FI130507B

FI130507B - Definition system for defining a spraying area for a spraying machine

Info

Publication number: FI130507B
Application number: FI20195286A
Authority: FI
Inventors: Heikki Huttunen; Kalle Määttä
Original assignee: Normet Oy
Priority date: 2019-04-08
Filing date: 2019-04-08
Publication date: 2023-10-13
Also published as: JP2022528677A; EP3953566B1; JP7542553B2; WO2020208305A1; EP3953566C0; AU2020272984A1; EP3953566A4; FI20195286A1; EP3953566A1

Abstract

The application relates to a definition system (100) for defining a spraying area (A1, A2, A3, A4) for a spraying machine (102). The system comprises a spraying boom (104) of the machine, sensors of the boom, and a controller (120) for controlling the boom. A nozzle tip (115) of the boom is configured to contact several contact points (P1, P2, P3, P4, P5, P6) on a surface (104) to be sprayed in order to define boundaries of the area. The sensors obtain location information of each contact point. The controller defines location of the each contact point in a co-ordinate system of the boom on a grounds of the obtained location information so that defined locations of the contact points are used to form the area to be sprayed in the co-ordinatesystem.

Description

DEFINITION SYSTEM FOR DEFINING A SPRAYING AREA FOR A SPRAYING

MACHINE

Technical field

The application relates generally to a definition system for defining a spraying area for a spraying machine.

Background

Concrete is used to reinforce rock structures in mines and tunnels, and it is sprayed as a concrete layer on these structures by means of mobile concrete sprayers.

The concrete sprayers have a movable, telescopic spraying boom that supports a concrete hose through which the wet concrete flows to a nozzle head of the boom.

The nozzle head with a nozzle tip is installed at the end of boom and an operator uses a moving mechanism and a telescopic structure of boom in order to drive the nozzle tip to a desired location, close to a surface, which will be coated by the concrete layer, so that it is possible to direct a concrete spray accurately to this surface.

One solution to make the spraying process more accurate and to decrease the consumption of sprayed concrete is a use of additional scanner for recognizing a shape of a surface of an area to be sprayed. The scanner produces a view from the surface of the area, whereupon the operator can control movements of the nozzle head and tip, and direct the concrete spray on the grounds of the scanner view.

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N Solutions for spraying processes have been disclosed in published patent applica- 8 tions JP 59-132972 and US 2013/0330467 and patent publication US 5,851,580.

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? 25 Summary

Ao c One object of the invention is to withdraw drawbacks of known solutions and to

N present a definition system for a guick definition of a spraying area, which removes > a need for the use of expensive additional scanners, makes the spraying perfor-

N mance more accurate, and takes a gravity-pased bending and use-based wearing of spraying boom into account

One object of the invention is fulfilled by providing the definition system, controller, methods, computer program, and computer-readable medium according to the in- dependent claims.

Embodiments of the invention are specified by the definition system, controller, methods, computer program, and computer-readable medium according to the in- dependent claims.

One definition system for defining a spraying area for a spraying machine com- prises a spraying boom of the machine, sensors of the boom, and a controller for controlling the boom. A nozzle tip of the boom is configured to contact several con- tact points on a surface to be sprayed in order to define boundaries of the area.

The sensors obtain location information of each contact point. The controller de- fines location of the each contact point in a co-ordinate system of the boom on a grounds of the obtained location information so that defined locations of the con- tact points are used to form the area to be sprayed in the co-ordinate system.

One definition method for defining a spraying area by means of the system, which is in accordance with the previous definition system, comprises a step of contact- ing, by the nozzle tip of the spraying boom several contact points on a surface to be sprayed in order to define boundaries of the area. The method also comprises a step of obtaining, by the sensors of the boom, location information of the each — contact point. The method also comprises a step of defining, by the controller of the boom, location of the each contact point in a co-ordinate system of the boom on a grounds of the obtained location information so that defined locations of the contact points are used to form the area to be sprayed in the co-ordinate system. 2 One controller for defining a spraying area comprises a processor part and a data

T 25 transfer part. The data transfer part receives location information of each contact © point to which a nozzle tip of a spraying boom of a spraying machine has contact- oO ed when boundaries of the area has been defined on a surface to be sprayed. The ? processor part defines location of the each contact point in a co-ordinate system of = the boom on a grounds of the received location information so that defined loca-

S 30 tions of contact points are usedto form the area to be sprayed in the co-ordinate io system.

