Sensor installation with ultrasonic transceiver and optical transceiver device

Abstract

The present invention relates to a sensor installation (20, 21) for a vehicle (10) comprising an ultrasonic transceiver (100) designed to emit ultrasonic waves and receive reflected ultrasonic waves, and an optical transceiver device (101) designed to emit light and receive reflected light.

Description

[Technical Field]

[0001] The present invention relates to a sensor installation with an ultrasonic transceiver and an optical transceiver device, a method for measuring the surrounding environment of a motor vehicle, and a computer program product. [Background technology]

[0002] Vehicles, particularly automobiles, are equipped with ultrasonic transceivers that transmit ultrasonic transmit signals into the vehicle's environment and receive ultrasonic receive signals from the vehicle's environment. The distance to an object in the vehicle's environment is determined by the signal propagation time between the transmission of the ultrasonic transmit signal and the arrival of an ultrasonic echo in the ultrasonic receive signal due to the ultrasonic transmit signal being reflected by an object in the vehicle's environment. When multiple ultrasonic transceivers are used, the actual location of the reflection point can be determined by trilateration or the like.

[0003] Particularly for autonomous driving, such as automatic parking and starting, reliable detection of small or thin obstacles, such as pillars or horizontal bars, is essential. Reliable detection of obstacles even when they are very close to the ultrasonic transceiver is essential. Many conventional ultrasonic transceivers are generally unable to detect obstacles within close range, e.g., less than 20 cm from the transceiver. In such ultrasonic transceivers, a membrane is used to generate an ultrasonic transmission signal and to receive a received ultrasonic signal reflected by an obstacle. To generate the ultrasonic transmission signal, the membrane is typically excited by a piezoelectric element, causing it to vibrate. After the excitation is stopped, the membrane continues to vibrate. While the membrane is vibrating or continues to vibrate, the ultrasonic transceiver cannot detect or barely detects the reflected received ultrasonic signal. The closer the obstacle is to the ultrasonic transceiver, the shorter the time of flight between the transmission of the ultrasonic transmission signal and the reception of the reflected received ultrasonic signal. If the reflection reaches the ultrasonic transceiver while the membrane is vibrating or continues to vibrate, the obstacle will not be detected.

[0004] An ultrasonic sensor is known from EP 3012654 A1, which has a damping element arranged in the housing for damping the vibrations of the membrane, which reduces the vibrations of the membrane and thereby allows for better detection of obstacles at close range.

[0005] A back-up warning system with an ultrasonic sensor is known from DE 102013226499 A1. The back-up warning system includes an ultrasonic sensor configured to detect information about the area behind the vehicle and a capacitive sensor configured to detect information about the area behind the vehicle within a predetermined distance. Even if the ultrasonic sensor does not detect obstacles located behind the vehicle, the capacitive sensor can be configured to detect obstacles located behind the vehicle.

[0006] A sensor arrangement for detecting labels on carrier materials is known from DE 102007046769 A1. The sensor arrangement comprises an optical sensor and an ultrasonic sensor for detecting the labels. Both the optical sensor and the ultrasonic sensor operate according to transmission measurements. That is, the transmitter and receiver of the optical sensor and the ultrasonic emitter and receiver of the ultrasonic sensor are arranged on either side of a detection plane through which the carrier material carrying the label is guided relative to the device. Summary of the Invention

[0007] Against this background, one object of the present invention is to further improve a sensor installation with an ultrasonic transceiver and the measurement of the surrounding environment of a motor vehicle at short distances by means of ultrasonic waves.

[0008] Therefore, a sensor installation for a vehicle is proposed, comprising an ultrasonic transceiver configured to emit ultrasonic waves and receive reflected ultrasonic waves, and an optical transceiver device configured to emit light and receive reflected light.

[0009] The combination of an ultrasonic transceiver and an optical transceiver device allows the optical transceiver device to detect close distances that are not detected or not well detected by the ultrasonic transceiver. The close distance of the ultrasonic transceiver includes, for example, up to 5 cm, 10 cm, or 15 cm from the ultrasonic transceiver, depending on the ultrasonic transceiver and its operation. The optical transceiver device can detect at distances of, for example, up to 20 cm, 15 cm, 10 cm, or 5 cm, depending on the optical transceiver device and its operation.

