DE102006004400A1 - Navigation system, device and navigation method - Google Patents

Abstract

The navigation system has a matrix-shaped network of placemarks, which indicate a spatial position, and a navigation unit. The navigation unit has a reading device for reading the positions indicated by means of the placemarks, an alignment measuring device for determining the alignment and a computing unit for calculating driving information from the information read out and the alignment.

Description

The The invention relates to a navigation system, a device and a Navigation procedures.

Robot, as used for example in warehousing, industrial robots and cleaning robots need be able to orient oneself in their environment to the way of one given starting point to find a given endpoint.

A Possibility, a robot's navigation in space, e.g. a room or one Hall to enable is to provide the room with orientation marks, so that the robot can orientate on the basis of these orientation marks.

For example The alignment can be visually arranged by means of a robot Camera be realized, or by detecting the earth's magnetic field or an artificial one Magnetic field. Furthermore, could The robot is oriented to an electric field.

A another possibility is to equip the room on the floor with transponders, so that the robot can read out position data when using it Transponder passes, and can determine its own direction of travel. For example, can this space be designed with tiles that have transponders.

The Navigation of robots arranged in the ground for orientation Using transponders, however, is characterized by a problem. Of the Direction vector of the robot and the orientation, i. the alignment, of the transponder system, i. a coordinate system that consists of a Plurality of transponders is built up, in the ground are uncorrelated. A balance that needed is to allow the robot to move along the coordinate axes of the Transponder formed coordinate system moves, can only by Evaluation of many consecutive tags done. That can lead to vibration tendency of the control system of robot navigation. Just in small rooms does this to unsatisfactory results in navigation.

Around to solve this problem, Upgrading is done so far, if at all, across many transponders. To do this many transponders are read out. The information will be in the direction determination included and a direction vector of the movement of the robot, i. the course of the robot is appreciated. ever more transponders are read, the more accurate the vector can be be determined, but in this case by the robot a size Distance covered must be to read out the appropriate number of transponders to be able to. A close-meshed network of transponders is often not possible because with the number of transponders also the costs for the transponder network climb.

Of the Invention is based on the problem, a reliable and cost-effective Navigation system for To create robots that have a position and orientation determination allowed and allowed a ride of the robot to a given destination.

The Problem is caused by a navigation system, a device and a Navigation method with the features solved according to the independent claims.

One Navigation system has a matrix-shaped network of placemarks, the one spatial Specify position and a navigation unit. Hereby points The navigation unit is a reader for reading by means of Placemarks specified positions, an alignment measuring device for determining the orientation, and a calculating unit for calculating of driving information from the information read and the Focus on.

A Device has a motor and steering device, a navigation unit of the navigation system, and a transportation control unit on, with the engine and Steering of the means of locomotion control unit by means of the Navigation unit calculated driving information is controlled.

One Navigation method, comprises the steps of detecting a placemark, Reading the information given by the placemark, determining the spatial Alignment, and calculating a directional information to a given Position to, up.

clear An aspect of the invention can be seen in that for a navigation system, the a network of placemarks and a navigation unit, with whose help is the movement of a robot to a given destination to be controlled, the calculation of the necessary direction is accelerated by the orientation of the robot from a Alignment measuring device is made. For example, can the local market network consist of a plurality of radio transponders, arranged in a matrix are, with the location information of the radio transponder read when the robot with the navigation unit mounted thereon over the Radio transponder is driving, and wherein the orientation of the robot is detected by means of a compass becomes. Thus, the current position from the detection of one of the transponder be determined and the orientation of the robot can be parallel be determined by means of the compass. Therefore, the information which are necessary for defining a "course" of the robot, Completely available as soon as the robot with the navigation system mounted on it a single placemark is driven.

Generally Placemarks are set up so that they by means of optical (e.g., markings on walls and / or on the floor and / or on the ceiling), acoustic (e.g. Ultrasound), or electromagnetic devices (e.g., transmitters, which permanently emit an electromagnetic signal) detected can be.

further developments The invention will become apparent from the dependent claims.

According to one Embodiment of the invention, the navigation system, transponder on, which are intended as placemarks. Being a transponder Generally understood devices that respond to a received signal a stored information, for example by means of radio waves radiate.

