Abstract: A surveillance system is configured to detect a rotary-wing aircraft approaching a fixed facility and provide a warning upon detection. The system includes acoustic processing nodes that receive acoustic signals from the environment surrounding the fixed facility. As the nodes receive the acoustic signals, the nodes perform a spectral analysis of the signals to detect if the source of the acoustic signals is a rotary-wing aircraft. Additionally, based upon the acoustic signals, the nodes detect an altitude of the rotary-wing aircraft and a distance between the rotary-wing aircraft and the fixed facility. In the case where the system identifies the rotary-wing aircraft as encroaching a predefined geographical area outside of the facility, based upon the altitude and distance between the rotary-wing aircraft and the facility, the system generates a warning to allow security forces to intercept the rotary-wing aircraft prior to its arrival at the facility.

Abstract: The invention is directed to a handsfree system for use in a vehicle comprising a microphone array with at least two microphones and a signal processing means wherein the signal processing means comprises the superdirective beamformer with fixed superdirective filters.

Abstract: Compressive Sensing (CS) is an emerging area which uses a relatively small number of non-traditional samples in the form of randomized projections to reconstruct sparse or com-pressible signals. Direction-of-arrival (DOA) estimation is performed with an array of sensors using CS. Using random projections of the sensor data, along with a full waveform recording on one reference sensor, a sparse angle space scenario can be reconstructed, giving the number of sources and their DOA's. Signal processing algorithms are also developed and described herein for randomly deployable wireless sensor arrays that are severely constrained in communication bandwidth. There is a focus on the acoustic bearing estimation problem and it is shown that when the target bearings are modeled as a sparse vector in the angle space, functions of the low dimensional random projections of the microphone signals can be used to determine multiple source bearings as a solution of an 1]-norm minimization problem.

Abstract: This system has a plurality of microphones oriented in several directions and mounted in a support so that each one is flush with or disposed on a rigid surface, the various microphones being connected to a signal processing device that processes the signals coming from the microphones to provide a noise source hologram, namely a distribution of the acoustic pressures or intensities at various points on a given surface.

Abstract: A method for utilizing a matched field-processing algorithm employing a number of sensors wherein the sensor output is the measured acoustic data as the first input and is translated to a frequency by applying a Fourier transform to a set of time samples as a data vector output. A replica vector is the second data input as a predicted quantity which is computed by an acoustic model with an assumed acoustic location. The output is an ambiguity surface ranging between zero and one with the highest values indicating the likely position of an acoustic location. The matched field response is generalized by averaging the response over multiple frequencies. A response for an array may be computed by forming beams and then combining them by multiplying each by an eigenray factor before summing. The computation of the response may be further defined by voxel interpolation.

Abstract: A mobile unit that moves with a passenger seated thereon includes: an arm rest on which an arm of the passenger is to be placed; and a forward detection sensor that is installed at a distal end portion of the arm rest.

Abstract: The present invention generally relates to an audio signal or gesture detection. More specifically, the invention addresses an apparatus and a method for converting an audio signal detected by microphones or a gesture detected by an image sensing device into a directional indication of the source for the user.

Abstract: A method and system for mapping acoustic sources determined from a phased microphone array. A plurality of microphones are arranged in an optimized grid pattern including a plurality of grid locations thereof. A linear configuration of N equations and N unknowns can be formed by accounting for a reciprocal influence of one or more beamforming characteristics thereof at varying grid locations among the plurality of grid locations. A full-rank equation derived from the linear configuration of N equations and N unknowns can then be iteratively determined. A full-rank can be attained by the solution requirement of the positivity constraint equivalent to the physical assumption of statically independent noise sources at each N location.

Abstract: An on-the-fly method for measuring the length, along an axis (z?z) of an anode (20) used in the production of aluminium by molten salt electrolysis in which: i) said anode is suspended from a gripping member (13a) which is fitted with a displacement sensor measuring the vertical position of the point of attachment (O); ii) said gripping member is moved vertically so that the lower surface (21a) of the anode passes through a plane (P) formed by n beams (f1, . . . , fi, . . . , fn) and, each time one of said beams i (i=1 to n) is disturbed by the lower surface of the anode passing through it, the vertical position hi of said point of attachment (O) is measured; iii) the angle of inclination zz? of the anode stem is measured and the distance between the point of attachment and the lower surface (21a) of the anode block (21) is deduced based on values measured hi (i=1 to n), and the inclination value of the anode stem.