N One definition method for defining a spraying area by means of the controller, which is in accordance with the previous controller, comprises a step of receiving, by the data transfer part of the controller, location information of each contact point to which a nozzle tip of a spraying boom of a spraying machine has contacted when boundaries of the area has been defined on a surface to be sprayed. The method also comprises a step of defining, by the processor part of the controller, location of the each contact point in a co-ordinate system of the boom on a grounds of the received location information so that defined locations of contact points are used to form the area to be sprayed in the co-ordinate system.

One computer program comprises instructions, which, when the program is exe- cuted by the controller, which is in accordance with the previous controller, cause the controller to carry out the steps of the previous definition method. The program comprises code for receiving, by the data transfer part of the controller, location in- formation of each contact point to which a nozzle tip of a spraying boom of a spraying machine has contacted when boundaries of the area has been defined on a surface to be sprayed. The program also comprises code for defining, by the processor part of the controller, location of the each contact point in a co-ordinate — system of the boom on a grounds of the received location information so that de- fined locations of contact points are used to form the area to be sprayed in the co- ordinate system.

One tangible, computer readable medium comprises the computer program, which is In accordance with the previous computer program.

Brief description of the figures

The exemplary embodiments are described with reference to the accompanying figures:

Fig. 1 presents a principle of definition system for defining a spraying area & Fig. 2 presents a flowchart of definition and spraying method o 25 Fig. 3 presents calculated movements of spraying boom during the spraying ? process 3 Fig. 4 presents parts of controller

I a = Detailed description of the figures

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00 io Fig. 1 presents a definition system 100 for defining at least one spraying area A1,

S 30 A2, A3, A4 and for spraying the defined area(s) A1, A2, A3, A4 with concrete by

N means of a spraying machine 102 in order to form a supporting concrete layer on e.g. a surface 104 of a wall and roof (vault) structure of a tunnel profile 106.

The at least one area A1, A2, A3, A4 comprises e.g. one, two, three, four, or more areas.

The machine 102 is e.g. a mobile concrete sprayer that is used in tunnel profiles 106 in underground mining and tunneling. The machine 102 is also capable of spraying other materials, e.g. water or detergents for cleaning surfaces 104, and it is also capable of operating outside the tunnel profiles 106 in other environments for same purposes.

The system 100 comprises a spraying boom 108, e.g. telescopic sprayer boom, that is a part of the machine 102 and attached (installed) to the machine 102 by means of an attachment mechanism 110 so that it is possible to lift and to lower the boom 108, and to rotate (turn around) it by means of its movement mechanism 426 in relation to the attachment mechanism 110.

The boom 108 comprises at least telescopic boom structures 112, 113 and a noz- zle head 114 through which the concrete is sprayed at an end of the telescopic boom structure 113. The nozzle head 114, or actually a nozzle tip 115, is used to make contact to contact points P1, P2, P3, P4, P5, P6 on the surface 104 to be sprayed in order to define boundaries of the area(s) A1, A2, A3, A4.

The contact points P1, P2, P3, P4, P5, P6 comprises at least three contact points

P1, P2, P3, P4, P5, P6, e.g. three, four, five, six, or more contact points.

