How to drive an autonomous industrial vehicle

Abstract

The present invention relates to a method for driving an autonomous industrial vehicle (1;1a,1b,1c,1d) that transports a load, wherein a safety field (5,6) is defined and monitored by at least one sensor (2,2a) to detect possible obstacles. Sensor (2) is used to determine the dimensions of the load, and the safety field (5,6) is determined according to the determined dimensions, thereby achieving improved navigation.

Description

Technical Field

[0001] The present invention relates to a method for operating an autonomous industrial vehicle that transports a load. In this method, a safety field is defined, and the safety field is monitored by sensors in order to detect possible obstacles. In this way, efficient navigation and route planning of the vehicle are also made possible.

Background Art

[0002] Vehicles that navigate autonomously always require sensors in order to avoid collisions with obstacles, that is, objects, other vehicles, or people. In this case, the safety field is the contour of the vehicle projected in the traveling direction, that is, the area where there must be no obstacles in order to enable collision-free travel.

[0003] On the one hand, the safety field is continuously monitored during travel, and thereby suddenly appearing obstacles are detected, and collisions are avoided by braking or avoidance operations. On the other hand, the safety field is also considered during route planning, and thereby routes that are too narrow for safe passage due to fixed obstacles there are avoided. In the railway industry, such a safety field is generally also called a building limit.

[0004] For example, in the case of an industrial vehicle such as a forklift used in a warehouse or the like, the required safety field is in most cases defined by the load or its geometric shape / size. This is because this safety field protrudes from the contour of the vehicle itself and is therefore a limiting factor during route planning. Usually, the load is placed on a loading platform such as a pallet. Inside a warehouse, generally, loading platforms of various dimensions are used so that loads of various sizes can be stored and transported economically.

[0005] Conventional autonomous industrial vehicles cannot detect the size and shape of the cargo they are currently transporting. Therefore, when determining the safety field, it is always necessary to use the largest possible loading platform with the maximum permissible load capacity as a reference. However, this means that when planning routes, even in areas that are assumed to be narrow, the vehicle will avoid areas that would be easily passable when transporting small cargo, resulting in unnecessarily long routes. Furthermore, a lack of knowledge about the actual necessary safety field can lead to unnecessary braking and avoidance maneuvers during operation.

[0006] Some industrial vehicles are capable of switching between two safety fields of different sizes, a switch performed by external commands generated based on data about the load. These systems are prone to failure, and incorrect user input and / or inventory management errors can lead to collisions and serious accidents.

[0007] In logistics, loading platforms come in a variety of sizes, shapes, and features. Common examples include pallets, long pallets, reusable containers, containers, boxes, mesh boxes, big bag systems, IBCs, and GLTs. Typically, industrial vehicles, FTSs (unmanned transport systems), or AMRs (autonomous mobile robots) are known to be able to transport loading platforms using two lift forks, one single fork, a lift table, or a modular lift platform. In this case, the lift forks and single forks may have different features in terms of their shape, width, and length. Furthermore, industrial vehicles, FTSs, or AMRs can also be used without lift forks. In this case, the lifting motion of the loading platform is achieved, for example, by lifting a support plate or lift table, or by lifting the entire vehicle that has moved directly beneath the loading platform. [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The objective of this invention is to demonstrate a method that avoids these drawbacks and safety risks, enables safe operation, and optimizes the use of available space for navigation. A further objective is to provide an industrial vehicle that is flexibly and safely drivable and can operate in a manner that maximizes the use of available space. [Means for solving the problem]

[0009] Based on this invention, sensors are used to determine the dimensions of the load, and a safety field is determined according to the determined dimensions. In this way, it is possible to optimally design both the autonomous driving itself, i.e., obstacle avoidance and route planning.

[0010] An important aspect of the present invention is that an industrial vehicle can detect its own required space and navigate accordingly.

[0011] In the simplest case, there are two loading platforms of different sizes, and the method according to the present invention can detect whether the smaller or larger loading platform can be transported, including the cargo.

[0012] A particularly simple method can be achieved by using additional sensors to determine the dimensions of the load based on the dimensions of the loading platform on which the load is placed. The rationale for this approach is that regulations typically stipulate that the outline of the load must not extend beyond the loading platform. Assuming this rule is followed, it is sufficient to determine the size of the loading platform to know at least the maximum lateral dimensions of the load. This, combined with a known maximum height, allows for easy determination of the safety field.

[0013] In a particularly advantageous modification of the present invention, before transporting the load, • A process to detect the width of the loading platform, • The process of inserting a lift fork into a loading platform on which cargo is being loaded, • The process of lifting the loading platform, • A process for detecting the free space beneath the loading platform. These are executed in sequence.

