Motor vehicle with an opening hood and method for operating a collision protection system for a hood

Abstract

Motor vehicle (1) comprising an openable, manually operated bonnet (2) which sweeps over a movement area (7) during an opening and a closing operation, and a collision protection system for the bonnet (2), wherein the collision protection system comprises: - at least one radar sensor (9, 10) assigned to the hood (2) in a direction of movement, including opening and closing, which is arranged to detect at least part of the movement area, at least when the hood (2) is not in the end position (5, 6) of the direction of movement, and - a control device (12) designed to evaluate the radar data of the radar sensor (9, 10) for obstacles (8) located in the movement area (7), wherein, if an obstacle (8) is present in the movement area (7) and if a measure criterion indicating an imminent movement of the hood (2) is fulfilled, the control device (12) as a measure activates an output device to issue a warning message, wherein the measure criterion indicating an imminent movement of the hood (2) checks, in order to anticipate a manual movement process, whether the hood (2) has been unlocked and / or is open.

Description

[0001] The invention relates to a motor vehicle having an openable, manually operated hood that covers a range of motion during an opening and closing process. The invention also relates to a method for operating a collision protection system for a hood of such a motor vehicle.

[0002] The use of radar sensors in motor vehicles is already widely known in the state of the art. Radar sensors are now typically used as environment sensors for medium and long distances, enabling them to determine the distance, angle, and relative speed of other road users or larger objects. Such radar data can be incorporated into environment models or made available directly to vehicle systems. In the known state of the art, radar data is used, for example, by longitudinal guidance systems such as ACC or safety systems. The use of radar sensors in the interior of the vehicle has also been proposed.

[0003] Conventional radar sensors are typically larger and rather bulky, as the antennas and the electronic components required directly at the antenna, i.e., the radar front end, are integrated into a single housing. The electronic components primarily comprise the radar transceiver, which contains a frequency controller (usually comprising a phase-locked loop (PLL), mixing devices, a low-noise amplifier (LNA), and the like. However, control modules and digital signal processing components are often also implemented close to the antenna, for example, to transmit pre-processed sensor data, such as object lists, to a connected bus, such as a CAN bus.

[0004] For a long time, the realization of semiconductor-based radar components proved difficult due to the need for expensive specialty semiconductors, particularly GaAs. Smaller radar sensors were proposed, with the entire radar front end implemented on a single chip using SiGe technology, before solutions using CMOS technology became known. Such solutions are the result of the extension of CMOS technology to high-frequency applications, often referred to as RF-CMOS. Such a CMOS radar chip is extremely small in size and does not use expensive specialty semiconductors, thus offering significant advantages over other semiconductor technologies, especially in terms of manufacturing. An example of a 77 GHz radar transceiver implemented as a CMOS chip is described in the article by Jri Lee et al., "A Fully Integrated 77-GHz FMCW Radar Transceiver in 65-nm CMOS Technology," IEEE Journal of Solid State Circuits 45 (2010), pp. 2746-2755.

[0005] Since it was also proposed to implement the chip and antenna in a single package, an extremely cost-effective, small radar sensor is possible. This sensor can significantly better meet installation space requirements. Due to the short signal paths, it also has a very low signal-to-noise ratio and is suitable for high frequencies and larger, variable frequency bandwidths. Therefore, such small-scale radar sensors can also be used for short-range applications, for example, in the range of 30 cm to 10 m.

[0006] It has also been proposed to provide such a CMOS transceiver chip and / or a package containing the CMOS transceiver chip and antenna on a common circuit board with a digital signal processing processor (DSP processor), or to integrate the signal processing processor functions into the CMOS transceiver chip. A similar integration is possible for control functions.

[0007] The use of radar sensors has also been proposed for collision avoidance when opening vehicle side doors. For example, a driver assistance system is known that implements an exit warning function. A radar sensor located at the rear of the vehicle monitors the rear area of ​​the vehicle and provides radar data that is evaluated for the approach of an object, such as a cyclist, from behind. If an object potentially colliding with the side door approaches, the vehicle occupant is warned by a visual or acoustic warning on the inside of the side door.

