Abrasive floor processing robot and method for transporting the same

Abstract

The invention relates to a abrasive floor processing robot for grinding and / or brushing a surface (4). The abrasive floor processing robot comprises support elements (2), in particular wheels, for supporting the abrasive floor processing robot on the surface (4). Furthermore, at least one abrasive processing element (3) with a grinding and / or brushing layer (6) is arranged at the abrasive floor processing robot for grinding and / or brushing the surface (4). A control unit (17) controls the abrasive floor processing robot. The abrasive floor processing robot comprises a variable pressure system for pressing the abrasive processing element (3) with different pressures against the floor.

Description

[0001] ABRASIVE FLOOR PROCESSING ROBOT AND METHOD FOR TRANSPORTING THE SAME

[0002] Technical Field

[0003] The present invention relates to an abrasive floor processing robot for grinding and / or brushing a surface , in particular a ground . The abrasive floor processing robot comprises support elements for supporting the abrasive floor processing robot on the surface , at least one abrasive processing element with a grinding and / or brushing layer for grinding and / or brushing the surface , and a control unit for controlling the abrasive floor processing robot . Background Art

[0004] Floor grinding, brushing and polishing machines are well known to the skilled person . Such abrasive floor processing machines can be used to level uneven spots , renovate old floors , polishing and grinding surfaces or to remove adhesive residues , paintings , coatings etc . Floors made of wood, stone , concrete etc . can be prepared by such machines .

[0005] Known floor grinding machines comprise grinding discs , a device for capturing the dust and are permanently controlled by a user . A grinding machine might have a grinding disc with a diameter of 40 cm and a total weight of more than 100 kg . Heavy weight elements are part of the grinding machine to press the grinding disc against the floor .

[0006] Transport trolleys exist for moving a floor grinding machine to the working area . Moving the floor grinding machine to upper floors of a house is a tedious matter .

[0007] Disclosure of the Invention

[0008] The problem to be solved by the present invention is to provide an abrasive floor processing robot , which is flexible in use .

[0009] This problem is solved by the abrasive floor processing robot according to the independent device claim . According to this , the abrasive floor processing robot for grinding and / or brushing a surface , in particular for grinding and / or brushing a flat surface , in particular for grinding and / or brushing a ground, comprises

[0010] - support elements for supporting the abrasive floor processing robot on the surface . The support elements might be wheels or caterpillars . In particular, the support elements are powered for moving the abrasive floor processing robot . - at least one abrasive processing element with a grinding and / or brushing layer for grinding and / or brushing the surface . The abrasive processing element is not a cleaning device , but suitable for removing part of the surface . In particular, the abrasive floor processing element might be a disc, a belt or a roll . The grinding and / or brushing layer might be made of glass , aluminium oxide , ceramic, diamond, sand, brushing elements etc . A disc might have a diameter of 40 cm . Alternatively, the abrasive floor processing robot might comprise more than one abrasive processing element , in particular three abrasive processing elements , in particular three grinding discs .

[0011] - a control unit for controlling the abrasive floor processing robot .

[0012] - a variable pressure system for pressing the abrasive processing element with di f ferent pressures against the floor .

[0013] In particular, the control unit determines the pressure dependent on a user input , and / or on sensor data, i . e . autonomously .

[0014] Such a variable pressure system allows grinding and / or brushing the surface with di f ferent pressures . For example , the abrasive floor processing robot can grind and / or brush a surface once with a high grinding and / or high brushing pressure or twice with hal f of the pressure , depending on the available time and depending on the required processing quality . The higher the grinding pressure , the faster the surface abrasion . The abrasive floor processing robot can be flexibly used for di fferent grinding and / or brushing tasks .

[0015] In particular, the variable pressure system is configured to press the abrasive processing element at least with a first pressure and a second pressure against the surface , wherein the second pressure is di f ferent to the first pressure . Advantageously, the abrasive floor processing robot comprises a li fting device for positioning the abrasive processing element in di f ferent vertical positions . The vertical positions of the abrasive processing element are distinguished in a working and non-working positions . In the working position, the grinding and / or brushing layer touches the surface and the surface is processed i f the abrasive processing element moves , in particular rotates or linearly moves . The pressure for pressing the abrasive processing element against the floor is generated by the variable pressure system . In a non-working position, the grinding and / or brushing layer is spaced from the surface . The abrasive floor processing robot can move without processing the surface .