[0010] In this example, the optical transceiver device may operate as a type of optical switch. The optical transceiver device emits light, which may be reflected from nearby surfaces. A portion of the reflected light is received by the optical transceiver device. If a set value is exceeded, an obstacle is detected. The area covered by the optical transceiver device can be set by selecting a threshold value and by assumptions about reflection, such as the reflectivity of the surface, the shape of the object, or the scattering of light by obstacles that typically occur with the light used. In this type of operation, the optical transceiver device or its evaluation device only provides information about the presence or absence of an obstacle. This information can be further processed and linked, for example, to data from other sensors stored in the vehicle or to a map of the vehicle's surroundings.

[0011] The proposed sensor installation can be used to reduce risks during autonomous driving, since an incorrectly detected obstacle poses less risk than an incorrectly not detected obstacle, especially for automatic starting.

[0012] The sensor equipment, including the ultrasonic transceiver and the optical transceiver device, can be preassembled into an assembly. The sensor equipment may include a housing, a microprocessor such as an ASIC, memory, and / or electrical connections. The sensor equipment is specifically designed to be installed in a trim part of a vehicle, such as a bumper, front apron, or rear apron, with at least a portion of the sensor equipment exposed. The sensor equipment may be disposed in a corresponding recess or passage opening in the trim part. Such sensor equipment is partially visible when installed in the vehicle as intended. In the installed state, the ultrasonic transceiver can emit ultrasonic waves and receive reflected ultrasonic waves through the visible area, and the optical transceiver device can emit light through the visible area and receive reflected light. In this case, neither the ultrasonic waves nor the light are interfered with during propagation. The ultrasonic transceiver and the optical transceiver device may be disposed in at least a portion of a common housing.

[0013] According to one embodiment, the ultrasonic transceiver and the optical transceiver device are in particular connected to one another so as to form a pre-assembled unit and / or so as not to be disassembled without destruction, in particular the ultrasonic transceiver and the optical transceiver device are arranged in a (preferably common) housing.

[0014] The sensor installation is useful for installation in a vehicle, for example, as the ultrasonic transceiver and optical transceiver devices are connected together to form a stable assembly for installation.

[0015] During operation, a vehicle, such as an automobile, is subject to environmental influences, such as vibrations, heat, cold, rain, humidity, sunlight, and wind. For this purpose, the ultrasonic transceiver and optical transceiver devices in the sensor installation may be arranged or partially arranged in a (particularly common) protective housing and may be connected to each other and / or to the housing, for example by embedding, embedding, gluing, or welding, so that they cannot be disassembled without destruction. In this way, the sensor installation can also be protected from environmental influences.

[0016] According to one embodiment, the optical transceiver device comprises a light emitting diode or a laser, in particular for infrared, visible or ultraviolet light.

[0017] A variety of inexpensive optical transmitters are available for use in optical transceiver devices. In this example, semiconductor-based light-emitting diodes and lasers are particularly useful. Light-emitting diodes are less focused and typically have lower output than lasers, but are easier to handle. Usable wavelength ranges are those outside the visible wavelength range and / or those lacking significant interfering ambient light. Particularly in the near-infrared region, specifically the wavelength range between 780 nm and 1000 nm, optical transmitters can be inexpensively realized using semiconductor components, particularly photodiodes and phototransistors.

[0018] According to one embodiment, the optical transceiver device comprises a photodiode or a phototransistor.

[0019] Photodiodes or phototransistors are used as optical receivers that can receive light emitted by an optical transmitter and reflected from an object. Phototransistors are more sensitive than photodiodes because they also function as amplifiers. Photodiodes are often faster than phototransistors. Photodiodes and phototransistors are inexpensive components based on semiconductors that receive light in the wavelength range of 780 nm to 1000 nm. When using a phototransistor, light reflected from nearby surfaces can reach the phototransistor, and the threshold for obstacle detection can be set directly using a comparator circuit.

[0020] According to one embodiment, the optical transceiver device comprises two infrared light emitting diodes and two phototransistors or photodiodes.

[0021] The optical transceiver device can be designed for redundancy using two or more infrared light-emitting diodes and two or more phototransistors or photodiodes. This ensures that failure of an individual optical transmitter or optical receiver does not result in failure or degradation of the sensor equipment. The optical transceiver device can operate even if the optical transmitter or optical receiver is not completely covered by dirt. Functions such as dirt detection can also be achieved using multiple optical transmitters and optical receivers.

[0022] According to one embodiment, the sensor installation comprises an isolation ring for isolating the vibrations of the ultrasonic transceiver of the sensor installation from the containing device.

