DE102018207857A1 - Method and positioning system for transforming a position of a vehicle - Google Patents

Abstract

Method, control unit and positioning system for transforming a position of a vehicle (10) from a first coordinate system (20) into a second coordinate system (40), which detects (S1) at least two location vectors (22, 24, 26) with respect to the vehicle ( 10) in the first coordinate system (20) with a first position detection system at at least two different vehicle locations (12, 14, 16), detecting (S2) at least two location vectors (42, 44, 46) relative to the vehicle (10) in the second coordinate system (40) having a second position detection system at the at least two different vehicle locations (12, 14, 16), calculating (S5) transformation parameters between the first coordinate system (20) and the second coordinate system (40) based on the at least two location vectors (22, 24, 26) in the first coordinate system (20) and the at least two location vectors (42, 44, 46) in the second coordinate system (40) and calculating (S6) of the position of the vehicle (10) in the second coordinate system (40) by means of transforming the position of the vehicle (10) from the first coordinate system (20) in the second coordinate system (40) with the calculated transformation parameters or are set up.

Description

Technical part

The invention relates to a method, a control unit and a positioning system for transforming a position of a vehicle, wherein the method, the control unit and the positioning system comprises detecting or determining location vectors of the vehicle in a coordinate system with a position detection system.

State of the art

From the DE 10 2016 108 446 A1 It is known to determine the whereabouts of a transport vehicle with an antenna mounted on the transport vehicle and by means of transponders fixed in a roadway.

However, with a transponder network arranged in a road surface, a location of a vehicle can only be determined within the spatial extent of the transponder network. Outside a locally limited transponder network, however, a position determination of a vehicle is not possible.

Summary of the invention

The invention therefore provides solutions to design the position determination of a vehicle more efficient and spatially more flexible, with an increase in efficiency and greater spatial flexibility can be achieved in particular by reducing the dependence of the position determination of a single position detection system.

Such a solution for a method of transforming a position of a vehicle between a first coordinate system and a second coordinate system comprises detecting at least two location vectors with respect to the vehicle in the first coordinate system with a first position detection system at at least two different vehicle locations and detecting at least two location vectors with respect to the vehicle in the second coordinate system with a second position detection system at the at least two different vehicle locations. Furthermore, the method comprises calculating transformation parameters between the first coordinate system and the second coordinate system based on the at least two location vectors in the first coordinate system and the at least two location vectors in the second coordinate system and calculating the position of the vehicle in one of the first coordinate system and the first coordinate system second coordinate system by transforming the position of the vehicle between the first coordinate system and the second coordinate system with the calculated transformation parameters.

A transformation of the position of the vehicle between the first coordinate system and the second coordinate system may include a transformation of the position of the vehicle from the first coordinate system into the second coordinate system or a transformation of the position of the vehicle from the second coordinate system into the first coordinate system.

The vehicle to be determined in its position by transformation can in principle be any vehicle, which can be, in particular, a rail-bound or non-rail-bound transport vehicle, which can be designed to transport containers, material or goods. Alternatively or additionally, the vehicle may be a work vehicle, for example, the vehicle may be a construction machine.

The vehicle may, for example, move in a container port, in a railway station, on a factory premises, in a factory hall and / or on a construction site, whereby the vehicle may also move from one of these locations to another of these locations.

By transforming a position of the vehicle, a transformation of a vehicle reference point, for example a center of the rear axle or another vehicle axle, from the first coordinate system to the second coordinate system or vice versa can be understood. The vehicle reference point can basically be any point defined in a vehicle coordinate system, which can be defined within the vehicle, on the vehicle or even in the surroundings of the vehicle, and whose position vector in the first coordinate system with the first position detection system or its position vector in the second coordinate system with the second position detection system can be determined. The vehicle coordinate system may be a coordinate system bound to the vehicle itself.

For the transformation, coordinates of a reference point of the first or second position detection system, that is, a point on which the corresponding position detection coordinates coordinates, may be known as an offset in the vehicle coordinate system. The reference point of a position detection system may be the origin of the vehicle coordinate system, where the offset is zero, or may be different than the origin of the vehicle coordinate system, the offset defining an offset between the reference point about the origin of the vehicle coordinate system.

The transformation can have an automatic transformation, that is to say in particular a transformation without the a priori knowledge of control points. Such a transformation can therefore also be referred to as an automatic transformation or an automatic calibration of a coordinate transformation between two coordinate systems. The two coordinate systems therefore do not have to be calibrated, and in particular a measurement of a position of a position detection sensor on the vehicle with respect to the vehicle reference point can be dispensed with.

The coordinate transformation can be a two-dimensional similarity transformation with four transformation parameters. The four transformation parameters can comprise a rotation angle, a translation vector, which can have two translation parameters, and a scale factor, wherein in particular the scale factor can be known, that is, for example, can be substantially equal to one. The position of the vehicle to be transformed may be a current location of the vehicle or a point along a vehicle trajectory that has been traveled or has to be traveled.

