Ground transport vehicle for autonomous operation without a driver, provided for loads to be transported

Abstract

The invention relates to a ground transport vehicle (1) for transporting a load (2) to be transported, which is configured for autonomous operation without a driver, the ground transport vehicle comprising at least: a control system (3) which controls and operates the ground transport vehicle (1); an evaluation unit (4) which generates a signal for stopping the ground transport vehicle (1), wherein a detection device (5) for identifying the distance of the load (2) to be loaded is connected to the control system (3), wherein the detection device (5) comprises at least one sensor, and wherein the control system (3) is configured to switch the travel speed of the ground transport vehicle (1) depending on the distance to the load (2) to be received.

Description

Technical Field

[0001] The invention relates to a ground transport vehicle (automatic guided vehicle, AGV) for transporting loads, which is designed for autonomous operation without a driver. The invention is particularly applicable to robotic transport vehicles for transporting loads. It also includes lifting ground transport vehicles and non-stackable lift trucks and corresponding combinations. Background Art

[0002] With the advancement of automation technology, the operation of loads is becoming more and more important.

[0003] Autonomous ground vehicles that detect the load to be picked up by means of inductive sensors must approach the load very early and at a greatly reduced speed (particularly taking into account reaction times and / or braking times) due to the limited range of conventional inductive sensors (approximately 1 cm). Furthermore, if the load to be picked up in the supermarket (placement area or storage area for the load) is not detected (there is not enough inductive material in the detection area of ​​the sensor), there is the risk that the ground vehicle will remove the transported goods that are present from the supermarket. Summary of the invention

[0004] Starting from this, the object of the present invention is to provide a ground vehicle for transporting loads, which is designed for autonomous operation without a driver and which reduces or even avoids the disadvantages. In particular, an increase in the safe speed during the load reception should be achieved in a structurally simple manner. In particular, an increase in personal protection should be achieved by preventing the transported goods from moving out of the supermarket. In addition, the movement of the ground vehicle should be stopped safely in order to prevent collisions.

[0005] These objects are solved by a ground transport vehicle according to the independent claims. Further embodiments of the invention are given in the dependent claims. It should be noted that the description, in particular in conjunction with the drawings, implements further details and improvements of the invention, which can be combined with the features in the claims.

[0006] A ground vehicle for transporting loads, which is designed for autonomous operation without a driver, contributes to this, and comprises at least:

[0007] - a control system which controls and operates the ground transport vehicle,

[0008] - an evaluation unit which generates a signal for stopping the ground vehicle, wherein a detection device for detecting the distance to a load to be picked up is connected to the control system, wherein the detection device comprises a sensor, and wherein the control system is configured to switch the travel speed of the ground vehicle as a function of the distance to the load to be picked up (in particular actively or automatically).

[0009] The ground transport proposed here has the advantage that the load to be received is identified by an inductive sensor. Due to the limited range of the inductive sensor (1 cm), the AGV approaches the last centimeter of the load at a greatly reduced speed. The section of road that the AGV passes between the identification of the transport vehicle (sliding platform, Dolly) by the laser scanner and the identification of the load by the inductive sensor is, for example, about 80 cm. The increase in safe speed is achieved in the following way, that is, the first 70 cm of this section is monitored by means of safe wheel distance measurement (for example, by means of a laser scanner) and the speed is reduced only afterwards. Preventing the transported goods from being removed from the supermarket and the resulting increase in personal protection is achieved in the following way, that is, when the load to be received is not identified, the backward travel of the AGV is ended after a total of 90 cm by means of safe wheel distance measurement.

[0010] The ground vehicle without a driver can be a vehicle that is determined to be used for active driving, powered, and may include any trailer if necessary. For this reason, the ground vehicle can cooperate with a guidance system that predetermines a driving route in the ground or in the surroundings.

