KR102030168B1 - A Method for Filtering Ground Data and An Apparatus thereof - Google Patents

Abstract

An apparatus for filtering ground data is disclosed. The apparatus includes a sensor for receiving data about an object around a vehicle; A storage unit for storing the received data and predefined criteria; And a processor configured to compare the received data with the predefined criteria and to filter data about the object determined to represent the ground among the objects around the vehicle.

Description

A method for filtering ground data and an apparatus

The present invention relates to a technique for analyzing information measured using a laser emitted from a sensor of a vehicle to filter ground data and determine data on obstacles.

In general, data measured using a sensor such as LiDAR includes information on all objects detected within a measurement range. However, depending on the purpose of the system, data for some of the sensed data may become noise data and may be unnecessary. For example, in the case of a vehicle system that wants to recognize a surrounding object, a surrounding vehicle, a person, and the like, data that is detected and displayed on the ground is unnecessary and should be removed. In the case of a multi-layer LiDAR, the lower layer often faces the ground, and even if the lower layer faces the ground due to rolling or pitching of the vehicle.

It is an object of the present invention to provide a method and apparatus for efficiently filtering ground data from measured data using a sensor.

However, it is not intended to limit the contents disclosed herein for the above purpose, all the specific details for carrying out the invention or the intention mentioned in the claims are included for the purpose of the present invention.

An apparatus for filtering ground data for solving the above problems includes a sensor for receiving data on an object around a vehicle; A storage unit for storing the received data and predefined criteria; And a processor configured to compare the received data with the predefined criteria and to filter data about the object determined to represent the ground among the objects around the vehicle.

The sensor may emit one or more beams to detect the object, and each of the beams may include a plurality of different layers.

In addition, the processor may acquire a slope from data about objects detected in two adjacent layers among the layers, and determine that the detected object represents the ground when the slope corresponds to the predefined criterion. Can be.

The processor may be further configured to obtain a distance between the sensor and the detected object from data about objects detected in two adjacent layers among the layers, and the difference value of the obtained distance corresponds to the predefined criterion. In this case, it may be determined that the detected object represents the ground.

The predefined criterion may be an EPW value representing a road, and the processor may indicate that the object represents the ground when an echo pulse width (EPW) value included in the received data corresponds to the predefined criterion. You can judge.

The predefined criterion may include a reference EPW value indicating a reference angle, a reference distance difference, and a road, and the processing unit may include an inclination from data for objects detected in two adjacent layers among the layers, and each object. Comparing the distance difference with respect to and the EPW value included in the received data with the reference angle, the reference distance difference, and the reference EPW value, respectively, and in all cases if it is determined that the object represents the ground. You can filter the data.

In addition, the method for filtering the ground data by the vehicle system for solving the above problems, the method comprising the steps of: receiving data on an object around the vehicle using a sensor; Storing the received data in a storage unit; Comparing the received data with predefined criteria; And filtering the data determined to represent the ground of the object based on the comparison result.

According to the present invention, when sensing the data around the vehicle by using a sensing unit such as a lidar sensor, it is possible to effectively filter the data corresponding to the ground to provide a user with a processing result that guarantees accuracy and reliability. have.

1 illustrates a general situation of detecting a vehicle surroundings using a sensor.
2 shows an exemplary image of processing information about an object in front of a vehicle.
3 illustrates a method of identifying data, which is determined to be the ground, among the data sensed by the sensor.
4 shows an example of a ground data filtering apparatus according to the present invention.
5A and 5B show examples of a ground data filtering system according to the present invention.
6 shows a flowchart of a method of processing ground data according to the present invention.

Hereinafter, various embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In this case, it should be noted that like elements are denoted by like reference numerals as much as possible. In addition, detailed descriptions of well-known functions and configurations that may blur the gist of the present invention will be omitted. That is, in the following description, only parts necessary for understanding the operation according to the embodiment of the present invention will be described, and it should be noted that the description of other parts will be omitted so as not to distract from the gist of the present invention.

In the following description, the electronic device of the present invention, like all information communication devices, multimedia devices, and application devices that support the functions described in various embodiments of the present invention, includes an application processor (AP), a graphics processing unit (GPU), It can include any device that uses a central processing unit (CPU). For example, the electronic device includes a mobile communication terminal operating based on communication protocols corresponding to various communication systems, a tablet personal computer, a smart phone, Digital cameras, portable multimedia players (PMPs), telematics, navigation devices, and other in-vehicle systems.

