Method for detecting environmentally induced sensor impairment and vehicle sensor system

Abstract

The invention relates to a method for detecting (10) an environmental impairment of a radar sensor (12) of a vehicle (14), comprising the steps of providing (18) an environmental sensor system (22) comprising the radar sensor (12) and at least one further environmental sensor (20) for detecting at least one environmental object (24) in a vehicle environment (26) of the vehicle (14), detecting (34) an environmental area (32) of the vehicle environment (26) by the radar sensor (12) and at least the further environmental sensor (20), which at least partially contains the environmental object (24) and lies in a field of view (V1) of the radar sensor (12) and a field of view (V2) of the at least further environmental sensor (20), and creating (38) an environmental object model (40) of the environmental object (24) depending on the detection (34) of the environmental area (32) by the radar sensor (12) and at least the further environmental sensor (20). (20) formed fused sensor data (42),Determining (58) a contribution (60) of the radar sensor (12) to the fused sensor data (42), calculating (76) an impairment state (78) of the radar sensor (12) depending on the contribution (60). The invention further relates to a vehicle sensor system (17).

Description

[0001] The invention relates to a method for detecting an environmentally induced sensor impairment of a radar sensor according to claim 1. Furthermore, the invention relates to a vehicle sensor system. State of the art

[0002] EP 4 407 339 A1 describes a method for detecting environmental sensor impairment in a radar sensor, in which raw sensor data from the radar sensor and object detection results obtained from it are evaluated, and an impairment state of the radar sensor is calculated solely based on the raw sensor data and the object detection results. Disclosure of the invention

[0003] According to the present invention, a detection method with the features of claim 1 is proposed. This allows the sensor impairment of the radar sensor to be detected more reliably and accurately.

[0004] The additional environmental sensor can be a radar sensor, a lidar sensor, an ultrasonic sensor, or a camera.

[0005] The radar sensor and / or the additional environmental sensor can be located in the front, corner, side, roof, or rear of the vehicle. The radar sensor and / or the additional environmental sensor can detect the vehicle's surroundings in front of, beside, and / or behind the vehicle.

[0006] The environmental sensor system is located inside the vehicle.

[0007] The surrounding object can be a building, a facility, a device, an object, another vehicle, a living being, or a plant.

[0008] Environmental sensor interference can be caused by obstruction of vision, particularly by precipitation such as rain, and / or by occlusion, especially by contamination, wetting, and / or coating with unwanted material on a sensor surface of the radar sensor. This material can include water, ice, snow, dirt, dust, sand, and / or organic matter. Environmental sensor interference can only result from environmental influences affecting the radar sensor.

[0009] Sensor impairment can result in a reduction in the radar sensor's detection performance with regard to the detection of objects in the vehicle's surroundings. This reduction in detection performance can include a decrease in the radar sensor's resolution, range, accuracy, field of view, and / or sensitivity.

[0010] The surrounding area can be defined by an elevation angle, an azimuth angle range, and a distance.

[0011] The radar sensor data can be processed from the radar sensor's measurement data. The radar sensor's measurement data can form the basis of the radar sensor's own sensor data. The sensor data of the other environmental sensor can be processed from the measurement data of the other environmental sensor. The measurement data of the other environmental sensor can form the basis of the other environmental sensor's own sensor data.

[0012] The environment object model can specify at least one parameter for the environment object. This parameter can be a position, size, elevation angle, azimuth angle, distance, velocity, direction of movement, planned trajectory, or classification of the environment object.

[0013] Creating the environment object model based on sensor data can involve selecting the underlying environment object from several environment objects that lie at least partially within the environment, and / or selecting one environment object model from several environment object models, each of which is calculated to represent environment objects that lie at least partially within the environment. The selection can be based on the distance of the environment object from the environmental sensor system. The selected environment object can be the one closest to the environmental sensor system within the environment.

[0014] The surrounding area can lie within an overlap of the radar sensor's field of view and the field of view of the other environmental sensor. The surrounding area can encompass the entire overlapping area or a portion thereof.

[0015] The contribution of the radar sensor to the fused sensor data can be measured based on a redundancy of information that can be confirmed by the acquisition of at least one other environmental sensor, a consistency of information between the radar sensor and the at least one other environmental sensor, a reliability of the information from the radar sensor and / or an accuracy of the information from the radar sensor.

