Abstract: Power supply and drive device for a permanent magnet motor including a full-wave voltage rectifier stage, which can be supplied with an alternating current voltage to provide a rectified voltage, a power factor corrector stage, a smoothing capacitor to provide a direct current voltage and a motor drive stage, which is supplied with the direct current voltage and provides a signal indicating the power required by the motor. The smoothing capacitor is not of the electrolytic type and the power factor corrector stage has feedback control means to generate a reference current as a function of the direct current voltage and of the signal indicating the power required and to control an input current of the power factor corrector stage as a function of the reference current.

Abstract: A technology for a prosthetic above-knee device is provided. A socket may be used to attach the device to a residual limb, and may have a rigid body coupled to the socket. The device may include a first link with a first link end coupled through the rigid body to the socket and a second link end coupled to the rigid body. The second link of the device may have a third link end attached to the rigid body, and a fourth link end coupled to a housing. The device may include a hydraulic cylinder with a piston and a hydraulic cylinder link coupled between the rigid body and the piston of the hydraulic cylinder. The stability adjustment nut may adjust a travel distance of the hydraulic cylinder link with respect to the hydraulic cylinder to provide an adjustment of an instant center for stability modification.

Abstract: A method and a circuit arrangement is described by means of which a stepper motor can be operated by an adaptive control over a large rotational speed range, including a standstill, in which the motor is electrically fixed in a specific rotational position, and with high precision and running smoothness corresponding to a specified motor current course. This is achieved essentially by the fact that the motor is operated in a low rotational speed range including a standstill with a voltage-controlled or voltage-regulated first operating mode and in a higher or high rotational speed range with a current-controlled second operating mode.

Abstract: A method and a circuit assembly for driving a 2-, 3- or more phase stepper motor by predetermined courses of current curves, especially for a microstep operation, is disclosed. For minimizing the memory capacity needed for storing supporting points of the course of the current curve by which the microsteps are realized, the course of the current curve is divided into a number of segments to which each a basic or main gradient between adjacent supporting points is assigned, so that for each of the supporting points only a deviation of the gradient at this supporting point from the related basic or main gradient has to be stored.

Abstract: A servo-drive system for feedback-based control of motion and positioning of a motor comprises a current measurement device that obtains a measure of current being drawn by the drive motor from which to provide feedback. The current has an operating range which is made up of a relatively large current range for acceleration but remains within a relatively smaller current range for steady state operating of the motor. The current measurement device has a first, coarse, sensor optimized for measuring the relatively large current range and a second, fine, sensor optimized for measuring the relatively smaller current range, thereby to maximize feedback accuracy during steady state operation.

Abstract: A prosthetic hand system may include a plurality of prosthetic fingers and a prosthetic thumb. The prosthetic hand system may include a thumb drive mechanism that may be used to actuate the prosthetic thumb. In some examples, the thumb drive mechanism may be configured to enable the prosthetic thumb to perform a pinching or grasping motion and a release motion. The prosthetic hand system may also include a backlock that enables the prosthetic thumb to maintain pinching or gripping pressure after a motor has been disengaged. The prosthetic hand system may also include a gear lock that may be configured to lock a finger joint. The prosthetic hand system may also include an adaptive gripping joint that may be located on each prosthetic finger. In some examples, the adaptive gripping joint may be configured to passively adapt the plurality of prosthetic fingers to one or more differently shaped objects.

Abstract: An electrical machine (10) has three phase windings (12). Each phase winding (12) is connected to a respective current source (18). Each current source 18 provides alternating current to the corresponding winding (12). The current source 18 is connected independently to the respective winding (12). The electrical angles of the phase windings (12) are so arranged that none of the phase windings (12) has a zero torque angle which coincides with a zero torque angle of another phase winding (12).

Abstract: An apparatus, a system and a method use a light-emitting diode (LED) to identify the presence of a material in a gas and/or a fluid and/or to determine properties of the material. The LED and a light detector may be used to determine a chemical compound in the material. The gas and/or the fluid may be located in a chamber. A first light detector may be positioned on the opposite side of the chamber relative to the LED, a second light detector may be positioned on the same side of the chamber as the LED, and/or a third light detector may be positioned inside the chamber. Additional light detectors with coatings may enable measurements to be corrected for the effects of temperature. The light detectors may determine light reflection, light refraction, light transmission, light diffraction, light interference, light diffusion, light collimation, light absorption and/or light focusing of the material.

Abstract: A method and a circuit arrangement are provided in which a mechanical load applied to the motor shaft or a load angle of the motor can be detected without sensors in a stepper motor. This is achieved substantially based on the fact that the load or the load angle creates a mutually induced voltage (back EMF) in the motor coils and the load or the load angle is detected by determining the phase shift of the motor voltage at at least one of the motor coil relative to the coil current at said motor coil connection, the phase shift being caused by the mutually induced voltage. A method and a circuit arrangement are also provided wherein the motor current of a stepper motor can be controlled according to load angle in such a way that the current consumption of the motor is relatively low.

