A ground vehicle configured to transport a load and operate without a driver for autonomous movement

Abstract

The present invention relates to a ground transportation vehicle (1) configured for driverless autonomous operation, which is for a load (2) to be transported and comprises at least: a control system (3) that controls and maneuvers the ground transportation vehicle (1); an evaluation unit (4) that generates a signal for stopping the ground transportation vehicle (1), wherein a detection device (5) for identifying persons and / or objects located in the travel path is connected to the control system (3), wherein the control system (3) is configured to check a protection zone (24) and / or an alarm zone (25) of the detection device (5), and wherein the protection zone (24) and / or the alarm zone (25) can be automatically switched according to the position of the ground transportation vehicle (1) and / or an obstacle detected in the travel path of the ground transportation vehicle (1).

Description

Technical Field

[0001] The present invention relates to a ground transportation vehicle (Automated Guided Vehicle, AGV) for a load to be transported, which is configured for driverless autonomous operation. The present invention is particularly applicable to robotic transportation vehicles for transporting loads. It also includes lift-type ground transportation vehicles, non-stacking lift trucks, and corresponding combinations. Background Art

[0002] With the progress of automation technology, the operation of loads becomes increasingly important.

[0003] In practice, most attempts are made to prevent collisions with personnel by using a laser scanner with a PLrd (Performance Level according to ISO 13849-1:2006).

[0004] In order to unload the transported goods, it drives into a so-called "supermarket" (placement or storage area), where the laser scanner is turned off in order to approach the unloading position, which results in the fact that during the drive-in, the transported goods already present in the supermarket cannot be recognized or can only be recognized with insufficient safety. Therefore, the supermarket is regarded as a dangerous area that can only be entered by authorized personnel. These personnel are usually alerted by a flashing light and an acoustic signal when the AGV drives into the dangerous area. In addition, the personnel trapped in the dangerous area can mostly stop the AGV by means of an emergency stop button. Some AGVs have to unload the transported goods at a certain safety distance relative to each other, which results in an increased space requirement. It is also known to regard the drive-in area as a dangerous area and thus block it as a footpath. Summary of the Invention

[0005] Starting from this, the object of the present invention is to provide a ground transportation vehicle for a load to be transported, which is configured for driverless autonomous operation, and which alleviates or even avoids the above-mentioned disadvantages. In particular, it should be possible to improve personnel protection when unloading transported goods in a dangerous area, eliminate additional emergency stop buttons, and / or reduce space requirements in a structurally simple manner. Another objective can be to safely drive over a footpath when driving into a dangerous area, while safely preventing the laser scanner from being turned off or prematurely switching to a narrow protection area with a PLd.

[0006] These tasks are solved by a ground transportation vehicle according to the present invention. Other design solutions of the present invention are given in other parts of the present disclosure. It should be noted that other details and improvement solutions for implementing the present invention are especially described in conjunction with the drawings, and these details and improvement solutions can be combined with the features in the claims.

[0007] The following ground vehicle helps with this. The ground vehicle is set up for driverless autonomous operation, is for a load to be transported and at least comprises:

[0008] - A control system which controls and manoeuvres the ground vehicle,

[0009] - An assessment unit which generates a signal for stopping the ground vehicle, wherein a detection device for identifying persons and / or objects located in the travel path is connected to the control system, wherein the control system is set up to check the protection zone and / or warning zone of the detection device, and wherein the protection zone and / or warning zone can be automatically switched depending on the position of the ground vehicle and / or an obstacle detected in the travel path of the ground vehicle.

[0010] The ground vehicle proposed here has the advantage that after an obstacle in a supermarket has been identified by a rearward-facing laser scanner (by means of the warning zone), activating a narrower protection zone enables identification of a person who has become trapped. The AGV stops without contact and no additional emergency stop button is required. In normal operation (without a trapped person), the narrower protection zone "observes" under the goods conveyor support (sliding gantry, dolly) on which the loaded goods conveyor is placed, optimally utilising the space in the "supermarket aisle". By safely monitored wheel odometry, it is ensured that the switch to the narrow protection zone only occurs in a hazardous area. That is to say, the laser scanner zone required for safely crossing a footpath is selected before starting to drive backwards and is compulsorily maintained on the predefined travel path.

