EP4252197A2

EP4252197A2 - Evaluation of scanning information using position information

Info

Publication number: EP4252197A2
Application number: EP21823484.7A
Authority: EP
Inventors: Jan BEHLING; Mathias ROTGERI; Jan Sören EMMERICH; Dirk Höning; Patrick Klokowski; Christian Hammermeister; Michael Ten Hompel
Original assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Current assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Priority date: 2020-11-27
Filing date: 2021-11-23
Publication date: 2023-10-04
Also published as: CN116686015A; AU2021387768A1; AU2021387768B2; WO2022112221A3; WO2022112221A2; DE102020214974A1; US20230298208A1

Abstract

A description is given of an apparatus (100, 200) having a processing unit (110) that is designed to receive scanning information (120a) relating to a two-dimensional scan (120b) of a surface (130). The processing unit (110) is also designed to receive position information (120c) indicating an inclination of a capture unit (120, 510), which provides the two-dimensional scan (120b), with respect to the surface (130) and to evaluate the scanning information (120a) using the position information (120c) for locating the capture unit (120, 510) relative to the surface (130).

Description

Evaluation of scanning information using position information

description

technical field

The present invention relates to a device for evaluating scanning information using position information. The invention relates in particular to optical tilt compensation via rotary encoders.

Background of the Invention

Automated vehicles require some form of localization in order to be able to move safely through space, for example. Cameras or other optical sensors can be used here, with which previously mapped features in the environment can be found again by measurement, for example in the form of images. Since such measurements or observations can be incorrect, they are usually offset against the odometry of the vehicle using a statistical estimator, for example a Kalman filter. This process may require, for example, optical measurement of features whose only degree of freedom is the position of the vehicle. In the case of vehicles with suspension, the deflection of the chassis can change the distance between the vehicle and the ground. In addition, the entire vehicle can be inclined relative to a fixed reference point in the world if the deflection on the various wheels is different.

Vehicle deflection during operation can change in a number of ways. This can be caused by a change in the load status during operation, for example by picking up or delivering different heavy loads, a dynamic change in the acceleration vector, for example by hard braking or accelerating, a material defect, for example a defective spring-damper element, an uneven mass distribution in the vehicle and/or a change in the mass distribution in the vehicle, for example due to moving cargo. The deflection of the vehicle can change the position of the chassis and thus also the position of the sensor attached to the chassis in space, without changing the position of the vehicle on the ground level. It can therefore be a disruptive degree of freedom for localization. It should be noted that the deflection does not necessarily have to be caused by classic springs, but can also be caused by a certain softness in the chassis or running gear, for example by air-filled wheels.

State of the art

Two cases can be considered for previous solutions. On the one hand, a rigid chassis can be used, which is not unusual when vehicles are used indoors. The problem described above cannot or hardly arise here. For example, "faulty measurements" can only occur if, for example, the wheels of the vehicle lift off the ground during strong braking or acceleration processes. However, this can only happen for a very short period of time, for example, which is why the faulty measurement is of little or no consequence However, a rigid chassis can have the technical disadvantage that the vehicle cannot compensate for uneven ground.

On the other hand, i.e. in the case of sprung chassis, algorithms can be used when evaluating the measurements of the sensor, which are robust to the perspective distortion caused by the changed position of the sensor caused by the deflection. A good example of this can be localization via QR codes attached to the floor, such as those used by robots in warehouses, among other things. Such vehicles or robots can also be without springs, but QR codes are very robust in their recognition against perspective distortions. Other landmark-based localization methods, which are based on codes in the environment and not on the ground, for example, can work here in an identical or similar way.

However, marker-based approaches have the disadvantage that the markers, for example QR codes, have to be applied in the area beforehand and additional information about the location or the area around the marker has to be introduced into the marker. This, in turn, can entail additional costs and time. In addition, e.g. due to wearing out markers, For example, on floors that are driven on by vehicles, or if the markers are dirty, replacement or maintenance, eg repainting, may be necessary for the markers. This can also be accompanied by the further disadvantage of monitoring the condition of the markers in order to avoid accidents or breakdowns.

There is therefore a need for an improved concept that makes it possible to use vehicles that are sprung to ensure good driving characteristics and at the same time are not dependent on markers being applied in the area, which means, for example, that the navigation is independent, for example on the basis of optical scans, e.g. with the extraction of environmental features or inherent environmental features.

The object of the present invention is therefore to create an improved concept that makes it possible to use position information, which has information about a deflection of a spring-loaded vehicle, for example, and scanning information from a detection unit, which is part of the vehicle, for example, the detection unit and thus, for example, to localize the vehicle.

Summary of the Invention

The inventors have recognized that localization of a detection unit, which is part of a vehicle, for example, based on scanning information of a two-dimensional scan of a surface from the detection unit, with location information indicating an inclination of the detection unit with respect to the surface, and/or improved can be made possible. Embodiments according to the present invention are based on the core idea of using the position information to evaluate the scanning information with regard to the localization of the detection unit. The use of the location information enables simple pattern recognition and/or a quick calculation of the position.

According to one embodiment, a device includes a processing unit configured to obtain scanning information from a two-dimensional scan of a surface and to obtain position information indicating an inclination of a detection unit providing the two-dimensional scan with respect to the surface and to the scanning information to evaluate using the position information regarding a localization of the detection unit relative to the surface. The detection unit can be part of a vehicle that navigates over a surface. In order to localize the detection unit and thus the vehicle, for example, the processing unit of the device can receive scanning information from a two-dimensional scan of the surface from the detection unit. In the case of a sprung vehicle, the detection unit can have an inclination with respect to the surface, for example due to different deflection of individual wheels of the vehicle. In the case of a drone, the detection unit can have an inclination relative to the surface, for example due to a pitching or rolling movement.