[0008] Motor vehicles often have a bonnet. In this case, it is common practice, particularly after unlocking the bonnet, to open it manually when desired to open it and to close it again manually when desired to close it. However, solutions have also been proposed to open and / or close bonnets completely automatically. Opening or closing the bonnet in this case can lead to collisions. For example, it is conceivable that the bonnet could be damaged when closing if there is an object left in the engine compartment, such as a forgotten toolbox. However, damage to the bonnet can also occur when opening the bonnet, for example if an obstacle and / or the depth of the ceiling is overlooked.

[0009] DE 101 32 886 A1 relates to a method and a device for opening and closing a part mounted on a vehicle in a rotatable or tiltable manner. Obstacles in the immediate vicinity of the vehicle are to be detected in a timely manner when opening a rotatable or tiltable part, and the part is to be stopped before it collides with an obstacle. Sensors are therefore used to detect obstacles, so that the movement of the part can be stopped or reversed when a minimum distance from the obstacle is reached. The part can be a hood.

[0010] DE 102011 112 684 A1 relates to a motor vehicle with a tailgate that can pivot about a horizontal axis. A sensor of any configuration and configuration is designed to detect an obstacle within the tailgate's pivoting range and prevent the tailgate from pivoting, effectively preventing damage to the tailgate due to an obstacle in the pivoting range. The sensor can be designed as a radar sensor.

[0011] EP 968 863 A1 relates to a vehicle with a tailgate. The tailgate has means for detecting objects, at least during the opening process. If an obstacle is encountered during this opening (or closing) process, either a warning signal (acoustic and / or visual) can be emitted or the further pivoting of the tailgate can be interrupted by suitable means. This effectively prevents the tailgate from colliding with obstacles during the opening or closing process, thus preventing injury to persons and damage to the tailgate, particularly outside.

[0012] DE 198 13 025 A1 discloses a motor vehicle with an outwardly pivoting rear door or flap, in particular a tailgate. To minimize the risk of an automatically opening and / or closing tailgate colliding with an obstacle during its opening or closing movement, the patent proposes arranging distance sensors, preferably in the lower area of ​​the tailgate, and automatically stopping the tailgate when the distance sensors detect an obstacle within a predetermined distance during the opening and / or closing process.

[0013] The invention is therefore based on the object of providing a possibility for improved protection of the bonnet of a motor vehicle with regard to opening and closing operations of the bonnet.

[0014] To achieve this object, the features of claim 1 are provided according to the invention in a motor vehicle of the type mentioned at the outset.

[0015] In addition to the predictive warning during manual operation, it can also be provided that if an obstacle is present in the movement area and if a further action criterion indicating an existing movement of the bonnet is fulfilled, the control device controls the output device to output a warning and / or an actuator assigned to the bonnet to prevent and / or terminate the movement of the bonnet.

[0016] According to the invention, the implementation of a novel driver assistance system, the collision protection system for the hood, is proposed, wherein the opening and closing areas of the hood, i.e., the overall range of movement, can be monitored using radar. Monitoring can take place in both the opening and closing directions, which is preferred. However, it is also conceivable to provide a radar sensor for only one of the directions of movement. In this way, damage to the hood can be largely avoided, particularly during automatic opening and closing processes of the hood, which can be triggered, for example, by a control element on the driver's side. This also applies if manual operation of the hood is intended.If, for example, the bonnet is unlocked, which can be seen as a sign that the bonnet is about to be opened, the radar sensor can be used to check whether there is an obstacle in the area of ​​movement along the opening path of the bonnet. If an obstacle is present, the driver can be warned by issuing a warning. The warning can be issued acoustically and / or visually. However, if the bonnet is open, it can generally be assumed that it will also be closed again, so that appropriate monitoring in the closing direction can take place. In particular, it can therefore be provided that the action criterion indicating an impending movement of the bonnet checks whether the bonnet has been unlocked and / or is open.

