NL1040228C2 - METHOD AND METHOD FOR PLANNING ROUTES FOR A (UNMANNED) VEHICLE BASED ON AREA CONTACTS. - Google Patents

Description

Method and method for planning routes for an (unmanned) vehicle based on area contours

PREFACE

The described invention relates to a method for creating routes so that one or more vehicles can complete these routes entirely or partially independently and / or can perform actions on this route. The vehicle can be any type of vehicle that can move in an indoor or outdoor environment. The invention is particularly suitable for applications where the same route and / or operations must be repeatedly performed with the vehicle. In addition, the invention is particularly suitable for applications where the same area must be machined in different directions. Applications can be diverse, such as mowing grass, spraying crops in agriculture and horticulture and performing area-oriented tasks (such as sweeping) in an industrial or communal environment.

The described invention is realized and applied in a computer program that can be loaded into the memory of a computer (or in an external memory medium), and which consists of (parts of) software with which the steps described in the method can be performed with using a computer. This can be the same computer that controls the vehicle.

The described invention also relates to a system for programming a vehicle to independently perform actions based on information about the desired states stored in a storage medium.

BACKGROUND ART

Autonomously operating (autonomous or unmanned) vehicles are often used to replace manned vehicles in order to achieve savings in labor costs, to work in a human-unfriendly environment or to achieve greater positioning precision. Routes for these vehicles are often predefined. When following a predefined route, the vehicle can operate fully or partially independently. When operating partially independently, the vehicle only takes over part of the tasks of the human driver. In many cases this is following the route or parts thereof. It is possible that the (partially) independently navigating vehicle deviates (temporarily) from this route to avoid obstacles on the route.

Routes are defined by defining points in space in a certain context that together describe a route or parts thereof. Routes are often (semi) automatically generated based on (a set of) points in or near the room in which the vehicle will operate. The generated (parts of the) route is stored in a storage medium. During the (partly) independent execution of the route by the vehicle, the stored route is used to guide the vehicle along this route as precisely as possible.

The method of generating routes described above is sufficient in many cases when the vehicle operates partially independently. Examples of this are control systems on agricultural tractors, for example. A set of points is measured and based on this and, among other things, the working width of the machine, parts of the route are (semi) automatically generated. This often concerns the so-called working passages, the parts of the plot on which an operation is carried out. When driving in the working aisles, the tractor is controlled by a computer system that periodically compares the current position (determined by means of GPS, for example) with the desired position (the route or part of it) and the tractor by changing the position of for example guided the steering wheels along the route. When turning at the headland, the human driver takes control and positions the vehicle for the next pass. The control can then be taken over again by the computer system until the end of the work pass, where the driver takes over the control again, etc.

For vehicles that operate completely independently, a derivative technique of the method described above is often used. The desired behavior of the vehicle, both on and outside the work corridors, is generated in advance on a computer system. For this, use can be made of software and mathematical models of the vehicle. The advantage of this method is that different routes can be defined in a flexible manner based on a good definition of the space in which the vehicle is to operate.

The disadvantage of this method is that defining such a route can be complex and often requires a high level of knowledge and a good spatial insight of the person who generates the routes wholly or partly in computer form. Moreover, a good knowledge of the field is necessary i.v.m. possible obstacles (trees, pylons, trenches, stones and the like) and defining or surveying the terrain can be laborious, especially when the space is complex in shape.

DESCRIPTION OF THE FINDING

The invention relates to a method and / or method for generating routes for manned or unmanned vehicles on the basis of area contours.

The method comprises three phases, namely: 1) the definition of area contours and possibly basic direction, 2) the automated generation (planning) of routes and actions thereon and 3) the manned or unmanned execution of the route and actions. The three phases take place sequentially in the described order.

The described invention is realized and applied in a computer program that can be loaded into the memory of a computer (or in an external memory medium), and which consists of (parts of) software with which the steps described in the method can be performed with using a computer. This can be the same computer that controls the vehicle.

During the first phase, the definition of area contours, both the contour (or contours) of the area to be worked (inner contour) and the contour (or contours) of the surrounding entire working area (outer contour) are determined. Outlines consist of a closed set of geographical coordinates that describe the areas. Capturing the area contours can be done in various ways: via surveying methods or, partly automated, such as with the (unmanned) vehicle itself. If necessary, a basic direction can be determined during phase 1. The basic direction is a geographic direction or vector that serves as the starting direction for the operations or operations that must be performed within the area to be processed.