[0011] A "load" is an object to be handled, including its mass, size, condition and / or arrangement. A load can consist (only) of the load. A load can also include the load and the transport device for the load, such as a transport vehicle, a pallet, a trolley, etc. "Load handling" that can be performed by a ground transport vehicle is understood in particular to mean lifting, lowering, load transfer and / or load handling.

[0012] The control system has as its content an automatic device which controls (e.g. activates / deactivates) and operates (optionally monitors via sensors) the ground vehicle and its associated devices. The system of the driverless ground vehicle comprises a control system which can be part of the ground vehicle and / or separate therefrom. The control system can comprise a computing unit which is arranged in or on the ground vehicle.

[0013] The evaluation unit can be connected to the sensor system (e.g., a detection device) preferably in an electrically conductive and data-conducting manner and is configured to process its signals. The evaluation unit is particularly configured to analyze the data of the sensor system or the detection device so that the distance to the load to be received (in the area behind the ground transportation vehicle) can be clearly detected or determined. The distance determined in the evaluation unit can be adjusted or influenced by predetermined (e.g., stored and / or set) parameters, wherein the control signal is then also transmitted to the control device and the operation of the ground transportation vehicle can be influenced by the evaluation unit. The evaluation unit can be a separate (electronic) device, but the evaluation unit can also be part of a control system for controlling the ground transportation vehicle itself. (At least) a data-conducting connection between the evaluation unit and the controller and the sensor system can be implemented wired or wirelessly.

[0014] The detection device is configured to generate a signal that indicates the (rearward) surrounding area of ​​the ground vehicle. The signal can be interpreted by the evaluation unit and can result in a command to the control system, by which the ground vehicle can be stopped by means of a braking system under predefined operating conditions, in particular before a predefined safety distance to a (identified, predefined) object is fallen below. The detection device for detecting a load located in the (rearward) travel path is connected to the evaluation unit and / or the control device.

[0015] The detection device has (at least) one sensor which is designed and arranged to detect the arrangement of a load (to be received and / or held) in the loading area of ​​the ground vehicle and / or to monitor the (rearward) surrounding area of ​​the ground vehicle and which is in particular connected to the control system.

[0016] The detection device is particularly provided for monitoring the protection zone and / or the warning zone, i.e. detecting there the personnel, objects etc. entering during the (backward) travel of the ground transportation vehicle. The areas predefined differently can be monitored according to the travel direction, speed and / or steering deflection. Each predefined area can be composed of a warning zone and a protection zone, wherein a plurality of warning zones and / or protection zones can also be predefined if necessary. If a warning zone is interrupted, the evaluation unit can cause the ground transportation vehicle to (only) reduce the speed (without stopping directly). If a protection zone is interrupted, the evaluation unit (automatically, i.e., especially in the absence of the active action of the personnel and / or directly based on the indication of the evaluation unit) triggers the braking function, wherein, for example, the drive device is separated from the voltage supply device (reliably disconnecting the torque (STO)). If a protection zone is no longer interrupted, the drive device of the ground transportation vehicle can be activated again and therefore automatically continues to travel after, for example, 2 seconds.

[0017] The control system is configured to switch the travel speed of the ground vehicle as a function of the distance to the load to be received (in particular actively or automatically), in particular in such a way that, when a first distance is reached, a first speed reduction is initiated, and when a second distance is reached, a second speed reduction is initiated. The first and / or second distance can be determined by sensors and / or by calculation, preferably the two distances are determined using different sensors. Preferably, the speed is reduced several times, in particular twice or three times, when approaching the load. This is particularly based on the fact that after the reduction, a (substantially) constant speed is temporarily predetermined.

[0018] The first distance from the load to be received, for example, a distance of about 80 cm from the front edge of the loading area of ​​the ground vehicle, can be identified with a laser scanner. If this first distance is reached, the speed of (backward) travel is (automatically) reduced by a predetermined value, so that the ground vehicle then approaches more slowly. When it is determined (by a sensor and / or by calculation) that a second distance has been reached, for example, about 10 cm from the front edge of the loading area of ​​the ground vehicle, the speed of (backward) travel is (automatically) further reduced by a predetermined value, so that the ground vehicle then approaches more slowly. When a load is identified by the proximity sensor of the ground vehicle at the front edge of the loading area of ​​the ground vehicle, then, for example, the stopping of the travel movement of the ground vehicle can be achieved.