[0016] Advantageously, the li fting device is configured such that the grinding and / or brushing layer is aligned with respect to the surface in such a way that plane / parallel processing of the surface is ensured . This allows a controlled grinding and / or brushing operation . In particular, the li fting device comprises two arms rotating in a parallel manner and connecting the abrasive processing element with the abrasive floor processing robot . A rotation of the two arms moves the abrasive processing element between at least two li fting positions . The two arms and the abrasive processing element move as a parallelogram .

[0017] Advantageously, the li fting device might comprises a linear actuator for moving the abrasive processing element from and to the surface .

[0018] In another preferred embodiment , the abrasive floor processing robot comprises a chassis . The support elements support the chassis . The abrasive processing element is arranged on the chassis and pressing against the surface . Actuators , in particular linear or eccentric actuators , are arranged at the support elements . They can move the chassis up and down, i . e . the support elements are the li fting device . I f the abrasive processing element touches the surfaces , the actuators arranged at the support elements can pull the chassis down and press the abrasive processing element against the surface . I . e . the linear actuators ful fil the function of the variable pressure system . In particular, the linear actuators are hydraulic, pneumatic or mechanic actuators . Alternatively, the support elements are wheels , wherein an air pump pumps air into the wheels and air can be evacuated from the wheels such that the wheels ful fil the function of the linear actuators

[0019] In a preferred embodiment , the abrasive floor processing robot is powered by at least one mobile power source element . This power source element might be at least one battery, at least one solar cell or at least one fuel cell . The abrasive floor processing robot can move autonomously since no cable connection to a power socket is required .

[0020] In particular, the at least one mobile power source is arranged such that its weight presses the abrasive processing element against the surface . No additional weights or only additional small weights are needed to weigh down the abrasive processing element on the surface . Alternatively, the mobile power sources make the abrasive floor processing robot heavy such that the variable pressure system can press the abrasive processing element with a correspondingly high pressure against the surface .

[0021] Advantageously, the abrasive floor processing robot comprises at least two slots for connecting simultaneously at least two of the mobile power sources with the abrasive floor processing robot , wherein the abrasive floor processing robot can be operated even i f at least one of the slots is empty and at least one of the slots is connected with the mobile power source . Depending on the required grinding pressure , the number of mobile power sources , which weigh down the abrasive processing element , can arbitrarily be chosen . I f only a small grinding pressure is needed, only one mobile power source can be connected with the abrasive floor processing robot via a slot . I f a higher weight is needed, several mobile power sources can be connected with the abrasive floor processing robot and weigh down the abrasive processing element .

[0022] In a preferred embodiment , the abrasive floor processing robot comprises at least one sensor unit for measuring a condition of the surface , wherein the control unit is adapted to determine after the surface is processed and depending on the measured data i f another process cycle is required . In particular, the at least one sensor unit comprises di f ferent sensor types , in particular a light sensor, a camera, a distance sensor and / or a tilt-sensor . Sensoring the processed surface allows the abrasive floor processing robot to process a surface autonomously and to handle di f ferent defects in the surface .

[0023] In particular, the abrasive floor processing robot is an at least partially, in particular fully, autonomously working abrasive floor processing robot . The behavior of the abrasive floor processing robot is defined by at least the following control parameters :

[0024] - locomotion speed . It defines the speed the abrasive floor processing robot is moving over a surface .

[0025] - speed of the grinding and / or brushing layer . I f the abrasive processing element is a disc, the movement speed is a rotation speed .

[0026] - pressure generated by the variable pressure system for pressing the abrasive processing element against the surface .

[0027] - in particular the type of the grinding and / or brushing layer, in particular the grit si ze of the abrasive compounds of the grinding layer and / or the density and / or strength of the brushing layer . The abrasive floor processing robot might have a collection of di f ferent abrasive processing elements which can autonomously or semi-autonomously be exchanged by the abrasive floor processing robot . Alternatively, the abrasive floor processing robot defines which type of grinding and / or brushing layer is required and the user mounts the corresponding abrasive processing element at the abrasive floor processing robot .

[0028] Controlling the abrasive floor processing robot with the mentioned parameters allows grinding and / or brushing di f ferent surfaces with di f ferent defects autonomously .