It may not be possible or only with difficulty, for example, based on the scanning information alone, ie in particular without the additional use of markers, to evaluate the scanning information distorted, for example, by the inclination of the detection unit, with regard to the localization of the detection unit. Taking the inclination into account can have particular advantages in localization methods that are based on recognizing inherent features of the environment, for example features of the floor or the surrounding walls, instead of previously introduced markers. With such methods, for example, features in the form of patterns in the environment are recognized and compared with a database. Due to distorted scanning information, an assignment to features stored in the database, and thus localization, can fail. The processing unit is therefore designed to obtain the position information which indicates the inclination of the detection unit with respect to the surface. Thus, the inclination and thus, for example, a distortion can be taken into account in order to localize the detection unit.

According to one embodiment, a method includes obtaining scanning information of a two-dimensional scanning of a surface, obtaining position information indicating an inclination of a detection unit providing the two-dimensional scanning with respect to the surface, and evaluating the scanning information using the position information with regard to a localization of the detection unit relative to the surface.

Using a method according to the invention, the scanning information of the surface can be evaluated, taking into account the inclination of the detection unit, by considering the position information, with regard to a localization of the detection unit and/or an improved evaluation can be carried out. A method according to the invention can thus perform a localization based on scanning information which does not have any coded or other direct information about the inclination of the detection unit.

According to one embodiment, a computer program includes a program code for carrying out a method according to the invention. A computer program for carrying out the method according to the invention can be executed, for example, on a vehicle, such as a mobile robot platform, to localize the vehicle, and/or in a central processing unit, which, for example, receives scanning information from a large number of vehicles and on the basis of which the positions of the vehicles determined. In the form of a computer program, a method according to the invention can be used in a large number of applications and variants of applications, for example on microcontrollers or higher-performance computers of central processing units.

According to one exemplary embodiment, the processing unit is designed to manipulate the scanning information using the position information in order to obtain manipulated scanning information and to carry out an evaluation of the manipulated scanning information with regard to the localization of the detection unit relative to the surface.

By manipulating the scanning information using the position information, for example, a distortion of the scanning information due to an inclination of the detection unit with respect to the surface can be at least partially compensated. This can make it possible, for example, for subsequent evaluation methods, for example image evaluation methods, to be able to extract features from the scanning information, which enable localization of the detection unit. As a result, the detection unit can be localized more precisely and/or more robustly.

According to one embodiment, the processing unit is designed to rectify the scanning information based on the position information. Geometric distortions in scanning information, for example in the form of image data, can be at least partially corrected by rectification or equalization. Scanning information, for example an image, can thus be converted in such a way as if it had been recorded perpendicularly to the surface. As a result, distances and positions of features about which information is contained in the scanning information, and which contain information about the whereabouts of the detection unit on the surface, can be determined in order to compare this with a database, for example, in order to determine the position of the detection unit.

According to one embodiment, the detection unit has a camera and/or a laser distance sensor array. The use of a camera and/or a laser distance sensor array is a cost-effective, readily available possibility that can be replaced, for example, in particular for mobile robot applications, of providing the scanning information. In addition, the information content of scanning information of this form of detection unit enables features of the environment to be extracted in order to localize the detection unit.

According to one exemplary embodiment, the processing unit is designed to at least partially compensate for a perspective distortion of the scanning information using the position information. The localization of the detection unit can be made possible and/or improved by processing the scanning information. For example, the evaluation of equalized scanning information enables the extraction of information about inherent features of the environment, which can be compared with a database to deduce the position of the detection unit. Furthermore, distance estimates can also be improved, for example to avoid collisions with obstacles.

According to one exemplary embodiment, the device has a position detection unit that is designed to detect the position information, the device having the detection unit. The device can be designed as a vehicle, for example, which has the detection unit, for example a camera, for navigating on the surface. In order to take the position information into account and/or to manipulate the scanning information in order to localize the detection unit and thus also the device, the device additionally has a position detection unit for detecting the position information. The position detection unit can be designed, for example, as a multi-axis rotation angle sensor, which is arranged, for example, in the vicinity of the detection unit in order to detect the position information.

The combination of device with position detection unit and detection unit can be used for an automatically or autonomously driving robot. Through the combination of sensors in the position detection unit and detection unit and evaluation in the form of the processing unit of the device, a system can be created that can independently find its way around in an environment, for example with the help of a determination of its own position. By improving the localization using the position information from the position detection unit, a corresponding vehicle can orientate itself or at least better orientate itself in an unknown environment which, for example, has no markers.

According to one exemplary embodiment, the device is a vehicle with at least two sprung wheel segments, and the detection unit has a predetermined position relative to the at least two sprung wheel segments. By designing the device as a vehicle with at least two spring-loaded wheel segments, good driving characteristics of the device can be achieved, so that it can also be used on difficult terrain with uneven floors, for example. The device can in particular have three, four or more spring-loaded wheel segments. The predetermined position of the detection unit with respect to the at least two sprung wheel segments can be used to calculate the inclination of the detection unit by determining the deflection of the wheel segments, for example to improve the scanning information or its evaluation.

According to one exemplary embodiment, the position detection unit has at least two sensor elements, with the at least two sensor elements each being arranged on one of the at least two sprung wheel segments, and with the processing unit being designed to receive measured values from each of the at least two sensor elements, which are associated with a spring deflection of the wheel segments are correlated, and to calculate the attitude information based on a combination of the measured values.

By arranging the sensor elements directly on the sprung wheel segments, for example, simple and/or inexpensive sensor elements can be used. Instead of a central sensor, which has, for example, several measurement axes (which can, for example, carry out measurements in several spatial dimensions), several simple or single-axis sensors (which, for example, can only carry out measurements with regard to one spatial dimension) can be used whose measurement information is merged. Furthermore, more than one sensor element can also be arranged on each spring-loaded wheel segment, for example in order to create redundancy in applications that are particularly critical to safety. According to one exemplary embodiment, the at least two sensor elements are arranged on the wheel segments in such a way that when the wheel segments compress or rebound, there is a large change in the position of the sensor elements. Such an arrangement of the sensor elements on the wheel segments can improve the sensitivity of the position information with regard to a change in inclination of the detection unit, since even small changes in the compression or rebound of the wheel segments have an effect on the measured values of the sensor elements. The precision of the localization of the detection unit can thus in turn be improved.