[0023] Ultrasonic transceivers typically convert electrical vibrations into mechanical vibrations using a piezoelectric element that excites a membrane. The vibration of the membrane generates an ultrasonic transmission signal. To convert as much power as possible into the ultrasonic transmission signal, the mechanical vibrations should not be transmitted to the component in which the ultrasonic transceiver is located. To minimize this transmission, the ultrasonic transceiver or an assembly incorporating the ultrasonic transceiver can be placed on or connected to the component via an isolation ring. Thus, for example, the ultrasonic transceiver can be installed in a housing along with its electronics, and the housing and / or ultrasonic transceiver can be placed on a bumper using an isolation ring.

[0024] According to one embodiment, the isolation ring is configured to conduct the transmitted light and / or the reflected light to an optical transceiver device.

[0025] In many applications, the ultrasonic transceiver should be integrated into the vehicle in an unobtrusive, aesthetically pleasing, and aerodynamically compatible manner, for example in the bumper, front apron, or rear apron, and an isolation ring is used for isolation from the vehicle or the bumper, front apron, or rear apron. If this isolation ring can be used for the transmitted and / or reflected light of the optical transceiver device, the proposed sensor arrangement can be used with no or little modification to the exterior area of ​​the vehicle.

[0026] According to one embodiment, the separating ring is transparent to the emitted and / or reflected light, in particular to infrared light.

[0027] One possibility for constructing the separating ring for conducting the transmitted or reflected light to the optical transceiver device is represented by a material for the coupling ring that is transparent to the emitted or reflected light, in particular to infrared light. If the optical transceiver device uses infrared light, it is also possible to use, for example, a material that is transparent to infrared light but not to visible light.

[0028] According to one embodiment, the isolation ring comprises optical fibers for conducting the emitted and / or reflected light.

[0029] Optical fibers may be used, for example, for beamforming of the emitted or reflected light, for better light separation or concentration, and / or for conducting the light to a separation ring.

[0030] According to one embodiment, the bumper, the front apron or the rear apron is equipped with one or more sensor installations.

[0031] According to one embodiment, the vehicle is equipped with one or more sensor arrangements and / or a bumper, a front apron or a rear apron with one or more sensor arrangements.

[0032] For use in driver assistance systems such as parking systems, the sensor arrangement can be mounted on the vehicle at a point in front or behind the vehicle in the direction of travel so that the sensor arrangement can detect obstacles in this area. Thus, one or more sensor arrangements can be arranged on the vehicle, in particular on the bumper, front apron or rear apron of the motor vehicle.

[0033] Furthermore, a method is proposed for measuring the surrounding environment of a vehicle, in particular using the above-mentioned sensor equipment, comprising the steps of a) transmitting and receiving ultrasonic signals, b) transmitting and receiving optical signals, c) evaluating the received ultrasonic signals with respect to obstacles in the surrounding environment of the vehicle, and d) evaluating the received optical signals with respect to obstacles in the surrounding environment of the vehicle.

[0034] The surrounding environment is measured using the transmission and reception of ultrasonic signals and the evaluation of the received ultrasonic signals for obstacles in the vehicle's surrounding environment. The distance to the obstacle is determined by time-of-flight measurements, and if there are multiple ultrasonic transceivers transmitting ultrasonic signals, the location of the obstacle can be determined by trilateration. Since ultrasonic transceivers usually cannot detect obstacles at close ranges below a minimum distance, the close range is supplemented using optical measurements. For this purpose, optical signals are transmitted and received. The received optical signals are evaluated for possible reflections from obstacles located close to the ultrasonic transceivers.

[0035] According to one embodiment, the received ultrasonic signals are evaluated for obstacles at a distance of more than 5 cm, preferably more than 10 cm, from the transmitting ultrasonic transceiver device, and / or the received optical signals are evaluated for obstacles at a distance of up to 20 cm, preferably up to 15 cm, from the transmitting optical transceiver device.

[0036] Ultrasonic transceivers typically cannot detect obstacles at close range. Close range refers to a distance at which an obstacle cannot be detected, and can include 5 cm, 10 cm, or 15 cm, depending on the design. Obstacles within this close range are detected by the received optical signal. For this purpose, the received optical signal is evaluated for obstacles at close ranges of up to 20 cm, 15 cm, 10 cm, or 5 cm. The location and orientation of the obstacle can be determined by trilateration using multiple ultrasonic transceivers. In evaluating the optical signal, it is often sufficient to establish the presence of an obstacle. This enables a cost-effective system for transmitting and receiving optical signals and evaluating the transmitted and received optical signals. When the evaluation of the optical signal is limited to close ranges, especially those not detected by the ultrasonic transceiver, the evaluation of the optical signal can be simply supplemented with information about the presence or absence of obstacles, especially those not detected by the ultrasonic transceiver.

