A floor grinder with automated control of applied tool pressure

Abstract

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Description

TECHNICAL FIELD The present disclosure relates to surface processing equipment such as floor grinders for processing concrete surfaces, and in particular to surface processing equipment adapted 5 to automatically adjust an applied tool pressure against the surface which is being processed. BACKGROUND Any discussion of the prior art throughout the specification should in no way be considered 10 as an admission that such prior art is widely known or forms part of common general knowledge in the field. Concrete surfaces are commonly used for flooring in both domestic and industrial facilities. The size of concrete surface floors ranges from a few square meters for a domestic garage floor and the like to thousands of square meters in larger industrial facilities. Concrete 15 surfaces offer a cost efficient and durable flooring alternative and have therefore gained popularity over recent years. Surface processing equipment such as floor grinders and power trowels can be used to efficiently process a hard material surface such as a concrete surface in order to, e.g., obtain a level surface having a uniform topology and / or a surface having a desired surface 20 texture. Surface processing equipment can also be used to polish a surface in order to obtain a glossy surface finish, or to clean a surface. Successful concrete surface processing normally requires configuration of several machine operating parameters. This may pose a challenge to an inexperienced machine operator. It is desired to reduce the need for manual configuration of operating parameters in surface 25 processing equipment. It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative. 2026200332   11 Jun 2026 SUMMARY According to a first aspect, the invention provides processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, 5        the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and adapted to support the surface processing equipment on the surface, where the at least one actuator is adapted to control a position of the 10 adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to the support arrangement and in relation to a mass center of the active part, where the surface processing equipment is adapted to be automatically tipped over 15 about a contact area between the surface and the support arrangement, in response to control of the position of the mass center of the adjustable mass part by the at least one actuator towards a rear of the surface processing equipment. Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense 20 as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. According to a second aspect the invention provides a computer implemented method performed in a control unit adapted to control an operation of surface processing equipment for processing a surface, the equipment comprising an 25 active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and adapted to support the surface processing equipment on the surface, where the at 30 least one actuator is adapted to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to a mass center of the support arrangement and in relation 2026200332   11 Jun 2026 to a mass center of the active part, the method comprising automatically tipping the surface processing equipment over about a contact area between the surface and the support arrangement by means of controlling the position of the mass center of the adjustable mass part by the at 5 least one actuator towards a rear of the surface processing equipment. According to another aspect the invention provides surface processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support 10 respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and adapted to support the floor grinder on the surface, where the at least one actuator is adapted to control a position of the 15 adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to a mass center of the support arrangement and in relation to a mass center of the active part, where the surface processing equipment is adapted for rotation about a 20 contact area between the surface and the support arrangement to a tipped over position for providing access to the one or more tool carriers, and to be automatically biased toward the tipped over position in response to control of the position of the mass center of the adjustable mass part by the at least one actuator towards a rear of the surface processing equipment. 25 According to one preferred aspect of the present disclosure, there is provided surface processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support 30 arrangement is connected to the active part and adapted to support the floor grinder on the surface, where the surface processing machine is devoid of a handle portion for guidance 2026200332   11 Jun 2026 of the surface processing equipment on the surface, where the at least one actuator is adapted to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to the support arrangement 5 and in relation to a mass center of the active part, where the surface processing equipment is adapted to be tipped over (T) about a contact area between the surface and the support arrangement, at least in part due to control of the position of the mass center of the adjustable mass part by the at least one actuator towards a rear (R) of the surface processing equipment. 10 According to another preferred aspect of the present disclosure, there is provided a computer implemented method performed in a control unit adapted to control an operation of surface processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support 15 respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and adapted to support the floor grinder on the surface, where the at least one actuator is adapted to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center 20 of the adjustable mass part in relation to a mass center of the support arrangement and in relation to a mass center of the active part, the method comprising obtaining (S1) data indicative of a difference between a current tool pressure and a desired tool pressure, and controlling (S2) a state of the at least one actuator to reduce the difference between current tool pressure and desired tool pressure. 25 According to another preferred aspect of the disclosure, there is provided surface processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support 30 arrangement is connected to the active part and adapted to support the floor grinder on the surface, where the at least one actuator is adapted to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to a mass center of the support arrangement and in relation to a mass center of 2026200332   11 Jun 2026 the active part, where the surface processing equipment is arranged to be guided solely from a distance, wherein the surface processing machine is devoid of a handle portion for manual guidance of the surface processing equipment on the surface. According to another preferred aspect of the present disclosure, there is provided a surface 5 processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and adapted to support the floor grinder on the 10 surface, where the at least one actuator is adapted to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to a mass center of the support arrangement and in relation to a mass center of the active part, where the control unit is configured to control a state of the at least one 15 actuator, by the control signal, to reduce a difference between a current tool pressure and a desired tool pressure. According to another preferred aspect of the present