Motor vehicle having a vehicle flap which can be adjusted in a contactless manner by means of a radar sensor

Abstract

The invention relates to a motor vehicle (1) having a vehicle flap which can be adjusted in a contactless manner. The motor vehicle has a control system, a radar sensor (8), a control circuit (12) and an electric motor. The control circuit (12) is configured to control the electric motor on the basis of signals, detected by the radar sensor (8), of a kick gesture carried out within a detection space. In the approach detection mode, an operator (5) approaches the rough detection space (9'). A combination of the position in the region (A) and the angle of arrival (α) is evaluated. In the present example, the radar sensor has an adjustability between two different fields-of-view, specifically the field-of-view (FOV1) and the field-of-view (FOV2).

Description

[0001] H01512

[0002] CK

[0003] Motor vehicle with a contactless adjustable

[0004] Vehicle hatch

[0005] The invention relates to a motor vehicle with a contactless adjustable vehicle flap.

[0006] To provide functionality, the motor vehicle has a control system.

[0007] The functionality of a control system of this type is based on acquiring sensor data with a radar sensor to detect a control gesture performed within the radar sensor's detection range. This gesture is then used to issue a trigger signal to initiate the adjustment of a vehicle flap on a motor vehicle.

[0008] The principle of radar technology has been known since the early 20th century. Radar technology utilizes the idea of ​​emitting electromagnetic waves, receiving the echo (the reflected waves, also known as the radar response), and then evaluating the received reflected waves according to specific criteria. Depending on the specific implementation, radar technology can provide various pieces of information about objects where the echo is generated by reflecting the emitted waves. For example, radar technology can be used to locate an object. Furthermore, information about the relative motion between the sensor and the reflecting object can be obtained, for example, by utilizing the Doppler effect.Information about the absolute velocity of the object can also be derived, as well as, alternatively or additionally, information about the contours of the reflecting object.

[0009] The use of radar technology is becoming increasingly important in automotive engineering. One reason for this is the desire to increase vehicle autonomy, which has driven the further development of radar sensors for use in vehicles. This development has led, among other things, to radar sensors suitable for equipping vehicles becoming available as ready-to-install, relatively inexpensive systems. This has enabled their use in a wide range of applications in series production models in an economically viable way. With the help of commercially available radar sensors, object detection with a high degree of lateral range and both lateral and angular resolution can be achieved for the operation of a motor vehicle. Where required, good temporal resolution of the data acquired by radar sensors is also attainable.

[0010] The use of radar sensors has the advantage that, due to their fundamental operating principle of utilizing a radar response to acquire information, they can obtain information that goes beyond what can be achieved with ultrasonic sensors. Compared to lidar systems, which are also generally suitable for acquiring high-quality sensor data, radar sensors often have the decisive advantage for mass-market applications of being more cost-effective.

[0011] When designing sensor systems for motor vehicles, there is also a desire for radar sensors to make gesture recognition as efficient as possible, and in particular to keep the number of required sensors to a minimum without compromising the reliability of the recognition. Against this background, the task is to contribute to increasing the efficiency of gesture recognition while maintaining good recognition accuracy.

[0012] This problem is solved with a motor vehicle having the features of claim 1.

[0013] A motor vehicle is provided that has a contactless adjustable tailgate. To provide this functionality, the motor vehicle has a control system for contactless adjustment of the tailgate.

[0014] The vehicle's control system includes a radar sensor. This radar sensor can operate in the frequency range around 24 GHz, for example, between 23 and 25 GHz, preferably between 24.00 GHz and 24.25 GHz; in the frequency range around 60 GHz, for example, between 59 and 61 GHz; or in the frequency range between 77 GHz and 81 GHz. These frequency ranges are commonly used in commercially available radar sensors, due in part to regulatory and electromagnetic compatibility requirements. Radar sensors in these frequency ranges are sometimes referred to as "nunwave" in English, based on the wavelength of the emitted electromagnetic waves.

[0015] The control system features an electric motor that is coupled or can be coupled to the vehicle's tailgate.

[0016] According to the invention, a control circuit is coupled to the radar sensor and the electric motor. The control circuit is configured to control the radar sensor and process its signals.

[0017] The control circuit is designed to control the electric motor with a trigger signal to adjust the vehicle flap of the motor vehicle, depending on signals detected by the radar sensor and a control gesture, in particular a kick gesture, performed within a detection area of ​​the radar sensor.

[0018] The radar sensor and the control circuit are configured to adjust parameters, particularly transmit and / or receive parameters, of the radar sensor to change its field of view. This means that the field of view covered by the radar sensor can be modified by selecting parameters from a number of options on the control circuit, depending on the intended use. For example, a radar sensor may have multiple transmitting antennas, such as three, and the field of view may be changed solely by selecting one of the three antennas. Alternatively, the field of view may be changed not only by adjusting one or more other parameters but also by selecting one of the three antennas.

