CN112591688A

CN112591688A - Ground transport vehicle provided for operation without driver's voluntary action

Info

Publication number: CN112591688A
Application number: CN202011050300.2A
Authority: CN
Inventors: A·海姆; F·勒特林; R·斯蒂芬
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2019-10-02
Filing date: 2020-09-29
Publication date: 2021-04-02
Also published as: DE102019215169A1

Abstract

The invention relates to a ground transport means (1) provided for driver-less autonomous operation, having a loading area (1.1) for a load (2) to be transported, comprising at least: a control system (3) for controlling and operating the ground conveyance (1); an evaluation unit (4) for generating a signal for stopping the ground conveyance (1), wherein a detection device (5) for detecting the arrangement of the load (2) in the loading region (1.1) is connected to the control system (3), and wherein the detection device (5) comprises a redundant sensor system (7).

Description

Ground transport vehicle provided for operation without driver's voluntary action

Technical Field

The invention relates to a driver-free, autonomous floor-mounted transport (automatic guided transport, AGV) for loads to be transported. The invention is particularly applicable to robotic vehicles for transporting loads. Also included are lift ground transport vehicles and non-stacking lift trucks and combinations thereof.

Background

With the advancement of automation technology, the operation of the load becomes more and more important.

When the ground conveyance lifts the load to be conveyed for conveyance, it must be ensured that the load remains in a fixed position during conveyance, or that slipping of the load does not lead to unsafe conditions. For example, the slipping of the load can be prevented by:

1) form-locking receptacles (locking devices) which are activated after loading and before the vehicle begins to move, or

2) A force-fitting receptacle.

Variant 1) can completely prevent (with a correspondingly correct design) sliding. Variant 2) is based on the normal force of the load and therefore brings about an insecurity due to dynamic forces which are not predictable in all driving situations. Thus, inertial forces acting against the normal force may occur, for example, due to the relief of the ground or at the slope-to-plane transition. If the inertial force is large enough to counteract or at least significantly reduce the normal force, the load will move out of the prescribed position.

Disclosure of Invention

Starting from this, the object of the invention is to provide an industrial truck which is provided for driver-free autonomous operation and which alleviates or even avoids the disadvantages described. In particular, the prevention of unsafe situations caused by slipping of the transported goods should be achieved in a structurally simple manner. This is also to be ensured, in particular, when the conveyed goods are supported on rollers. Furthermore, in the event of a slip, the movement of the ground conveyance should be reliably stopped.

These objects are solved with a ground conveyance according to the independent claims. Further embodiments of the invention are given in the dependent claims. It should be noted that, in particular in connection with the description of the figures, other details and modifications of the invention can be implemented, which can be combined with the features of the claims.

This is facilitated by a ground transport vehicle which is provided for driver-free autonomous operation, has a loading area for a load to be transported and comprises at least:

a control system for controlling and operating the ground conveyance,

an evaluation unit which generates a signal for stopping the ground conveyance,

wherein a detection device for identifying the arrangement of the loads in the loading area is connected to the control system, and wherein the detection device comprises a redundant sensor system.

The advantage of the ground transport means proposed here is that the orientation of the loaded goods is continuously monitored, the movement of the load is recognized and the transport means can be safely stopped so that no damage to surrounding objects occurs. In particular, increased safety is achieved by additionally monitoring the load position. Further advantages are represented by the reduced costs and the elimination of wear (in particular by the elimination of mechanical parts for anchoring loads and associated actuators and the (re) use of existing sensor means) with the same safety as compared to known form-fitting receptacles.

A driver-less ground transport means can be a powered transport means intended for active travel, including any trailer if necessary. For this purpose, the ground vehicle can interact with a guidance system in the ground or in the surroundings, which guidance system specifies the route to be traveled.

"load" refers to an object to be manipulated, including its mass, size, condition, and/or arrangement. The load may consist (only) of load goods. The load may also comprise a load and a transport device for loading the load, such as a transport cart, a pallet, a trolley (Bodenroller) or the like. A "load operation" that can be carried out by a ground conveyance is to be understood as, in particular, lifting, lowering, load transfer and/or load handling.

