An ultrasonic device according to an aspect of the present disclosure includes a substrate in which an opening section piercing through the substrate in a thickness direction is provided, a vibration plate provided on the substrate to close the opening section, a piezoelectric element provided in a position corresponding to the opening section on a first surface at the opposite side of the substrate side of the vibration plate, and an elastic layer provided in contact with a second surface at the substrate side of the vibration plate at the inner side of the opening section of the substrate. The elastic layer includes a curved surface recessed to the vibration plate side at the opposite side of the vibration plate side.

An ultrasonic device according to an aspect of the present disclosure includes a substrate in which an opening section piercing through the substrate in a thickness direction is provided, a vibration plate provided on the substrate to close the opening section, a piezoelectric element provided in a position corresponding to the opening section on a first surface at the opposite side of the substrate side of the vibration plate, and an elastic layer provided in contact with a second surface at the substrate side of the vibration plate at the inner side of the opening section of the substrate. The elastic layer includes a curved surface recessed to the vibration plate side at the opposite side of the vibration plate side.

A method for switching a screen state, a terminal, and computer-readable medium are provided. The method includes: transmitting a transmission sound wave when it is detected that the screen state of the terminal is in a light-on state during a voice communication session, the transmission sound wave being a sound wave of a pre-defined frequency; determining a target detection region when a target receiving sound wave is received through a plurality of pre-installed sound wave receiving devices, the target receiving sound wave being formed by reflecting the transmission sound wave by a target object; and switching the screen state of the terminal from the light-on state into a light-off state when it is determined that the target object is located in the target detection region.

The present invention discloses a ship draught detection apparatus and its detection method. The ship draught detection apparatus includes two servo motors, a guide rail, a sonar detection device, a traction device, a locating device, and a control device. Compared with the provision of a series of sonar detection devices in the prior art, the provision of one sonar detection device reduces the cost and there is no mutual interference between adjacent sonars. Meanwhile, because a lock gate width of a ship lock is greater than a width of the ship, in order to improve the detection precision, the locating device is configured to predict in advance an accurate position of the ship when passing the ship lock according to the position of the ship and the orientation of a ship bow, and the control device controls the rotation speed and the direction of the two servo motors, and makes the sonar detection device move along the guide rail through the ropes, so that the sonar detection device is located just below the ship when the ship passes the ship lock, thereby improving the detection precision.

The present invention discloses a ship draught detection apparatus and its detection method. The ship draught detection apparatus includes two servo motors, a guide rail, a sonar detection device, a traction device, a locating device, and a control device. Compared with the provision of a series of sonar detection devices in the prior art, the provision of one sonar detection device reduces the cost and there is no mutual interference between adjacent sonars. Meanwhile, because a lock gate width of a ship lock is greater than a width of the ship, in order to improve the detection precision, the locating device is configured to predict in advance an accurate position of the ship when passing the ship lock according to the position of the ship and the orientation of a ship bow, and the control device controls the rotation speed and the direction of the two servo motors, and makes the sonar detection device move along the guide rail through the ropes, so that the sonar detection device is located just below the ship when the ship passes the ship lock, thereby improving the detection precision.

An acoustic-based Direction of Arrival (DoA) system uses acoustic information to determine the direction of incoming sound, such as a person talking. The direction of the sound is then used to focus a laser-based time of flight (ToF) system to narrow the area of laser illumination, improving the signal to noise ratio because laser illumination is focused on the direction of the sound. The DoA system also provides elevation information pertaining to the source of the sound, to further narrow the required field of view of the laser ToF system.

An acoustic-based Direction of Arrival (DoA) system uses acoustic information to determine the direction of incoming sound, such as a person talking. The direction of the sound is then used to focus a laser-based time of flight (ToF) system to narrow the area of laser illumination, improving the signal to noise ratio because laser illumination is focused on the direction of the sound. The DoA system also provides elevation information pertaining to the source of the sound, to further narrow the required field of view of the laser ToF system.

The angle of a trailer with respect to a tow vehicle is an important parameter to the stability of the vehicle and trailer. A tow vehicle pulling a trailer in a straight line is generally more stable than when the vehicle is turning. While turning, the angle between the tow vehicle and the trailer is not a straight line but is another angle depending on how sharply the tow vehicle is turning. To safely operate a vehicle towing a trailer, for a given steering input and speed, there is a maximum angle between the tow vehicle and trailer whereby exceeding the angle causes instability and may cause the trailer or tow vehicle to roll over or jackknife. Accordingly, the angle between the trailer and tow vehicle must be determined to ensure the vehicle and trailer will continue to be in control.

The angle of a trailer with respect to a tow vehicle is an important parameter to the stability of the vehicle and trailer. A tow vehicle pulling a trailer in a straight line is generally more stable than when the vehicle is turning. While turning, the angle between the tow vehicle and the trailer is not a straight line but is another angle depending on how sharply the tow vehicle is turning. To safely operate a vehicle towing a trailer, for a given steering input and speed, there is a maximum angle between the tow vehicle and trailer whereby exceeding the angle causes instability and may cause the trailer or tow vehicle to roll over or jackknife. Accordingly, the angle between the trailer and tow vehicle must be determined to ensure the vehicle and trailer will continue to be in control.

A position detection system using a sensor, including a sensor unit including a plurality of sensors for transmitting a transmission signal or receiving a reflection signal reflected from an obstacle and configured to acquire a time of flight (TOF) of the received reflection signal, a storage unit configured to pre-store a position map of the obstacle for respective sensors depending on the TOF of the reflection signal on a grid map including a plurality of cells, and a position estimator configured to estimate a position of the obstacle based on the TOF of the reflection signal received by the sensor unit and the position map of the obstacle pre-stored in the storage unit.