disclosure, there is provided a surface processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, 20 the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and adapted to support the floor grinder on the surface, where the at least one actuator is adapted to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to 25 a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to a mass center of the support arrangement and in relation to a mass center of the active part, where the control unit is configured to control a state of the at least one actuator during rotating engagement between the one or more tool carriers and the surface. According to another preferred aspect of the present disclosure, there is provided a surface 30 processing equipment for processing a surface, the equipment comprising an active part, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and 2026200332   11 Jun 2026 adapted to support the floor grinder on the surface, the support arrangement comprising at least one support wheel actuator adapted to control a vertical and / or horizontal position of at least one support wheel of the support arrangement in response to a control signal, where the control unit is configured to control a state of the at least one support wheel actuator by 5 the control signal to reduce a difference between a current tool pressure and a desired tool pressure. According to another preferred aspect of the present disclosure, there is provided a surface processing equipment for processing a surface, the equipment comprising an active part, a support arrangement, and a control unit, the active part comprising one or more tool carriers 10 arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, the one or more tool carriers extend in a tool carrier plane, where at least one tool carrier adjustment actuator is adapted to control a pose of the active part relative to the surface in response to a pose control signal, where the control unit is configured to control the at least one tool carrier adjustment actuator by the pose control 15 signal to reduce a difference between a current pose and a desired pose. According to some of the examples described herein, the surface processing equipment comprises an active part, an adjustable mass part, at least one actuator, a support arrangement, and at least one control unit. The active part is the part that is used to process the surface, i.e., the part that comprises the tools. The adjustable mass part can take on 20 many different forms, but comprises some form of weight which is displaceable relative to the active part by the actuator. The support arrangement comprises wheels or the like which support the equipment on the surface at least party. The control unit may be arranged onboard the surface processing equipment and / or in a remote control device associated with the surface processing equipment. It is also possible that parts of the control 25 functionality of the surface processing equipment is located at a remote server. The active part of the surface processing equipment comprises one or more tool carriers that are arranged to hold respective tools configured to rotatably engage the surface at an applied tool pressure, such as abrasive tools used in floor grinding operations, polishing pads used to clean or polish a floor surface, or trowel blades used to even out a maturing concrete 30 surface. The applied tool pressure may be given in Newton per square meter (N / m2), pounds per square inch (psi), or the like. The support arrangement is connected to the active part and adapted to support the floor grinder on the surface, i.e., the equipment is supported in part by the tools and in part by the support arrangement which may comprise, e.g., one or more support wheels or a support roller. The at least one actuator is adapted 2026200332   11 Jun 2026 to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal from the control unit. This way the position of the mass center of the adjustable mass part can be shifted by the control unit in relation to the mass center of the support arrangement and in relation to the mass center 5 of the active part in order to automatically adjust the current applied tool pressure. The adjustable mass part can for instance be pivotably and / or slidably connected to the active part such that it can rotate about a pivot axis and / or slide along a track. The relative positions of the mass centers of the surface processing equipment parts in relation to the contact area between the support arrangement and the surface has a regulating effect on 10 the applied tool pressure, as will be discussed in more detail in the following. The control unit is configured to automatically control a state of the at least one actuator and thus also the position of the adjustable mass part on the surface processing equipment to reduce a difference between a current tool pressure and a desired tool pressure. This way the efficiency and / or end result of the surface processing operation performed by the surface 15 processing equipment is improved. The automatic operation by the control unit reduces the need for manual configuration of the surface processing equipment, which is an advantage. The at least one actuator can be a linear actuator, such as a hydraulic piston, which is arranged to control a tilt angle of the adjustable mass part in dependence of a control signal from the control unit, or a rotary actuator, such as a slew drive, worm gear, or the like, that 20 is arranged to control the tilt angle in dependence of a control signal from the control unit. The adjustable mass part may be a body part of the surface processing equipment and / or separate weights pivotably attached to the active part. The body part forming (part of) the adjustable pass part may extend out from the active part and support a handle portion of the surface processing equipment and a control interface which an operator can use to 25 interact with the surface processing equipment. The adjustable mass part can also be slidingly connected to the active part in order to move along a track or some sort, such as in a straight line or along a curved track. In this case the at least one actuator can comprise a linear actuator such as a rack and pinion arrangement or a hydraulic piston arranged to control the position of the adjustable mass 30 part along the track in dependence of the control signal from the control unit. The control unit may comprise a first record where data indicative of a desired tool pressure and / or desired state of the at least one actuator for one or more surface processing operations, one or more surface materials, and / or for one or more tool types is stored. The 2026200332   11 Jun 2026 control unit can access the data in this record in order to obtain information related to the desired tool pressure and / or the desired state of the actuator for a given surface processing operation and / or for a given tool type. This way the control unit can automatically configure applied tool pressure in response to input of the type of surface processing operation to be 5 performed and / or the tool type in use, thereby reducing the requirements on operator experience. In other words, the control unit can be configured to obtain data, e.g., via a control interface, indicative of a current surface processing operation to be performed by the surface processing equipment and to obtain the desired tool pressure and / or desired state of the at least one actuator from the first record in dependence of the current surface 10 processing operation. The control unit can also be adapted to automatically detect which type of tool that is currently attached to the tool carriers of the surface processing equipment and subsequently obtain the desired tool pressure and / or state of the at least one actuator from the first record in dependence of the detected type of tools. This way the applied tool pressure can be configured in an automated manner with a reduced need for manual 15 configuration of the surface processing equipment. The control unit may also comprise a second record where data indicative of an applied tool pressure as function of the state of the at least one actuator is stored and accessible by the control unit functions. The control unit can then be configured to obtain the current tool pressure from the second record as function of the current state of the at least one actuator. 