According to one exemplary embodiment, the processing unit is designed to receive measured values from each of the at least two sensor elements and to determine information about the spring deflection of the at least two wheel segments based on the measured values, with the information about the spring deflection being information about a Wheel segments variable, distance of the respective wheel segment to the surface, and thus information about the inclination of the detection unit with respect to the surface.

For example, using stored geometry information of the wheel segments and the relative position of the detection unit with respect to the wheel segments, the processing unit can determine the deflection of the respective wheel segment by evaluating the measured values and thus the variable distance between the wheel segments and the surface due to the suspension. The distance between the wheel segments and the surface can in turn be used to calculate the inclination of the detection unit with respect to the surface using the predetermined relative position of the detection unit.

According to one exemplary embodiment, the at least two sensor elements have distance sensors and/or rotary encoders. Distance sensors and rotary encoders form robust and readily available sensor elements, which can be used, for example, in particular in vehicles such as mobile robot platforms. Due to the good availability of such sensors, a corresponding device can also be produced in large numbers. The use of distance sensors also makes it possible to directly determine the distance between the wheel segment and the surface in order to determine the position information of the detection unit. By determining an inclination of the wheel segments, together with known geometry information of the wheel segments, conclusions can be drawn about the deflection or the distance of the wheel segments to the surface via rotary encoders, in order in turn to derive the position information, ie, for example to determine information about the inclination of the detection unit with respect to the surface.

Distance sensors can have, for example, ultrasonic sensors and/or laser distance measurements or laser distance sensors. With these, for example as with rotary encoders, the inclined position of a vehicle and thus, for example, the inclination of the detection unit can be determined.

According to one embodiment, the device is a vehicle for a sorting system. By designing the device as a vehicle, for example with a detection unit and position detection unit, a robot that moves autonomously or automatically can be implemented. Such a device according to the invention can have great advantages with regard to use in a sorting system, for example through improved localization by taking into account the position information, so that trajectory planning and collision avoidance through improved position determination of the individual robots, for example in particular without the complex and costly Markers can be used.

According to one exemplary embodiment, the vehicle is designed to move autonomously. Autonomous locomotion can be made possible and/or improved by the improved position determination according to the invention, since the risk of collisions can be reduced, for example due to more precise information about one's own position.

According to one exemplary embodiment, the method also includes manipulating the scanning information using the position information in order to obtain manipulated scanning information and evaluating the manipulated scanning information with regard to the localization of the detection unit relative to the surface.

The manipulation of the scanning information using the location information can enable the extraction of features of the environment from the scanning information, and/or the evaluation of the features, which can for example be inherent features of the environment, such as patterns in a ground surface, with regard to the shape of the features and /or for example in particular the relative location or positions of the features to each other. By improving the scanning information using the position formation, it is possible to determine absolute distances, ie distances that are not distorted by an inclination of the detection unit, which in turn can be used to determine the position by means of a reference, ie for example by means of a database comparison.

Figure short description

Examples according to the present disclosure are explained in more detail below with reference to the accompanying figures. With regard to the schematic figures shown, it is pointed out that the function blocks shown are to be understood both as elements or features of the device according to the disclosure and as corresponding method steps of the method according to the disclosure, and corresponding method steps of the method according to the disclosure can also be derived therefrom. Show it:

1 shows a schematic side view of a device according to an embodiment of the present invention;

2 shows a schematic side view of a device according to an exemplary embodiment of the present invention, the device being designed as a vehicle and having the detection unit and the position detection unit;

3a is a schematic side view of a sprung wheel segment in the neutral position according to an embodiment of the present invention;

FIG. 3b shows a schematic side view of the sprung wheel segment from FIG. 3a in an exemplary compressed state according to an exemplary embodiment of the present invention; FIG.

FIG. 3c shows a schematic side view of the sprung wheel segment from FIG. 3a in an exemplary, rebound state according to an exemplary embodiment of the present invention; FIG.

4 shows a flowchart of a method according to an embodiment of the present invention; 5a is a schematic side view of another sprung wheel segment in the neutral position according to an embodiment of the present invention;

FIG. 5b shows a schematic side view of the further sprung wheel segment from FIG. 5a in an exemplary compressed state according to an exemplary embodiment of the present invention; FIG.

FIG. 5c shows a schematic side view of the further sprung wheel segment from FIG. 5a in an exemplary, rebounded state according to an exemplary embodiment of the present invention; FIG.

Fig. 6 shows schematic representations of possible perspective distortions of the scan information addressed by embodiments of the present invention; and

Fig. 7 is a schematic side view of a sprung wheel segment with a counter-sprung swing arm according to an embodiment of the present invention.

Detailed description of the examples according to the figures

Before exemplary embodiments of the present invention are explained in more detail below with reference to the drawings, it is pointed out that identical, functionally identical or equivalent elements, objects and/or structures in the different figures are provided with the same or similar reference symbols, so that the Embodiments illustrated description of these elements is interchangeable or can be applied to each other.

1 shows a schematic side view of a device according to an embodiment of the present invention. Fig. 1 shows a device 100 with a processing unit 110 which is designed to obtain scanning information 120 _a of a two-dimensional scan 120 _b of a surface 130 and also position information 120 _c (e.g. angle information a) to obtain an inclination (e.g. angle a) of a detection unit 120 providing the two-dimensional scanning 120 _b with respect to the surface 130. The position information can indicate the inclination at which With regard to the surface, the scanning information 120 _a was obtained at the time of scanning 120 _b . For example, the position information 120 _c can indicate which position or inclination a detection unit 120, which is optionally part of the device 100, has at this time. The processing unit 110 is also designed to evaluate the scanning information 120 _a using the position information 120 _c with regard to a localization of the detection unit 120 relative to the surface 130 .

