A ground vehicle configured to operate for driverless autonomous operation

Abstract

The present invention relates to a ground transportation vehicle (1) configured for driverless, autonomous operation, having a loading area (1.1) for a load (2) to be transported, the ground transportation vehicle comprising at least: a control system (3) for controlling and maneuvering the ground transportation vehicle (1); an evaluation unit (4) for generating a signal for stopping the ground transportation vehicle (1), wherein a detection device (5) for identifying the arrangement of the load (2) in the loading area (1.1) is connected to the control system (3), and wherein the detection device (5) comprises a redundant sensor system (7).

Description

Field of the Invention

[0001] The present invention relates to a driverless, autonomous ground vehicle (automated guided vehicle, AGV) for a load to be transported. The present invention is particularly applicable to robotic transport vehicles for transporting loads. It also includes lift-type ground vehicles and non-stackable lift trucks and combinations thereof. Background Art

[0002] With the progress of automation technology, the handling of loads has become increasingly important.

[0003] When a ground vehicle lifts a load to be transported for transportation, it is necessary to ensure that the load remains in a fixed position during transportation, or that the sliding of the load does not result in an unsafe state. For example, the sliding of the load can be prevented in the following ways:

[0004] 1) A form-fitting receiving device (locking device) that is activated after loading and before the vehicle starts moving, or

[0005] 2) A force-fitting receiving portion.

[0006] Variant 1) can completely prevent sliding (in the case of appropriate correct design). Variant 2) is based on the normal force of the loaded goods, and thus there is insecurity due to dynamic forces that are not predictable in all driving situations. For example, inertial forces acting against the normal force may occur due to ground undulations or at the transition from a slope to a flat surface. If the inertial force is large enough to cancel or at least significantly reduce the normal force, the load will move out of the specified position. Summary of the Invention

[0007] Starting from this, the object of the present invention is to provide a ground vehicle that is configured for driverless, autonomous operation, which alleviates or even avoids the above-mentioned disadvantages. In particular, it should be possible to prevent an unsafe state caused by the sliding of the transported goods in a structurally simple manner. This should be ensured especially when the transported goods are supported on rollers. In addition, in the case of sliding, the movement of the ground vehicle should be reliably stopped.

[0008] These objects are solved by a ground vehicle according to the independent claims. Other embodiments of the present invention are given in the dependent claims. It should be noted that other details and improvements for implementing the present invention, especially in combination with the description of the drawings, can be combined with the features in the claims.

[0009] The following ground vehicle is helpful for this purpose. The ground vehicle is configured for driverless, autonomous operation, has a loading area for a load to be transported, and at least includes:

[0010] - A control system that controls and maneuvers the ground vehicle,

[0011] - An evaluation unit that generates a signal for stopping the ground vehicle,

[0012] wherein a detection device for identifying the arrangement of the load in the loading area is connected to the control system, and wherein the detection device includes a redundant sensor system.

[0013] The advantages of the ground vehicle proposed herein are that the orientation of the loaded goods is continuously monitored, the movement of the load is identified, and the vehicle can be safely stopped without causing harm to surrounding objects. In particular, enhanced safety is achieved by additionally monitoring the load position. Other advantages are that costs are reduced and wear is eliminated (especially by omitting mechanical components and associated actuators for anchoring the load and (re)using existing sensor components) with the same safety as known form-fitting receiving devices.

[0014] The driverless ground vehicle can refer to a power-driven vehicle determined for autonomous driving, optionally including any trailers. To this end, the ground vehicle can cooperate with a guiding system in the ground or the surrounding environment that predefines the driving route.

[0015] "Load" refers to the object to be operated, including its mass, dimensions, state, and / or arrangement. The load can consist (only) of the loaded goods. The load can also include the loaded goods and the conveying devices for the loaded goods, such as conveyors, pallets, hand trucks (Bodenroller), etc. "Load operation" that can be performed by the ground vehicle is particularly understood as lifting, lowering, load transfer, and / or load handling.

[0016] The control system has an automatic device as its content, which controls (e.g., activates / deactivates) and maneuvers (optionally monitored by sensors) the ground vehicle and its associated devices. The system of the driverless ground vehicle includes such a control system, which can be part of the ground vehicle and / or separate from it. The control system can include a computing unit that is provided in or on the ground vehicle.