In this specification, an object means an object sensed by a sensor. For example, the sensor may emit one or more beams to collect information about the object from the reflected beam, where the subject reflecting the beam may be understood as an object herein. Objects such as ground, roads, side walls, and obstacles may correspond to objects.

1 illustrates a general situation of detecting a vehicle surroundings using a sensor. The vehicle 100 may include a sensor 110 for collecting information, such as an obstacle in front of the front. The sensor 110 may emit a beam such as a laser to collect information about an object around the vehicle 100 from the reflected data. Referring to FIG. 1, the vehicle 100 is driving on a road 130 having an uneven road, and an obstacle 120 such as a pedestrian is positioned in front of the vehicle 100. Some of the beams emitted from the sensor detect the road 130, and others detect the obstacle 120. The beam radiated from the sensor 110 may be radiated at a plurality of angles with respect to the ground. That is, the beam emitted from the sensor 110 may have a plurality of layers in a direction perpendicular to the ground. At this time, even if the lowermost layer is parallel to the ground or indicates upward direction, if the road meets a certain uphill road or the road surface is uneven, the data on the ground is also lower. Can be collected.

The data collected through the sensor 110 may be processed and displayed to a user (eg, a vehicle driver). An exemplary image in this regard is shown in FIG. 2.

2 shows an exemplary image of processing information about an object in front of a vehicle. The first image 210 represents an image of the front of the vehicle photographed by the camera. The second image 220 is a processed image generated based on the data collected from the sensor. Although not shown, the second processed image may be provided through a display unit, such as a telematics, a head unit display (HUD), or a smart device, which filters ground data in the second image 220 and is user-friendly. .

Referring to the first image 210, there are no obstacles in front of the vehicle in operation. However, in addition to data determined to be collected from walls on both sides of the road, the second image 220 processed based on the data sensed by the sensor may actually be data that detects the drawing, but may be judged as if it is a specific obstacle in front. Data that can be included. In other words, the road surface in front of the second image 220 is measured to appear as if there is an obstacle. The image finally provided to the user is required to filter such data. Hereinafter, referring to FIG. 3, a method of identifying data determined to be the ground will be described.

3 illustrates a method of identifying data, which is determined to be the ground, among the data sensed by the sensor. In FIG. 3, the sensor is shown to mean a lidar sensor, but any kind of sensor to which the method disclosed herein is applicable, for example, a radar or an ultrasonic sensor, may be understood as the sensor shown in FIG. 3.

In FIG. 3, the direction in which the vehicle travels may be understood as the y axis, the left-right direction of the vehicle travel direction as the x axis, and the direction perpendicular to the ground may be understood as the z axis. For example, if the lidar sensor can detect a field of vies (FOV) in front of the vehicle and the resolution is 0.1 °, the FOV of the lidar sensor consists of 1,000 beams. . In addition, when the lidar sensor supports four layers, each beam may consist of four layers. When the lidar sensor detects the front of the vehicle, 1,000 data for each layer and a total of 4,000 data can be sensed. Of course, this is exemplary, and the FOV, resolution, and number of layers supported by the lidar sensor may be adjusted differently according to a specific embodiment. In one example, the vehicle may have a plurality of lidar sensors, and the FOV may change due to the rotatable features of the sensors. However, even in a series of modified examples, the principle described below still applies to the method of filtering the data corresponding to the ground from the data sensed by the sensor. The following description will be based on a Lidar sensor that supports 100 ° FOV, 0.1 ° resolution, and four layers.

The left image of FIG. 3 shows object detection for the same layer, based on the traveling direction (y-axis) of the vehicle. In this example, the vehicle-mounted lidar sensor collects information about the detected object using 1000 beams in the forward reference 100 ° range. If the illustrated layer is the first (lowest) layer, each beam may be divided into seven beams (1, 1), beam (1, 2), or beam (1, 1000). If the second layer, it may be divided into beam (2, 1), beam (2, 2), or beam (2, 1000). That is, the beam radiated from the lidar sensor may be classified into a beam (layer, n). The collected information may include a distance from the sensor to the object, whether the object is moved, and an echo pulse width (EPW) of the received reflection signal.