[0029] In particular, the control unit is adapted to define a movement traj ectory wherein the control parameters are determined at every location point on the movement traj ectory . The abrasive floor processing robot moves along the traj ectory and operates at every location point on the traj ectory with the defined parameters .

[0030] Advantageously, the movement traj ectory is adapted such that the abrasive floor processing robot moves a first time over a speci fic location point and a second time over said speci fic location point , wherein the control parameters are at least partially di f ferent when moving the first time over said speci fic location point compared to the second time . Such a behavior is advantageously, i f in a first step, the surface is grinded with a rough grinding layer, and in a second step, with a fine grinding layer or i f the surface is processed with di f ferent grinding mechanisms .

[0031] In a preferred embodiment , the abrasive floor processing robot comprises a vacuum cleaning system for collecting grinding and / or brushing dust and / or comprises surface finishing tools , in particular a polishing device , an oiling device , or a sealing device .

[0032] Advantageously, the abrasive floor processing robot comprises an arm with a separate abrasive processing element for grinding and / or brushing the surface close to a wall . In particular, the remaining part of the abrasive floor processing robot , in particular the abrasive processing element , is spaced from the wall while the ground close to the wall is grinded and / or brushed by the separate abrasive processing element . Such an arm allows grinding and / or brushing close to vertically extending walls without touching the wall with the support elements .

[0033] Furthermore , part of the invention is a method for transporting the mentioned abrasive floor processing robot between di f ferent floors of a house . Since the abrasive floor processing robot comprises heavy mobile power sources for weighing down the abrasive processing element , the mobile power sources can be connected and disconnected from the abrasive floor processing robot . Transporting the abrasive floor processing robot between di f ferent floors comprises the following steps :

[0034] - disconnecting at least one of the power sources from the abrasive floor processing robot ,

[0035] - transporting the abrasive floor processing robot separately from the at least one disconnected power source from a first location to a second location, in particular from a first floor to a second floor of a house ,

[0036] - reconnecting the at least one power source to the abrasive floor processing robot .

[0037] This modular design of the abrasive floor processing robot allows transporting it easily without any special carrying aids .

[0038] Other advantageous embodiments are listed in the dependent claims as well as in the description below .

[0039] Brief Description of the Drawings The invention will be better understood and obj ects other than those set forth above will become apparent from the following detailed description thereof . Such description makes reference to the annexed drawings , wherein :

[0040] Fig . 1 shows the abrasive floor processing robot according to the invention;

[0041] Fig . 2 shows the abrasive floor processing robot according to Fig . 1 wherein the vacuum cleaning system and the mobile power sources are hidden;

[0042] Fig . 3a shows a side view of the abrasive floor processing robot wherein the abrasive processing element is in a working position;

[0043] Fig . 3b shows the abrasive floor processing robot in a non-working position;

[0044] Fig . 4 shows an abrasive floor processing robot with a laterally extending arm with a separate abrasive processing element for grinding the surface close to a vertically extending wall ; and

[0045] Fig . 5 shows a traj ectory of the abrasive floor processing robot moving inside a room with a floor to be processed .

[0046] Modes for Carrying Out the Invention

[0047] Fig . 1 and Fig . 2 show an abrasive floor processing robot with a chassis 1 . The chassis 1 is supported by actuated di f ferential wheels 2 , which serve as support elements . An abrasive processing element is arranged between the wheels 2 and configured as a grinding disc 3 .

[0048] Alternatively, the abrasive processing element could be a brushing disc . A brushing disc works similarly to a grinding disc, which is why in the following, for the sake of simplicity, only a robot with a grinding disc will be described . The grinding disc 3 touches the surface 4, which is processed by the abrasive floor processing robot. The surface 4 is made of wood, concrete or another material, which can be grinded and / or brushed.

[0049] The grinding disc 3 has a circular shape and might have a diameter between 30 and 50 mm. Alternatively, the robot comprises more than one grinding disc, e.g. three grinding discs with smaller diameters.

[0050] A grinding layer 6 is arranged at the bottom of the grinding disc 3. The grinding layer 6 is directed against the surface 4. The grinding layer 6 comprises abrasive compounds for grinding the surface 4. The abrasive compounds might be made of garnet, aluminium oxide or silicon carbide. Alternative materials are possible. The abrasive compounds might consist of particles of standard sizes, i.e. with average particle diameters between 8 and 1'800 pm.