20 In other words, the second record is a mapping between the actual applied tool pressure and position of the adjustable weight part (determined by the state of the actuator). Among other things, this allows the control unit to display the currently applied tool pressure on a display device of the surface processing machine in dependence of the state of the actuator. This also allows the control unit to configure the state of the actuator in order to obtain a 25 desired tool pressure. In other words, the second record allows the control unit to translate back and forth between the position of the adjustable mass part in relation to the other parts of the surface processing equipment and applied tool pressure, which can be convenient in many different applications including both control applications and for information purposes. It is appreciated that the first record and / or the second record can be located remotely from 30 the surface processing equipment, such at a remote server, in a remote control device of the surface processing equipment, or locally in a digital storage device onboard the surface processing equipment. 2026200332   11 Jun 2026 A potential risk associated with use of the adjustable mass part is that the surface processing equipment tips over inadvertently as a result of changing the position of the adjustable mass part too much. The risk may be especially pronounced when the surface has a significant slope. To mitigate this risk, the control unit can be configured to obtain 5 data indicative of a slope of the surface relative to a horizontal plane, and to limit the state of the actuator, such as the tilt angle of a tilt actuator, to be within a stability range configured at least in part in dependence of the slope of the surface. The stability range can be preconfigured as a function of the surface slope angle, in order to ensure that the surface processing equipment does not tip over. The surface slope angle can be measured by, e.g., 10 an electronic spirit level or the like. The control unit can of course also be configured to limit the actuator state to be within a slope-independent predetermined stability range in case no electronic spirit level or other slope sensor is mounted on the surface processing equipment. The control unit can also use the slope data to adjust the position of the adjustable mass part to maintain a constant applied tool pressure measured in a direction 15 normal to the surface as the slope of the surface changes. Without this type of control, the applied tool pressure measured normal to the surface is likely to change if the slope of the surface changes during the surface processing operation. The slope data can for instance be included in the first and / or in the second record. The first record then maps desired tool pressure and / or desired state of the at least one actuator for one or more surface processing 20 operations, one or more surface materials, and / or for one or more tool types and / or for different surface slopes. The second record then maps applied tool pressure as function of the state of the at least one actuator and as function of the current slope of the surface that is processed. According to other preferred aspects, the control unit is adapted to measure a dust 25 generation rate of the tools of the equipment in use and to adjust the state of the at least one actuator to reduce a difference between a current dust generation rate and a desired dust generation rate. Many surface processing operations, such as floor grinding, generate an amount of dust during the operation. The amount of generated dust should not be too high nor too low, and the desired dust generation rate is often known beforehand. The 30 applied tool pressure normally has an effect on the amount of generated dust, measured, e.g., as a dust generation rate in terms of weight of dust generated per unit of time. The applied tool pressure can be automatically adjusted by the control unit in order to optimize performance of the surface processing operation, by monitoring the dust generation rate and adjusting tool pressure until the dust generation rate is as intended for the given 35 operation. The applied tool pressure can for instance be swept up and down while the dust 2026200332   11 Jun 2026 generation rate is monitored. A suitable applied tool pressure can then be selected by setting the actuator state at the value that generated the dust generation rate closest to the desired dust generation rate for the surface processing operation and / or for the tool type in use. The preferred dust generation rate for a given operation may also be configured as a 5 function of tool wear. A surface processing operation can often be finished faster, at the expense of an increased tool wear. Thus, the operator may configure a desired tool wear, such as a selection from aggressive to less aggressive, and the control unit will then take this setting into account when configuring the desired tool pressure. WO2022132020A1 describes some example dust extractors capable of measuring the weight of extracted dust 10 over time. The control unit can also be adapted to measure a load or weight on the tools supported by the tool carriers, e.g., by using one or more load cells and / or strain gauges arranged in connection to the tools, and to adjust the state of the at least one actuator to reduce a difference between a current load on the tools and a desired load on the tools. This is a 15 more direct and robust way of adjusting applied tool pressure in an automated manner. The control unit can for instance use a record such as the first record mentioned above in order to determine the desired tool pressure to be applied for a given surface processing operation and / or tool type, and then adjust the state of the actuator until the measured load on the tools matches the desired tool pressure. The one or more load cells and / or strain 20 gauges can be used as a complement to the second record. The control unit can furthermore be adapted to monitor one or more characteristics of a winding current associated with one or more drive motors of the equipment and to adjust the state of the at least one actuator to reduce a difference between current winding current characteristics and desired winding current characteristics. A winding current is an electrical 25 current propagating in a stator to drive an electric motor of the equipment. The characteristics of the winding currents may simply be a consumed power or drive current magnitude of the one or more drive motors of the surface processing equipment. The control unit then adjusts the state of the actuator and thus also the position of the adjustable mass part to obtain a desired consumed power. According to a straight forward example, 30 the control unit knows which power consumption to expect for a correctly configured applied tool pressure, and adjusts the position of the adjustable mass part until this power consumption is also seen. The desired consumed power can be a preconfigured value selected in dependence of the type of surface processing operation to be performed and / or the type of tools in use. This type of function can also be advantageously implemented 2026200332   11 Jun 2026 using a function based on machine learning techniques, which will be discussed in more detail below. The machine learning function can for instance monitor the actual winding currents of the electric drive motors of the surface processing equipment and adjust the actuator state (and thereby the applied tool pressure) until the characteristics of the winding 5 current, in particular the back-EMF, matches the desired winding current characteristics. The control unit can also use recordings of sound generated by the surface processing equipment in use to optimize the state of the actuator, as will be discussed in more detail below. The applied tool pressure is an important parameter in many surface processing operations. 