The first coordinate system may be a local coordinate system, such as a transponder system, and the second coordinate system may be a global coordinate system, such as a satellite navigation coordinate system, or vice versa. The transponder system may have a transponder network, in particular an RFID network, arranged in a road surface.

The global coordinate system can also be referred to as a higher-level coordinate system. The terms "local", "global" or "superordinate" can be understood hierarchically in terms of their spatial extent for a corresponding position determination of the vehicle. Thus, the position determination in a local coordinate system can be locally limited, while the position determination in a global coordinate system can be essentially spatially unlimited. The terms "local," "global," and "parent," respectively, may also be understood to be functional, where the local coordinate system may cover a gap in position determination with the global coordinate system. For example, a transponder system as a local position sensing system in a building can compensate for unavailability of a satellite positioning system as a global position sensing system. The first coordinate system can therefore also be an indoor coordinate system and the second coordinate system can be an outdoor coordinate system.

A corresponding position vector in one of the coordinate systems may indicate a position or location of the vehicle in one of the coordinate systems. The corresponding location vector may have coordinates with respect to one of the coordinate systems. The location vectors in the various coordinate systems may refer to different points in the vehicle coordinate system so that a position detection with the first position detection system and a position detection with the second position detection system may refer to different reference points. The different position detection systems can also be referred to as vehicle location systems.

The vehicle locations may be the whereabouts of the vehicle or points along a vehicle trajectory that has been trawled or driven off.

A core idea of the invention can be seen in that the necessary for a coordinate transformation between two coordinate system control points, that is points whose coordinates are known in both coordinate systems, can be automatically determined by position determinations with two different position detection systems at different vehicle positions. For this, the positions detected by the systems may even refer to different reference points in a vehicle coordinate system.

An advantageous effect of the invention can be seen in that at least the reference point of the position detection with one of a first and a second position detection system in a vehicle coordinate system need not be known in order to determine the transformation parameters between a first coordinate system and a second coordinate system. In other words, it may not be necessary for the determination of such transformation parameters to measure both position detection systems in a vehicle coordinate system, that is, to define reference points of their position detection. Thus, the reference points or location of at least one of the first and second position detection systems or a position detection sensor in the vehicle coordinate system may be unknown. This is advantageous because it is possible to dispense with a calibration of the position detection systems or an adjustment of position detection sensors in this respect for a derivation of the transformation parameters.

One embodiment includes moving the vehicle from a first vehicle location to a second vehicle location and from the second vehicle location to a third vehicle location, detecting three location vectors of the vehicle in the first coordinate system with the first position detection system at the three different vehicle locations, and detecting three Location vectors of the vehicle in the second coordinate system with the second position detection system at the three different vehicle locations. In this embodiment, the orientations of the vehicle at the second and third vehicle locations are substantially the same and different by substantially 180 degrees for the orientation of the vehicle at the first vehicle location. The embodiment further comprises calculating transformation parameters between the first coordinate system and the second coordinate system based on the three position vectors of the vehicle and the three position vectors of the vehicle. The movement of the vehicle can be automated or carried out by a driver. The three different vehicle locations may be along a trajectory. The respective position vectors can refer to different points, for example points on the side of the trajectory.

The first vehicle location can also be referred to as an initial position or as a first calibration position, wherein the first vehicle location can be chosen arbitrarily. At this location, a corresponding location vector and corresponding orientation of the vehicle can be stored in both coordinate systems. The same values can also be stored in each case when the vehicle is located at the second and third vehicle location. The second and third vehicle location may also be referred to as second and third calibration positions.

For realizing the substantially same orientations of the vehicle at the second and third vehicle locations as well as the orientation of the vehicle at the first vehicle location substantially different thereto, detecting orientations of the vehicle with an orientation detection system at least at the first vehicle location at which be provided at the second vehicle location and at the third vehicle location. The sensed orientations may be used for controlling, controlling and / or checking the current orientations of the vehicle as it moves from one of the vehicle locations to another of the vehicle locations. The orientation detection system may in principle be any known sensor for detecting a spatial orientation in any coordinate system, wherein the orientation detection system may comprise, for example, a rotation rate sensor, an inertial sensor or a compass. Alternatively or additionally, an orientation can also be derived from at least two detected vehicle positions or the vehicle trajectory.

In a further embodiment, the orientations of the vehicle are substantially the same at least at two of the three vehicle locations. The orientations of the vehicle may also be substantially the same at the first, second and third vehicle locations. As with the embodiment in which the orientations of the vehicle at the second and third vehicle locations are substantially the same and the orientation of the vehicle at the first vehicle location is substantially 180 degrees, a translational offset of the vehicle between the three vehicle locations may be realized by the vehicle motions become.

A further embodiment comprises calculating at least two control points in the first coordinate system and the second coordinate system based on the three position vectors of the vehicle and the three position vectors of the vehicle and calculating the transformation parameters between the first coordinate system and the second coordinate system based on the at least two control points on. The control points can be located in the vehicle environment. In addition, the control points may be outside the vehicle trajectory. The two control points can define a first difference vector in the first coordinate system and a second difference vector in the second coordinate system, wherein the difference vectors represent identical vectors in both coordinate systems.