The detection unit 120 can be part of a drone or part of a mobile robot, for example, which navigates over a ground surface 130 . The detection unit 120 can have a camera and/or a laser distance sensor array. The detection unit can also be an area camera or a line camera, but can also be set up for other, preferably optical, scanning of the surface, for example by means of RADAR (Radio Detecting and Ranging) or LiDAR (Light Detecting and Ranging).

Movement and/or acceleration of detection unit 120, e.g. due to deflection of a vehicle having detection unit 120, e.g. when driving through a curve or when the speed is increased or decreased relative to surface 130, can lead to the inclination of the Detection unit 120 come. As a result, the scanning _120b of the surface 130 cannot, for example, take place orthogonally or perpendicularly to the surface 130, so that the scanning information 120a has _a perspective distortion due to the inclination. By providing the position information 120 _c , that is, for example, information about the angle a, such a perspective distortion can also be taken into account or at least partially compensated for when evaluating the scanning information 120 _a .

As a result, an improved determination of environmental features can be carried out by, for example, distances and positions of inherent features of the environment, which can be contained in the scanning information 120 _a , being determined by correcting the distortion using the position information 120 _c . Such a form of environment classification, for example mapping, can be used, for example, to locate detection unit 120 using a priori information, by detecting features or feature clusters, such as the arrangement of a large number of features in a specific pattern at specific distances from one another . By compensating for the inclination using the position information, features can be used to determine the position that are little or not robust to perspective distortions, as is known from QR codes, for example. This allows a variety of features to be used, which makes localization flexible.

2 shows a schematic side view of a device according to an exemplary embodiment of the present invention, the device being designed as a vehicle and having the detection unit and the position detection unit. 2 shows a device 200, which is designed as a vehicle, for example a mobile robot platform, with a processing unit 110, a detection unit 120 and a position detection unit 210. The vehicle 200 has wheel segments 220 which are spring-loaded. However, as shown in FIG. 2 , not all wheel segments have to be sprung, so the vehicle 200 also has unsprung wheel segments 230 . It should be noted that only one of the sprung wheel segments 220 is shown in the side view. Furthermore, all wheel segments can also be spring-loaded. Furthermore, the sprung wheel segments need not all be located at one end of the vehicle 200, the illustration with sprung wheel segments on one side of the vehicle is merely an example. The spring-loaded wheel segments 220 are shown in a spring-loaded state, for example due to an acceleration of the device 200, for example in the x-direction (oriented in the negative x-direction). FIG. 2 shows an embodiment of the position detection unit 210 with an optional, central sensor element 210i. As an alternative or in addition, the position detection unit 210 can have sensor elements 210 ₂ which are each arranged on the sprung wheel segments 220 . The sensor elements can include, for example, gyroscopes, ultrasonic sensors, laser distance sensors or sensor arrays or incremental encoders.

Processing unit 110 is designed to receive scanning information 120 _a of a two-dimensional scan 120 _b of a surface 130 and position information 120 _c , i.e. position information 120 _ci from central sensor element 210i and/or position information 120 _C2 from sensor elements 210 ₂ , indicating an inclination (e.g. a) of the detection unit 120 providing the scan _120b with respect to the surface 130. The processing unit 110 can be designed to receive position information 120 _c which has at least two measured values of the sensor elements 210 , the two measured values having at least parts of information about the inclination of the detection unit 120 . In the case of a vehicle 200 that has only two sprung wheel segments 220, for example a sprung front axle with two wheel segments 220 and an unsprung rear axle with at least one wheel segment 230, the at least two measured values can be provided by at least two sensor elements 210i, which are attached to each a spring-loaded wheel segment 220 (e.g. at least one measured value from each sensor element 210i). In this case, position information of vehicle 200 and thus also of detection unit 120 can be provided by evaluating the at least two measured values and, for example, a known distance, for example constant due to the lack of suspension, of the at least one unsprung wheel segment 230 from surface 130 .

In a vehicle 200, which has at least three sprung wheel segments 220, for example one sprung wheel segment 220 on the front axle and two sprung wheel segments 220 on the rear axle, or two sprung wheel segments 220 on both the front and rear axles, the processing unit 110 can be designed to receive position information 120 _C1 which has at least three measured values, the three measured values having at least parts of information about the inclination of the detection unit 120 . The at least three measured values can be provided by at least three sensor elements 210i, which are each arranged on one of the sprung wheel segments 220 (e.g. at least one measured value from each sensor element 210i). With the at least three measured values, information about an inclination of the vehicle 200 and thus of the detection unit 120 can in turn be determined.

In both cases, the at least two or at least three measured values can alternatively or additionally be provided by a central sensor element 2102, which can record the measured values with regard to a number of measurement axes, ie with regard to different spatial directions.

The processing unit 110 can thus manipulate the scanning information 120 _a using the position information 120 _o in order to obtain manipulated scanning information and execute this with regard to a localization of the detection unit 120 and in this case also of the vehicle 200 . The manipulation can include _a compensation or at least a partial compensation of a perspective distortion of the scanning information 120a. The scanning information 120a can, for example _, be distorted by the inclination (eg angle α) of the detection unit 120 with respect to the surface 130, which in turn can be compensated for by the processing unit 110 using the position information _120c . In other words, the sample information 120a can be equalized _, for example. For this purpose, for example, the scanning information 120 _a can be rectified by the processing unit 110 .

According to FIG. 2 , detection unit 120 has a predetermined position relative to the at least two sprung wheel segments 220 . As a result, when using the sensor elements 210 ₂ , for example, by evaluating the position information 120 _C2 , taking into account the geometric distances and angles between the sensor elements 210 ₂ and the detection unit 120 , an inclination of the detection unit 120 can be calculated back.