[0037] In one embodiment, deactivation is permitted, particularly for an automatic activation process, only if the evaluated ultrasonic signal and the evaluated optical signal indicate that there are no obstacles in the intended direction of movement, particularly within the intended distance of movement.

[0038] Particularly in automated driving, minimizing risks or reducing redundancy in various sensor systems is important. Particularly in the case of a stationary vehicle, the vehicle's surroundings can suddenly change, for example, due to a pedestrian in the vicinity, for example, when the pedestrian steps into the rear of the stationary vehicle. When the ultrasonic transceiver is switched off, for example, because the vehicle is switched off, the vehicle's surroundings can change in a way that cannot be detected using the ultrasonic transceiver. If an obstacle (which can no longer be detected by the ultrasonic transceiver) is already located in the vicinity of the ultrasonic transceiver when the vehicle is switched on, the obstacle will no longer be detected by the ultrasonic transceiver. The risk of undetected obstacles in the vicinity can be reduced if deactivation is permitted only if both the evaluation of the ultrasonic signal and the optical signal indicate that no obstacle is present.

[0039] In one embodiment, the soiling of the sensor installation is established using at least two infrared diodes and using at least two phototransistors or photodiodes in the sensor installation.

[0040] In a system with multiple optical transmitters and receivers, e.g., two infrared diodes and two phototransistors, if the first phototransistor receives no reflected signal but the second phototransistor receives a reflected signal above a threshold, it can be concluded that the optical path to the first phototransistor is blocked, e.g., by mud. This is particularly true when the two optical receivers are positioned adjacent to each other, e.g., less than 30 mm apart. If the optical transmitters, e.g., the first and second infrared diodes, alternately transmit and the reflected signals reaching the optical receivers differ in intensity by more than a threshold, it can be concluded that the optical path from the infrared diode generating the weaker reflected signal to the reflecting object is blocked, e.g., by mud. This is particularly true when the two optical transmitters are positioned adjacent to each other, e.g., less than 30 mm apart.

[0041] It is further proposed a computer program product comprising instructions which, when executed by a computer, cause the computer to carry out the method described above.

[0042] The computer program product, e.g. computer program means, may be provided or supplied on a storage medium, e.g. a memory card, USB stick, CD-ROM, DVD, etc., or in the form of a file that can be downloaded from a server in a network. This may be done, for example, by transmitting the computer program product or a corresponding file containing the computer program means in a wireless communication network.

[0043] The embodiments and features described for the proposed apparatus apply equally to the proposed method, and vice versa, and the embodiments and features described for the proposed method apply equally to the proposed apparatus.

[0044] Also included are combinations of features or embodiments not explicitly mentioned above or below with respect to the exemplary embodiments of the invention, in which case the skilled person will add individual aspects as improvements or additions to the respective basic form of the invention.

[0045] Further advantageous configurations and aspects of the invention are the subject of the dependent claims and the following exemplary embodiments of the invention.The invention will be explained in more detail below on the basis of preferred embodiments and with reference to the accompanying drawings. [Brief explanation of the drawings]

[0046] [Figure 1] FIG. 1 shows a schematic top view of a vehicle with a sensor installation and an obstacle. [Figure 2] Figure 2 shows the reflection of ultrasound waves from the sensor installation and an obstacle. [Figure 3] Figure 3 shows the sensor installation, the reflection of ultrasound off nearby obstacles, and the blocking of more distant objects. [Figure 4] Figure 4 shows the sensor installation, the reflection of ultrasound waves on nearby obstacles, the occlusion of more distant objects, and the illumination of the obstacles using light. [Figure 5] FIG. 5 shows a schematic cross section of a sensor installation with an ultrasonic transceiver and an optical transceiver device in the front apron. [Figure 6] FIG. 6 shows a schematic top view of a sensor installation with ultrasonic transceiver and optical transceiver devices in the front apron. [Figure 7] FIG. 7 shows a flow chart of a method for measuring the surrounding environment of a vehicle. DETAILED DESCRIPTION OF THE INVENTION

[0047] In the drawings, identical or functionally identical elements are designated by the same reference numbers unless otherwise noted.