Center points can be calculated as control points, the centers being rotational points with respect to a translational and rotational movement of the vehicle, the vehicle moving in such a way that the orientations of the vehicle at the second and third vehicle locations are substantially the same and for orientation of the vehicle at the second first vehicle location differ by substantially 180 degrees. The rotation of the vehicle may be a rigid body rotation of the vehicle.

A first center M1 as the first control point and a second center M2 as the second control point can be calculated according to formula 1 in the first coordinate system (index R) and the second coordinate system (index G), where r _M1 ^{R is} the location vector of the first center point M1 in the first coordinate system, r _M2 ^R the position vector of the second center point M2 in the first coordinate system, r _M1 ^G the position vector of the first center point M1 in the second coordinate system and r _M2 ^G the location vector of the second center point M2 in the second coordinate system. $$\begin{array}{l}{\text{r}}_{\text{M1}}^{\text{R}}=0.5\left({\text{r}}_{\text{V1}}^{\text{R}}+{\text{r}}_{\text{V2}}^{\text{R}}\right){\text{and r}}_{\text{M2}}^{\text{R}}=0.5\left({\text{r}}_{\text{V1}}^{\text{R}}+{\text{r}}_{\text{V3}}^{\text{R}}\right)\\ {\text{r}}_{\text{M1}}^{\text{G}}=0.5\left({\text{r}}_{\text{A1}}^{\text{G}}+{\text{r}}_{\text{A2}}^{\text{G}}\right){\text{and r}}_{\text{M2}}^{\text{G}}=0.5\left({\text{r}}_{\text{A1}}^{\text{G}}+{\text{r}}_{\text{A3}}^{\text{G}}\right)\end{array}$$

The respective location vector of the center points M1 and M2 in the first coordinate system (Index R ) results according to formula 1 by means of different vector additions in different vector parallelograms of the three position vectors (index V1 . V2 and V3 ) with respect to the vehicle in the first coordinate system, for example a local transponder coordinate system. The location vectors can be determined, for example, by means of a transponder system, in particular by means of an RFID network permanently arranged in the vehicle environment and an RFID recognition device located on the vehicle. Alternatively or additionally, the position vectors can be determined by means of an odometry sensor system present on the vehicle.

The respective location vector of the center points M1 and M2 in the second coordinate system (index G) results according to formula 1 by means of various vector additions in different vector parallelograms of the three position vectors (index A1 . A2 and A3 ) with respect to the vehicle in the second coordinate system, for example a global satellite navigation coordinate system such as a GNSS system, a GPS system or a GALILEO system or any other global satellite navigation system. The position vectors can be calculated, for example, by means of at least one antenna arranged on the vehicle for receiving corresponding satellite navigation signals and an evaluation unit for evaluating the received satellite navigation signals. To increase the accuracy of data from a reference station can be received by radio and taken into account by the evaluation.

Based on the calculated midpoints M1 and M2 In the first coordinate system and in the second coordinate system, a first difference vector Δr _M ^R in the first coordinate system (index R) and a second difference vector Δr _M ^G in the second coordinate system (index G) can be calculated by vector subtraction in the respective vector parallelogram of the two centers according to formula 2. $$\begin{array}{l}\mathrm{\Delta }{\text{r}}_{\text{M}}^{\text{R}}={\text{r}}_{\text{M2}}^{\text{R}}-{\text{r}}_{\text{M1}}^{\text{R}}=0.5\left({\text{r}}_{\text{V1}}^{\text{R}}+{\text{r}}_{\text{V3}}^{\text{R}}\right)-0.5\left({\text{r}}_{\text{V1}}^{\text{R}}+{\text{r}}_{\text{V2}}^{\text{R}}\right)=0.5\left({\text{r}}_{\text{V3}}^{\text{R}}-{\text{r}}_{\text{V2}}^{\text{R}}\right)\\ \mathrm{\Delta }{\text{r}}_{\text{M}}^{\text{G}}={\text{r}}_{\text{M2}}^{\text{G}}-{\text{r}}_{\text{M1}}^{\text{G}}=0.5\left({\text{r}}_{\text{A1}}^{\text{G}}+{\text{r}}_{\text{A3}}^{\text{G}}\right)-0.5\left({\text{r}}_{\text{A1}}^{\text{G}}+{\text{r}}_{\text{A2}}^{\text{G}}\right)=0.5\left({\text{r}}_{\text{A3}}^{\text{G}}-{\text{r}}_{\text{A2}}^{\text{G}}\right)\end{array}$$

As can be seen from formula 2, in the calculation of the difference vectors Δr _M ^R and Δr _M ^G terms with respect to the first vehicle location (index 1 ) cut short. The identical in the first coordinate system and the second coordinate system difference vectors .DELTA.R _M ^R and .DELTA.r _M ^G can therefore also from a translational offset of the vehicle between two vehicle locations, that is from a single vehicle translation, such as a translational movement between the second and the third vehicle location (indices 2 and 3 ).

