An ultrasonic type object detection apparatus sequentially detects a distance between an ultrasonic sensor and an object in a coverage of a transmission wave at a predetermined detection cycle based on a time taken for the ultrasonic sensor to transmit the transmission wave and then to receive a reflection wave. The apparatus includes: a storage storing the distance to the object; a vehicle information acquisition device acquiring vehicle information for calculating a movement distance; a detection distance predictor predicting a next detected distance to the object based on a past detection result and the vehicle information; and a short range determinator determining whether the object is present in a short range area in which the distance between the object and the ultrasonic sensor is equal to or shorter than a short range threshold.

An obstacle detection apparatus includes: a transceiver transmitting a transmission wave and receiving an ultrasonic wave; a transmission controller; a receiver circuit detecting a signal level of a receiving wave; a distance calculator sequentially calculating a distance to an object reflecting the transmission wave; a memory storing the distance to the object; an obstacle determination device determining whether the object is an obstacle; and a reception level monitoring device monitoring the signal level of the receiving wave before the transmission wave being transmitted. When the signal level exceeds a predetermined threshold, the obstacle determination device sets a first number of determination data elements to an increased number of determinations for a predetermined period to be used for determining whether the object is the obstacle, as being larger than a second number of determination data elements used when the signal level does not exceed the predetermined threshold.

An obstacle detection apparatus includes: a transceiver transmitting a transmission wave and receiving an ultrasonic wave; a transmission controller; a receiver circuit detecting a signal level of a receiving wave; a distance calculator sequentially calculating a distance to an object reflecting the transmission wave; a memory storing the distance to the object; an obstacle determination device determining whether the object is an obstacle; and a reception level monitoring device monitoring the signal level of the receiving wave before the transmission wave being transmitted. When the signal level exceeds a predetermined threshold, the obstacle determination device sets a first number of determination data elements to an increased number of determinations for a predetermined period to be used for determining whether the object is the obstacle, as being larger than a second number of determination data elements used when the signal level does not exceed the predetermined threshold.

Provided are a sonar system and transducer assembly for producing a 3D image of an underwater environment. The sonar system may include a housing mountable to a watercraft having a transmit transducer that may transmit sonar pulses into the water. The system may include at least one sidescan transducer array in the housing that receives first and second sonar returns with first and second transducer elements and converts the first and second returns into first and second sonar return data. A sonar signal processor may then generate a 3D mesh data using the first and second sonar return data and at least a predetermined distance between the transducer elements. An associated method of using the sonar system is also provided.

A first arithmetic circuit computes a propagation velocity of an ultrasonic wave based on a first time difference between an output timing, at which an ultrasonic element outputs an ultrasonic wave, and a reference timing, at which a comparator circuit outputs a detection signal on reflection off a distal end of a reference pipe, and a length of the reference pipe. A period circuit sets a propagation path detection period to detect a liquid level timing, at which the comparator circuit outputs the detection signal on reflection off the liquid level, based on a longest and shortest propagation path lengths and the propagation velocity. A second arithmetic circuit computes the length of the propagation path based on a second time difference, which is between the liquid level timing and the output timing during the propagation path detection period, and the propagation velocity.

A sensor such as a presence sensor for use in a lighting system or other system that adapts to information from a plurality of active presence sensors. If transmissions from the active sensors are uncoordinated, the overall detection performance may be adversely impacted (e.g. due to potential cross-interference), which may make sensing over the detection coverage area defined by a single presence sensor (or the like) become unreliable. The disclosure presents protocols for coordinating transmissions in active sensing systems. The invention may be applied to various active modalities (e.g. ultrasound, RF), for example that find applications in indoor and outdoor lighting controls.

A sensor such as a presence sensor for use in a lighting system or other system that adapts to information from a plurality of active presence sensors. If transmissions from the active sensors are uncoordinated, the overall detection performance may be adversely impacted (e.g. due to potential cross-interference), which may make sensing over the detection coverage area defined by a single presence sensor (or the like) become unreliable. The disclosure presents protocols for coordinating transmissions in active sensing systems. The invention may be applied to various active modalities (e.g. ultrasound, RF), for example that find applications in indoor and outdoor lighting controls.

A sonar transducer array assembly comprises a first flexible circuit, a second flexible circuit, and a plurality of transducer elements. The first and second flexible circuits each include a first side, a second side, and a plurality of adhesive areas spaced apart and positioned in a line along one edge of the first side. The transducer elements each include a first surface attached to one of the adhesive areas of the first flexible circuit, an opposing second surface attached to one of the adhesive areas of the second flexible circuit, and a third surface positioned between the first and second surfaces. The transducer elements form a linear array with the third surface of each transducer element in alignment and configured to transmit and receive an acoustic pressure wave.

A sonar transducer array assembly comprises a first flexible circuit, a second flexible circuit, and a plurality of transducer elements. The first and second flexible circuits each include a first side, a second side, and a plurality of adhesive areas spaced apart and positioned in a line along one edge of the first side. The transducer elements each include a first surface attached to one of the adhesive areas of the first flexible circuit, an opposing second surface attached to one of the adhesive areas of the second flexible circuit, and a third surface positioned between the first and second surfaces. The transducer elements form a linear array with the third surface of each transducer element in alignment and configured to transmit and receive an acoustic pressure wave.

To provide a driver alert system capable of improving the safety. A bicycle includes a first transmission circuit transmitting a first ultrasonic wave, a first receiving circuit receiving a second ultrasonic wave, an arithmetic circuit detecting the presence or absence of an object from the second ultrasonic wave, and a second transmission circuit transmitting a third ultrasonic wave. A driver wears a second housing including a second receiving circuit receiving the third ultrasonic wave. The arithmetic circuit includes a first selection circuit selecting a potential based on the second ultrasonic wave at a different timing, a plurality of signal retention circuits retaining a potential based on the second ultrasonic wave, a second selection circuit selecting any one of the plurality of signal retention circuits, and a signal processing circuit to which a signal selected in and output from the second selection circuit is input. The second selection circuit selects the plurality of signal retention circuits at different timings to generate a signal obtained by delaying the second ultrasonic wave. The third ultrasonic wave generated on the basis of the signal is transmitted to the second housing.