A sensing device is described that is configured to be launched from an
air vehicle for deployment on the ground. The sensing device includes at
least one sensor, an inertial measurement unit (IMU), at least one flight
control surface, a flight control unit configured to control a position
of the flight control surfaces, and a processing unit. The processing
unit is coupled to the IMU and is configured to receive a desired
trajectory from an external source and, upon launch of the sensing
device, is further configured to determine an error between the desired
trajectory and a current position as determined by the IMU. The
processing unit is also configured to cause the flight control unit to
adjust a position of the flight control surfaces to minimize the error.