Abstract: A virtual image generation system comprises a planar optical waveguide having opposing first and second faces, an in-coupling (IC) element configured for optically coupling a collimated light beam from an image projection assembly into the planar optical waveguide as an in-coupled light beam, a first orthogonal pupil expansion (OPE) element associated with the first face of the planar optical waveguide for splitting the in-coupled light beam into a first set of orthogonal light beamlets, a second orthogonal pupil expansion (OPE) element associated with the second face of the planar optical waveguide for splitting the in-coupled light beam into a second set of orthogonal light beamlets, and an exit pupil expansion (EPE) element associated with the planar optical waveguide for splitting the first and second sets of orthogonal light beamlets into an array of out-coupled light beamlets that exit the planar optical waveguide.

Abstract: A golf club head with a sole having a low stiffness compliance zone, which allows the face to deflect downward upon impact with a golf ball, is disclosed herein. The compliance zone comprises a plurality of through openings that are filled with one or more filler pieces comprising a low modulus material, all of which are located within three inches of a face section measured along a front-to-back axis of the golf club head.

Abstract: A golf club head, preferably a putter head, comprising at least one structural support member is disclosed herein. The structural support member has a smooth, organic-looking aesthetic, with a continuously changing curvature along its spline and at least one surface, and preferably connects one portion of the golf club head to another portion. Where the support member connects to other portions of the golf club head, the surfaces of the member have a curvature that changes smoothly and continuously, lacking any sharp corners. The support member may be part of a lattice structure formed via binder jetting.

Abstract: An electronic transmitter includes: a modulator to phase modulate a carrier signal with a baseband signal using a phase modulation sequence; and an emitter to emit the phase modulated signal. The phase modulated signal has poor autocorrelation, has a corresponding mismatched filter based on the phase modulation sequence, and is configured to demodulate into the baseband signal through poor cross-correlation with the mismatched filter. Sometimes, the transmitter is part of a sensing apparatus, where the emitter emits the phase modulated signal at a target and the emitted signal reflects off the target. The sensing apparatus includes a receiver that has a collector to collect the reflected signal, and a demodulator to demodulate the collected signal into the baseband signal through the poor cross-correlation with the mismatched filter. Sometimes, the transmitter is part of a communication system, where the emitter emits the phase modulated signal to an intended recipient.

Abstract: An electronic transmitter includes: a modulator to phase modulate a carrier signal with a baseband signal using a phase modulation sequence; and an emitter to emit the phase modulated signal. The phase modulated signal has poor autocorrelation, has a corresponding mismatched filter based on the phase modulation sequence, and is configured to demodulate into the baseband signal through poor cross-correlation with the mismatched filter. Sometimes, the transmitter is part of a sensing apparatus, where the emitter emits the phase modulated signal at a target and the emitted signal reflects off the target. The sensing apparatus includes a receiver that has a collector to collect the reflected signal, and a demodulator to demodulate the collected signal into the baseband signal through the poor cross-correlation with the mismatched filter. Sometimes, the transmitter is part of a communication system, where the emitter emits the phase modulated signal to an intended recipient.

Abstract: An electronic transmitter includes: a generator circuit to generate a baseband signal; a modulator circuit to modulate a carrier signal with the baseband signal; an emitter to emit the modulated signal at an intended recipient; and a distortion circuit to apply a final distortion to the baseband signal or the modulated signal. The final distortion is optimized to minimize the ability of unintended recipients to localize the emitter using correlation-based techniques, and to minimize any degradation to the data rate of the emitted signal at the intended recipient. In some cases, the transmitter is part of an electronic communication system that also includes a receiver at the intended recipient. The receiver is aware of the final distortion and includes a collector to collect the emitted signal, and a demodulator circuit to demodulate the collected signal using the final distortion to recover the baseband signal.

Abstract: A rotary aircraft includes a cylindrically tubular hub mounting a plurality of outwardly extending, resiliently flexible blades. The blades are uniformly spaced around the hub and its central axis and fixed in pitch. Outer tips on each of the blades are downwardly turned and outwardly turned sufficiently to balance the lift generated by the blades from air striking the aircraft horizontally when the aircraft is in hover to provide passive stability to the aircraft. A pair of propellered electric motors are mounted on a diametrically opposing pair of the blades, pitched transversely to the central axis of the hub and to a plane perpendicular to the central axis, to simultaneously provide both lift and rotation. A battery supplies all power used by the aircraft while radio control circuitry in the hub permits variation of the power supplied to the motors for altitude control of the aircraft.

Abstract: A sonar system for arctic seafloor reconnaissance has a pair of transducers affixed to a holder so as to form a transducer array. A vertically extended tube assembly rotatably supported by a tripod suspends this transducer array at a specified depth in water such that the transducer array is tilted at a specified tilting angle and oriented in a specified azimuthal direction. One of the transducers is made to emit directional acoustic signals and the reflected acoustic signals received by both of the transducers are converted into electrical signals. These signals are processed together with signals indicative of the tilting angle and the orientation of the transducer array to obtain seafloor imagery and depth data.

Abstract: A flight system capable of passively stable hover comprises an apparatus defining a vertical axis, and including multiple upright ducts spaced about the axis; fluid momentum generators in the ducts to effect flow of fluid downwardly in the ducts; and fluid flow deflector structure in the path of the downwardly flowing fluid, and angled to deflect the fluid flow away from the axis, in such manner as to provide stability in hover of the apparatus.

Abstract: A flight system capable of passively stable hover and horizontal translatory flight, comprises an apparatus defining a vertical axis, and including multiple ducts with substantially vertical axes in hover mode, spaced the axis; fluid momentum generators in the ducts to effect flow of fluid downwardly in the ducts in hover; and fluid flow deflector structure in the path of the flowing duct fluid, and angled to deflect the fluid flow away from the axis, in such manner as to provide stability in hover of the apparatus, as well as stability when the entire device is tilted through approximately 90.degree. to execute horizontal translatory flight.

Abstract: A terrain surveillance, powered aircraft is disclosed to have an on-board video camera that is not gimballed relative to the aircraft, the aircraft typically comprising multiple components; the method of the invention including: assembling the components into aircraft configuration at or near a launch site; launching the aircraft at that site with no human pilot on board same; remotely controlling the flight path of the aircraft by radio or cable link, to fly to a location for terrain surveillance; operating the on-board video camera to survey the terrain while varying yaw of the aircraft to provide sweep viewing of the terrain; and recovering the aircraft by controlling its flight to steeply descend to a landing zone.

Abstract: A machine for compacting in one series of operations up to a truckload of snow removed from city streets and the like. The machine has a hopper for receiving such snow, a compacting chamber and a hydraulically operated blade for compacting snow in the chamber. The compacting chamber is positioned below and to one side of the hopper whereby it is gravity fed. The chamber has opposite, parallel, fixed sides on all but the blade and exit sides. The exit side is completely closed in by a gate. Means are provided to move the blade from a first position below and to the outer side of the hopper to a second position towards the exit gate of the chamber when in compacting action, and from this second position back to first position when in recharge action. Further means are provided to pivot the blade from a transverse, fixed, vertically oriented position when in compacting action to a transverse, fixed, horizontally oriented position when in recharge action.