[0048] 1 shows an exemplary vehicle, i.e., automobile 10, having a number of sensor installations 20, 21 with ultrasonic transceivers. The sensor installations 20, 21 are arranged in a front apron 60 and a rear apron of the automobile 10 (neither of which is directly visible in the top view of FIG. 1). In the schematic illustration, the sensor installations 20, 21 are shown superimposed to allow a better recognition. In many automobiles 10, the sensor installations 20, 21 are realized as flat surfaces and therefore do not protrude, or only protrude minimally, from the front or rear apron or are arranged recessed relative to them.

[0049] The ultrasonic transceiver of the sensor installation 20, 21 is realized with a cup-shaped membrane that ends flush with the exterior of the vehicle and can be painted in the color of the automobile 10. The flat surface of the membrane is attached to the flat surface of the front apron 60 or rear apron. The sensor installation 20, 21 is often only recognizable by a silicone separator, which appears as a circle, between the front or rear apron and the sensor installation 20, 21.

[0050] The spread 30 of the transmitted ultrasonic waves is shown for the ultrasonic transceiver of the sensor installation 21. The ultrasonic transceiver of the sensor installation 21 transmits ultrasonic waves into the surrounding environment 40 of the motor vehicle 10. The ultrasonic transceiver of the sensor installation 21 transmits maximum power perpendicular to the surface of the membrane attached to the plane of the front apron. In the horizontal plane, the transmitted ultrasonic waves have a directivity opening angle of approximately 120°. In the vertical plane, the opening angle is approximately 60°.

[0051] The transmitted ultrasonic waves may be reflected by an obstacle 50. The distance of the obstacle 50 from the ultrasonic transceiver of the installation 21 can be calculated from the combination of the flight time of the transmitted ultrasonic waves to the obstacle and the flight time of the reflected ultrasonic waves back to the ultrasonic transceiver of the sensor installation 21. If multiple ultrasonic transceivers of the sensor installations 20, 21 are used, the position of the obstacle 50 can be determined from the various flight times by known trilateration methods.

[0052] FIG. 2 shows a schematic representation of the sensor installation 20 and the reflection of ultrasound waves at an obstacle 50. The ultrasound waves are transmitted as a pulse or a sequence of pulses. The ultrasound waves are directional and propagate with an opening angle of approximately 120° in the horizontal plane of the vehicle 10. The propagation path 30 of the transmitted ultrasound waves is shown by a solid arc in FIG. 2. When the transmitted ultrasound waves strike the obstacle 50, a portion of the transmitted ultrasound waves striking the obstacle 50 may be reflected. The propagation path 70 of the reflected ultrasound waves is shown by a dotted arc in FIG. 2. A portion of the reflected ultrasound waves strikes the ultrasonic transceiver of the sensor installation 21. The distance of the obstacle from the ultrasonic transceiver of the sensor installation 21 can be calculated from the time of flight of the pulse or pulse sequence from the ultrasonic transceiver of the sensor installation to the obstacle 50 and back.

[0053] FIG. 3 illustrates the reflection of ultrasonic waves from the sensor equipment 21, nearby obstacles, and the blocking of more distant objects. As the obstacle 50 in FIG. 2 approaches the ultrasonic transceiver of the sensor equipment 21, the time of flight of the round-trip pulse or pulse sequence from the ultrasonic transceiver to the obstacle becomes shorter. If the reflected ultrasonic waves reach the ultrasonic transceiver while these ultrasonic waves are still being transmitted as a pulse or pulse sequence, or immediately after transmission, the ultrasonic transceiver becomes "blind" to the reflected ultrasonic waves. In this case, it can no longer detect the obstacle 50. If the obstacle 50 is laterally offset, as shown by the dotted line in FIG. 3, it can be detected even at the same distance from the front apron 60 due to its longer time of flight. For many ultrasonic transceivers, a distance of at least 10 cm from the ultrasonic transceiver is required to detect the obstacle 50. This is because in this case the time of flight of the ultrasound waves transmitted in the form of a pulse or pulse sequence is long enough that the membrane is no longer excited and stops vibrating, allowing the reflected ultrasound waves to be received and the reflection by the obstacle 50 to be detected.

[0054] In the case of an obstacle 50 located in the vicinity in front of the ultrasonic sensors of the sensor installation 21, there is an additional risk that a very large obstacle 80 behind the obstacle 50 may be blocked. The obstacle 50 reflects or scatters the incident ultrasonic waves, so that these do not reach the object 80 or can reach it only in an attenuated form.