10 Additional parameters that may have an effect on the efficiency of the surface processing operation and / or on the quality of the end result of the surface processing operation are the rotation speed of the one or more tool carriers about one or more axes of rotation and the speed of one or more traction wheels of the surface processing equipment in combination with control of the state of the at least one actuator. These two parameters can be controlled 15 by the control unit in combination with the tilt angle in order to optimize performance of the surface processing operation. The first record can, for instance, be expanded to also provide data related to a desired rotation speed of the active part, and / or a desired drive wheel speed of the surface processing equipment. The control unit can furthermore be adapted to control a speed of one or more traction wheels of the surface processing 20 equipment in combination with control of the state of the at least one actuator. The present disclosure also provides surface processing equipment for processing a surface. The equipment comprises an active part, an adjustable mass part, a support arrangement, and a control unit. The active part comprises one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an 25 applied tool pressure. The support arrangement is connected to the active part and adapted to support the floor grinder on the surface. The adjustable mass part is connected to the active part and associated with at least one actuator that is adapted to cause movement of the adjustable mass part in response to a control signal as discussed above. The control unit is configured to control a state of the at least one actuator during rotating engagement 30 between the one or more tool carriers and the surface. In other words, the control unit adjust the tilt angle or position of the adjustable mass part along the track while the tools are rotating, i.e., during the surface processing operation. This way the surface operation can be made more efficient, and / or the end result of the surface processing operation improved, since the applied tool pressure is adjusted as the tools engage the surface, whereby the 2026200332   11 Jun 2026 immediate effect of the tool pressure adjustment on the performance of the equipment can be observed in real-time. The current tool pressure can also be adjusted by moving one or more support members relative to the active part in order to adapt the applied tool pressure, and also by adjusting 5 the position or positions of the tool carriers relative to the surface to be processed. The surface processing equipment may comprise actuators configured to control a position of one or more support members, such as wheels, and / or actuators configured to control positions of the tool carriers relative to the surface. This way applied tool pressure can be controlled in an automated manner by the control unit using control signals sent to the 10 different actuators. There is also disclosed methods, computer programs, computer readable media, and computer program products associated with the above discussed advantages. Advantageously, embodiments of the invention may provide improved floor grinders and other types of surface processing equipment suitable for manual operation , autonomous 15 operation and / or semi-autonomous operation. Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a / an / the element, apparatus, component, means, step, etc." are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, 20 etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated. Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the following description. The skilled person realizes that different features of the present invention may be combined to create embodiments other than those 25 described in the following, without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS With reference to the appended drawings, below follows a more detailed description of embodiments of the invention cited as examples. In the drawings: 30 Figure 1      shows example surface processing equipment on a concrete surface; 2026200332   11 Jun 2026 Figure 2 illustrates example tool holders and support wheels on a floor grinder; Figures 3A-C show floor grinders configured with different tool pressure values; Figure 3D illustrates a rotary actuator on surface processing equipment; Figures 4A-C show example surface processing equipment. 5 Figure 5 schematically illustrates a tool pressure control architecture; Figures 6-8 show example surface processing equipment on a concrete surface; Figure 9 schematically illustrates adjustment of tool carriers; Figure 10 is a flow chart illustrating a method; and Figure 11 schematically illustrates a control unit. 10 DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION The invention will now be described more fully hereinafter with reference to the accompanying drawings, in which certain aspects of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited 15 to the embodiments and aspects set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout the description. It is to be understood that the present invention is not limited to the embodiments described 20 herein and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the appended claims. Figure 1 illustrates an example floor grinder for processing a surface 101, such as a concrete surface, a floor, or a dirt surface. The floor grinder is an example of surface processing equipment 100 that can be used to even out, grind, polish and / or clean a 25 concrete surface, a stone surface, or some other hard material surface such as a linoleum floor or the like. The different aspects and technical teachings of the present disclosure will be described using a floor grinder as an example. It is, however, appreciated that the 2026200332   11 Jun 2026 teachings are generally applicable to other types of surface processing equipment such as power trowels, floor polishing equipment, and floor cleaning equipment. The surface processing equipment 100 comprises an active part 110 that is arranged to engage the surface 101 in order to process the surface in some way. The active part of the 5 equipment may comprise, e.g., grinding tools, screeds, or polishing pads which are normally rotated relative to the surface that is being processed. The grinding tools may comprise diamond-based abrasives, carbide-based abrasives, or other types of abrasives. Polishing pads used on surface processing equipment of the type discussed herein may be adapted to absorb a polishing compound. 