Systems and methods for calculating a plant spread and a plant density of vegetation are provided. An ultrasonic signal is transmitted towards vegetation by one or more transducers. A plurality of echo signals is received as reflections of the ultrasonic signal by the one or more transducers. A plant spread of the vegetation is calculated based on a first echo signal of the plurality of echo signals and a last echo signal of the plurality of echo signals. A plant density of the vegetation is calculated based on the plurality of echo signals. The plant spread and the plant density of the vegetation are output.

Systems and methods for calculating a plant spread and a plant density of vegetation are provided. An ultrasonic signal is transmitted towards vegetation by one or more transducers. A plurality of echo signals is received as reflections of the ultrasonic signal by the one or more transducers. A plant spread of the vegetation is calculated based on a first echo signal of the plurality of echo signals and a last echo signal of the plurality of echo signals. A plant density of the vegetation is calculated based on the plurality of echo signals. The plant spread and the plant density of the vegetation are output.

A method of providing a collision avoiding travel path for an autonomous vehicle. A sensor system obtains stereo image data of a scene in the environment ahead of the normal travel path. This image data is used to generate a disparity image. The disparity image is processed to generate an occupancy map that assigns values to areas of the scene based on levels of visual clutter. The occupancy map is then converted to a potential field, which assigns each pixel in the scene with a force value that corresponds to its proximity to one or more obstacles. These force value are summed and used to modify the vehicle's path is a collision is likely.

A method of providing a collision avoiding travel path for an autonomous vehicle. A sensor system obtains stereo image data of a scene in the environment ahead of the normal travel path. This image data is used to generate a disparity image. The disparity image is processed to generate an occupancy map that assigns values to areas of the scene based on levels of visual clutter. The occupancy map is then converted to a potential field, which assigns each pixel in the scene with a force value that corresponds to its proximity to one or more obstacles. These force value are summed and used to modify the vehicle's path is a collision is likely.

A method for recognizing a parking space for a vehicle and a parking assistance system are disclosed. An obstacle is identified from successive image frames captured when the vehicle is moving and a first boundary for the obstacle is generated by a Convolutional Neural Network (CNN) algorithm based on a position of the obstacle shown in each of the successive image frames. Distances between the moving vehicle and the obstacle are detected by ultrasonic sensors. A second boundary for the obstacle is generated by a distance modification module based on the distances between the vehicle and the obstacle. A periphery of the obstacle is defined by a periphery definition module. In view of the periphery of the obstacle, a parking space is thus recognized by a parking space recognition module. The parking process can be changed to a self-drive mode, and remotely controlled by a mobile device.

A method for determining the elevation angle and/or azimuth angle of a signal received by an ultrasound sensor includes: providing an ultrasound sensor with a frequency-dependent radiation pattern; transmitting a first ultrasound wave at a first frequency; transmitting a second ultrasound wave at a second frequency different from the first frequency; receiving reflections of the first and second waves, the reflections being caused by an object; and determining the elevation angle of the first and second reflected waves based on amplitudes of the reflections of the first and second waves. Determining the elevation angle (and/or azimuth angle includes calculating a ratio between the amplitudes of received reflections of the first and second waves and mapping a calculated ratio to an elevation angle and/or azimuth angle. The mapping is based on a predetermined ratio curve or ratio dataset which associates a certain amplitude ratio to an elevation angle and/or azimuth angle.

The invention relates to a method for establishing the presence of a misalignment of at least one sensor within a sensor group with two or more sensors which detects objects in the surroundings of a motor vehicle, wherein at least two of the sensors differ from each other in their measuring principle and the measurement signals from the sensors are compared with each other.

Techniques and apparatuses are described that implement face authentication anti-spoofing using ultrasound. In particular, a face-authentication system uses ultrasound to distinguish between a real human face and a presentation attack that uses instruments to present a version of a human face. The face-authentication system includes or communicates with an ultrasonic sensor, which can detect a presentation attack and notify the face-authentication system. In general, the ultrasonic sensor analyzes characteristics of a presented object and determines whether the object represents a human face or a presentation attack instrument. In this way, the ultrasonic sensor can prevent unauthorized actors from using the presentation attack to gain access to a user's account or information.

Techniques and apparatuses are described that implement face authentication anti-spoofing using interferometry-based coherence. In particular, a face-authentication system uses ultrasound to distinguish between a real human face and a presentation attack that uses instruments to present a version of a human face. The face-authentication system includes or communicates with an ultrasonic sensor, which can detect a presentation attack and notify the face-authentication system. In general, the ultrasonic sensor uses interferometry to evaluate an amount of coherence (or similarity) between reflections observed by two or more transducers. In this way, the ultrasonic sensor can prevent unauthorized actors from using the presentation attack to gain access to a user's account or information.

Techniques and apparatuses are described that implement face authentication anti-spoofing using ultrasound. In particular, a face-authentication system uses ultrasound to distinguish between a real human face and a presentation attack that uses instruments to present a version of a human face. The face-authentication system includes or communicates with an ultrasonic sensor, which can detect a presentation attack and notify the face-authentication system. In general, the ultrasonic sensor uses power-spectra to evaluate an amount of variance observed over time within at least one receive channel. In this way, the ultrasonic sensor can prevent unauthorized actors from using the presentation attack to gain access to a user's account or information.