Various embodiments of the teachings herein include a method for determining a target position of a surroundings sensor of a vehicle using a vehicle-side attachment element as a calibration object, wherein the sensor and the attachment element are movable relative to each other. The method includes: ascertaining a first position of the surroundings sensor in a first relative pose; moving the sensor and/or the element from the first pose to a second pose between the sensor and the element; ascertaining a second actual position of the surroundings sensor in the second relative pose; and determining the target position of the surroundings sensor by averaging the first position and the second position to form an averaged actual position and assigning the averaged actual position as the target position.

Provided are a system and a method for measuring a liquid level of a vehicle fuel tank, and more particularly, to a system for measuring a liquid level of a vehicle fuel tank including an ultrasonic sensor unit provided on a bottom surface in the vehicle fuel tank to acquire measurement data for calculating a distance from the bottom surface in the fuel tank to a fuel surface and a central processing unit using the measurement data transmitted from the ultrasonic sensor unit by a preset number of times for a preset time to calculate liquid level information of the fuel tank.

A measuring device for measuring a hole in the ground having at least one measuring probe having at least one measurement signal transmitter to transmit a measurement signal, at least one measurement signal receiver to receive the measurement signal reflected on a wall area of the hole, and an evaluation unit for determining a wall distance between the measurement signal transmitter and the wall area of the hole, wherein a measuring distance based on an assignment rule can be assigned to the received, reflected measurement signal. A calibrating device having at least one calibration element. The measurement signal transmitter transmits a calibration signal, which can be reflected on the calibration element, wherein the measurement signal receiver receives the calibration signal reflected on the calibration element. The evaluation unit changes and calibrates the assignment rule based on the calibration signal reflected and received by the calibration element.

A sensor and a method for detecting a position of the sensor relative to a guide surface, comprising a housing and an electronic analysis device which outputs measurement values for the position of the guide surface on the basis of the measurement signals. The sensor contains an ultrasonic transducer array, each of the two outer ends of which is additionally equipped with a respective reference ultrasonic transducer and a respective reflector surface flush with the reference piezo disc at a distance from the base side, said ultrasonic transducers and reflector surfaces being inclined by 45° relative to the base side and pointing towards one another, thus forming a reference measurement path with a known length between the two reference ultrasonic transducers. In the method for detecting the relative position, the measurement values are corrected with respect to environmental influences by measurements in a reference path.

The invention is a system that enables passive sonar identification of underwater items by making use of lift bags and/or flags, having distinctive sequences of bands of sonar-signal-reflecting materials, wherein the lift items are partially inflated so as to present a predictable orientation with respect to the floor of a body of water and its surface.

It is proposed a method for determining a quantity of a liquid in a tank, the tank comprising: a first ultrasound subsystem capable of measuring level of liquid present above a predetermined threshold level within the tank; and at least one second ultrasound subsystem, said second ultrasound subsystem being associated with a sensing area within the tank and being configured to measure a parameter characteristic of the liquid, said sensing area being located below the predetermined threshold level. The method comprises in the steps of: —checking the validity of the measurement performed by said first ultrasound subsystem (S10); —when it is detected that the measurement of said first ultrasound system is not valid: (a) checking (S22) the validity of the measurement performed by said second ultrasound subsystem; (b) determining (S24, S25, S26) a quantity of liquid, which quantity being based on a result of the validity check at step (a).

The invention is a system that enables passive sonar identification of underwater items by making use of lift bags and/or flags, having distinctive sequences of bands of sonar-signal-reflecting materials, wherein the lift items are partially inflated so as to present a predictable orientation with respect to the floor of a body of water and its surface.

The invention is a system that enables passive sonar identification of underwater items by making use of lift bags and/or flags, having distinctive sequences of bands of sonar-signal-reflecting materials, wherein the lift items are partially inflated so as to present a predictable orientation with respect to the floor of a body of water and its surface.

It is proposed a method for determining a quantity of a liquid in a tank, the tank comprising: a first ultrasound subsystem capable of measuring level of liquid present above a predetermined threshold level within the tank; and at least one second ultrasound subsystem, said second ultrasound subsystem being associated with a sensing area within the tank and being configured to measure a parameter characteristic of the liquid, said sensing area being located below the predetermined threshold level. The method comprises in the steps of: checking the validity of the measurement performed by said first ultrasound subsystem (S10); when it is detected that the measurement of said first ultrasound system is not valid: (a) checking (S22) the validity of the measurement performed by said second ultrasound subsystem; (b) determining (S24, S25, S26) a quantity of liquid, which quantity being based on a result of the validity check at step (a).

A system has an actuator with a first surface and a second surface, the first surface being offset a step dimension from the second surface. A sensor is configured to measure a distance between the sensor and both the first surface and the second surface via a signal received by the sensor after having reflected off the first surface or the second surface. The step dimension is greater than a minimum dimension, which is defined in view of a medium through which the actuator moves and a frequency of the signal.