[0016] In a preferred embodiment of the invention, it is advantageous if determining the contribution includes determining at least one contribution value. The contribution value can be binary or multi-valued. If the contribution value is binary, a contribution of the radar sensor to the fused sensor data can be represented by 1, and no contribution or a contribution below a threshold by 0. If the contribution value is multi-valued, a gradation of the contribution can be made depending on the contribution of the radar sensor to the fused sensor data. Here, 0 can represent no contribution and 1 the maximum possible contribution, and the values ​​in between can be calculated depending on a contribution percentage.

[0017] In a preferred embodiment of the invention, it is advantageous if determining the contribution includes storing the determined contribution value in a value memory. The value memory can be a list or an array. Storing the contribution value in the value memory can involve appending the currently determined contribution value to the list or adding an entry to the array.

[0018] Determining the contribution of the radar sensor to the fused sensor data can depend on at least one entry condition.

[0019] In a specific embodiment of the invention, it is advantageous if the storage of the contribution value in the value memory depends on at least one entry condition. This allows for pre-filtering before storage.

[0020] In a preferred embodiment of the invention, it is advantageous if the entry condition comprises at least one of the following entry criteria: the vehicle's speed is above a limit value, the vehicle's yaw rate is below a limit value, the number of environmental objects in the surrounding area is above a lower limit value and below an upper limit value, or the position of the detected environmental object is within a predetermined spatial validity area of ​​the surrounding area. These limit values ​​are predetermined. They can change during vehicle operation, for example, depending on environmental and / or driving conditions.

[0021] The entry condition can include at least two of the specified entry criteria. The spatial scope can be defined by a minimum and maximum longitudinal and / or lateral distance between the environmental sensor system and the surrounding object. The longitudinal distance can be along a longitudinal axis, and the lateral distance can be along a transverse axis of the vehicle. The yaw rate can indicate a rotational movement of the vehicle about a vertical axis.

[0022] The entry condition can be met if one, several or all of the entry criteria are fulfilled.

[0023] In a specific embodiment of the invention, it is advantageous if the method for acquiring and storing the determined contribution value by appending it to the value memory is executed repeatedly, and the sensor impairment state is calculated based on the contribution values ​​in the value memory. The repeated execution can be timed by measurement cycles of the radar sensor. The method can be executed at most once per measurement cycle of the radar sensor. The method can be executed for two consecutive measurement cycles.

[0024] The value storage can be a ring buffer. Storing the determined contribution value in a filled value storage can be done by removing the oldest stored determined contribution value.

[0025] In an advantageous embodiment of the invention, at least one result contribution value is calculated from the contribution values ​​in the value memory. The result contribution value can be calculated as the mean of the contribution values ​​in the value memory. The mean can be an arithmetic, geometric, or quadratic mean. The mean can be an average value, calculated, for example, based on the following relationship. E=AS with the result contribution value E, the number A of 1 in the value storage for binary contribution value and the number of possible entries (size) S of the value storage.

[0026] In a preferred embodiment of the invention, it is advantageous to apply a filter to the result contribution value and to calculate the sensor impairment state as a function of the filtered result contribution value. The filter can be an Infinite Impulse Response (IIR) filter.

[0027] Alternatively or additionally, the filter can be applied to the contribution value and / or a sequence of contribution values ​​when the procedure is executed repeatedly.

[0028] In a preferred embodiment of the invention, it is advantageous if the sensor impairment state comprises a sensor impairment degree, and the calculation of the sensor impairment state includes a calculation of the sensor impairment degree of the radar sensor. The sensor impairment degree can be binary or multiple. If the sensor impairment degree is binary, 1 can represent impairment and 0 can represent no impairment.

[0029] The smaller, less frequent and / or more irregular the contribution of the radar sensor to the fused sensor data, the more likely it is that the radar sensor is impaired, and therefore the more likely it is that a binary sensor impairment level will be 1 and the more likely it is that a multi-valued sensor impairment level will be greater.

[0030] The sensor impairment level can quantitatively describe the sensor impairment, in particular the reduction in detection performance. For example, a sensor impairment level with a value of 1 from a range of 0 to 1 can indicate a complete impairment of the radar sensor, in particular a complete lack of detection performance from the radar sensor.

[0031] Depending on the detected degree of sensor impairment, measures can be taken, such as issuing a warning message, signaling to a user of the vehicle, assessing the reliability of the creation of the environmental object model, and / or cleaning the radar sensor to remove and / or reduce the impairment.