A further embodiment comprises calculating the transformation parameters between the first coordinate system and the second coordinate system independently of the relative arrangement of the second position detection system to the first position detection system or vice versa on the vehicle. A position detection sensor of the second position detection system may be arranged arbitrarily on the vehicle to a position detection sensor of the first position detection system or vice versa. It is therefore not necessary that such position detection sensors are both measured in a vehicle coordinate system or coordinate known. One or both Position detecting sensors can therefore be detachably mounted on the vehicle. Alternatively or additionally, the vehicle can also be tracked by means of a sensor located outside the vehicle, and thus a position vector with respect to the vehicle can be detected. For example, such a location vector can be determined by means of photogrammetry or tachymetry.

The transformation parameters between the first coordinate system and the second coordinate system may include a rotation angle θ between the ordinates or the abscissas of the two coordinate systems and a translation vector r ^G _GR between the origins of the two coordinate systems, where a scale factor between the two coordinate systems is known or substantially equal to one can be.

The angle of rotation θ as angle between the first coordinate system and the second coordinate system can be calculated according to formula 3 by means of trigonometry, wherein the respective abscissa values (index x) and ordinate values (index y) of the two difference vectors Δr _M ^R and Δr _M ^G are used. In the counter of the cosine term according to formula 3, the scalar product of the difference vectors Δr _M ^R and Δr _M ^G can be calculated and in the denominator of the cosine term, the magnitudes of the difference vectors Δr _M ^R and Δr _M ^{G can be} multiplied. $$\mathrm{\theta \; =}{\text{cos}}^{-1}\left(\frac{\mathrm{\Delta }{\text{r}}_{\text{M}\text{, x}}^{\text{G}}\cdot \mathrm{\Delta }{\text{r}}_{\text{M}\text{, x}}^{\text{R}}\cdot \mathrm{\Delta }{\text{r}}_{\text{M}\text{, y}}^{\text{G}}\cdot \mathrm{\Delta }{\text{r}}_{\text{M}\text{, y}}^{\text{R}}}{\left|\mathrm{\Delta }{\text{r}}_{\text{M}}^{\text{R}}\right|\cdot \left|\mathrm{\Delta }{\text{r}}_{\text{M}}^{\text{G}}\right|}\right)$$

With the rotation angle θ, a corresponding rotation matrix A _R ^G between the first coordinate system (index R) and the second coordinate system (index G) or a rotation matrix A _G ^R between the second coordinate system (index G) and the first coordinate system (index R ) can be calculated with corresponding sinusine mines and / or cosine terms.

The translation vector r ^G _GR as an offset between the origins of the two coordinate systems can be calculated according to formula 4, where the position vectors r _M1 ^G and r _M1 ^{R of} the first center point M1 in both coordinate systems together with the rotation matrix A _R ^G between the first coordinate system and the second coordinate system can be used as calculation quantities. $${\text{r}}_{\text{GR}}^{\text{G}}={\text{r}}_{\text{M1}}^{\text{G}}-{\text{A}}_{\text{R}}^{\text{G}}{\text{r}}_{\text{M1}}^{\text{R}}$$

An unknown location vector of a position detection sensor (index VA) of the second position detection system, for example a relative antenna position of an antenna for receiving satellite navigation signals or an antenna of a transponder system to a vehicle reference point, can be calculated on the basis of the preceding calculations according to formula 5 in the second coordinate system (index G). , For example, a satellite navigation coordinate system or a transponder system, in the first coordinate system (index R) and in the vehicle coordinate system (index V) are calculated. $$\begin{array}{l}{\text{r}}_{\text{VA}}^{\text{G}}={\text{r}}_{\text{A1}}^{\text{G}}-\left({\text{r}}_{\text{GR}}^{\text{G}}+{\text{A}}_{\text{R}}^{\text{G}}\cdot {\text{r}}_{\text{V}1}^{\text{R}}\right)\\ {\text{r}}_{\text{VA}}^{\text{R}}={\text{A}}_{\text{G}}^{\text{R}}\cdot {\text{r}}_{\text{VA}}^{\text{G}}\\ {\text{r}}_{\text{VA}}^{\text{V}}={\text{A}}_{\text{R}}^{\text{V}}\cdot {\text{r}}_{\text{VA}}^{\text{R}}\end{array}$$

For the calculation of the unknown position vector r _VA ^{V of} the position detection sensor (index VA) in the vehicle coordinate system (index V) according to formula 5, a rotation matrix A _R ^V between the first coordinate system and the vehicle coordinate system may be used, which may be known. The rotation matrix A _R ^V can be calculated from a known vehicle angle or a known vehicle orientation of the vehicle in the first coordinate system, whereby the vehicle orientation or the vehicle angle can be determined by means of a trajectory or individual position vectors of the vehicle system in the transponder coordinate system as the first coordinate system. Alternatively or additionally, the vehicle orientation or the vehicle angle can be determined by means of an odometry system on the vehicle, in particular by means of wheel speeds and steering angles.