[0011] The driverless ground vehicle can be a power-driven vehicle determined for active travel and, if necessary, includes any trailers. For this purpose, the ground vehicle can cooperate with a guidance system for a predefined travel route in the ground or in the surrounding environment.

[0012] "Load" means an object to be operated, including its mass, dimensions, state and / or arrangement. The load can (only) consist of the loaded goods. The load can also include the loaded goods and a conveying device for the loaded goods, such as a conveyor cart, a pallet, a hand truck (Bodenroller), etc. "Load operation" which can be carried out by the ground vehicle is understood in particular as lifting, lowering, load transfer and / or load handling.

[0013] The control system has the following automatic devices as its contents, which control (e.g., activate / deactivate) and manipulate (monitored by sensors if necessary) the ground vehicle and its associated devices. The system of a driverless ground vehicle includes the following control system, which can be part of the ground vehicle and / or separate from it. The control system can include the following computing unit, which is arranged in or on the ground vehicle.

[0014] The evaluation unit can be preferably conductively and data-conductively connected to the sensor system (e.g., detection device) and is arranged for processing its signals. The evaluation unit is in particular arranged for analyzing the data of the sensor system or the detection device, so that the person, object, or body (in the area behind the ground vehicle) can be clearly detected or determined with respect to its orientation / position. The orientation determined in the evaluation unit can be adjusted or influenced using predefined (e.g., stored and / or set) parameters, whereupon a control signal is then also transmitted to the control device and the operation of the ground vehicle can be influenced by the evaluation unit here. The evaluation unit can be a separate (electronic) device, but the evaluation unit can also be part of the control system for controlling the ground vehicle itself. The (at least) one data-conductive connection between the evaluation unit and the controller and the sensor system can be realized wired or wirelessly.

[0015] The detection device is arranged for generating a signal that represents the (rearward) surrounding area of the ground vehicle. This signal can be interpreted by the evaluation unit and cause an instruction to the control system, by means of which the ground vehicle can be stopped under predefined operating conditions, in particular before a predefined safety distance from the (identified, predefined) object is reached. The detection device for identifying persons and / or objects located in the (rearward) travel path is connected to the evaluation unit and / or the control device.

[0016] The detection device is in particular provided for monitoring a protection area and / or an alarm area, i.e., for detecting persons, objects, etc. that enter during the (backward) travel of a ground vehicle there. Depending on the travel direction, speed, and / or steering deflection, different predefined areas can be monitored. Each predefined area can consist of an alarm area and a protection area, where, if necessary, multiple alarm areas and / or protection areas can also be predefined. If an alarm area is interrupted, the evaluation unit can cause the ground vehicle to (only) reduce its speed (without directly stopping). If a protection area is interrupted, the evaluation unit (automatically, i.e., especially without the active intervention of a person and / or directly based on an indication of the evaluation unit) triggers a braking function, where, for example, the drive device is separated from the voltage supply device (reliably interrupting the torque (STO)). If a protection area is no longer interrupted, the drive device of the ground vehicle can then be activated again and thus automatically continue to travel, for example, after 2 seconds.

[0017] The detection device (and, if necessary, also the evaluation unit and / or the control system) is provided for automatically switching the currently to-be-used protection area and / or alarm area based on the (current) position of the ground vehicle and / or the (currently) detected obstacles in the travel path of the ground vehicle.

[0018] According to a first example, the control system identifies a special travel cycle (e.g., based on speed, travel direction, etc.) or a travel section (e.g., based on a guiding section on the ground), where, based on these parameters, the correspondingly predefined protection area and / or alarm area of the detection device is automatically predefined / activated. For this purpose, data sets can exist in the control system, the evaluation unit, and / or the detection device, in which the protection area and / or alarm area is dimensioned or divided based on the position of the ground vehicle. The automatic switching can take place, for example, when driving into a defined supermarket.

