Abstract: Motion control circuitry for a vehicle-borne, gimbal-mounted sensor (such as a camera on a helicopter) includes main position control circuitry generating a commanded drive signal representing a desired driving of a positioning element (e.g. azimuth or elevation motor) to achieve a position of the sensor, and feed-forward vibration cancellation circuitry generating a cancellation drive signal representing a driving of the positioning element to cancel vehicle vibration. The feed-forward vibration cancellation circuitry includes a vibration sensor and adaptive feed-forward control circuitry, the vibration sensor generating a vibration signal representative of the vehicle vibration, and the adaptive feed-forward control circuitry applying a feed-forward gain to the vibration signal to generate the cancellation drive signal.

Abstract: A multi-axis gimbal has each axis defined by a respective spherical shell driven by a flat, compact motor attached to the driven shell and to a next outer shell (or to an external mounting platform, in the case of the outermost shell). The shells rotate about respective axes. In one configuration, the outermost shell is referred to as the “azimuth” shell because in use it rotates about a vertical axis. The next inner shell is an elevation shell that rotates about a first horizontal axis that is orthogonal to the axis of the camera or other sensor payload. An optional third shell can be used to provide “roll” motion, such as rotating a camera about its axis to obtain a particular rotational orientation with respect to a target.

Abstract: A disclosed sensor includes a light emitter configured to transmit an emitted light beam having a range of wavelengths toward a reflecting element that is configured to produce a reflected light beam having a particular wavelength that is a function of an angle of incidence of the emitted light beam from a normal of the reflecting element. The sensor also includes a color sensor in proximity to and fixed relative to the light emitter and configured to (i) receive the reflected light beam, (ii) detect the particular wavelength of the reflected light beam, and (iii) transmit a color signal indicating the particular wavelength of the reflected light beam. The sensor further includes processing circuitry disposed in electrical communication with the color sensor and configured to receive the color signal and calculate the angle of incidence based on the particular wavelength.

Abstract: A multi-axis gimbal has each axis defined by a respective spherical shell driven by a flat, compact motor attached to the driven shell and to a next outer shell (or to an external mounting platform, in the case of the outermost shell). The shells rotate about respective axes. In one configuration, the outermost shell is referred to as the “azimuth” shell because in use it rotates about a vertical axis. The next inner shell is an elevation shell that rotates about a first horizontal axis that is orthogonal to the axis of the camera or other sensor payload. An optional third shell can be used to provide “roll” motion, such as rotating a camera about its axis to obtain a particular rotational orientation with respect to a target.

Abstract: A disclosed sensor includes a light emitter configured to transmit an emitted light beam having a range of wavelengths toward a reflecting element that is configured to produce a reflected light beam having a particular wavelength that is a function of an angle of incidence of the emitted light beam from a normal of the reflecting element. The sensor also includes a color sensor in proximity to and fixed relative to the light emitter and configured to (i) receive the reflected light beam, (ii) detect the particular wavelength of the reflected light beam, and (iii) transmit a color signal indicating the particular wavelength of the reflected light beam. The sensor further includes processing circuitry disposed in electrical communication with the color sensor and configured to receive the color signal and calculate the angle of incidence based on the particular wavelength.

Abstract: A flash-bang projectile that generates one or more noise pulses and one or more flashes of light. In generating a noise pulse, the flash-bang projectile provides a housing that includes a gas chamber that entraps air. The gas chamber includes a compression device that, when the flash-bang projectile is shot or otherwise ejected by a gun or other form of ejection device, compresses the air that is entrapped in the gas chamber. A burst disk forms one wall of the gas chamber and is configured to rupture a selected time delay after the air has been compressed. Rupturing of the burst disk releases the compressed air entrapped in the gas chamber, allowing the air to be released through a horn nozzle, thereby generating a noise pulse. The flash-bang projectile may have more than one gas chambers, with associated compression devices, whose burst disks are configured to rupture with diverse time delays, in which case the flash-bang projectile can generate multiple noise pulses with corresponding delays.

Abstract: An optical element, such as a lens, is described that provides good transmission of radiation in the infrared portion of the electromagnetic spectrum, that can be molded using an injection molding technique. The optical element comprises a moldable matrix in which is distributed a plurality of particles. The material comprising the matrix is selected so as to have a relatively low absorption of radiation in the infrared portion of the electromagnetic spectrum, and the material comprising the particles is selected to have a relatively high transmissivity of radiation in the infrared portion of the electromagnetic spectrum, and both materials are selected so as to have approximately the same index of refraction. The optical element comprising the matrix/particle composite is formed to provide surfaces having the contours that are required to provide the desired optical properties.