[0051] The grinding disc 3 is powered by an actuator 7 rotating the grinding disc 3 with different speeds, e.g. with speeds between 0 and 800 rpm.

[0052] Additionally, the robot comprises surface finishing tools, e.g. a polishing device, an oiling device and / or a sealing device.

[0053] A battery system is arranged on the chassis 1. The battery system comprises four slots for connecting batteries 8 with the abrasive floor processing robot. In Fig. 1, all slots are connected with a battery 8. One single battery might have a weight of 15 kg. The weight of the batteries 8 is necessary for making the robot heavy. The heavier the robot is, the more the grinding disc 3 can be pressed against the surface 4.

[0054] It is not necessary that all slots are connected with batteries 8. If a lower pressure on the grinding element 3 is desired, only one, two or three batteries could be connected with the abrasive floor processing robot via the slots of the battery system. The abrasive floor processing robot can be operated even if only one single slot is occupied.

[0055] Alternatively, the abrasive floor processing robot could be powered by solar cells or fuel cells.

[0056] The abrasive floor processing robot comprises a lifting device and a variable pressure system. The lifting device is adapted to move the grinding disc 3 up and down, i.e. in directions as shown in Fig. 3a by double arrow 10. The lifting device can position the grinding disc 3 in different vertical positions.

[0057] The variable pressure system can press the grinding disc 3 with different pressures against the surface 4.

[0058] Both, the lifting device and the variable pressure system are realized by an actuator 11, a vertical extension 12 extending from the actuator 11 and a support connection 13 connecting the extension 12 and the grinding disc 3. If the actuator 11 pulls the extension 12 downwards, the grinding disc 3 is pressed against the surface 4 via the support connections 13. The heavier the robot, the greater is the force with which the grinding disc 3 can be pressed to the surface 4.

[0059] If the actuator 11 moves the extension 12 upwards, the extension 12 pulls the grinding disc 3 upwards. The grinding disc 3 loses contact with the surface 4 and the robot can move without processing the surface 4.

[0060] The grinding disc 3 is connected with the chassis 1 via two rotating arms 14. The two rotating arms 14 are fixated at the chassis 1 and can be rotated around the fixation points 15. If the actuator 11 moves the grinding disc 3 upwards via the support element 13, the two rotating arms 14 rotate clockwise as shown by arrow 16. The two rotating arms 14 ensure that the grinding layer 6 is always parallel to the surface 4, i.e. horizontal. The two rotating arms 14, the chassis 1 and the grinding layer 6 form a parallelogram in every vertical position of the grinding disc 3 . I f the actuator 11 moves downwards , the two rotating arms 14 rotate counter clockwise .

[0061] Fig . 3a shows the grinding element 3 in its lowest li fting position . The variable pressure system presses the grinding layer 6 against the surface 4 . The pressure can be varied by moving the actuator 11 . Fig . 3b shows the robot in a non-working position . The grinding layer 6 does not touch the surface 4 . In such a non-working position, the abrasive floor processing robot can move without grinding the surface 4 .

[0062] Alternatively, the grinding disc 3 could be fixated at the chassis 1 and not be moved relative to the chassis 1 . In this case , linear actuators could be arranged at the wheels for moving the chassis 1 with the grinding disc 3 up and down . The actuators could be hydraulic, pneumatic or mechanic actuators . Alternatively, an air pump could be provided pumping air into the wheels

[0063] 2 moving the chassis 1 and the grinding element 3 upwards . The chassis 1 and the grinding disc 3 could be lowered by evacuating air from the wheels 2 .

[0064] Furthermore , Fig . 1 shows a vacuum cleaning system 18 . The vacuum cleaning system 18 collects dust generated by the grinding operation of the grinding disc

[0065] 3 .

[0066] As shown in Fig . 3a, sensors units 19 and 20 are arranged on the chassis 1 . The sensor unit 19 is arranged on the rear side and measures the condition of the surface 4 after the surface 4 has been processed . The sensor unit comprises a camera and a distance sensor .