[0019] Another example is that the control system (if necessary, using the evaluation unit and / or the detection device) identifies a specific pattern in the current protection area and / or alarm area and then automatically predefines / activates different predefined protection areas and / or alarm areas of the detection device. If, for example, a load carrier (sliding bench) is identified by means of its external wheels, the protection area and / or the alarm area is tapered, if necessary, so that the ground vehicle can be further repositioned and then the protection area and / or the alarm area extends between the wheels and under the load carrier.

[0020] Preferably, the control system includes a control unit for the desired driving direction and speed, a control unit for movement, and a control unit for the safety of the ground vehicle. The first control unit (manipulator control unit, Robot Control Unit, RCU), the second control unit (motion control unit, Motion Control Unit, MCU), and the third control unit (safety control unit, Safety Control Unit, SCU) can be components of the control system.

[0021] Advantageously, the detection device includes a laser scanner. The laser scanner uses laser light to scan a predefined surrounding area. Here, a laser beam is emitted by the scanner, which is then reflected again by the surrounding environment, objects, or obstacles and received again by the receiving optics. Here, the laser can be steered by a pivoting deflection mirror. The running time of the laser from the scanner to the re-reception is determined and evaluated, from which the distance to obstacles (persons, objects, etc.) in the scanned area can be inferred. An "image" can also be generated, which has the relative orientation of a plurality of detected objects to each other. Thus, a more complex analysis of the surrounding environment can also be carried out.

[0022] The laser scanner is preferably arranged at the rear of the ground vehicle. Thus, the viewing direction or the resulting protection area and / or warning area extends in particular from the rear of the ground vehicle over a predefined area, for example over the entire width of the ground vehicle.

[0023] Suitably, the control system includes an evaluation unit. Advantageously, the evaluation unit is integrated into the control system.

[0024] Preferably, the laser scanner is connected to the third control unit (SCU).

[0025] Advantageously, the second control unit (MCU) and the third control unit (SCU) are configured to check for obstacles in the surrounding environment by means of predefined protection areas and warning areas of the laser scanner.

[0026] Preferably, a plurality of protection areas (areas in front of, behind, and beside the ground vehicle) are predefined in the laser scanner.

[0027] Suitably, the third control unit (SCU) is configured to activate and / or deactivate the protection areas.

[0028] Preferably, the control system is configured to monitor the driving path of the ground vehicle by wheel odometry.

[0029] With the proposed ground vehicle, the safety control unit and the driving control unit check the surroundings for obstacles by means of the predefined protection zones and warning zones of the laser scanner. The safety control unit stops the vehicle at the latest if an unexpected object is detected in the protection zone. A plurality of protection zones (areas in front of, behind or beside the vehicle) are predefined in the laser scanner and can be activated or deactivated by the safety control unit.

[0030] Therefore, the ground vehicle can also be provided with a system for data processing, which includes means for carrying out the above-described method steps using the detection device. In particular, the system is provided for determining persons and / or objects located in the travel path by means of the detection device, in particular using an evaluation unit, wherein

[0031] - the protection zone and / or the warning zone can be switched automatically depending on the position of the ground vehicle and / or detected obstacles in the path of travel of the ground vehicle, and / or

[0032] If a (predeterminable) inadmissible change is detected (at least in the warning zone), a (undelayed) stop of the travel of the ground vehicle is brought about.