Sensor elements 210 ₂ can generate measured values that are correlated with a spring deflection of wheel segments 220, so that position information 120 _C2 about wheel segments 220 and thus, due to the predetermined relative position of detection unit 120 with respect to the at least two sprung wheel segments 220, position information 120 _c over the inclination of the detection unit 120 with respect to the surface 130 has. The arrangement of the sensor elements 2102 can be selected such that when the wheel segments 220 compress or rebound, there is a large change in the position of the sensor elements 2102 in order to also be able to detect slight inclinations and changes in position of the detection unit 120 and thus, for example, be able to compensate. In terms of vibrations, the sensor elements can thus be arranged at locations with a large amplitude.

In the following, examples of states of the sprung wheel segments according to the invention will be explained in more detail with reference to FIGS. 3a, 3b and 3c. In exemplary embodiments, FIGS. 3a, 3b and 3c can show a detailed view of the spring-loaded wheel segments 220 previously explained, for example with reference to FIG. 2, together with the sensor elements in FIG. 3 in the form of rotary encoders in different states. Fig. 3a shows a schematic side view of a sprung wheel segment in a neutral position, Fig. 3b shows a schematic side view of the sprung wheel segment from Fig. 3a in an exemplary compressed state, and Fig. 3c shows a schematic side view of the sprung wheel segment from Fig. 3a in an exemplary rebounded state Condition. Figures 3a-c show spring-loaded wheel segments 220, which swing arms 310, springs 320 and rotary encoder 330 have. The wheel segments 220 also have pivot points 340 which form an axis of rotation of the wheel links 310 with respect to the deflection of the springs 320 . For example, due to the predetermined relative position of the detection unit 120 with respect to the wheel segments 220 , the rotary encoders 330 can indicate at least parts of information about the position of the detection unit, e.g. camera, with respect to the surface 130 . For example, each of the rotary encoders 330 can indicate local tilt or rotation. Such partial information can be used, for example, using at least two (e.g. together with geometrically determined, known information such as the distance between an unsprung wheel segment 230 and the surface 130) or at least three spaced-apart rotary encoders 330 or other sensor elements 210, to determine a tilt at another location, such as the detection unit 120, taking into account the geometric arrangement or position, such as by considering that a plane subject to the tilt can be determined by three points in space.

In other words, it is possible to also determine the inclination locally at the location of the detection unit 120, for example using a single sensor element 210. If a plurality of distributed sensor elements 210 are positioned, they can be jointly evaluated by taking the distribution geometry into account.

3a shows an initial position of the vehicle, which has the wheel segment 220, with the spring of the suspension 320 being in the neutral position, so that no image compensation, for example due to compression or rebound, need be necessary. FIG. 3b shows a state of the vehicle in which the spring of suspension 320 is compressed, so that the area of the vehicle shown is lower than other areas, for example, and rotation angle sensor 330 detects inclination information that differs from the reference position in FIG. 3a. The detection unit, e.g. a camera, can be located closer to the ground 130 than in Fig. 3a (see e.g. Fig. 5b). 3c shows a state of the vehicle in which the spring of the suspension 320 is stretched out, so that the area of the vehicle is higher than, for example, other areas and the angle of rotation sensor 330 detects different, deviating information about the inclination. Reference is also made to the examples in FIG. 2 in this regard. the The detection unit can be located further away from the ground (see, for example, FIG. 5c) if it is arranged away from the pivot point at a corner of the vehicle or the wheel segment 220 or the swing arm 310 of the vehicle.

FIGS. 3a-c are intended to clarify the basic idea of exemplary embodiments according to the present invention, which consists in obtaining, for example, precise information about the, for example, precise deflection of each wheel of the vehicle. For this purpose, exemplary embodiments provide the rotary encoder 330, which is attached to the rockers 310 of the wheel segments, for example the wheel suspension.

The spring deflection can be determined via the angle at pivot point 340 . By combining the measurements of the different wheels, or to put it another way, the measured values of the different rotary encoders 330 of the sprung wheel segments 220, the position of the vehicle in space can be precisely determined, for example. In exemplary embodiments, it can be advantageous to provide at least three measurement points in order to be able or to determine the position of a plane in space, and thus, for example, the position of the detection unit and therefore of the vehicle. Through a process known in image processing as rectification, images can be transformed as if they had been taken from a different pose in space. With this technology, the measured values of the recording unit, for example in the form of an optical sensor, can be equalized, i.e. at the end, i.e. after equalization or rectification, for example, they look exactly as if they had been recorded from a non-compressed state.

While some embodiments contemplate use of rectification, which generally relates to images, apparatus and methods in accordance with the present invention are not limited to the exclusive use of images. Within the framework of concepts according to the invention, other forms of scanning information can also be manipulated, that is to say rectified, for example, using the position information. A method according to the invention can accordingly also equalize scanning information or measurements, for example from a laser distance sensor array. In the case of one-dimensional scans, or to put it another way in one-dimensional cases, a measurement or scan can be interpreted as an image line. It should also be pointed out that the inclined position of the vehicle or the inclination of the detection unit can be measured using various types of distance sensors, such as ultrasonic sensors or laser distance measurements or laser distance sensors, e.g. instead of the rotary encoder 330 shown in Figures 3a-c , can be determined.

In addition, the spring deflection could also be determined by measuring directly on/in the spring/damper unit, e.g. a wheel segment 220. However, determining the spring deflection using a sensor element 2102 on a swing arm 310 of a wheel segment 220 can have the advantage of being able to be implemented with less effort and at lower cost. Furthermore, a measurement of the angle, that is to say for example the angle of rotation of the swing arm 310 of the wheel segment 220 by the angle of rotation sensor 330, can be possible with smaller errors and/or tolerances.

4 shows a flow chart of a method according to an embodiment of the present invention. In a step 410, the method 400 includes obtaining scanning information for a two-dimensional scan of a surface, in a step 420 obtaining position information that indicates an inclination of a detection unit providing the two-dimensional scanning with respect to the surface, and in a further step 430 an evaluation the scanning information using the position information regarding a localization of the detection unit relative to the surface. It should be noted that steps 410 and 420 may be performed in any order and/or simultaneously since both steps may provide inputs to step 430 independently.

