Sensor unit for determining an orientation of the sensor unit

Abstract

The present invention relates to a sensor unit (10) for determining an orientation (12) of the sensor unit (10), comprising: a printed circuit board unit (14), at least two sensor elements (16), wherein the at least two sensor elements (16) are arranged on the printed circuit board unit (14), wherein the at least two sensor elements (16) are designed to emit and / or receive at least a first ultrasonic wave, wherein the sensor unit (10) is designed to determine the orientation (12) of the sensor unit (10) to a reference (18) of a vehicle (100) by adapting the first emitted ultrasonic wave by means of the at least two sensor elements (16).

Description

Prior ArtThe present invention relates to a sensor unit for determining an orientation of the sensor unit, and to a vehicle.At present, there are a large number of different solutions for determining alignments of sensors in the ultrasonic range. As a result of the increasing number of ultrasonic sensors in the vehicle sector and the increased quality requirements, the need for innovative and robust ultrasonic measurement systems is continually increasing.The constant weight reduction in the vehicle sector for reducing consumption and the increasing competition ensures cost pressure, so that favorable and efficient components for vehicles are more demanded.Disclosure of the InventionThe sensor unit according to the invention for determining an orientation of the sensor unit having the features of claim 1 has the advantage over the known art that by determining the orientation of the sensor unit with respect to a reference of the vehicle, a correct installation and positioning of the individual ultrasonic sensor unit and the positioning thereof in the ultrasonic sensor system can be checked. A further advantage is that by referencing a plurality of ultrasonic sensor units to one another, statistical models can be used in order to be able to check the correct installation of the sensor unit.This is achieved according to the invention in that the sensor unit has a printed circuit board unit and at least two sensor elements for ascertaining an orientation of the sensor unit. The at least two sensor elements are arranged on the printed circuit board unit, wherein the at least two sensor elements are configured to emit and / or receive at least one first ultrasonic wave, wherein the sensor unit is configured to determine the orientation of the sensor unit with respect to a reference of a vehicle by adjusting the first emitted ultrasonic wave by means of the at least two sensor elements.In other words, by using the beam steering capability of a MEMS ultrasonic sensor array in a defined measurement process, the wavefront can be directed at defined angular settings on the ground, such that the reflected wave can be received at the same ultrasonic array in order to be able to determine the orientation of the vehicle. For example, the sensor unit can be a MEMS-based ultrasonic sensor. The sensor unit may preferably have a multiplicity of sensor elements, which may be, for example, an ultrasonic array having an orientation of 2 x 2 sensor elements. Further preferably, a plurality of printed circuit board units can also be provided on a vehicle, each of which comprises a plurality of sensor elements. The reference of the vehicle can be in particular a coordinate system or the like, such as in accordance with DIN 70000, for example. It can thus be determined whether or not the sensor unit has been installed in the vehicle in the orientation or positioning provided for this purpose in the vehicle. Further preferably, deformations of the bumper in which the sensor unit can be installed can likewise be determined after an accident or not proper installation, since the orientation of the sensor unit deviates from the predetermined orientation. Preferably, in particular, the orientation of the sensor units to a predetermined orientation can be determined, and if this deviates by a predetermined value, a signal is output by the sensor unit.The dependent claims show preferred developments of the invention.The at least two sensor elements are preferably configured to emit at least one second ultrasonic wave, wherein the sensor unit is configured to adjust a phase offset between the first ultrasonic wave and the second ultrasonic wave in order to determine the orientation of the sensor unit.An advantage of this embodiment is that the detection accuracy of the orientation of the sensor unit with respect to the reference of the vehicle can be further improved with the aid of the second ultrasonic wave. The two sensor elements can preferably emit a plurality of ultrasonic waves, which can be used to determine the orientation of the sensor unit by adjusting the phase offset with respect to one another.Further preferably, the sensor unit is configured to adapt the phase offset such that a first maximum of the first ultrasonic wave and / or a second maximum of the second ultrasonic wave move along a first axis and / or a second axis.An advantage of this embodiment is that different reflection surfaces can be selected with the aid of the sensor unit in order to be able to determine the orientation of the sensor unit. For example, by adjusting the phase offset, the maximum of the wavefront can be changed upwards or downwards as well as to the left and to the right starting from the sensor unit. For example, in particular the first axis can be aligned orthogonally to a placement surface of a vehicle and / or the second axis can be aligned substantially orthogonally to the first axis.The sensor unit is preferably configured to emit the first ultrasonic wave on the basis of a predetermined orientation, wherein the sensor unit is configured to compare the transit time of the first ultrasonic wave at the predetermined orientation with a predetermined reference value in order to determine the orientation of the sensor unit.On the basis of the expected distribution of the temporal offset at the predefined orientation or angle of incidence, it is possible to validate whether the ultrasound system has been correctly installed.Further preferably, the sensor unit is configured to receive an initiation signal, wherein the sensor unit is configured to determine the orientation of the sensor unit if the initiation signal is present.An advantage of this embodiment is that a central unit, such as a control device of a vehicle, can trigger the determination of the orientation of the sensor unit. In this case, in particular, the control device of the vehicle can check whether all sensor units are available for the control device in order to subsequently be able to determine all orientations of the sensor units and to be able to compare them with one another.The sensor unit is preferably configured to receive a temperature value and / or a geographical position, wherein the sensor unit is configured to adapt the orientation of the sensor unit on the basis of the temperature value and / or the geographical position.An advantage of this embodiment is that the speed of sound changes on the basis of, for example, the altitude or the air pressure, and the determination of the orientation is improved or can be adapted on the basis of the ambient temperature and the GPS coordinates or geographical position.A further aspect of the invention relates to a vehicle which has a first