Abstract: A two wheeled throwable robot with a pair of motorized wheels mounted on each end of an elongate body and a rearwardly extending tail. The body comprising a chassis with an accessory mounting interface on top side and rearward side. A backpack accessory providing active sensing or environmental effects has an inverted L-shape when viewed from an end and attaches to the rearward side of the elongate body and extends over the topside of the body. The stabilizing tail for the two wheeled robot attaches to a rearward surface of the backpack accessory. The robot and backpack accessory have impact protection means when the robot is thrown. The backpack accessory may be within a zone of protection defined by the maximum deflection of the wheels or may have elastomeric bumpers when the accessory backpack projects out of the zone of protection.

Abstract: An antenna for radio frequency communication, such as for a reader circuit that is configured to be coupled to a coupler of a system for controlling fluid dispensing. The antenna can include a printed circuit board with an aperture and a plurality of windings disposed circumferentially about the aperture. The antenna can also include a U-shaped core having first and second legs coupled by a third leg, the third leg being coupled to the printed circuit board, and the first and second legs extending generally parallel with respect to opposite sides of the printed circuit board over the plurality of windings.