[0017] However, the present invention can be particularly advantageously applied to an intended automatic opening and closing of the engine hood, so that an advantageous embodiment of the present invention provides that the actuator comprises a drive device designed to automatically open and close the engine hood, and the control device is designed to monitor the movement area for obstacles in the corresponding direction of movement throughout the entire movement process, provided a radar sensor associated with the direction of movement is present. The drive device can be, for example, an electric motor, which can also be used as an actuator to terminate the movement process or to prevent a movement.Of course, the actuator can also explicitly contain a braking device, for example, a locking device. Such a braking device can also be provided as part of the actuator when used for manual opening and closing operations. If a drive device is present, the entire opening and closing movement can be conveniently monitored, and a collision can be avoided if an obstacle is detected. Conveniently, the actuator can be assigned an operating device for manually triggering a movement of the hood, for example, a switch that enables fully automatic opening and closing, triggered by an operator.

[0018] As already indicated, it is preferred according to the invention if a radar sensor is provided for each direction of movement. This allows both opening and closing processes to be monitored, and collision protection is also provided, particularly with regard to, for example, objects left in the engine compartment that could cause damage to the hood.

[0019] In a specific embodiment of the present invention, it can be provided that at least one of the at least one radar sensor is arranged on the engine hood or integrated therein and / or at least one of the at least one radar sensor is arranged or integrated adjacent to a windshield, in particular on a stationary part of a windshield wiper device. For example, it can be provided that a small-sized radar sensor is placed on the inner side of the engine hood in order to be able to monitor the closing movement. Another small-sized radar sensor can, for example, be provided close to or on a stationary part of a windshield wiper device in order to take over the external monitoring of the engine hood and thus to be able to monitor opening processes. The radar sensor provided for monitoring the opening can of course also be provided on the engine hood or integrated into the engine hood.

[0020] It is preferred if the at least one radar sensor is concealed, in particular installed behind a plastic element. Small-sized radar sensors using semiconductor technology can be concealed in various components or parts of the motor vehicle without requiring a large amount of installation space. The radar sensor is arranged behind a material that is permeable to radar radiation, in particular plastic. In the case of metallic surfaces that are to be penetrated, for example, a radar window can be cut out of this surface and filled with a radar-permeable material, in particular plastic. However, it is preferred if the radar-permeable material, in particular the plastic, is already present. For example, the radar sensor, which is intended to monitor the closing process, can be installed as a plastic element behind an interior trim part of the bonnet.Even stationary parts of the windscreen wiper system and / or protective elements attached to the windscreen are often made of plastic so that a radar sensor can be installed behind them.

[0021] The invention particularly exploits the fact that compact radar sensors embodied in semiconductor technology, preferably CMOS technology, have become known. Thus, an expedient development of the present invention provides that the at least one radar sensor comprises a semiconductor chip, in particular a CMOS chip, that implements a radar transceiver. Further high integration can be achieved by the semiconductor chip also implementing a digital signal processing component of the radar sensor and / or a control unit of the radar sensor and / or by the semiconductor chip and an antenna arrangement of the radar sensor being implemented as a single package. This provides an extremely compact, highly integrated radar sensor that is particularly easy to install in a concealed manner, for example, in the hood or adjacent to the windshield.Nevertheless, the radar data remains of high quality, as the short signal paths in particular allow a high signal-to-noise ratio.

[0022] Since the radar sensor technology used here only needs to address a small range, for example, a maximum range of 3 m, a suitable embodiment of the present invention can provide for the at least one radar sensor to have an antenna arrangement with a size of less than 2 cm x 2 cm and / or for the detection range of the at least one radar sensor to be limited to the extent of the movement area. The detection range can be limited by the control device, which can be implemented in particular as a control unit, controlling the radar sensor with a low transmission power that is matched to the range of the detection range, for example, 3 m.Due to the possibility of using a small antenna arrangement, for example in the range of 1.5cm * 1.5cm, radar concepts with an integrated antenna in the package can be implemented particularly easily, so that the radar sensor can be implemented by an extremely small radar chip, for example a size of 2cm * 2cm * 1cm or less, which simplifies the integration of the radar sensor into the hood and / or other components of the motor vehicle.