The boom 108 also comprises several installed sensors 430 for obtaining location information that is used for controlling the boom 108. An operator (not shown) of the boom 108 uses the sensors 430 to obtain at least the location information of a contact point P1, P2, P3, P4, P5, P6 when the operator drives the boom 108 so

N that its nozzle tip 115 contacts the surface 104 on that contact point P1, P2, P3, a 25 P4, P5, P6. 3

S The system 100 also comprises a controller (control part, control unit) 120 for con-

I trolling movements and operations of the boom 108. The controller 120 is operat- = ed by the operator. > io Fig. 2 and 3 present a definition process of the area(s) A1, A2, A3, A4 and spray-

S 30 ing movements 350 of the boom 108 on a grounds of the defined area(s) A1, A2,

N A3, A4 during a spraying process.

At step 252, the controller 120 presents and maintains a three-dimensional (3D) co-ordinate system 354, which has an origin O that locates in an attachment point, i.e. the attachment mechanism 110, of the boom 108.

The co-ordinate system 354 together with the location information from the sen- 5 sors 430 enables to locate the nozzle tip 115 in relation to the attachment mecha- nism 110, to define the area(s) A1, A2, A3, A4 to be sprayed, and to calculate the required movements 350 in order to perform the spraying of the defined area(s)

A1, A2, A3, A4 on the surface 104.

At step 256, when the machine 102 has been halted and the operator of the boom 108 has placed him-/herself so that it is possible to control the boom 108 safely, the operator, who operates the controller 120 by means of a user interface of re- mote controller 428, instructs the controller 120 to move the nozzle tip 115 close to a first point P1 on the surface 104. The first point P1 is meant to indicate a first boundary (edge), and in this example a vertical front (right) edge for the operator, of the area(s) A1, A2, A3, Ad on the surface 104.

At step 258, the operator instructs the controller 120 to move the boom 108 so that the nozzle tip 115, at the end of nozzle head 114, contacts the first point P1. All the time, during the movements of boom 108 and when the boom 108 is static, the sensors 430 provides the location information, which enables the controller 120 to define a location of nozzle tip 115.

At step 260, when the nozzle tip 115 is in contact with the surface 104 on the first point P1, the controller 120 provides a location L1 (x1, y1, z1) of first point P1 for the co-ordinate system 354 on a grounds of the location information from the sen- en sors 430 and the operator instructs the controller 120 to store this location L1 into

S 25 its memory part 434.

S At step 262, after storing the location L1, the operator instructs the controller 120 3 to move the nozzle tip 115 in a substantially horizontal direction and without con-

E tacting the surface 104 from the first point P1 close to a second point P2 on the © surface 104. The second point P2 is meant to indicate a second boundary, in this & 30 example a vertical rear (left) edge, of the area(s) A1, A2, A3, Ad. oO > At step 264, the operator instructs the controller 120 to move the boom 108 so that the nozzle tip 115 contacts a second point P2.

At step 266, when the nozzle tip 115 is in contact with the surface 104 on the sec- ond point P2, the controller 120 provides a location L2 (x2, y2, z2) of second point

P2 and the operator instructs the controller 120 to store it into the memory part 434. A horizontal line P1-P2 between the first and second points P1, P2 forms a third boundary, in this example a horizontal lower edge, for the area(s) A1, A2, A3,

A4 to be sprayed and, at the same time, a length 11 of the area(s) A1, A2, A3, A4.

At step 268, when the location L2 has been stored, the operator instructs the con- troller 120 to move the nozzle tip 115 in a substantially vertical direction and with- out contacting the surface 104 from the second point P2 close to a third point P3 on the surface 104. The third point P3 is meant to indicate a fourth boundary, a horizontal upper edge in this example, for the area A1 and, at the same time, a width w1 of the area A1.

At step 270, the operator instructs the controller 120 to move the boom 108 so that the nozzle tip 115 contacts the third point P3.

At step 272, when the nozzle tip 115 is in contact with the surface 104 on the third point P3, the controller 120 provides a location L3 (x3, y3, z3) of third point P3 and the operator instructs the controller 120 to store it into the memory part 434. A hor- izontal line, which is parallel with the third boundary (horizontal lower edge) and which trespasses the third point P3, intersects in points IS1, IS2 the first and sec- ond boundaries (front and rear edges) and forms the fourth boundary, in this ex- ample a horizontal upper edge, for the area A1.

