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We discuss the development of Position-Adaptive Sensors [1] for purposes for detecting embedded chemical substances
in challenging environments. This concept is a generalization of patented Position-Adaptive Radar Concepts developed
at AFRL for challenging conditions such as urban environments. For purposes of investigating the detection of
chemical substances using multiple MAV (Micro-UAV) platforms, we have designed and implemented an experimental
testbed with sample structures such as wooden carts that contain controlled leakage points. Under this general concept,
some of the members of a MAV swarm can serve as external position-adaptive "transmitters" by blowing air over the
cart and some of the members of a MAV swarm can serve as external position-adaptive "receivers" that are equipped
with chemical or biological (chem/bio) sensors that function as "electronic noses". The objective can be defined as
improving the particle count of chem/bio concentrations that impinge on a MAV-based position-adaptive sensor that
surrounds a chemical repository, such as a cart, via the development of intelligent position-adaptive control algorithms.
The overall effect is to improve the detection and false-alarm statistics of the overall system.
Within the major sections of this paper, we discuss a number of different aspects of developing our initial MAV-Based
Sensor Testbed. This testbed includes blowers to simulate position-adaptive excitations and a MAV from Draganfly
Innovations Inc. with stable design modifications to accommodate our chem/bio sensor boom design. We include details
with respect to several critical phases of the development effort including development of the wireless sensor network
and experimental apparatus, development of the stable sensor boom for the MAV, integration of chem/bio sensors and
sensor node onto the MAV and boom, development of position-adaptive control algorithms and initial tests at IDCAST
(Institute for the Development and Commercialization of Advanced Sensor Technologies), and autonomous positionadaptive
chem/bio tests and demos in the MAV Lab at AFRL Air Vehicles Directorate. For this particular MAV
implementation of chem/bio sensors, we selected miniature Methane, Nitrogen Dioxide, and Carbon Monoxide sensors.
To safely simulate the behavior of chem/bio substances in our laboratory environment, we used either cigarette smoke
or incense. We present a set of concise parametric results along with visual demonstration of our new position-adaptive
sensor capability. Two types of experiments were conducted: with sensor nodes screening the chemical contaminant
(cigarette smoke or incense) without MAVs, and with a sensor node integrated with the MAV. It was shown that the
MOS-based chemical sensors could be used for chemical leakage detection, as well as for position-adaptive sensors on
air/ground vehicles as sniffers for chemical contaminants.
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