[0033] As a precaution, it should be pointed out that the elements are usually designated by numbers ("first", "second", ...) only for differentiation purposes and that no dependency or sequence of the elements needs to be predetermined. With regard to sensors, this means, for example, that their mounting (fixed, mobile) and / or position (on a support, fixture, etc.) can be freely selected independently of the name or according to the technical environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The invention and the technical field are described in detail below with the aid of the drawings. Identical components are identified with the same reference numerals. The drawings are schematic and are not provided for the purpose of illustrating the dimensional ratios. The descriptions explained with reference to individual details of a drawing are extractable and can be freely combined with the details from other drawings or the preceding descriptions, unless other results must be obtained for a person skilled in the art or such a combination is expressly prohibited. The drawings schematically show:

[0035] Figure 1 A top view of a driverless, autonomous ground vehicle with a control system and a detection device is shown;

[0036] Figure 2 shows a block diagram with a control system to which a laser scanner and a drive motor are connected;

[0037] Figure 3 shows a load with a loaded load and a laser scanner according to Figure 1Side view of a ground vehicle;

[0038] Figures 4a to 4e Shows a first embodiment of the operation of the ground vehicle proposed herein; and

[0039] Figures 5a to 5e Shows a second embodiment of the operation of the ground vehicle proposed herein. Detailed Description

[0040] Figure 1 Shows a top view of a driverless autonomous ground vehicle 1 having a control system 3 and a laser scanner 8.

[0041] The ground vehicle 1 proposed herein having a loading area 1.1 for a load 2 to be transported (see Figure 3 ) at least includes a control system 3 for controlling and maneuvering the ground vehicle 1 and an evaluation unit 4 which also generates, for example, signals for stopping the ground vehicle 1 (see Figure 2 ). A detection device 5 (see Figure 2 ) is connected to the control system 3, wherein the detection device 5 includes a laser scanner 8. The control system 3 includes a first control unit 9 for the desired travel direction and speed, a second control unit 10 for movement, and a third control unit 11 for the safety of the ground vehicle 1. The first motor for the travel movement of the ground vehicle 1 is denoted by 12 and the second motor for the height adjustment of the lifting device 14 (see Figure 2 ) is denoted by 13. The first rotation sensor (rated speed) is denoted by 15 and the second rotation sensor is denoted by 16. The movement directions are denoted by A, B. The ground vehicle 1 can be an autonomous shuttle (AS).

[0042] Figure 2 Illustrates a block diagram having a control system 3 for the ground vehicle 1 proposed herein. The laser scanner 8 is connected to the electronic control system 3 via an evaluation unit 4 by a data-conducting connection 17. The second control unit 10 is connected to the motor 12 via the first speed sensor 15 (rated speed). The second speed sensor 16 is connected to the third control unit 11. A braking system 18 is connected to the control system 3, which can generate signals to the first motor 12 to stop the ground vehicle 1. The braking system 18 can also act on the ground vehicle 1 alone or in combination with the first motor 12. In addition, the second motor 13 for driving the lifting device 14 is connected to the control system 3. The detection device 5 can also be considered for identifying the position of the lifting unit 14. The memory element is denoted by 19.

[0043] Figure 3 Shows with a loaded load 2 according toFigure 1 Side view of the ground vehicle 1. Here, the load 2 consists of the loaded goods 21 and the transporter 22, and the loaded goods 21 can be transported by the transporter. The wheels of the ground vehicle 1 are denoted by 20.1, 20.2, and 20.3. The wheels of the transporter 22 are denoted by 23.1 and 23.2. The laser scanner 8 is installed at the rear of the ground vehicle 1. The laser field of view 8.1 is directed away from the ground vehicle 1. The load sensor (azimuth sensor) is denoted by 6.

[0044] Figures 4 and 5 show two embodiments of the operation of the ground vehicle 1. The narrow protection zone is denoted by 24 and the wide warning zone of the laser scanner 8 is denoted by 25.

[0045] Figures 4a to 4e Describe the first embodiment of the operation of the ground vehicle proposed herein. For this purpose, the basic process logic can be summarized as follows:

[0046] 1. The first control unit 9 transmits the desired driving direction and speed to the second control unit 10.

[0047] 2. The second control unit 10 further transmits the desired driving direction to the third control unit 11, calculates the rated speed, and transmits it to the motor.