[0017] The evaluation unit is preferably conductively and data-conductively connected to the sensor system and is set up to process its signals. The evaluation unit is in particular set up to analyze the data of the sensor system of a ground vehicle, such that in particular the load can be clearly detected or determined with respect to its orientation / position relative to the loading area of the ground vehicle. The orientation determined in the evaluation unit can be adjusted and / or influenced using predefined (for example 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 hereby 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 vehicle itself. The (at least) one data-conducting connection between the evaluation unit and the controller and the sensor system can be realized either wired or wirelessly.

[0018] The detection device is set up to generate a signal representing the loading state and / or a change in the loading state. This signal can be interpreted by the evaluation unit and trigger a command to the control system, by means of which the ground vehicle can be brought to a standstill under predefined operating conditions by means of the braking system, in particular before a fixed part (partially) leaves the ground vehicle and / or the load (partially) leaves in particular the loading area and / or hits a person. The detection device for identifying the arrangement of the load, in particular the slipping of the load and / or for the positioning of the load, is connected to the evaluation unit and / or the control device.

[0019] The detection device comprises at least one fail-safe, redundant sensor system. "Redundant" in the context in particular means that there are at least 2 (independent and / or, if necessary, of different types) detection means or sensors. These detection means or sensors are in particular set up such that they can fully and independently of one another carry out their measuring function or signal transmission.

[0020] Preferably, the control system comprises a control unit for the desired direction and speed of travel, a control unit for the movement, and a control unit for the safety of the ground vehicle. The first control unit (manipulator control unit, RobotControl Unit, RCU), the second control unit (movement control unit, Motion Control Unit, MCU), and the third control unit (safety control unit, Safety Control Unit, SCU) are preferably components of the control system.

[0021] Advantageously, the sensor system comprises at least one inductive sensor. The inductive sensor can be configured as an inductive proximity actuator or an inductive displacement sensor.

[0022] Preferably, the inductive sensor is a proximity sensor. Suitably, the inductive sensor is arranged on the rear end of the ground vehicle in the adjacent area of the loading area or near the loading area. The inductive sensor can detect the loaded goods on the ground vehicle, the transporter on the ground vehicle ("sliding table, dolly") or the loaded goods arranged on the transporter.

[0023] Preferably, the inductive sensor has an inherent safety function (so-called "safe" sensor). The inductive safety sensor arranged in this way can be protected from cable breakage, for example, or can enable continuous inspection of its function. Therefore, the sensor can include at least two measuring lines and / or sensor units, so that there is fault protection.

[0024] Advantageously, there is a combination consisting of a "simple" inductive sensor without an inherent safety function and 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 deflected by a pivoting deflecting mirror. The running time of the laser from the scanner to the re-reception is determined and evaluated, and from this, the distance to the obstacles in the scanning area can be inferred. It is also possible to generate an "image" that has the relative orientations of multiple detected objects to each other. Thus, a more complex analysis of the surrounding environment can also be carried out. The sensor system can be arranged such that the inductive sensor (partially) monitors the loading area and the laser scanner (partially) monitors the adjacent surrounding area. In this way, a "redundant" system is also set up.

[0025] The laser scanner is preferably arranged at the rear of the ground vehicle and is oriented towards the return travel area if necessary.

[0026] Suitably, the inductive sensor with a safety function or the combination consisting of an inductive sensor without a safety function and a laser scanner is connected to a third control unit (SCU).

[0027] Preferably, the second control unit and the third control unit are set to identify a sliding load and stop the ground vehicle.

[0028] Advantageously, the evaluation unit is integrated into the control system.

[0029] Preferably, the load includes the loaded goods and / or the transporter for the loaded goods.

[0030] With the ground vehicle presented here, a sliding load is recognized by the driving control device and the safety control device and causes the vehicle to stop. Option 1 provides for a "safe" inductive proximity sensor located at the rear of the loading surface or at the edge of the loading area. Option 2 is embodied in the combination of a "simple" inductive proximity sensor located at the rear of the loading surface or at the edge of the loading area with a rear laser scanner sensor.