The method 400 may optionally include manipulating the scan information using the location information to obtain manipulated scan information. In order to take the manipulated distance information into account, step 430 can include an evaluation of the manipulated scanning information with regard to the localization of the detection unit relative to the surface.

The position and position of the detection unit when there is a change in the deflection state of spring-loaded wheel segments is to be explained in more detail with reference to the following FIGS. 5a-c. FIGS. 5a-c show spring-loaded wheel segments, which have swing arms 310, and a detection unit, which is designed as a camera 510. In FIGS. 5a-c, the camera 510 is as it is, for example, in reality or in many practical implementations is the case, firmly connected to a housing and thus, for example, in turn to the wheel swing arm 310. This means that the camera 510 cannot, for example, be mounted so that it is no longer aligned perpendicularly to the ground surface when the rocker arm 310 is inclined or whether a changed spring compression state has a variable orientation or inclination to the ground.

The wheel segments also have pivot points 340, which form an axis of rotation of the swing arm 310 with respect to the deflection of the springs. In comparison to Fig. 3a-c, the suspension is not shown explicitly for the sake of simplicity, with the exception of the point of application 520 of the suspension on the swing arm 310. Figures 5a-c can form a simplified representation of Figures 3a-c, with the detection unit in Form of a camera 510 is also shown. A rotary encoder analogous to FIG. 3a-c is not shown explicitly for reasons of simplification, but according to the disclosure it can be present. Furthermore, FIGS. 5a-c show schematic images 530a-c, based on scanning by the detection unit, ie the camera 510, depending on the respective state of the suspension of the wheel segment.

FIG. 5a shows a schematic side view of a sprung wheel segment in the neutral position, analogous to FIG. 3a. In the case of a flat ground surface, the camera 510 is parallel to the surface, so that an undistorted image 530a can be recorded.

FIG. 5b shows a schematic side view of the sprung wheel segment from FIG. 5a in an exemplary compressed state, analogous to FIG. 3b. Due to the compressed state, the camera 510 is closer to the ground surface and has a tilt angle with respect to the ground surface. For example, when considering an individual rocker 310, a maximum of two degrees of freedom can change, namely the distance to the ground if the camera 510 is not attached exactly in the middle of the axis or pivot point 340, and the angle of the camera 510, e.g. the viewing angle of the camera 510 with respect to the ground surface. In a construction with several rockers 310, e.g change, namely the roll and pitch angle of the camera 510, and the distance to the ground surface, ie, for example, to the ground. To put it simply, this means, for example, concretely in FIG. 5b or the image 530b, that when the swing arm 310 is at an angle, the camera 510 is also aligned at an angle to the ground or captures it. Accordingly, the image 530b is distorted in comparison to the image 530a in that, for example, a trapezoidal image 530b is created from the rectangular image 530a.

FIG. 5c shows a schematic side view of the sprung wheel segment from FIG. 5a in an exemplary, rebounded state, analogous to FIG. 3c. Due to the extended state, the camera 510 is further away from the ground surface and has a tilt angle with respect to the ground surface. Accordingly, image 530c is also distorted compared to image 530a.

Possible distortions of the scanning information, that is, for example, of the images 530a-c, are to be explained in more detail with reference to FIG. Although the effects are shown individually, they can also occur in combination, which does not conflict with the exemplary embodiments described herein. FIG. 6 shows reference scanning information 610, which was recorded, for example, by a camera 510 that is attached to a swing arm in the neutral position, for example analogously to FIG. 5a.

An increase 620 in the distance between the detection unit and the surface can lead to a reduction in the size of an image section of the reference scanning information 610, i. This means that the object area actually recorded is only part of the overall picture. This is illustrated with result sample information 620a.

A reduction 630 in the distance between the acquisition unit and the surface can lead to an enlargement of an image detail of the reference scanning information 610, ie only parts of the reference scanning information 610 are acquired, for example. This is illustrated with result sample information 630a.

A tilting 640 of the detection unit with respect to a first axis can lead to a distortion of an image detail of the reference scanning information 610 with respect to the first axis. This is illustrated with result sample information 640a. A tilting 650 of the detection unit can also take place with respect to a second axis, which is possibly perpendicular to the first axis. For example, one of the axes may be at least partially determined by pivot 340, which is based on an axis of rotation in the three-dimensional body of the two-dimensional side sectional views shown can be understood as an axis. The result of a tilting about the second axis is shown as an example with the result scanning information 650a.

The changed scanning information 620a, 630a, 640a and/or 650a can be corrected individually or in combination with exemplary embodiments described herein, taking into account the position information, wherein the evaluation of the scanning information described here can include equalization and/or scaling using the exemplary rectification.

The tilting with respect to a first and/or second axis can result, for example, from the above-described roll and/or pitch angle of a camera with respect to a ground surface. This type of tilting and also changes in distance can occur, for example, when accelerating or braking and/or when cornering a spring-loaded vehicle. It should also be pointed out that any overlaying of the distortions and/or enlargements and/or reductions in the scanning information is possible, for example particularly with regard to vehicles with a large number of spring-loaded wheel segments. In addition, the positioning of the camera 510 on the swing arm 310 is only to be seen here as an example in order to explain concepts according to the invention. In the case of a vehicle with several sprung wheel segments, the camera can also be located centrally in the vehicle and does not have to be attached to one of the individual swingarms 310 . The deflection of the individual wheel segments can then result in a superimposition of the distortions explained in the form of changes in distance and/or tilting for camera 510 or for an image recorded by the camera, e.g. due to the connection between the individual wheel swingarms and the chassis of the vehicle on which in turn the camera can be attached.