3 shows the detection of an object for beams of the same order, based on the traveling direction (y-axis) of the vehicle. For convenience, it can be understood as data for the 100th beam from the left side (the driver side with respect to the center of the vehicle). That is, the beam shown in the right image of FIG. 3 may be understood as beam (1,100), beam (2,100), beam (3,100), and beam (4,100).

Objects around the vehicle are detected by the beam emitted from the lidar sensor. By the 100th beam, four sensed data are obtained, one for each layer (ie, the first layer to the fourth layer). Values obtained by the aforementioned beams may be defined as value (1,100), value (2,100), value (3,100), and value (4,100). Hereinafter, for convenience, the four beams shown will be described as B1, B2, B3, and B4, and the sensed four values will be described as V1, V2, V3, and V4.

(1) slope condition

In the case where V1 and V2 are data sensed by the ground and V3 and V4 are data detected by obstacles, the virtual line connecting V1 and V1 is relatively compared to the virtual line connecting V3 and V4. The angle (tilt) to the ground becomes small. (Ie, θ1 < θ2) Further, in general, the angle with the measurement direction of the lidar sensor (the traveling direction of the vehicle) is close to zero in the case of the ground and close to 90 degrees in the case of an obstacle.

The slope of this imaginary line can be obtained using a simple trigonometric function. In general, the radiation angle of the beam constituting the layer of the lidar sensor is fixed. For example, when the radiation angle of the first layer is α with respect to the z axis, the radiation angle of the second layer is β with respect to the z axis, and the first layer is a lower axis than the second layer, θ1 is expressed as follows. Can be determined.

Here, r1 means the distance from the sensor to the V1 detection point, r2 means the distance from the sensor to the V2 detection point. The slope is not always determined by the above equation, but may be obtained based on appropriate approximation and correction.

A predetermined reference value for determining whether the sensed data corresponds to the ground may be set. This reference value is based on information such as the height at which the lidar sensor is located, the angle at which the beam is emitted (with respect to the z axis) in each layer of the lidar sensor, and the angle at which the beam is emitted (with respect to the y axis) in the same layer. Can be set. If the measured slope indicates an angle smaller than this reference value, it may be determined as a road surface, and if the measured slope is greater than this reference value, it may be determined as an obstacle. Such a reference value may be determined experimentally or set by a user.

A predetermined reference range for determining whether the sensed data corresponds to the ground may be set. For example, when the inclination is less than 20 degrees, it may be determined as a road, if the slope is less than or equal to 20 degrees and less than 60 degrees, the judgment is suspended, and when it is more than 60 degrees, it may be determined as an obstacle. In the illustrated example, the slope measured by the first layer and the second layer is included in the range of the road, but the slope measured by the second layer and the third layer may be included in the determination hold range. In this case, when the slopes measured by the third layer and the fourth layer are included in the obstacle range, the data measured by the third layer may be finally determined as an obstacle. Alternatively, the characteristics of the data sensed by the third layer may be finally determined by the density condition or the EPW condition described later.

(2) density conditions

Even if the aforementioned slope is relatively large, it may correspond to a road. For example, when there is a low jaw in front of the vehicle or when a high hill length is located in front of the vehicle, the inclination of the imaginary line connecting the measured values in the two layers may be largely measured. Alternatively, a situation in which it is difficult to reliably determine whether the measured data is a road may occur due to the inclination condition. In order to compensate for this, the density of the measured values may be used.

Generally, the road is flat and exists in a wide range so that even if there is a curvature, the operation of the vehicle does not interfere. In contrast, obstacles such as pedestrians, other vehicles, and roadside trees are often disposed vertically on the road. Therefore, as described above, when the beams included in the first layer and the second layer face the road surface, and the beams included in the third layer and the fourth layer face the obstacle, the beams measured in the first layer are measured from the sensor. The distance r1 to the object (road) and the distance r2 to the object (road) measured in the second layer are relatively long due to the characteristics of the road. That is, the distribution of distance values is distributed. However, the distance r3 to the object (obstacle) measured in the third layer and the distance r4 to the object (obstacle) measured in the fourth layer have almost similar values. In other words, the distribution of distance values appears concentrated at a certain numerical value. Therefore, when the distances detected by the sensors in different layers are concentrated within a specific reference value, the corresponding data may be determined as the data detected as an obstacle. For example, if the distance value measured by the beam (3,800) to beam (3, 900) and the beam (4,800) to the beam (4,900) is detected within a specific reference value (for example, within 50 cm), It may be determined that there is a predetermined obstacle on the right side of the traveling direction.

