Abstract: A device comprising a piece of planar substrate embedded with two sensors and two emitters. The substrate has a generally planar surface for application onto the wearer's body part. The emitters and sensors are shown to be arranged in such a way that no subset of any two emitters and one sensor, or subset of any two emitters and one sensor, forms a straight line, which prevents the two sensors from detecting the same noise caused by the same wearer movements.

Abstract: A device comprising a piece of planar substrate embedded with two sensors and two emitters. The substrate has a generally planar surface for application onto the wearer's body part. The emitters and sensors are shown to be arranged in such a way that no subset of any two emitters and one sensor, or subset of any two emitters and one sensor, forms a straight line, which prevents the two sensors from detecting the same noise caused by the same wearer movements.

Abstract: A toy gun that uses air to launch an elongated dart having a rear bore. The toy gun barrel defines a chamber adapted to receive the elongated dart. The barrel has an inner surface which forms a restriction proximate to the second end. The restriction reduces a barrel cross-section. The barrel receives an end portion of the elongated dart therein so that the pressurized air initially pressurizes the rear bore of the elongated dart and pressurizes the chamber outside of the elongated dart between a first barrel end and the restriction as the dart is launched.