[0019] The radar sensor and the control circuit are set up alternatively or additionally to adjust parameters, in particular evaluation parameters, of the radar sensor to change the evaluated portion of the field-of-view of the radar sensor.

[0020] The radar sensor and the control circuit are set up alternatively or additionally to adjust parameters, especially chirp parameters, of the radar sensor to adapt the evaluation behavior of the radar sensor.

[0021] The control circuit is configured to switch the radar sensor between operation in proximity detection mode and operation in gesture detection mode. The proximity detection mode is configured to...

[0022] To detect the approach of an operator or potential operator, the proximity detection system may, among other things, operate the radar sensor with a low polling frequency, for example, with a polling interval between 1 and 60 seconds. Furthermore, it may be designed so that the radar sensor operates with reduced energy consumption in proximity detection mode, which can be achieved, for example, by activating a subset of the available transmitting antennas, such as only one of the three available transmitting antennas.

[0023] The control circuit is configured, in proximity detection mode, to perform a two-step sequence of actions in response to the detected approach of an object, for example an operator, within a space detected in proximity detection mode, which is referred to as the coarse detection area of ​​the radar sensor:

[0024] As a first step, an evaluation of the object's position information is carried out.

[0025] In a second step, depending on the position information, a transmit parameter and / or a receive parameter and / or an evaluation parameter and / or a chirp parameter of the radar sensor is set to change the gesture recognition of a kick gesture, which is performed in the then set field-of-view, which is referred to as the gesture detection area, in the gesture recognition mode.

[0026] For example, in an advantageous further training, this is implemented by setting a transmit parameter and / or a receive parameter of the radar sensor in the second step, depending on the position information, to change the field-of-view for the gesture recognition of a kick gesture, which is performed in the then set field-of-view, which is called the gesture detection area, in the gesture recognition mode.

[0027] One aspect of the present invention is therefore to adjust the field of view of the radar sensor based on parameters, wherein the parameter adjustment is performed depending on position information of the detected object. Thus, initial information obtained about an object, which could be, for example, a vehicle user, is used as the basis for adjusting a field of view that can be modified by means of a control circuit. This approach can be advantageously used, for example, to restrict the field of view to an area where the gesture is more likely to be performed than in other areas, and where, consequently, data acquisition for gesture recognition is more likely to occur.

[0028] The essential idea underlying this concept is that the area to be covered by the radar sensor is adjusted based on initial information acquired by the radar sensor. This approach advantageously allows for optimized gesture recognition, for example, with regard to energy efficiency, temporal resolution, lateral resolution, angular resolution, or a combination of several or all of the aforementioned.

[0029] For setting the field of view and the dependence of this setting on position information, the use of empirically obtained data stored on a memory device of the control circuit or a memory device coupled to the control circuit can be provided for. According to a further development, the position information can be the distance of the object from the radar sensor. Alternatively, the position information can be the angle of arrival of the object at the radar sensor or at a plane in a fixed ratio to the radar sensor. Alternatively or additionally, the position information can be a quantity that depends on one or both of the aforementioned quantities.

[0030] For example, it can be provided that, prior to the provision of the vehicle according to the invention, a set of position information is empirically collected and gesture recognitions are performed depending on this set of position information. Then, as desired, a parameter or set of parameters for setting the field of view is defined for the set of position information and stored on the storage medium in association with the respective position information. This can be used to utilize the position information obtained according to the invention, after referencing its association with the parameter or set of parameters, to set the field of view for the gesture recognition expected after receiving the position information, in particular a kick gesture.

[0031] It may therefore be provided that the control device or a storage medium coupled with the control device contains empirically obtained data that includes a number of mappings from one or more pieces of position information to parameters for changing the field of view.

[0032] According to a further training course, it is particularly preferred that the change of the field of view be considered as

[0033] The reduction of the field of view is performed to

[0034] Coverage of an area, determined from position information as the likely execution area of ​​a kick gesture, that can be covered by the radar sensor. This can be achieved, for example, by selecting one transmitting antenna from a total of three available transmitting antennas, selecting the one that covers the field of view where a kick gesture is expected. This expectation is based, in particular, on the empirical studies mentioned above, so that the transmitting antenna to be selected depends on the position information and the associated data stored within it.

[0035] Particularly preferred is that the radar sensor has at least two transmitting antennas, preferably exactly two, wherein a change in the field of view also results in a change in the number of transmitted antennas being used. For example, as mentioned above, the selection of one of the transmitting antennas from the at least two, preferably exactly two, transmitting antennas can be carried out depending on the position information obtained.