6 makes it clear that an evaluation of the scanning information according to the disclosure using position information, for example a rectification of an image recorded by a camera 510 using the angle information from rotary encoders, can bring great advantages, for example to compensate for undesired distortions. In order to ensure good driving characteristics, the use of sprung vehicles can be indispensable, which, however, can increase the problem of distorted scanning information due to the extended driving dynamics. However, due to distortion of the scanning information, localization using environmental features, for example, can become difficult or even impossible, since the features may not be detected due to the distortion can be, which is why concepts according to the invention using the position information, eg for image correction, can offer great advantages.

FIG. 7 shows a schematic side view of a sprung wheel segment with a counter-sprung swing arm according to an exemplary embodiment of the present invention. The swing arm 310 has a fulcrum 340 and is counter-sprung against a load 710 with weight G via a counter-spring system 720 . In exemplary embodiments, according to FIGS. 3a-c, a rotary encoder can be arranged on the side of counter-springing 720 with respect to pivot point 340, that is to say on the right in the figure. When the rocker 310 is loaded with a load 710, the spring state of the counter-springing system 720 can change, which can lead to the rocker 310 tilting. Such an inclination can be detected by a rotary encoder.

In such a case, the load can, for example, form the chassis of a vehicle which, for example, has the detection unit that is loaded or unloaded, for example. Even if a vehicle is loaded symmetrically so that all sprung wheel segments of the vehicle compress or rebound in the same way, according to the invention, angle of rotation sensors on the wheel swing arms can detect inclination information based on the inclination of wheel swing arm 310, due to load 710 and of counter-springing 720. By, for example, combinatorial evaluation of the inclination information from the rotary encoders, ie, for example, the angle of swingarms 310 with respect to hinge points 340, an inclination of the detection unit can be calculated back.

If, for example, all rotary encoders of different wheel segments have the same angle of inclination of the rocker arms 310, it can be concluded that the detection unit is aligned parallel to the ground surface. At the same time, a spring deflection of the individual wheel segments can be calculated back from the inclination of the individual rotary encoders and, for example, known geometry parameters of the wheel segments, so that a change in the distance of the detection unit with respect to the ground surface (e.g. according to Fig. 6 image 620a / 630a) can be concluded. This in turn can be used to manipulate, for example scaling, the scanning information.

It should be pointed out again that any combination of distance changes and tilting or distortions can also be detected or compensated for in this way be able. In addition, it should be noted that Fig. 7 represents only one example of wheel segment designs according to the invention and that load 710 and counter-springing 720 can also be interchanged, analogous to positioning the rotary encoder on one side or the other of pivot point 340 on rocker 310 .

Conclusions and further remarks

In very general terms, embodiments of the present invention provide a way of compensating for perspective distortions. As a result, scanning information from the detection unit, for example measurement data from an optical sensor, can be used for methods such as localization methods, which are not robust to this type of distortion, in contrast to QR codes, for example. Although this can be of particular interest or advantage for image sensors, the device and method according to the invention are not limited to the use of image sensors. Concepts according to the invention can, for example, simplify the use of optical sensors for localization, e.g. in applications in which strong deflection is to be expected. Alternatively or additionally, concepts according to the invention can increase the accuracy or the accuracy to be expected, for example of the localization of the detection unit or the vehicle.

Embodiments according to the present invention are based on the determination of a position of a vehicle in space based on the spring deflection, for example using rotary encoders on the swingarms of wheel segments, for example wheel suspensions.

Technical application areas of embodiments according to the present invention can form the localization of automatic or autonomous vehicles or robots via optical sensors.

In embodiments according to the present invention, the processing unit can be implemented by any suitable circuit structures, for example microprocessor circuits, ASIC circuits, CMOS circuits and the like. In examples, the processing unit may be implemented as a combination of hardware structures and machine-readable instructions. For example, the processing unit can have a processor and a memory device that store bare instructions that, when executed by the processor, provide the described functionalities and result in the performance of methods described herein. In examples, the memory means may be implemented by any suitable memory device, such as ROM, PROM, EPROM, EEPROM, flash memory, FRAM (ferroelectric RAM), MRAM (magnetoresistive RAM), or phase change RAM.

All lists of the materials, environmental influences, electrical properties and optical properties listed here are to be regarded as examples and not as conclusive.

Although some aspects have been described in the context of a device, it is understood that these aspects also represent a description of the corresponding method, so that a block or a component of a device is also to be understood as a corresponding method step or as a feature of a method step. Similarly, aspects described in connection with or as a method step also constitute a description of a corresponding block or detail or feature of a corresponding device. Some or all of the method steps may be performed by hardware apparatus (or using a hardware Apparatus), such as a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, some or more of the essential process steps can be performed by such an apparatus.

Depending on particular implementation requirements, embodiments of the invention may be implemented in hardware or in software. Implementation can be performed using a digital storage medium such as a floppy disk, DVD, Blu-ray Disc, CD, ROM, PROM, EPROM, EEPROM or FLASH memory, hard disk or other magnetic or optical Memory are carried out on which electronically readable control signals are stored, which can interact with a programmable computer system in such a way or interaction that the respective method is carried out. Therefore, the digital storage medium can be computer-readable. Thus, some embodiments according to the invention comprise a data carrier having electronically readable control signals capable of interacting with a programmable computer system in such a way that one of the methods described herein is carried out.

In general, embodiments of the present invention can be implemented as a computer program product with a program code, wherein the program code is effective to perform one of the methods when the computer program product runs on a computer.

The program code can also be stored on a machine-readable carrier, for example.

Other exemplary embodiments include the computer program for performing one of the methods described herein, the computer program being stored on a machine-readable carrier.

In other words, an exemplary embodiment of the method according to the invention is therefore a computer program that has a program code for performing one of the methods described herein when the computer program runs on a computer.

A further exemplary embodiment of the method according to the invention is therefore a data carrier (or a digital storage medium or a computer-readable medium) on which the computer program for carrying out one of the methods described herein is recorded. The data carrier, digital storage medium, or computer-readable medium is typically tangible and/or non-transitory.

