Abstract: A current measurement module is adapted to measure an observed current level for the inverter. A data processor or mode controller accesses a stored representation of first current level versus rotor speed output at which a total harmonic distortion level is less than threshold total harmonic distortion level. The data processor or mode controller enables the inverter to use SVPWM (space vector pulse width modulation) if the observed current level is less than the first current level for the measured or determined rotor speed. Further, the data processor or mode controller enables the inverter to use DPWM (discontinuous pulse width modulation) if the observed current level is greater than or equal to the first current level for the measured or determined rotor speed.

Abstract: A current measurement module is adapted to measure an observed current level for the inverter. A data processor or mode controller accesses a stored representation of first current level versus rotor speed output at which a total harmonic distortion level is less than threshold total harmonic distortion level. The data processor or mode controller enables the inverter to use SVPWM (space vector pulse width modulation) if the observed current level is less than the first current level for the measured or determined rotor speed. Further, the data processor or mode controller enables the inverter to use DPWM (discontinuous pulse width modulation) if the observed current level is greater than or equal to the first current level for the measured or determined rotor speed.

Abstract: In a powered actuator for supplying torque, joint equilibrium, and/or impedance to a joint, a motor is directly coupled to a low-reduction ratio transmission, e.g., a transmission having a gear ratio less than about 80 to 1. The motor has a low dissipation constant, e.g., less than about 50 W/(Nm)2. The transmission is serially connected to an elastic element that is also coupled to the joint, thereby supplying torque, joint equilibrium, and/or impedance to the joint while minimizing the power consumption and/or acoustic noise of the actuator.

Abstract: At least one example embodiment discloses a method of controlling an alternating current (ac) machine. The method includes determining or retrieving a current limit for the ac machine, determining a characterized peak current value based on a voltage-to-speed ratio of the ac machine, determining current command values for the ac machine based on at least one of the torque command limit and a torque command for the ac machine, determining current command values for the ac machine based on the torque command limit and controlling the ac machine based on the current command values.

Abstract: At least one example embodiment discloses a method including measuring phase currents associated with one or more stator windings of the machine, estimating terminal voltage values based on the measured phase currents representations of the machine and based on at least one of a duty cycle and a dead time ratio of the machine, transforming the terminal voltage values to derive direct and quadrature voltage representations consistent with the measured phase currents, determining a terminal power of one or more terminals of the machine, the terminal power directly based on one of the estimated terminal voltage values and direct and quadrature voltage representations of the machine and current command values and determining an estimated shaft torque of the machine based on the terminal power in accordance with at least one efficiency value based on machine parameters from a characterization of the machine.

Abstract: A rotor blade for use in a turbine of a combustion turbine engine. The rotor blade may include an airfoil having a concave pressure sidewall and a convex suction sidewall extending axially between corresponding leading and trailing edges and radially between the root and an outboard tip. The rotor blade may further include dual snubber shrouds positioned on the airfoil. Each of the dual snubber shrouds may be configured to engage a corresponding snubber shroud on at least one neighboring rotor blade upon installation.

Abstract: At least one example embodiment discloses a control device for controlling an alternating current (ac) machine. The control device includes a processor configured to select a modulation mode from a plurality of modulation modes, determine a plurality of present phase voltages corresponding to phases of an inverter based on the selected modulation mode, the determination compensating for deadtimes associated with the selected modulation mode and phases of the inverter, the inverter configured to drive the ac machine and determine an estimated terminal voltage based on the plurality of present phase voltages.

Abstract: A solar energy system and method of cleaning photovoltaic panels is provided. Measurements relating to weather at a photovoltaic panel are received by the system. Measurements relating to output current and voltage at the photovoltaic panel are received by the system. Expected power of the photovoltaic panel is determined based on the measurements relating to weather. Actual power of the photovoltaic panel is determined based on the measurements relating to output current and voltage. In response to determining that the actual power is not within a predetermined range of the expected power (e.g. at least one photovoltaic panel is dirty), a cleaning of the photovoltaic panel is initiated.

Abstract: A knee prosthesis comprises an agonist-antagonist arrangement of two series-elastic actuators in parallel, including a knee joint, flexion and extension actuators connected to the joint in parallel with a leg member, and a controller for independently energizing the actuators to control the movement of the knee joint and leg. The flexion actuator comprises the series combination of a flexion motor and a flexion elastic element and the extension actuator comprises the series combination of an extension motor and an extension elastic element. Sensors provide feedback to the controller. The flexion actuator and the extension actuator may be unidirectional, with the flexion and extension elastic elements being series springs. The extension actuator may alternatively be bidirectional, with the extension elastic element being a set of pre-compressed series springs. Alternatively, the flexion elastic element may be a non-linear softening spring and the extension elastic element may be a non-linear hardening spring.

Abstract: A system includes a turbomachine that includes a stator and a rotor. The rotor is configured to rotate about a rotational axis relative to the stator. In addition, the rotor includes a least one rotary blade, and the at least one rotary blade has a patterned structure of beams and cavities.