The contours form the basis for phase 2: the partial or fully automated generation of routes for one or more (unmanned) vehicles. The result of phase 2 is a route. A route is a list of states that includes, but is not limited to, the position and orientation of the vehicle in space. Depending on the design of the vehicle, the condition of the vehicle may also include information regarding the condition of attachments, drive lines and propulsion.

When generating routes, a step-by-step plan is followed in which, based on the inner contour (s), outer contour (s), possibly basic direction and vehicle and user settings, one or more routes can be generated with which the vehicle wholly or partially autonomously covers the area located within the inner contour, can edit. The outer contour (s) are used here to define the entire working area; in other words, all parts of the generated routes must fall within the outer contour (s).

When planning, use is made of, among other things, one or more vehicle parameters, such as turning circle, to generate routes that can subsequently also be realized by the vehicle during playback. User settings such as processing speed are used to let the vehicle perform the processing at the correct speed, for example.

Planning is a process whereby, first and foremost, working lines are generated based on the direction of movement (whether or not relative to the basic direction) over the area to be processed. Based on a chosen work order (user setting), the start and end position and start and end direction are determined for each successive work line. Based on the end position and end direction of the previous work line and the start position and direction of the next work line, lines and curves (these may consist of a series of consecutive straight line segments) are generated using mathematical methods such as, but not limited to, Dubins and / or Reeds-Shepp curves. The working lines and curves are then merged into one route, whether or not via optimization algorithms. The route can be supplemented with one or more turns of the surface to be worked; the inner contour or inner contours serve as the basis for this. In the manner described above, on the basis of the user settings, infinitely many routes can in principle be generated, each time using the same area contours and possibly basic direction.

The generated routes are the basis for phase 3, the playback phase. One of the generated routes is selected by the user or operator and this route is used to make the vehicle manned or (partly) unmanned to perform the route and actions on it. During this phase, the current state of the vehicle is periodically, but not necessarily with a fixed frequency, determined and compared with the associated state (s) recorded in the route. If the current condition deviates from the route, the vehicle can be adjusted by means of actuators so that it follows a route and performs operations that are as close as possible to the planned route and operations.

With the method described, it is possible to have a vehicle (partly) independently travel a route and have operations performed to process an area within a working area. Based on one-off contours defined, infinitely many routes (and machining directions) can be generated for the same area to be machined.

An advantage over the current state of the art is that when creating the route and / or operations, the vehicle itself can be used to define contours and that contouring (and basic direction) can thus be easily performed.

A second advantage over the current state of the art is also that with a limited data set (contours and basic direction) infinitely many routes and machining directions can be generated.

DETAILED DESCRIPTION OF THE FINDING AND HOW IT IS APPLIED PREFERREDLY

The invention can be applied to almost all types and types of vehicles that are used for a wide range of applications and activities. To provide a detailed description of the invention, it is described in an application where unmanned grass is mowed on a golf course. However, the invention can, as mentioned before, be applied in or on various vehicles in applications in, but not limited to, agriculture, green, civil engineering. The method described is almost comparable for these applications and areas of application.

To apply the invention for unmanned grass mowing at golf courses, a mowing machine is or will be provided with sensors, actuators, electronics, a computer system and a positioning system. The computer system processes information from sensors and location and can control actuators with the help of electronic circuits (hardware) and software to enable the machine to perform operations such as driving, steering, accelerating and mowing. To be able to determine the position and orientation of the machine, this application (in the open space) uses satellite positioning (such as GPS) and sensors such as gyroscopes and accelerometers.

In order to allow the machine or vehicle to mow a certain area unmanned, routes to be followed by the machine are calculated on the basis of an inner contour, an outer contour and a basic direction. The inner contour is a series of closed series of geographical points that describe the edge of the surface to be mowed. The outer contour is also a series of points that describe the total working area of the machine. The outer contour serves as an absolute definition; the machine must remain within this area during unmanned mowing. The basic direction for this application is the direction from the tee-off location to the green (direction of play).

Phase 1: Defining contours and direction of play

The contours and direction of play are determined in this application form of the invention with the aid of the automated mowing machine itself. The order of recording is not important. To fix the inside contour, the machine is placed precisely on the edge of the surface to be mowed by a driver. The capture of the inner contour is started via a control panel that is linked to the computer system. The user then drives off the edge of the surface to be mown, manually. At the same time, the computer system stores the position of the machine at regular intervals. This creates a series of points (a contour). When the entire contour has been recorded, the recording of the contour is stopped and closed. In this way the inner contour, a closed contour of the surface to be mowed, is defined.