sensor unit as described above and below, wherein the first sensor unit is configured to emit at least one first ultrasonic wave, wherein the first sensor unit is configured to determine a first orientation of the first sensor unit with respect to a reference of the vehicle by adjusting the first emitted ultrasonic wave.For example, the vehicle may have a parking sensor such as an ultrasonic parking sensor or the like. The ultrasonic parking sensors are preferably arranged in the front and rear region of the vehicle. Thus, in particular, the first sensor unit of the vehicle can be aligned such that it can monitor a floor area in the vehicle front or rear area. By means of one of the first transmitted ultrasonic waves, the sensor unit can determine and / or determine an orientation of the first sensor unit with respect to the reference of the vehicle, so that a correct installation position of the sensor unit can be checked.Further preferably, the vehicle has a second sensor unit, as described above and below, wherein the second sensor unit is configured to emit a third ultrasonic wave, wherein the second sensor unit is configured to ascertain a second orientation between the second sensor unit and the reference of the vehicle by adjusting the third ultrasonic wave, wherein the vehicle is configured to adjust the first orientation and / or the second orientation on the basis of a comparison between the first orientation and the second orientation.An advantage of this embodiment is that a possible incorrect determination of the orientation can be detected by means of the comparison of the first orientation and the second orientation and the determination of the orientation of the first sensor unit and / or of the second sensor unit can be repeated. Preferably, the second sensor unit, like the first sensor unit, is arranged in the rear region or in the front region.Further preferably, the vehicle has an axis of symmetry, wherein the first sensor unit and the second sensor unit are arranged substantially symmetrically to the axis of symmetry.An advantage of this embodiment is that the substantially similar and / or the same conditions exist for the first sensor unit and the second sensor unit if they are arranged symmetrically to one another in order to be able to further increase the comparison of the recorded ultrasonic values. For example, the axis of symmetry can be a longitudinal axis of a vehicle, so that the first sensor unit is arranged on a left side and the second sensor unit is arranged on the right side of the vehicle. The comparative ability of the received ultrasonic values and of the determined orientations can thus preferably be compared with one another. In this context, substantially symmetrical means in particular a deviation of + / -5%, in particular manufacturing-related tolerances.The first sensor unit is preferably configured to emit a first ultrasonic wave set, wherein the second sensor unit is configured to receive at least a part of the first ultrasonic wave set in order to determine the second orientation.An advantage of this embodiment is that a sensor unit on the vehicle can emit an ultrasonic wave set and a plurality of further or adjacent sensors can receive the reflection. In this way, assuming a vehicle with a flat floor, the position of the sensor units relative to one another can be checked. In this case, in particular statistical methods can be used.Brief Description of the DrawingsHereinafter, embodiments of the invention will be described in detail with reference to the accompanying drawings. In the drawing, the following is: FIG. 1 shows a sensor unit according to an embodiment, FIG. 2 shows a vehicle according to an embodiment, FIG. 3 illustrates a vehicle according to an embodiment.Embodiments of the InventionAll the same elements, units and / or systems are preferably provided with the same reference numerals in all the figures.FIG. 1 shows a sensor unit 10 according to an embodiment. Preferably, the sensor unit 10 has a printed circuit board unit 14 and at least two sensor elements 16 for determining an orientation 12 of the sensor unit 10, wherein the two sensor elements 16 are arranged on the printed circuit board unit 14, wherein the at least two sensor elements 16 are configured to emit and / or receive at least one first ultrasonic wave, wherein the sensor unit 10 is configured to determine the orientation 12 of the sensor unit 10 with respect to a reference 18 of a vehicle by adjusting the first emitted ultrasonic wave by means of the at least two sensor elements 16.As illustrated in FIG. 1, the sensor unit 10, which can be in particular a MEMS-based ultrasonic sensor array, comprises at least one printed circuit board unit 14. Ultrasonic sensors. As shown in FIG. 1, four sensor elements 16 are arranged in a 2 x 2 array on the circuit board unit. Thus, the sensor unit 10 can emit and / or receive at least one first ultrasonic wave by means of the two sensor elements or four sensor elements, preferably emit and / or receive a second ultrasonic wave, and / or further preferably emit and / or receive a plurality of ultrasonic waves. Further preferably, the sensor unit 10 can be configured to adjust a phase offset between the first ultrasonic wave and the second ultrasonic wave in order to determine the orientation 12 of the sensor unit 10. In this case, the wavefront can preferably be aligned upwards / downwards and left / right by adjusting the phase offset by means of the excitation by the sensor elements 16.FIG. 2 shows a vehicle 100 according to an embodiment. The vehicle 100 preferably has at least one first sensor unit 10. The first sensor unit 10 is preferably configured to emit at least one first ultrasonic wave, wherein the first sensor unit 10 is configured to determine a first orientation 12 of the first sensor unit 10 with respect to a reference 18 of the vehicle 100 by adjusting the first emitted ultrasonic wave. As is illustrated in FIG. 2, the first sensor unit 10 is located in a front region of the vehicle 100, in particular on a first side with respect to the axis of symmetry 54. As is illustrated in FIG. 2, the axis of symmetry 54 can preferably be a longitudinal axis of symmetry of the vehicle 100. Further preferably, the vehicle 100 has a reference 18, which can in particular be a coordinate system or the like according to DIN 70000. The vehicle 100 further preferably has a second sensor unit 50. The second sensor unit 50 can be configured to ascertain a second orientation 52. As illustrated in FIG. 2, the second sensor unit 50 is located on a second side to the axis of symmetry 54. Thus, a second sensor unit 50 can receive at least a part of the ultrasonic wave set or a plurality of further ultrasonic sensors, in order to be able to determine the second orientation 52.FIG. 3 shows a vehicle 100 according to an embodiment. The vehicle 100 has a sensor unit 10 for determining a first orientation 12 and a second sensor unit 50 for determining a second orientation 52 in relation to a reference 18 of the vehicle 100. As shown in FIG. 3, the vehicle 100 is located on a parking surface 101. The first sensor unit 10 and the second sensor unit 50 can emit at least one ultrasonic wave onto the placement surface 101 and determine it on the basis of the reflection or the changes of the ultrasonic wave by beamforming an orientation 12 or 52 in relation to the reference 18 of the vehicle 100.