10 The floor grinder 100 in Figure 1 also comprises an adjustable mass part 120, a support arrangement 130, and a control unit 140. In this example the adjustable mass part 120 forms part of the main body of the equipment together with the active part 110, as will be illustrated in more detail below in connection to Figures 3A-C. However, the adjustable mass part may also comprise separate weights pivotably and / or slidingly attached to the 15 active part. The active part 110 supports the tools and drives the tools by one or more drive motors 180, 185 arranged to rotate the tools. The drive motors on a floor grinder are often electric motors, although combustion engine powered surface processing equipment is also known. The tools and techniques disclosed herein are applicable with both electrically powered and 20 combustion engine powered machines. The drive arrangement on the surface processing equipment may also be a hybrid drive arrangement that comprises both a combustion engine and an electric motor. In case of electric drive, one or more motor drivers forming part of a power electronics part of the surface processing equipment 100 provides drive currents to the electric drive motors 25 of the equipment 100. The power consumption of the drive motors as well as the magnitude and relative phases of the drive currents can be monitored by the control unit, as will be discussed in more detail below. Parts or all of this data can, for instance, be readily available over a Controller Area Network (CAN) bus of the surface processing equipment 100. The support arrangement 130 is connected to the active part 110, e.g., via a chassis or 30 body frame of the surface processing equipment 100, and adapted to at least partly support the floor grinder 100 on the concrete surface 101. The equipment 100 is thus partly supported on the surface 101 by the tools of the active part 110 and partly by the support arrangement 130. The example support arrangement illustrated in Figures 1-2 comprises 2026200332   11 Jun 2026 support wheels associated with a wheel axle 135 that extends transversally to a forward direction F of the equipment. The support wheels may be driven wheels, in which case the support wheels can be referred to as traction wheels of the surface processing equipment 100. The support wheels can be adapted to move relative to the active part, as will be 5 discussed below in connection to Figure 7. The support arrangement 130 may also comprise additional support wheels located in front of the surface processing equipment and / or at the sides of the surface processing equipment. A machine having such support wheels will be discussed below in connection to Figure 8. 10 The adjustable mass part 120 in the example of Figure 1 can form a part of the main equipment body that extends out from the active part 110 and up above the active part 110 as illustrated in Figure 1. According to other examples the adjustable mass part 120 is a separate part that is pivotably arranged in relation to the active part 110. These types of machines will be discussed in connection to Figures 4A-C. The adjustable mass part 120 15 may also be slidingly arranged in relation to the fixed part, such that it can slide along a straight or curved track 600 on the surface processing equipment 100. An example of a machine comprising this type of adjustable mass part will be discussed in connection to Figure 6. The surface processing equipment 100 normally comprises an onboard control unit 140 20 which is only schematically illustrated in Figure 1, and possibly also a handle portion that can be used to guide the surface processing equipment 100 on the surface 101. A display unit may also be arranged on the equipment 100 in order to communicate information to an operator and also to receive input commands and configuration data from the operator. A part of the main body of the equipment 100 which forms an adjustable mass part 120 25 normally also comprises power electronics and optionally also a battery or other electrical energy storage device. This body part may be formed in steel or other mechanically robust material and is therefore of considerable weight. The surface processing equipment 100 may be controlled from a distance by a remote control device 155 which is arranged to communicate 151 wirelessly or over a wired 30 communication channel with the control unit 140 onboard the surface processing equipment 100. The remote control device 155 comprises a control unit 150 which may be adapted to control one or more operations of the surface processing equipment 100. The operator using the remote control device 155 may be located in vicinity of the equipment 100, such 2026200332   11 Jun 2026 as within 10-50 meters, or more remotely, such as several miles away from the equipment 100. One or both control units 140, 150 may be arranged to maneuver the surface processing equipment 100 on the surface 101 during a surface processing operation. The control units 5 140, 150 may support autonomous operation of the equipment 100 using techniques known in the art. Manual or semi-autonomous operation of the surface processing equipment 100 is also possible. The control unit 140 onboard the surface processing equipment 100 and / or the control unit 150 of the remote control device 155 may be adapted to communicate 165 with a wireless 10 access point 160 over a radio link 165, such as a cellular radio link, a Wi-Fi radio link, or some other wireless access system. The wireless access point 160 may be connected to a remote server 170. The remote server 170 may comprise data such as configuration data and software that can be downloaded to the surface processing equipment 100 and / or to the remote control device 155. The software on the remote server 170 can also be executed 15 remotely on the server to control one or more functions and operations of the surface processing equipment 100. A wireless device 156 can be connected to the onboard control unit 140 and used to configure one or more parameters of the surface processing equipment 100, as well as to communicate information to an operator of the equipment 100. 20 Figure 2 shows a bottom view of an example active part 110 and a support arrangement 130 of a floor grinder. The active part 110 comprises tool carriers 210 that are arranged to hold tools configured to rotatably engage a surface 101 such as a concrete surface. The example active part 110 illustrated in Figure 2 is often referred to as a planetary head and it rotates about a center axis 220 while the tool carriers 210 also rotate about respective 25 tool carrier axes 230. The tool carriers 210 extend in a tool carrier plane. The alignment of the tool carrier plane in relation to the surface 101 has an effect on the operation of the surface processing equipment 100. According to some aspects the equipment 100 comprises tool carrier adjustment actuators adapted to control the geometrical relation between the tool carrier plane and the surface in terms of the angle of the tool carrier plane 30 relative to the surface. An example of surface processing equipment comprising such tool carrier adjustment actuators will be discussed below in connection to Figure 9. 