WO2023160765A1

WO2023160765A1 - An obstacle detection system for an autonomous agricultural work vehicle

Info

Publication number: WO2023160765A1
Application number: PCT/DK2023/050029
Authority: WO
Inventors: Tommy Ertbølle Madsen; Morten Christian NISSOV
Original assignee: Agrirobot Aps
Priority date: 2022-02-24
Filing date: 2023-02-22
Publication date: 2023-08-31

Abstract

An obstacle detection system (100) for an autonomous agricultural work vehicle (200) is disclosed. The obstacle detection system comprises: -a first sensor array SA1 comprising one or more position detecting sensors PS; -a second sensor array SA2 comprising one or more movement detection sensors MS; -a control unit CU; wherein said control unit CU is configured for receiving signal outputs SO1 from position detecting sensors PS of said first sensor array SA1 and for receiving signal outputs SO2 from movement sensors MS of said second sensor array SA2; wherein said control unit CU is configured, based on signal outputs SO1 received from sensors PS of the first sensor array SA1, to determine whether an obstacle OBST is present within a first predefined hazard zone HZ1 at least partly surrounding said work vehicle (200) or within a first predefined warning zone WZ1; said first predefined warning zone WZ1 is being present outside said first predetermined hazard zone HZ1, relative to said work vehicle (200); wherein said control unit CU is configured, based on signal outputs SO2 received from sensors MS of the second sensor array SA2, to determine whether an obstacle OBST is moving within a second predefined hazard zone HZ2 at least partly surrounding said work vehicle (200), or whether an obstacle OBST is moving towards the work vehicle (200) within a second predefined warning zone WZ2; said second predefined warning zone WZ2 is being present outside said second predefined hazard zone HZ2, relative to said work vehicle (200); wherein said control unit CU is configured to set a hazard alert, thus indicating a hazard situation, in case presence of an obstacle OBST is detected in said first hazard zone HZ1 by one or more sensors PS of said first sensor array SA1 or in case movement of an obstacle OBST is being detected in said second hazard zone HZ2 by one or more sensors MS of said second sensor array SA2; wherein said control unit CU is configured to set a warning alert, thus indicating a warning situation, in case presence of an obstacle OBST is detected in said first warning zone WZ1 by one or more sensors PS of said first sensor array SA1, or in case movement of an obstacle OBST towards the work vehicle (200) is being detected in said second warning zone WZ2 by one or more sensors MS of said second sensor array SA2; wherein said control unit CU is configured for bringing said autonomous work vehicle (200) to a momentarily halt in case a hazard alert is being set.

Description

An obstacle detection system for an autonomous agricultural work vehicle

Field of the invention

The present invention generally relates to the field of safety in operation of agricultural work vehicles.

More specifically, the present invention relates in a first aspect to an obstacle detection system for an autonomous agricultural work vehicle.

In a second aspect the present invention relates to the use of an obstacle detection system according to the first aspect of the present invention for detection of an obstacle and/or for avoiding collision with an obstacle in an agricultural field during working said agricultural field.

In a third aspect the present invention relates to an autonomous agricultural work vehicle comprising an obstacle detection system according to the first aspect of the present invention.

In a fourth aspect the present invention relates to a use of an autonomous agricultural work vehicle according to the third aspect of the present invention for performing an agricultural work operation in an agricultural field.

In a fifth aspect the present invention relates to a method for detection and avoiding collision with an obstacle in an agricultural field during working said field with an autonomous agricultural work vehicle.

In a sixth aspect, the present invention relates to a computer program product, which when being loaded in a data memory of a computer, is configured to perform part of the steps of the method according to the fifth aspect of the present invention.

Background of the invention

Within agriculture it has been customary for more than fifty years to apply motorized equipment in working an agricultural field. Types of field work where motorized equipment is being used are ploughing of the field, tilling of the field, sowing of seeds, weeding the field, fertilizing the field, spraying the field and harvesting said field. One typical motorized equipment used for working an agricultural field is a tractor being configured to tow or carry various types of work implements.

In recent years various autonomous agricultural work vehicles have been put on the market. Such autonomous vehicles are typically designed with a size smaller than typical agricultural tractors. An autonomous agricultural work vehicle comprises a frame suspending a plurality of wheels and/or caterpillar belts which are coupled to propulsion means for propelling the work vehicle. Additionally, an agricultural work vehicle comprises steering means for steering the work vehicle. Finally, the agricultural work vehicle comprises a control system for controlling the operation of the work agricultural work vehicle.

The control system comprises a data storage for storing information representing a predetermined path to be followed over the agricultural field and the agricultural work vehicle comprises position indicating means, such as a GPS receiver for determining the geographical position of said vehicle.

Based on information relation to the detected actual geographical position of the work vehicle and based on the predetermined path to be followed, the control system of the prior art autonomous vehicle is capable of controlling the work vehicle in such a way that the work vehicle will follow this predetermined path.

Although the prior art types of autonomous agricultural comprises some degree of safety means for detecting and avoiding collisions with obstacles on the field, improved safety systems nevertheless are needed.

It is an objective with the present invention to provide technology relating to improved safety systems to be used with an autonomous agricultural work vehicle.

Brief description of the invention

This objective is fulfilled with the present invention in its various aspects.

Accordingly, the present invention in its first aspect relates to an obstacle detection system 100 for an autonomous agricultural work vehicle 200, wherein said obstacle detection system comprises:

-a first sensor array SAI comprising one or more position detecting sensors PS;

-a second sensor array SA2 comprising one or more movement detection sensors MS;

-a control unit CU ; wherein said control unit CU is configured for receiving signal outputs SOI from position detecting sensors PS of said first sensor array SAI and for receiving signal outputs SO2 from movement sensors MS of said second sensor array SA2; wherein said control unit CU is configured, based on signal outputs SOI received from sensors PS of the first sensor array SAI, to determine whether an obstacle OBST is present within a first predefined hazard zone HZ1 at least partly surrounding said work vehicle 200 or within a first predefined warning zone WZ1; said first predefined warning zone WZ1 is being present outside said first predetermined hazard zone HZ1, relative to said work vehicle 200; wherein said control unit CU is configured, based on signal outputs SO2 received from sensors MS of the second sensor array SA2, to determine whether an obstacle OBST is moving within a second predefined hazard zone HZ2 at least partly surrounding said work vehicle 200 , or whether an obstacle OBST is moving towards the work vehicle 200 within a second predefined warning zone WZ2; said second predefined warning zone WZ2 is being present outside said second predefined hazard zone HZ2, relative to said work vehicle 200; wherein said control unit CU is configured to set a hazard alert, thus indicating a hazard situation, in case presence of an obstacle OBST is detected in said first hazard zone HZ1 by one or more sensors PS of said first sensor array SAI or in case movement of an obstacle OBST is being detected in said second hazard zone HZ2 by one or more sensors MS of said second sensor array SA2; wherein said control unit CU is configured to set a warning alert, thus indicating a warning situation, in case presence of an obstacle OBST is detected in said first warning zone WZ1 by one or more sensors PS of said first sensor array SAI, or in case movement of an obstacle OBST towards the work vehicle 200 is being detected in said second warning zone WZ2 by one or more sensors MS of said second sensor array SA2; wherein said control unit CU is configured for bringing said autonomous work vehicle 200 to a momentarily halt in case a hazard alert is being set.

In a second aspect the present invention provides the use of an obstacle detection system 100 according to the first aspect of the invention in an agricultural work vehicle 200 for detection of an obstacle OBST and/or for avoiding collision with an obstacle OBST in an agricultural field during working said agricultural field.

In a third aspect the present invention relates to an autonomous agricultural work vehicle 200 comprising an obstacle detection system 100 according to the first aspect of the invention.

In a fourth aspect the present invention relates to a use of an autonomous agricultural work vehicle 200 according to according to the third aspect of the invention for performing an agricultural work operation in an agricultural field.

In a fifth aspect the present invention relates to a method for detection and avoiding collision with an obstacle OBST in an agricultural field during working said field with an autonomous agricultural work vehicle; wherein said method comprises the steps of: i) providing said agricultural work vehicle with:

-a first sensor array SAI comprising one or more position detecting sensors DS; -a second sensor array SA2 comprising one or more movement detection sensors MS; ii) receiving signal outputs SOI from sensors of said first sensor array SAI and receiving signal outputs SO2 from said second sensor array SA2; iii) based on signal outputs SOI received from sensors PS of the first sensor array SAI, determine whether an obstacle OBST is present within a first predefined hazard zone HZ1 at least partly surrounding said work vehicle 200 or within a first predefined warning zone WZ1; said first predefined warning zone WZ1 is being present outside said first predetermined hazard zone HZ1, relative to said work vehicle; iv) based on signal outputs SO2 received from sensors MS of the second sensor array SA2, determine whether an obstacle OBST is moving within a second predefined hazard zone HZ2, at least partly surrounding said work vehicle, or whether an obstacle OBST is moving towards the work vehicle within a second predefined warning zone WZ2; said second predefined warning zone WZ2 is being present outside said second predefined hazard zone HZ2, relative to said work vehicle; v) setting a hazard alert in case presence of an obstacle OBST is detected in said first hazard zone HZ1 by one or more sensors PS of said first sensor array SAI or in case movement of an obstacle is being detected in said second hazard zone HZ2 by one or more sensors MS of said second sensor array SA2; vi) setting a warning alert in case presence of an obstacle OBST is detected in said first warning zone WZ1 by one or more sensors PS of said first sensor array SAI, or in case movement of an obstacle OBST towards the work vehicle is being detected in said second warning zone WZ2 by one or more sensors MS of said second sensor array SA2; vii) bringing said autonomous work vehicle to a momentarily halt in case a hazard alert is being set.

In a sixth aspect the present invention relates to a computer program product, which when being loaded in a data memory of a computer, is configured to perform part of the steps of the method of the fifth aspect of the invention.

The present invention in its various aspect provides enhanced safety when operating an autonomous agricultural work vehicle.

This is brought about by providing the obstacle detection system 100 in such a way that it is capable of detecting an obstacle which is stationary of the agricultural field being worked by the agricultural work vehicle, or which is moving, relative to the agricultural work vehicle, across the agricultural field. Examples of stationary obstacle which can detected by the obstacle detection system 100 are: masts, power masts, wind turbines, radio towers, buildings, agricultural work machines, vehicles, trees, bushes, ditches, embankments, fences.

Examples of moving obstacle which can detected by the obstacle detection system 100 are: human beings, animals, such as mammals or birds, agricultural work machines, vehicles, drones.

By detecting an obstacle in vicinity of the agricultural work vehicle a collision of the obstacle with the work vehicle can be avoided. Thereby, injury or even death of a living creature can be avoided and physical damages to the work vehicle itself or any structure making up the obstacle can also be avoided.

Brief description of the figure

Fig. 1 is a diagrammatic representation illustrating the working principle of the present invention.

Fig. 2 is a schematic illustration of an embodiment of the working mode of the obstacle detection system of the first aspect of the present application.

Fig. 3a and 3b are schematic diagrams illustrating the concept of angle of detection of the first sensor array AS1 and the second sensor array AS2.

Fig. 4a - 4o are illustrations showing embodiments of various geometries of obstacle detection areas, relative to an agricultural work vehicle.

Detailed description of the invention

The present invention in its first aspect relates to an obstacle detection system 100 for an autonomous agricultural work vehicle 200, wherein said obstacle detection system comprises:

-a first sensor array SAI comprising one or more position detecting sensors PS;

In the present description and in the appended claims the following definitions shall be adhered to:

The term “normal operation” of an autonomous agricultural work vehicle may be construed to mean that no hazard alert and no warning alert has been set by the control unit CU of the obstacle detection system 100.

The term “warning situation” of an autonomous agricultural work vehicle may be construed to mean that a warning alert has been set by the control unit CU of the obstacle detection system 100. The term “hazard situation” of an autonomous agricultural work vehicle may be construed to mean that a hazard alert has been set by the control unit CU of the obstacle detection system 100.

The term “movement of an obstacle towards the agricultural work vehicle” may be construed to mean that the obstacle and the agricultural work vehicle are performing a relative movement towards each other, where the obstacle is also moving relative to the agricultural field. This term may also be construed to mean that in a situation of “movement of an obstacle towards the agricultural work vehicle”, the distance between the obstacle and the agricultural work vehicle becomes smaller over a specific span of time.