[0036] Overall, the system is designed to achieve an optimized beam pattern after an initial coarse detection based on position information, enabling the reliable detection of anticipated gestures, particularly kicking gestures. This could involve, for example, creating trapezoidal detection zones on the ground to recognize kicking gestures. A key aspect of this development is to adjust the detection zone through parameterized control of the radar sensor. This allows for precise adjustment of the detection zone based on the initial position or movement detection.

[0037] User recognition, or a combination of both, can be carried out in a particularly advantageous manner. Not least, recognition can also be taken into account in recognition areas that are not located, or not only located, below the vehicle; rather, recognition areas located in front of or behind the vehicle can also be considered, particularly for the recognition of kick gestures.

[0038] According to an advantageous embodiment, the control circuit is configured to evaluate the signals from the radar sensor in order to detect, in gesture recognition mode, the execution of the control gesture, performed as a kick gesture, within the detection area. The response signals, which the radar sensor receives from the reflections of the emitted radar waves, are compared by the control circuit with a set of predefined control gesture criteria, where the control gesture criteria are also referred to as kick gesture criteria, i.e., one or more predefined control gesture criteria. The trigger signal is output by the control circuit only, preferably, if and when the control gesture fulfills all predefined control gesture criteria or a required subset of the set of predefined control gesture criteria. Otherwise, the control gesture is rejected as an incorrect operation.

[0039] It is therefore stipulated that, at least for the output of the trigger signal, the necessary, preferably sufficient, condition has been established as fulfilled: that the control gesture fulfills all predefined control gesture criteria of the set of predefined control gesture criteria or, in an alternative implementation, a required subset of the set of predefined control gesture criteria. Optionally, for the possible output of a trigger signal, the additional condition may be required that further fulfillment criteria have been met, for example, further requirements regarding the

[0040] The execution of the control gesture and / or other operating patterns performed on the control device, such as the detection of the presence of an ID transmitter in the vicinity of the control system. In a specific implementation, it may be provided that the determination that the control gesture has fulfilled all predefined control gesture criteria or a required subset of the set of predefined control gesture criteria is a sufficient condition for the output of the trigger signal.

[0041] By specifying that, in addition to checking the radar sensor signals against a kick gesture criterion, recognition in gesture detection mode takes place in a field-of-view that has been pre-defined based on the position information obtained in proximity detection mode, data with very good spatial and / or temporal resolution is available for checking the radar sensor signals against the kick gesture criterion, so that, in combination with the measures taken, a data evaluation with high recognition accuracy can be obtained.

[0042] According to a further development of the motor vehicle according to the invention, one of the predefined control gesture criteria can be configured as an orientation criterion concerning the direction of movement of the object performing the control gesture. The object performing the control gesture, for example, an operator's foot or leg, has a specific orientation when the control gesture is executed. For example, if the object is a foot, a longitudinal axis of the foot may have a specific orientation when the control gesture is executed. According to this further development, the direction of movement exhibited by the object when the control gesture is executed is now considered as a control gesture criterion or as part of the control gesture criterion.For example, the alignment criterion can be the orientation of the object performing the control gesture when it encounters a predefined plane located within the radar sensor's detection range. Modern radar sensors are capable of measuring not only speed but also the direction of movement, and the control circuitry is able to derive appropriate consequences from this direction. By allowing the triggering of a signal only when one of the control gesture criteria, configured as an alignment criterion, is met by the control gesture, the accuracy of gesture recognition can be increased, and an improved distinction between erroneous and intended actions can be achieved.

[0043] According to a preferred further development, the control circuit can be configured to output the trigger signal only if the control gesture, executed as a kick gesture, fulfills the alignment criterion, and otherwise to discard the control gesture as an incorrect operation. In this case, fulfilling the alignment criterion is therefore a necessary condition for outputting the trigger signal. Considering the alignment criterion means that even if a control gesture includes further control gesture criteria, an otherwise correct execution of the control gesture will not trigger the trigger signal if only the alignment criterion is not met. For example, an unintentionally executed gesture that happens to correspond to the control gesture and thereby fulfills all control gesture criteria (also referred to analogously as kick gesture criteria) would, apart from the

[0044] The alignment criterion is fulfilled, and if, due to the measure provided according to the invention of checking the alignment of the object during execution of the control gesture, it is identified as an operating error and can then be rejected as such.

[0045] One approach involves providing several alignment criteria, and configuring the control circuit to issue the trigger signal only when the control gesture meets all alignment criteria, otherwise rejecting the control gesture as an operator error. This variant can increase the safety of the procedure.