A further exemplary embodiment of the method according to the invention is therefore a data stream or a sequence of signals which represents the computer program for carrying out one of the methods described herein. For example, the data stream or sequence of signals may be configured to be transferred over a data communication link, such as the Internet. Another embodiment includes a processing device, such as a computer or programmable logic device, configured or adapted to perform any of the methods described herein.

Another embodiment includes a computer on which the computer program for performing one of the methods described herein is installed.

A further exemplary embodiment according to the invention comprises a device or a system which is designed to transmit a computer program for carrying out at least one of the methods described herein to a recipient. The transmission can take place electronically or optically, for example. For example, the recipient may be a computer, mobile device, storage device, or similar device. The device or the system can, for example, comprise a file server for transmission of the computer program to the recipient.

In some embodiments, a programmable logic device (e.g., a field programmable gate array, an FPGA) may be used to perform some or all of the functionality of the methods described herein. In some embodiments, a field programmable gate array may cooperate with a microprocessor to perform any of the methods described herein. In general, in some embodiments, the methods are performed by any hardware device. This can be universally replaceable hardware such as a computer processor (CPU) or hardware specific to the process such as an ASIC.

The devices described herein may be implemented, for example, using hardware apparatus, or using a computer, or using a combination of hardware apparatus and a computer.

The devices described herein, or any components of the devices described herein, may be implemented at least partially in hardware and/or in software (computer program).

The methods described herein may be implemented, for example, using hardware apparatus, or using a computer, or using a combination of hardware apparatus and a computer. The methods described herein, or any components of the methods described herein, may be performed at least in part by hardware and/or by software.

The embodiments described above are merely illustrative of the principles of the present invention. It is understood that modifications and variations to the arrangements and details described herein will occur to those skilled in the art. Therefore, it is intended that the invention be limited only by the scope of the following claims and not by the specific details presented in the description and explanation of the exemplary embodiments herein.

Claims

patent claims

1. Device (100, 200) with: a processing unit (110) which is designed to obtain scanning information (120 _a ) of a two-dimensional scan (120 _b ) of a surface (130); and obtaining position information (120 _c ) indicating an inclination of a detection unit (120, 510) providing the two-dimensional scan (120 _b ) with respect to the surface (130); and evaluating the scanning information (120 _a ) using the position information (120 _c ) with regard to a localization of the detection unit (120, 510) relative to the surface (130).

2. Device (100, 200) according to claim 1, wherein the processing unit (110) is designed to manipulate the scanning information (120 _a ) using the position information (120 _c ) in order to obtain manipulated scanning information; and carry out an evaluation of the manipulated scanning information with regard to the localization of the detection unit (120, 510) relative to the surface (130).

3. Device (100, 200) according to one of the preceding claims, wherein the processing unit (110) is designed to carry out a rectification of the scanning information (120 _a ) based on the position information (120c).

4. Device (100, 200) according to one of the preceding claims, wherein the detection unit (120, 510) has a camera (510) and/or a laser distance sensor array.

5. Device (100, 200) according to one of the preceding claims, wherein the processing unit (110) is designed to at least partially compensate for a perspective distortion of the scanning information (120 _a ) using the position information (120 _c ).

6. Device (100, 200) according to one of the preceding claims, wherein the device (100, 200) has a position detection unit (210) which is designed to detect the position information (120 _c ) and wherein the device (100, 200 ) has the detection unit (120, 510).

7. Device (100, 200) according to claim 6, wherein the device (100, 200) is a vehicle with at least two sprung wheel segments (220) and wherein the detection unit (120, 510) has a predetermined relative position with respect to the at least two sprung wheel segments (220).

8. The device (100, 200) according to claim 7, wherein the position detection unit (210) has at least two sensor elements (210 ₂ ), wherein the at least two sensor elements (2102) are each arranged on one of the at least two sprung wheel segments (220); and wherein the processing unit (110) is designed to receive measured values from each of the at least two sensor elements (210 ₂ ), which are correlated with a spring deflection of the wheel segments (220), and to calculate the position information (120 _c ) based on a combination of the calculate measurements.

9. The device (100, 200) according to claim 8, wherein the at least two sensor elements (210 ₂ ) are arranged on the wheel segments (220) such that when the wheel segments (220) compress or rebound, there is a large change in the position of the sensor elements (210 ₂ ). he follows.

10. Device (100, 200) according to one of claims 8 or 9, wherein the processing unit (110) is designed to receive measured values from each of the at least two sensor elements (210 ₂ ); and to determine information about the spring deflection of the at least two wheel segments (220) based on the measured values, the information about the spring deflection including information about a distance of the respective wheel segment from the surface (130) that can be changed by the suspension of the wheel segments (220), and thus information about the inclination of the detection unit (120, 510) with respect to the surface (130).

11. Device (100, 200) according to claim 10, wherein the at least two sensor elements (2102) have distance sensors and/or rotary encoders.

12. Device (100, 200) according to any one of the preceding claims, wherein the device (100, 200) is a vehicle (200) for a sorting system.

13. Device (100, 200) according to claim 12, wherein the vehicle (200) is designed to move autonomously.

14. Method (400) having the following characteristics:

obtaining (410) scan information (120 _a ) of a two-dimensional scan (120 _b ) of a surface (130); and

Obtaining (420) position information (120 _c ) indicating an inclination of a detection unit (120, 510) providing the two-dimensional scanning (120 _b ) with respect to the surface (130); and

Evaluation (430) of the scanning information (120 _a ) using the position information (120 _c ) with regard to a localization of the detection unit (120, 510) relative to the surface (130).

The method (400) of claim 14, the method further comprising:

manipulating the scan information (120 _a ) using the location information (120c) to obtain manipulated scan information; and

Evaluating the manipulated scanning information with regard to the localization of the detection unit (120, 510) relative to the surface (130).

16. Computer program with a program code for carrying out the method (400) according to one of claims 14 or 15, when the program runs on a computer.