[0032] According to the present invention, a vehicle sensor system with the features of claim 10 is further proposed. The processing device can be associated with a control unit of the vehicle. The processing device can be arranged in the vehicle. The processing device can comprise at least one processor for performing at least one of the steps or partial steps of the detection method.

[0033] Further advantages and advantageous embodiments of the invention will become apparent from the description of the figures and the illustration. Character description

[0034] The invention is described in detail below with reference to the illustration. The figure shows a method for detection and an environmental sensor system, each in a specific embodiment of the invention. The method for detecting 10 an environmentally induced sensor impairment of a radar sensor 12 of a vehicle 14 can be carried out by a processing device 16 of a vehicle sensor system 17 in the vehicle 14 and initially comprises providing 18 an environmental sensor system 22 comprising the radar sensor 12 and at least one further environmental sensor 20 for detecting at least one environmental object 24 in a vehicle environment 26 of the vehicle 14. The radar sensor 12 and the further environmental sensor 20, for example a camera 28, can be arranged on a vehicle front 30 of the vehicle 14 and detect a front environmental area 32 of the vehicle 14. The fields of view V of the radar sensor 12 and the further environmental sensor 20 overlap at least partially.

[0035] Furthermore, the radar sensor 12 and at least the additional environmental sensor 20 detect 34 an area 32 of the vehicle's surroundings 26 which at least partially contains the surrounding object 24 and lies within a field of view V1 of the radar sensor 12 and a field of view V2 of the additional environmental sensor 20. The surrounding object 24 is therefore located at least partially within an overlap area 36 of the field of view V1 of the radar sensor 12 and the field of view V2 of the additional environmental sensor 20. The surrounding area 32 can encompass the entire overlap area 36 or a portion thereof. The detection 34 of the surrounding object 24 is carried out using sensor data 37 provided by the radar sensor 12 and the additional environmental sensor 20.

[0036] Furthermore, an environment object model 40 of the environment object 24 is created based on the fused sensor data 42 generated by the radar sensor 12 and at least one other environment sensor 20, which is acquired through the acquisition of the environment area 32 (i.e., the sensor data). The environment object model 40 can be calculated using sensor fusion and the resulting fused sensor data 42. The environment object 24 for which the environment object model 40 is created can be selected from several environment objects 24 that lie at least partially within the environment area 32. For example, the selected environment object 24 could be the one closest to the vehicle 14.It is also possible to create an environment object model 40 for each environment object 24 of the multiple environment objects 24, and to subsequently use the environment object model 40 of a selected environment object 24, while excluding the other environment object models 40 from subsequent use.

[0037] The selection or creation of the environment object model 40 may be preceded by a check 44 of an entry condition 46. The entry condition 46 may comprise several entry criteria 48. The entry criteria 48 may be as follows: The vehicle 14's speed 50 is above a limit value, the vehicle 14's yaw rate 52 is below a limit value, the number of environment objects 24 in the environment 32 is above a lower limit value and below an upper limit value, and the position 56 of the detected environment object 24 is within a predefined spatial validity area of ​​the environment 32. The spatial validity area may be defined by a minimum and maximum longitudinal and / or lateral distance between the environment sensor system 22 and the environment object 24.

[0038] If the verified entry condition 46 is met, for example by fulfilling some or all of the entry criteria 48, the previously described selection of the environment object model 40 calculated depending on the fused sensor data 42 or of the environment object 24 for which the environment object model 40 is calculated depending on the fused sensor data 42 is carried out.

[0039] Subsequently, a contribution 60 from radar sensor 12 to the fused sensor data 42 is determined. Determining the contribution 60 can include determining at least one contribution value 64 of the contribution 60. The contribution value 64 can, for example, be binary. In this case, a contribution 60 from radar sensor 12 to the fused sensor data 42 is represented by 1, and no contribution 60 or a contribution 60 below a threshold is represented by 0. Determining the contribution 60 involves storing the determined contribution value 64, here 1 or 0, in a value memory 66, which is, for example, an array 68 of a predefined size. The contribution value 64 is specifically inserted into the array 68. The value memory 66 can be a ring buffer. Storing the determined contribution value 64 in a filled value memory 66 can be accomplished by removing the oldest stored determined contribution value 64.