[0046] One approach involves providing a number of alignment criteria, and configuring the control circuit to output the trigger signal only if the control gesture fulfills at least one subset of the alignment criteria, otherwise discarding the control gesture as an operator error. This approach avoids excessively frequent discarding as an operator error. The subset to be fulfilled can be defined as a minimum number of alignment criteria, which may otherwise be met arbitrarily; alternatively, the subset to be fulfilled can be defined as one of one or more predefined permissible combinations of a subset of the alignment criteria.

[0047] The alignment criterion regarding the direction of movement can, for example, be set as the criterion that the arrival angle of the object performing the control gesture is detected as lying within a target range. The arrival angle can, for example, be the arrival angle relative to a reference plane that lies within the detection range of the radar sensor.For example, in a case where the control system is arranged in a motor vehicle and the radar sensor is arranged in a rear bumper of the motor vehicle in order to monitor kick gestures with an orientation of the detection area pointing from the bumper towards the ground, it can be provided that the direction of movement of the object, for example a human foot, is in a longitudinal direction of the motor vehicle, i.e. the direction in which the motor vehicle can move in a straight line, or deviates from this longitudinal direction by a maximum angle of deviation + / - alpha, where alpha is, for example, 45°, preferably 20°, particularly preferably 10°, whereby in particular a symmetrical deviation of the arrival angle when projected onto a plane parallel to the plane of movement of the vehicle by the angle alpha can form the target range.It may therefore be provided that, for example, the trigger signal is rejected as an operating error if the object performing the control gesture deviates by more than the angle alpha from a plane that is the symmetry plane of the vehicle or a plane of the vehicle parallel to this symmetry plane. In particular, it may be provided that, for example, the trigger signal is rejected as an operating error if the object performing the control gesture, upon reaching a reference plane defined in the control circuit within the detection area and intersected perpendicularly by the straight-line direction of travel of the vehicle, deviates by more than the angle alpha from a plane that is the symmetry plane of the vehicle or a plane of the vehicle parallel to this symmetry plane.

[0048] Furthermore, according to a particularly preferred embodiment, the control circuit may be configured to block the output of the control signal for a predetermined blocking period if the control gesture

[0049] The alignment criterion is not met, for example, if the arrival angle is detected as lying outside the target range. This means that if a gesture is detected and rejected as an incorrect operation, further gestures will initially not be recognized as valid, or at least will not trigger the release signal. This measure is based on the consideration that incorrect operation occurs in situations where further incorrect operation is likely and where it can also be assumed that the correct control gesture, including fulfillment of the alignment criterion, is more likely than average. Such situations can arise, for example, when the vehicle is positioned in a dense crowd.To avoid situations where the accidental execution of the correct control gesture is more likely than average, where the trigger signal is issued without intended or authorized access to the vehicle, the measure of temporary locking during the specified locking period was devised to reduce the proportion of false triggers among the issued trigger signals.

[0050] When the arrival angle is mentioned, this refers, for example, to the arrival angle of the trajectory of the geometric center of gravity of the object performing the control gesture, as determined in the control circuit.

[0051] For example, it may be provided that the blocking period is greater than 1 second, preferably greater than 5 seconds, and most preferably greater than 10 seconds.

[0052] Alternatively or additionally, it may be provided that the blocking period is less than 60 seconds, preferably less than 30 seconds, and particularly preferably less than 20 seconds.

[0053] Furthermore, according to a particularly preferred embodiment, it may alternatively or additionally be provided that the control circuit is configured to reduce the target range for the arrival angle of the object performing the control gesture for a predetermined temporary period if the control gesture does not meet the alignment criterion. Thus, if, for example, it is normally provided that the trigger signal is discarded as an operator error if the object performing the control gesture deviates by more than the angle alpha from a plane that is the symmetry plane of the vehicle or a plane of the vehicle parallel to this symmetry plane, the angle alpha can be changed to an angle beta, where beta is smaller than alpha, upon detection of an operator error.This increases the requirements for the accuracy of the input gesture, thus reducing the risk of accidental or malicious false triggers for a temporary period, even at the cost of reduced user comfort.

[0054] Particularly preferred according to an advantageous embodiment is that a further of the specified control gesture criteria is designed as a switchable detection criterion. The detection criterion relates to a property of a sensor gesture detectable by the radar sensor, for example, the velocity of the object performing the sensor gesture, the lateral extent of the object performing the sensor gesture, or the trajectory traveled by the object performing the sensor gesture when executing the sensor gesture.

[0055] In this advanced training, the control circuit is configured to only output the trigger signal if the control gesture meets the detection criterion, and otherwise to reject the control gesture as an incorrect operation.

[0056] For example, in one implementation it may be stipulated that a necessary condition for the output of the trigger signal is that the control gesture satisfies both the alignment criterion and the detection criterion. In a specific implementation, it may even be stipulated that a sufficient condition for the output of the trigger signal is that the control gesture satisfies both the alignment criterion and the detection criterion.

