Peter V. Czipott

Using unmanned aerial vehicle-borne magnetic sensors to detect and locate improvised explosive devices and unexploded ordnance

Magnetic sensors configured as a tensor magnetic gradiometer not only detect magnetic targets, but also determine their location and their magnetic moment. Magnetic moment information can be used to characterize and classify objects. Unexploded ordnance (UXO) and thus many types of improvised explosive device (IED) contain steel, and thus can be detected magnetically. Suitable unmanned aerial vehicle (UAV) platforms, both gliders and powered craft, can enable coverage of a search area much more rapidly than surveys using, for instance, total-field magnetometers. We present data from gradiometer passes over different shells using a gradiometer mounted on a moving cart. We also provide detection range and speed estimates for aerial detection by a UAV.

Innovations in weapons detector portal technology

Conventional concealed weapons detection portals, deployed worlwide at airports, governent buildings, courthouses, and other security critical facilities, are challenged by todays need for stringent and effective entry point screening. Modern threats, like exotic lightweight handguns, are becoming increasingly difficult to detect. Conventional portals do little, if anything, to assist security personnel in resolving the true nature of a potential threat. Systems that rely on blind operator intervention for alarm resolution invite too much human error so security is ultimately compromised. These systems do not instill confidence in the operator or the general public and thus do not present the necessary deterrent to those with sinister intent. Increased detection and improved discrimination do not adequately advance the utility of these security tools. High precision alarm object location information presented to the operator will result in the rapid resolution of the potential threat. Providing this information to the person under scrutiny via a static or streaming video image can enable self-divesting of the offending item without the need for security personnel intervention. Robust detection, effective discrimination, and precise object location information will result in superior entry point screening operations.

Scalable tracking algorithms for magnetic sensor arrays

Magnetic sensors are unaffected by rolling terrain, by vegetation and by weather phenomena, so provide a consistent and predictable performance. Most magnetic tracking algorithms work best for a limited span of closest approach distances between the target and any sensor array node and have specific requirements in terms of the relative node placement. Unlike demonstration fields, where the nodes are carefully manually placed, proposed field deployment methods cannot reliably achieve specific spacings. We propose a novel algorithm that is insensitive to variations in spacing, thereby eliminating the limit on closest approach distances, so that the sensor array can locally adapt the algorithm to the array configuration. This local adaptation also enables scalability for whole-array tracking.

Tracking using magnetic gradiometry enables constant radius orbits around minelike targets

Passive magnetic measurements may be used to determine the azimuth, bearing and range to the target in real time using suitable signal processing without illuminating the target. Collision and even close approach must be avoided for classes of targets such as proximity fuzed mines. This paper describes a simple safety algorithm that monitors data from such a tensor magnetometer system and overrides the normal autopilot to ensure a minimum radius is always maintained from all magnetic targets encountered.