The method for capturing the outer contour (the overall working area of the machine is almost identical to capturing the inner contour. With the machine a closed contour is manually driven and recorded around the inner contour. When capturing the outer contour, the user has been driven in such a way that the entire working area can and / or may be used by the machine, ie the working area is free of obstacles and / or places where driving should not be allowed.

The direction of play is also determined with the machine itself. To this end, recording of the direction of play is started via the control panel of the computer system and the direction of play is manually driven. This direction is recorded with the help of the computer system. The intention of determining the direction of play is that several surfaces (fairways, greens, etc.), viewed from the direction of play, can be mowed in the same direction.

Phase 2: Planning of routes

After playing direction, inside and outside contour have been determined, mowing routes can be generated based on this, for example, with the computer system on the mowing machine. A mowing route is a series of (geographical) points where parameters are linked to each point, such as travel speed, engine speed, cutting height, etc. In order to generate these mowing routes, the previously described contours and direction of play are loaded into the computer memory. In addition, user and machine parameters are loaded into the computer memory. User parameters include desired travel speeds for mowing and turning, the desired mowing pattern (up and down work passes, skip passes and fill in later, black / white mowing patterns, etc.), the direction of the enclosing mowing round along the contour (clockwise or counterclockwise) and the desired direction of the pattern with respect to the playing direction. Machine parameters include working width, minimum turning circle, maximum speeds and maximum acceleration and deceleration of the vehicle.

The generation or planning of routes takes place automatically with the aid of a computer system. To do this, for example, the following steps are followed: 1) Planning parallel straight lines on which to mow. These are the so-called cutting lines where, during playback, the cutting section of the machine must be switched on. When planning the mowing lines, the desired mowing direction with respect to the playing direction (user parameter) is used. The intersections of the mowing lines with the inner contour determine the start and end points of each mowing line. The mutual distance between these lines is determined on the basis of the set working width of the machine (machine parameter).

2) Extending the mowing lines on both sides by a set distance, but no further than the outer contour. This extension ensures that the machine approaches and leaves the working corridors straight when traveling along the route. The extended mowing lines are called working lines.

3) A mowing route is created, this is empty.

4) Determining a working order based on the desired mowing pattern. For example, with an "up-and-down" pattern, every subsequent working line is driven in the opposite direction. The next working line is added to the mowing route.

5) The automatic generation of curves and / or straight lines to (from now on called curves), in the work order, to move from the previous line to the next work line. For this purpose algorithms such as Dubins and / or Reeds-Shepp can be used. Because in many cases this results in multiple solutions, an optimization is carried out whereby curves that fall outside the working area are eliminated. Turning within the inner contour is undesirable in this application and is only permitted if that is not otherwise possible. That is why the remaining curves are calculated as to how many points fall within the inner contour and the curves with the least number of points within the inner contour are selected. When several curves fall outside the inner contour, the first curve is chosen on which the machine only drives forward. This best curve is added to the mowing route.

6) Steps 4) and 5) are repeated until all working lines and curves are linked to one mowing route. The last point in the mowing route is the end point of the last working line.

7) Depending on the chosen direction of the closing mowing lap, the nearest point along the inner contour is chosen and a curve is generated according to the method of step 5) to move from the last point of the last working line to the first point (and the corresponding direction). ) to come to the final mowing round. This curve is added to the mowing route.

8) Points parallel to the inside contour are added to the mowing route so that the mowing route follows the inside contour in the set direction (clockwise or counterclockwise). After one complete lap, the contour is followed for another adjustable distance so that the machine follows the encircling mowing lap completely more than one complete run. This line is added to the mowing route.

9) Planning the end position and direction. An end point is selected at an adjustable distance from the current end point of the mowing route and at an also adjustable distance perpendicular to the inner contour. It is checked whether this point falls within the outer contour and outside the inner contour, and if this is not the case, a subsequent point is iteratively chosen, also perpendicular to the inner contour, until it falls within the outer contour. Using the method of step 5) a curve is planned to the end point. This is added to the mowing route.

10) The mowing route is recorded on a storage medium.

The mowing route is complete and consists of geographic points (coordinates) with the desired travel speed, the desired engine speed, the desired position of the cutting sections (up / down), etc. The mowing route can contain segments on which the machine must drive forward as segments on which the machine must travel backwards.