2026200332   11 Jun 2026 Figure 2 also shows an example support wheel axle 135. A forward direction F of the surface processing equipment extends parallel with the wheel planes W1, W2, and orthogonally to the support wheel axle 135. A reverse direction R of the surface processing equipment is opposite to the forward direction F. 5 An important parameter when processing a surface such as a concrete or stone surface by, e.g., a floor grinder or other type of surface processing equipment is the pressure that is applied to the tools that engage the surface. Applied tool pressure is also important when trowelling a fresh or maturing concrete surface, and when polishing a surface such as a floor. This pressure is referred to herein as the applied tool pressure, and it can be quantified 10 by the normal force in Newtons (N) acting on the tools as they are pressed against the surface 101. It is also possible to quantify the applied tool pressure as force per tool area unit, i.e., in N / m2 or as a pounds per square inch (psi) value. Known surface processing equipment 100 comprises adjustable weights which can be manually moved relative to the active part in order to adjust tool pressure. However, this only allows the applied tool 15 pressure to be adjusted in rather coarse steps, and the adjustment is manual in the sense that an operator moves the weights by hand to adjust applied tool pressure. Some surface processing equipment also comprises actuators configured to move adjustable mass parts on the surface processing equipment, but these actuators are manually controlled by an operator and not configured to be automatically adjusted during use of the equipment. 20 The present disclosure relates to surface processing equipment capable of automated control of the applied tool pressure. With reference to Figures 3A-D, the adjustable mass part 120 may form a part of the main body of the equipment 100 that is pivotably connected to the active part 110 such that it can rotate about a pivot axis 310. The pivot axis 310 extends transversally to the forward direction F of the surface processing equipment 100. 25 The pivot axis 310 is often parallel or at least approximately aligned with the wheel axle 135 shown in Figure 2. At least one actuator 300 is connected between the active part 110 and the adjustable mass part 120. The at least one actuator 300 is in this example adapted to control a tilt angle 320 between the active part 110 and the adjustable mass part 120 about the pivot axis 310, 30 thereby controlling a position of the adjustable mass part 120 in relation to the support arrangement 130 and in relation to the active part 110. A tilt actuator of the kind illustrated in Figures 3A-C can be a linear actuator such as a hydraulic piston or an electric linear actuator such as an electric motor combined with a rack and pinion arrangement. The 2026200332   11 Jun 2026 actuator 300 can also be realized as a rotary actuator arranged to directly generate rotation by the adjustable mass part 120 about the pivot axis 310. Example rotary actuators that can be applied are slew drives and worm gear arrangements. Figures 3A-D show example surface processing equipment 100 where the adjustable mass 5 part 120 forms part of the main body of the equipment 100. Figures 4A-C show example surface processing equipment 100 where the adjustable mass part 120 comprises at least one separate weight which is pivotably attached to the active part 110 of the surface processing equipment 100. Figure 6 shows example surface processing equipment 100 where the adjustable mass part is instead arranged to slide along a track 600 on the 10 equipment. All the different adjustable mass parts described herein can be freely combined, i.e., surface processing equipment 100 may comprise both a pivotable weight and a sliding weight, and possibly also adjustable support wheels. The control unit 140 on the surface processing equipment 100 and / or the control unit 150 in the remote control device 155 is operably connected to the at least one actuator 300 and 15 configured to control the state of the actuator with the target to optimize performance of the surface processing equipment 100. Maximum applied tool pressure is obtained when the handle part is not tilted at all relative to the chassis part, as shown in Figure 3A. The mass center 125 is then moved as far in the forward direction F as possible. The smallest (nonzero) applied tool pressure is obtained just as the machine starts to tip over in the reverse 20 direction R, i.e., when the mass center 125 of the adjustable mass part 120 balances the mass center 115 of the active part 110 over the support arrangement 130. The tip over direction is indicated by the arrow T in Figure 3D. The support arrangement 130 functions as a fulcrum about which the masses 115, 125 of the active part 110 and the adjustable mass part 120 interact. The relative locations of the mass centers 115, 125 of the active 25 part 110 and the adjustable mass part 120 in relation to the support arrangement 130 determine the applied tool pressure F1, F2, F3. A thicker arrow F1 indicates a larger applied tool pressure and a thinner arrow F3 indicates a smaller applied tool pressure in Figures 3A-D. Herein, the state of an actuator adapted to control the position of an adjustable mass part 30 refers to the current configuration of the actuator, such as the current angle of a tilt actuator or the current extension length of a linear actuator. The state of an actuator may also refer to a currently applied force, a current configuration command sent to the actuator, or the like. More generally, the state of an actuator used to control the position of an adjustable 2026200332   11 Jun 2026 mass part indicates the position of the adjustable mass part in relation to one or more other parts on the surface processing equipment. The state of the actuator governs the position of the mass center of the adjustable mass part, and therefore at least partly determines the applied tool pressure. The applied tool pressure can be adjusted by the control unit by 5 controlling the state of the actuator. Controlling the state of the actuator may comprise sending one or more control signals directly to the actuator, or to some intermediary control system which is controllably coupled to the actuator. The distance from the mass centers 115, 125 to the fulcrum point of the support arrangement of course depends on the type of surface processing equipment. The control 10 unit 140, 150 can be configured with a model of how the balancing forces develop as function of tilt angle 320, and what effect a given tilt angle has on the applied tool pressure. This model can also be set up to account for the slope of the surface 101 relative to the horizontal plane. The gravitational pull on an object is given by the product of mass m and gravitational acceleration g. The moment or torque about the contact area 301 between the 15 support arrangement and the surface 101 (which acts as fulcrum) determines the applied tool pressure. The moment is given by the product of force and the length of the lever arm. At equilibrium, the applied tool pressure is zero and the mass center 115 of the active part 110 balances the mass center 125 of the adjustable mass part 120. At this point, the magnitude of the moment generated by the gravitational pull on the active part is the same 20 as the magnitude of the gravitational pull on the adjustable mass part but with a different sign. Any further increase in tilt angle beyond the balancing point will cause the surface processing equipment 100 to tip over in direction of the arrow T. In the example of Figure 6 the adjustable mass part 120 is slidingly connected to the active part 110 and adapted to move in relation to the support arrangement 130 and in relation to 25 the active part 110. The at least one actuator 300 comprises an actuator such as a linear actuator that is arranged to control the position of the adjustable mass part 120 in dependence of the control signal from the control unit 140, 150, 170. By moving the weight of the adjustable mass part 120 around on the surface processing equipment, the applied tool pressure can be adapted by the control unit using a control