[0040] The described procedure for recording 10, and thereby storing the determined contribution value 64 by appending it to the value memory 66, is preferably repeated and, for example, executed in a clocked manner according to the measurement cycles of the radar sensor. Thus, with an increasing number of repetitions of the procedure, the value memory 66 is filled with the contribution values ​​64.

[0041] Furthermore, a check 70 is performed to verify the complete occupancy of the value memory 66 based on the known number of possible entries in the value memory 66 and the recorded number of measurement cycles for which the procedure was executed. If the value memory 66 is full, a result contribution value 72 is calculated from the contribution values ​​64 in the value memory 66. The result contribution value 72 can be calculated as the average value of the contribution values ​​64 in the value memory 66.

[0042] Subsequently, a filter 74, for example an Infinite Impulse Response Filter 74, is applied to the result contribution value 72, thus calculating a filtered result contribution value 75.

[0043] Finally, a sensor impairment state 78 of the radar sensor 12 is calculated 76 depending on the contribution 60, in particular depending on the filtered result contribution value 75. The calculation 76 of the sensor impairment state 78 can include a calculation 76 of a sensor impairment degree 80 of the radar sensor 12. For example, the sensor impairment degree 80 is multi-valued and is higher the smaller the filtered result contribution value 75 is. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 4 407 339 A1

[0002]

Claims

[1] Method for detecting (10) an environmental sensor impairment of a radar sensor (12) of a vehicle (14), comprising the steps of providing (18) an environment sensor system (22) comprising the radar sensor (12) and at least one further environment sensor (20) for detecting at least one environment object (24) in a vehicle environment (26) of the vehicle (14), Detection (34) of an area (32) of the vehicle environment (26) which at least partially contains the surrounding object (24) and lies within a field of view (V1) of the radar sensor (12) and a field of view (V2) of the at least further surrounding sensor (20) by the radar sensor (12) and at least the further surrounding sensor (20), Creating (38) an environment object model (40) of the environment object (24) depending on the fused sensor data (42) formed by the detection (34) of the environment area (32) by the radar sensor (12) and at least the further environment sensor (20), Determining (58) a contribution (60) of the radar sensor (12) to the fused sensor data (42), Calculating (76) a sensor impairment state (78) of the radar sensor (12) depending on the contribution (60). [2] Method for detection (10) according to claim 1, characterized by , that determining (58) the contribution (60) includes determining (62) at least one contribution value (64) of the contribution (60). [3] Method for detection (10) according to claim 2, characterized by , that determining (58) the contribution (60) includes storing the determined contribution value (64) in a value storage (66). [4] Method for recording (10) according to claim 3, characterized by , that the storage of the contribution value (64) in the value storage (66) depends on at least one entry condition (46). [5] Method for recording (10) according to claim 4, characterized by , that the entry condition (46) includes at least one of the following entry criteria: a driving speed (50) of the vehicle (14) is above a limit value, a yaw rate (52) of the vehicle (14) is below a limit value, A number of the environment objects (54) in the environment area (32) are above a lower limit and below an upper limit, a location (56) of the recorded environmental object (24) is within a specified spatial validity area of ​​the environmental area (32). [6] Method for detection (10) according to any one of claims 3 to 5, characterized by , that the procedure for recording (10) and thereby storing the determined contribution value (64) by appending it to the value memory (66) is carried out repeatedly and the sensor impairment state (78) is calculated depending on the contribution values ​​(64) in the value memory (66). [7] Method for recording (10) according to claim 6, characterized by, that at least one result contribution value (72) is calculated from the contribution values ​​(64) in the value storage (66). [8] Method for detection (10) according to claim 7, characterized by , that a filter (74) is applied to the result contribution value (72) and the sensor impairment state (78) is calculated depending on the filtered result contribution value (75). [9] Method for recording (10) according to any one of the preceding claims, characterized by , that the sensor impairment state (78) includes a sensor impairment degree (80) and the calculation (76) of the sensor impairment state (78) includes a calculation (76) of the sensor impairment degree (80) of the radar sensor (12). [10] Vehicle sensor system (17) for a vehicle (14), comprising an environment sensor system (22) with a radar sensor (12) and at least one further environment sensor (20), each for detecting at least one environment object (24) in a vehicle environment (26) of the vehicle (14), a processing device (16) for creating an environment object model (40) of the environment object (24) depending on fused sensor data (42) formed by the detection by the radar sensor (12) and at least the further environment sensor (20) and for carrying out the detection method (10) according to one of the preceding claims.

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