[0067] A control unit 17 is arranged above the batteries 8 for controlling the abrasive floor processing robot . The control of the abrasive floor processing robot is illustrated by Fig . 5 , which shows a sketch of a room with a square floor . A traj ectory is shown, which the abrasive floor processing robot moves along . The abrasive floor processing robot starts its operation at point A. It moves with a predefined locomotion speed of ( e . g . constant 0 . 5 m per s ) from point A to point B . The grinding layer 6 of the grinding disc 3 rotates with a constant speed of 600 rpm . The grinding disc 3 is positioned in a working position such that the grinding layer 6 touches the floor of the room when grinding . As soon as the abrasive floor processing robot arrives at point B, the abrasive floor processing robot stops the rotation of the grinding layer 6 or the actuator 11 moves the extension 12 upwards until the grinding layer 6 reduces or loses contact with the floor . The abrasive floor processing robot rotates by 90 ° , starts again rotating the grinding layer 6 and continues moving to point C .

[0068] As soon as the abrasive floor processing robot has grinded the complete floor and arrives at point D, the abrasive floor processing robot stops moving and stops the rotation of the grinding layer 6 . The actuator 11 moves the extension 12 upwards until the grinding layer 6 loses contact with the floor . The abrasive floor processing robot moves back to the starting point A following the dashed line . During this movement , the grinding disc 3 does not rotate and does not touch the floor . The grinding disc 3 is in a non-working position .

[0069] At every location point on the traj ectory, the control unit 17 defines the locomotion speed of the abrasive floor processing robot , the rotational speed of the grinding disc 3 , and the vertical positioning of the grinding disc 3 . In the example shown by Fig . 5 , the abrasive floor processing robot is always working with the same type of grinding layer 6 . However, it is possible that the abrasive floor processing robot works with a first type of a grinding layer on a first part of the traj ectory and works with a second type of a grinding layer on a second part of the traj ectory . When changing the grinding layer, the abrasive floor processing robot might send an alert to the user and the user has to exchange the grinding layer as instructed by the control unit 17 .

[0070] Fig . 4 shows the abrasive floor processing robot with a separate abrasive processing element 21 arranged at an arm 22 laterally extending from the floor processing robot . The separate abrasive processing 21 is suitable for grinding and / or brushing the surface 4 close to a wall 23 . The remaining part of the abrasive floor processing robot , in particular the abrasive processing element 3 is spaced from the wall .

Claims

Claims1. An abrasive floor processing robot for grinding and / or brushing a surface (4) , in particular a ground,- support elements (2) for supporting the abrasive floor processing robot on the surface (4) ,- at least one abrasive processing element (3) with a grinding and / or brushing layer (6) for grinding and / or brushing the surface (4) ,- a control unit (17) for controlling the abrasive floor processing robot, characterized in that the abrasive floor processing robot comprises a variable pressure system for pressing the abrasive processing element (3) with different pressures against the floor.

2. The abrasive floor processing robot according to claim 1, wherein the variable pressure system is configured to press the abrasive processing element (3) at least with a first pressure and a second pressure, which is different to the first pressure, against the surface .

3. The abrasive floor processing robot according to any one of the preceding claims, wherein the abrasive floor processing robot comprises a lifting device for positioning the abrasive processing element (3) in different vertical positions, in particular configured to position the abrasive processing element (3) in a nonworking position for moving the abrasive floor processing robot without touching the surface (4) with the abrasive processing element (3) .

4. The abrasive floor processing robot according to any one of the preceding claims, wherein the lifting device is configured such that the grindingand / or brushing layer is aligned with respect to the surface in such a way that plane processing of the surface is ensured.

5. The abrasive floor processing robot according to claim 3 or 4, wherein the lifting device comprises two arms (14) rotating in a parallel manner and connecting the abrasive processing element (3) with the abrasive floor processing robot.

6. The abrasive floor processing robot according to one of the preceding claims, comprising an actuator (11) , in particular a linear actuator, configured to press the abrasive processing element (3) with different pressures against the surface, i.e. fulfilling the function of the variable pressure system.

7. The abrasive floor processing robot according to claim 3 and according to one of the preceding claims, wherein the actuator is configured to position the abrasive processing element (3) in different vertical positions, i.e. fulfilling the function of the lifting device .