[0014] The first two steps can be performed in the order shown above, or in the reverse order. That is, you can insert the lift forks into the loading platform first, and then detect the width of the loading platform.

[0015] In any case, the detection and identification of the safety field is preferably performed immediately after loading the cargo. At the same time, after the loading platform is lifted, the accuracy of this detection is checked. This is because, for example, an object placed immediately next to the loading platform may be mistakenly identified as part of the loading platform during the initial detection. This object will also be detected in the second detection, even if the loading platform has already been lifted, contrary to the lifted loading platform itself, so the detection error can be recognized and corrected, for example, by repeating the measurement.

[0016] It is advantageous for the safety field to be defined as a cross-section perpendicular to the direction of travel, and the width of the safety field matches the width of the load detected by additional sensors plus a specified safety gap. This makes it easy to identify the minimum requirements for collision-free driving.

[0017] In principle, it is possible for the sensors used to monitor the safety field to be different from the sensors used to determine the width of the load. However, in a particularly efficient variation of the method based on the present invention, the determination of the load width is performed by the same sensor used to monitor the safety field. This means that the same sensor is used for different tasks.

[0018] Preferably, multiple sensors are provided to monitor the safety field. These sensors are mounted, for example, at the front corners of the industrial vehicle in the direction of travel. This industrial vehicle typically has its load located at the rear in the direction of travel, the opposite of a conventional forklift.

[0019] The present invention also includes an industrial vehicle for autonomous transport of loads, which is equipped with at least one sensor for monitoring a safety field. This industrial vehicle is formed, for example, like a forklift.

[0020] According to the present invention, the industrial vehicle is characterized in that a sensor is configured to identify the dimensions of the load and determine a safety field accordingly.

[0021] This sensor may be used as a LiDAR sensor.

[0022] LiDAR (Light Detection and Ranging) allows for precise optical measurements / scanning of the surroundings using a rotating laser. This is a form of three-dimensional or two-dimensional laser scanning. Instead of radio waves like radar, a laser beam is used. The results are displayed as a point cloud showing the high-precision X, Y, and Z coordinates of each measurement point.

[0023] Preferably, in this case, the sensor for monitoring the safety field is configured to scan primarily a horizontal scanning plane during its operation.

[0024] For this application, various types of sensors or detection systems that can provide data for detecting obstacles / objects can be used (such as LIDAR, ultrasonic, radar, 3D cameras, TOF (Time Of Flight) mono / stereo cameras, etc.). In the case of a system that provides images, furthermore, a software module can also evaluate these data to recognize the corresponding obstacles / objects and detect their states and positions. In this case, the analysis of the image data / sensor data and the processing of the detection results can be performed in a software-based manner using conventional algorithms or AI methods (such as neural networks).

[0025] Hereinafter, the present invention will be described in more detail using the embodiments shown in the figures.

Brief Description of the Drawings

[0026] [Figure 1] It is a view of an industrial vehicle according to the present invention of the first modification without a loading platform. [Figure 2] It is a view of the industrial vehicle of FIG. 1 with a small loading platform. [Figure 3] It is a view of the industrial vehicle of FIG. 1 with a large loading platform. [Figure 4] It is a view of an industrial vehicle according to the present invention of the second modification without a loading platform. [Figure 5] It is a view of the industrial vehicle of FIG. 4 with a small loading platform. [Figure 6] It is a view of the industrial vehicle of FIG. 5 with a large loading platform. [Figure 7] It is a view of the industrial vehicle of FIG. 2 in which a safety field is shown. [Figure 8] It is a view of the industrial vehicle of FIG. 3 in which a safety field is shown. [Figure 9] It is a side view of an embodiment of an industrial vehicle according to the present invention. [Figure 10] It is a side view of an embodiment of an industrial vehicle according to the present invention. [Figure 11]This is a side view of an embodiment of an industrial vehicle based on the present invention. [Figure 12] This is a side view of an embodiment of an industrial vehicle based on the present invention. [Modes for carrying out the invention]

[0027] Figures 1-3 show an industrial vehicle 1 according to the present invention, which is a first modification of the present invention. Figures 2 and 3 show the recognition of the widths b1 and b2 of the loading platform 4. The industrial vehicle 1, which is formed as a forklift, is equipped with a chassis 8 and lift forks 3 used to accommodate loads, and sensors 2 are positioned at the two front corners of the industrial vehicle 1. In the normal driving mode, the arrow 7 indicates the direction of travel, so in this industrial vehicle 1, the front is opposite the lift forks 3. This means that the two lift forks 3 are at the rear, and it should be noted that such an industrial vehicle 1 is usually movable in all directions when operated.