The control system has as its content an automatic device which controls (for example activates/deactivates) and actuates (optionally monitored by sensors) the industrial truck and its associated devices. The system of the driver-less ground conveyance includes a control system that may be part of and/or separate from the ground conveyance. The control system may comprise a computing unit which is arranged in or on the ground conveyance.

The evaluation unit is preferably connected to the sensor system in an electrically and data-conducting manner and is provided for processing its signals. The evaluation unit is provided in particular for analyzing data of a sensor system of the industrial truck, so that in particular the load can be unambiguously detected or determined with regard to its position/position relative to the loading region of the industrial truck. The position determined in the evaluation unit can be adjusted and/or influenced using predefined (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 conveyance can be influenced by the evaluation unit. The evaluation unit can be a separate (electronic) device, but it can also be part of a control system for controlling the ground transportation vehicle itself. The (at least) one data-conducting connection between the evaluation unit and the controller and the sensor system can be realized by wire or wirelessly.

The detection means are arranged to generate a signal indicative of the loading state and/or a change in the loading state. The signal can be interpreted by the evaluation unit and causes a command to a control system, by means of which the ground conveyance can be stopped by means of the brake system under predetermined operating conditions, in particular before the stationary part (partially) leaves the ground conveyance and/or the load (partially) leaves, in particular the loading area and/or strikes a person. Detection devices for detecting the arrangement of the load, in particular the sliding of the load and/or for positioning the load, are connected to the evaluation unit and/or to the control device.

The detection device comprises at least one redundant sensor system which is designed to be fail-safe. "redundant" in this context means, in particular, that at least 2 (individual and/or, if appropriate, different types) detection means or sensors are present. These detection means or sensors are in particular arranged such that they can carry out their measuring function or signal transmission completely and independently of one another.

Preferably, the control system comprises a control unit for the desired direction of travel and speed, a control unit for the movement and a control unit for the safety of the ground conveyance. 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) are preferably components of the Control system.

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

Preferably, the inductive sensor is a proximity sensor. The inductive sensor is expediently arranged on the rearward end of the industrial truck in the vicinity of the loading region. Inductive sensors can detect loads on the industrial truck, transport carriages ("skid bed, Dolly") on the industrial truck or loads arranged on transport carriages.

Preferably, the inductive sensor has an inherent safety function (so-called "safety" sensor). The inductive security sensor thus provided can be protected against cable breaks, for example, or can carry out a continuous test of its function. Thus, the sensor may comprise at least 2 measuring lines and/or sensor units, so that fault protection exists.

Advantageously, there is a combination of a "simple" inductive sensor and a laser scanner without an inherent safety function. The laser scanner scans a predetermined peripheral area with laser light. 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 optics. The laser light can be deflected by a pivoted deflection mirror. The operating time of the laser from scanner to re-reception is determined and evaluated, wherein the distance to obstacles in the scanning area can be deduced therefrom. An "image" may also be generated having a plurality of detected objects oriented relative to one another. More complex analyses of the surroundings are thus also possible. The sensor system can be arranged such that the inductive sensor (in part) monitors the loading area and the laser scanner (in part) monitors the adjacent surrounding area. In this way, a "redundant" system is also provided.

The laser scanner is preferably arranged at the rear of the industrial truck and is oriented, if appropriate, toward the return travel area.

Expediently, the inductive sensor with safety function or the combination of the inductive sensor without safety function and the laser scanner is connected to a third control unit (SCU).

Preferably, the second control unit and the third control unit are provided for detecting a slipping load and stopping the industrial truck.

Advantageously, the evaluation unit is integrated into the control system.

Preferably, the load comprises a load and/or a transport vehicle for loading the load.

With the ground vehicle proposed here, a sliding load is detected by the travel control and safety control and the vehicle is caused to stop. Alternative 1 provides for a "safe" inductive proximity sensor located at the rear of the loading surface or at the edge of the loading area. Alternative 2 is embodied in evaluating a "simple" inductive proximity sensor located at the rear of the loading surface or at the edge of the loading area in combination with the sensor of the rear laser scanner.