[0057] Regardless of the specific implementation, the detection criterion can have a first sensitivity level and a second sensitivity level. It is intended that the detection criterion normally assumes the first sensitivity level, but it switches from the first to the second sensitivity level if the control gesture does not meet the alignment criterion, for example, if the arrival angle is detected as being outside the target range. The detection criterion is specifically switched from the first to the second sensitivity level after it has been determined that the control gesture does not meet the alignment criterion, and thus as an immediate and instantaneous reaction to this determination.By allowing the sensitivity level to be adjusted, a second sensitivity level can be determined professionally, for example empirically, so that after a control gesture is rejected as an error, subsequent control gestures require higher levels of precision to trigger the release signal. The expert can, for example, use empirical methods to select values ​​for the first and second sensitivity levels that are deemed advantageous for realistically assumed application scenarios of the control system. For instance, the detection criterion could be designed to recognize that the speed of the object performing the control gesture is within a defined range.For example, the detection criterion can consist of the speed of the object performing the control gesture being detected as lying within a target range when it reaches a predefined plane, for example a reference plane located within the detection space and defined in the control circuit, which is intersected perpendicularly by the straight-line direction of travel of the vehicle.

[0058] Accordingly, the change in the sensitivity of the detection criterion can be implemented, for example, as follows: the control system can be configured such that the target range for the first sensitivity lies between vl_lower and vl_upper, whereas for the second sensitivity, the target range lies between v2_lower and v2_upper. For example, v2_lower > vl_lower and / or v2_upper < vl_upper can be defined. In the preceding representation, vl_lower, v2_lower, vl_upper, and v2_upper each denote scalar absolute values ​​for velocities in the same unit, for example, meters per second.In this implementation, this means that if the arrival angle is detected as being outside the target range, resulting in the rejection of the control gesture as an error, the permissible speed range of the object performing the control gesture—for example, the speed upon arrival at a hypothetical plane, particularly the plane described above, with respect to which the arrival angle is also defined—is narrowed. Specifically, it is narrowed from the initial, standard range vl_lower to vl_upper to the narrower range v2_lower to v2_upper. This measure ensures that, following a gesture detection deemed an error, the system's tolerance for the execution of the control gesture and its recognition as permissible is reduced.

[0059] The control gesture is reduced. This reduces the probability of accidental triggers, which are unintended or unauthorized, for subsequent gesture detection attempts.

[0060] For example, it may be provided that if the detection criterion assumes the second sensitivity level, it is switched back to the first sensitivity level after a predetermined uninterrupted detection-free period has elapsed without any control gesture being detected. Alternatively or additionally, it can be switched back to the first sensitivity level immediately, and preferably without delay, after the trigger signal has been issued.This means that one or more criteria are defined, which ensure that the default initial sensitivity level is restored after a certain period of time. This restoration can be based on either the passage of time, the fulfillment of the correct gesture even with a higher accuracy requirement, a combination of both, or a combination of one or both with further conditions. This ensures that narrowing the sensitivity level to a more demanding evaluation is only temporary and limited to situations where it is deemed necessary, for example, to ensure operational safety. Once this situation is considered resolved, the temporary state is reset to the default setting, which improves user-friendliness.

[0061] According to a particularly preferred embodiment, the radar sensor has a field of view with an azimuth angle of at least 100 degrees and an elevation angle of at least 60 degrees, wherein, preferably in approach detection mode, the radar sensor is configured to cover a field of view with an azimuth angle of at least 100 degrees and an elevation angle of at least 60 degrees. Once position information has been acquired in approach detection mode, the field of view, or alternatively the evaluated sub-area of ​​the field of view, can then be restricted to a narrower area in order to limit it to the space for which gesture recognition is considered potentially necessary based on empirical data.

[0062] The vehicle preferably features a radar sensor as its sole kick sensor for detecting a kick gesture performed behind the vehicle. By using a radar sensor with a comparatively comprehensive field of view in such a way that the field of view is optimized based on initial information, sufficiently good results can be obtained using only one radar sensor. This offers advantages in cost-efficiency and contradicts previous expectations.

[0063] Further details, features and advantages of the control system according to the invention will become apparent from the following description in conjunction with the figures, in which exemplary embodiments of the invention are shown.

[0064] It is understood that the features mentioned above, as well as those explained below, can be used not only in the combination specified, but also in other combinations or on their own.

[0065] They show:

[0066] Fig. 1: a basic configuration of a motor vehicle with an embodiment according to the invention;

[0067] Fig. 2: an application of the motor vehicle according to the invention;

[0068] Fig. 3: Flowchart illustrating a process as can be carried out in the application of Fig. 2;

[0069] Fig. 4: a flowchart of steps to illustrate a further embodiment of an inventive control system;

[0070] Fig. 5: a flowchart of step sequences to illustrate a further embodiment of a control system according to the invention.