[0019] Preferably, the control system comprises 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 (Robot Control Unit, RCU), the second control unit (Motion Control Unit, MCU) and the third control unit (Safety Control Unit, SCU) can be components of the control system.

[0020] Advantageously, the sensor system comprises at least one inductive sensor. The inductive sensor can be designed as an inductive proximity actuator or an inductive displacement sensor.

[0021] Preferably, the inductive sensor is a proximity sensor. Suitably, the inductive sensor is arranged in an adjacent region at the rearward end of the ground transport or in the vicinity of the loading region. The inductive sensor can detect loaded goods on the ground transport, a transport vehicle ("sliding platform") on the ground transport or loaded goods arranged on a transport vehicle.

[0022] The detection device preferably comprises a laser scanner. The laser scanner uses a laser to scan a predetermined surrounding area. In this case, a laser beam is emitted by the scanner, which is then reflected again by the surroundings, objects or obstacles and received again by the receiving optical device. In this case, the laser can be deflected by a pivoting deflection mirror. The running time of the laser from the scanner to the re-reception is determined and evaluated, wherein the distance to the obstacles in the scanning area can be inferred from this. It is also possible to generate a kind of "image" which has the relative orientation of multiple detected objects to each other. In this way, a more complex analysis of the surrounding environment can also be performed. The sensor system can be arranged in this way so that the inductive sensor (partially) monitors the loading area and the laser scanner (partially) monitors the adjacent surrounding area.

[0023] The laser scanner is preferably arranged at the rear of the underground vehicle and, if appropriate, is oriented toward the oncoming driving area.

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

[0025] Preferably, the control system comprises an evaluation unit, or the evaluation unit is integrated into the control system.

[0026] The second control unit (MCU) and the third control unit (SCU) are expediently provided for switching the driving speed of the ground vehicle.

[0027] Preferably, the control system is configured to monitor the travel path of the ground vehicle by means of wheel odometry.

[0028] Advantageously, the inductive sensor is connected to a third control unit (SCU).

[0029] The proposed ground vehicle improves load handling in a robotic vehicle. To this end, a specific process is required, including load detection and reliable measurement of the travel path using various sensors (safe wheel odometry).

[0030] Therefore, the ground vehicle can also be equipped with a system for data processing, which includes means for carrying out the above-described method steps using a detection device. In particular, the system is configured to determine the distance to the load to be received by means of a detection device or a sensor, in particular when using an evaluation unit, wherein

[0031] - switching the speed of the ground transport vehicle (possibly multiple times) depending on the distance to the load to be picked up, and / or

[0032] If a (predeterminable) inadmissible change is detected (at least in the warning zone), the travel of the ground vehicle is stopped (without delay).

[0033] As a precaution, it should be pointed out that usually the elements are designated with 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, following) 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 situations 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 A block diagram is shown with a control system to which an inductive sensor and a laser scanner are connected;

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

[0038] Figures 4a to 4e Shown according to Figure 3 A top view of a ground vehicle with a loaded load, with a laser field of view and a flow diagram for operating the ground vehicle presented here. DETAILED DESCRIPTION

[0039] Figure 1 The figure shows a top view of an autonomous ground vehicle 1 without a driver, which has a control system 3 , a load sensor 6 (position sensor) and a laser scanner 8 .