The term “footprint of a work vehicle” may be construed to mean a perpendicular projection of all parts of that vehicle, below height of the axles or of the wheels or caterpillar belts, to a planar surface onto which the wheels or caterpillar belts rest.

It should be noted that within the meaning of the present description and the appended claims, the term “obstacle” shall be construed to mean an object, the presence of which has been detected by one or more of the position detecting sensors and/or the movement of which has been detected by one or more of the movement detecting sensors. In this way, the status of an object being present on the field may change dynamically from one point in time to another point in time. Accordingly, one may consider an object being detected by one or more of the position detecting sensors and/or one or more of the movement detecting sensors to be a potential obstacle which may, over a period of time, retain its status as being an obstacle, or which may, over a period of time, change its status to not any longer being an “obstacle”.

As an example, in case one or more of the position detecting sensors or one or more of the movement detecting sensors detects that a small animal, such as a rabbit or a fox is being present or is moving around within the detection range or within the various hazard zones HZ1,HZ2 and warning zones WZ1,WZ2 of such sensors, that small animal will have the status of being an obstacle. However, in case the small animal chooses to flee to a position outside the detection range of the sensors or to a position outside the various hazard zones HZ1,HZ2 and warning zones WZ1,WZ2 of the sensors, that small animal will no longer have the status of being an obstacle.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU is configured for bringing said autonomous work vehicle 200 to change its speed of movement, such as slowing down or speeding up, in case a warning alert is being set.

Hereby enhanced safety is ensured in that the autonomous work vehicle hereby may react to such a warning situation.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, one or more of the position detecting sensors PS of the first sensor array SAI is independently selected form the group of: a lidar sensor, a stereo camera, a time-of-flight camera, an ultrasonic sensor, a radar sensor, a camera, such as one operating in the visible frequency range or in the NIR range, or a thermal camera or a monochrome camera, or a RGB camera, optionally configured to be used with a 3D sensor.

These type of sensors have proven efficient for the intended purpose.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the number of the position detecting sensors PS of the first sensor array SAI is selected from the ranges of 1 - 100 or more, such as 2 - 95, e.g. 3 - 90, such as 4 - 85, for example 5 - 80, such as 8 - 75, such as 10 - 72, for example 15 - 70, such as 20 - 65, e.g. 25 - 60, such as 30 - 55, for example 35 - 50 or 40 - 45.

Such numbers of sensors PS provide adequate detection sensitivity and angular as well as radial detection ranges.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, one or more of the position detecting sensors PS of the first sensor array SAI is of the type which operates by transmitting a signal and receiving an reflection from a physical object, such as an obstacle OBST, and wherein the position of said physical object is determined on the basis of time-of-flight of the signal path of said signal and optionally also direction of transmittal of said signal.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, one or more of the movement detecting sensors MS of the second sensor array SA2 is of the type which operates by transmitting a signal and receiving a reflection from a physical object, such as an obstacle OBST, and wherein the position of said physical object is determined on the basis of time-of-flight of the signal path of said signal and optionally also direction of transmittal of said signal.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, one or more of the position detecting sensors PS of the first sensor array SAI is of the type which operates by receiving electromagnetic radiation reflected by a physical object, such as visible light or light in the IR-range, through a multiple lens system and wherein a distance to said physical object is being calculated based on trigonometric calculations, such as in the form of a stereo camera.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, one or more of the movement detecting sensors MS of the second sensor array SA2 is of the type which operates by receiving electromagnetic radiation reflected by a physical object, such as visible light or light in the IR-range, through a multiple lens system and wherein a distance to said physical object is being calculated based on trigonometric calculations.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, one or more of the movement detecting sensors MS of the second sensor array SA2 independently is being selected form the group of: a radar-sensor, a stereo camera, a time-of- flight camera, an ultrasonic sensor, a lidar sensor, a camera, such as one operating in the visible frequency range or in the NIR range, or a thermal camera or a monochrome camera, optionally configured to be used with a 3D sensor.

These working modes and types of sensors have proven efficient for the intended purpose.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the number of the movement detecting sensors MS of the second sensor array SA2 is selected from the ranges of 1 - 100 or more, such as 2 - 95, e.g. 3 - 90, such as 4 - 85, for example 5 - 80, such as 8 - 75, such as 10 - 72, for example 15 - 70, such as 20 - 65, e.g. 25 - 60, such as 30 - 55, for example 35 - 50 or 40 - 45.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said signal output SOI from a position detecting sensor PS of said first sensor array SAI is having embedded therein, information relating to a position of an object being detected by said position detecting sensor PS.

Hereby, the agricultural work vehicle 200 may be controlled in a way where collision with such an object will be avoided.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said signal output SO2 from a movement detecting sensor MS of said second sensor array SA2 is having embedded therein, information relating to the movement of an object being detected by said movement detecting sensor MS, such as by utilizing the Doppler effect, or wherein said control unit is configured to utilize two or more time-separated signal outputs from said movement detecting sensor MS to determine a movement of an object detected.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU is configured to provide instructions relating to operation of one or more position detecting sensors PS of the first sensor array SAI relating to the operation thereof.

Hereby, improved detection of potential obstacle will be attained.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU is configured to provide instructions relating to operation of one or more movement detecting sensors MS of the second sensor array SA2 relating to the operation thereof.

Hereby, improved detection of potential obstacle will be attained. In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, each of said one or more movement detection sensors MS of said second sensor array SA2 is/are a sensor capable of detecting position as well as movement of an obstacle.

This enhances the efficiency of such movement detection sensors MS.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU is being configured to set a trespassing alarm, for informing an operator, in case one or more sensors MS of said second sensor array SA2 detect(s) movement of an obstacle OB ST in said agricultural field, and optionally, wherein said control unit CU is being configured to transmit such a trespassing alarm to a central monitoring unit being located at a remote location relative to said obstacle detection system 100, wherein optionally said control unit CU is being configured to transmit to said central monitoring unit, geographical coordinates of said field relating to a position on said field of such a moving obstacle OB ST which is being detected.

Hereby enhanced safety is attained.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU, once a hazard alert has been set, is being configured to reset said hazard alert, once a hazard situation is no longer present, as being determined by means of one or more position detecting sensors PS of said first sensor array SAI and/or one or more movement detection sensors MS of said second sensor array SA2.

Hereby, the agricultural work vehicle will be able to resume its operational status, once the hazard situation is no longer present.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU, once a warning alert has been set, is being configured to reset said warning alert, once a warning situation is no longer present, as being determined by means of one or more position detecting sensors PS of said first sensor array SAI and/or one or more movement detection sensors MS of said second sensor array SA2.

Hereby, the agricultural work vehicle will be able to resume its operational status, once the warning situation is no longer present.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit is being configured to provide an instruction signal to said agricultural work vehicle 200, relating to resuming normal operation, when said hazard alert and/or said warning alert has/have been reset, as the case may be. Hereby, the agricultural work vehicle will resume its operational status, once the hazard or warning situation is no longer present.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU comprises a central processing unit (CPU) for processing signals.

Hereby signals transmitted from the sensors PS and MS may be electronically processed.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU comprises a data storage DS for storing information.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said data storage DS is configured to store information relating to the position and geometry of inner and/or outer boundaries of said first predefined hazard zone HZ1, the position and geometry of inner and/or outer boundaries of said second predefined hazard zone HZ2, the position and geometry of inner and/or outer boundaries of said first predefined warning zone WZ1 and/or the position and geometry of inner and/or outer boundaries of said second predefined warning zone WZ2.

This will aid in the determination of presence of an obstacle within the various zoned HZ1, WZ1, HZ2 and WZ2.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the position and geometry of the inner and/or outer boundaries of said first predefined hazard zone HZ1 and/or the position and geometry of the inner and/or outer boundaries of the first predefined warning zone WZ1 is being defined relative to one or more position detecting sensors PS of said first sensor array SAI, or is being defined relative to a work vehicle 200 with which the obstacle detection system 100 is intended to be used, where the position and orientation of said one or more position detecting sensors PS on said vehicle is being predetermined.

Hereby it is possible to let the various zones WZ1 and HZ1 be stationary relative to the autonomous work vehicle 200.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the position and geometry of the inner and/or outer boundaries of said second predefined hazard zone HZ2 and/or the position and geometry of the inner and/or outer boundaries of the second predefined warning zone WZ2 is being defined relative to one or more movement detecting sensors MS of said second sensor array SA2, or is being defined relative to a work vehicle 200 with which the obstacle detection system 100 is intended to be used, where the position and orientation of said one or more movement detecting sensors MS on said vehicle is being predetermined. Hereby it is possible to let the various zones WZ2 and HZ2 be stationary relative to the autonomous work vehicle 200.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU comprises input means IM, such as in the form of an alphanumerical keyboard, for inputting operational instructions to said control unit CU by a human operator; and/or wherein said control unit comprises display means DIS, such as in the form of a monitor enabling a human operator to gain access to status and operational settings of said control system CU.

This will easy the communication between an operator and the control unit CU.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU comprises input means IM and display means DIS which are in the form of a graphical user interface (GUI).

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the extension, in a longitudinal direction X, of said first predefined hazard zone HZ1 and/or of said second predetermined hazard zone HZ2 independently is selected from the ranges of 0.5 - 70 m or more, such as 1 - 65 m, e.g. 1.5 - 60 m, such as 2 - 55 m, for example 3 - 50 m, such as 4 - 45 m, for example 5 - 40 m, such as 10 - 35 m, e.g. 15 - 30 m or 20 - 25 m.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the extension, in a transversal direction Y, of said first predefined hazard zone HZ1 and/or of said second predefined hazard zone HZ2 independently is selected from the ranges of 0.5 - 50 m or more, such as 1 - 45 m, e.g. 1.5 - 40 m, such as 2 - 35 m, for example 3 - 30 m, such as 4 - 25 m, for example 5 - 20 m, such as 10 - 15 m.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the extension, in a longitudinal direction X, of said first predefined warning zone WZ1 and/or of said second predefined warning zone WZ2 independently is selected from the ranges of 0.7 - 100 m or more, such as 1 - 95 m, e.g. 1.5 - 90 m, such as 2 - 85 m, for example 3 - 80 m, such as 4 - 75 m, for example 5 - 70 m, such as 10 - 65 m, e.g. 15 - 60 m, such as 20 - 55 m, for example 25 - 50 m, such as 30 - 45 m or 35 - 40 m.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the extension, in a transversal direction Y, of said first predefined warning zone WZ1 and/or of said second predefined warning zone WZ2 independently is selected from the ranges 1 - 100 m or more, such as 1.5 - 95 m, e.g. 2 - 90 m, such as 2.5 - 85 m, for example 3 - 80 m, such as 4 - 75 m, for example 5 - 70 m, such as 10 - 65 m, e.g. 15 - 60 m, such as 20 - 55 m, for example 25 - 50 m, such as 30 - 45 m or 35 - 40 m. The above examples of extensions of the various zones HZ1, HZ2, WZ1 and HZ2 have proven adequate for the intended purpose of avoiding collisions with obstacles.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the extension, in a transversal direction Y, of said second predetermined hazard zone HZ2 is being broader than the extension, in a transversal direction Y, of said first predefined hazard zone HZ1; and/or the extension, in a transversal direction Y of said second predefined warning zone WZ2 is being broader than the extension, in a transversal direction Y, of said first predefined warning zone WZ1.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said first predefined hazard zone HZ1 and said first predefined warning zone WZ1 are being complementary, i.e. sharing no common coordinates.

Hereby, may be attained that an obstacle will either be present in said first predefined hazard zone HZ1 or in said first predefined warning zone WZ1, or an obstacle will be present in none of these zones.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said second predefined hazard zone HZ2 and said second predefined warning zone WZ2 are being complementary, i.e. sharing no common coordinates.

Hereby, may be attained that an obstacle will either be present in said first predefined hazard zone HZ2 or in said first predefined warning zone WZ2, or an obstacle will be present in none of these zones.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said first predefined hazard zone HZ1 and/or of said second predetermined hazard zone HZ2 independently fully or partly surrounds said vehicle 200.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said first predefined warning zone WZ1 and/or of said second predetermined warning zone WZ2 independently fully or partly surrounds said vehicle 200.