signal to control a state of 30 the actuator. When the weight of the adjustable mass part is located over the support arrangement 130 the applied tool pressure is lower compared to when the weight of the adjustable mass part 120 is located over the tool carriers on the active part 110. The track which the weight is moved along may be a straight track as shown in Figure 6, or a curved track that extends on the surface processing equipment. There can be one or more 2026200332   11 Jun 2026 adjustable weight parts, such as one adjustable weight part on either side of the surface processing equipment 100. Equipment 100 comprising two adjustable mass parts arranged on opposite lateral parts of the surface processing equipment 100 is shown in Figure 4C. The control unit 140 on-board the surface processing equipment 100, and / or the control 5 unit 150 in the remote control device 155, and / or the wireless device 156, and / or the remote server 170 is configured to obtain data indicative of a desired tool pressure and to control a state of the at least one actuator 300 to reduce a difference between a current tool pressure and the desired tool pressure. Thus, an automated control of applied tool pressure is obtained. The automated adjustment of tool pressure can be made with fine resolution, 10 since the adjustment of actuator state (such as tilt angle) can be made continuously or at least in very small steps, which is an advantage. The automated adjustment of tool pressure can also be made during operation of the surface processing equipment 100, i.e., as the tools actively engage the surface 101, which is an advantage since this means that the efficiency of the surface processing operation can be monitored in real-time and the applied 15 tool pressure can be adjusted in order to maintain efficient operation. Efficiency of a surface processing operation can be measured, e.g., in terms of the time it takes to complete a given surface processing task, in terms of tool wear, or in terms of energy consumption of the surface processing equipment. The applied tool pressure can be adjusted to improve any one of these efficiency metrics or a combination of two or more 20 efficiency metrics. A surface processing operation can sometimes be finished faster if the surface processing equipment is used more aggressively, but at the expense of increased tool wear and increased power consumption. The control unit can be configured to control the applied tool pressure in dependence of a preferred level of aggressiveness. The operator can for instance configure the wanted level of aggressiveness using a control input 25 interface, and the control unit can then adjust the applied tool pressure by controlling the position of the adjustable mass part to obtain the configured level of aggressiveness. The quality of the end result of the surface processing operation performed by the surface processing equipment can be measured in terms of the properties of the processed surface, such as if there are scratch marks in the surface after processing, if the desired surface 30 level was obtained, if the surface gloss is as intended, and so on. The surface processing equipment 100 can automatically use the at least one actuator 300 to adjust the applied tool pressure, e.g., in dependence of the type of tool in use, the work task to be performed, properties of the surface 101 that is processed, the desired level of 2026200332   11 Jun 2026 aggressiveness of the surface processing operation to be performed, or other operating conditions. This means that the requirements on the experience and competence of the operator is reduced, since the surface processing equipment is capable of automated configuration of applied tool pressure. 5 To summarize, there is disclosed surface processing equipment 100, such as a floor grinder, a power trowel, a floor polishing machine, or a floor cleaning machine, for processing a surface 101. The equipment 100 comprises an active part 110, an adjustable mass part 120, a support arrangement 130, and a control unit 140, 150, as discussed above. The active part 110 comprises one or more tool carriers 210 that are arranged to 10 support respective tools configured to rotatably engage the surface 101 at an applied tool pressure. The tools may, e.g., be abrasive tools such as diamond tools, trowel tools, or polishing pads. The tools are pressed down against the surface to be processed and rotated relative to the surface. In the case of a floor grinder, this rotation removes material from the surface 101. In the case of a trowel the rotation evens out the surface, and in the case of a 15 polishing machine the rotation polishes and / or cleans the surface. The force at which the tool is pressed against the surface is referred to herein as the applied tool pressure, which is a force normal to the surface 101 measured, e.g., in Newtons. The applied tool pressure should neither be too low nor too high. A too low tool pressure often reduces the efficiency of the surface processing operation. A too high applied tool pressure may also reduce the 20 efficiency of the surface processing operation, and may also damage the surface, i.e., reduce the quality of the end result. The support arrangement 130 is connected to the active part 110 and adapted to at least partly support the floor grinder 100 on the surface 101. The support arrangement 130 can for instance comprise wheels as illustrated in Figures 1-2, a support roller, tracks, or some 25 other type of surface support. The surface processing equipment 100 in use is supported on the surface 101 in part by the tools on the tool carriers 210 and in part by the support arrangement 130. The adjustable mass part 120 may be pivotably connected to the active part 110 to rotate about a pivot axis 310 as illustrated in Figures 3A-D and in Figures 4A-C, or slidingly 30 connected to the active part in order to move relative to the active part as schematically shown in Figure 6. According to a first example illustrated in Figures 3A-D the adjustable mass part 120 forms part of the main body of the surface processing equipment 100 which is tilted away from 2026200332   11 Jun 2026 the active part 110. In this case the adjustable mass part 120 may also support a handle portion of the surface processing equipment and possibly also a display unit as well as control input means such as buttons, knobs or a touch screen, that an operator can use to input and adjust configuration parameters of the equipment 100. 5 The example equipment 100 in Figures 4A-C comprises a handle portion 400 that can be used by an operator to guide the equipment. The equipment 100 in Figures 4A-C can also be autonomously directed on the surface, or operate in a semi-autonomous mode of operation where the operator controls one or more functions, but does not guide the equipment fully. The handle portion 400 has been folded in over the active part 110 in Figure 10 4C. The adjustable mass part 120 in Figures 4A-B and 4C comprises a first adjustable mass part 120a and a second adjustable mass part 120b arranged to rotate about respective pivot axes 310. In this case the two pivot axes are aligned with each other, but they can also be somewhat offset. Respective actuators 300 are connected between the active part 15  110 and the adjustable mass parts 120a, 120b. The actuators are adapted to control the tilt angles 320 of the adjustable mass part about their respective pivot axes 310. The actuators 300 shown in Figures 4A-B are based on hydraulic pistons, but other types of linear actuators or rotary actuators can also be used to adjust the tilt angles 320 of the mass parts 120a, 120b. 20 The first adjustable