The ground transport vehicle can therefore also be embodied with a system for data processing, which comprises means for carrying out the above-described steps of the method with a redundant control system. In particular, the system is provided to determine a change in the position and/or orientation of the load relative to the loading area, in particular using the evaluation unit, by means of a redundant control system, wherein the (predeterminable) impermissible change is determined, and the travel of the industrial truck is prompted to be stopped (without delay).

As a precautionary measure, it should be noted that elements are generally represented by numbers ("first", "second", …) for purposes of distinction only and no dependency or order of the elements is required to be given in advance. With respect to the sensors, this means that, for example, their installation (fixed, following) and/or position (on the carrier, fixture, etc.) can be freely selected independently of the name or according to the technical environment.

Drawings

The invention and the technical field are explained in detail below with the aid of the figures. Here, the same members are identified by the same reference numerals. The drawings are schematic and are not provided to illustrate scale. The explanations set forth in the individual details with reference to one drawing are extractable and can be freely combined with the explanations from the other drawings or the preceding description, unless other circumstances must be derived or such combinations are explicitly forbidden to the person skilled in the art. Schematically showing:

fig. 1 shows a top view of a driver-less autonomous ground vehicle with a control system and a detection device;

fig. 2 shows a block diagram with a control system to which an inductive sensor, a laser scanner, an evaluation unit, a first motor, a second motor and a setpoint value memory are connected;

FIG. 3 shows a side view of the industrial truck according to FIG. 1 with a loaded load and an inductive sensor with an inherent safety function; and is

Fig. 4 shows a side view of the industrial truck as shown in fig. 3, but with an inductive sensor without an inherent safety function and with a laser scanner.

Detailed Description

Fig. 1 shows a top view of a driverless autonomous industrial truck 1 with a control system 3 and a redundant sensor system 7, which comprises a load sensor 6 (azimuth sensor) and a laser scanner 8.

The industrial truck 1 proposed here has a loading area 1.1 for a load 2 to be transported (see also fig. 3 and 4) and comprises at least a control system 3 for controlling and operating the industrial truck and an evaluation unit 4 (see also fig. 2) which can generate or generate a signal for stopping the industrial truck 1. A detection device 5 (see also fig. 2) for detecting the arrangement of the load 2 is connected to the 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 industrial truck 1. A first motor for the driving movement of the industrial truck 1 is denoted by 12 and a second motor for the height adjustment of the lifting device 14 (see fig. 2) is denoted by 13. The first rotation inductor (nominal rotation speed) is denoted by 15 and the second rotation inductor, e.g. a SIL-2 rotation inductor, is denoted by 16.

Preventing an unsafe condition is achieved by:

1) it is recognized that the load 21 leaves the determined position.

2) The ground transportation vehicle 1 is safely (directly or automatically) stopped.

The departure from a determined location can be identified by different sensor solutions:

a) the position of the load 2 is detected by means of a safety sensor, which is monitored by a safety control device.

b) The position of the load 2 is detected by means of a combination of multiple, non-safety 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 the specific application case, the sliding load 2 is forced into the warning area or the protective area of the laser scanner 8 by mechanical guidance.

Basic flow logic:

1) the first control unit 9 transmits the desired direction of travel and speed to the second control unit 10.

2) The second control unit 10 further transmits the desired direction of travel to the third control unit 11, calculates the nominal rotational speed and transmits it to the motor.

3) The third control unit 11 recognizes when the load 2 slips via a) a safe inductive sensor or b) an unsafe sensor and the alarm or protection area of the rear laser scanner 8 and sets the speed v to 0 mm/s via the second control unit 10. (the nominal speed of the third control unit 11 takes precedence over the desired speed of the first control unit 9.)

Fig. 2 shows a block diagram with a control system 3 for the ground conveyance 1 proposed here. The load sensor 6 and the laser scanner 8 are connected to the electronic control system 3 via the evaluation unit 4 via a data-conducting connection 17. The second control unit 10 is connected to the first motor 12 via a first rotational speed sensor 15 (nominal rotational speed). The second rotational speed sensor 16 is connected to the third control unit 11. The brake system 18 is connected to the control system 3, which can generate a signal to the first motor 12 to stop the industrial truck 1. The brake system 18 can also act on the industrial truck 1 alone or in combination with the first motor 12. Furthermore, a second motor 13 for driving the lifting device 14 is connected to the control system 3. The detection device 5 can likewise be used to detect the position of the lifting unit 14. The memory element is denoted by 19.