Alternatively, the operator 120 may instruct the controller 120 to move the nozzle tip 115 in other direction from the second point P2 and to contact the surface 104 en on the third point P3' or P3” that also results corresponding stored location L3' or

S 25 [13 and the fourth boundary and the width w1 for the area A1 similarly as above © has been described in steps 268, 270, 272. > The purpose of the third point P3 (P3', P3”) is to define the width w1 to the area

E A1. The locations L1, L2, L3 (L3', L3”) of at least three points P1, P2, P3 (P3, © P3”) is sufficient for the controller 120 so that the area A1 is possible to define. 00

O 30 At step 274, when the location L3 has been stored and at least three points P1, > P2, P3 of area A1 have been defined, the controller 120 forms the four-cornered, sguare or rectangle-shaped area A1 by defining its four boundaries so that the first front boundary is a line starting upwards from the first point P1 and being perpen- dicular to the line P1-P2 between the first and second points P1, P2. The second rear boundary is a line starting upwards from the second point P2 and being per- pendicular to the line P1-P2. The third lower boundary is the line P1-P2, and the fourth upper boundary is the line that intersects in points IS1, IS2 the first and sec- ond boundaries as above has been described. The square-shaped or rectangle- shaped area A1 has a certain first surface area, which depends on distances be- tween the points P1, P2, P3. Its surface has a certain first angle in view of XY- plane, which substantially corresponds with a floor plane of tunnel profile 106, in the co-ordinate system 354. Finally, the operator instructs the controller 120 to store area information into the memory part 434.

Alternatively, it is possible to define the area(s) A1, A2, A3, A4 as parallelogram, whereupon the third point P3” defines a third corner of the parallelogram-shaped area(s) A1, A2, A3, A4. The first point P1 and the second point P2 define first and second corners of the parallelogram-shaped area(s) A1, A2, A3, A4, and, at the same time, the line P1-P2 as a third boundary. The second boundary is a line be- tween P2-P3”, whereupon the first boundary is a line that starts from the first point

P1 and is parallel to the line P2-P3” (second boundary). The fourth boundary is a line, which is parallel with the third boundary (line P1-P2) and which trespasses the third point P3”. The fourth boundary intersects in points IS1”, IS2” the first and second boundaries. The parallelogram-shaped area(s) A1, A2, A3, A4 also has — the certain first surface area and the certain first angle in view of XY-plane.

At step 276, after the formation of area A1 has been completed, if the operator wants to define at least one more sguare, rectangle, or parallelogram-shaped area

A2, A3, A4, the definition process continues at step 278 and the area A1 becomes a subarea A1. Alternatively, when the definition of area A1 is sufficient, the pro- - 25 cess continues at step 290.

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N At step 278, the operator instructs the controller 120 to move the nozzle tip 115

O again in a substantially vertical direction and without contacting the surface 104

S from the third point P3 (P3', P3”) close to a fourth point P4 on the surface 104.

I The fourth point P4 is meant to indicate a fifth boundary, in this example a horizon- = 30 tal upper edge, for a subarea A2 and a width w2 of the subarea A2.

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S The location of fourth point P4 may be other than described in the figures similarly

S as in the case of the third point P3.

At step 280, the operator instructs the controller 120 to move the boom 108 so that the nozzle tip 115 contacts the fourth point point P4.

At step 282, when the nozzle tip 115 is in contact with the surface 104 on the fourth point P4, the controller 120 provides a location L4 (x4, y4, z4) of fourth point

P4 and the operator instructs the controller 120 to store it into the memory part 434. A horizontal line, which is parallel with the fourth boundary and which tres- passes the fourth point P4, intersects in points IS3, 154 the first and second boundaries (front and rear edges) and forms the fifth boundary, in this example a horizontal upper edge, for the subarea A2 and the width w2.

At step 284, when the location L4 has been stored and the fourth point P4 of sub- area A2 has been defined, the controller 120 forms in this example the four- cornered, square or rectangle-shaped subarea A2 by defining its four boundaries.