The above shows the methodology and method of planning a single route based on user and machine parameters. The planning of multiple mowing routes can be iteratively carried out by the computer system by automatically adjusting one or more settings before planning a mowing route. In this way, virtually infinitely many routes can be generated for the same area to be worked on, based on one direction of play and an inner and outer contour.

Phase 3: Unmanned playback of routes

After one or more mowing routes have been generated, they can or can be played unmanned with a suitable, automated mowing machine. For this purpose, the generated mowing routes from a storage medium are loaded into the computer memory. The user chooses, using a control panel, one of these mowing routes. Information on the control panel is used to manually bring the machine to the starting point of the mowing route. The computer system hereby indicates via the control panel whether the machine is correctly positioned by comparing the position and orientation of the machine with the starting position and orientation of the route. When the machine is positioned correctly, (unmanned) playback of the route is started via the control panel or with the aid of a remote control.

During playback, the current state of the vehicle is periodically, but not necessarily with a fixed frequency, determined and compared with the corresponding state on the route. If the current condition differs from the associated condition on the route, the vehicle can be adjusted by means of actuators so that the machine or vehicle follows a route and performs operations that are as close as possible to the planned route and operations.

At the end of the route, the machine is automatically stopped by the computer system. The route playback is thus completed.

Possible extensions and other embodiments

The above methodology describes only one embodiment of the invention, however, many embodiments are possible. This allows multiple inner or outer contours to be defined to define more complex surfaces. Outlines and / or direction of play can be recorded with other or comparable positioning systems and / or instruments or can be derived from existing maps and / or drawings of a digital or digitized nature (such as shape or CAD files).

When planning the routes, one or more steps can be added or omitted and the order of steps can be changed. Generated routes can also be post-processed, for example to change (driving) speeds afterwards.

However, the basis is that one or more inner and outer contours are used for the automated generation of routes. For this, use is made of machine and user settings.

The route planning could optionally be partially or fully integrated in the playback phase. Parts of the route are planned shortly in advance during playback. This method or variants can not only be used for unmanned mowing at golf courses, but also for example for unmanned tasks and / or operations in agriculture or industry.

Claims (18)

1. A method and / or method for allowing a vehicle or machine to follow a route on a manned or unmanned basis and / or to have operations performed, characterized in that the route and operations are calculated on the basis of a defined contour of the area to be worked ( inner contour) and a contour of the surrounding working area (outer contour), possibly supplemented with a basic direction for the actions to be performed. A method and / or method according to claim 1), characterized in that the route and / or actions are calculated on the basis of a plurality of inner or outer contours. A method and / or method according to the preceding claims, characterized in that the routes are calculated using a computer system on the vehicle itself. A method and / or method according to claims 1) or 2), characterized in that routes are calculated on a computer system, not being the computer system on the vehicle. 5. A method and / or method in which routes are not fully calculated in advance, but characterized in that they are calculated in whole or in part while driving or performing actions. 6. A method and / or method with the characteristic that geographical contours and / or directions are recorded with the aid of the automated vehicle itself. A method and / or method according to claim 6), characterized in that contours and / or directions are recorded with the aid of CAD drawings, maps or other information carriers. A method and / or method according to claim 6), characterized in that contours and / or directions are recorded by measuring points in using supported, drawn or self-driving systems with location determination. 9. A method and / or method, characterized in that a vehicle is driven on the basis of a list of geographical positions with associated actions. A method and / or method according to claim 9), characterized in that the vehicle operates wholly or partly independently, whether or not driven by one or more computer systems. A method and / or method according to one or more of the preceding claims, characterized in that the contours, directions, routes and / or operations are transferred one or more times to an identical or different type of storage medium. A computer program that can be loaded into the internal memory of a computer that consists of software or parts thereof for performing one or more steps according to one or more of the preceding claims. The use of one or more of the method (s) and / or method (s) described in claims 1 to 12 in the open space. The use of one or more of the method (s) and / or method (s) described in claims 1 to 12 in closed space (s), such as buildings or tunnels. The use of one or more of the method (s) and / or method (s) described in claims 1 to 12 for mowing sports grounds, such as golf courses The use of one or more of the method (s) and / or method (s) described in claims 1 to 12 in an agricultural or horticultural application, such as in crop care. The use of one or more of the method (s) and / or method (s) described in claims 1 to 12 for transporting or moving goods and / or persons. The use of one or more of the method (s) and / or method (s) described in claims 1 to 12 for in an industrial or civil application such as sweeping of (parking) areas.