[0048] 3. The safe SIL2 rotation sensor transmits the actual speed of the motor to the third control unit 11.

[0049] 4. The third control unit 11 identifies when the warning zone 25 of the rear laser scanner 8 is triggered and switches the laser scanner 8 to the narrower protection zone 24.

[0050] 5. The third control unit 11 calculates the movement path (safe wheel ranging) from the actual speed, and when the pre-given movement path (Y) is reached, the speed is set to v = 0 mm / s through the second control unit 10. (The rated speed of the third control unit 11 takes precedence over the desired speed of the first control unit 9.)

[0051] Specifically, the process is as follows:

[0052] Step 1:

[0053] After driving into the supermarket, in addition to the protection zone 24, the warning zone 25 is also accessed, through which the unloading position or the next transporter 22 (sliding table) already located in the supermarket should be identified ( Figure 4a ).

[0054] Step 2:

[0055] The ground vehicle 1 drives backward for such a long time until the alarm zone 25 is triggered. Then it switches to a narrower protection zone 24. This protection zone 24 can not only identify trapped persons, but also place the transporter 22 on the existing (fixed) transporters 22.1, 22.2, 22.3, because the protection zone 24 normally observes under the said transporter ( Figure 4b , 4c ).

[0056] Step 3:

[0057] The ground vehicle 1 continues to drive backward through the section Y monitored by the safe wheel distance measurement and drops the transported goods ( Figure 4d , 4e ).

[0058] After the obstacle in the supermarket has been identified by the backward laser scanner 8 (by means of the alarm zone 25), the activation of the narrower protection area 24 enables the identification of trapped persons. The ground vehicle 1 stops without touching and no additional emergency stop button is required. Under normal circumstances (without trapped persons), the narrower protection zone 24 "observes" under the transported goods (transporter 22), and the loaded transported goods are placed thereon, making the best use of the space in the "supermarket lane".

[0059] A particular advantage also lies in the improved personnel protection when unloading transported goods in the danger zone, the elimination of the additional emergency stop button and the reduced space requirement.

[0060] Figures 5a to 5e The second implementation manner of the operation of the ground vehicle proposed herein is illustrated. For this purpose, the basic process logic can be summarized as follows:

[0061] 1. The first control unit 9 transmits the desired driving direction and speed to the second control unit 10.

[0062] 2. The second control unit 10 further transmits the desired driving direction to the third control unit 11, calculates the rated speed, and transmits it to the motor.

[0063] 3. The safe SIL2 rotation sensor transmits the actual speed of the motor to the third control unit 11.

[0064] 4. The third control unit 11 calculates the movement path (safe wheel distance measurement) from the actual speed, switches the required laser scanner area according to the desired driving direction, and forcibly maintains it on the predefined movement path (X).

[0065] The process specifically:

[0066] Step 1:

[0067] After the ground conveyance tool 1 has turned onto the middle lane 27, it starts to move backward ( Figure 5a 、 5b ).

[0068] Step 2:

[0069] Activate the protection zone 24 of the rear laser scanner 8 and move the ground conveyance tool backward for a section of X centimeters. The X centimeters are monitored by safe wheel odometry and thus ensure that the ground conveyance tool safely drives into the supermarket (hazardous area). ( Figure 5c 、 5d )

[0070] Ensure by safe wheel odometry monitoring that the switch to the narrow protection zone 24 is only made in the hazardous area. That is, select the laser scanner area required for safely crossing the sidewalk 26 before starting to move backward and forcibly maintain it on the predefined movement path.

[0071] Step 3:

[0072] Furthermore, the ground conveyance tool 1 moves backward and drops the load 2 (the conveyed goods). ( Figure 5e )

[0073] Advantageously, when driving into the hazardous area, it safely drives over the sidewalk 26. Here, it is safely prevented that the laser scanner 8 is turned off or prematurely switched to the narrow protection zone 24 with PLd.