Fig. 3 shows a side view of the industrial truck 1 according to fig. 1 with a loaded load 2 and shows an inductive sensor as the load sensor 6, for example a "safety" sensor with an inherent safety function. The load cell 6 is mounted on the rear side of the front section in front of the loading region 1.1 of the industrial truck 1 and is oriented in the direction of the load 2. The load 2 is composed of a load 21 and a transport vehicle 22, and the load 21 can be transported by the transport vehicle. The wheels of the industrial truck 1 are designated 20.1, 20.2 and 20.3. The wheels of the feed carriage 22 are denoted by 23.1 and 23.2.

Fig. 4 shows a side view of the industrial truck 1 and the load 2 according to fig. 3, but with a load sensor 6 in the form of an inductive sensor without an inherent safety function and with a laser scanner 8. The load cell 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 industrial truck 1 and the laser field of view 8.1 is oriented in a direction away from the industrial truck 1. In the embodiment according to fig. 3 and 4, the load sensor 6 may be an inductive "sliding gantry detection" sensor (DDS).

The driver-less autonomous ground transport 1 (AGV) proposed here is preferably used in a factory, warehouse, supermarket or hospital, for example. Based on sensors, such as laser scanners 8, load sensors 6, inductive proximity sensors, ultrasonic sensors and/or 3D cameras, collision and/or disorientation of persons and/or objects is avoided. For example, pallets, boxes, racks, parts or small load-bearing Stands (KLTs) with or without transport carriages 22 ("slide carriages").

List of reference numerals

1 ground transport means

1.1 Loading area

2 load

3 control system

4 evaluation unit

5 detecting device

6 load sensor

7 sensor system

8 laser scanner

8.1 laser field of view

9 first control unit

10 second control unit

11 third control unit

12 first motor

13 second motor

14 lifting device

15 first rotary inductor

16 second rotary inductor

17 connection for conducting data

18 brake system

19 memory element

20.1, 20.2, 20.3 wheels for ground vehicles

21 load goods

22 transport vehicle

23.1, 23.2 wheels of delivery wagon

A. B direction of motion.

Claims

1. An industrial truck (1) provided for driver-less, autonomous operation, having a loading area (1.1) for a load (2) to be transported, comprising at least:

a control system (3) for controlling and manoeuvring the ground conveyance (1),

an evaluation unit (4) for generating a signal for stopping the ground vehicle (1),

wherein a detection device (5) for detecting 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).

2. A ground conveyance (1) according to claim 1, wherein the control system (3) comprises a control unit (9) for a desired direction of travel and speed, a control unit (10) for movement, and a control unit (11) for safety of the ground conveyance (1).

3. An industrial truck (1) as claimed in claim 1 or 2 in which the sensor system (7) comprises at least one inductive sensor.

4. An industrial truck (1) as claimed in claim 3 in which the inductive sensor is a proximity sensor.

5. An industrial truck (1) according to any one of the preceding claims, wherein the inductive sensor is arranged on the rear side of the front section before a loading area (1.1) of the industrial truck (1).

6. An industrial truck (1) as claimed in any preceding claim in which the inductive sensor has an intrinsic safety function.

7. An industrial truck (1) according to any one of the preceding claims, wherein there is a combination of an inductive sensor without an inherent safety function and a laser scanner (8).

8. An industrial truck (1) as claimed in any preceding claim wherein the laser scanner (8) is arranged at the rear of the industrial truck (1).

9. An industrial truck (1) according to any one of the preceding claims, wherein an inductive sensor with safety function, or a combination of an inductive sensor without safety function and a laser scanner (8), is connected to the third control unit (11).

10. An earth-moving vehicle (1) according to any of the preceding claims, wherein the second control unit (10) and the third control unit (11) are provided for identifying a slipping load (2) and stopping the earth-moving vehicle (1).

11. A ground conveyance (1) according to any preceding claim, wherein the evaluation unit (4) is integrated into the control system (3).

12. An industrial truck (1) as claimed in any one of the preceding claims, wherein the load (2) comprises a load (21) and/or a transport carriage (22) for the load (21).