Distance-detection system includes a signal-generator configured to provide a drive signal and an ultrasound transducer having at least one ultrasonic element. The ultrasound transducer is configured to transmit a pulse of sound waves and detect reflected sound waves. The distance-detection system also includes a receiver configured to receive a detection signal from the ultrasound transducer. The detection signal includes a reverberation component representing reverberation of the ultrasound transducer and a reflected component representing reflected sound waves from the interface. The receiver is configured to receive a drive-cancellation signal that is inverted with respect to the reverberation component of the detection signal. The receiver is configured to determine a time-of-flight measurement based on the detection signal in which the reverberation component of the detection signal is reduced by the drive-cancellation signal.

An ultrasonic sensor transmits an ultrasonic wave, and receives the ultrasonic wave reflected by an obstacle. An electrical characteristic measuring means measures the electrical characteristic of the ultrasonic sensor, and outputs electrical characteristic information. An environmental state determining means receives the electrical characteristic information from the electrical characteristic measuring means, and outputs environmental information on at least one of the temperature and humidity of the ultrasonic sensor.

An ultrasonic sensing system includes: an amplifier including an input and an output; and an n-level comparator, coupled to the output of the amplifier, to compare an adjustable threshold voltage to an output signal from the output of the amplifier. N is greater than or equal to 1. The system also includes a noise power estimator, coupled to an output of the n-level comparator, to generate a noise power signal indicative of noise power of an input signal at the input of the amplifier. The system further includes a time-varying threshold circuit, coupled to the noise power estimator and the n-level comparator, to adjust the adjustable threshold voltage based on the noise power signal.

A wideband sonar receiver is provided that includes: a selectable bandpass filter adapted to filter a received sonar signal to produce a filtered signal and a correlator adapted to correlate the baseband samples with baseband replica samples to provide a correlated signal. In addition, the wideband sonar receiver may include a shaping filter to shape unshaped received pulses. Finally, a variety of sonar processing algorithms are described with regard to reducing clutter and interference, target detection, and bottom detection.

Techniques are disclosed for systems and methods to provide dynamic threshold sonar systems for mobile structures. A dynamic threshold sonar system may include sonar equipment configured to capturing sonar data by receiving and converting acoustic returns into arrays of time differentiated sonar data samples, and a processor communicatively coupled to the sonar receiver. The processor may be configured to receive the sonar data samples and determine noise characteristics of the sonar data. The processor may determine a threshold for surface detection based on the noise characteristics and detect a surface, and determine a distance to the surface, based on a comparison of the sonar data to the threshold that has been determined based on the same sonar data.

An object detection apparatus is provided with a distance measurement sensor that measures a distance to an object which exists in a surrounding area of a vehicle, by transmitting scanning waves to the surrounding of the vehicle and receiving reflection waves of the scanning waves, and an image acquiring section that is adopted to the vehicle, and is provided with an on-vehicle camera that captures images in the surrounding of the vehicle, the imaging acquiring section acquiring an image that is captured by the camera. The apparatus includes a determination section that determines whether, a predetermined object that is difficult to detect by the reflection waves of the distance measurement sensor is included in the object image, and a sensitivity control section that increases a sensitivity of the object detection by the distance measurement sensor and a vehicle control that is executed relative to the predetermined object as a target object.

A detection device includes: a first correlation circuit that computes correlation of a first wave detection signal, which is a phase-modulated input wave detected at determined frequency, with a determined code sequence for every code composing the determined code sequence, and to generate first correlation signals the number of which corresponds to a code sequence length, which is a length of the determined code sequence; and a control circuit that rotates phases of the first correlation signals, generates an added value by adding the phase-rotated first correlation signals, and determines based on the added value whether the phase-modulated input wave is a return wave from a determined object.

A robotic device comprising a long-range sonar assembly configured to detect objects between 1000 mm to 9500 mm from the long range sonar assembly. The long-range sonar assembly comprises a flared bell housing and a transducer. The robotic device also comprises a transportation mechanism configured to move the robotic device in various directions in response to instructions from a processing device that is in communication with the ling-range sonar assembly and the transportation mechanism. The processing device may cause the long-range sonar assembly to, via the transducer transmit one or more pulses and receive the one or more pulses as echo pulses having reflected off an object in an environment. The processing device may then cause a transmitter to transmit instructions to the transportation mechanism to move the robotic device in the environment based on the received one or more pulses.

An object detection device includes a transmitter to generate an acoustic wave as a signal wave based on a predetermined transmission signal and transmit the signal wave toward an object, a receiver provided separately from the transmitter and to receive the acoustic wave to generate a reception signal, and a controller to generate the transmission signal to control the signal wave from the transmitter. The receiver has frequency characteristics such that the reception signal fluctuates when the receiver resonates. The transmission signal is set according to the frequency characteristics of the receiver to reduce or prevent a resonance of the receiver at a time of reception of the signal wave from the transmitter.

A long-range sonar assembly for detecting objects approximately 2.5-9.5 meters from a robotic device. The assembly includes a printed circuit board including a local controller operably connected to a processing device and configured to receive instructions from the processing device, a transmit potentiometer operably connected to the local controller and configured to produce a first transmit frequency, and a receive potentiometer operably connected to the local controller and configured to produce a first receive sensitivity; a transducer operably connected to the receive potentiometer; and a flared bell configured to house the transducer and the printed circuit board, the flared bell comprising at least a first enclosure for receiving a sub-assembly comprising the printed circuit board and the transducer.