[0040] The present invention has a load 2 to be transported (see Figure 3 ) comprises at least a control system 3 for controlling and operating the ground vehicle 1 and an evaluation unit 4 for generating a signal for stopping the ground vehicle 1 (see Figure 2 ). Detection device 5 (see Figure 2) for detecting the arrangement of the load 2 and is connected to a control system 3, wherein the detection device 5 comprises an inductive sensor as a load sensor 6 and a laser scanner 8. The control system 3 comprises a first control unit 9 for the desired direction of travel and speed, a second control unit 10 for the movement and a third control unit 11 for the safety of the ground vehicle 1. 12 denotes a first motor for the travel movement of the ground vehicle 1 and 13 denotes a lifting device 14 (see Figure 2 ) is a second motor for height adjustment. 15 denotes a first rotary inductor (rated speed) and 16 denotes a second rotary inductor, for example a SIL-2 rotary inductor. A and B denote the directions of movement. The ground transport 1 may be an active shuttle (AS).

[0041] Figure 2 The block diagram of the control system 3 for the ground vehicle 1 proposed here is shown. The load sensor 6 and the laser scanner 8 are connected to the electronic control system 3 via the evaluation unit 4 via the data-conducting connection 17. The second control unit 10 is connected to the first 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 a signal 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, a second motor 13 for driving the lifting device 14 is connected to the control system 3. The detection device 5 can also be used to detect the position of the lifting unit 14. 19 represents a memory element.

[0042] Figure 3 shows a load 2 having a load according to Figure 1 1 , and an inductive sensor, such as an inductive proximity sensor, as a load sensor 6 is shown. The load sensor 6 is mounted on the back side of the loading surface 1.1 of the ground vehicle 1 and is oriented in the direction of the load 2. Here, the load 2 consists of a load 21 and a transport vehicle 22, and the load 21 can be transported by the transport vehicle. The wheels of the ground vehicle 1 are represented by 20.1, 20.2 and 20.3. The wheels of the transport vehicle 22 are represented by 23.1 and 23.2. The laser scanner 8 is mounted on the rear of the ground vehicle 1. The laser field of view 8.1 is oriented in the direction away from the ground vehicle 1.

[0043] Figures 4a to 4e Show according to Figure 2 A top view of a ground transport vehicle 1 with loaded goods, which has a laser scanner 8 and a laser field of view 8.1 and a flow chart. For this purpose, the basic process logic can be summarized as follows:

[0044] 1. The first control unit 9 transmits the desired driving direction and speed to the second control unit 10.

[0045] 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.

[0046] 3. The safe SIL2 rotation sensor transmits the actual speed of the motor to the third control unit 11.

[0047] 4. The third control unit 11 detects when the warning zone 25 of the rear laser scanner 8 has been triggered and switches the laser scanner 8 to the narrower protection zone 24 .

[0048] 5. The third control unit 11 detects 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. The third control unit 11 calculates the movement path from the actual speed (safe wheel distance measurement) and predetermines the increased speed v=100 mm / s for the second control unit 10. (The setpoint speed of the third control unit 11 has priority over the desired speed of the first control unit 9)

[0049] 6. After a safely monitored movement path of 70 cm, the third control unit 11 specifies to the second control unit 10 the reduced speed required for detection by the inductive sensor (load sensor 6 ).

[0050] 7. After the transport vehicle 22 (sliding platform) to be received has been identified by the inductive sensor, the third control unit 11 sets the speed to V = 0 mm / s via the second control unit 10 .

[0051] 8. If no transport vehicle 22 is detected after a total of 90 cm of safely monitored movement path, the third control unit 11 sets the speed to v=0 mm / s via the second control unit 10 .

[0052] The process is specifically:

[0053] Step 1:

[0054] After the transport vehicle 22 to be received has been identified (section a), the vehicle switches to the narrower protection zone 24 and the road vehicle 1 travels over a section of 70 cm monitored by safe wheel distance measurement (v=100 mm / s) (see Figure 4a , 4b ).