[0071] Figure 1 shows a motor vehicle 1 which has a control system 4 according to the invention. The control system 4 is configured to adjust a vehicle flap 2, for example the trunk lid, of the motor vehicle 1 without physical contact. Alternatively, by appropriately arranging the radar sensor, it is also possible to control a flap located at the front of the vehicle, for example an engine compartment lid or, for example in the case of sports cars with a trunk lid located at the front, a front trunk lid.

[0072] In order to provide suitable sensors for contactless adjustment, the control system 4 has a radar sensor 8 which is arranged in a rear bumper 7 of the motor vehicle 1, with an orientation of the detection area 9 pointing from the bumper 7 towards the ground and from the motor vehicle 1 antiparallel to the direction of travel, so that the detection area can be entered by an operator 5 directed from behind the vehicle towards the vehicle flap by means of a control gesture performed as a kicking movement 11.

[0073] The control system 4 also includes an electric motor 6 which can be coupled or connected to the vehicle flap 2 to cause the adjustment of the vehicle flap 2 upon output of a trigger signal.

[0074] A control circuit 12, 13 is coupled to the radar sensor 8 and the electric motor 6. The control circuit 12 is configured to control the radar sensor 8 and process its signals. Depending on signals detected by the radar sensor 8 and a control gesture 11 performed by an operator 5 within the detection range 9 of the radar sensor 8, the control circuit 12 activates the electric motor 6 with the trigger signal, whereupon the adjustment of the vehicle flap 2 of the vehicle 1 is initiated.

[0075] The control circuit 12, which may be, for example, a microcontroller or part of the central vehicle control system, is set up to evaluate radar signals detected by the radar sensor 8 in order to recognize the execution of the control gesture in the detection area.

[0076] In the control circuit 8, a reference plane 13 is defined within the detection area, i.e., it at least partially traverses this area. This reference plane is intersected perpendicularly by the straight-line direction of travel 14 of the vehicle, and against which, for example, an alignment criterion and / or a detection criterion can be checked. It can be provided that the alignment criterion and / or the detection criterion is checked when the object performing the control gesture reaches the reference plane 13.

[0077] Figure 2 shows an application of the motor vehicle 1 according to the invention in a top-down view. In proximity detection mode, an operator 5 approaches the coarse detection area 9', and the radar sensor detects the approach (S1). In a next step, the control circuit performs an evaluation of the object's position information; that is, it determines the position information from the location and / or movement of the operator 5 (S2). The result, in this case, is a combination of the position in area A and the arrival angle alpha. In this example, the radar sensor has a switchable field-of-view capability, namely field-of-view FOV1 and field-of-view FOV2.

[0078] Based on previously collected empirical data and its storage on a control device coupled to the radar sensor, the radar sensor is able to determine that, based on the movement detected in the proximity detection mode, a selection of FOV2 should be made (S3). Radar sensor 8 and control circuit 12 are configured to select FOV2 by setting corresponding transmit and / or receive parameters and then switch to gesture detection mode (S4).

[0079] The steps SI, S2, S3 and S4 mentioned above are shown in Fig. 3.

[0080] A possible implementation of the evaluation of signals from a kick gesture in gesture recognition mode is schematically illustrated in Fig. 4. The gesture recognition mode accordingly captures data representing a kick gesture, which, for example, has been obtained within the field of view using the method described in Figs. 2 and 3. In a first step, the control circuit compares the control gesture, represented by measurement parameters, with a set of predefined parameters.

[0081] Control gesture criteria. It is specified that the trigger signal is only issued if the control gesture fulfills a required subset of a predefined number (two in the example shown) of the predefined control gesture criteria, and that otherwise the control gesture is rejected as an incorrect operation. In the example shown, it is also specified as a special case that the trigger signal is issued precisely if the control gesture fulfills a required subset of a predefined number (two in the example shown) of the predefined control gesture criteria, where the required subset of the predefined number in the example shown is not arbitrary, but must fulfill a further condition:

[0082] One of the predefined control gesture criteria is configured as alignment criterion A, concerning the direction of movement of the object performing the control gesture. The control circuit is configured to output the trigger signal (necessary condition) only if the control gesture fulfills the alignment criterion, and otherwise to reject the control gesture as an incorrect operation.

[0083] In the example shown, the alignment criterion regarding the direction of movement consists of checking whether the arrival angle of the object performing the control gesture is detected as lying within a target range. This check is performed in step 100. If criterion condition A is met, step 200 checks whether at least two of the criteria are fulfilled by the control gesture. If this is the case, then the trigger signal is output in step 300.