Abstract: A method and circuit arrangement for controlling the motor current in an electric motor, in particular a stepper motor, by a chopper method is provided. In the method/circuit arrangement, the motor is operated with a coil current that follows a target coil current substantially more accurately at least at the zero crossing of the coil current. The method/circuit arrangement provides a good symmetry of the sinusoidal wave shape of the coil current with respect to the zero crossing of the coil current. The method is achieved in particular by the active control of the coil current both in the direction of a predefined target coil current and opposite the direction of the predefined target coil current with respect to upper or lower desired current values and a lowering or increasing of the upper or lower desired current values.

Abstract: A method and a circuit assembly for driving a 2, 3- or more phase stepper motor by predetermined courses of current curves, especially for a microstep operation, is disclosed. For minimizing the memory capacity needed for storing supporting points of the course of the current curve by which the microsteps are realized, the course of the current curve is divided into a number of segments to which each a basic or main gradient between adjacent supporting points is assigned, so that for each of the supporting points only a deviation of the gradient at this supporting point from the related basic or main gradient has to be stored.

Abstract: A method and circuit assembly are provided for controlling the motor current in an electric 3-phase motor, in particular in a 3-phase stepper motor, by a chopper process. For at least two of the three motor connections a respective chopper phase is cyclically activated, while a target motor current supplied for the motor connection in question is injected into the motor connection by a chopper process, while the two other motor connections are connected to each other.

Abstract: Compositions are provided for a prosthetic ankle comprising: a joint housing having a bottom surface, a clevis coupled to the joint housing such that the clevis can rotate about the joint housing, a prosthetic coupling structure that couples the clevis to an amputee, and an articulating joint contained in the joint housing. Additionally, a portion of the bottom surface of the joint housing can be curved allowing a substrate a preset amount of flexion when coupled thereto and flexed in a concave position.

Abstract: A high load capacity bearing that includes a cylindrical outer sleeve that fits around a separable cylindrical outer race assembly. The outer race assembly includes a set of non-helical grooves formed on its inside surface that mesh and engage teeth formed on the outside surface of a plurality of rotating rollers that are longitudinally and axially aligned inside the outer race assembly. The rollers are longitudinally aligned and evenly space apart and rotated as a unit inside the outer race assembly. Located in side the rollers is an inner race with non-helical grooves formed on its outside surface that mesh and engage the teeth on the rollers. The inner race includes a smooth inside bore that fits around the support surface on a shaft.

Abstract: An electrical machine (10) has three phase windings (12). Each phase winding (12) is connected to a respective current source (18). Each current source 18 provides alternating current to the corresponding winding (12). The current source 18 is connected independently to the respective winding (12). The electrical angles of the phase windings (12) are so arranged that none of the phase windings (12) has a zero torque angle which coincides with a zero torque angle of another phase winding (12).

Abstract: A prosthetic hand system may include a plurality of prosthetic fingers and a prosthetic thumb. The prosthetic hand system may include a thumb drive mechanism that may be used to actuate the prosthetic thumb. In some examples, the thumb drive mechanism may be configured to enable the prosthetic thumb to perform a pinching or grasping motion and a release motion. The prosthetic hand system may also include a backlock that enables the prosthetic thumb to maintain pinching or gripping pressure after a motor has been disengaged. The prosthetic hand system may also include a gear lock that may be configured to lock a finger joint. The prosthetic hand system may also include an adaptive gripping joint that may be located on each prosthetic finger. In some examples, the adaptive gripping joint may be configured to passively adapt the plurality of prosthetic fingers to one or more differently shaped objects.

Abstract: A method and a circuit arrangement are provided which enable a mechanical load applied to the motor shaft of a stepper motor (M) or a load angle of the stepper motor to be detected in a sensorless manner. A method and circuit arrangement are also provided which enable the motor current(s) of a stepper motor to be controlled in accordance with the load value such that the load angle is as high as possible without risking step losses, in order to maintain the current consumption of the motor as low as possible. This is achieved according by evaluating the temporal duration of the ON- and the FD-phases during the chopper control of the motor.

Abstract: A method and circuit assembly are provided for controlling the motor current in an electric 3-phase motor, in particular in a 3-phase stepper motor, by a chopper process. For at least two of the three motor connections a respective chopper phase is cyclically activated, while a target motor current supplied for the motor connection in question is injected into the motor connection by a chopper process, while the two other motor connections are connected to each other.

Abstract: A method and circuit arrangement for controlling the motor current in an electric motor, in particular a stepper motor, by a chopper method is provided. In the method/circuit arrangement, the motor is operated with a coil current that follows a target coil current substantially more accurately at least at the zero crossing of the coil current. The method/circuit arrangement provides a good symmetry of the sinusoidal wave shape of the coil current with respect to the zero crossing of the coil current. The method is achieved in particular by the active control of the coil current both in the direction of a predefined target coil current and opposite the direction of the predefined target coil current with respect to upper or lower desired current values and a lowering or increasing of the upper or lower desired current values.

Abstract: A method and a circuit arrangement are provided which enable a mechanical load applied to the motor shaft of a stepper motor (M) or a load angle of the stepper motor to be detected in a sensorless manner. A method and circuit arrangement are also provided which enable the motor current(s) of a stepper motor to be controlled in accordance with the load value such that the load angle is as high as possible without risking step losses, in order to maintain the current consumption of the motor as low as possible. This is achieved according by evaluating the temporal duration of the ON- and the FD-phases during the chopper control of the motor.