Calculating a current position of the vehicle r _V ^R in the first coordinate system corresponding to a transformation from the second coordinate system into the first coordinate system, that is to say calculating a vehicle reference point which may be defined in the vehicle coordinate system of the vehicle may be calculated according to formula 6 with the calculated translation vector r ^G _GR , the calculated rotation matrix AGR and the rotation matrix A _V ^R as an inverse matrix to the calculated rotation matrix A _R ^V and the calculated position vector r _VA ^V and the detected position vector r _A ^G as a second position vector with respect to the vehicle in the second coordinate system. To calculate r _V ^R , the vector of a position detection sensor (index VA), for example an antenna in the first coordinate system, subtracts the vector r _VA ^V as offset between a reference point and the antenna by the vehicle position in the first coordinate system, for example in an RFID System, to receive. $${\text{r}}_{\text{V}}^{\text{R}}={\text{A}}_{\text{G}}^{\text{R}}\cdot \left({\text{r}}_{\text{A}}^{\text{G}}-{\text{r}}_{\text{GR}}^{\text{G}}\right)-{\text{A}}_{\text{V}}^{\text{R}}\cdot {\text{r}}_{\text{VA}}^{\text{V}}$$

A calculation of a current position of the vehicle r _V ^G in the second coordinate system corresponding to a transformation from the second coordinate system into the first coordinate system can take place with correspondingly analogous calculation variables, in particular inverse calculation variables.

An additional option or an alternative to an automated determination of the transformation parameters for calculating a vehicle position may be a manual determination of the transformation parameters, which may be done without knowledge of a position of a position detection sensor. In one step, by means of a manual or other determination, the position of two RFID grid points of a transponder system in the second coordinate system, for example by placing a GNSS system on these grid points, take place. In another step, an offset between a vehicle reference point and the unknown position of the position detection sensor, for example, an antenna position of a GNSS antenna or a transponder antenna can be calculated either from a CAD drawing or by appropriate calculation.

The detected position vectors and / or specific orientations in the coordinate systems can be assigned uncertainties, that is, variances. Such detection or measurement uncertainties can be taken into account in the individual calculation steps according to the formulas by means of variance propagation in order to estimate or determine the uncertainty, that is to say the accuracy, of the transformed vehicle position. In order to increase the accuracies, redundant detections of position vectors or orientations at the individual vehicle locations can be carried out and averaged over a correspondingly long period of time. In addition, further accuracy-increasing redundancy concepts, in particular with regard to a plurality of position detection sensors, can be provided.

Another embodiment comprises detecting the position vectors of the vehicle in the first coordinate system with a transponder system and detecting the second position vectors of the vehicle in the second coordinate system with a satellite navigation system. The transponder system may be an RFID system, and the satellite navigation system may be a GNSS system, which systems may include respective transmitting units and / or receiving units.

Another embodiment comprises detecting position vectors of the vehicle by means of odometry. The position vectors with respect to the vehicle in the first coordinate system can be detected with an odometry system. Alternatively or additionally, also orientations of the vehicle in the first coordinate system can be determined by means of odometry and optional data filtering. By means of an odometer a position of the vehicle can be determined. The vehicle position may have a local position and / or an orientation of the vehicle. For this purpose, data of a vehicle propulsion system, in particular a respective number of wheel revolutions of a vehicle wheel, a chassis, a yaw rate sensor and / or a steering of the vehicle can be evaluated. A relative position of the vehicle can be derived via a path difference, which in turn can be calculated from the number of wheel revolutions between two measurement times and a known wheel circumference. Via a steering angle of a vehicle wheel, the orientation of the vehicle can also be determined. An absolute position can be derived from a known position, the relative position and the steering angle.

A further solution is a control unit which is set up to carry out the method steps of the method for transforming a position of a vehicle or at least one of the embodiments of the method.

Also, one solution is a positioning system for transforming a position of a vehicle between a first coordinate system and a second coordinate system, the positioning system having at least one component of a first position detection system for detecting at least two location vectors with respect to the vehicle in the first coordinate system at at least two different vehicle locations. The positioning system also includes a component of a second position detection system for detecting at least two location vectors with respect to the vehicle in the second coordinate system at the at least two different vehicle locations. Furthermore, the positioning system has a calculation unit for calculating transformation parameters between the first coordinate system and the second coordinate system based on the at least two location vectors with respect to the vehicle in the first coordinate system and the at least two location vectors with respect to the vehicle in the second coordinate system and calculating the position of the vehicle in one of the first coordinate system and the second coordinate system by transforming the position of the vehicle between the first coordinate system and the second coordinate system with the calculated transformation parameters.

A component of a position detection system may be a sensor for directly or indirectly detecting a location vector with respect to the vehicle. The component can also be a corresponding transmitting unit and / or receiving unit for transmitting or receiving measuring signals for detecting the position vector.

