75 results about "Stationary Reference Frame" patented technology

The present invention relates to a system for identifying the position of a machine in a fixed frame of reference, said machine standing on an essentially plane support surface. In the invention, the support surface is fitted with a plurality of interactive integrated bushings, each bushing being fitted with emitter means serving to emit a predetermined code enabling the bushing concerned to be identified and thus making it possible to deduce the coordinates of a point associated with said support surface, and the three-dimensional machine is fitted with at least one articulated arm terminating in a position sensor, said arm being fitted with receiver means capable of detecting the code emitted by a bushing amongst the plurality of bushings when the associated position sensor is brought into contact therewith.

An imaging sonar system develops three-dimensional images of the space below, to the sides, and forward of a ship relative to a fixed frame of reference. Various features permit the system to be used in non-military environments and make possible low cost with substantial capabilities.

A method of starting a permanent magnet machine. A machine stator voltage in a stationary reference frame is sensed. An initial speed of a rotor of the machine is estimated based on the sensed voltage, and state variables of control algorithms are initialized based on the estimated initial speed. This method can provide smooth startup and / or restart at any speed.

A method of starting a permanent magnet machine. A machine stator voltage in a stationary reference frame is sensed. An initial speed of a rotor of the machine is estimated based on the sensed voltage, and state variables of control algorithms are initialized based on the estimated initial speed. This method can provide smooth startup and / or restart at any speed.

A method of starting a permanent magnet machine. A machine stator voltage in a stationary reference frame is sensed. An initial speed of a rotor of the machine is estimated based on the sensed voltage, and state variables of control algorithms are initialized based on the estimated initial speed. This method can provide smooth startup and / or restart at any speed.

The present invention relates to an electrical power supply and control device (10) for equipment (9) of a rotor (5), the device having a three-phase AC generator (20) in a stationary frame of reference. The device (10) comprises a rotary field transformer (30) having a stationary portion (31) connected to said generator (20) and a rotary portion (32) connected to a sequencer (50) that is arranged in a rotary frame of reference, said device (10) including control means (51) for controlling the sequencer (50) and located in said stationary frame of reference, the control means being connected to the sequencer (50) via contactless connection means (200), said sequencer (50) being suitable for electrically powering said equipment (9) on order of said control means (51).

A short distance positioning system for a mobile object with respect to a fixed reference system. The mobile object is equipped with a probe, and at least one resonant circuit enabling reception of a magnetic field. A detection and comparison circuit detects the amplitude of the voltage induced at the terminals of the resonant circuit, thereby deducing the displacement of the probe with respect to the reference system.

A scanning force microscope (10) sometimes referred to as an atomic force microscope employs a laser (32) and a cantilever (28) which move proportionally to a moving reference frame (64). A fixed reference frame (11) contains optical components. A scanning mechanism creates relative movement between the fixed and moving reference frames. An optical assembly (114) is included which comprises at least one optical device in the fixed reference frame. The optical assembly permits initial alignment of the laser beam onto the cantilever and also permit the laser beam to follow the moving cantilever.

There is provided a method for estimating the orientation of an accelerometer relative to a fixed reference frame, the method comprising obtaining signals from the accelerometer, the signals indicating the components of the acceleration acting on the accelerometer along three orthogonal axes; identifying the axis with the highest component of acceleration; and determining the orientation of the accelerometer by determining the angle between the acceleration acting on the accelerometer and the axis with the highest component of acceleration. There is further provided a method for estimating the vertical acceleration in the fixed reference frame using the estimated orientation.

Continuous monitoring and fault diagnosis of rotating machinery during variable speed operation is performed using only a position feedback signal. The position sensor generates a periodic waveform having multiple pulses per revolution of the machine. A circuit is included to detect, for example, a zero crossing or edge of the periodic waveform. At each detected zero crossing or edge, the time and position of the event is stored in memory. Other data, such as the current in the motor, may also be sampled and stored in memory. Because the sampled data is triggered by repeated feature of the position feedback signal, the sampled data is in a stationary reference frame in the position domain. Frequency analysis is performed on the sampled data, and the frequency components present in either the sampled signal are analyzed to identify the presence of a fault in the rotating machinery.

A method of driving an alternating-current (AC) motor while periodically obtaining a rotator angle of the AC motor. The method includes: (a) driving the AC motor by a dS-axis voltage, which is a voltage for an exciting current in a stationary reference frame, and a qS-axis voltage, which is a voltage for generating a rotational force in the stationary reference frame, while sequentially applying different dS-axis voltages and different qS-axis voltages to the AC motor in a control injection period; and (b) obtaining a rotator angle by a dS-axis voltage value, a qS-axis voltage value, a dS-axis current value, and a qS-axis current value in the control injection period.

A method of controlling an inverter to includes determining the components of a phasor representing the output current from the inverter in a fixed reference system; determining the components of the current phasor in a reference system rotating at a velocity equal to the velocity of rotation of the phasor representing the grid voltage; and comparing the components of the current phasor in the rotating reference system with a reference, again expressed in the rotating reference system, to determine an error signal, by means of which the inverter is controlled.

The present invention relates to a wind turbine and a method of operating a wind turbine for reducing edgewise vibrations, wherein the wind turbine comprises a wind turbine control system having at least one vibration sensor for measuring the edgewise vibrations and a controller for receiving the vibration signal from the vibration sensor. The sensor unit is preferably an accelerometer arranged in a stationary frame of reference. The controller determines at least one whirling mode frequency and the vibration level thereof. The controller initiates a corrective action if the measured vibration level exceeds a threshold value. The corrective action is preferably an adjustment of the pitch angle of the wind turbine blades which in turn dampens the edgewise vibrations.

The invention belongs to the field of shock-absorbing technology researches, and specifically relates to a metal rubber shock-absorbing energy-consuming device controlled by a shape memory alloy structure in a vibration manner. The metal rubber shock-absorbing energy-consuming device consists of rubber elements, an upper layer connection steel plate, a lower layer connection steel plate, shape memory alloy wire bundles, smooth round rings and pulley wheels, the rubber elements are connected with the upper layer connection steel plate and the lower layer connection steel plate, the lower layer connection steel plate is connected with a fixed reference system, the upper layer connection steel plate is connected with a bearing object, the smooth round rings are uniformly distributed and welded on the upper layer connection steel plate and the lower layer connection steel plate and sleeved with the pulley wheels, and the shape memory alloy wire bundles and the pulley wheels are arranged on the periphery of a supporting seat through the smooth round rings. The invention combines characteristics of superelasticity and energy consumption of shape memory alloy and provides a novel shock-absorbing energy-consuming supporting seat made of the shape memory alloy. The metal rubber shock-absorbing energy-consuming device has the advantages that by means of the superelasticity and the energy consumption of the shape memory alloy, the multi-dimensional shock insulation of the structure is achieved, and shock insulation effects are improved.

A 3D pointing device utilizing an orientation sensor, capable of accurately transforming rotations and movements of the 3D pointing device into a movement pattern in the display plane of a display device is provided. The 3D pointing device includes the orientation sensor, a rotation sensor, and a computing processor. The orientation sensor generates an orientation output associated with the orientation of the 3D pointing device associated with three coordinate axes of a global reference frame associated with the Earth. The rotation sensor generates a rotation output associated with the rotation of the 3D pointing device associated with three coordinate axes of a spatial reference frame associated with the 3D pointing device itself The computing processor uses the orientation output and the rotation output to generate a transformed output associated with a fixed reference frame associated with the display device above. The transformed output represents a segment of the movement pattern.