In case the zones to a large extends surround the work vehicle, enhanced safety against collisions with obstacles is provided.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU comprises a first signal processing unit SPU1 for processing signal outputs SOI received from one or more of the position detecting sensors PS of the first sensor array SAI; and wherein said control unit CU comprises a second signal processing unit SPU2 for processing signal outputs SO2 received from one or more of the movement detecting sensors MS of the second sensor array SA2. In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said first signal processing unit SPU 1 and said second signal processing unit SPU2 are the same unit or are different units, optionally being integrated.

According to these two embodiments signals transmitted from the sensors PS and MS may be electronically processed.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said first signal processing unit SPU 1 is being configured, based on the signal outputs SOI received from one or more of the position detecting sensors PS, to process these signal outputs and determine a position of an obstacle OB ST.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said first signal processing unit SPU1 is configured to, from the signal output SOI to detect a major point cloud representing all the environment detected, and wherein said first signal processing unit SPU1 is configured to recognize, by data filtering, one or more minor point clouds, being part of said major point cloud, wherein one or more of said minor point clouds is/are representing an obstacle OB ST; optionally wherein said first signal processing unit SPU 1 in recognizing said one or more minor point clouds representing an obstacle OBST, is configured to consult a data storage DS having stored therein a set of learning data, wherein said set of learning data comprises representations of minor point clouds associated with an obstacle OBST.

Defining a minor point cloud form a major point cloud has proven efficient in the process of detection of an obstacle.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said one or more minor point clouds relate to signals representing one or more of the following: spatial coordinates, RGB-values, NIR or thermal information.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said minor point cloud is being a subset of said major point cloud in relation to one or more of the following criteria: distance between said points and said sensors PS, horizontal angle of said points to said sensors PS, relative to a forward pointing movement direction of said work vehicle 200, vertical angle of said points to said sensors PS, relative to a forward pointing movement direction of said work vehicle 200; density of said points, intensity values of signals received by said sensors PS, colour values (RGB values) of signals received by said sensors PS.

These criteria have proven efficient when filtering data in order to arrive at the minor point cloud representing the obstacle. In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said first signal processing unit SPU 1 is being configured for utilizing deep learning algorithms and/or artificial intelligence and/or neural networks in the process of detecting a position of an obstacle OB ST.

This enhances efficiency even further.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said second signal processing unit SPU2 is being configured, based on two or more time-separated signal outputs SO2 received from one or more of the movement detecting sensors MS, to process these signal outputs and determine a movement of an obstacle OB ST.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said second signal processing unit SPU2 is configured to, from two or more time- separated signal outputs SO2 to detect a major point cloud representing all the environment detected, and wherein said second signal processing unit SPU2 is configured to recognize, by data filtering, one or more minor point clouds, being part of said major point cloud, wherein one or more of said minor point clouds is/are representing an obstacle OB ST, optionally wherein said second signal processing unit SPU2 in recognizing said one or more minor point clouds representing an obstacle OBST, is configured to consult a data storage DS having stored therein a set of learning data, wherein said set of learning data comprises representations of minor point clouds associated with an obstacle OBST.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU is configured, from the signal output SO2 originating from one or more sensors MS, to detect a point cloud representing an obstacle OBST, wherein said point cloud relate to signals representing one or more of the following: spatial coordinates, RGB-values, NIR or thermal information, radial speed, or RCS (radar cross section); or wherein said control unit CU is configured, from the signal output SOI and/or SO2 originating from one or more sensors PS and/or one or more sensors MS to detect a point cloud representing an obstacle OBST, wherein said point cloud relate to signals representing one or more of the following: spatial coordinates, RGB-values, NIR or thermal information, radial speed, or RCS (radar cross section).

These criteria have proven efficient when filtering data in order to arrive at the minor point cloud representing the obstacle.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said minor point cloud is being a subset of said major point cloud in relation to one or more of the following criteria: distance between said points and said sensors MS, horizontal angle of said points to said sensors MS, relative to a forward pointing movement direction of said work vehicle 200, vertical angle of said points to said sensors MS, relative to a forward pointing movement direction of said work vehicle 200; density of said points, intensity values of signals received by said sensors MS, colour values (RGB values) of signals received by said sensors MS; radial speed of object detected, radar cross-section (RCS), signal-to-noise ratio.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said second signal processing unit SPU2 is being configured for utilizing deep learning algorithms and/or artificial intelligence and/or neural networks in the process of detecting the movement of an obstacle.

This enhances efficiency even further.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU comprises means for adjusting the sensitivity of detecting position and/or movement of an obstacle, thereby allowing to set a threshold limit, relating to size of an obstacle OBST, below which the obstacle is being ignored by said control unit CU.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, said control unit CU is being configured to follow the following algorithm: a) via signal outputs SOI from one or more position detection sensors PS of said first sensor array SAI, detect presence of one or more obstacles OBST, if present, and determine a position of said one or more obstacles OBST; b) with reference to coordinates of said first predefined hazard zone HZ1 and said first predefined warning zone WZ1, determine whether an obstacle OBST detected in step a) is being present in said first predefined hazard zone HZ1 or in said first predefined warning zone WZ1; c) via signal outputs SO2 from one or more movement detection sensors MS of said second sensor array SA2, detect presence of one or more moving obstacles OBST, if present, and determine a position and a direction of movement of said one or more obstacles OBST; d) with reference to coordinates of said second predefined hazard zone HZ2 and said second predefined warning zone WZ2, determine whether an obstacle OBST detected in step c) is being present in said second predefined hazard zone HZ2 or in said second predefined warning zone WZ2; e) set a hazard alert in case, in step b) an obstacle OBST is being detected in said first hazard zone HZ1; or in case in step d) movement of an obstacle OBST is being detected in said second hazard zone HZ2; f) optionally, set a warning alert in case in step b) an obstacle OBST is being detected in said first warning zone WZ1; or in case in step d) movement of an obstacle OBST towards the work vehicle is being detected in said second warning zone WZ2.

This algorithm structurally illustrates an efficient way of operating the control system of the obstacle detection system 100.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the inner boundary of said first warning zone WZ1 and the outer boundary of said first hazard zone HZ1 are being coincidal, such as partly or fully coincidal.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the inner boundary of said second warning zone WZ2 and the outer boundary of said second hazard zone HZ2 are being coincidal, such as partly or fully coincidal.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the geometry and/or size of one or more boundaries of said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 independently or dependently are being static over time, or wherein the geometry and/or size of one or more boundaries of said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 independently or dependently are configured to change dynamically over time according to predetermined criteria, such as depending on coordinates relating to position of the agricultural work vehicle on said agricultural field or on type of movement maneuver being performed by said work vehicle, or the speed of said work vehicle, nature of path at actual position, i.e. depending on whether actual position of the work vehicle is being part of straight-lined segment of path or is being part of curved segment of path.

In case one or more of the zones WZ1, HZ1, WZ2 or HZ2 dynamically change over time, as the work vehicle 200 proceeds through the agricultural field, the magnitude of the zone(s) can be adapted to the nature of the field, or the path to be followed.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the extension in a transversal direction Y of said first hazard zone HZ1 and/or said first warning zone WZ1 is configured for being dynamically reduced when said agricultural work vehicle is moving along a boundary of said agricultural field.

Hereby, enhanced safety against collision is attained.

In one embodiment of the obstacle detection system 100 of the first aspect of the present invention, the extension in a transversal direction Y of said second hazard zone HZ2 and/or said second warning zone WZ2 is configured for being dynamically expanded when said agricultural work vehicle is moving along a boundary of said agricultural field, thereby allowing detecting of an obstacle outside the boundary of said agricultural field.

Hereby, enhanced safety against collision is attained.

The second aspect of the present invention

In a second aspect, the present invention provides the use of an obstacle detection system 100 according to the first aspect of the invention in an agricultural work vehicle 200 for detection of an obstacle OBST and/or for avoiding collision with an obstacle OBST in an agricultural field during working said agricultural field.

In one embodiment of the use according to the second aspect of the present invention the working of said agricultural field relates to one of the following: field scouting, field inspection, ploughing said field, harrowing said field, tilling said field, seeding seeds in said field, planting or transplanting said field, weeding said field, such as mechanically weeding said field, fertilizing said field, spraying said field, pruning crops of said field, irrigation of said field, tedding crops of said field, raking crops of said field, harvesting said field or baling crops of said field.

In all these work situations there will be risk of collision of the autonomous work vehicle with an obstacle.

The third aspect of the present invention

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said one or more of said one or more position detecting sensors PS of said first sensor array SAI is/are being arranged on said vehicle 200 so that unobstructed sensing in an essential horizontal direction is provided.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said one or more of said one or more movement detection sensors MS of said second sensor array SA2 is/are being arranged on said vehicle so that unobstructed sensing in an essential horizontal direction is provided.

As obstacles may need to be observed preferably at least at a few meters distance it is advantageous to make the sensors PS and MS perform the sensing in an essential horizontal direction.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, one or more of said one or more position detecting sensors PS of said first sensor array SAI are being arranged on said agricultural work vehicle, so as to enable position detection in a forward pointing direction, relative to a non-turning, forward driving direction of said vehicle.

Hereby collision with an obstacle, caused by the forward moving movement of the work vehicle 200 can be avoided.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, the angle of the detection area ADA of said first sensor array SAI is selected from the ranges of 0 - 180°, such as 5 - 170°, e.g. 10 - 160°, such as 20 - 150°, for example 30 - 140°, such as 40 - 130°, such as 50 - 120°, for example 60 - 110°, 70 - 100° or 80 - 90°, to the right side and/or to the left side, as measured relative to of a forward pointing longitudinal center line CL of said agricultural work vehicle.

These angular ranges have proven efficient in collision avoidance.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, one or more of said one or more movement detecting sensors MS of said second sensor array SA2 is/are being arranged on either side of said agricultural work vehicle 200 so as to enable movement detection at the right hand side and/or at the left hand side of said vehicle, relative to a non-turning, forward driving direction of said vehicle.

Hereby, detection of obstacles approaching the vehicle 200 from the side thereof is possible.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, the angle of the detection area ADA of said second sensor array SA2 at said right hand side and/or at said left hand side of said work vehicle 200 independently is selected from the angle ranges of 0 - 360°, such as 5 - 350°, such as 10 - 340°, such as 20 - 330° for example 30 - 320°, such as 40 - 310°, such as 50 - 300°, 60 - 290°, for example 70 - 280°, such as 80 - 270°, such as 90 - 260°, for example 100 - 250°, such as 110 - 240°, for example 120 - 230°, such as 130 - 220°, e.g. 140 - 210°, such as 150 - 200°, such as 160 - 190 or 170 - 180°, as measured relative to of a forward pointing longitudinal center line CL of said agricultural work vehicle.

These angular ranges have proven efficient in collision avoidance.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, one or more of said one or more position detecting sensors PS of said first sensor array SAI are being arranged on said agricultural work vehicle 200 so as to enable position detection in a backward pointing direction of said vehicle.

Hereby, detection of obstacles being present behind the vehicle 200 is possible.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, the angle of the detection area ADA of said first sensor array SAI is selected from the angle ranges of 0 - 180°, such as 5 - 170°, e.g. 10 - 160°, such as 20 - 150°, for example 30 - 140°, such as 40 - 130°, such as 50 - 120°, for example 60 - 110°, e.g. 70 - 100° or 80 - 90°, as measured relative to of a backward pointing longitudinal center line CL of said agricultural work vehicle. These angular ranges have proven efficient in collision avoidance.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, one or more of said one or more movement detecting sensors MS of said second sensor array SA2 are being arranged on said agricultural work vehicle so as to enable movement detection in a backward pointing direction, relative to a non-turning, forward driving direction of said vehicle.

Hereby, detection of obstacles being approaching the vehicle 200 from behind is possible.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, the angle of the detection area of said second sensor array SA2 is selected from the angle ranges of 0 - 180°, such as 5 - 170°, e.g. 10 - 160°, such as 20 - 150°, for example 30 - 140°, such as 40 - 130°, such as 50 - 120°, for example 60 - 110°, e.g. 70 - 100° or 80 - 90°, as measured relative to of a backward pointing longitudinal center line CL of said agricultural work vehicle.