(3) EPW conditions

The received pulse width may be used to determine whether the sensed data represents ground or an obstacle. In general, in the case of the ground, the angle of incidence of the beam is large, especially in the case of road, the color of the asphalt is often black. Therefore, in general, the EPW value of the beam reflected from the object corresponding to the ground is larger than the EPW value of the beam reflected from the obstacle.

Each beam is composed of a plurality of layers as shown in FIG. 3, and a slope may be obtained from data about an object detected in an adjacent layer. For example, both V1 acquired in the first layer and V2 acquired in the second layer are data about the ground, and a slope of the ground may be obtained therefrom. In addition, V2 and V3 are data obtained from the ground and obstacles, respectively. The slope obtained from this may have a suitable value between the slope of the conventional ground and the slope of the conventional obstacle. In addition, both V3 and V4 are data obtained from the obstacle, from which the slope of the obstacle may be obtained. As described above, a slope between objects detected in two adjacent layers may be obtained by sequentially comparing the first layer to the fourth layer, or the lower layer to the upper layer.

 In a similar manner, the distance difference between objects measured in adjacent layers can be obtained. The distance between the object corresponding to V1, V2, V3, V4 and the sensor may be obtained as r1, r2, r3, r4, and the distance difference value between r1 and r2, r2 and r3, r3 and r4 may be obtained. have. In the illustrated example, a distance difference value between r1 and r2, r2 and r3 has a relatively large value, but a distance difference value between r3 and r4 corresponding to an obstacle has a relatively small value. In other words, the distribution of distance values is densely displayed.

When at least one of the above-described tilt condition, density condition, and EPW condition is satisfied, the object may be determined as data acquired from the ground. However, in an embodiment, in order to improve the accuracy of the filtering result, an object satisfying all three conditions may be determined to represent the ground.

Hereinafter, a ground data filtering apparatus according to an embodiment of the present invention will be described with reference to FIGS. 4 to 5.

4 shows an example of a ground data filtering apparatus according to the present invention. Referring to FIG. 4, the ground data filtering device 400 includes a sensing unit 410, a storage unit 420, a processing unit 430, and a display unit ( 440). In addition, the storage unit 420 may include a data matrix 422, an EPW value 424, and information on other predefined reference values.

The sensing unit 410 may be a kind of sensor. For example, a lidar sensor, a radar sensor, an ultrasonic sensor, and the like may correspond to the sensing unit 410. The detector 410 receives data about an object located near the vehicle. In addition, the sensing unit 410 may include two or more sensors, and the position at which the sensor is attached to the vehicle may be fixed, flexible, or adjusted by a user.

The range detected by the detector 410 may correspond to the entire orientation of the vehicle according to the attachment position of the sensor. In the present invention, it can typically be understood as a predetermined range in front of the vehicle. The predetermined range is determined by the characteristics of the sensor. For example, when the FOV of the sensor is 100 °, the predetermined range is a linear distance supported by the beam characteristic of the sensor within a range of 50 ° to the left and the right of the traveling direction from the point where the sensor is located on the vehicle, that is, the fan shape. It can be an area of form. For example, when the beam of the sensor can measure up to a linear distance L, and the FOV is α, the predetermined range is 0.5 * α * L ² . In addition, the sensor may detect an object from a region that spans a plurality of layers corresponding to the predetermined range, according to a supporting layer.

The storage unit 420 stores data about the object collected by the sensor. This storage may be an HDD, SSD, SD card, or flash memory. The data may be stored in a kind of data matrix 422. The data matrix 422 may be composed of a layer row and a beam column. For example, the first row includes data about objects collected in the first layer, and the second row includes data about objects collected in the second layer. Such a data matrix sequentially compares data corresponding to corresponding layer rows in the same beam column (for example, comparing values of first layer, second layer, ..., nth layer for the first beam). It can be used to determine whether the object is an object representing the ground.