Especially advantageous in each transponder is a unique identification number stored and the navigation unit has a database, the each identification number the position of the transponder and the orientation regarding assigns a fixed main direction of the transponder network. Consequently can the price for the placemark network can be reduced because these transponders are not even the location information must be able to store and thus simpler transponder can be used Identifiable by means of a unique serial number. in this connection For determining the location information, the serial number of a transponder can be used be read and the location information determined from a database be assigned in each transponder, the location information is. For this it is necessary that after laying the transponder whose position is detected and the position of each transponder linked to the respective serial number.

According to one Embodiment of the invention is the orientation in each transponder of the transponder stored in a fixed main direction of the transponder network, in particular, the fixed main direction is the direction of the North Magnetic's is and the registration measuring device Compass is. Clearly, the advantage of this embodiment in that for a building with a variety of spaces a separate network of transponders installed in each individual room is, these networks neither a defined orientation to own the earth's magnetic field, nor this plurality of networks with each other have defined orientations. Thus, it is important that the Device that applies this navigation unit, the relative Alignment between, for example, the earth's magnetic field, which by means of a Compass is detected, and determine the transponder network can. Thus, greater flexibility of the navigation system be achieved by the device without further configuration in these rooms can be used.

Especially can RFID (radio frequency identification) transponder used, which is a particularly preferred form of radio transponders are. RFID transponder are particularly suitable for the sightless and contactless reading of information. Furthermore, they are inexpensive manufacture. Furthermore can in a simple way, e.g. under or in a rug or in Floor panels are arranged, so a network of placemarks to build.

Especially Preferably, the device is a robot. A robot is general a device that performs a task autonomously. In particular, a robot in this context, a self-propelled device, e.g. to the Carry out cleaning, storage and delivery tasks.

According to one embodiment of the invention, the device has a distance measuring device. The distance measuring device is for measuring the distance traveled by the device. The distance covered can be controlled by the means of locomotion control of the landing gear of the Device are taken into account. For example, a distance to be covered can be monitored by means of the distance measuring device. For example, only that transponder which is arranged at a pre-calculated distance from the transponder at the starting point of the journey is accepted as the destination transponder.

Further allows it the route measuring device, ride information in the form to give instructions such as "straight ahead, 5 meters". Thus, positions are also precise reachable, on which no transponder is arranged. Consequently, can the precision be increased and the susceptibility to errors are reduced.

The above developments of the navigation system and the device, a navigation unit of a corresponding navigation system apply in the same way to the navigation procedure, which is carried out on the navigation unit.

embodiments The invention is illustrated in the figures and will be discussed below explained in more detail.

1 shows a preferred embodiment of the invention.

2 represents an exemplary processor element.

3 schematically shows a robot.

4 shows information for calculating the current driving information for the robot.

The Figures described only serve to explain the invention and provide in particular, not to scale Illustrations of the subject invention.

In all figures are the same or identical where appropriate Components of the figures with the same reference numerals designated.

1 shows an embodiment of the invention.

In 1 is a network of a plurality of processor elements arranged in matrix form 100 shown. There is also a robot 200 represented between these processor elements 100 located. The columns and rows of the matrix in which the processor elements 100 are arranged to define a frame of reference, where the direction of the columns of the "x" direction 110 corresponds to and the direction of the lines of the "y" direction 120 , The x and y directions are oriented perpendicular to each other. As in 1 As shown, the origin of this frame of reference lies in the processor element 100 , this in 1 shown at the top left. The arrow of the x-direction 110 therefore shows in 1 from top to bottom and the arrow of the y-direction 120 shows in 1 from left to right with increasing values. Thus, a reference system is created with which each point of a two-dimensional space can be unambiguously designated by means of a corresponding coordinate specification (x, y).

In one embodiment of the invention, the processor elements are 100 arranged in a hall or a room on the floor. The position of obstacles and targets for the robot 200 can be accurately identified using this coordinate system. Typically, there is the task of a robot 200 in driving from a starting point to an object, eg a pallet, picking up the pallet and then driving the pallet to an end point and stopping the pallet there. The robot should move in a predetermined way, so as not to collide with obstacles. Another task of the robot 200 could be to carry out autonomous cleaning work on the ground, whereby predetermined areas may not be traveled. These "forbidden" areas are identified by means of corresponding coordinates.

