Abstract: A reconfigurable sensor monitoring system includes software tunable filters, each of which is programmable to condition one type of analog signal. A processor coupled to the software tunable filters receives each type of analog signal so-conditioned.

Abstract: A reconfigurable drive current system includes drive stages, each of which includes a high-side transistor and a low-side transistor in a totem pole configuration. A current monitor is coupled to an output of each drive stage. Input channels are provided to receive input signals. A processor is coupled to the input channels and to each current monitor for generating at least one drive signal using at least one of the input signals and current measured by at least one of the current monitors. A pulse width modulation generator is coupled to the processor and each drive stage for varying the drive signals as a function of time prior to being supplied to at least one of the drive stages.

Abstract: Air filter and cable management assemblies for network communication systems are disclosed. The assemblies include filters that cover one or more communication line cards and their associated connection panels. The assemblies also include cable support structures with cable support brackets that support connected cables while restricting airflow so that airflow is forced through the filter towards the connection panels. This airflow can then pass into housings for the line cards and other circuitry, such as fabric cards, to provide desired cooling. Fan subsystems can also be provided to facilitate airflow. Advantageously, the disclosed air filter and cable management assemblies allow for filtered cooling of stacked network communication systems while greatly simplifying the complexity of the filter and cable installation and maintenance.

Abstract: A short-range communication system includes an antenna, a transmitter, and a receiver. The antenna is an electrical conductor formed as a planar coil with rings thereof being uniformly spaced. The transmitter is spaced apart from the plane of the coil by a gap. An amplitude-modulated and asynchronous signal indicative of a data stream of known peak amplitude is transmitted into the gap. The receiver detects the coil's resonance and decodes same to recover the data stream.

Abstract: Systems, methods and apparatus are provided through which in some implementations determine the amplitude of an amplitude modulated signal, modulated by the position of an object being sensed. In some aspects, the apparatus accepts an excitation signal and the amplitude modulated signal and divides the amplitude modulated by the excitation signal to produce an output signal that is proportional to the position of the object being sensed. In other aspects, the division is performed only when the excitation signal is non-zero, such as close to the peaks in the excitation signal. In other aspects, the excitation signal and amplitude modulated signal are degraded due to an air gap and the degraded signals are used to correct for amplitude fluctuations due to the air gap, and produce an output signal, tolerant of the air gaps, that is proportional to the position of the object being sensed.

Abstract: A method and system are provided for sensing the position of a rotor in a hybrid stepper motor. First and second Hall sensors are positioned in a spaced-apart relationship with the first and second armatures of the rotor such that the first and second Hall sensors generate electrical outputs that are 90° out of phase with one another as the rotor rotates. The electrical outputs are adjusted relative to a reference, and the amplitude of the electrical outputs is further adjusted to account for spacing differences between the rotor and each of the first and second Hall sensors.

Abstract: A self-contained power controller having a power driver switch, programmable controller, communication port, and environmental parameter measuring device coupled to a controllable device. The self-contained power controller needs only a single voltage source to power discrete devices, analog devices, and the controlled device. The programmable controller has a run mode which, when selected, upon the occurrence of a trigger event changes the state of a power driver switch and wherein the power driver switch is maintained by the programmable controller at the same state until the occurrence of a second event.

Abstract: A miniature assembly is disclosed which includes a housing assembly with a cover configured to be sealably secured to a box-like receptacle. The receptacle comprises openings on opposing sides for the seating therein of communications connectors. Enclosed within housing is custom-sized circuit board for supporting, at least, a standard communications interface and at least one electronic device.

Abstract: A limit and position sensing system includes a sensor assembly and an emitter. The sensor assembly includes first and second electrical conductors arranged in opposing parallel planes. The first electrical conductor is coiled outwardly from either end thereof in a clockwise fashion to form a first coil region and a second coil region. The second electrical conductor forms a single coil with portions of the single coil's rings lying between the first end and second end of the first electrical conductor being parallel to an axis of the first electrical conductor's plane. Ferromagnetic material is aligned with the first and second electrical conductors and spans beyond (a) the first and second ends of the first electrical conductor, and (b) the portions of the rings of the second electrical conductor's single coil that lie between the first end and second end of the first electrical conductor.

Abstract: A motor controller system uses a rotary sensor with a plurality of signal conditioning units, coupled to the rotary sensor. Each of these units, which is associated with a particular range of motor output shaft rotation rates, generate a feedback signal indicative of the position of the motor's output shaft. A controller (i) converts a selected motor output shaft rotation rate to a corresponding incremental amount of rotational movement for a selected fixed time period, (ii) selects, at periodic completions of the selected fixed time period, the feedback signal from one of the signal conditioning units for which the particular range of motor output shaft rotation rates associated therewith encompasses the selected motor output shaft rotation rate, and (iii) generates a motor drive signal based on a difference between the incremental amount of rotational movement and the feedback signal from the selected one of the signal conditioning units.