[0074] The driverless, autonomously operating ground conveyance tool 1 (AGV) proposed here is preferably used, for example, in factories, warehouses, supermarkets or hospitals. Based on sensors such as laser scanners, inductive proximity sensors, ultrasonic sensors and / or 3D cameras, collisions (especially with people and / or objects) and / or disorientation are avoided. It conveys, for example, pallets, boxes, racks, parts or small load carriers (KLT) with or without a conveyance cart (sliding table).

[0075] List of reference numerals

[0076] 1 Ground conveyance tool

[0077] 1.1 Loading area

[0078] 2 Load

[0079] 3 Control system

[0080] 4 Evaluation unit

[0081] 5 Detection device

[0082] 6 Load sensor

[0083] 7 Sensor system

[0084] 8 Laser scanner

[0085] 8.1 Laser field of view

[0086] 9 First control unit

[0087] 10 Second control unit

[0088] 11 Third control unit

[0089] 12 First motor

[0090] 13 Second motor

[0091] 14 Lifting device

[0092] 15 First rotation sensor

[0093] 16 Second rotation sensor

[0094] 17 Connection for transmitting data

[0095] 18 Braking system

[0096] 19 Memory element

[0097] 20.1, 20.2, 20.3 Wheels of the ground vehicle

[0098] 21 Loaded goods

[0099] 22 Conveyor vehicle

[0100] 22.1, 22.2, 22.3 Fixed conveyor vehicle

[0101] 23.1, 23.2 Wheels of the conveyor vehicle

[0102] 24 Protection area

[0103] 25 Alarm area

[0104] 26 Sidewalk

[0105] 27 Intermediate lane

[0106] A, B Directions of movement

[0107] X, Y Sections of the road.

Claims

1. A ground transportation vehicle (1) configured to operate for driverless autonomous movement, the ground transportation vehicle for a load (2) to be transported and comprising at least: - A control system (3) that controls and maneuvers the ground vehicle (1), - An evaluation unit (4) that generates a signal for stopping the ground vehicle (1), wherein a detection device (5) for identifying persons and / or objects located in the travel path is connected to the control system (3), wherein the control system (3) is arranged to check the protection zone (24) or warning zone (25) of the detection device (5), and wherein the protection zone (24) can be automatically switched between a wide warning zone (25) and a narrower protection zone (24) according to the position of the ground vehicle (1), or the warning zone (25) can be automatically switched between a wide warning zone (25) and a narrower protection zone (24) according to an obstacle detected in the travel path of the ground vehicle (1).

2. The ground transportation vehicle (1) according to claim 1, wherein, The control system (3) includes a first control unit (9) for the desired travel direction and speed, a second control unit (10) for movement, and a third control unit (11) for the safety of the ground vehicle (1).

3. The ground transportation vehicle (1) according to claim 2, wherein, The detection device (5) includes a laser scanner (8).

4. The ground transportation vehicle (1) according to claim 3, wherein, The laser scanner (8) is arranged at the rear of the ground vehicle (1).

5. The ground transportation vehicle (1) according to claim 1, wherein, The control system (3) includes an evaluation unit (4).

6. The ground transportation vehicle (1) according to claim 3, wherein, The laser scanner (8) is connected to the third control unit (11).

7. The ground transportation vehicle (1) according to claim 3, wherein, The second control unit (10) and the third control unit (11) are arranged to check for obstacles in the surroundings by means of the predefined protection zone (24) and warning zone (25) of the laser scanner (8).

8. The ground transportation vehicle (1) according to claim 3, wherein, A plurality of protection zones (24) are predefined in the laser scanner (8).

9. The ground transportation vehicle (1) according to claim 2, wherein, The third control unit (11) is arranged to activate or deactivate the protection zone (24).

10. The ground transportation vehicle (1) according to any one of claims 1 to 9, wherein, The control system (3) is arranged to monitor the travel path of the ground vehicle (1) by wheel odometry.

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