As in 1 shown, the robot points 200 opposite that through the network of processor elements 100 predetermined coordinate system to an initial orientation, which is generally unknown, and by the angle α 130 , which is called the orientation angle, is shown. That is, the orientation axis of the robot 200 indicates the orientation angle α with respect to a reference axis of the network 130 on. Exemplary is in 1 the x-axis 110 of the network selected as the reference axis. The orientation angle α 130 can also be understood as the "course" of the robot 200 be designated in In this example, 0 ° is when the robot moves up, 90 ° when it goes to the right, 180 ° when it goes down, and 270 ° when it goes to the left.

2 represents an exemplary processor element.

As in 2 shows a processor element 100 that exemplifies the in 1 shown processor elements is a control unit 101 , a storage device 102 and an antenna 103 on, which are arranged on a substrate. The processor element 100 may further comprise a battery, not shown.

The control unit 101 may be a microcontroller or the like, and is for controlling the processor element 100 set up. In particular, the control unit reads 101 from the storage device 102 Information and gives it by means of the antenna 103 off, if by means of the antenna 103 a read signal from the robot 200 Will be received.

Particularly advantageous is the processor element 100 an RFID transponder, wherein the energy for reading out and outputting the information stored in the transponder from the read signal of the robot 200 is won.

The storage device 102 has location coordinates of the processor element 100 on. The location coordinates of the processor element 100 can x and y coordinates with respect to in 1 and the number of the space in which the processor element network is arranged so that the position of each processor element 100 is clearly identified. The number of the room may include information about the floor and / or the building. Thus it is achieved that a robot 200 also on the entire surface of a large area with several buildings, each of which has several floors with several rooms, can orient. Alternatively, in the storage device 102 an individual serial number of the respective processor element 100 stored, wherein a database is provided, which by means of the serial number each processor element 100 assigns the exact position. To create the database in this case must be the serial number of each processor element 100 once after the laying of the processor elements are read out and the serial number of the position of the corresponding processor element 100 stored in a database. Upon a write process after laying the processor elements to store the location coordinates in the processor elements 100 can therefore be dispensed with.

3 schematically shows a robot.

The robot 200 has a motor and steering device 210 and a navigation unit 250 on, with the engine and steering device 210 is set up to move the robot on a predeterminable path. Clearly allows the engine and steering device 210 the forward and reverse drive of the robot 200 and a turning of the robot 200 so the robot 200 can be moved to a predetermined destination point.

The navigation unit 250 allows orientation of the robot 200 in the room and controls the engine and steering device 210 according to reaching a predetermined destination.

The navigation unit 250 has a receiving and transmitting device 251 , an alignment measuring device 252 , a computing unit 253 and a control unit 254 on.

The receiving and transmitting device 251 is used to read out information contained in the processor elements 100 are stored, set up. In particular, there is the receiving and transmitting device 251 essentially an antenna for transmitting a read signal and receiving it from the processor element 100 sent out information.

The alignment measuring device 252 serves to detect the orientation of the robot 200 ie for measuring the orientation angle α 130 or the course of the robot 200 with respect to a given main direction of the frame of reference. The alignment measuring device 252 may be a compass, the main direction of the reference system being the direction of the magnetic north pole. Alternatively, a reference system can also be generated by artificial electrical, electromagnetic or magnetic fields or by sound waves, such as ultrasound, wherein the alignment measuring device 252 having corresponding sensors. Alternatively, optically detectable symbols can be placed on the floor or on the walls be net, with the alignment measuring device 252 an optical sensor, that has a camera. Clearly, this system is comparable to known radio beacons.

The arithmetic unit 253 has a microprocessor and possibly an unillustrated storage element. The arithmetic unit 253 is with the receiving and transmitting device 251 coupled and receives the from the receiving and transmitting device 251 read information of the transponder, ie the processor elements 100 , Furthermore, the arithmetic unit 253 with the alignment measuring device 252 coupled to the orientation angle α 130 to recieve. From the measured orientation angle α 130 of the robot 200 and the location coordinates of the processor element 100 while driving the robot 200 over the processor element 100 by means of the receiving and transmitting device 251 be read out, calculates the arithmetic unit 253 the course that the robot 200 has to drive to a predetermined destination.

In general, however, the robot will not be able to drive the direct straight path to the destination because there are obstacles along the way. In this case, the arithmetic unit calculates 253 a path which lies within a predetermined corridor, ie which is oriented at predetermined routes in space. From the known location coordinates of the starting point and the destination point, the arithmetic unit 253 furthermore calculate the distance to be covered, which can serve as a control of the distance traveled.