[0055] Step 2:

[0056] After that, due to the limited range (approximately 1 cm, section c) of the inductive load sensor 6 ("sliding platform detection" sensor) mounted on the rear wall of the rear part of the front structure of the ground vehicle 1, the ground vehicle 1 continues to move backwards at a reduced speed until the transport vehicle 22 is detected and the ground vehicle 1 stops (see Figure 4c , 4d ).

[0057] Step 3:

[0058] If the transport vehicle 22 is not detected for some reason, a safe distance measurement ensures that the ground vehicle stops moving backwards after a maximum of 90 cm (section b) (see Figure 4e ).

[0059] The driverless, autonomous ground transport vehicle 1 (AGV) proposed here is preferably used, for example, in factories, warehouses, supermarkets or hospitals. Collisions (especially with people and / or objects) and / or disorientation are avoided based on sensors, such as laser scanners, inductive proximity sensors, ultrasonic sensors and / or 3D cameras. Transport of, for example, pallets, boxes, racks, parts or small load carriers (KLT) with or without a transport trolley (sliding platform).

[0060] Reference numerals list

[0061] 1 Ground transportation

[0062] 1.1 Loading area

[0063] 2 Load

[0064] 3 Control system

[0065] 4 Evaluation Units

[0066] 5 Detection device

[0067] 6 Load sensor

[0068] 7 Sensor system

[0069] 8 Laser Scanner

[0070] 8.1 Laser Field of View

[0071] 9 First control unit

[0072] 10 Second control unit

[0073] 11 Third control unit

[0074] 12 First Motor

[0075] 13 Second Motor

[0076] 14 Lifting device

[0077] 15. First Rotation Sensor

[0078] 16 Second rotation sensor

[0079] 17 Connections for conducting data

[0080] 18 Braking system

[0081] 19 Memory Components

[0082] 20.1, 20.2, 20.3 Wheels of ground transport vehicles

[0083] 21 Loading Cargo

[0084] 22 Transport vehicle

[0085] 22.1, 22.2, 22.3 Fixed transport vehicles

[0086] 23.1, 23.2 Wheels of transport vehicles

[0087] 24 Protected Areas

[0088] 25 Alarm Zone

[0089] A, B Movement direction

[0090] a The first section

[0091] b Second section

[0092] c The third section.

Claims

1. A ground transport vehicle (1) for transporting a load (2) to be transported, the ground transport vehicle being configured for autonomous operation without a driver, the ground transport vehicle comprising at least: - a control system (3) which controls and operates the ground transport vehicle (1), - an evaluation unit (4) which generates a signal for stopping the ground vehicle (1), A detection device (5) for identifying the distance of a load (2) to be loaded is connected to a control system (3), wherein the detection device (5) comprises an inductive load sensor (6) arranged on the back side of a loading surface (1.1) of the ground transport vehicle (1) and oriented in the direction of the load (2) to be loaded, wherein the load (2) to be loaded is composed of a load (21) and a transport vehicle (22), and the load (21) can be transported by means of the transport vehicle (22), and wherein the control system (3) is configured to switch the travel speed of the ground transport vehicle (1) according to the distance from the load (2) to be received, wherein the detection device (5) further comprises a laser scanner (8) arranged at the rear of the ground transport vehicle (1).

2. The ground transportation vehicle (1) according to claim 1, wherein: The control system (3) comprises a first control unit (9) for the desired driving direction and speed, a second control unit (10) for the 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 laser scanner (8) is connected to the third control unit (10).

4. The ground transportation vehicle (1) according to claim 1 or 2, wherein: The control system (3) comprises the evaluation unit (4).

5. The ground transportation vehicle (1) according to claim 2, wherein: The second control unit (9) and the third control unit (10) are configured to switch the travel speed of the ground transportation vehicle (1).

6. The ground transportation vehicle (1) according to claim 1 or 2, wherein: The control system (3) is configured to monitor the travel path of the ground vehicle (1) by wheel odometry.

7. The ground transportation vehicle (1) according to claim 2, wherein: The inductive load sensor (6) is connected to the third control unit (10).

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