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EP-4445179-B1 - DIRECTION OF TRAVEL-DEPENDENT SETTING OF A DETECTION AREA OF ULTRASONIC SENSOR ARRAYS

EP4445179B1EP 4445179 B1EP4445179 B1EP 4445179B1EP-4445179-B1

Inventors

  • SCHUMANN, MICHAEL
  • BOECKER, MATTHIAS

Dates

Publication Date
20260513
Application Date
20221117

Claims (5)

  1. Method (20) for adjusting a detection area (E) of at least one ultrasonic sensor array (4) of a vehicle (2) by means of a control unit (8), wherein - measurement data are received and a direction of travel is determined (22), - control signals for controlling at least two transducer elements (6, 7) of the at least one ultrasonic sensor array (4) are generated (24), wherein a phase shift (P) between the ultrasonic waves transmitted by the transducer elements (6, 7) and/or a phase shift (P) between the ultrasonic waves received by the transducer elements (6, 7) is/are set (26) by way of the control signals, said phase shift being adapted to the direction of travel of the vehicle (2), characterized in that , when the vehicle (2) is travelling in a straight line, a detection area (E) of at least one first ultrasonic sensor array (4) is concentrated by a positive phase shift (P) and a detection area (E) of at least one second ultrasonic sensor array (4') is concentrated by a negative phase shift (P) with respect to an axis of symmetry (S) of the vehicle (2) or directed away from the axis of symmetry (S) of the vehicle (2), wherein the axis of symmetry of the vehicle is an axis which is directed in the direction of travel and runs along the longitudinal direction of the vehicle through the centre of the vehicle, in particular between a driver's seat and a front passenger's seat.
  2. Method according to Claim 1, wherein the measurement data for determining the direction of travel are received from a unit (10) configured as a parking assistance system, a steering angle sensor, a GNSS sensor, a trajectory planning system and/or a navigation system.
  3. Method according to Claim 2, wherein a driving path (F) of the vehicle (2) is overlapped by the detection area (E) of at least one ultrasonic sensor array (4) in the direction of travel of the vehicle (2) or a driving path (F) of the vehicle (2) is overlapped by the detection area (E) of at least one ultrasonic sensor array (4) counter to the direction of travel of the vehicle (2).
  4. Method according to one of Claims 1 to 3, wherein the respective phase shift (P) between the generated ultrasonic waves of at least two transducer elements (6, 7) of the respective ultrasonic sensor array which are arranged so as to be offset to each other along a transverse direction (y) and/or along a vertical direction (z) is adjusted by way of the generated control signals, wherein the transducer elements (6, 7) are at a distance from each other in the transverse direction (y) and/or in the vertical direction (z) of at least half a wavelength (lambda) of the generated ultrasonic waves.
  5. Method according to one of Claims 1 to 4, wherein the phase shift (P) of transducer elements (6, 7) of the respective ultrasonic sensor array of the at least two ultrasonic sensor arrays (4) is adjusted by way of the generated control signals such that the detection areas (E) of the at least two ultrasonic sensor arrays (4) overlap in the area of the driving path (F) of the vehicle (2).

Description

The invention relates to a method for adjusting a detection range of at least one ultrasonic sensor array of a vehicle, a control unit, a computer program and a machine-readable storage medium. State of the art Ultrasonic sensors are typically used to monitor the immediate surroundings of a vehicle. These sensors have an optimal range of approximately 5 meters, with each sensor acting as a single source. The beam angle of the sound beam, or the detection range, of common ultrasonic sensors is generally fixed. For reliable ultrasonic distance measurement and object detection, redundant or overlapping measurement of obstacles using multiple ultrasonic sensors is required. However, such overlapping detection ranges of multiple ultrasonic sensors is not possible, particularly when cornering. The US 5,531,117 A This reveals the control of a phase shift in a "phased array" to scatter a resulting ultrasound cone to a desired point. This allows the environment to be scanned. From the DE 10 2005 024 052 A1 Is an ultrasound system known in which the overall viewing angle is controlled based on data from other systems or operating modes, for example depending on the steering angle, can be used. The US 2019/033439 A1 This describes a system for detecting objects and determining distances based on a phased array. An AI controls the system with regard to beam shaping and the phase shift of the phased array's emitters to deflect the detection area. From the US 2019/277962 A1 This describes an arrangement of radar sensors that can be configured as a phased-array sensor. This allows the transmit and receive directions to be adjusted based on a set phase offset. In the DE 10 2014 220994 A1 A driver assistance system is disclosed in which two ultrasonic sensors, each with a fixed detection range, are arranged parallel to each other. The detection ranges of the ultrasonic sensors overlap at their midpoints. Such an arrangement of the ultrasonic sensors and the resulting detection ranges allows a multitude of situations to be correctly detected without requiring any adjustment or swiveling of the detection ranges. Further prior art is disclosed in EP 1 345 044 A1 , DE 10 2010 054066 A1 and from DE 10 2011 079706 A1 known. Disclosure of the invention The object underlying the invention can be seen as proposing a method by which an ultrasound-based measurement can be dynamically adapted to different traffic situations. This problem is solved by means of the respective subject matter of the independent claims. Advantageous embodiments of the invention are the subject matter of dependent claims. According to one aspect of the invention, a method for adjusting the detection range of at least one ultrasonic sensor array of a vehicle is provided. The method can preferably be carried out by a control unit alone or in conjunction with corresponding vehicle-side sensors. In one step, measurement data is received and a direction of travel is determined by evaluating the measurement data. Subsequently, control signals are generated to control at least two transducer elements of at least one ultrasonic sensor array. The control signals are used to set a phase shift between the ultrasonic waves sent by the transducer elements and/or a phase shift between the ultrasonic waves received by the transducer elements, which is adapted to the direction of travel of the vehicle. Advantageously, when the vehicle is traveling straight ahead, the detection area of at least one first ultrasonic sensor array is concentrated by a positive phase shift, and the detection area of at least one second ultrasonic sensor array is concentrated by a negative phase shift relative to or away from the vehicle's axis of symmetry. Using this method, multiple ultrasonic sensor arrays mounted on the vehicle can be controlled by the control signals or commands in such a way that the corresponding sensor arrangement is "squinted," meaning the detection areas of the ultrasonic sensor arrays are rotated or deflected towards the sides of the vehicle. This increases the resulting detection area of all ultrasonic sensor arrays. Alternatively, the detection areas can be concentrated or focused towards the vehicle's axis of symmetry. This reduces the resulting detection range of all ultrasonic sensor arrays. The vehicle's axis of symmetry is defined as an axis directed longitudinally or in the direction of travel, which passes through the vehicle's center, in particular between a driver's seat and a passenger's seat. Furthermore, two operating modes can be implemented when positioning the outer, lateral ultrasonic sensor arrays. Specifically, an operating mode for free maneuvering, also known as PAS mode, and an operating mode for parking space search can be implemented. In the "free maneuvering" mode, an overlap of the detection ranges of as many ultrasonic sensor arrays as possible is achieved. Ultrasonic sensor arrays positioned on the outer sides of the vehicle are rotated to