The calculation unit may comprise a control unit, a control unit or a computing unit for controlling, regulating or performing calculation steps for moving the vehicle, for position detection with the first or second position detection system or for transformation of a vehicle position between the two coordinate systems or with one or more be connected to such units.

Furthermore, a solution is a vehicle which has a control unit or a positioning system according to already mentioned solutions.

In one embodiment, the vehicle is operable as a self-propelled vehicle. As a self-propelled vehicle, a self-propelled container transport vehicle for automated transport of containers (AGV) may be provided. Such a self-propelled vehicle can drive by means of the transformation between two coordinate system in areas where only a position detection with one of the two Postionserfassungssysteme is possible. When the vehicle leaves a detection area of the first position detection system, it can resort to the position detection with the second position detection system if it moves into its detection area. The range of action of a self-propelled vehicle can be increased so that the movement of the vehicle can be completely controlled by the transformation.

Hereinafter, associated schematic drawings, which illustrate embodiments in more detail, will be described.

list of figures

• 1 shows a flowchart of method steps of an embodiment of a method for transforming a position of a vehicle between a first coordinate system and a second coordinate system.
• 2 FIG. 12 shows a vehicle at various vehicle locations for illustrating calculation quantities of an embodiment of a method for transforming a position of a vehicle between two coordinate systems shown.
• 3 FIG. 12 shows a vehicle at various vehicle locations to further illustrate the embodiment of the method of transforming a position of a vehicle between the two coordinate systems shown.
• 4 shows a plan view of a vehicle according to an embodiment of the vehicle.

Detailed description of embodiments

In 1 are individual process steps of the method for transforming a position of a vehicle 10 between a first coordinate system 20 a second coordinate system 40 shown in a chronological order.

In one step S0 becomes an orientation 28 of the vehicle 10 at a first vehicle location 12 detected. In a next step S1 becomes a first position vector 22 in a first coordinate system 20 detected. In a further step S2 becomes a first position vector 42 in a second coordinate system 40 detected. The steps S1 and S2 can be performed sequentially or at the same time. In a subsequent step S3 becomes the vehicle 10 to a second vehicle location 14 moves and the steps S0 . S1 and S2 will be executed again.

In a repeated step S0 becomes an orientation 28 of the vehicle 10 at the second vehicle location 14 detected. In a repeated step S1 becomes a second position vector 24 in the first coordinate system 20 detected. In a repeated step S2 becomes a second position vector 44 in the second coordinate system 40 detected. In a repeated subsequent step S3 becomes the vehicle 10 to a third vehicle location 16 moves and the steps S0 . S1 and S2 will be executed again.

In a repeated step S0 becomes an orientation 28 of the vehicle 10 at the third vehicle location 16 detected. In a repeated step S1 becomes a third location vector 26 in the first coordinate system 20 detected. In a repeated step S2 becomes a third location vector 46 in the second coordinate system 40 detected.

Orientation acquisition according to step S0 , the position detection in the first coordinate system 20 according to step S1 and the position detection in the second coordinate system 40 according to step S2 takes place in a rest position or in movement of the vehicle 10 ,

In one of the repeated steps S0 to S3 subsequent step S4 become two control points 62 . 64 based on the position detections in the first coordinate system 20 and in the second coordinate system 40 calculated, with the control points 62 . 64 Rotation points with respect to a movement of the vehicle 10 from the first vehicle location 12 to the second vehicle location 14 and from the first vehicle location 10 to the third vehicle location 16 are.

In one step S4 following step S5 are transformation parameters between the first coordinate system 20 and the second coordinate system 40 calculated which respect 2 be explained in more detail.

In one step S5 following step S6 becomes a vehicle position of the vehicle 10 from the first coordinate system 20 in the second coordinate system 40 or vice versa transformed.

In 2 is the vehicle 10 at different vehicle locations with different orientations 28 shown. In addition, the first coordinate system 20 (Index R) and the second coordinate system 40 (Index G) shown schematically.

The first coordinate system 20 has an abscissa x ^R and an ordinate y ^R , which is a two-dimensional Cartesian coordinate system. The second coordinate system 40 has an abscissa x ^G and an ordinate y ^G , which is also a two-dimensional Cartesian coordinate system in this coordinate system.

The transformation parameters include a translation vector 2 and a rotation angle 4 where a scale factor (not shown) may equal one. The translation vector 2 is as a vector r _GR shown, wherein the translation vector 2 the location vector of origin P _R of the first coordinate system 20 in the second coordinate system 40 is. The translation vector 2 is thus the vector of the origin P _G of the second coordinate system 40 to the origin P _R of the first coordinate system 20 , The rotation angle 4 is shown as angle Θ, where the rotation angle 4 the angle between the ordinates y ^R and y ^G or an angle between the abscissas x ^R and x ^G is.

On the vehicle 10 is a first reference point 6 a first position detection sensor (not shown) for detecting position vectors 22 . 24 . 26 with respect to the vehicle 10 in the first coordinate system 20 at the different vehicle locations 12 . 14 . 16 shown. The reference point 6 is the origin of a vehicle coordinate system 18 , which is a Cartesian coordinate system. The vehicle coordinate system 18 (Index V) has an abscissa x ^V and an ordinate y ^V where the abscissa x ^V in the vehicle longitudinal direction and the ordinate y ^V is aligned in the vehicle transverse direction.