The storage unit 420 may also store the EPW values 424. In addition, the storage unit 420 may store pre-stored EPW values indicating roads. These EPW values 242 may be used to determine whether the data received from the object is a road or not. In addition, the storage unit 420 may include information about a reference angle value, a reference distance difference value, or a range thereof used to determine whether the object represents the ground. Other data (426)

The processor 430 may determine whether an object represents the ground using data stored in the storage 420. For example, the processor 430 may determine, from the data about the objects sensed in two adjacent layers (ie, two adjacent rows) in the data matrix, an angle, that is, an inclination, of the virtual solid line connecting the two objects with the ground. Can be obtained. This obtained slope is compared with a predefined criterion. If the obtained inclination is smaller than the predetermined angle or included in the range of the angle defined as representing the ground, that is, when the inclination condition is satisfied, the object may be determined to represent the ground.

In addition, the processor 430 may obtain a distance between the sensor and the object from data about the objects sensed in two adjacent layers. If the difference between the distance values between the two objects and the sensor is less than or equal to a predetermined size, or is included in the range of the size defined as representing the ground, that is, if the density condition is satisfied, the object may be determined to represent the ground. have.

In addition, when the EPW value included in the received data is an EPW value corresponding to a road, the processor 430 may determine that the object represents the ground.

Although data about an object that satisfies at least one of the above criteria may be determined as ground data, data about an object that satisfies all of the above criteria may be determined as ground data in order to improve accuracy.

The display unit 440 provides a result of filtering the ground data to the user or the vehicle driver. In this case, the provided image may be a user-friendly image that is properly processed. For example, if the ground data indicates that the filtered detection result indicates that there is an obstacle within a certain forward distance, the steering guide of the steering wheel may be provided together with the guide for the corresponding position or distance.

Such a display or other part of the device 400 may be implemented as a separate stand-alone device, an example of which will be described with reference to FIGS. 5A and 5B.

5A and 5B show examples of a ground data filtering system according to the present invention. In describing the configurations shown in FIGS. 5A and 5B, descriptions overlapping with the aforementioned configurations will be omitted.

Referring to FIG. 5A, the system includes a processing device 510 and a display device 520. The processing device 520 includes the aforementioned sensing unit 410, the storage unit 420, and the processing unit 430, and further includes a communication unit 450. The communicator 450 may be connected to the communicator 524 included in the display apparatus 520 to provide data such that the result of filtering the ground data by the display unit 522 of the display apparatus 520 is displayed. The connection between the communicator 450 and the communicator 524 may be performed through a short distance communication such as Wi-Fi, Bluetooth, or NFC, as well as a wired connection such as a LAN. For example, the processing device 510 may be a telematics system mounted on a vehicle, and the display device 520 may be a mobile computing device such as a smart phone, tablet, or smart watch capable of communicating with telematics. In addition, the display device 520 may be a HUD of a vehicle.

5B shows another configuration example of the system. Referring to FIG. 5B, the sensing unit 410 is configured independently of the processing apparatus 530. The sensing unit 410 and the processing unit 530 may be connected by a can bus or the like. By configuring the sensing unit 410 separately from the processing unit 530, replacement, exchange, addition, etc. of the sensing unit 410 may be facilitated.

6 shows a flowchart of a method of processing ground data according to the present invention. The process begins at step 610. In operation 620, the system collects data about an object located around the vehicle using a sensor or the like. The sensor emits one or more beams to sense the object, and the beam has a plurality of layers. In step 630 the system stores the data received by the sensor in the storage. The data to be stored may have the form of a data matrix. Since the description of the data matrix has been described above, it will be omitted. In addition, EPW values included in the received data may be stored. Steps 642, 644, and 646 compare the received data, or data obtained therefrom, with a criterion predefined in the system. Steps 642, 644, and 646 may be performed sequentially or simultaneously.

In step 642, the slope for the two objects detected in the adjacent layers is determined. The inclination may refer to an angle between a virtual solid line connecting two objects and the ground.