[0055] FIG. 4 illustrates the sensor installation 21, the reflection of ultrasound waves from nearby obstacles (the corresponding ultrasonic transceiver of the sensor installation 21 is not shown in FIG. 4), the obstruction of more distant objects, and the illumination of the obstacles with light. When light is emitted and the reflected light is received by the sensor installation 21 with an optical transceiver device (not shown in FIG. 4), this can be used as additional information about whether an obstacle is located in front of the sensor installation 21. In the exemplary embodiment of FIG. 4, the propagation of light is illustrated based on two cones of light. Two infrared diodes emit light at a wavelength of 850 nm. When the emitted light hits an obstacle 50, a portion of the light is reflected. The reflected light can be received by two phototransistors. A comparator circuit is used to define a threshold for the phototransistors. If the threshold is exceeded, the obstacle can be detected. In this way, additional safety is provided by ensuring that obstacles in the close range of the ultrasonic transceiver of the sensor installation 21 are not overlooked. An optical transceiver device using infrared diodes and phototransistors can be implemented cost-effectively. Incorporating an ultrasonic transceiver device into a conventional ultrasonic sensor, rather than an optical transceiver device, is often easily achievable because existing electronics 140, such as ICs, ASICs, microprocessors, and memory, can also be used. Often, the ultrasonic sensor IC is provided with so-called GPIOs (general purpose input / output) that can be used for signal processing of the ultrasonic transceiver device, such as connecting to a phototransistor and measuring the voltage across the phototransistor generated by the received reflected light.

[0056] FIG. 5 shows a schematic cross-section of a sensor installation 21 including an ultrasonic transceiver 100 and an optical transceiver device 101 mounted in a front apron 60. The ultrasonic transceiver 100 and the optical transceiver device 101 are preferably integrated into a common housing 105. A membrane 110 of the ultrasonic transceiver 100 is disposed in the housing 105 or partially disposed within the housing 105. The membrane 110 is cup-shaped and has a flat area that fits into the plane of the front apron 60 and a cylindrical area with a greater material thickness. The membrane 110 is connected to the housing 105 via the cylindrical area. The connection is established by a potting compound 120. Alternatively, the membrane 110 can be connected to the housing 105 by, for example, bonding, extrusion, or embedding. The membrane 110 is connected to the housing 105 by the potting compound 120, preventing water from penetrating into the housing. The membrane is made of metal, in particular aluminum. A piezoelectric element 130 is disposed within and protected by the membrane 110 .

[0057] The membrane 110 and the piezoelectric element 130 are part of the ultrasonic transceiver 100. The electronics 140 of the ultrasonic transceiver 100, which includes a microprocessor with memory, is used to generate pulses or pulse sequences having a carrier frequency using the piezoelectric element 130. The pulses or pulse sequences are transmitted using the membrane 110. The electronics 140 of the ultrasonic transceiver 100 is also used to evaluate ultrasonic waves that strike the membrane 110, particularly in the form of reflected pulses or pulse sequences.

[0058] Also embedded in the potting compound 120 are an infrared light emitting diode 150 and a phototransistor 160. The infrared light emitting diode 150 and the phototransistor 160 are part of the optical transceiver device 101. An electronics 170 of the optical transceiver device 101, which has a microprocessor with memory, is used to emit an optical signal using the infrared light emitting diode 150 and to receive and evaluate the optical signal using the phototransistor 160. The infrared light emitting diode 150 and the phototransistor 160 are also firmly connected to the housing 105 via the potting compound 120. In the housing 105, the light emitting diode 150 and the phototransistor 160 are connected to the electronics 170 of the optical transceiver device via wires or conductor tracks. Common electronics 140, 170 can be used for the ultrasound transceiver 100 and the optical transceiver device 101.

[0059] The housing 105 has a connection 180, for example a plug connection. The connection 108 is for supplying electrical energy to the optical transceiver device 101 and the ultrasonic transceiver 100 and for transmitting data to and from the optical transceiver device 101 and the ultrasonic transceiver 100, for example from a control unit of the automobile 10. The housing 105 is arranged on the front apron 60 using an isolation ring 190. The isolation ring 190 is extruded onto the membrane 110 and the embedding compound 120. Alternatively, the isolation ring 190 may be plugged, embedded, or bonded. The isolation ring 190 reduces the transmission of vibrations of the membrane 110 to the front apron 60, either directly or via the housing 105.

[0060] An optical fiber 200 is introduced, for example buried, in the isolation ring 190. Light from the infrared light-emitting diode 150 can reach the outside of the front apron 60 and can be emitted into the surrounding environment 40 of the vehicle 10 via the optical fiber. Vice versa, reflected light can reach the phototransistor 160 from the surrounding environment 40 of the vehicle 10.