Abstract: A knee prosthesis comprises an agonist-antagonist arrangement of two series-elastic actuators in parallel, including a knee joint, flexion and extension actuators connected to the joint in parallel with a leg member, and a controller for independently energizing the actuators to control the movement of the knee joint and leg. The flexion actuator comprises the series combination of a flexion motor and a flexion elastic element and the extension actuator comprises the series combination of an extension motor and an extension elastic element. Sensors provide feedback to the controller. The flexion actuator and the extension actuator may be unidirectional, with the flexion and extension elastic elements being series springs. The extension actuator may alternatively be bidirectional, with the extension elastic element being a set of pre-compressed series springs. Alternatively, the flexion elastic element may be a non-linear softening spring and the extension elastic element may be a non-linear hardening spring.

Abstract: The system and method for handling email messages having at least one attachment. The system checks each outgoing email for attachments that are larger than a predefined size, detaches each such attachment from the email message, and splits each such attachment into segments. The system sends each of the segments to the addressees in separate emails so that each sent email is of a size less than the predefined threshold size. The system also includes a function that screens incoming emails or an inbox for split mail messages with separated attachments. For each detected split mail message, the system reassembles the original email along with the attachments.

Abstract: A knee prosthesis comprises an agonist-antagonist arrangement of two series-elastic actuators in parallel, including a knee joint, flexion and extension actuators connected to the joint in parallel with a leg member, and a controller for independently energizing the actuators to control the movement of the knee joint and leg. The flexion actuator comprises the series combination of a flexion motor and a flexion elastic element and the extension actuator comprises the series combination of an extension motor and an extension elastic element. Sensors provide feedback to the controller. The flexion actuator and the extension actuator may be unidirectional, with the flexion and extension elastic elements being series springs. The extension actuator may alternatively be bidirectional, with the extension elastic element being a set of pre-compressed series springs. Alternatively, the flexion elastic element may be a non-linear softening spring and the extension elastic element may be a non-linear hardening spring.

Abstract: A turf machine is disclosed having a body with an engine and a mower deck. The turf machine has a plurality of track drives coupled to the engine. The turf machine further has a forward power coupling which transfers power from the engine to the mower deck.

Abstract: A lid includes a top having a cover receiving portion having a first aperture and a second aperture formed therein, a hinge positioned about a center of the cover receiving portion such that the first aperture is on one side of the hinge and the second aperture is on an opposite side of the hinge, and a cover having two directly opposing sidewalls rotatably attached to the cover receiving portion via the hinge. Each sidewall includes a protrusion extending therefrom shaped to fit within one of the first and second apertures. The cover pivots relative to the cover receiving portion so as to engage either the first aperture or the second aperture, and when the protrusion on one sidewall of the cover is pivoted towards the first aperture, the protrusion on the other sidewall simultaneously pivots away from the second aperture.

Abstract: First stage turbine buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth Table I wherein X and Y values are in inches and the Z values are non-dimensional values from 0.05 span to 0.95 span convertible to Z distances in inches by multiplying the Z values by the height of the airfoil in inches. The X and Y values are distances which, when connected by smooth continuing arcs, define airfoil profile sections at each distance Z. The profile sections at each distance Z are joined smoothly to one another to form a complete airfoil shape. The X, Y and Z distances may be scalable as a function of the same constant or number to provide a scaled up or scaled down airfoil section for the bucket. The nominal airfoil given by the X, Y and Z distances lies within an envelope of ±0.150 inches in directions normal to the surface of the airfoil.

Abstract: Systems and methods for controlling diesel engine emissions, including, for example, oxides of nitrogen emissions, particulate matter emissions, and the like. The emission control system according to this invention is provided in the exhaust passageway of a diesel engine and includes a catalyst-based particulate filter; and first and second lean NOx trap systems coupled to the catalyst-based particulate filter. The first and second lean NOx trap systems are arranged in a parallel flow configuration with each other. Each of the first and second lean NOx trap systems include a carbon monoxide generating catalyst device, a sulfur trap device, a lean NOx device, a supplemental fuel injector device, and a plurality of flow diverter devices.

Abstract: A lid includes a flat portion having a first aperture and a second aperture formed therein, a hinge positioned about a center of the flat portion such that the first aperture is on one side of the hinge and the second aperture is on an opposite side of the hinge, a cover, having two directly opposing sidewalls each with a protrusion, rotatably attached to the flat portion via the hinge, a valve housing integrally formed with the flat portion, a valve, and a valve retainer for retaining the valve within the valve housing. The cover pivots relative to the flat portion so as to engage either the first aperture or the second aperture, and when the protrusion on one sidewall of the cover is pivoted towards the first aperture, the protrusion on the other sidewall simultaneously pivots away from the second aperture.

Abstract: A zero to 100% continuously adjustable, low deadband, point contact pneumatic level switch is used in conjunction with an electronic controller, a pneumatic-to-current converter and a current-to-pneumatic converter to control brine level in a gravity-fed batch process. The apparatus includes a flapper disc assembly that is free to rotate or spin in place as the mechanism tracks the level of the fluid and a nozzle to seal, expel and transmit a pneumatic signal for measurement or control of fluid level. The flapper disk/nozzle assembly does not come in contact with the controlled fluid.