A transformed position of the vehicle 10 is in the first coordinate system 20 with respect to the reference point 6 indicated and is with the vector r _RV shown. A transformed position of the vehicle 10 becomes in second coordinate system 40 also with respect to the reference point 6 indicated and is with the vector r _GV shown.

On the vehicle 10 is also a second reference point 8th a second position detection sensor (not shown) for detecting position vectors 42 . 44 . 46 with respect to the vehicle 10 in the second coordinate system 40 at the different vehicle locations 12 . 14 . 16 shown.

The orientations 28 of the vehicle 10 are as the vehicle angle φ between the abscissa x ^V of the vehicle coordinate system 18 and the abscissa x ^R of the first coordinate system 20 shown. Alternatively, a shown angle φ as a vehicle angle between an orientation or reference direction of the second position detection sensor and the abscissa may also be used x ^G of the second coordinate system 40 be used.

In 3 are the coordinate systems 20 . 40 out 2 and the vehicle 10 with its vehicle coordinate system 18 shown again.

In the first coordinate system 20 are the endpoints of a first place vector 22 , a second location vector 24 and a third location vector 26 on the vehicle 10 without the respective vectors shown. The endpoints of the position vectors 22 . 24 . 26 in the first coordinate system 20 can the reference points 6 in 2 correspond and in the respective origins of the vehicle coordinate system 18 lie at the different vehicle locations.

In the second coordinate system 40 are the endpoints of a first place vector 42 , a second location vector 44 and a third location vector 46 on the vehicle 10 without the respective vectors shown. The location vectors 42 . 44 . 46 in the first coordinate system 20 can the reference points 8th in 2 correspond to a position of a position detection sensor of the second position detection system on the vehicle 10 Respectively.

The vehicle 10 moves on a vehicle trajectory 11 from the first vehicle location 12 to the second vehicle location 14 and then to the third vehicle location 16 , where the vehicle 10 from the first vehicle location 12 to the second vehicle location 14 moves with a translatory and rotating motion and thereby to the first control point 62 , which as the center M1 the rotating vehicle movement is shown rotating. The vehicle 10 describes a rotation of about 180 degrees. The vehicle 10 continues from the second vehicle location 14 to the third vehicle location 16 with a translational and, as a result, substantially non-rotating motion between the second and third vehicle locations 14 . 16 , where the vehicle is around the second control point 64 , which as the center M2 the rotating vehicle movement with respect to the first vehicle location 12 is shown, further with respect to the first vehicle location 12 rotates.

The first control point 62 as the center M1 shown results geometrically from a straight line section of a first straight line between the end points of the first locus vector 22 and the second location vector 24 in the first coordinate system 20 and a second line between the endpoints of the first location vector 42 and the second location vector 44 in the second coordinate system 40 ,

The second control point 64 as the center M2 shown results geometrically from a straight line section of a first straight line between the end points of the first locus vector 22 and the third location vector 26 in the first coordinate system 20 and a second line between the endpoints of the first location vector 42 and the third location vector 46 in the second coordinate system 40 ,

Based on the two control points 62 . 64 or a difference vector 66 between the control points 62 . 64 as identical elements in both coordinate systems 20 . 40 can then use the transformation parameters 2 . 4 be calculated.

In 4 is the vehicle 10 schematically shown, wherein components of a positioning system 80 are shown. The positioning system 80 has a component 82 the first position detection system for detecting the position vectors 22 . 24 . 26 in the first coordinate system 20 on. The positioning system 80 also has a component 84 the second position detection system for detecting the position vectors 42 . 44 . 46 in the second coordinate system 40 on. The component 82 of the first position detection system may be an antenna (not shown) of a transponder antenna system and the component 84 of the second position detection system may be an antenna (not shown) of a GNSS system. The components 82 . 84 are arranged at different locations on the vehicle.

The vehicle 10 also has a calculation unit 86 to calculate the transformation parameters 2 . 4 and a controller 90 for performing the method steps S0 to S6 on.

The component 82 of the first position detection system is connected to the calculation unit 86 and with the controller 90 connected for data communication and for communicating control commands. The component 84 of the second position detection system is also connected to the calculation unit 86 and with the controller 90 connected for data communication and for communicating control commands. Further, the calculation unit 86 connected to the controller for these purposes.