[0084] In the event that step 100 detects that the arrival angle lies outside the target range, the output of the control signal is blocked for a predefined blocking period t_S. Figure 5 shows another embodiment. The embodiment in Figure 5 provides that one of the predefined control gesture criteria, preferably not the alignment criterion, is configured as a switchable detection criterion. The detection criterion has a first sensitivity level and a second sensitivity level. If the detection criterion is set to the first sensitivity level, it is switched from the first sensitivity level to the second sensitivity level if the control gesture does not meet the alignment criterion, i.e., in this example, if the arrival angle is detected as lying outside the target range.

[0085] As in the example described in Fig. 4, the alignment criterion regarding the direction of movement in the example shown consists of checking whether the arrival angle of the object performing the control gesture is detected as lying within a target range. This check is performed in step 100. If condition A is met, step 200 checks whether, in addition to criterion A, the detection criterion is also met. If this is the case, the trigger signal is output in step 300.

[0086] If, in step 100, the check reveals that the control gesture does not meet the alignment criterion, i.e., the arrival angle is outside the target range, then the detection criterion is changed from the first sensitivity measure to the second sensitivity measure.

[0087] In the example shown, the detection criterion is defined as follows: if the speed of the object performing the control gesture is detected as lying within a target range, that is: if the speed lies outside this target range, i.e., is smaller or larger, the control circuit for checking the

[0088] The detection criterion was switched from the first sensitivity measure to the second sensitivity measure.

[0089] The first sensitivity measure comprises a target range [vl_lower ; vl_upper ] and the second sensitivity measure a target range [v2_lower ; v2_upper ] , where the second interval in this example lies completely within the first interval ; by changing the sensitivity measure, the effect is that for a renewed attempt to trigger the output signal by performing the control gesture, higher requirements are placed on the accuracy of the control gesture, since the bandwidth of permissible speeds has become narrower .

[0090] After a predetermined, uninterrupted period without detection has elapsed, during which no control gesture has been recognized, the system can revert to the original sensitivity level, for example, after a period of at least 5 minutes. Longer periods are also possible, such as a period of at least 6 hours. Alternatively or additionally, the system can revert to the first sensitivity level immediately after the trigger signal is issued, as in such a situation a control gesture has been recognized as permissible under the more demanding conditions of the second sensitivity level. Therefore, for further triggers, the default requirements of the second sensitivity level can again be considered sufficient.

Claims

H01512 CK Patentansprüche 1. Motor vehicle (1) with a contactless adjustable vehicle flap (2), the motor vehicle (1) comprising a control system (4) for contactless adjustment of the vehicle flap (2) of the motor vehicle (1), the control system (4) comprising a radar sensor (8), a control circuit (12) coupled to the radar sensor (8), an electric motor coupled to the control circuit (12) and capable of being coupled or coupled to the vehicle flap (2), wherein the control circuit (12) is configured to control the radar sensor (8) and process its signals, wherein the control circuit (12) is configured, depending on signals detected by the radar sensor (8) of a kick gesture (11) performed within a detection area (9) of the radar sensor (8), to control the electric motor (6) with a trigger signal for adjusting the vehicle flap (2) of the motor vehicle (1), wherein the radar sensor (8) and the control circuit (12) are configured are parameters,in particular to adjust transmit and / or receive parameters of the radar sensor to change the field of view of the radar sensor, and / or the radar sensor (8) and the control circuit (12) are set up, to adjust parameters, in particular evaluation parameters, of the radar sensor to change the evaluated portion of the field of view of the radar sensor and / or, the radar sensor (8) and the control circuit (12) are configured to set parameters, in particular chirp parameters, of the radar sensor to adapt the evaluation behavior of the radar sensor, wherein the control circuit (12) is configured to switch the radar sensor between operation in proximity detection mode and operation in gesture detection mode, wherein the control circuit (12) is configured, in proximity detection mode, upon detection of the approach of an object, for example an operator, within a coarse detection area (9) of the radar sensor (8), in response to the approach of the object, to first perform an evaluation of position information of the object, and in a second step, depending on the position information, to adjust the parameters, in particular transmit parameters and / or receive parameters and / or evaluation parameters and / or chirp parameters.to adjust the radar sensor to change the gesture recognition in the gesture recognition mode of a kick gesture performed in a gesture detection room ( 11 )., 2. Motor vehicle according to claim 1, wherein the radar sensor (8) and the control circuit (12) are configured to adjust transmit parameters and / or receive parameters of the radar sensor to change the field of view of the radar sensor, and in the second step, depending on the position information, to adjust the transmit parameters and / or receive parameters of the radar sensor to change the field of view for gesture recognition in the gesture recognition mode of a kick gesture (11) performed in a gesture detection space.