The line starting upwards from the first point P1 (perpendicular to the line P1-P2) is the first front boundary and the line starting upwards from the second point P2 (perpendicular to the line P1-P2) is the second rear boundary, the line IS1-1S2 be- tween the intersection points IS1, IS2 is the third lower boundary and the line 1S3- 184 between the intersection points IS3, 154 is the fourth upper boundary. The subarea A2 also has a certain second surface area, which depends on distances between the points IS1, IS2, P4 and which may differ from the first surface area.

Its surface has a certain second angle in view of XY-plane, which may differ from the first angle. Finally, the operator instructs the controller 120 to store area infor- mation into the memory part 434.

At step 286, after the formation of subarea A2 has been completed, if the operator wants to define more subareas A3, Ad, the definition process for following subare- as A3, A4 continues at step 278 correspondingly as above described by contacting points P5, P6, providing locations L5, L6, and forming the subareas A3, A4. Alter- — natively, if all necessary subareas A1, A2, A3, A4 have been defined, the definition & process continues to step 288.

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S from the defined subareas A1, A2, A3, A4 by combining those in the co-ordinate

I system 354.

S 30 At step 290, the operator instructs the controller 120 about a spraying distance d, io which defines a distance between a surface of the formed area A1, A2, A3, A4 and

S the nozzle tip 115. The spraying distance d effects to the spraying movements 350, which the controller 120 calculates, because a spray discharging from the nozzle tip 115 has a cone shape, whereupon the larger the spraying distance d is, the larger a hitting area of the spray is.

On the grounds of the spraying distance d, the controller 120 defines starting and stopping locations of the spraying process for the nozzle tip 115 in the co-ordinate system 354 on the grounds the formed area A1, A2, A3, A4. and a position for the nozzle tip 115 for each area A1, A2, A3, A4 in relation to the formed area A1, A2,

A3, A4 (on the grounds of the surface angle(s)). The position for each area A1, A2,

A3, A4 is such that the nozzle tip 115 is substantially, perpendicular to the surface 104 of the area A1, A2, A3, Ad

The operator also instructs the controller 120 about a desired layer thickness, which is obtained by adjusting a speed of the nozzle tip 115 and, possibly, by ad- justing a power of a concrete pump in the machine 102. The layer thickness may be e.g. 10-150 mm, e.g. 30, 40, 50, 60, 70, 80, or 90 mm.

At step 292, the operator instructs the controller 120 to start the spraying of con- crete or other material, whereupon it starts to drive the boom 108 (nozzle tip 115) towards the calculated starting point and, after entering the starting point, to start — to spray.

At step 294, the controller 120 calculates the spraying movements 350, which are performed by the structures 112, 113, 114 of the boom 108, during spraying step by step, by taking the form of the surface of the area A1, A2, A3, A4 and the in- structed (received) spraying distance d into account. The controller 120 calculates the movements 350 so that the hitting area of concrete spray maintains inside the boundaries of the formed area(s) A1, A2, A3, Ad.

The step-by-step calculation enables the controller 120 to re-calculate the spraying movements 350, if the operator instructs the controller 120 during a spraying en movement 350 to lengthen or shorten this movement 350 in a direction of a length

S 25 of the area A1, A2, A3, Ad. © ? At step 296, the controller 120 controls the machine 102 and the boom 108 to 3 spray the defined area A1, A2, A3, A4 in accordance with the calculated move-

N

3 30 The operator may instruct the controller 120 to adjust a layer thickness of a

S sprayed material before or during the spraying by adjusting a speed of the spray- ing movements 350 in accordance with the desired layer thickness.

Fig. 4 presents the controller (control part, control unit) 120 that is used to control the spraying boom 104.

The controller 120 comprises a processor part 422 that performs operator and/or computer program initiated instructions, and processes data in order to run appli- cations. The processor part 422 may comprise at least one processor, e.g. one, two, three, or more processors.