[0031] Accordingly, the ground vehicle can also be implemented as having a system for data processing, which system includes means for carrying out the above steps of the method using a redundant control system. In particular, the system is arranged to determine, especially in the case of using an evaluation unit, changes in the orientation and / or position of the load relative to the loading area by means of a redundant control system, wherein, upon determining a (predeterminable) impermissible change, the driving of the ground vehicle is caused to stop (without delay).

[0032] As a precautionary measure, it should be noted that elements are usually designated only by numbers ("first", "second",...) for the sake of distinction and that no element dependencies or sequences need to be predetermined. With regard to the sensors, this means, for example, that their installation (fixed, following) and / or position (on carriers, fixtures, etc.) can be freely selected independently of the name or selected according to the technical environment. Description of the Drawings

[0033] The present invention and the technical field are explained in detail below with the aid of the drawings. Here, identical components are identified by identical reference numerals. The drawings are schematic and not provided to illustrate dimensional ratios. The explanations set forth with respect to the individual details of one drawing are extractable and can be freely combined with the circumstances from other drawings or the foregoing explanations, unless it necessarily results otherwise for a person skilled in the art or such a combination is expressly prohibited. Schematically shown:

[0034] Figure 1 A top view of a driverless, autonomously operating ground vehicle having a control system and a detection device is shown;

[0035] Figure 2 A block diagram of a control system is shown, to which an inductive sensor, a laser scanner, an evaluation unit, a first motor, a second motor, and a setpoint memory are connected;

[0036] Figure 3 A side view of a ground vehicle according to Figure 1 with a loaded load and an inductive sensor with an inherent safety function is shown; and

[0037] Figure 4 is shown as Figure 3Side view of the ground vehicle shown, but having an inductive sensor without an inherent safety function and a laser scanner. Detailed Description

[0038] Figure 1 Top view of a driverless, autonomously operating ground vehicle 1 having a control system 3 and a redundant sensor system 7, the sensor system including a load sensor 6 (azimuth sensor) and a laser scanner 8.

[0039] The ground vehicle 1 proposed here has a loading area 1.1 for the load 2 to be transported (see also Figure 3 and Figure 4 ) and includes at least a control system 3 for controlling and maneuvering the ground vehicle and an evaluation unit 4 (see also Figure 2 ) which can generate or cause a signal for stopping the ground vehicle 1. A detection device 5 (see also Figure 2 ) for recognizing the arrangement of the load 2 is connected to the control system 3, wherein the detection device 5 includes an inductive sensor as the load sensor 6 and 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 the movement, and a third control unit 11 for the safety of the ground vehicle 1. A first motor for the travel movement of the ground vehicle 1 is designated by 12 and a second motor for the height adjustment of the lifting device 14 (see Figure 2 ) by 13. A first rotation sensor (rated speed) is designated by 15 and a second rotation sensor, for example a SIL-2 rotation sensor, by 16.

[0040] Prevention of unsafe states is achieved by the following:

[0041] 1) Recognition that the loaded goods 21 have left a defined position.

[0042] 2) Stopping the ground vehicle 1 safely (directly or automatically).

[0043] Leaving the defined position can be recognized by different sensor concepts:

[0044] a) The position of the load 2 is detected by means of a safety sensor which is monitored by a safety control device.

[0045] b) The position of the load 2 is detected by means of a combination of plural, non-safe sensors, which are monitored by a safety control device. For this purpose, for example, inductive switches and a rear laser scanner 8 can be used. In a specific application scenario, the sliding load 2 is forced to intrude into the warning area or protection area of the laser scanner 8 by mechanical guidance.

[0046] Basic process logic:

[0047] 1) The first control unit 9 transfers the desired driving direction and speed to the second control unit 10.

[0048] 2) The second control unit 10 further transfers the desired driving direction to the third control unit 11, calculates the rated speed and transfers it to the motor.

[0049] 3) The third control unit 11 identifies when the load 2 slides via a) a safe inductive sensor or b) an unsafe sensor and the warning area or protection area of the rear laser scanner 8, and sets the speed to v = 0 mm / s via 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.)

[0050] Figure 2 A block diagram of a control system 3 for the ground vehicle 1 proposed herein is illustrated. The load sensor 6 and the laser scanner 8 are connected to the electronic control system 3 via a data-conducting connection 17 by an evaluation unit 4. The second control unit 10 is connected to the first motor 12 via a first speed sensor 15 (rated speed). The second speed sensor 16 is connected to the third control unit 11. The 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 considered for identifying the positioning of the lifting unit 14. The memory element is denoted by 19.