3. Motor vehicle (1) according to claim 1 or according to claim 2 wherein the position information is a distance, or the position information is an angle of arrival, or the position information is a quantity dependent on one or both of the aforementioned.

4. Motor vehicle (1) according to one of the preceding claims, wherein the control circuit is configured to execute the change of the field-of-view as a reduction of the field-of-view to cover a probable execution space of a kick gesture derived from the position information.

5. Motor vehicle (1) according to one of the preceding claims, wherein the radar sensor has a number of at least two transmitting antennas, wherein a change in the field of view also includes at least a change in the number of the controlled transmitting antennas.

6. Motor vehicle (1) according to one of the preceding claims, wherein empirically obtained data are stored on the control device or on a storage medium coupled to the control device, comprising a number of assignments from one or more position information to parameters for changing the field of view.

7. Motor vehicle (1) according to one of the preceding claims, wherein the control circuit (12) is configured to evaluate the signals of the radar sensor (8) in order to detect the execution of the kick gesture (11) in the detection area (9), to compare the kick gesture (11) with a set of predetermined kick gesture criteria, and to trigger the trigger signal only to output if the kick gesture (11) fulfills all specified kick gesture criteria or a required subset of the set of specified kick gesture criteria, and otherwise to reject the kick gesture as an incorrect operation, wherein one of the specified kick gesture criteria is designed as an orientation criterion concerning the direction of movement of the object performing the kick gesture (11) when performing the kick gesture (11).

8. Motor vehicle (1) according to one of the preceding claims, wherein the control circuit (12) is configured to output the trigger signal only if the kick gesture (11) meets the alignment criterion, and otherwise to reject the kick gesture (11) as an incorrect operation.

9. Motor vehicle (1) according to one of the preceding claims, wherein the alignment criterion relating to the direction of movement consists in the fact that an arrival angle of the object performing the kick gesture (11) is detected as lying within a target range.

10. Motor vehicle (1) according to one of the preceding claims, characterized in that the control circuit (12) is configured to block the output of the control signal for a predetermined blocking period if the kick gesture does not meet the alignment criterion and / or that the control circuit (12) is configured to block the output of the control signal for a predetermined temporary period as the target range for the arrival angle of the object performing the kick gesture (11) to reduce in size if the kick gesture (11) does not meet the alignment criterion.

11. Motor vehicle (1) according to claim 10, characterized in that the blocking period is greater than 1 second, preferably greater than 5 seconds, particularly preferably greater than 10 seconds, and / or that the blocking period is less than 60 seconds, preferably less than 30 seconds, particularly preferably less than 20 seconds.

12. Motor vehicle (1) according to one of claims 7 to 11, characterized in that a further of the predetermined kick gesture criteria is designed as a switchable detection criterion, wherein the control circuit is configured to output the trigger signal only if the kick gesture fulfills the detection criterion, and otherwise to reject the kick gesture as an incorrect operation, wherein the detection criterion is a first can assume a sensitivity measure and a second sensitivity measure, whereby if the detection criterion assumes the first sensitivity measure, the detection criterion is switched from the first sensitivity measure to the second sensitivity measure if the kick gesture does not meet the alignment criterion.

13. Motor vehicle (1) according to claim 12, characterized in that the detection criterion consists in the detection of a speed of the object performing the kick gesture lying within a target range.

14. Motor vehicle ( 1 ) according to claim 13 , characterized in that in the first sensitivity measure the target range lies between vl_lower and vl_upper , that in the second sensitivity measure the target range lies between v2_lower and v2_upper , wherein 2_lower > vl_lower and / or wherein v2_upper < vl_upper .

15. Motor vehicle ( 1 ) according to one of claims 12 to 14 , characterized in that the detection criterion, when it assumes the second sensitivity level, is switched to the first sensitivity level after a predetermined uninterrupted detection-free period has elapsed without the execution of a kick gesture being detected, and / or it is switched to the first sensitivity level immediately after the trigger signal has been issued .

16. Motor vehicle ( 1 ) according to one of the preceding claims, wherein the radar sensor has a field-of-view with an azimuth angle of at least 100 degrees and an elevation angle of at least 60 degrees, and preferably in the approach detection mode the radar sensor is configured to cover a field-of-view with an azimuth angle of at least 100 degrees and an elevation angle of at least 60 degrees.

17. Motor vehicle ( 1 ) according to one of the preceding claims , characterized in that , that the motor vehicle (1) has exactly the radar sensor as the sole kick sensor for detecting a kick gesture performed behind the motor vehicle (1), and / or that the motor vehicle (1) has exactly the radar sensor as the sole kick sensor for detecting a kick gesture performed in front of the motor vehicle (1).

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