The controller 120 also comprises a data transfer part 424 that the controller 120 uses in order to send commands, requests, and data to other components of the system 100, e.g. the movement mechanism 426 and a wireless remote controller 428, which provides a user interface for the operator to use the controller 120 and to control the boom 108. The data transfer part 424 also receives commands, re- quests, and data from the other components, e.g. the movement mechanism 426, remote controller 428, and the sensors 430. The communication between the data transfer part 424, and the components 426, 430 may be provided through a wired cable connections or wirelessly, and between the data transfer part 424 and the remote controller 428 wirelessly.

The controller 120 also comprises a power supply part 432. The power supply part 432 comprises components for powering the controller 120, e.g. components to connect the controller 120 to a power supply system of machine 102 or its own battery.

The controller 120 also comprises a memory part 434 in order to store and to maintain data. The data may be instructions, computer programs, and data files.

The memory part 434 comprises at least one memory, e.g. one, two, three, or

S more memories. o 25 The memory part 434 stores at least a data transfer application 436 for operating ? (controlling) the data transfer part 424, a movement application 438 for operating 3 the movement mechanism 426 of the boom 108, a sensor application 440 for op-

O 30 The memory part 434 also stores a computer program 444 (software, application), > which uses at least one of parts 424, 426, 430, 432 in order to perform at least the operations of controller 120 described above in this description and figures, when it is run in a computer, e.g. in the controller 120, by means of the processor part 424.

The computer program 444 may be stored in e.g. a Compact Disc (CD) or Univer- sal Serial Bus (USB) -type storage device.

The invention has been described above with reference to the above-mentioned exemplary embodiments and its several advantages have been demonstrated. It is clear that the invention is not only restricted to these embodiments, but comprises all possible embodiments within the following claims. e]

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Claims

1. A definition system (100) for defining a spraying area (A1, A2, A3, A4) for a spraying machine (102), comprising a spraying boom (108) of the machine, sensors (430) of the boom, and a controller (120) for controlling the boom, wherein the sensors are configured to obtain (258, 264, 270, 280) location in- formation, characterized in that a nozzle tip (115) of the boom is configured to contact several contact points (P1, P2, P3, P4, P5, P6) to define boundaries of the area to be sprayed on a surface (104) and the sensors are configured to obtain location information of the nozzle tip (115) in each contact point (P1, P2, P3, P4, P5, P6) so that the controller is configured to define (260, 266, 272, 282) location (L1, L2, L3, L4, L5, L6) of the each contact point in a co-ordinate system (354) of the boom on a grounds of the obtained location information so that defined locations (L1, L2, L3, L4, L5, L6) of the contact points are used to form (274, 288) the area to be sprayed in the co-ordinate system.

2. The system according to the preceding claim, wherein the controller presents (252) the co-ordinate system, which is a three-dimensional co-ordinate system (250) having an origin (O) that locates at an attachment mechanism (110) of the boom, whereupon the each contact point in the co-ordinate system is located in re- lation to the attachment mechanism.

3. The system according to any of the preceding claims, wherein the controller receives (290) a spraying distance (d), which determines a first distance between 2 25 the surface to be sprayed and the nozzle tip, from an operator of the boom, N whereupon the controller takes the form of the surface of each formed area (A1, O A2, A3, A4) and the spraying distance into account when spraying movements S (350) are calculated. E:

4. The system according to any of the preceding claims, wherein the controller S 30 defines (290) at least starting and stopping locations for a concrete spraying in the io co-ordinate system and a position for the nozzle tip (115) in relation to the each S formed area.

5. The system according to any of the preceding claims, wherein the controller calculates (294) spraying movements (350), which are performed by a structure

(112, 113, 114) of the boom during concrete spraying, for the nozzle tip on the grounds of a form of a surface of the formed area in the co-ordinate system.

6. The system according to claim 4, wherein the controller re-calculates (294) the spraying movements, if an operator of the boom controls the boom during a spraying movement (250) so that it lengthens or shortens this spraying movement in a direction of a length (11, 12) of the area.