LIST OF REFERENCE NUMBERS

2

translation vector

4

rotation angle

6

first point of reference

8th

second reference point

10

vehicle

11

vehicle trajectory

12

first vehicle location

14

second vehicle location

16

third vehicle location

18

Vehicle coordinate system

20

first coordinate system

22

first position vector in the first coordinate system

24

second position vector in the first coordinate system

26

third position vector in the first coordinate system

28

Orientation in the first coordinate system

40

second coordinate system

42

first position vector in the second coordinate system

44

second position vector in the second coordinate system

46

third position vector in the second coordinate system

62

first control point

64

second control point

66

difference vector

80

positioning system

82

Component of the first position detection system

84

Component of the second position detection system

86

calculation unit

90

control unit

S0

orientation detection

S1

Position detection in the first coordinate system

S2

Position detection in the second coordinate system

S3

vehicle movement

S4

Control point calculation

S5

Calculation transformation parameters

S6

Transformation vehicle position

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102016108446 A1 [0002]

Claims (11)

A method of transforming a position of a vehicle (10) between a first coordinate system (20) and a second coordinate system (40), comprising the steps of detecting (S1) at least two location vectors (22, 24, 26) with respect to the vehicle (10) the first coordinate system (20) having a first position detection system at at least two different vehicle locations (12, 14, 16), characterized by detecting (S2) at least two location vectors (42, 44, 46) relative to the vehicle (10) in the second coordinate system (40) having a second position detection system at the at least two different vehicle locations (12, 14, 16), calculating (S5) transformation parameters between the first coordinate system (20) and the second coordinate system (40) based on the at least two location vectors (22, 24, 26) in the first coordinate system (20) and the at least two location vectors (42, 44, 46) in the second coordinate system (40) and calculating (S6) the position of the vehicle (10) in one of the first coordinate system (20) and the second coordinate system (40) by transforming the position of the vehicle (10) between the first coordinate system (20) and the second coordinate system (40) with the calculated transformation parameters , Method according to Claim 1 characterized by moving (S3) the vehicle (10) from a first vehicle location (12) to a second vehicle location (14) and from the second vehicle location (14) to a third vehicle location (16), detecting (S1) three location vectors ( 22, 24, 26) of the vehicle (10) in the first coordinate system (20) with the first position detection system at the three different vehicle locations (12, 14, 16), detecting (S2) three position vectors (42, 44, 46) of the Vehicle (10) in the second coordinate system (40) with the second position detection system at the three different vehicle locations (12, 14, 16), wherein the orientations (28) of the vehicle (10) at the second and third vehicle locations (14, 16) are substantially the same and different for orientation (28) of the vehicle (10) at the first vehicle location (12) by substantially 180 degrees, and calculating (S5) transformation parameters between the first coordinate system (20) and the second coordinate system (40 ) based on the three Or tsvektoren (22, 24, 26) of the vehicle (10) and the three position vectors (42, 44, 46) of the vehicle (10). Method according to Claim 2 characterized in that the orientations (28) of the vehicle (10) are substantially equal at least at two of the three vehicle locations (12, 14, 16). Method according to one of Claims 2 or 3 Characterized by calculating (S4) of at least two control points (62, 64) in the first coordinate system (20) and the second coordinate system (40) based on the three position vectors (22, 24, 26) of the vehicle (10) and the three Location vectors (42, 44, 46) of the vehicle (10) and calculating (S5) the transformation parameters between the first coordinate system (20) and the second coordinate system (40) based on the at least two control points (62, 64). Method according to one of the preceding claims, characterized by calculating (S5) the transformation parameters between the first coordinate system (20) and the second coordinate system (40) independently of the relative arrangement of the second position detection system to the first position detection system on the vehicle (10). Method according to one of the preceding claims, characterized by detecting (S1) the position vectors (22, 24, 26) of the vehicle (10) in the first coordinate system (20) with a transponder system and detecting (S2) the position vectors (42, 44, 46 ) of the vehicle (10) in the second coordinate system (40) with a satellite navigation system. Method according to one of the preceding claims, characterized by detecting (S1) position vectors (22, 24, 26) of the vehicle (10) by means of odometry. Control device (90) which is adapted to perform the method steps according to one of the preceding claims. A positioning system (80) for transforming a position of a vehicle (10) between a first coordinate system (20) and a second coordinate system (40), comprising at least one component of a first position detection system (82) for detecting at least two location vectors (22, 24, 26 ) with respect to the vehicle (10) in the first coordinate system (20) at at least two different vehicle locations (12, 14, 16), characterized by at least one component of a second position detection system (84) for detecting at least two location vectors (42, 44, 46 ) with respect to the vehicle (10) in the second coordinate system (40) at the at least two different vehicle locations (12, 14, 16) and a calculation unit (86) for calculating transformation parameters between the first coordinate system (20) and the second coordinate system (40 ) based on the at least two location vectors (22, 24, 26) relative to the vehicle (10) in the first coordinate system (2 0) and the at least two location vectors (42, 44, 46) relative to the vehicle (10) in the second coordinate system (40) and for calculating the position of the vehicle (10) in one of the first coordinate system (20) and the second coordinate system (40) by transforming the position of the vehicle (10) between the first coordinate system (20) and the second coordinate system (40) with the calculated transformation parameters. Vehicle (10), which a control unit (90) according to Claim 8 or a positioning system (80) Claim 9 having. Vehicle (10) to Claim 10 wherein the vehicle (10) is operable as a self-propelled vehicle.

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