These angular ranges have proven efficient in collision avoidance.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, only part of the signal outputs SOI originating from one or more of the position detecting sensors PS of said first sensor array SAI are being subject to being processed by said first signal processing unit SPU1 and/or wherein only part of the signal outputs SO2 originating from one or more of the movement detecting sensors MS of said second sensor array SA2 are being subject to being processed by said second signal processing unit SPU2, wherein said part of the signal outputs SOI and/or said signal outputs SO2 is representing a subset of the angle of detection area DA and/or a subset of the range of detection, as being detected by one or more of the position detecting sensors PS of said first sensor array SAI or as being detected by one or more of the movement detecting sensors MS of said second sensor array SA2, respectively.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said subset is being static over time or is dynamically changing over time.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, the maximum distance between the inner boundary of said first hazard zone HZ1 and the footprint of said agricultural work vehicle 200 is selected from the ranges of: 0 - 10 m, such as 0.1 - 9.5 m, for example 0.2 - 9 m, for example 0.3 - 8.5 m, such as 0.4 - 8 m, such as 0.5 - 7.5 m, for example 0.6 - 7 m, such as 0.7 - 6.5 m, for example 0.8 - 6 m, e.g. 0.9 - 5.5 m, such as 1.0 - 5 m, such as 1.2 - 4.5 m, such as 1.5 - 4 m, for example 2 - 3,5 m or 2.5 - 3 m.

Hereby obstacle detection is possible even at relatively close positions to the work vehicle 200.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, the maximum distance between the inner boundary of said second hazard zone HZ2 and the footprint of said agricultural work vehicle 200 is selected from the ranges of: 0 - 10 m, such as 0.1 - 9.5 m, for example 0.2 - 9 m, for example 0.3 - 8.5 m, such as 0.4 - 8 m, such as 0.5 - 7.5 m, for example 0.6 - 7 m, such as 0.7 - 6.5 m, for example 0.8 - 6 m, e.g. 0.9 - 5.5 m, such as 1.0 - 5 m, such as 1.2 - 4.5 m, such as 1.5 - 4 m, for example 2 - 3,5.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said agricultural work vehicle comprises a frame suspending a plurality of wheels and/or caterpillar belts, wherein said agricultural work vehicle comprises propulsion means for propelling said work vehicle, wherein said agricultural work vehicle comprises steering means for steering said work vehicle, wherein said agricultural work vehicle comprises a control system for controlling the operation of said work vehicle.

Such mechanical design of an autonomous work vehicle has proven efficient.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said control system comprises a data storage for storing information representing a path to be followed over said agricultural field and wherein said agricultural work vehicle comprises position indicating means, such as a satellite-based radio-navigation receiver, such as a GPS receiver for determining the position of said vehicle.

Hereby, the wok vehicle may be programmed to follow a predetermined path on an agricultural field.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said control system of said agricultural work vehicle is configured to control the work operation based on said information representing said path to be followed over said agricultural field and based on said determined position of said vehicle.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said propulsion means is in the form of an electric motor or a combustion engine, such as a petrol engine or a diesel engine.

These types of propulsion have proven efficient for an agricultural work vehicle.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said control unit, prior to a planned turn and/or reverse movement of said work vehicle is configured to employ signal information from sensors PS of said first sensor array SAI and/or to employ signal information from sensors MS of said second sensor array SA2 to identify absolute geographical coordinates on said agricultural field which are free of obstacles OBST, and wherein said control unit CU of said obstacle detection system 100 is configured to transmit to said control system of said work vehicle, information that said absolute geographical coordinates on said agricultural field are constituting a no-obstacle area NOA of the agricultural field which is free of obstacles, in which no-obstacle area NOA a turn and/or a reverse movement of said work vehicle accordingly can be safely performed. In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 are defined relative to said agricultural work vehicle 200 so as to not include an area corresponding to the projection of the contour of said wheels and/or caterpillar belts of said vehicle onto a horizontal plane being level with a lowest point of said the wheels and/or caterpillar belts, depending on the turn orientation, relative to a hypothetical fixed vertical plane cutting through said work vehicle, of one or more of said wheels and/or caterpillar belts of said work vehicle 200.

Hereby, the work vehicle 200 itself, or parts thereof, will not be detected as being an obstacle.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 are defined relative to said agricultural work vehicle 200 so as to not include the position of an implement 300 being carried or towed by said work vehicle.

Hereby, the implement 300 itself, or parts thereof, will not be detected as being an obstacle.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, in case one or more of the position detecting sensors DS of said first sensor array SAI and/or one or more of the movement detecting sensors MS of said second sensor array SA2 detects a potential obstacle in said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 or said second warning zone WZ2, the position of which, relative to said work vehicle 200, corresponds to a position of a wheel or a caterpillar belt of said work vehicle 200, said control unit CU is being configured to ignore received data associated herewith, thereby determining that said potential obstacle is not an obstacle OB ST.

Hereby, the wheels or caterpillar belts of the work vehicle 200 itself will not be detected as being an obstacle.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, in case one or more of the position detecting sensors DS of said first sensor array SAI and/or one or more of the movement detecting sensors MS of said second sensor array SA2 detects a potential obstacle OB ST in said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 or said second warning zone WZ2, the position of which, relative to said work vehicle 200, corresponds to a position of an implement 300 being carried or towed by said work vehicle 200, said control unit is being configured to ignore received data associated herewith, thereby determining that said potential obstacle is not an obstacle OB ST.

In one embodiment of the autonomous agricultural work vehicle 200 of the third aspect of the present invention, said control unit CU is configured for receiving information indicative of a potential obstacle from one or more of the position detecting sensors DS of said first sensor array SAI and/or from one or more of the movement detecting sensors MS of said second sensor array SA2 over a time span TS before that control unit CU determined that said potential obstacle indeed is an obstacle, wherein said time span TS ranges from 20- 5,000 ms, such as 50 - 4,000 ms, for example 75 - 3,000 ms, such as 100 - 2,500 ms, such as 200 - 2,200 ms, such as 300 - 2,000 ms, such as 400 - 1,800 ms, e.g. 500 - 1,600 ms, such as 700 - 1,400 ms, e.g. 800 - 1,200 ms or 900 - 1,000 ms.

Hereby it is possible to reduce the detection of “false positives” in respect of detection of obstacles.

The fourth aspect of the present invention

In one embodiment of the use according to the fourth aspect of the present invention, said agricultural work operation is selected from the group comprising: field scouting, field inspection, ploughing said field, harrowing said field, tilling said field, seeding seeds in said field, planting or transplanting said field, weeding said field, such as mechanically weeding said field, fertilizing said field, spraying said field, pruning crops of said field, irrigation of said field, tedding crops of said field, raking crops of said field, harvesting said field or baling crops of said field.

The fifth aspect of the present invention

In a fifth aspect the present invention relates to a method for detection and avoiding collision with an obstacle OB ST in an agricultural field during working said field with an autonomous agricultural work vehicle; wherein said method comprises the steps of: i) providing said agricultural work vehicle with:

-a first sensor array SAI comprising one or more position detecting sensors DS; -a second sensor array SA2 comprising one or more movement detection sensors MS; ii) receiving signal outputs SOI from sensors of said first sensor array SAI and receiving signal outputs SO2 from said second sensor array SA2; iii) based on signal outputs SOI received from sensors PS of the first sensor array SAI, determine whether an obstacle OB ST is present within a first predefined hazard zone HZ1 at least partly surrounding said work vehicle 200 or within a first predefined warning zone WZ1; said first predefined warning zone WZ1 is being present outside said first predetermined hazard zone HZ1, relative to said work vehicle; iv) based on signal outputs SO2 received from sensors MS of the second sensor array SA2, determine whether an obstacle OBST is moving within a second predefined hazard zone HZ2, at least partly surrounding said work vehicle, or whether an obstacle OBST is moving towards the work vehicle within a second predefined warning zone WZ2; said second predefined warning zone WZ2 is being present outside said second predefined hazard zone HZ2, relative to said work vehicle; v) setting a hazard alert in case presence of an obstacle OBST is detected in said first hazard zone HZ1 by one or more sensors PS of said first sensor array SAI or in case movement of an obstacle is being detected in said second hazard zone HZ2 by one or more sensors MS of said second sensor array SA2; vi) setting a warning alert in case presence of an obstacle OBST is detected in said first warning zone WZ1 by one or more sensors PS of said first sensor array SAI, or in case movement of an obstacle OBST towards the work vehicle is being detected in said second warning zone WZ2 by one or more sensors MS of said second sensor array SA2; vii) bringing said autonomous work vehicle to a momentarily halt in case a hazard alert is being set.

In one embodiment of the method according to the fifth aspect of the present invention, said further comprising the step of: viii) bringing said autonomous work vehicle 200 to change its speed of movement, such as slowing down or speeding up, in case a warning alert is being set.

In one embodiment of the method according to the fifth aspect of the present invention, said autonomous agricultural work vehicle 200 is being provided with an obstacle detection system 100 according to the first aspect of the present invention.

The sixth aspect of the present invention

I order to better explain the present invention in its various aspect we now refer to the drawings, wherein Fig. 1 is a diagrammatic representation illustrating the working principle of the present invention. Fig. 1 shows an agricultural work vehicle 200 located in an agricultural field. The work vehicle 200 is moving in the direction of movement DM as indicated by the arrow. The work vehicle 200 has been equipped with an obstacle detection system 100. The obstacle detection system 100 comprises ten sensors, viz. two position detecting sensors PS sensing a position of an obstacle OBST in a forward pointing direction and two position detecting sensors PS sensing a position of an obstacle OBST in a reward pointing direction along with two movement detecting sensors MS which will sense movement of an obstacle OBST in sideways directions, to the right and to the left, relative to the forward moving direction of the work vehicle, respectable. Finally, the obstacle detection system 100 additionally comprises two movement detecting sensors MS which will sense movement of an obstacle OBST and which are arranged at corners at the front of the vehicle 200 along with two movement detecting sensors MS which will sense movement of an obstacle OBST and which are arranged at corners at the rear end of the vehicle 200.

The four position detecting sensors PS constitutes a first sensor array SAI and the six movement detecting sensors MS constitute a second sensor array SA2.

A control unit CU which is part of the obstacle detection system 100 is configured for receiving signal outputs SOI from position detecting sensors PS of said first sensor array SAI and for receiving signal outputs SO2 from movement detecting sensors MS of said second sensor array SA2.

The control unit has been preloaded with information relating to the location, relative to said work vehicle, of a first predefined hazard zone HZ1 surrounding the work vehicle 200 and a first predefined warning zone WZ1. The first predefined warning zone WZ1 is being present outside the first predetermined hazard zone HZ1

Likewise, the control unit has been preloaded with information relating to the location, relative to said work vehicle, of a second predefined hazard zone HZ2 surrounding the work vehicle 200 and a second predefined warning zone WZ2. The second predefined warning zone WZ2 is being present outside the second predetermined hazard zone HZ2.

It should be noted that in general the first predefined hazard zone HZ1, the first predefined warning zone WZ1, the second predetermined hazard zone HZ2 and the second predefined warning zone WZ2 are defined relative to the sensors of the first sensor array SAI and the second sensor array SA2; or relative to the vehicle 200 itself; rather than being defined relative to the surface of the agricultural field.

This may apply in a general sense in relation to the present invention in its various aspects, irrespective of the number of sensors PS and/or MS.

In fig. 1, the relative positions and magnitudes of the work vehicle 200, the first predefined hazard zone HZ1, the first predefined warning zone WZ1, the second predetermined hazard zone HZ2 and the second predefined warning zone WZ2 are not drawn to scale. Additionally, in Fig. 1, the mutual positions and magnitudes the first predefined hazard zone HZ1, the first predefined warning zone WZ1, the second predetermined hazard zone HZ2 and the second predefined warning zone WZ2 have been chosen arbitrarily.

The control unit CU is configured, based on signal outputs SOI received from the position detecting sensors PS of the first sensor array SAI, to determine whether an obstacle OB ST is present within said first predefined hazard zone HZ1 or within said first predefined warning zone WZ1.