[0061] FIG. 6 shows a schematic top view of a sensor installation 21, including an ultrasonic transceiver and an optical transceiver device, mounted on the front apron 60, as seen from the surroundings 40 of the vehicle 10. The isolation ring 190 is transparent to the light from the infrared-emitting diodes 150, so the sensor installation 21 does not require a waveguide 200. This is because the light emitted and received by the optical transceiver device passes through the isolation ring 190. The isolation ring 190 has a circumference of approximately 30 mm. The sensor installation 21 can be installed in an installation space that is also available for conventional ultrasonic sensors. This is because the isolation ring 190, which surrounds the membrane 110, is used to emit light for the optical transceiver device and receive the reflected light. Due to the compact configuration of the sensor installation 21, the optical transceiver device can provide good coverage over a short distance in front of the ultrasonic transceiver device.

[0062] In FIG. 6, the sensor equipment 21 for the optical transceiver device includes two infrared-emitting diodes 150 and two phototransistors 160. The detection range of the optical transceiver device is determined by the use of two infrared-emitting diodes 150 and two phototransistors 160, and the system can be implemented redundantly. For example, arranging the infrared-emitting diodes 150 in a horizontal plane provides wider detection in the horizontal plane. Arranging them in a vertical plane provides better detection of obstacles in the vertical direction at close range. Even if the infrared-emitting diodes 150 or phototransistors 160 do not reflect light due to dirt, this can be compensated for by the other pair of infrared-emitting diodes 150 and phototransistors 160.

[0063] In evaluating the received optical signal at a pair of infrared light emitting diodes 150 and phototransistors 160 located close to each other, for example the upper pair in Figure 6, if a strong reflection occurs due to the strong received optical signal, or if no reflection occurs at a second pair located close to each other, for example the lower pair in Figure 6, it can be concluded that there is dirt in the area of ​​the sensor equipment 21 that is blocking the upper pair of infrared light emitting diodes 150 and phototransistors 160 of the sensor equipment 21.

[0064] FIG. 7 shows a flow chart of a method for measuring the surrounding environment 40 of the vehicle 10 that can be implemented in particular using the sensor devices 20, 21 described above.

[0065] In step S1, ultrasonic signals are transmitted and received using an ultrasonic transceiver. The ultrasonic transceiver has a membrane 110 for this purpose. The membrane 110 can be excited using a piezoelectric element 130 and can generate ultrasonic waves. The piezoelectric element 130 and the membrane 110 can be excited using the ultrasonic transceiver's electronics 140. This transmits an ultrasonic signal. When the transmitted ultrasonic signal hits an obstacle 50, some of it may be reflected. When the reflected ultrasonic signals hit the membrane 110 again, they are received by the ultrasonic transceiver.

[0066] In step S2, optical signals are transmitted and received using the optical transceiver device. Step S2 can be performed in parallel with step S1, or alternately before or after step S1. The light-emitting diode 150 is turned on using the electronics 170 of the optical transceiver device, and an optical signal is emitted using the light-emitting diode. When the emitted optical signal hits an obstacle 50, some of the signal may be reflected. When the reflected optical signal hits the phototransistor 160 or photodiode of the optical transceiver device, it can be received by the optical transceiver device.

[0067] In step S3, the received ultrasonic signal is evaluated for obstacles 50 in the vehicle's 10 environment 40. For this purpose, a search is made for peaks in the received ultrasonic signal corresponding to reflections from the obstacle 50. The distance to the obstacle 50 is calculated from the time of flight of the ultrasonic signal to the obstacle 50 and back to the ultrasonic transceiver. If multiple ultrasonic transceivers are used, the location of the obstacle can also be determined by trilateration. However, if the obstacle 50 is too close to the ultrasonic transceiver, the reflected signal will not be received if it reaches the membrane 110 while the membrane is still excited for ultrasonic transmission or still vibrating from the excitation. In this case, the obstacle will not be detected.