Abstract: An edge detecting apparatus for using in an automatic device and configured for detecting edges of a surface on which the automatic device moves is provided. The edge detecting apparatus includes an emitter, a guiding member, and a receiver. The emitter is configured for emitting projecting signal. The guiding member is around the automatic device. The guiding member and the surface define a signal channel, and the signal channel is configured for guiding the projecting signal to travel around the automatic device, if no edge of the surface exists under the signal channel. The receiver is configured for receiving the projecting signal.

Abstract: There is provided a sonic wave output device comprising, a receiving unit to receive wireless signals transmitted from a certain signal source, a determination unit to determine a parameter value depending on a location of the signal source using the wireless signals received by the receiving unit and a sonic wave output unit to output sonic waves with directionality toward a direction of the signal source based on the parameter value.

Abstract: A MEMS microphone comprising: a) a case with an open front side; b) a MEMS membrane mounted on one face of a base, the base being mounted inside the case on a substantially closed side; and c) a mesh covering the front side, substantially transparent acoustically to at least some of a range of operating frequencies at which the microphone is sensitive.

Abstract: A lateration system comprising at least one transmitter attached to a first object and configured to emit pulses, three or more receivers attached to at least one second object and configured to receive the pulses emitted by the transmitter, and a processor configured to process information received from the three or more receivers, and to generate a vector based on lateration. Lateration is one of multilateration and trilateration. The vector is used by the processor to constrain error growth in a navigation solution.

Abstract: Apparatus configured for processing of both audible and ultrasonic sound inputs, including a sensor with a frequency response spanning both audible and ultrasonic frequencies, and processing electronics configured to separate the audible and ultrasonic input frequencies for independent use. Apparatus configured for processing of both audible and ultrasonic sound inputs, including a sensor with a frequency response spanning both audible and ultrasonic frequencies, and processing electronics configured to process each one of the audible and ultrasonic input frequencies independently. Related apparatus and methods are also described.

Abstract: In a data transfer system in which wireless data transmission is carried out between a first device and a second device that each has a UWB wireless device, the data transfer system includes a ranging unit that is provided in the UWB wireless device of at least one of the first and second devices and measures a distance to the other of the first and second devices; a distance determination unit that determines, based on a measurement result by the ranging unit, whether or not the distance between the first and second devices has been within such a predetermined range that a predetermined transmission rate and a predetermined transmission quality are obtained by UWB communication; and a data transfer unit that executes data transmission between the first and second devices in response to a determination by the distance determination unit that the distance between the first and second devices has been within the predetermined range.

Abstract: The present invention provides a method and system for positioning an object with adaptive resolution. The method comprises: dividing a space to be detected into Hot Area and General Area; arranging, according to the positions of Hot Area and General Area, high-resolution positioning signal (US) transceivers and low-resolution positioning signal (RF) transceivers, wherein the detection scope of the low-resolution positioning signal transceivers covers the space and the detection scope of the high-resolution positioning signal transceivers covers the Hot Area; and when the object moving in the space, fusing the detection results from the high-resolution positioning signal transceivers and the low-resolution positioning signal transceivers to determine the position of the object with adaptive resolution. With the system of the present invention, for different areas, the object can be positioned with different positioning resolutions (precisions or granularities).

Abstract: A mobile communications device contains at least two microphones. One microphone is located away from the handset receiver and serves to pick up voice of a near end user of the device for transmission to the other party during a call. Another microphone is located near the handset receiver and serves to pick up acoustic output of the handset receiver (a far end signal). A signal processor measures the frequency response of the receiver. The signal processor performs spectral analysis of the receiver frequency response to determine whether or not the device is being held at the ear of the user. On that basis, the device automatically changes its operating mode, e.g., turns on or off a touch sensitive display screen during the call. Other embodiments are also described.

Abstract: There is provided a pulse detecting device which resists fluctuations in the quality by locating an ultrasound transmitting piezoelectric element and an ultrasound receiving piezoelectric element with high precision. In the pulse detecting device, a detection sensitivity of the pulse is improved. A transmitting piezoelectric element and a receiving piezoelectric element are fixed onto a substrate by electrodes. The transmitting piezoelectric element is excited in response to an inputted drive voltage signal to generate an ultrasound and transmits the generated ultrasound to a living body. The receiving piezoelectric element receives an echo produced by reflecting the ultrasound transmitted into the living body by a blood flow of the living body and converts it into a voltage signal. A processing arithmetic unit compares the frequency of the ultrasound generated by the transmitting piezoelectric element with that of the echo received in the receiving piezoelectric element to thereby detect a pulse.