Moreover, the control unit CU is configured, based on signal outputs SO2 received from sensors movement detecting sensors MS of the second sensor array SA2, to determine whether an obstacle OBST is moving within said second predefined hazard zone HZ2, or whether an obstacle OBST is moving towards the work vehicle 200 within said second predefined warning zone WZ2.

The control unit CU is configured to set a hazard alert, thus indicating a hazard situation, in case presence of an obstacle OBST is detected in said first hazard zone HZ1 by one or more position detecting sensors PS of the first sensor array SAI or in case movement of an obstacle OBST is being detected in the second hazard zone HZ2 by one or more movement detecting sensors MS of said second sensor array SA2.

Additionally, the control unit CU is configured to set a warning alert, thus indicating a warning situation, in case presence of an obstacle OBST is detected in the first warning zone WZ1 by one or more sensors PS of the first sensor array SAI, or in case movement of an obstacle OBST towards the work vehicle 200 is being detected in the second warning zone WZ2 by one or more sensors MS of the second sensor array SA2.

Finally, the control unit CU is configured for bringing said autonomous work vehicle 200 to a momentarily halt in case a hazard alert is being set.

In fig. 1, a first stationary obstacle OBST1 is being present and detected in the first hazard zone HZ1 and a second obstacle OBST2 is detected as being moving towards the work vehicle 200 within the second hazard zone HZ2.

Each of these situations will make the control unit CU instruct the work vehicle 200 to stop moving.

Also shown in fig. 1 is the directions longitudinal direction X and the transversal direction Y of the four zones HZ1, WZ1, HZ2 and WZ2, respectively.

Fig. 2 is a schematic illustration of an embodiment of the working mode of the obstacle detection system of the first aspect of the present application. As seen the obstacle detection system comprises two position detection sensors PS making up a first sensor array SAI, four movement detection sensors MS making up a second sensor array SA2. Additionally, the system 100 comprises a control unit CU.

The control unit CU receives signal outputs SOI from the position detecting sensors PS of said first sensor array SAI and signal outputs SO2 from the movement detecting sensors MS of said second sensor array SA2. These signal outputs SAI and SA2 are being transmitted to an integrated unit comprising a first signal processing unit SPU1 and a second signal processing unit SPU2.

The first signal processing unit SPU1 is being configured, based on the signal outputs SOI received from the position detecting sensors PS, to process these signal outputs and determine a position of an obstacle.

The first signal processing unit SPU1 may be configured to filter the signal outputs SOI from the position detecting sensors PS of said first sensor array SAI.

The first signal processing unit SPU 1 may in its analysis of detection of an obstacle, consult a data storage DS having stored therein a set of learning data, wherein said set of learning data comprises representations of signal outputs associated with detection of an obstacle.

In some embodiments the first signal processing unit SPU1 is utilizing deep learning algorithms and/or artificial intelligence and/or neural networks in the process of detecting of an obstacle.

Likewise, the second signal processing unit SPU2 is being configured, based on the signal outputs SO2 received from the movement detecting sensors MS, to process these signal outputs and determine a movement of an obstacle.

The second signal processing unit SPU2 may be configured to filter the signal outputs SO2 from the movement detecting sensors MS of said first sensor array SA2.

The second signal processing unit SPU2 may in its analysis of detection movement of an obstacle, consult a data storage DS having stored therein a set of learning data, wherein said set of learning data comprises representations of signal outputs associated with detection of a moving obstacle.

In some embodiments the second signal processing unit SPU2 is utilizing deep learning algorithms and/or artificial intelligence and/or neural networks in the process of detecting an obstacle.

Also seen in Fig. 2 is that the control unit CU comprises input means IM, such as in the form of an alphanumerical keyboard for inputting operational instructions to said control unit CU by a human operator. Moreover, the control unit comprises display means DIS, such as in the form of a monitor, enabling a human operator to gain access to status and operational settings of said control system CU. The input means IM and display means DIS may be combined in the form of a graphical user interface (GUI).

Fig. 3a is a schematic diagram illustrating the concept of angle of detection of the first sensor array AS1 and the second sensor array AS2 detecting in a forward pointing and backward pointing direction, respectively, relative to the work vehicle.

Fig. 3a shows that the angle of detection ADA of the sensor array is defined relative to a forward pointing longitudinal center line CL of said agricultural work vehicle, at either side of this center line, and relative to a backward pointing longitudinal center line CL of said agricultural work vehicle, at either side of that center line CL, respectively.

Fig. 3b is a schematic diagram illustrating the concept of angle of detection of the first sensor array AS1 and the second sensor array AS2 detecting in a sideways pointing direction, relative to forward moving direction of the work vehicle.

Fig. 3b shows that the angle of detection ADA of the sensor array, when detecting in a sideways direction to the right, relative to a forward moving direction of movement DM of said work vehicle, is defined as a range of angles ADA = p - a, wherein each of the angles a and P is measured relative to a forward pointing center line CL of the work vehicle.

The same principle applies in relation to defining the angle of detection ADA of the sensor array, when detecting in a sideways direction to the left, relative to a forward moving direction of movement DM of said work vehicle, (not shown in fig. 3b)

Fig. 4a - 4o shows the agricultural work vehicle 200 with or without a working implement 300 moving in a direction of movement DM. In fig. 4a - 4o the angle and direction, relative to the work vehicle 200, of the first hazard zone HZ1, the first warning zone WZ1, the second hazard zone HZ2, and the second warning zone WZ2 are shown.

The detection angle and direction, relative to the work vehicle 200, of the first sensor array SAI and the detection angle and direction, relative to the work vehicle 200, of the second sensor array SA2 are depicted with the various shadings as shown.

It should be understood that the drawings in Fig. 4a - 4o are not drawn to scale and in particular, it is not the intention in Fig. 4a - 4o to illustrate the range, in the sense of distance from the work vehicle 200, of the various zones WZ1, HZ1, WZ2, HZ2.

We now turn to Fig. 4i, 41, 4m, 4n and 4o in order to illustrate certain specially preferred embodiments.

Fig. 4i illustrates a situation in which the work vehicle 200 is moving in a linear movement following the travel path TP from right to left. The control unit CU of the obstacle detection system 100 of the vehicle 200 has been loaded with information relating to the geometry and magnitude of each of the first hazard zone HZ1, the first warning zone WZ1, the second hazard zone HZ2, and the second warning zone WZ2 as shown.

The work vehicle is in this situation approaching a location on the agricultural field where it needs to make a turning maneuver. To this end the control unit CU of the obstacle detection system 100 expands the boundaries of the first hazard zone HZ1, and first warning zone WZ1, in a longitudinal direction X and in a transversal direction Y, so that these zones will have the boundaries HZF and WZF as shown. In a configuration where the expanded boundaries of the first hazard zone HZ1 ’, and first warning zone WZF are defined, the control system, by means of sensors PS of the first sensor array SAI will determine that a no-obstacle area NOA is being present in front of the vehicle and the control unit CU of the obstacle detection system 100 of the vehicle instructs the control system of the work vehicle to perform a turning maneuver by following travel path TP by first taking a right hand turn, subsequently reversing while turning to the reverse left, and finally resume forward movement by following the travel path TP as shown.

Fig. 41 illustrates a situation in which the first hazard zone HZ1 is being defined to be very close to the sides of the work vehicle 200.

In such a situation it may appear that one or more sensors PS or MS of the first sensor array SAI or the second sensor array SA2 may detect one or more of the wheels, when the orientation of a wheel is in a turning mode, and subsequently the control unit CU of the obstacle detection system 100 may determine that a wheel in its turning mode, represents a potential obstacle.

Fig. 41 illustrates that the wheels W, when in a turning mode, extends into the first hazard zone HZ1.

Accordingly, such a situation thus leads to a “false positive” detection of an obstacle.

In order to cope with and improve the working mode of the obstacle detection system 100 in such a situation the control unit CU is configured to dynamically change the inner boundary of the first hazard zone HZ1 and/or the second hazard zone HZ2 so as to follow the contour of the wheels W. This situation is illustrated in Fig. 4m.

The same principle applies in respect of an implement 300 being carried or towed by the work vehicle 200. As illustrated in fig. 4n an exclusion zone EZ is defined, the location of which, relative to the working vehicle, encompasses that implement 300. In such a situation any object detected within the exclusion zone EZ will not be considered as being an obstacle OBST. It should be noted that for the sake of simplicity in Fig. 4n the extension of the various zones HZ1, WZ1, HZ2 and WZ2 have been drawn with a reduced size, compared to a real life practical situation.

Fig. 4o illustrates a situation in which the work vehicle 200 with implement 300 travels along a field boundary. Here, the outer boundary of each of the second hazard zone HZ2 and the second warning zone WZ2 has been dynamically expanded so a to extend outside the field boundary, thereby detecting the obstacle OBST which is a human being who potentially within a short time could chose to trespass and move into the agricultural field, thereby implying risk of injury of that human being and physical damage to the work vehicle.

Working Examples

Example 1: Hardware set-up

An agricultural work vehicle 200 in the form of a traditional four wheeled tractor is provided.

The work vehicle is provided with a first sensor array SAI comprising two position detecting sensors PS which are arranged at a front part of the work vehicle as illustrated in Fig. 1. The mutual distance between the two position detecting sensors PS is 2.0 m. The two position detecting sensors are of the LIDAR type and are the commercially available Ouster OSO.

Additionally, the work vehicle is provided with a second sensor array SA2 comprising four movement detecting sensors MS which are arranged pairwise at a right hand side and at a left hand side of the work vehicle 200 as illustrated in Fig. 1. The mutual distance between the two movement detecting sensors MS at each side of the work vehicle is 2.5 m. The four movement detecting sensors are of RADAR type, and are commercially available as Smartmicro 153.

Moreover, the work vehicle is provided with a control unit CU. The control unit CU comprises an processing unit of the type Nvidia AGX Xavier which is configured to receive input from the two sensors PS and the four sensors MS. The processing unit is coupled to the vehicle’s ECU (electronic control unit), thereby allowing steering, propulsion and breaking control of the vehicle.

Thereby, the control unit CU is configured to receive signal outputs SOI from the two position detecting sensors PS of the first sensor array SAI and is configured to receive signal outputs SO2 from the four movement detecting sensors MS of the second sensor array SA2 as illustrated in Fig. 2, and on the basis of these signal outputs detect potential obstacles OBST.

The control unit CU also comprises a data storage DS and a central processing unit CPU.

Information relating to the position and the extension, relative to the work vehicle, of a of a first predefined hazard zone HZ1, a first predefined warning zone zone WZ1, a second predefined hazard zone HZ2 and a second predefined warning zone WZ2 is loaded onto the data storage of the control unit.

The first hazard zone HZ1 is defined as being fully contained within the first warning zone WZ1, and the second hazard zone HZ2 is defined as being fully contained within the second warning zone WZ2 (see Fig. 1).

The two hazard zones HZ1 and HZ2 and the two warning zones WZ1 and WZ2 are defined symmetrically around and in relation to the agricultural work vehicle 200. The dimensions of these zones are as follows (width x length):

WZ1: 6.5 x 20.0 m;

HZ1: 6.0 x 10.0 m;

WZ2: 10.0 x 20.0 m;

HZ2: 8.0 x 10.0 m.

Based on the signal outputs SOI from the two position detecting sensors PS of the first sensor array SAI and based on the signal outputs SO2 from the four movement detecting sensors MS of the second sensor array SA2, the control unit, during signal processing of these signals, is able to determine whether or not an obstacle OBST is being present within the first predetermined hazard zone HZ1 or within the second predetermined hazard zone HZ2, and is able to determine whether or not an obstacle OBST is moving within the first predetermined warning zone WZ1 or within the second predetermined warning zone WZ2.

The control unit CU is configured to follow the RANSAC method estimating a plane corresponding to the ground surface and ignoring any points that belong to the ground plane. Points above the ground plane defines a major point cloud. Points of this major point cloud are provided to a clustering algorithm that provides one or more minor point clouds representing obstacle(s).

The control unit CU is configured to set a hazard alert, and thereby indicating a hazard situation, in case presence of an obstacle OBST is detected in the first hazard zone HZ1 by one or more sensors PS of said first sensor array SAI or in case movement of an obstacle OBST is being detected in the second hazard zone HZ2 by one or more sensors MS of the second sensor array SA2.

