Abstract: A stator for an electric machine includes a generally cylindrical stator core having a plurality of circumferentially-spaced and axially-extending core teeth that define a plurality of circumferentially-spaced and axially-extending core slots in a surface thereof, a main winding having a plurality of coils, each of the coils including a plurality of turns occupying the plurality of slots in the stator core, and a tertiary excitation winding having a plurality of coils, each of the coils including a single turn occupying at least a subset of the plurality of slots in the stator core. The coils of the main winding are unevenly arranged in the plurality of slots.

Abstract: An overhead door having a floating spring adjustment is presented. Tension is applied to a torsion spring while the door is in the open, minimal tension state. One end of the torsion spring is fixed to a spring tension trolley. The trolley translates within a trolley guide mounted to the building structure. The other end of the torsion spring is fixed to a shaft running through the torsion spring. This allows the torsion spring to change in length as the number of coils shrink and grow through door operation thereby eliminating the “snake-like” or serpentine appearance from an improper fixed torsion spring length.

Abstract: Robustly stabilizing controller bandwidth for a controlled mechanical system is determined as a function of the system's estimated inertia and dominant system parameters that define constraints on the bandwidth. In one or more embodiments, a bandwidth model is derived that defines a relationship between robustly stabilizing controller bandwidth and system gain over a range of reasonable system uncertainties. Using the model, a suitable controller bandwidth can be determined for a given motion control system given only estimates of the system gain and the dominant parameters(s) that constrain the bandwidth. In an example two-inertia system, the system gain and dominant parameter can comprise system inertia and mechanical coupling stiffness, respectively. Accordingly, estimates of the system inertia and coupling stiffness can be provided to the system, which determines a suitable controller bandwidth for the motion control system characterized by the estimates.

Abstract: An apparatus for testing the performance of a synthetic aperture radar is provided. The apparatus for testing the performance of a synthetic aperture radar includes: a three-axis motion platform that is coupled to an antenna and driven in roll, pitch, and yaw directions so as to reproduce motion components generated from a pointing plane of the antenna; a target simulator configured to reproduce a ground target; and a system simulator that allows the three-axis motion platform and the target simulator to work in conjunction with each other in real time, and controls the three-axis motion platform and the target simulator. Here, the three-axis motion platform may include a three-axis driver that determines the attitude of the three-axis motion platform, based on position and speed information received from the system simulator.

Abstract: A shift register which receives a transmission clock signal, which is shifted according to the transmission clock signal, and which outputs a gate signal a predetermined time after reset; a reset circuit which outputs a reset signal for resetting the shift register when the reset circuit receives an input of a step signal for driving the stepping motor; and a switching element which receives the gate signal of the shift register and which is switched between a blocked state and a conductive state are provided in a driving circuit of a stepping motor.

Abstract: The resolver input module for use in programmable controller systems is one of several modules mounted in a rack to form a programmable controller. The module's function is to provide position data from an externally located resolver which is connected to a machine's shaft to the programmable controller's processor module. This is accomplished by moving the resolver analog-to-digital conversion circuitry from an external module location to the programmable controller input/output rack and coupling this circuitry to circuits which synchronize the programmable controller's input fetch signals. Additionally, a user operable entry mechanism for digitally offsetting the resolver position by a user-selectable amount while accommodating different scale factors is provided. Synchronization and alignment circuitry are provided for synchronizing and aligning data to compensate for different resolver gear ratios in coarse-fine geared resolver decoding circuitry.

Abstract: A system for transmitting an EPR (Engine Pressure Ratio) from a gas turbine is provided with a resolver component (30) which modifies the EPR in accordance with variations in the optimum EPR for a particular turbine under particular conditions. The information from an EPR gauge is transmitted by a synchro transmitter, and is received by a differential transmitter (31) associated with the particular engine being monitored. The differential transmitter (31) is adjusted in accordance with pressure (at 33) and temperature (at 56) conditions in order to provide an EPR reading which is compensated in accordance with actual conditions of pressure and temperature. The differential transmitter (31) is also adjusted (at 45) in order to provide an output which is further varied in accordance with a variation in the optimum EPR under standard conditions for the particular turbine associated with the differential transmitter.

Abstract: An apparatus and method for generating clock pulses to an electronically controlled glassware forming machine from the variable frequency power present in a power selsyn multiple motor drive system is disclosed. The frequency of the power present in the selsyn rotor windings is subtracted from the frequency of the power present in the selsyn stator windings to generate a difference frequency signal. The difference frequency signal has a frequency which is directly proportional to the speed of the rotating selsyn rotors. The difference frequency signal can be scaled to provide a desired number of clock pulses and reset pulses per machine cycle.

Abstract: A dual mode servo-system providing improved motion characteristics and improved noise immunity. A relatively movable member is driven by control signals derived from actual velocity feedback signals during coarse mode operation. At the beginning of fine mode operation the actual velocity signal is sampled and used to generate a synthetic velocity signal used to control motion of the member during final deceleration, along with an actual position feedback signal, the synthetic velocity signal having a decreasing magnitude tailored to a particular application. At a predetermined maximum time period, after detent of the member, a time out circuit re-inserts the actual velocity feedback signal.Control signals for the driven member are also derived from the actual motor current by integrating the motor current, the integrated current signals being used to control motion of the member during coarse mode operation only.

Abstract: A two-speed resolver system wherein the rotor of a fine brushless resolver which is directly connected to the shaft to be instrumented is connected to the rotor of a coarse resolver so that the rotor ofthe coarse brushless resolver rotates at a proportional but different rate than the fine resolver and the electrical output of the fine resolver which represents the position of the input shaft is fed to the electrical input on the coarse resolver and combined with the mechanical input to the coarse resolver to provide a signal out of the coarse resolver which indicates a predetermined fraction of angular rotation for each revolution of the rotor of the fine resolver. The disclosed two-speed resolver system utilizes brushless resolvers wherein the electrical connections to the rotors are through brushless rotary transformers. Two gears having a different number of teeth can be used to couple the rotor of the fine resolver to the rotor of the coarse resolver.