Abstract: A transducer assembly including a fan beam transducer having a beam generation axis for generating a fan shaped acoustic beam along the beam generation axis. The fan shaped acoustic beam can have a generally elliptical cross sectional shape with a major axis and a minor axis across a plane generally perpendicular to the beam generation axis. The transducer can be housed in a housing and have a direction of travel axis. The fan shaped acoustic beam can be rotatable relative to the direction of travel axis. The housing can have a release locking arrangement for rotationally releasing and locking the position of the fan shaped acoustic beam for orienting at least one of the major axis and minor axis of the fan shaped acoustic beam at a desired position relative to the direction of travel axis.

Abstract: A method and apparatus for determining the position of an object relative to a moving vehicle. While the vehicle is moving in a first direction, successive sensor pulses are transmitted from a vehicle sensor and toward the object. The echo or reflection from the sensor pulse is then received while a processor determines the transit time between the transmission of each pulse and the receipt of its echo. An angle factor is then calculated which represents the difference between the elapsed time of two sequential sensor pulses and the distance traveled by the vehicle between those two pulses. Whenever the absolute value of the angle factor exceeds a preset threshold, an angle is selected from a predefined lookup table contained in memory. Conversely, when the absolute value of the factor is less than the preset threshold, the angle is calculated as a function of the factor.

Abstract: A diver unit computes the direction and distance to a specified target. When the target is obstructed, the diver unit receives navigation assistance data from another diver unit. The navigation assistance data includes direction information that is referenced to a common reference line extending between the two diver units.

Abstract: Method for locating an impact on a surface (9), in which acoustic sensors (6) pick up acoustic signals ski (t) generated by the impact and the impact is located by calculating, for a number of reference points of index j, a validation parameter representative of a function: PRODkji1i2. . . i2P(?)=?Ski1(?) ?Rji1(?)*?Ski2(?)*?Rji2(?) . . . ?Ski2p(?)*?Rji2p(?) where: ?Ski(?) and ?Rji(?)* are complex phases of Ski(?) and of Rji(?), for i=i1, i2, . . . , i2p, indices denoting sensors, Ski(?) and Rji(?) being the Fourier transform of ski(t) and rji(t), rji(t) being a reference signal corresponding to the sensor i for an impact at the reference point j, p being a non-zero integer no greater than NSENS/2.

Abstract: An ultrasonic distance-measuring sensor assembly and an ultrasonic distance-measuring sensor thereof are disclosed. The ultrasonic distance-measuring sensor includes at least two piezoelectric actuators and a member. The member includes a side wall, at least two vibration generating/receiving surfaces and a partition. The vibration generating/receiving surfaces accommodate the piezoelectric actuators as sources. The side wall surrounds the vibration generating/receiving surfaces. The partition is disposed between the vibration generating/receiving surfaces and includes a gap. The gap is disposed between the vibration sending/receiving surfaces.

Abstract: Signalling and localisation device for an individual in the sea, including an ultrasonic wave transmitter constituting an individual alarm unit carried by the individual in the sea designed to transmit carrier waves of primary signals; a surface surveillance means arranged on the surface of the sea and provided with: a submersed antenna capable of picking up the primary signals transmitted by individual alarm unit; means of transmitting secondary ultrasonic signals, these transmission means: means capable of calculating the position of individual alarm unit as a function of the ultrasonic signals received in response to secondary ultrasonic signals and of converting this information into the coordinates of a global positioning system; a unit for transmitting radio waves capable of sending signals representing these coordinates to a mobile or fixed alarm processing centre equipped with a radio receiver.

Abstract: A sound source detecting device includes a number of sound wave detectors, a voltage comparator, and an analyzer. The sound wave detectors are positioned at different positions, and configured for detecting a sound wave, and each of the detectors produces an electrical signal associated to the sound wave detected by the detector and outputting the electrical signal. The voltage comparator is connected to the detectors and configured for receiving the electrical signals transmitted from the detectors and comparing the voltages of electrical signals to get the highest, second highest, and lowest voltages, then outputs a comparison result. The analyzer is connected to the voltage comparator and configured for identifying the position of a sound source producing the sound wave according to the comparison result transmitted from the voltage comparator and a predetermined principle stored in the analyzer, and then outputs an analyzing result indicating the direction of the sound source.