Likewise, the control unit CU is configured to set a warning alert, and thereby indicating a warning situation, in case presence of an obstacle OBST is detected in the first warning zone WZ1 by one or more sensors PS of the first sensor array SAI, or in case movement of an obstacle OBST towards the work vehicle 200 is being detected in the second warning zone WZ2 by one or more sensors MS of the second sensor array SA2.

Finally, the control unit CU is configured for bringing the autonomous work vehicle 200 to a momentarily halt in case a hazard alert is being set.

The agricultural work vehicle is provided with a GPS based Fields2Cover software for defining a desired path to follow, and the vehicle’s auto-steering mechanism is set to make the vehicle follow his desired path.

Example 2: Operating the agricultural work vehicle of Example 1 The work vehicle 200 of Example 1 is brought to an agricultural field having a non-square rectangular shape and a size of 100 x 500 m and an operator brings the work vehicle to start its autonomous operation over the surface of the field in accordance with a predetermined path to be followed. The work vehicle starts operation at one corner of the field and the predetermined path to be followed comprises a serpentine pattern comprising linear segments parallel to the longest side length of the field with 180° turns at the end of each segment. The distance between parallel paths is 6.0 m. The speed of movement of the work vehicle is per default set to 8 km/h.

A plurality of dummy persons are placed at various positions on the field so as to represent obstacles OB ST.

Moreover, a real person is by movement approaching the moving vehicle from the sides thereof so as to represent a moving obstacle.

The experiments confirm that the obstacle detection system works as intended.

It should be understood that all features and achievements discussed above and in the appended claims in relation to one aspect of the present invention and embodiments thereof apply equally well to the other aspects of the present invention and embodiments thereof.

List of figure references

SAI First sensor array

SA2 Second sensor array

PS Position detecting sensor

MS Movement detecting sensor

CU Control unit of obstacle detection system

501 Signal output from a position detecting sensor

502 Signal output from a movement detecting sensor

OBST Obstacle in an agricultural field

OBST1 Obstacle in an agricultural field

OBST2 Obstacle in an agricultural field

HZ1 First predefined hazard zone

HZ 1 ’ Expanded first hazard zone

HZ2 Second predefined hazard zone

WZ1 First predefined warning zone

WZ 1 ’ Expanded first warning zone

WZ2 Second predefined warning zone

DM Direction of movement

DS Data storage

IM Input means

DIS Display means

X Longitudinal direction of zone

Y Transversal direction of zone

SPU 1 Signal processing unit

SPU2 Signal processing unit

ADA Angle of detection area of sensor

CL Longitudinal center line of work vehicle

DA Detection area of sensor array

NOA No-obstacle area of agricultural field W Wheel of work vehicle

TP Turning path

CR Crop row, such as row of grape vines

FB Field boundary B Bush

EZ Exclusion zone

100 Obstacle detection system

200 Autonomous agricultural work vehicle

300 Working implement used by agricultural work vehicle

Claims

1. An obstacle detection system 100 for an autonomous agricultural work vehicle 200, wherein said obstacle detection system comprises:

-a first sensor array SAI comprising one or more position detecting sensors PS;

-a control unit CU; wherein said control unit CU is configured for receiving signal outputs SOI from position detecting sensors PS of said first sensor array SAI and for receiving signal outputs SO2 from movement sensors MS of said second sensor array SA2; wherein said control unit CU is configured, based on signal outputs SOI received from sensors PS of the first sensor array SAI, to determine whether an obstacle OBST is present within a first predefined hazard zone HZ1 at least partly surrounding said work vehicle 200 or within a first predefined warning zone WZ1; said first predefined warning zone WZ1 is being present outside said first predetermined hazard zone HZ1, relative to said work vehicle 200; wherein said control unit CU is configured, based on signal outputs SO2 received from sensors MS of the second sensor array SA2, to determine whether an obstacle OBST is moving within a second predefined hazard zone HZ2 at least partly surrounding said work vehicle 200, or whether an obstacle OBST is moving towards the work vehicle 200 within a second predefined warning zone WZ2; said second predefined warning zone WZ2 is being present outside said second predefined hazard zone HZ2, relative to said work vehicle 200; wherein said control unit CU is configured to set a hazard alert, thus indicating a hazard situation, in case presence of an obstacle OBST is detected in said first hazard zone HZ1 by one or more sensors PS of said first sensor array SAI or in case movement of an obstacle OBST is being detected in said second hazard zone HZ2 by one or more sensors MS of said second sensor array SA2; wherein said control unit CU is configured to set a warning alert, thus indicating a warning situation, in case presence of an obstacle OBST is detected in said first warning zone WZ1 by one or more sensors PS of said first sensor array SAI, or in case movement of an obstacle OBST towards the work vehicle 200 is being detected in said second warning zone WZ2 by one or more sensors MS of said second sensor array SA2; wherein said control unit CU is configured for bringing said autonomous work vehicle 200 to a momentarily halt in case a hazard alert is being set.

2. An obstacle detection system 100 according to claim 1, wherein said control unit CU is configured for bringing said autonomous work vehicle 200 to change its speed of movement, such as slowing down or speeding up, in case a warning alert is being set.

3. An obstacle detection system 100 according to claim 1 or 2, wherein one or more of the position detecting sensors PS of the first sensor array SAI independently is being selected from the group of: a lidar sensor, a stereo camera, a time-of-flight camera, an ultrasonic sensor, a radar sensor, a camera, such as one operating in the visible frequency range or in the NIR range, or a thermal camera or a monochrome camera, or a RGB camera, optionally configured to be used with a 3D sensor.

4. An obstacle detection system 100 according to any of the preceding claims, wherein the number of the position detecting sensors PS of the first sensor array SAI is selected from the ranges of 1 - 100 or more, such as 2 - 95, e.g. 3 - 90, such as 4 - 85, for example 5 - 80, such as 8 - 75, such as 10 - 72, for example 15 - 70, such as 20 - 65, e.g. 25 - 60, such as 30 - 55, for example 35 - 50 or 40 - 45.

5. An obstacle detection system 100 according to any of the preceding claims, wherein one or more of the position detecting sensors PS of the first sensor array SAI is of the type which operates by transmitting a signal and receiving a reflection from a physical object, such as an obstacle OBST, and wherein the position of said physical object is determined on the basis of time-of-flight of the signal path of said signal and optionally also direction of transmittal of said signal.

6. An obstacle detection system 100 according to any of the preceding claims, wherein one or more of the movement detecting sensors MS of the second sensor array SA2 is of the type which operates by transmitting a signal and receiving a reflection from a physical object, such as an obstacle OBST, and wherein the position of said physical object is determined on the basis of time-of-flight of the signal path of said signal and optionally also direction of transmittal of said signal.

7. An obstacle detection system 100 according to any of the preceding claims, wherein one or more of the position detecting sensors PS of the first sensor array SAI is of the type which operates by receiving electromagnetic radiation reflected by a physical object, such as visible light or light in the IR-range, through a multiple lens system and wherein a distance to said physical object is being calculated based on trigonometric calculations, such as in the form of a stereo camera.

8. An obstacle detection system 100 according to any of the preceding claims, wherein one or more of the movement detecting sensors MS of the second sensor array SA2 is of the type which operates by receiving electromagnetic radiation reflected by a physical object, such as visible light or light in the IR-range, through a multiple lens system and wherein a distance to said physical object is being calculated based on trigonometric calculations.

9. An obstacle detection system 100 according to any of the preceding claims, wherein one or more of the movement detecting sensors MS of the second sensor array SA2 independently is being selected from the group of: a radar-sensor, a stereo camera, a time-of-flight camera, an ultrasonic sensor, a lidar sensor, a camera, such as one operating in the visible frequency range or in the NIR range, or a thermal camera or a monochrome camera, or a RGB camera, optionally configured to be used with a 3D sensor.

10. An obstacle detection 100 system according to any of the preceding claims, wherein the number of the movement detecting sensors MS of the second sensor array SA2 is selected from the ranges of 1 - 100 or more, such as 2 - 95, e.g. 3 - 90, such as 4 - 85, for example 5 - 80, such as 8 - 75, such as 10 - 72, for example 15 - 70, such as 20 - 65, e.g. 25 - 60, such as 30 - 55, for example 35 - 50 or 40 - 45.

11. An obstacle detection system 100 according to any of the preceding claims, wherein said signal output SOI from a position detecting sensor PS of said first sensor array SAI is having embedded therein, information relating to a position of an object being detected by said position detecting sensor PS.

12. An obstacle detection system 100 according to any of the preceding claims, wherein said signal output SO2 from a movement detecting sensor MS of said second sensor array SA2 is having embedded therein, information relating to the movement of an object being detected by said movement detecting sensor MS, such as by utilizing the Doppler effect, or wherein said control unit is configured to utilize two or more time-separated signal outputs from said movement detecting sensor MS to determine a movement of an object detected.

13. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU is configured to provide instructions relating to operation of one or more position detecting sensors PS of the first sensor array SAI relating to the operation thereof.

14. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU is configured to provide instructions relating to operation of one or more movement detecting sensors MS of the second sensor array SA2 relating to the operation thereof.

15. An obstacle detection system 100 according to any of the preceding claims, wherein each of said one or more movement detection sensors MS of said second sensor array SA2 is/are a sensor capable of detecting position as well as movement of an obstacle.

16. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU is being configured to set a trespassing alarm, for informing an operator, in case one or more sensors MS of said second sensor array SA2 detect(s) movement of an obstacle OBST in said agricultural field, and optionally, wherein said control unit CU is being configured to transmit such a trespassing alarm to a central monitoring unit being located at a remote location relative to said obstacle detection system 100, wherein optionally said control unit CU is being configured to transmit to said central monitoring unit, geographical coordinates of said field relating to a position on said field of such a moving obstacle OBST which is being detected.

17. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU, once a hazard alert has been set, is being configured to reset said hazard alert, once a hazard situation is no longer present, as being determined by means of one or more position detecting sensors PS of said first sensor array SAI and/or one or more movement detection sensors MS of said second sensor array SA2.

18. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU, once a warning alert has been set, is being configured to reset said warning alert, once a warning situation is no longer present, as being determined by means of one or more position detecting sensors PS of said first sensor array SAI and/or one or more movement detection sensors MS of said second sensor array SA2.

19. An obstacle detection system 100 according to claim 17 or 18, wherein said control unit is being configured to provide an instruction signal to said agricultural work vehicle 200, relating to resuming normal operation, when said hazard alert and/or said warning alert has/have been reset, as the case may be.

20. An obstacle detection system according to any of the preceding claims, wherein said control unit CU comprises a central processing unit (CPU) for processing signals.

21. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU comprises a data storage DS for storing information.

22. An obstacle detection system 100 according to claim 21, wherein said data storage DS is configured to store information relating to the position and geometry of inner and/or outer boundaries of said first predefined hazard zone HZ1, the position and geometry of inner and/or outer boundaries of said second predefined hazard zone HZ2, the position and geometry of inner and/or outer boundaries of said first predefined warning zone WZ1 and/or the position and geometry of inner and/or outer boundaries of said second predefined warning zone WZ2.

23. An obstacle detection system 100 according to claim 22, wherein the position and geometry of the inner and/or outer boundaries of said first predefined hazard zone HZ1 and/or the position and geometry of the inner and/or outer boundaries of the first predefined warning zone WZ1 is being defined relative to one or more position detecting sensors PS of said first sensor array SAI, or is being defined relative to a work vehicle 200 with which the obstacle detection system 100 is intended to be used, where the position and orientation of said one or more position detecting sensors PS on said vehicle is being predetermined.

24. An obstacle detection system 100 according to claim 22 or 23, wherein the position and geometry of the inner and/or outer boundaries of said second predefined hazard zone HZ2 and/or the position and geometry of the inner and/or outer boundaries of the second predefined warning zone WZ2 is being defined relative to one or more movement detecting sensors MS of said second sensor array SA2, or is being defined relative to a work vehicle 200 with which the obstacle detection system 100 is intended to be used, where the position and orientation of said one or more movement detecting sensors MS on said vehicle is being predetermined.

25. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU comprises input means IM, such as in the form of an alphanumerical keyboard, for inputting operational instructions to said control unit CU by a human operator; and/or wherein said control unit comprises display means DIS, such as in the form of a monitor enabling a human operator to gain access to status and operational settings of said control system CU.