7. The system according to claim 4, wherein the controller adjusts (296) a speed of the spraying movements in accordance with a desired layer thickness of a sprayed material.

8 The system according to any of the preceding claims, wherein the length (11) of the area is defined by contacting first and second contact points (P1, P2), whereupon a second distance between these points is the length, and a width (w1) of the area is defined by contacting a third contact point (P3), whereupon a third distance between the third contact point and a line between the first and second contact points (P2, P3) is the width (w1) of the area.

9. The system according to claim 6, wherein the area is a first subarea (A1) and a width (w2) of a second subarea (A2) is defined by contacting a fourth contact point (P4), whereupon a fourth distance between the fourth contact point and the first subarea is the width of the second subarea and a length (12) of the second subarea corresponds with the length of the first subarea.

10. The system according to claim 9, wherein the controller forms (288) the area by combining at least the first and second subareas (A1, A2). Q 11. A definition method for defining a spraying area (A1, A2, A3, A4) for a spray- N ing machine (102) by means of the definition system (100) according to any of the O 25 preceding claims, comprising at least steps of S contacting (258, 264, 270, 280), by a nozzle tip (115) of a spraying boom I (108) several contact points (P1, P2, P3, P4, P5, P6) in order to define boundaries = of the area to be sprayed on the surface (104), & obtaining (258, 264, 270, 280), by sensors (430) of the boom, location infor- o 30 mation of the nozzle tip in each contact point (P1, P2, P3, P4, P5, P6), and > defining (260, 266, 272, 282), by a controller (120) of the boom, location (L1, L2, L3, L4, L5, L6) of the each contact point in a co-ordinate system (354) of the boom on a grounds of the obtained location information so that defined locations

(L1, L2, L3, L4, L5, L6) of the contact points are used to form (274, 288) the area to be sprayed in the co-ordinate system.

12. A controller (120) for defining a spraying area (A1, A2, A3, A4) comprising a processor part (422), a data transfer part (424), and a memory part (434), wherein the data transfer part is configured to receive (258, 264, 270, 280) location information, characterized in that the location information is location information of each contact point (P1, P2, P3, P4, P5, P6) from sensors (430) of the spraying boom (108) to which contact points (P1, P2, P3, P4, P5, P6) a nozzle tip (115) of the boom has contacted (258, 264, 270, 280) when boundaries of the area to be sprayed has been defined on a surface (104), whereupon the processor part to- gether with the memory part is configured to define (260, 266, 272, 282) location (L1, L2, L3, L4, L5, L6) of the each contact point in a co-ordinate system (354) of the boom on a grounds of the received location information so that defined loca- tions (L1, L2, L3, L4, L5, L6) of the contact points are used to form (274, 288) the area to be sprayed in the co-ordinate system.

13. Adefinition method for defining a spraying area (A1, A2, A3, A4) by means of the controller (120) according to claim 12, comprising at least steps of receiving (258, 264, 270, 280), by the data transfer part (424), location infor- mation of each contact point (P1, P2, P3, P4, P5, P6) from the sensors (430) of the spraying boom (108) to which contact points (P1, P2, P3, P4, P5, P6) the noz- zle tip (115) of the boom has contacted (258, 264, 270, 280) when the boundaries of the area to be sprayed has been defined on the surface (104), and N defining (260, 266, 272, 282), by the processor part (422) together with the o memory part (434), the location (L1, L2, L3, L4, L5, L6) of the each contact point in ? the co-ordinate system (354) of the boom on a grounds of the received location in- 3 formation so that the defined locations (L1, L2, L3, L4, L5, L6) of the contact points E 30 are used to form (274, 288) the area to be sprayed in the co-ordinate system. &

14. A computer program (444) comprising instructions, which, when the comput- 3 er program is executed by a controller (120) according to claim 12, cause the con- > troller to carry out at least the steps of the method according to claim 13.

15. A tangible, computer readable medium comprising the computer program — (444) according to claim 14.