equipment with sophisticated software, and on-board telemetry. While this methodology has provided useful analytical data it has not allowed visualisation of the processes. The ability to correlate both analytical and visual data over a significant part of an object’s flight, using the SI Trajectory Tracker, offers engineers a valuable new high-speed imaging tool.

Using a pair of Trajectory Tracker systems, with proprietrary flight prediction software and high-speed video cameras - engineers are now able to capture a sequence of images along an objects flight path and also obtain accurate 3D measurements from those sequences. The Trajectory Tracker, with its flight prediction software, is used to accurately track the object along a large portion of the flight path. This allows a very tight field of view which results in higher accuracy for the 3D analysis. The 3D analysis software, from Image Systems AB, allows for the calibration of the system and relating this to the image data streams from the high-speed video camera, produces simultaneous correlated video & measurement data.

The Trajectory Tracker is a next generation video tracking system offering high performance and ease of deployment on a sturdy, fully adjustable mount. The system provides consistent and accurate tracking of objects in flight using a computer controlled triggered rotating mirror positioned in front of a high-speed digital video camera. In order to fully evaluate failure modes of high-speed objects, it is often necessary to observe their performance over a significant proportion of the trajectory. The Trajectory Tracker allows observations to be made of in flight behaviour of high-speed objects over more than 100 metres with a tracking accuracy of better than 0.2 degrees over its full scan. The resulting slow motion record of an object in flight allows accurate diagnosis of events such as fin deployment, motor burn time, pitch, yaw and spin rate.

Specialised Imaging Ltd. is a knowledgeable, dynamic company focused upon design, manufacture, service and supply of ultra high-speed imaging systems and components for industrial, military and scientific applications.

For further information on using the Trajectory Tracker for modeling the behavior of high speed objects in flight please contact Specialised Imaging Ltd on telephone +44 (0) 1442 827 728 or email