Abstract: An ultrasonic signal communication device that has an ultrasonic oscillation unit that has at least two resonance frequencies according to the oscillation mode, a transmission unit that generates a first ultrasonic signal at one of the two resonance frequencies and transmits the generated first ultrasonic signal from the ultrasonic oscillation unit, and a reception unit that receives from the ultrasonic oscillation unit a second ultrasonic signal that is transmitted at the other of the two resonance frequencies.

Abstract: A method for functionally testing an ultrasonic sensor on a motor vehicle in which, in a test operating mode, an ultrasonic signal is emitted whose magnitude is large enough that under conventional conditions this ultrasonic signal is reflected by a ground surface in front of the vehicle and is received again. In this way, it can easily be determined that the ultrasonic sensor is functioning properly.

Abstract: Disclosed is a hybrid ranging method comprising the steps of: transmitting from a first node an ultrasonic signal and a radio signal comprising at least one radio synchronization signal with a predetermined ratio; calculating, at a second node, a ultrasonic transmission time period between the receipt of the radio synchronization signal and the receipt of the ultrasonic signal; calculating, at the second node, an ultrasonic measured result between the first node and the second node by using the ultrasonic transmission time period; calculating, at the second node, the strength of the received radio signal, and obtaining a radio measured result between the first node and the second node from a reference database; calculating, at the second node, the smoothness of the ultrasonic measured result and the radio measured result; and determining at the second node, a final measured result according to the smoothness of the ultrasonic measured result and the radio measured result.

Abstract: The present invention provides a method and apparatus for directional de-signature of a seismic signal. The method includes forming a plurality of far-field signatures representative of a plurality of seismic signals having a plurality of take-off angles, associating a plurality of traces representative of a plurality of reflections of the seismic signals with the plurality of far-field signatures, and forming a plurality of de-signatured traces from the plurality of traces and the plurality of associated far-field signatures.

Abstract: A 3D tracking system is provided. The 3D tracking system includes at least one acoustic emission sensor disposed around an object. The acoustic emission sensor is configured to identify location of a probe inserted into the object based upon time of arrival of an acoustic signature emitted from a location on or near the probe. The 3D tracking system also includes a first sensor configured to detect an elevation of the probe. The 3D tracking system further includes a second sensor configured to detect an azimuth of the probe.

Abstract: A system and method for selecting an object from a plurality of objects in a physical environment is disclosed. The method may include analyzing acoustic data received by a plurality of acoustic sensors, detecting a snapping sound in the acoustic data, determining the direction of the snapping sound, estimating the distance to an object based on loudness measurements of the snapping sound detected in the acoustic data, and determining the location of the object relative to the system based at least in part on the determined direction, the estimated distance to the object and the location of the system. The method may further include identifying the selected object based on its geolocation, collecting and merging data about the identified object from a plurality of data sources, and displaying the collected and merged data.

Abstract: A method for tracking motion using an audio compass is disclosed. The method comprises receiving motion sensor data indicating seismic activity recorded by at least two seismic sensors, and converting the received motion sensor data into audio signals for interpretation at an audio compass. The method uses the audio compass to determine a current distance to the seismic activity based on an interpreted signal intensity of the audio signals. The method further uses the audio compass to identify a current position of the audio compass relative to the seismic activity.

Abstract: A method of communicating with an electronic device. The method includes providing an electronic device having an audible sound receiving and generating sub-system including a microphone, transmitting from a source at least one acoustic signal encoded with information, receiving said at least one acoustic signal by said microphone and determining a spatial position, distance or movement of the microphone relative to the source, responsive to the received at least one signal.

Abstract: A method of providing an indication of the direction of a target such as a sniper. A rifle mounted sensor array detects an acoustic pulse originating from the target. The signal is processed to estimate the direction of the target, and an indication is provided when the weapon is aligned with the estimated direction. The direction of arrival of an acoustic pulse is estimated by spectrally decomposing each signal from the sensor so as to generate one or more spectral components for each signal, and processing the spectral components to estimate the direction of arrival.