The arithmetic unit 253 is also with the control unit 254 coupled, and outputs information about the calculated path to this.

The control unit 254 receives the from the arithmetic unit 253 calculated path information and controls the engine and steering device 210 so that the robot 200 follows the calculated path and thus reaches the destination point in this way.

Furthermore, the arithmetic unit 253 with a distance measuring device 220 coupled to that of the robot 200 measures the distance traveled. This allows the arithmetic unit 253 determine if the target point has been reached.

This information serves on the one hand to control the position of the robot 200 , in which case the robot 200 from processor element 100 to processor element 100 moves and after a previously calculated distance a predetermined processor element 100 is not reached, an error is detected. If an error is detected, an alarm can be issued, the robot 200 stop or automatically recalibrate the current position and orientation as described below.

On the other hand, a previously calculated distance allows the precise control of the target point by the robot 200 even if at this point no processor element 100 is arranged. This ensures that the network of processor elements 100 can have a large mesh spacing, which is the number of processor elements 100 reduced on a given area and reduced costs.

According to the navigation method, in a first step, when the current position of the robot 200 generally still unknown, the robot 200 controlled accordingly to go straight until a transponder signal of a transponder 100 is detected. During operation of the robot 200 is from the robot, ie the receiving and transmitting device 251 , permanently sent out a read signal. If the robot 200 In response to a read signal, a transponder signal is received from the transponder signal in the transponder 100 stored information is read out. As with reference to 2 is explained, this information contains location information of the transponder 100 , or the location information can from the information read by means of a in the navigation unit 250 prestored database. This location information also corresponds to the current position of the robot 200 , In addition, by means of the alignment measuring device 252 , eg the compass, the orientation of the robot 200 certainly. From the known current location and orientation information are from the arithmetic unit 253 current driving information for the robot 200 calculated. By means of the control unit 254 can the robot 200 be controlled so that the robot 200 moved to a given destination.

Based on 4 Calculation steps for calculating the current driving information for the robot are explained.

4 shows the general case that the reference system defined by the transponder network is not in the main direction 300 matches. This is particularly relevant if a plurality of transponder networks are arranged in different rooms of a building and as the main direction 300 in each case the direction of the magnetic north pole is used. Furthermore, when laying the processor elements 100 the direction of the magnetic north pole are not taken into account, which simplifies the laying.

Therefore, a transponder network similar to the one in 1 shown corresponds, shown rotated. For example, in 1 the angle between the axis 300 in the direction of the magnetic north pole, which defines an angle of 0 °, and the x-axis 110 of the reference system of the transponder network about 45 °. The origin of this reference system lies in the uppermost transponder 100a the transponder network, so that this transponder 100a the coordinates (0,0). This transponder 100a is referred to as the source processor element. Coordinates are represented in the notation (x-intercept, y-intercept). The robot 200 is located at a starting point with the transponder 100b matches in 5 shown at the bottom. The coordinates of this transponder 100b , ie the starting coordinates, are (2,2). The transponder 100b is called a start point processor element. The destination point has the coordinates (0,1). Likewise, the target point is at the target point processor element 100c , The initial orientation of the robot, using the robot alignment angle 301 is 90 °, ie the robot is turned to the right.

The course 302 ie the target orientation of the robot, which is in line with the target point processor element 100c leads is from the arithmetic unit 253 calculated by Course = alignment of the frame of reference - direction of the target point, in which
the orientation of the reference frame, the angle between the axis of the main direction 300 and the x-direction 110 of the transponder network, and
the direction of the target point 100c , the angle between the x-direction 110 of the transponder network and the direction of the connecting line 303 between the starting point 100b and the destination point 100c indicates.

y_Start, y_Ziel, x_Start und x_Ziel bezeichnen jeweils die x- bzw. y-Komponenten des Startpunkts 100b und des Zielpunkts 100c.In particular, therefore, in this example:

y _start , y _destination , x _start, and x _destination denote the x and y components of the starting point, respectively 100b and the destination 100c ,

In the example, this results in a course 302 of 28 °, or the robot 200 must rotate 62 ° (90 ° -28 °) counterclockwise to the target point 100c In this example, it is assumed that the distances between adjacent processor elements of a column and adjacent processor elements of a row of the matrix of processor elements are the same.

