A method for testing movement speed includes, but is not limited to: measuring a static pressure P.sub.0 of an inner cavity of a pressure hole of a mobile device (S100); aligning the pressure hole to a wind direction and measuring a total pressure P of the wind in a static state (S101); aligning the pressure hole to the wind direction in a moving process, and measuring a pressure P.sub.m of the inner cavity of the pressure hole in a movement direction (S102); obtaining a current wind speed v.sub.f according to a correspondence relationship between a wind speed v.sub.f and a dynamic pressure P-P.sub.0; and obtaining a current relative movement speed v.sub.r according to a correspondence relationship between a relative movement speed v.sub.r and a pressure difference P.sub.m-P.sub.0 (S103); and obtaining a current movement speed v according to the current relative movement speed v.sub.r and the current wind speed v.sub.f (S104).

An apparatus and a method provide an output signal indicative of a speed of rotation and/or a direction of movement of a ferromagnetic object having ferromagnetic features and capable of moving. A variety of signal formats of the output signal are described, each of which have pulses at a rate faster than the ferromagnetic features pass by the magnetic field sensor.

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.

The subject of the present invention is a method for communicating a malfunction of a system for measuring speed and direction of rotation of a rotary shaft, said system comprising: a toothed wheel associated with said rotary shaft, called target (14), a magnetic field sensor (10′), measuring values (K, A) of the magnetic field (B, B′, B″) generated by the passage of the teeth (T1, T2 . . . Ti) in front of said sensor (10′) and delivering a signal (S, S′, S″) to processing means 13). According to the invention, the method comprises the following steps: step 1: comparison by the sensor between the measured values and predetermined threshold values of the magnetic field, step 2: if the measured values are below the predetermined threshold values, step 3: generation by the sensor of a coding on the signal, representative of the measured values, to communicate a malfunction of the system to the processing means.

A method for diagnosing an inversion of a crankshaft sensor includes the following steps: acquiring a signal by way of the crankshaft sensor, at each detection of a tooth, determining a tooth time elapsed since the previous tooth detection, at each detection of a tooth, calculating a ratio Ri of the tooth times according to the formula Ri=(Ti−1).sup.2/(Ti*Ti−2), where Ri is the ratio, Ti is the last tooth time, Ti−1 is the penultimate tooth time, and Ti−2 is the tooth time preceding the penultimate tooth time, comparing the ratio Ri with a low threshold Sb, indicative of a turn marker, and a high threshold Sh, indicative of an absence of inversion, a ratio Ri between the two thresholds Sb, Sh being indicative of an inversion.

The present disclosure provides an ultrasonic wind measurement device and an ultrasonic wind measurement method, so as to measure a wind speed and a wind direction in an environment using transmission characteristics of an ultrasonic wave. The ultrasonic wind measurement device includes: an ultrasonic transducer group configured to generate ultrasonic resonance in a wind measurement cavity receiving the ultrasonic transducer group; a transmission module configured to drive any ultrasonic transducer in the ultrasonic transducer group to transmit an ultrasonic wave; a transmission-reception conversion module configured to perform a link switching operation on the ultrasonic transducer group in accordance with a predetermined control command; a reception module configured to receive the ultrasonic wave; a collection module configured to acquire original data about the transmission and reception of the ultrasonic wave; an FPGA processing chip configured to process the original data so as to acquire time data; and a processor control module configured to acquire a current wind speed and a current wind direction through calculation in accordance with the time data. According to the present disclosure, due to a short ultrasonic transmission distance, it is able to ensure the measurement accuracy. In addition, due to a small volume, it is able to facilitate the installation of the ultrasonic wind measurement device.

A magnetic sensor may include a first sensing element and a second sensing element. The first sensing element may be capable of sensing a first component of a magnetic field that is non-parallel to an axis formed by an intersection of a first plane and a second plane. The first plane may be a plane in which a tooth wheel rotates, and the second plane may include a first surface of the first sensing element and a second surface of the second sensing element. The first component of the magnetic field may be on the second plane. The second sensing element may be capable of sensing a second component of the magnetic field. The second component of the magnetic field may be on the second plane.

In a monitoring apparatus, an optical sensor senses objects present in a sensing area, and moving speeds and moving directions of the objects are calculated based on changes with time in positional information of the sensed objects. An object which meets a predetermined moving condition is determined as a moving object. Hence an entrance of the moving object into the sensing area can be monitored. In this apparatus, by a determining section, it is determined whether or not an object is sensed in an area (after-passage sensing area) which is set to include positions adjacent to positions through which the sensed moving object has passed. When the object has been sensed in the area, by the determining section, it is further determined whether or not the object has remained for a predetermined determination period of time or more. This determined result is outputted by an outputting section.

A sensor device for contactlessly determining a revolution rate and a direction of rotation of a component that rotates during operation of the component, the component having, on at least one peripheral region, a circumferential structure of web-shaped or tooth-shaped radial protrusions and interposed grooves or tooth gaps includes: a threaded segment configured to positionally fix an arrangement of the sensor device so that the circumferential structure of the component is movable past the sensor device; a magnetic field generating device; and a magnetic field detecting device having at least three magnetic field sensors that are not arranged in alignment along a line. A distance between the magnetic field sensors that are the farthest apart from each other is less than or equal to a width of the grooves or tooth gaps of the component.

A first counter is incremented when a first rotational speed sensing device detects a falling edge of one of the teeth of a single multi-tooth target wheel, a second counter is incremented when a second rotational speed sensing device detects a falling edge of one of the teeth, and a third counter is incremented when either of the first and second rotational speed sensing devices detects either of a rising edge and a falling edge of one of the teeth. A direction of rotation is determined based upon the third counter and a rotational speed of the rotatable member is determined based upon one of the first and second counters. The rotatable member is indicated to be at zero speed when the rotational speed is less than a threshold speed and the direction of rotation changes between a positive direction and a negative direction.