26. An obstacle detection system 100 according to claim 25, wherein said control unit CU comprises input means IM and display means DIS which are in the form of a graphical user interface (GUI).

27. An obstacle detection system 100 according to any of the preceding claims, wherein the extension, in a longitudinal direction X, of said first predefined hazard zone HZ1 and/or of said second predetermined hazard zone HZ2 independently is selected from the ranges of 0.5

- 70 m or more, such as 1 - 65 m, e.g. 1.5 - 60 m, such as 2 - 55 m, for example 3 - 50 m, such as 4 - 45 m, for example 5 - 40 m, such as 10 - 35 m, e.g. 15 - 30 m or 20 - 25 m.

28. An obstacle detection system 100 according to any of the preceding claims, wherein the extension, in a transversal direction Y, of said first predefined hazard zone HZ1 and/or of said second predefined hazard zone HZ2 independently is selected from the ranges of 0.5 - 50 m or more, such as 1 - 45 m, e.g. 1.5 - 40 m, such as 2 - 35 m, for example 3 - 30 m, such as 4

- 25 m, for example 5 - 20 m, such as 10 - 15 m.

29. An obstacle detection system 100 according to any of the preceding claims, wherein the extension, in a longitudinal direction X, of said first predefined warning zone WZ1 and/or of said second predefined warning zone WZ2 independently is selected from the ranges of 0.7 - 100 m or more, such as 1 - 95 m, e.g. 1.5 - 90 m, such as 2 - 85 m, for example 3 - 80 m, such as 4 - 75 m, for example 5 - 70 m, such as 10 - 65 m, e.g. 15 - 60 m, such as 20 - 55 m, for example 25 - 50 m, such as 30 - 45 m or 35 - 40 m.

30. An obstacle detection system 100 according to any of the preceding claims, wherein the extension, in a transversal direction Y, of said first predefined warning zone WZ1 and/or of said second predefined warning zone WZ2 independently is selected from the ranges 1 - 100 m or more, such as 1.5 - 95 m, e.g. 2 - 90 m, such as 2.5 - 85 m, for example 3 - 80 m, such as 4 - 75 m, for example 5 - 70 m, such as 10 - 65 m, e.g. 15 - 60 m, such as 20 - 55 m, for example 25 - 50 m, such as 30 - 45 m or 35 - 40 m.

31. An obstacle detection system 100 according to any of the preceding claims, wherein the extension, in a transversal direction Y, of said second predetermined hazard zone HZ2 is being broader than the extension, in a transversal direction Y, of said first predefined hazard zone HZ1; and/or wherein the extension, in a transversal direction Y of said second predefined warning zone WZ2 is being broader than the extension, in a transversal direction Y, of said first predefined warning zone WZ1.

32. An obstacle detection system 100 according to any of the preceding claims, wherein said first predefined hazard zone HZ1 and said first predefined warning zone WZ1 are being complementary, i.e. sharing no common coordinates.

33. An obstacle detection system 100 according to any of the preceding claims, wherein said second predefined hazard zone HZ2 and said second predefined warning zone WZ2 are being complementary, i.e. sharing no common coordinates.

34. An obstacle detection system 100 according to any of the preceding claims, wherein said first predefined hazard zone HZ1 and/or of said second predetermined hazard zone HZ2 independently fully or partly surrounds said vehicle 200.

35. An obstacle detection system 100 according to any of the preceding claims, wherein the said first predefined warning zone WZ1 and/or of said second predetermined warning zone WZ2 independently fully or partly surrounds said vehicle 200.

36. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU comprises a first signal processing unit SPU1 for processing signal outputs SOI received from one or more of the position detecting sensors PS of the first sensor array SAI; and wherein said control unit CU comprises a second signal processing unit SPU2 for processing signal outputs SO2 received from one or more of the movement detecting sensors MS of the second sensor array SA2.

37. An obstacle detection system 100 according to claim 36, wherein said first signal processing unit SPU1 and said second signal processing unit SPU2 are the same unit or are different units, optionally being integrated.

38. An obstacle detection system 100 according to claim 36 or 37, wherein said first signal processing unit SPU1 is being configured, based on the signal outputs SOI received from one or more of the position detecting sensors PS, to process these signal outputs and determine a position of an obstacle OBST.

39. An obstacle detection system 100 according to any of the claims 36 - 38, wherein said first signal processing unit SPU1 is configured to, from the signal output SOI to detect a major point cloud representing all the environment detected, and wherein said first signal processing unit SPU1 is configured to recognize, by data filtering, one or more minor point clouds, being part of said major point cloud, wherein one or more of said minor point clouds is/are representing an obstacle OBST; optionally wherein said first signal processing unit SPU 1 in recognizing said one or more minor point clouds representing an obstacle OBST, is configured to consult a data storage DS having stored therein a set of learning data, wherein said set of learning data comprises representations of minor point clouds associated with an obstacle OBST.

40. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU is configured, from the signal output SOI originating from one or more sensors PS, to detect a point cloud representing an obstacle OBST, wherein said point cloud relate to signals representing one or more of the following: spatial coordinates, RGB-values, NIR or thermal information.

41. An obstacle detection system 100 according to claim 39 or 40, wherein said minor point cloud is being a subset of said major point cloud in relation to one or more of the following criteria: distance between said points and said sensors PS, horizontal angle of said points to said sensors PS, relative to a forward pointing movement direction of said work vehicle 200, vertical angle of said points to said sensors PS, relative to a forward pointing movement direction of said work vehicle 200; density of said points, intensity values of signals received by said sensors PS, colour values (RGB values) of signals received by said sensors PS.

42. An obstacle detection system 100 according to any of the claims 39 - 41, wherein said first signal processing unit SPU 1 is being configured for utilizing deep learning algorithms and/or artificial intelligence and/or neural networks in the process of detecting a position of an obstacle OBST.

43. An obstacle detection system 100 according to claim any of the claims 36 - 42, wherein said second signal processing unit SPU2 is being configured, based on two or more time- separated signal outputs SO2 received from one or more of the movement detecting sensors MS, to process these signal outputs and determine a movement of an obstacle OBST.

44. An obstacle detection system 100 according to any of the claims 36 - 43, wherein said second signal processing unit SPU2 is configured to, from two or more time- separated signal outputs SO2 to detect a major point cloud representing all the environment detected, and wherein said second signal processing unit SPU2 is configured to recognize, by data filtering, one or more minor point clouds, being part of said major point cloud, wherein one or more of said minor point clouds is/are representing an obstacle OB ST, optionally wherein said second signal processing unit SPU2 in recognizing said one or more minor point clouds representing an obstacle OBST, is configured to consult a data storage DS having stored therein a set of learning data, wherein said set of learning data comprises representations of minor point clouds associated with an obstacle OBST.

45. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU is configured, from the signal output SO2 originating from one or more sensors MS, to detect a point cloud representing an obstacle OBST, wherein said point cloud relate to signals representing one or more of the following: spatial coordinates, RGB-values, NIR or thermal information, radial speed, or RCS (radar cross section); or wherein said control unit CU is configured, from the signal output SOI and/or SO2 originating from one or more sensors PS and/or one or more sensors MS to detect a point cloud representing an obstacle OBST, wherein said point cloud relate to signals representing one or more of the following: spatial coordinates, RGB-values, NIR or thermal information, radial speed, intensity of signal received or RCS (radar cross section).

46. An obstacle detection system 100 according to claim 44 or 45, wherein said minor point cloud is being a subset of said major point cloud in relation to one or more of the following criteria: distance between said points and said sensors MS, horizontal angle of said points to said sensors MS, relative to a forward pointing movement direction of said work vehicle 200, vertical angle of said points to said sensors MS, relative to a forward pointing movement direction of said work vehicle 200; density of said points, intensity values of signals received by said sensors MS, colour values (RGB values) of signals received by said sensors MS; radial speed of object detected, radar cross-section (RCS), signal-to-noise ratio.

47. An obstacle detection system 100 according to any of the claims 44 - 46, wherein said second signal processing unit SPU2 is being configured for utilizing deep learning algorithms and/or artificial intelligence and/or neural networks in the process of detecting the movement of an obstacle.

48. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU comprises means for adjusting the sensitivity of detecting position and/or movement of an obstacle, thereby allowing to set a threshold limit, relating to size of an obstacle OBST, below which the obstacle is being ignored by said control unit CU.

49. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU is being configured to follow the following algorithm: a) via signal outputs SOI from one or more position detection sensors PS of said first sensor array SAI, detect presence of one or more obstacles OB ST, if present, and determine a position of said one or more obstacles OB ST; b) with reference to coordinates of said first predefined hazard zone HZ1 and said first predefined warning zone WZ1, determine whether an obstacle OBST detected in step a) is being present in said first predefined hazard zone HZ1 or in said first predefined warning zone WZ1; c) via signal outputs SO2 from one or more movement detection sensors MS of said second sensor array SA2, detect presence of one or more moving obstacles OBST, if present, and determine a position and a direction of movement of said one or more obstacles OBST; d) with reference to coordinates of said second predefined hazard zone HZ2 and said second predefined warning zone WZ2, determine whether an obstacle OBST detected in step c) is being present in said second predefined hazard zone HZ2 or in said second predefined warning zone WZ2; e) set a hazard alert in case, in step b) an obstacle OBST is being detected in said first hazard zone HZ1; or in case in step d) movement of an obstacle OBST is being detected in said second hazard zone HZ2; f) optionally, set a warning alert in case in step b) an obstacle OBST is being detected in said first warning zone WZ1; or in case in step d) movement of an obstacle OBST towards the work vehicle is being detected in said second warning zone WZ2.

50. An obstacle detection system 100 according to any of the preceding claims, wherein the inner boundary of said first warning zone WZ1 and the outer boundary of said first hazard zone HZ1 are being coincidal, such as partly or fully coincidal.

51. An obstacle detection system 100 according to any of the preceding claims, wherein the inner boundary of said second warning zone WZ2 and the outer boundary of said second hazard zone HZ2 are being coincidal, such as partly or fully coincidal.

52. An obstacle detection system 100 according to any of the preceding claims, wherein the geometry and/or size of one or more boundaries of said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 independently or dependently are being static over time, or wherein the geometry and/or size of one or more boundaries of said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 independently or dependently are configured to change dynamically over time according to predetermined criteria, such as depending on coordinates relating to position of the agricultural work vehicle on said agricultural field, such as depending on distance to field boundary /boundaries, or depending on type of movement maneuver being performed by said work vehicle, or the speed of said work vehicle, nature of path at actual position, i.e. depending on whether actual position of the work vehicle is being part of straight-lined segment of path or is being part of curved segment of path.

53. An obstacle detection system 100 according to claim 52, wherein the extension in a transversal direction Y of said first hazard zone HZ1 and/or said first warning zone WZ1 is configured for being dynamically reduced when said agricultural work vehicle is moving along a boundary of said agricultural field.

54. An obstacle detection system 100 according to claim 52 or 53, wherein the extension in a transversal direction Y of said second hazard zone HZ2 and/or said second warning zone WZ2 is configured for being dynamically expanded when said agricultural work vehicle is moving along a boundary of said agricultural field, thereby allowing detecting of an obstacle outside the boundary of said agricultural field.

55. Use of an obstacle detection system 100 according to any of the preceding claims in an agricultural work vehicle 200 for detection of an obstacle OBST and/or for avoiding collision with an obstacle OBST in an agricultural field during working said agricultural field.

56. Use according to claim 55 wherein the working of said agricultural field relates to one of the following: field scouting, field inspection, ploughing said field, harrowing said field, tilling said field, seeding seeds in said field, planting or transplanting said field, weeding said field, such as mechanically weeding said field, fertilizing said field, spraying said field, pruning crops of said field, irrigation of said field, tedding crops of said field, raking crops of said field, harvesting said field or baling crops of said field.

57. An autonomous agricultural work vehicle 200 comprising an obstacle detection system 100 according to any of the claims 1 - 54.

58. An autonomous agricultural work vehicle 200 according to claim 57, wherein said one or more of said one or more position detecting sensors PS of said first sensor array SAI is/are being arranged on said vehicle 200 so that unobstructed sensing in an essential horizontal direction is provided.