The distance to the destination point 100c can be easily calculated here with the theorem of Pythagoras, resulting in a distance of √5 × length unit to be covered. The length unit corresponds to the distance between two adjacent transponder elements 100 ,

This calculation is done while the robot is moving 200 repeatedly performed. For example, the calculation is performed for each subsection of the path to the destination when the robot 200 can not move there in a straight way. Alternatively, only the path from one processor element is ever made 200 to the adjacent processor element 200 calculated until the destination point 100c is reached.

It is therefore a particular advantage of this navigation system for robots that a position and orientation of the robot can be determined as soon as a single transponder signal has been received by the navigation unit and the location coordinates of the corresponding transponder can be read out since the alignment of the robot by means of a compass is determinable. As a result, the denser the network of transponders, the faster and more accurate positioning 100 is arranged. However, since the cost of this network with the number of transponders 100 a compromise has to be made which is in line with the application.

The robot 200 It is also set up that it initially, if the exact location of the transponder 200 is not known, self-calibrated, ie the navigation unit 250 of the robot 200 performs a given procedure to determine the current position. The calibration procedure may also be performed during operation if a deviation is determined from a comparison of the distance traveled and a current position expected from the calculation, as explained above.

Such a calibration procedure is necessary because the antenna 251 the navigation unit 250 receives the transponder signal in a range of up to half a meter. An inadequate calibration therefore causes the robot 200 with an appropriate distance from the processor elements 100 moved parallel to the calculated path and thus does not reach the target point precisely.

According to one embodiment, the robot may travel along a predetermined path and continuously measure the intensity of a received transponder signal to determine the point of greatest intensity that corresponds to the exact position of the transponder element. For this purpose, the antenna 251 for determining the intensity of the received transponder signal. For example, the robot 200 driving on a spiral path, or on a zigzag path.

100

processor element

100a

Originating processor element

100b

Starting point processor element

100c

Destination processor element

101

control unit

102

storage device

103

antenna

110

x-direction

120

y-direction

130

Alignment angle α

200

robot

210

Engine- and steering device

220

Travel distance measuring device

250

navigation unit

251

reception and transmitting device

252

compass

253

computer unit

254

control unit

300

main direction

301

Robot orientation angle

302

course

Claims (12)

Navigation system, comprising: • a matrix-like network of placemarks ( 100 ) indicating a spatial position; and • a navigation unit ( 250 ) with - a receiving and transmitting device ( 251 ) for reading by means of placemarks ( 100 ) specified positions; An alignment measuring device ( 252 ) for determining the orientation; and a computing unit ( 253 ) for calculating driving information from the read-out information and the orientation. Navigation system according to claim 1, wherein as local marks ( 100 ) Transponders are provided. Navigation system according to claim 2, wherein in each transponder ( 100 ) a unique identification number is stored, and the navigation unit ( 250 ) has a database containing each identification number the position of the transponder ( 100 ) and the alignment with respect to a fixed main direction ( 300 ) of the transponder network. Navigation system according to one of claims 2 or 3, wherein in each transponder ( 100 ) the posi tion of the transponder ( 100 ) and the alignment with respect to a fixed main direction ( 300 ) of the transponder network is stored. Navigation system according to one of claims 3 or 4, wherein the fixed main direction ( 300 ) is the direction of the magnetic north pole and the alignment measuring device ( 252 ) is a compass. Navigation system according to one of claims 2 to 5, wherein the transponders ( 100 ) RFID transponders are. Device with • a motor and steering device ( 210 ), • a navigation unit ( 250 ) of a navigation system according to one of claims 1 to 7, and • a means of locomotion control ( 220 ), wherein the engine and steering device ( 210 ) from the means of locomotion control ( 254 ) by means of the navigation unit ( 250 ) calculated driving information is controlled. Device according to claim 7, wherein the device is a robot. Device according to claim 7 or 8, comprising a distance measuring device ( 220 ) having. Navigation method, with the steps: • Detect a placemark; • Readout the information given by the placemark; • Determine the spatial orientation; and • To calculate a direction information to a predetermined position. Method according to claim 10, with the steps: Detect the alignment of the placemark in terms of a fixed main direction; and Update the direction information based on the orientation of the transponder. Method according to claim 10 or 11, with a distance measured between two positions becomes.