Angular displacement

About: Angular displacement is a research topic. Over the lifetime, 5102 publications have been published within this topic receiving 46081 citations. The topic is also known as: rotational displacement.

Improved multi-directional eddy current inspection test apparatus for detecting flaws in metal articles

Abstract: Apparatus is described for detecting flaws in a tubular workpiece in a single scan. The coils of a dual coil bobbin eddy current inspection probe are wound at a 45° angle to the transverse axis of the probe, one coil having an angular position about the axis about 90° relative to the angular position of the other coil, and the angle of intersection of the planes containing the coils being about 60°.

Technique for sensing the rotational speed and angular position of a rotating wheel using a variable threshold

Abstract: To detect the rotational speed and angular position of a rotating wheel, a non-contact sensor (e.g., an optical sensor or a Hall sensor) scans scan marks on the wheel, and generates a pulse train. The amplitude of the pulses is compared in a comparator with a variable switching threshold. To achieve accurate measurement results, and to compensate for offset and long-term drift of the sensor, the switching threshold is adjusted if one or more of the following conditions is met: (i) the difference between the pulse amplitude and the switching threshold exceeds a fixable first maximum, (ii) the difference of the amplitudes of two successive pulses exceeds a fixable second maximum, (iii) the difference of the frequencies of successive pulses exceeds a fixable third maximum. The method is particularly advantageous in a motor vehicle, to detect the rotational speed and angular position for an electronic ignition system, or the rotational speed and angular position of the wheels for an ABS braking system, an anti-skid system, or a vehicle stabilization system.

Start-up procedure for brushless DC motors having position sensors with angular resolution lower than the resolution of the driving system

Abstract: A start-up routine is provided for a multiphase brushless DC motor having one or more rotor position sensors insufficient to provide for an angular resolution as high as the angular resolution of the synchronized driving system of the motor. The start-up routine includes setting at least an angular check zone having a certain arc length angularly correlated to the one or more rotor position sensors, assuming a certain initial rest position of the rotor, and exciting for fixed time intervals the phase windings in a sequence for rotating the rotor toward an angular position next to the initial position. This routing is performed in the desired direction while masking the signals from the one or more rotor position sensors for a preestablished masking time. The step of exciting for fixed time intervals is repeated until verifying that the excited phases are those commanding advancement of the rotor toward the angular check zone, or a change of state of the signals of the one or more rotor position sensors if the masking time has elapsed. The start-up routine further includes associating to each code of the position sensors a new angular check zone to be reached by repeating the sequence of operations starting from step of exciting.

Motor vehicle head lamps that can be adjusted in two directions, uses sensors to monitor operation of head lamps that rotate horizontally with steering to put vertical aim in a safe position if horizontal rotation mechanism fails

Abstract: The head lamps have a drive to displace the lamp (30) in a horizontal arc depending on the direction of the steering. Detectors (203,433) sense anomalies in the displacement of the lamp. If an anomaly is detected the optical axis of adjusted vertically (5) to an angular position lower than a reference angle.

Coordinate measuring system

Abstract: An apparatus and method is utilized to measure relative rigid body motion between two bodies by measuring linear motion in the principal axis and linear motion in an orthogonal axis. From such measurements it is possible to obtain displacement, departure from straightness, and angular displacement from the principal axis of a rigid body.