[0028] In the case of a small loading platform (Figure 2), the width b of the industrial vehicle 1 exceeds the width b1 of the loading platform 4, so the sensor 2 may not detect the loading platform 4. From this, we obtain information that the width b1 of the loading platform 4, and therefore the width b1 of the load, is smaller than the width b of the industrial vehicle 1, and this information becomes a limiting factor when considering possible obstacles.

[0029] In the case of a large loading platform 4 (Figure 3), in the simplest case, only the presence of a large loading platform 4 is detected, so the well-known dimensions of such a loading platform 4 are referenced as the standard value. However, preferably, the width b2 is measured accurately, so the required passage width can be precisely determined.

[0030] Figures 2 and 3 also show the scan width 9 of the sensor 2 for detecting the dimensions of the loading platform 4. From Figure 2, it can be seen that in the case of a small loading platform 4, its width b1 is smaller than or at most equal to the width b of the industrial vehicle 1, and therefore direct detection is not performed.

[0031] Figures 4-6 are almost identical to Figures 1-3, except that sensor 2 is located at the rear corner of industrial vehicle 1, and an additional sensor 2a facing forward is provided.

[0032] Figures 7 and 8 show the industrial vehicle 1 including the safety field monitored by sensor 2, where their width b3 or b4 corresponds to the width b1 or b2 of the loading platform 4 on each side plus the measured safety distance.

[0033] Figures 9 to 12 show side views of possible embodiments of the industrial vehicle 1 according to the present invention. In this case, starting from the left, Figure 9 shows vehicle 1a with individual short lift forks / lift platform. The second from the left, Figure 10, shows vehicle 1b with a typical lift fork 3 used for conventional pallets, the third, Figure 11, shows lift vehicle 1c with the lift fork 3 raised and a scissor-type lift mechanism underneath, and the last, fourth, Figure 12, shows vehicle 1d with a higher lift load and lift fork, implemented as a free-lift vehicle. A free-lift is a lift with a structure that does not require a lift mechanism below the lift fork, which makes it possible to insert the lift fork into a loading platform that is closed on all sides.

Claims

1. A method for operating an autonomous industrial vehicle (1; 1a, 1b, 1c, 1d) for transporting cargo, wherein a safety field (5, 6) is defined and the safety field (5, 6) is monitored by sensors (2, 2a) to detect possible obstacles, characterized in that a sensor (2) is used to determine the dimensions of the cargo, and the safety field (5, 6) is determined according to the determined dimensions.

2. The method according to claim 1, characterized in that the sensor (2) determines the dimensions of the load based on the dimensions of the loading platform (4) on which the load is placed.

3. Before transporting the aforementioned cargo, A step of detecting the width of the loading platform (4), The process of inserting the lift fork (3) into the loading platform (4) on which the load is placed, The process of lifting the loading platform (4), A step of detecting the free space below the loading platform (4) and The method according to claim 1 or 2, characterized in that the following steps are performed in order.

4. A cross-section perpendicular to the direction of travel (7) is determined for the safety field (5, 6), and the width (b) of the safety field (5, 6) is determined. ３ , b ４ ) is the width (b) of the load (4) detected by the sensor (2). １ , b ２ The method according to any one of claims 1 to 3, characterized in that it matches the result obtained by adding a specified safety interval (s) to ).

5. The width (b) of the aforementioned load １ , b ２ The method according to any one of claims 1 to 4, characterized in that the identification of the safety field (5, 6) is performed by the same sensor (2) as the monitoring of the safety field (5, 6).

6. The method according to any one of claims 1 to 5, characterized in that a plurality of sensors (2, 2a) are provided for monitoring the safety field (5, 6).

7. An industrial vehicle (1; 1a, 1b, 1c, 1d) for autonomous transport of a load, comprising at least one sensor (2, 2a) for monitoring a safety field (5, 6), wherein the sensor (2) is configured to identify the dimensions of the load and determine the safety field (5, 6) accordingly.

8. The industrial vehicle (1; 1a, 1b, 1c, 1d) according to claim 7, characterized in that the sensors (2, 2a) are implemented as LIDAR sensors.

9. The industrial vehicle (1; 1a, 1b, 1c, 1d) according to claim 7 or 8, characterized in that the sensors (2, 2a) for monitoring the safety field (5, 6) primarily scan a horizontal scanning surface.

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