Abstract: A gear shifting system for use on a derailleur equipped bicycle having automatic and manual modes of operation. A microcontroller is mounted to the bicycle frame. Sensors are also mounted to the frame to allow the microcontroller to determine the most efficient gear ratio based on the bicycle velocity and the user pedaling rate in the automatic mode of operation. Servomotors mounted to the bicycle frame are responsive to the outputs to drive the bicycle derailleur and provide the most efficient gear ratio. A control panel mounted to the bicycle handlebars allows the user to select either the automatic or manual operating mode, the latter allowing manual activation of the gear shifters through the microcontroller and servomotors. The microcontroller has at least two input capture functions responsive to bicycle velocity and the cadence, in the automatic mode, and two output compare functions which adjust the derailleurs accordingly.

Abstract: A method and associated means for producing simultaneous electrical representations of the electrical and acoustical (heart sound) activity of the heart, in which a pickup device and associated circuits produce a full wave rectified symmetrical heart sound signal annotated by pulses developed from the QRS wave of the electrocardiogram signal.The pickup device is designed to permit the direct (unbuffered) application of the pickup electrodes to the skin of the body and to provide a control of the associated circuits when not in contact with the body to shorten response times when the pickup device is placed in contact with the body.

Abstract: Image processing sections and associated circuitry for generating signals indicative of the centered moments of a sliding submatrix window of signals located within a larger image matrix are disclosed. The processing sections include registers for storing signals indicative of the columnar sums of the signals within an intermediate submatrix of signals and for storing the sum of a subset of the columnar sums that is thereby indicative of the sum of the signals within the sliding submatrix window and, further is equivalent to an uncentered moment of the signals within the sliding submatrix window. The signals stored in the registers are continuously updated as the sliding submatrix window is sequentially moved within the image matrix. The associated circuitry combines the uncentered moment signals to produce centered moment signals.

Abstract: A very high speed video imaging system wherein the video image from each video frame of M.sub.1 columns and M.sub.2 rows of video pixels is multiplexed serially by row, each image pixel corresponding to an address in said video frame; image enhancement processing is performed in real time, using r programmable processors operating on successive kernels comprising L.sub.1 rows and L.sub.2 columns of the image pixels. Real time image processing is made possible by multiple image copying means which furnishes multiple copies of the image pixels to the r processors, wherein each one of the processors receives a copy of only those image pixels having an address lying within an assigned range, which limits the amount of data handled by each processor for each video frame.

Abstract: An interferometric distance measurement method which utilizes a sequence of at least two closely spaced optical wavelengths in order to achieve ambiguity resolution during the measurement procedure. In so doing, this method performs the equivalent of measuring distances at a relatively long wavelength by measuring the phase difference at two closely spaced optical wavelengths and computing the effective phase measurement at a wavelength which corresponds to the frequency difference between the two optical wavelengths measured.

Abstract: A self-calibrating interferometer which forms therein a pair of Michelson interferometers with one beam length of each Michelson interferometer being controlled by a common phase shifter. The transfer function measured from the phase shifter to either of a pair of detectors is sinusoidal with a full cycle for each half-wavelength of phase shifter travel. The phase difference between these two sinusoidal detector outputs represents the optical phase difference between a path of known distance and a path of unknown distance.

Abstract: An improved homodyne receiver for use in wideband optical communications systems is disclosed. The receiver utilizes quadrature demodulation of the optical signal in the manner of a two-phase receiver. A beam-splitting/phase-splitting optical assembly is used to channelize the received and the local oscillator beams to a pair of optical detectors. Squaring amplifiers in the quadrature channels followed by a summing network provide an output signal which is proportional to the square of the modulation of the input signal. This receiver is especially well-suited to the reception of Pulse Code Modulated optical signals.

Abstract: A laser beam frequency modulation demodulator is disclosed utilizing the highly linear frequency versus voltage characteristic of the absorption resonance provided by a Stark-effect cell. An error signal, generated by dither modulation of the Stark-effect cell voltage, is fed back to the Stark-effect cell via a low-pass filter to cause the absorption resonance to track the instantaneous frequency of the laser beam. The feedback signal applied to the Stark-effect cell has an amplitude proportional to the frequency modulation on the laser beam.