Abstract: The parallel virtual directory system can extend the native file system to provide a superior method for organizing a computer system's physical storage devices or locations. These can include hard disks and removable media or remote storage locations such as on the Internet. Interceptor modules can monitor all file or memory changes such as creations, writes and deletes to the native file system and can pass this information to the parallel virtual directory system. The parallel virtual directory system may be accessed through the native file system methods allowing users to view their file system as it existed at any point in time, including removable media that is no longer present in the system. Further, via the parallel virtual directory system and the Interceptor modules, users can access any file in any of the monitored file systems.

Abstract: The parallel virtual directory system can extend the native file system to provide a superior method for organizing a computer system's physical storage devices or locations. These can include hard disks and removable media or remote storage locations such as on the Internet. Interceptor modules can monitor all file or memory changes such as creations, writes and deletes to the native file system and can pass this information to the parallel virtual directory system. The parallel virtual directory system may be accessed through the native file system methods allowing users to view their file system as it existed at any point in time, including removable media that is no longer present in the System Further, via the parallel virtual directory system and the Interceptor modules, users can access any file in any of the monitored file systems.

Abstract: The parallel virtual directory system can extend the native file system to provide a superior method for organizing a computer system's physical storage devices or locations. These can include hard disks and removable media or remote storage locations such as on the Internet. Interceptor modules can monitor all file or memory changes such as creations, writes and deletes to the native file system and can pass this information to the parallel virtual directory system. The parallel virtual directory system may be accessed through the native file system methods allowing users to view their file system as it existed at any point in time, including removable media that is no longer present in the system. Further, via the parallel virtal directory system and the Interceptor modules, users can access any file in any of the monitored file systems.

Abstract: A position sensor, such as a rotary position sensor, includes the signal-conditioning electronics in the housing. The signal-conditioning electronics are disposed on a printed wiring board, which is assembled with another printed wiring board including the sensor windings to provide a sub-assembly. A mu-metal shield is interposed between the printed wiring boards to prevent magnetic interference. The sub-assembly is disposed in the sensor housing adjacent to an inductor board which turns on a shaft. The inductor board emanates an internally or externally generated excitation signal that induces a signal in the sensor windings. The induced signal represents the rotary position of the inductor board relative to the sensor winding board.

Abstract: A position sensor or controller generates a response signal in existing armature windings of an actuator and detects the response signal to determine the position of the armature. To generate the response signal, the actuator includes a sensor excitation winding near the armature. Two sensor excitation windings can be provided, above and below the armature, to cancel out z components and thus allow for a variable gap. The sensor excitation winding or windings are supplied with an excitation signal to induce the response signal in the armature windings. The response signal is derived by differentially amplifying and frequency filtering a raw output of the armature windings. The response signal is demodulated to determine position. If a position controller rather than a mere sensor is desired, the position signal can be buffered, PID compensated, amplified, and fed back to the armature windings.

Abstract: The parallel virtual directory system can extend the native file system to provide a superior method for organizing a computer system's physical storage devices or locations. These can include hard disks and removable media or remote storage locations such as on the Internet. Interceptor modules can monitor all file or memory changes such as creations, writes and deletes to the native file system and can pass this information to the parallel virtual directory system. The parallel virtual directory system may be accessed through the native fie system methods allowing users to view their file system as it existed at any point in time, including removable media that is no longer present in the system. Further, via the parallel virtual directory system and the Interceptor modules, users can access any file in any of the monitored file systems.

Abstract: A system and method are provided for measuring rate of rotation. A brushless DC motor is rotated and produces a back electromagnetic force (emf) on each winding thereof. Each winding's back-emf is squared. The squared outputs associated with each winding are combined, with the square root being taken of such combination, to produce a DC output proportional only to the rate of rotation of the motor's shaft.

Abstract: A device suitable for determining arc-tangent of an angle .theta. is provided. Circuitry generates a first square wave at a frequency .omega.t and a second square wave at the frequency .omega.t but shifted by a phase difference equal to the angle .theta.. A pulse width modulation signal generator processes the first and second square waves to generate a pulse width modulation signal having a frequency of .omega.t and having a pulse width that is a function of the phase difference .theta.. The pulse width modulation signal is converted to a DC voltage that is a linear representation of the phase difference .theta..

Abstract: The converter produces a linear analog signal that is linearly proportional to a shaft angle of a resolver over 360.degree.. An excitation cosine signal supplied to the resolver and a response cosine signal received from the output windings of the resolver are converted to logic level signals. Digital logic is performed on the logic level signals in a programmable digital logic device to produce a logic level pulse-width modulated signal. The logic level pulse-width modulated signal is used to control a switch to switch between two reference voltage levels to produce a pulse-width modulated signal, which is filtered and buffered to produce the linear analog signal.

Abstract: A system and method are provided for measuring rate of rotation. A brushless DC motor is rotated and produces a back electromagnetic force (emf) on each winding thereof. Each winding's back-emf is integrated and multiplied by the back-emf associated with an adjacent winding. The multiplied outputs associated with each winding are combined to produce a directionally sensitive DC output proportional only to the rate of rotation of the motor's shaft.