In operation 644, the density of two objects detected in an adjacent layer is determined. The density is determined from the difference between the distance values between the two objects and the sensor. The smaller the difference in the distance value is, the higher the density is, and the larger, the lower the density is.

In step 646, the EPW value included in the collected data is determined.

In step 650, it is determined whether the slope, density, and EPW determined in steps 642, 644, and 646 meet a predefined criterion (condition). If the condition is satisfied, the object may be determined to represent the ground (step 662). If not, the object may be determined to be an obstacle (step 664). According to an embodiment, when at least one of the slope, density, and EPW condition is satisfied, it may be determined as the ground. In another embodiment, when all three conditions are satisfied, the object may be determined as the ground. Ground data can be filtered.

In step 670 the process ends. However, as described above with reference to FIG. 5, the filtered result of the ground data may be displayed or transmitted to another device for display. In addition, the data acquired in step 620 may be transferred between devices before being stored in a predetermined storage unit in step 630. That is, the flowchart shown in FIG. 6 is exemplary and some steps corresponding to the above description at the level of those skilled in the art may be omitted or added.

In the present specification, an element represented as a means for performing a specific function encompasses any way of performing a specific function, and the element may be a combination of circuit elements performing a specific function, or software for performing a specific function. It may include any form of software, including firmware, microcode, and the like, coupled with suitable circuitry to perform.

Reference herein to 'one embodiment' of the principles of the present invention and various modifications of this expression are intended to include that particular features, structures, characteristics, and the like, are included in at least one embodiment of the principles of the invention in connection with this embodiment. it means. Thus, the expression 'in one embodiment' and any other modifications disclosed throughout the specification are not necessarily all referring to the same embodiment.

All embodiments and conditional examples disclosed through the specification are intended to help those skilled in the art to understand the principles and concepts of the present invention, and those skilled in the art to which the present invention It will be understood that modifications may be made without departing from the essential features of the invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

400: ground data filtering device
410: detector
420: storage
430: processing unit
440: display unit

Claims (12)

An apparatus for filtering ground data,
A sensor that receives beams of different layers to receive data about objects around the vehicle;
A storage unit which stores data about the received object and predefined criteria; And
And a processor configured to filter data about the object determined to represent the ground among the objects around the vehicle by comparing angles formed by a straight line connecting the sensed objects on the layers adjacent to each other with the predefined criteria. Device.
delete delete delete An apparatus for filtering ground data,
A sensor that receives beams of different layers to receive data about objects around the vehicle;
A storage unit which stores data about the received object and predefined criteria; And
A processing unit for filtering data for the object determined to represent the ground among the objects around the vehicle by comparing an echo pulse width (EPW) value included in the data for the received object with the predefined criterion; Device.
An apparatus for filtering ground data,
A sensor that receives beams of different layers to receive data about objects around the vehicle;
A storage unit which stores data about the received object and predefined criteria; And
The angle between the straight line and the ground connecting the detected objects in the adjacent layers, the distance difference between the detected objects in the adjacent layers, and the Echo Pulse Width (EPW) value included in the data about the received object. And a processing unit for filtering data for the object, which is determined to represent the ground among the objects around the vehicle, in comparison with a predefined criterion.
A method for a vehicle system to filter ground data,
Radiating beams of different layers to receive data about objects around the vehicle;
Storing data for the received object and predefined criteria;
Comparing angles formed by a straight line connecting the sensed objects in adjacent layers with each other and the ground, respectively, to the predefined reference; And
And based on the comparison result, filtering the data determined to represent the ground of the object.
delete delete delete A method for a vehicle system to filter ground data,
Radiating beams of different layers to receive data about objects around the vehicle;
Storing data for the received object and predefined criteria;
Comparing an echo pulse width (EPW) value included in data for the received object with the predefined criterion; And
And based on the comparison result, filtering the data determined to represent the ground of the object.
A method for a vehicle system to filter ground data,
Radiating beams of different layers to receive data about objects around the vehicle;
Storing data for the received object and predefined criteria;
The angle between the straight line and the ground connecting the detected objects in the adjacent layers, the distance difference between the detected objects in the adjacent layers, and the Echo Pulse Width (EPW) value included in the data about the received object. Comparing each with a predefined criterion; And
And based on the comparison result, filtering the data determined to represent the ground of the object.

Images