There is provided an electromagnetic inductive encoder that allows reduction in the number of tracks on a scale for reduction in the size of the scale. The electromagnetic inductive encoder includes a scale having a scale pattern, a head, and computation unit. The head includes transmission unit, which includes transmission coils, and reception unit, which includes reception coils. The scale pattern has a first pattern, which causes the reception coils to receive positive current, and a second pattern, which causes the reception coils to receive negative current. The computation unit includes a determination unit, which, when the positive current is detected, determines that the current is associated with the first pattern, and, when the negative current is detected, determines that the current is associated with the second pattern, a signal generation unit, which generates a signal formed of 1 representing the first pattern and 0 representing the second pattern based on the result of the determination, and a position calculation unit, which calculates the position of the head based on the signal generated by the signal generation unit.

Wireless transmission of wheel rotation direction is disclosed. A disclosed apparatus includes a tone ring exhibiting a rotational asymmetry and a detector to measure a rotational direction of a wheel of a vehicle based on the rotational asymmetry and to measure a rotational speed of the wheel, where the detector or the tone ring is operatively coupled to the wheel. The disclosed apparatus also includes a wireless transmitter to transmit the rotational direction and the rotational speed to a receiver proximate or within an engine compartment of the vehicle.

An absolute encoder is driven by backup power from an external battery for backup. The absolute encoder includes: a clock generator configured to generate backup clock pulses at intervals of a predetermined period when the backup power is supplied; an analog signal generation circuit configured to operate according to the clock pulse so as to detect a displacement position of a motor and generate an analog signal corresponding to the detected displacement position; a comparator configured to operate according to the clock pulse so as to compare the analog signal with a predetermined voltage; and a clock control circuit configured to control the clock generator to change the pulse width of the clock pulse.

An absolute encoder that receives a current from an electronic power supply includes: a plurality of regulators connected in parallel with one another that receive a drive current from an electronic power supply in which a magnitude of a constant voltage output to the absolute encoder and a magnitude of a drive current needed for outputting the constant voltage are different; a voltage detection unit configured to detect an output voltage of at least one regulator of the plurality of regulators; and an abnormality detection unit for detecting an abnormality of a current from an electronic power supply consumed when the absolute encoder is driven based on the output voltage detected by the voltage detection unit.

An inductive sensor device (23) having a scale unit (24) and a sensor unit (25) that can be moved relative to each other in a measuring direction (M) is described. The scale unit contains scale elements (26) that are adapted to create a field pattern (P(x)) in measuring direction (M) that is detected by means of a receive circuit (35) of the sensor unit (25). The receive circuit (35) contains at least a first receive coil set (36) and a second receive coil set (37) that are offset in measuring direction (M). In so doing a first spatial phase and a second spatial phase receive signal is provided by these receive coil sets (36, 37) respectively. These spatial phases can be used for absolute position determination.

A drug delivery device comprising; a housing; a cylindrical member configured to be rotatably supported inside the housing, wherein the outer surface of the cylindrical member is provided with at least first and second tracks together forming an encoder, each track comprising conductive segments and non-conductive segments; and at least first and second groups of contacts configured to engage the first and second tracks respectively at predetermined intervals along the length of the track.

A method of correcting a position reading from a position sensing arrangement. The position sensing arrangement is suitable for sensing the position of a revolute joint of an articulated structure, and comprises a disc having a magnetic ring with magnetic pole pairs and a magnetic sensor assembly comprising a magnetic sensor array for detecting the magnetic pole pairs of the magnetic ring. The method comprises: for each pole pair of the magnetic ring, taking a calibration pole pair position reading with the magnetic sensor array, and generating a pole pair correcting function by comparing the calibration pole pair position reading with a model pole pair position reading; averaging the pole pair correcting functions of the pole pairs of the magnetic ring to generate an average pole pair correcting function for the magnetic ring; taking a position reading with the magnetic sensor array, the position reading comprising a plurality of pole pair position readings; and generating a corrected position reading by deducting the average pole pair correcting function from each pole pair position reading.

The present disclosure provides an absolute encoder capable of suppressing an increase in size while securing the resolution. An encoder includes a magnet rotating integrally with at least one rotary body and a plurality of rotary sensors detecting magnetic poles of the magnet to output detection signals having sinusoidal waveforms, each sinusoidal waveform having a different phase. The at least one rotary body includes a first rotary body rotating integrally with a main shaft and a third rotary body rotating together with the rotation of the first rotary body. The absolute encoder includes an angular sensor to detect the rotational angle of the first rotary body and the magnet is arranged in the third rotary body.

A sensor is provided for determining at least one rotation characteristic of a rotating element. The sensor includes a sensor wheel, which is connectable to the rotating element, including at least one first reading track. The reading track includes a first plurality of magnetic event timers. The sensor furthermore includes at least one magnetic sensor for detecting magnetic events generated by the first plurality of magnetic event timers. The first reading track is designed in such a way that, over a complete circumference of the sensor wheel, a magnetic field strength of the first plurality of event timers changes step-by-step from a first maximum north pole to a first maximum south pole.

A method of assembling a position sensing arrangement for sensing the position of a revolute joint of an articulated structure. The position sensing arrangement comprises a magnetic sensor assembly and a disc having a first magnetic ring with j magnetic pole pairs and a second magnetic ring with k magnetic pole pairs. A boundary of the disc is constrained by the articulated structure. The method comprises: determining a number of pole pairs of the first magnetic ring to be an integer p such that the first magnetic ring is separated from the constrained boundary by at least the magnetic sensor assembly; determining a number of pole pairs of the second magnetic ring to be an integer q such that the second magnetic ring is separated from the first magnetic ring by a predetermined distance; and if p and q are co-prime: selecting j to be p and k to be q; and assembling the position sensing arrangement by mounting the disc to the articulated structure such that both the disc and the revolute joint are permitted to rotate about the same axis.