Abstract: Systems for analyzing acoustic waves are provided. An exemplary system includes a housing, multiple acoustic passageways and an acoustic sensor. The housing defines an interior cavity. The multiple acoustic passageways communicate acoustically between the interior cavity and an exterior of the housing. Each of the acoustic passageways has an inlet port and an outlet port, with each outlet port being located within the housing to direct a portion of an acoustic wave to the interior cavity. The acoustic sensor is mounted within the interior cavity and is operative to receive portions of an acoustic wave directed to the interior cavity by the acoustic passageways. The acoustic sensor also is operative to provide information such as direction of arrival information corresponding to a composite waveform formed by acoustic interference, within the interior cavity, of the portions of the acoustic wave. Methods and other systems also are provided.

Abstract: A system for localizing and positioning towed acoustic linear antennas. In one aspect, a system for localizing and positioning towed acoustic linear antennas includes two or more linear antennas, where each linear antenna has at least one distance measurement device configured to measure the distance to at least one adjacent linear antenna and to transmit signals corresponding to distance measurements. The system further includes one or more navigational control devices along each linear antenna that are configured to control at least the lateral position of each linear antenna. The system also includes one or more controllers distributed over the length of each linear antenna, where each controller is configured to receive distance measurement signals from at least one distance measurement device, process the distance measurement signals, and to control at least one navigational control device according to the processed distance measurement signals. Other aspects are disclosed.

Abstract: An apparatus for range-estimating a noise source including a first passive, vertical hydrophone array of at least two receivers at a first distance from the noise source. The apparatus includes a second passive, vertical hydrophone array of at least two receivers at a second distance from the noise source. The apparatus also includes a processor communicating with the first passive, vertical hydrophone array and the second passive, vertical hydrophone array to determine a ratio of the first distance to the second distance.

Abstract: A method and apparatus for determining the geographic location of a user incorporates the sensing of a plurality of physical environmental parameters at the user's location. The parameter values are compared to corresponding parameter values associated with known locations, and a best-fit correlation is established. The identity of the determined location may be displayed to the user, or may be used to control a location-based operation, such as the unlocking of a safe, the transmission of an entry password, or the disabling of a piece of equipment. Persistence weighting values for different environmental parameters may be applied to improve the reliability of the correlation.

Abstract: The inventive method relates to the field of submarine detection and deals in particular with the problem of detecting low-power acoustic underwater objects by passive detection systems, of the passive drifting buoy type, which are used by maritime patrol systems, for example. The method consists in processing the complex amplitude-azimuth spectrum of an acoustic signal received by a directional buoy. For different target models envisaged, this processing involves associating the complex frequency components of the received signal, located along the time-evolution curve of the frequency of a signal corresponding to a model target, and comparing the modulus and argument variation of these frequency components with the modulus and argument variation over time of the spectral components of the signal corresponding to the model, the processing using both the amplitude and azimuth information contained in the received signal.

Abstract: A device for measuring the radius of curvature of a surface comprises a main body that is held above the surface being measured; and a non-contact sensor mounted to the main body that measures a distance between the surface being measured and the sensor, the device calculating the radius of curvature of the surface based on the measured distance. The device can further include a display mounted to the main body that displays the calculated radius of curvature. The non-contact sensor can be, for example, an acoustical distance sensor or an optical distance sensor. In one embodiment, the device includes two arms extending from the main body of the device and being substantially symmetric about the non-contact sensor, the arms terminating in contact points that make contact with the surface being measured.

Abstract: In order to locate electromagnetic or acoustic signal sources of a sensor configuration (1 a through 1 c) fitted with at least two electric outputs; where the incidence-dependent transfer functions between the acoustic signals incident on the input(s) of the sensor configuration (1 a through 1 c) and the electric output signals are different, the ratio (7X through 7XX) of the output signal is formed and the result then is correlated with the previously determined ratio function (11).

Abstract: A distance and temperature sensing unit is used on paving vehicles. The unit has a first set of range sensors of a first diameter and a second set of range sensors of a second diameter. The unit calculates a weighted average distance to a road surface based on ranges measured by the multiple sensors. The unit also has a temperature sensor on a temperature bar. The bar is affixed to the unit by a flexible connection preventing break-off when the bar encounters obstacles, like the road surface, while the paving vehicle is moving.