[0068] In step S4, the received optical signal is evaluated for obstacles 50 in the vehicle's 10 environment. Step S4 can be performed in parallel with step S3 or alternately before and after. In this case, the brightness of the received optical signal is compared with a threshold. If the brightness value exceeds the threshold, an obstacle is detected. For the evaluation, an optical signal having a wavelength that is as unlikely to be naturally present in the vehicle's 10 environment 40 as possible, or not present at all, such as near-infrared light, is used. The threshold is selected so as to detect only obstacles 50 that are too close to the ultrasonic transceiver to be detected by the ultrasonic transceiver. For example, the threshold can be experimentally defined to detect frequent or particularly significant obstacles 50, such as pedestrians, as much as possible. Only if no obstacle is detected does the electronics 170 authorize the optical transceiver device to be deactivated. Only if the electronics of the optical transceiver device and the ultrasonic transceiver electronics 140 are deactivated is the automated driving operation authorized to be deactivated, e.g., to initiate an automated parking entrance or exit process.

[0069] 10. Automobiles 20, 21 Sensor equipment 30 Ultrasonic Wave Propagation 40 Vehicle Surrounding Environment 50 Obstacles 60 Front apron 70 Propagation of reflected ultrasound waves 80 Object 90 light cone 100 Ultrasonic Transceiver 101 Expensive transceiver equipment 105 Housing 110 membrane 120 Implantable composition 130 Piezoelectric element 140 Ultrasonic Transceiver Electronics 150 Infrared Light Emitting Diode 160 Phototransistor 170 Electronic equipment for optical transceiver devices 180 Connection 190 Separation Ring 200 Optical Fiber S1: Ultrasonic signal transmission and reception step S2: Optical signal transmission and reception step S3 Evaluation step of the received ultrasonic signal S4: Evaluation of received optical signals

Claims

1. an ultrasonic transceiver (100) configured to transmit ultrasonic waves and receive reflected ultrasonic waves; and an optical transceiver device (101) configured to emit light and receive reflected light.

2. The sensor installation (20, 21) according to claim 1, wherein the ultrasonic transceiver (100) and the optical transceiver device (101) are arranged in a housing (105).

3. 3. The sensor installation (20, 21) according to claim 1 or 2, wherein the optical transceiver device (101) comprises a light emitting diode (150) or a laser, in particular for infrared, visible or ultraviolet light.

4. The sensor installation (20, 21) according to any one of claims 1 to 3, wherein the optical transceiver device (101) comprises a photodiode or a phototransistor (160).

5. The sensor installation (20, 21) according to any one of claims 1 to 4, wherein the optical transceiver device (101) comprises two infrared emitting diodes (150) and two phototransistors (160) or photodiodes.

6. The sensor installation (20, 21) according to any one of claims 1 to 5, comprising an isolation ring (190) for isolating vibrations of the ultrasonic transceiver (100) of the sensor installation (20, 21) from a device (60) housing the sensor installation (20, 21).

7. The sensor installation (20, 21) of claim 6, wherein the isolation ring (190) is configured to conduct the transmitted light and / or the reflected light to the optical transceiver device (101).

8. 8. The sensor arrangement (20, 21) according to claim 6 or 7, wherein the separating ring (190) is transparent to the emitted and / or reflected light, in particular to infrared light.

9. 9. The sensor arrangement (20, 21) according to claim 7 or 8, wherein the separating ring (190) comprises optical fibers (200) for conducting the emitted and / or reflected light.

10. A bumper, a front apron (60) or a rear apron, comprising one or more sensor arrangements (20, 21) according to claims 1 to 9.

11. A vehicle (10) comprising one or more sensor installations (20, 21) according to any one of the preceding claims and / or a bumper, a front apron (60) or a rear apron.

12. A method for measuring the surrounding environment (40) of a vehicle (10), in particular using a sensor installation (20, 21) according to any one of claims 1 to 9, comprising: a) transmitting and receiving ultrasonic signals; b) transmitting and receiving optical signals; c) evaluating the received ultrasonic signals with respect to obstacles in the surrounding environment (40) of the vehicle (10); d) evaluating the received optical signal with respect to obstacles in the surrounding environment (40) of the vehicle (10).

13. 13. The method of claim 12, wherein the received ultrasonic signals are evaluated for obstacles (50) at a distance of at least 5 cm, preferably at least 10 cm, from the transmitting ultrasonic transceiver (100) and / or the received optical signals are evaluated for obstacles at a distance of less than 20 cm, preferably less than 15 cm, from the transmitting optical transceiver device (101).

14. 14. The method according to claim 12 or 13, wherein deactivation, in particular for an automatic activation process, is permitted only if the evaluated ultrasonic signal and the evaluated light signal indicate that there are no obstacles in the intended direction of movement, in particular within the intended distance of movement.

15. A computer program product comprising instructions which, when executed by a computer, cause the computer to carry out the method according to any of claims 12 to 14.

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