[0023] In addition to the motor vehicle, the present invention also relates to a method for operating a collision protection system for a manually operated bonnet of a motor vehicle according to the invention, wherein the control device evaluates the radar data of the radar sensor for obstacles located in the movement area and, if an obstacle is present in the movement area and if an action criterion indicating an impending movement of the bonnet is fulfilled, controls an output device to output a warning as a measure, wherein the action criterion indicating an impending movement of the bonnet checks whether the bonnet has been unlocked and / or is open in order to anticipate a manual movement process. All statements relating to the motor vehicle according to the invention can be transferred analogously to the method according to the invention, with which the advantages already mentioned can therefore also be achieved.

[0024] Further advantages and details of the present invention will become apparent from the exemplary embodiments described below and from the drawings. In the drawings: Fig. 1 a schematic diagram of a motor vehicle according to the invention, and Fig. 2 the construction of a vehicle in accordance with Fig. 1 radar sensor used.

[0025] Fig. Figure 1 shows a schematic diagram of a motor vehicle 1 according to the invention. As is generally known, this motor vehicle has a hood 2, which is shown here in a partially open state for clarity and is pivotally mounted on the body of the motor vehicle. A drive device 3 comprising an electric motor is assigned to the hood 2 as an actuator, via which the hood 2 can automatically open and close, controlled by a control element 4 arranged, for example, in the interior of the motor vehicle 1.

[0026] During an opening process, the hood 2 is typically moved from a first, closed end position 5 to a second, fully open end position 6, and vice versa during a closing process. The area covered in one of these directions between the end positions 5 and 6 during such a movement process forms the movement range 7.

[0027] Obstacles present within the movement area 7, exemplified by obstacle 8, which may be a forgotten toolbox, for example, pose a risk of damage when the hood 2 is opened or closed.

[0028] Therefore, the motor vehicle 1 in the present case has a collision protection system which has radar sensors 9, 10 and a control device 12 implemented as a control unit 11. Both radar sensors 9, 10 are small, in the present case with a size of 2 cm * 2 cm * 0.5 cm, implemented in semiconductor technology, here CMOS technology, whereby Fig. 2 shows a possible design of the radar sensors 9, 10. A circuit board 14 is mounted in a tightly designed housing 13, on which a package 15 is arranged, in which the small antenna array 16 of the radar sensor 9, 10 and a semiconductor chip 17, in this case a CMOS chip, are integrated. The CMOS chip 17 implements not only a radar transceiver 18, but also a digital signal processing component 19 (DSP) and a control unit 20 of the radar sensor.

[0029] Since the detection range of the radar sensors 9, 10 is designed in such a way that it is essentially limited to the detectable parts of the movement area 7, a particularly high range, in particular a range of less than or equal to three meters, is not required, so that not only can the transmission power be kept low, but also a small antenna arrangement 16 can be used, for example with an extension of 1.5 cm * 1.5 cm.

[0030] The radar sensor 9, which is also integrated into the hood 2 under a plastic element 21 as a trim element, is assigned to monitor the movement area 7 for a closing process of the hood 2. Its radar data is therefore evaluated by the control unit 11 when a closing process of the hood 2 is taking place or is about to take place. The radar sensor 10, which in this case is integrated into a fixed part of a windshield wiper device 22 and thus also transmits radiation through the plastic in a concealed manner, is assigned to the opening of the hood 2 as the direction of movement, so that its radar data is evaluated by the control unit 11 when an opening process of the hood 2 is taking place or is about to take place. The imminent opening process can be anticipated, for example, when the hood 2 is unlocked, and the imminent closing process can be anticipated when the hood 2 is open.

[0031] If, in the present exemplary embodiment, it is determined during a movement process by means of the drive device 3 that an obstacle 8 is located in the future movement path, i.e., in the forward portion of the movement area 7, the actuator formed by the drive device 3 is activated to stop this movement and, at the same time, an acoustic and / or visual warning is output via an output device 23 of the motor vehicle 1. In this way, the movement path of the hood 2 is continuously monitored during movements to prevent collisions.