8. The abrasive floor processing robot according to any one of the preceding claims, comprising a chassis (1) supporting the abrasive processing element (3) and supported by the support elements (2) , wherein the support elements (3) comprise, in particular linear or eccentric, actuators moving the chassis (1) up and down and pulling the chassis (1) down to press the abrasive processing element (3) against the surface with different pressures, in particular wherein- the actuators are hydraulic, pneumatic or mechanic actuators, or- the support elements (2) are wheels, wherein an air pump pumps air into the wheels and air canbe evacuated from the wheels such that the wheels fulfil the function of the actuators.

9. The abrasive floor processing robot according to any one of the preceding claims, wherein the abrasive floor processing robot is powered by at least one mobile power source element (8) , in particular at least one battery, at least one solar cell and / or at least one fuel cell.

10. The abrasive floor processing robot according to claim 9, wherein the at least one mobile power source (8) is arranged such that its weight can be used for pressing the abrasive processing element against the surface, in particular wherein the at least one mobile power source (8) presses with its weight the abrasive processing unit directly against the surface or wherein the at least one mobile power source makes the abrasive floor processing robot heavy such that the variable pressure system can press the abrasive processing element (3) with a corresponding pressure against the surface.

11. The abrasive floor processing robot according to claim 9 or 10, comprising at least two slots for connecting simultaneously at least two of the mobile power sources (8) with the abrasive floor processing robot, wherein the abrasive floor processing robot can be operated even if at least one of the slots is empty and at least one of the slots is connected with the mobile power source (8) .

12. The abrasive floor processing robot according to any one of the preceding claims, comprising at least one sensor unit (19, 20) for measuring a condition of the surface (4) , wherein the control unit (17) isadapted to determine after the surface (4) is grinded and / or brushed and depending on the measured data if another grinding and / or brushing cycle is required.

13. The abrasive floor processing robot according to claim 12 wherein the at least one sensor unit (19, 20) comprises different sensor types, in particular a light sensor, a distance sensor and / or a camera.

14. The abrasive floor processing robot according to any one of the preceding claims, wherein the abrasive floor processing robot is an at least partially autonomously working robot and wherein the behavior of the robot is defined by at least the following control parameters :- locomotion speed,- grinding and / or brushing speed, in particular rotation speed, of the grinding and / or brushing layer (6) ,- pressure generated by the variable pressure system,- in particular, type of the grinding and / or brushing layer (6) , in particular the grit size of the grinding layer (6) or the density and / or strength of the brushing layer (6) .

15. The abrasive floor processing robot according to claim 14, wherein the control unit (17) is adapted to define a movement trajectory wherein the control parameters are determined at every location point on the movement trajectory.

16. The abrasive floor processing robot according to claim 15, wherein the movement trajectory is adapted such that the abrasive floor processing robot moves a first time over a specific location point and a second time over said specific location point, whereinthe control parameters are at least partially, in particular the movement speed, different when moving the first time over said specific location point compared to the second time.

17. The abrasive floor processing robot according to one of the claims 14 to 16, wherein the control parameters are determined dependent on- texture of the surface, in particular a wood texture,- degree of wear,- laying direction, in particular of a parquet floor,- room geometry,- obstacles.

18. The abrasive floor processing robot according to any one of the preceding claims, wherein the control unit (17) determines the pressure of the variable pressure system dependent on- a user input, and / or- sensor data.

19. The abrasive floor processing robot according to any one of the preceding claims, wherein the at least one abrasive processing element (3) is at least one grinding and / or brushing disc or a grinding and / or brushing belt.

20. The abrasive floor processing robot according to any one of the preceding claims, wherein the abrasive floor processing robot comprises- a vacuum cleaning system (18) for collecting grinding dust, and / or- surface finishing tools, in particular a polishing device, an oiling device, or a sealing device.

21. The abrasive floor processing robot according to any one of the preceding claims, comprising an arm (22) with a separate abrasive processing element (21) for grinding and / or brushing the surface close to a wall, in particular wherein the remaining part of the abrasive floor processing robot, in particular the abrasive processing element (3) , is spaced from the wall while the surface close to the wall is processed by the separate abrasive processing element.

22. Method for transporting the abrasive floor processing robot according to claim 9 and according to any one of the preceding claims, comprising the following steps- disconnecting at least one of the mobile power sources (8) from the abrasive floor processing robot,- transporting the abrasive floor processing robot separately from the at least one disconnected mobile power source (8) from a first location to a second location, in particular from a first floor to a second floor of a house,- reconnecting the at least one of the mobile power source (8) to the abrasive floor processing robot.

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