Abstract: A communication interface for a path measuring device is provided. The interface can be coupled between the path measuring device and a control device. A path determination can be carried out by the path measuring device by way of a measurement of the propagation time of measurement signals. A measurement of the propagation time can be triggered by way of control signals on a control signal communication channel. A propagation-time signal communication channel is provided for propagation-time signals. The present invention enables a path measuring device to be used universally and in a simple manner, as the communication interface may be coupled to the control signal communication channel and/or to the propagation-time signal communication channel and digital data may be transmittable between the control device and the path measuring device in addition to control signals for the measurement of the propagation time and propagation-time signals.

Abstract: A system and method for detecting, identifying, and fixing the location of the source of an acoustic event. The inventive system includes: a plurality of sensors dispersed at somewhat regular intervals throughout a monitored area; a communication network adapted to deliver information from the sensors to a host processor; and a process within the host processor for determining, from the absolute times of arrival of an event at two or more sensors, a position of the source of the event. Acoustic events are detected and analyzed at each sensor so that the sensor transmits over the network: an identifier for the sensor; an identifier for the type of event; and a precise absolute time of arrival of the event at the sensor. In a preferred embodiment, the system also identifies the type of weapon firing a gunshot.

Abstract: In one aspect, a method to determine multipath angles of arrival includes performing an autocorrelation on a first signal received at a first received beam from a signal source, performing a cross-correlation between the first signal and a second signal received at a second receive beam from the signal source, and determining an angle of arrival for a first path from the signal source and an angle of arrival for a second path from the signal source based on the autocorrelation and the cross-correlation.

Abstract: A fish length measuring apparatus that incorporates a digital scale allows fishermen to both measure and weigh their catch without touching or handling the fish. The apparatus incorporates a housing with a lip grip to grasp the mouth of the fish. A viewable digital output screen is connected to a weight-sensing member whereby the weight of the fish generates a digital numeric display. A distance-measuring sensor projects a beam towards a surface adjacent the tail of the fish and detects the reflection from that surface, then calculates the distance (i.e., length) and displays the length on the output screen. The contour of the housing facilitates hand-holding of the apparatus, and a variety of unique digital data may be selectively displayed on the output screen.

Abstract: Methods and systems for providing an improved geolocation of a plurality of transmitters are disclosed. In one embodiment, a method for providing a geolocation of a plurality of transmitters includes determining a relative location of each transmitter in the plurality of transmitters with respect to at least one other transmitter in the plurality of transmitters; determining an initial geolocation of the plurality of transmitters; computing a calibration factor by comparing the initial geolocation of the plurality of transmitters to the relative locations of the plurality of transmitters; and determining a calibrated geolocation of the plurality transmitters by adjusting at least one final geolocation of the plurality of transmitters by the calibration factor.

Abstract: A system and method for detecting, identifying, and fixing the location of the source of an acoustic event. The inventive system includes: a plurality of sensors dispersed at somewhat regular intervals throughout a monitored area; a communication network adapted to deliver information from the sensors to a host processor; and a process within the host processor for determining, from the absolute times of arrival of an event at two or more sensors, a position of the source of the event. Acoustic events are detected and analyzed at each sensor so that the sensor transmits over the network: an identifier for the sensor; an identifier for the type of event; and a precise absolute time of arrival of the event at the sensor. In a preferred embodiment, the system also identifies the type of weapon firing a gunshot.

Abstract: Tracking a motion of a body by obtaining two types of measurements associated with the motion of the body, one of the types including acoustic measurement. An estimate of either an orientation or a position of the body is updated based on one of the two types of measurement, for example based on inertial measurement. The estimate is then updated based on the other of the two types of measurements, for example based on acoustic ranging. The invention also features determining range measurement to selected reference devices that are fixed in the environment of the body.

Abstract: The lateral position of a web or fabric edge 11 in a paper machine is determined using an ultrasonic sensor. The ultrasonic sensor has a detector head 42, with an air channel system which opens to the vicinity of the head for forming an air knife which prevents accumulation of dirt on the head. The protective cover 35 has an air guide 43 extending further than the detector head 42, with air flowing thereabove from inside the protective cover 35 through an opening 36. The end component is on top of the protective cover allowing air to flow from the opening between the air guide and the end component to a detent, which turns the direction of the air flow. This provides efficient cleaning without disturbing, however, the operation of the ultrasonic sensor.