Claims

Sensor unit (10) for determining an orientation (12) of the sensor unit (10) comprising: - a printed circuit board unit (14), - at least two sensor elements (16), - wherein the at least two sensor elements (16) are arranged on the printed circuit board unit (14), wherein the at least two sensor elements (16) are configured to emit and / or receive at least one first ultrasonic wave, wherein the sensor unit (10) is configured to determine the orientation (12) of the sensor unit (10) with respect to a reference (18) of a vehicle (100) by adjusting the first emitted ultrasonic wave by means of the at least two sensor elements (16).Sensor unit (10) according to claim 1, wherein the at least two sensor elements (16) are configured to emit at least one second ultrasonic wave, wherein the sensor unit (10) is configured to adjust a phase offset between the first ultrasonic wave and the second ultrasonic wave in order to determine the orientation (12) of the sensor unit (10).Sensor unit (10) according to claim 2, wherein the sensor unit (10) is configured to adjust the phase offset such that a first maximum of the first ultrasonic wave and / or a second maximum of the second ultrasonic wave move along a first axis and / or a second axis.Sensor unit (10) according to one of the preceding claims, wherein the sensor unit (10) is configured to emit the first ultrasonic wave on the basis of a predetermined orientation, wherein the sensor unit (10) is configured to compare a propagation time of the ultrasonic wave at the predetermined orientation with a predetermined reference value in order to determine the orientation (12) of the sensor unit (10).Sensor unit (10) according to one of the preceding claims, wherein the sensor unit (10) is configured to receive an initiation signal, wherein the sensor unit (10) is configured to determine the orientation (12) of the sensor unit (10) if the initiation signal is present.Sensor unit (10) according to one of the preceding claims, wherein the sensor unit (10) is configured to receive a temperature value and / or a geographical position, wherein the sensor unit (10) is configured to adapt the orientation (12) of the sensor unit (10) on the basis of the temperature value and / or the geographical position.Vehicle (100), comprising a first sensor unit (10) according to one of the preceding claims, wherein the first sensor unit (10) is configured to emit at least one first ultrasonic wave, wherein the sensor unit (10) is configured to determine a first orientation (12) of the first sensor unit (10) with respect to a reference (18) of the vehicle (100) by adjusting the first emitted ultrasonic wave.Vehicle (100) according to claim 7, wherein the vehicle (100) has a second sensor unit (50) according to one of claims 1 to 6, wherein the second sensor unit (50) is configured to emit a third ultrasonic wave, wherein the sensor unit (50) is configured to determine a second orientation (52) between the second sensor unit (50) and the reference (18) of the vehicle (100) by the adaptation of the third ultrasonic wave, wherein the vehicle (100) is configured to adapt the first orientation (12) and / or the second orientation (52) on the basis of a comparison between the first orientation (12) and the second orientation (52).Vehicle (100) according to claim 8, wherein the vehicle (100) has an axis of symmetry (54), wherein the first sensor unit (10) and the second sensor unit (50) are arranged substantially symmetrically to the axis of symmetry (54).The vehicle (100) according to any one of claims 8 to 9, wherein the first sensor unit (10) is configured to emit a first set of ultrasonic waves, wherein the second sensor unit (50) is configured to receive at least a part of the first set of ultrasonic waves to determine the second orientation (52).

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