[0051] Figure 3 Shows a side view of the ground vehicle 1 according to Figure 1 with a loaded load 2, and shows an inductive sensor as the load sensor 6, for example, a "safe" sensor with an inherent safety function. The load sensor 6 is mounted on the back of the front section before the loading area 1.1 of the ground vehicle 1 and is oriented in the direction of the load 2. Here, the load 2 consists of a loaded cargo 21 and a transporter 22, and the cargo 21 can be transported using 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.

[0052] Figure 4 shows a side view of a ground vehicle 1 and a load 2 according to Figure 3 , but having a load sensor 6 in the form of an inductive sensor configuration without an inherent safety function and having a laser scanner 8. The load sensor 6 is mounted on the rearward end of the loading area 1.1. The laser scanner 8 is arranged at the rear end of the ground vehicle 1 and the laser field of view 8.1 is directed in a direction away from the ground vehicle 1. In an embodiment according to Figure 3 and Figure 4 , the load sensor 6 can be an inductive "sliding table detection" sensor (DDS).

[0053] The proposed driverless, autonomously operating ground vehicle 1 (AGV) is preferably used, for example, in factories, warehouses, supermarkets or hospitals. Based on sensors such as the laser scanner 8, the load sensor 6, inductive proximity sensors, ultrasonic sensors and / or 3D cameras, collisions and / or disorientation of persons and / or objects are avoided. It conveys, for example, pallets, boxes, racks, parts or small load carriers (KLT) with or without a transport cart 22 ("sliding table").

[0054] List of reference numerals

[0055] 1 Ground vehicle

[0056] 1.1 Loading area

[0057] 2 Load

[0058] 3 Control system

[0059] 4 Evaluation unit

[0060] 5 Detection device

[0061] 6 Load sensor

[0062] 7 Sensor system

[0063] 8 Laser scanner

[0064] 8.1 Laser field of view

[0065] 9 First control unit

[0066] 10 Second control unit

[0067] 11 Third control unit

[0068] 12 First motor

[0069] 13 Second motor

[0070] 14 Lifting device

[0071] 15 First rotation sensor

[0072] 16 Second rotation sensor

[0073] 17 Connection for transmitting data

[0074] 18 Braking system

[0075] 19 Memory element

[0076] 20.1, 20.2, 20.3 Wheels of ground vehicle

[0077] 21 Loaded goods

[0078] 22 Conveyor vehicle

[0079] 23.1, 23.2 Wheels of conveyor vehicle

[0080] A, B Movement directions

Claims

1. A ground transportation vehicle (1) configured for driverless, autonomous operation, having a loading area (1.1) for a load (2) to be transported, the ground transportation vehicle comprising at least: - A control system (3) for controlling and maneuvering a ground vehicle (1), - An evaluation unit (4) for generating a signal for stopping the ground vehicle (1), wherein a detection device (5) for identifying the arrangement of the load (2) in the loading area (1.1) is connected to the control system (3), and wherein the detection device (5) includes a redundant sensor system (7), wherein the sensor system (7) includes at least one proximity sensor, and wherein the proximity sensor is arranged on the back of the front section in front of the loading area (1.1) 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 driving 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 1, wherein, The proximity sensor has an inherent safety function.

4. The ground transportation vehicle (1) according to any one of claims 1 to 3, wherein, There is a combination consisting of a proximity sensor without an inherent safety function and a laser scanner (8).

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

6. The ground transportation vehicle (1) according to claim 2, wherein, The proximity sensor with a safety function, or the combination consisting of a proximity sensor without a safety function and the laser scanner (8) is connected to the third control unit (11).

7. The ground transportation vehicle (1) according to claim 2, wherein, The second control unit (10) and the third control unit (11) are configured to identify a sliding load (2) and stop the ground vehicle (1).

8. The ground transportation vehicle (1) according to any one of claims 1 to 3, wherein, The evaluation unit (4) is integrated into the control system (3).

9. The ground transportation vehicle (1) according to any one of claims 1 to 3, wherein, The load (2) includes a loaded cargo (21) and / or a transporter (22) for the loaded cargo (21).

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