59. An autonomous agricultural work vehicle 200 according to claim 57 or 58, wherein said one or more of said one or more movement detection sensors MS of said second sensor array SA2 is/are being arranged on said vehicle so that unobstructed sensing in an essential horizontal direction is provided.

60. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 59, wherein one or more of said one or more position detecting sensors PS of said first sensor array SAI are being arranged on said agricultural work vehicle, so as to enable position detection in a forward pointing direction, relative to a non-turning, forward driving direction of said vehicle.

61. An autonomous agricultural work vehicle 200 according to claim 60, wherein the angle of the detection area ADA of said first sensor array SAI is selected from the ranges of 0 - 180°, such as 5 - 170°, e.g. 10 - 160°, such as 20 - 150°, for example 30 - 140°, such as 40 - 130°, such as 50 - 120°, for example 60 - 110°, 70 - 100° or 80 - 90°, to the right side and/or to the left side, as measured relative to of a forward pointing longitudinal center line CL of said agricultural work vehicle.

62. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 61, wherein one or more of said one or more movement detecting sensors MS of said second sensor array SA2 is/are being arranged on either side of said agricultural work vehicle 200 so as to enable movement detection at the right hand side and/or at the left hand side of said vehicle, relative to a non-turning, forward driving direction of said vehicle.

63. An autonomous agricultural work vehicle 200 according to claim 62, wherein the angle of the detection area ADA of said second sensor array SA2 at said right hand side and/or at said left hand side of said work vehicle 200 independently is selected from the angle ranges of 0 - 360°, such as 5 - 350°, such as 10 - 340°, such as 20 - 330° for example 30 - 320°, such as 40 - 310°, such as 50 - 300°, 60 - 290°, for example 70 - 280°, such as 80 - 270°, such as 90 - 260°, for example 100 - 250°, such as 110 - 240°, for example 120 - 230°, such as 130 - 220°, e.g. 140 - 210°, such as 150 - 200°, such as 160 - 190 or 170 - 180°, as measured relative to of a forward pointing longitudinal center line CL of said agricultural work vehicle.

64. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 63, wherein one or more of said one or more position detecting sensors PS of said first sensor array SAI are being arranged on said agricultural work vehicle 200 so as to enable position detection in a backward pointing direction of said vehicle.

65. An autonomous agricultural work vehicle 200 according to claim 64, wherein the angle of the detection area ADA of said first sensor array SAI is selected from the angle ranges of 0 - 180°, such as 5 - 170°, e.g. 10 - 160°, such as 20 - 150°, for example 30 - 140°, such as 40 - 130°, such as 50 - 120°, for example 60 - 110°, e.g. 70 - 100° or 80 - 90°, as measured relative to of a backward pointing longitudinal center line CL of said agricultural work vehicle.

66. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 65, wherein one or more of said one or more movement detecting sensors MS of said second sensor array SA2 are being arranged on said agricultural work vehicle so as to enable movement detection in a backward pointing direction, relative to a non-turning, forward driving direction of said vehicle.

67. An autonomous agricultural work vehicle according to claim 66, wherein the angle of the detection area of said second sensor array SA2 is selected from the angle ranges of 0 - 180°, such as 5 - 170°, e.g. 10 - 160°, such as 20 - 150°, for example 30 - 140°, such as 40 - 130°, such as 50 - 120°, for example 60 - 110°, e.g. 70 - 100° or 80 - 90°, as measured relative to of a backward pointing longitudinal center line CL of said agricultural work vehicle.

68. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 67, wherein only part of the signal outputs SOI originating from one or more of the position detecting sensors PS of said first sensor array SAI are being subject to being processed by said first signal processing unit SPU1 and/or wherein only part of the signal outputs SO2 originating from one or more of the movement detecting sensors MS of said second sensor array SA2 are being subject to being processed by said second signal processing unit SPU2, wherein said part of the signal outputs SOI and/or said signal outputs SO2 is representing a subset of the angle of detection area DA and/or a subset of the range of detection, as being detected by one or more of the position detecting sensors PS of said first sensor array SAI or as being detected by one or more of the movement detecting sensors MS of said second sensor array SA2, respectively.

69. An autonomous agricultural work vehicle 200 according to claim 68, wherein said subset is being static over time or is dynamically changing over time.

70. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 69, wherein the maximum distance between the inner boundary of said first hazard zone HZ1 and the footprint of said agricultural work vehicle 200 is selected from the ranges of: 0 - 10 m, such as 0.1 - 9.5 m, for example 0.2 - 9 m, for example 0.3 - 8.5 m, such as 0.4 - 8 m, such as 0.5 - 7.5 m, for example 0.6 - 7 m, such as 0.7 - 6.5 m, for example 0.8 - 6 m, e.g. 0.9 - 5.5 m, such as 1.0 - 5 m, such as 1.2 - 4.5 m, such as 1.5 - 4 m, for example 2 - 3,5 m or 2.5 - 3 m.

71. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 70, wherein the maximum distance between the inner boundary of said second hazard zone HZ2 and the footprint of said agricultural work vehicle 200 is selected from the ranges of: 0 - 10 m, such as 0.1 - 9.5 m, for example 0.2 - 9 m, for example 0.3 - 8.5 m, such as 0.4 - 8 m, such as 0.5 - 7.5 m, for example 0.6 - 7 m, such as 0.7 - 6.5 m, for example 0.8 - 6 m, e.g. 0.9 - 5.5 m, such as 1.0 - 5 m, such as 1.2 - 4.5 m, such as 1.5 - 4 m, for example 2 - 3,5

72. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 71, wherein said agricultural work vehicle comprises a frame suspending a plurality of wheels and/or caterpillar belts, wherein said agricultural work vehicle comprises propulsion means for propelling said work vehicle, wherein said agricultural work vehicle comprises steering means for steering said work vehicle, wherein said agricultural work vehicle comprises a control system for controlling the operation of said work vehicle.

73. An autonomous agricultural work vehicle 200 according to claim 72, wherein said control system comprises a data storage for storing information representing a path to be followed over said agricultural field and wherein said agricultural work vehicle comprises position indicating means, such as a satellite-based radio-navigation receiver, such as a GPS receiver for determining the position of said vehicle.

74. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 73, wherein said control system of said agricultural work vehicle is configured to control the work operation based on said information representing said path to be followed over said agricultural field and based on said determined position of said vehicle.

75. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 74, wherein said propulsion means is in the form of an electric motor or a combustion engine, such as a petrol engine or a diesel engine.

76. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 75, wherein said control unit, prior to a planned turn and/or reverse movement of said work vehicle is configured to employ signal information from sensors PS of said first sensor array SAI and/or to employ signal information from sensors MS of said second sensor array SA2 to identify absolute geographical coordinates on said agricultural field which are free of obstacles OBST, and wherein said control unit CU of said obstacle detection system 100 is configured to transmit to said control system of said work vehicle, information that said absolute geographical coordinates on said agricultural field are constituting a no-obstacle area NOA of the agricultural field which is free of obstacles, in which no-obstacle area NOA a turn and/or a reverse movement of said work vehicle accordingly can be safely performed.

77. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 76, wherein said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 are defined relative to said agricultural work vehicle 200 so as to not include an area corresponding to the projection of the contour of the wheels and/or caterpillar belts of said vehicle onto a horizontal plane being level with a lowest point of said wheels and/or caterpillar belts, depending on the turn orientation, relative to a hypothetical fixed vertical plane cutting through said work vehicle, of one or more of said wheels and/or caterpillar belts of said work vehicle 200.

78. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 77, wherein said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 and said second warning zone WZ2 are defined relative to said agricultural work vehicle 200 so as to not include the position of an implement 300 being carried or towed by said work vehicle.

79. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 78, wherein in case one or more of the position detecting sensors DS of said first sensor array SAI and/or one or more of the movement detecting sensors MS of said second sensor array SA2 detects a potential obstacle in said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 or said second warning zone WZ2, the position of which, relative to said work vehicle 200, corresponds to a position of a wheel or a caterpillar belt of said work vehicle 200, said control unit CU is being configured to ignore received data associated herewith, thereby determining that said potential obstacle is not an obstacle OBST.

80. An autonomous agricultural work vehicle 200 according to any of the claims 57 - 79, wherein in case one or more of the position detecting sensors DS of said first sensor array SAI and/or one or more of the movement detecting sensors MS of said second sensor array SA2 detects a potential obstacle OBST in said first hazard zone HZ1, said first warning zone WZ1, said second hazard zone HZ2 or said second warning zone WZ2, the position of which, relative to said work vehicle 200, corresponds to a position of an implement being carried or towed by said work vehicle 200, said control unit is being configured to ignore received data associated herewith, thereby determining that said potential obstacle is not an obstacle OBST.

81. An obstacle detection system 100 according to any of the preceding claims, wherein said control unit CU is configured for receiving information indicative of a potential obstacle from one or more of the position detecting sensors DS of said first sensor array SAI and/or from one or more of the movement detecting sensors MS of said second sensor array SA2 over a time span TS before that control unit CU determined that said potential obstacle indeed is an obstacle, wherein said time span TS ranges from 20- 5,000 ms, such as 50 - 4,000 ms, for example 75 - 3,000 ms, such as 100 - 2,500 ms, such as 200 - 2,200 ms, such as 300 - 2,000 ms, such as 400 - 1,800 ms, e.g. 500 - 1,600 ms, such as 700 - 1,400 ms, e.g. 800 - 1,200 ms or 900 - 1,000 ms.

82. Use of an autonomous agricultural work vehicle 200 according to any of the claims 57 - 81 for performing an agricultural work operation in an agricultural field.

83. Use according to claim 82, wherein said agricultural work operation is selected from the group comprising: field scouting, field inspection, ploughing said field, harrowing said field, tilling said field, seeding seeds in said field, planting or transplanting said field, weeding said field, such as mechanically weeding said field, fertilizing said field, spraying said field, pruning crops of said field, irrigation of said field, tedding crops of said field, raking crops of said field, harvesting said field or baling crops of said field.

84. A method for detection and avoiding collision with an obstacle OBST in an agricultural field during working said field with an autonomous agricultural work vehicle; wherein said method comprises the steps of: i) providing said agricultural work vehicle with:

-a first sensor array SAI comprising one or more position detecting sensors DS;

-a second sensor array SA2 comprising one or more movement detection sensors MS; ii) receiving signal outputs SOI from sensors of said first sensor array SAI and receiving signal outputs SO2 from said second sensor array SA2; iii) based on signal outputs SOI received from sensors PS of the first sensor array SAI, determine whether an obstacle OBST is present within a first predefined hazard zone HZ1 at least partly surrounding said work vehicle 200 or within a first predefined warning zone WZ1; said first predefined warning zone WZ1 is being present outside said first predetermined hazard zone HZ1, relative to said work vehicle; iv) based on signal outputs SO2 received from sensors MS of the second sensor array SA2, determine whether an obstacle OBST is moving within a second predefined hazard zone HZ2, at least partly surrounding said work vehicle, or whether an obstacle OBST is moving towards the work vehicle within a second predefined warning zone WZ2; said second predefined warning zone WZ2 is being present outside said second predefined hazard zone HZ2, relative to said work vehicle; v) setting a hazard alert in case presence of an obstacle OBST is detected in said first hazard zone HZ1 by one or more sensors PS of said first sensor array SAI or in case movement of an obstacle is being detected in said second hazard zone HZ2 by one or more sensors MS of said second sensor array SA2; vi) setting a warning alert in case presence of an obstacle OBST is detected in said first warning zone WZ1 by one or more sensors PS of said first sensor array SAI, or in case movement of an obstacle OBST towards the work vehicle is being detected in said second warning zone WZ2 by one or more sensors MS of said second sensor array SA2; vii) bringing said autonomous work vehicle to a momentarily halt in case a hazard alert is being set.

85. A method according to claim 84 further comprising the step of: viii) bringing said autonomous work vehicle 200 to change its speed of movement, such as slowing down or speeding up, in case a warning alert is being set.

86. A method according to claim 84 or 85, wherein said autonomous agricultural work vehicle 200 is being provided with an obstacle detection system 100 according to any of the claims 1 - 56.

87. A computer program product, which when being loaded in a data memory of a computer, is configured to perform steps ii) - vii) and optionally also step viii) of the method of any of the claims 84 - 86.