[0032] It should also be noted that, in the case of a manually operated hood, a movement process can preferably be anticipated in the manner described and a warning can be issued accordingly at an early stage; however, manually operated hoods 2 can also have an actuator for braking or preventing a movement.

Claims

[1] Motor vehicle (1), comprising an openable, manually operated bonnet (2) which sweeps over a movement area (7) during an opening process and a closing process, and a collision protection system for the bonnet (2), the collision protection system comprising: - at least one radar sensor (9, 10) associated with a direction of movement, comprising opening and closing, of the bonnet (2), which is arranged to detect at least part of the movement range, at least when the bonnet (2) is not arranged in the end position (5, 6) of the direction of movement, and - a control device (12) which is designed to evaluate the radar data of the radar sensor (9, 10) for obstacles (8) located in the movement area (7), wherein, if an obstacle (8) is present in the movement area (7) and if an action criterion indicating an impending movement of the engine hood (2) is fulfilled, the control device (12) controls an output device for outputting a warning message as a measure, wherein the action criterion indicating an impending movement of the engine hood (2) checks whether the engine hood (2) has been unlocked and / or is open in order to anticipate a manual movement process. [2] Motor vehicle (1) according to claim 1, characterized byin that, for an alternative automatic opening and closing of the engine hood (2), an actuator assigned to the engine hood (2) additionally comprises a drive device (3) designed for automatic opening and closing, and the control device (12) is designed to monitor the movement area (7) for obstacles in the corresponding movement direction over the entire movement process. [3] Motor vehicle (1) according to claim 2, characterized by that the actuator is assigned an operating device (4) for manually triggering a movement process of the bonnet (2). [4] Motor vehicle (1) according to claim 2 or 3, characterized bythat the control device (12) additionally controls the output device for outputting a warning and / or the actuator for preventing and / or terminating the movement of the bonnet (2) when an obstacle (8) is present in the movement area (7) and when a further action criterion indicating an existing movement of the bonnet (2) is fulfilled. [5] Motor vehicle (1) according to one of the preceding claims, characterized by that there is a radar sensor (9, 10) for each direction of movement. [6] Motor vehicle (1) according to one of the preceding claims, characterized by that at least one of the at least one radar sensor (9, 10) is arranged on the engine hood (2) or integrated therein and / or at least one of the at least one radar sensor (9, 10) is arranged or integrated adjacent to a windshield. [7] Motor vehicle (1) according to one of the preceding claims, characterized bythat at least one radar sensor (9, 10) is installed in a concealed manner. [8] Motor vehicle (1) according to one of the preceding claims, characterized by that the at least one radar sensor (9, 10) has a semiconductor chip (17) implementing a radar transceiver (18). [9] Motor vehicle (1) according to claim 8, characterized by that a digital signal processing component (19) of the radar sensor (9, 10) and / or a control unit (20) of the radar sensor (9, 10) are also realized by the semiconductor chip (17) and / or the semiconductor chip (17) and an antenna arrangement (16) of the radar sensor (9, 10) are realized as a package (15). [10] Motor vehicle (1) according to one of the preceding claims, characterized bythat the at least one radar sensor (9, 10) has an antenna arrangement with a size of less than 2 cm by 2 cm and / or the detection range of the at least one radar sensor (9, 10) is limited in its range to the extent of the movement range (7). [11] Method for operating a collision protection system for a manually operated bonnet (2) of a motor vehicle (1) according to one of the preceding claims, wherein the control device (12) evaluates the radar data of the radar sensor (9, 10) for obstacles (8) located in the movement area (7) and, if an obstacle (8) is present in the movement area (7) and if an action criterion indicating an impending movement of the bonnet (2) is fulfilled, controls an output device for outputting a warning as a measure, wherein the action criterion indicating an impending movement of the bonnet (2) checks whether the bonnet (2) has been unlocked and / or is open in order to anticipate a manual movement process.

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