mass part 120a and the second adjustable mass part 120b are preferably separated by a plane P extending traversal to the pivot axes 310. In other words, the first adjustable mass part 120a and the second adjustable mass part 120b are arranged on either side of the equipment 100. This means that the control unit 140, 150 can use the mass parts to balance the equipment laterally on the surface, in order to optimize the 25 performance of the equipment. This use of two or more adjustable mass parts distributed over the surface processing equipment can be used with other types of weights and with other types of actuators, as will be appreciated by the skilled person. The rotation of the adjustable mass part 120 about the pivot axis 310 or axes 310 is such as to change a horizontal distance between a mass center 125 of the adjustable mass part 30 120 and the support arrangement 130 as discussed above. With reference to Figures 3A- C, when the mass center of the adjustable mass part 120 is to the left of the contact area 301 between the support arrangement 130 and the surface, then the weight of the adjustable mass part increases the applied tool pressure F1. The further to the left the 2026200332   11 Jun 2026 adjustable mass part is rotated the higher the applied tool pressure becomes. If the adjustable mass part is instead rotated such that the mass center 125 of the adjustable mass part is to the right of the support arrangement 130 then the applied tool pressure F3 decreases. If the mass center 125 of the adjustable mass part 120 is directly above the 5 contact area 301 between the support arrangement 130 and the surface 101, then the mass of the adjustable mass part is fully supported by the support arrangement 130. Note that “left” in Figures 3A-D corresponds to the forward direction F of the equipment 100, and that “right” in Figures 3A-D corresponds to a reverse direction R of the equipment, which is opposite to the forward direction, as indicated in Figures 3A-D. The contact area 131 10 between the surface 101 and the support arrangement 130 acts as a fulcrum to the mass center 115 of the active part 110 and the mass center 125 of the adjustable mass part 120, at least when the adjustable mass part has been rotated past a vertical plane intersecting the contact area 301 between the surface 101 and the support arrangement 130. If the adjustable mass part 120 has sufficient weight and / or is rotated far enough to the right 15 in Figures 3A-C, then the surface equipment 100 may tip over in direction of the arrow T. An actuator 300 can be connected between the active part 110 and the at least one adjustable mass part 120, 120a, 120b and adapted to control the tilt angle 320 between the active part 110 and the adjustable mass part 120 about the pivot axis 310, thereby controlling a position of the mass center 125 of the adjustable mass part 120 in relation to 20 the support arrangement 130 and in relation to the mass center 115 of the active part 110. The control unit 140, 150 is configured to control a state of the actuator 300 to reduce a difference between a current tool pressure and a desired tool pressure. Figure 6 shows an example of surface processing equipment 100 where the adjustable mass part 120 is a weight that is arranged to move along a track in the longitudinal direction 25 of the equipment 100. The control unit controls an actuator, such as a rack and pinion arrangement, a belt and pulley arrangement, or a hydraulic piston which moves the weight closer or further away from the rear support wheels 130. This adjusts the applied tool pressure. There may be one or more such movable weights on the surface processing equipment. It may be an advantage to mount one movable weight on either side of the 30 machine, since then the lateral tool pressure distribution can also be controlled by the control unit by adjusting the left and the right weight independently. It is also possible to mount the weight on a curved track, such as a circular track extending around the drive motor 180. 2026200332   11 Jun 2026 The control unit 140, 150 is advantageously configured to control a state of the actuator 300 during rotating engagement between the one or more tool carriers 210 and the surface 101. This feature of the control unit 140, 150 is not inextricably linked to any of the other features of the control unit discussed herein, but can be implemented as a separate feature. 5 By controlling the state of the actuator 300 during rotating engagement between the one or more tool carriers 210 and the surface 101, as opposed to adjusting the position of the adjustable mass part when the machine is not operating, it is possible to observe the effect of a change in weight distribution in real time. The position of the adjustable mass part can be optimized by varying the position while monitoring one or more effects of the adjusted 10 position, such as a dust generation rate, a power consumption, winding current characteristics of the drive motors, a vibration, a temperature, or some other performance metric. The actuator 300 can for instance be a linear actuator such as a hydraulic piston, a pneumatic piston, a belt and pulley arrangement, or a rack and pinion arrangement, which 15 is arranged to control the tilt angle 320 or position of the weight along the track 600 in dependence of a control signal from the control unit 140, 150. By extending a linear actuator as illustrated schematically in Figures 3A-C, the tilt angle 320 can be adapted with high accuracy. The position of the weight along the track 600 can also be controlled with high accuracy by a linear actuator. 20 The actuator 300 can also be a rotary actuator that is arranged to control the tilt angle 320 in dependence of a control signal from the control unit 140, 150. Example rotary actuators that can be used in this application comprise slew drives, worm gear arrangements, and the like. The control unit 140 onboard the surface processing equipment 100 may be arranged to 25 control the actuator or actuators by transmitting messages over a controller area network (CAN) bus to the actuator, and optionally also receiving feedback messages from the actuator 300 that indicates a state of the actuator 300, such as the current tilt angle, and also error messages indicative of malfunction of the actuator 300. The state of the actuator 300, such as the current tilt angle, can be determined using one or more sensors such as 30 actuator position sensors. The control unit 140 can also store one or more states of the actuator 300. This means that the control unit 140 can be configured to remember one or more previous actuator states, and also revert back to a previous actuator state stored in 2026200332   11 Jun 2026 the memory. An operator can manually trigger storing of a current state of the actuator 300, and later on retrieve the state in case the same setting is desired at a future point in time. Figure 7 and Figure 8 show an alternative or complementary embodiment of the automated tool pressure techniques discussed herein. According to these examples the applied tool 5 pressure is adjusted by moving the support members around on the surface 101. In Figure 7 the wheel axle 135 is shifted longitudinally, i.e., in direction of the wheel planes W1, W2 by an actuator controlled by the control unit 140, 150. By extending and retracting the wheelbase of the surface processing equipment in this manner the applied tool pressure can be adjusted. In Figure 8 a number of additional support wheels 810, 820 have been 10 mounted on the surface processing equipment 100. Each support wheel is controllable by the control unit such that it can be moved vertically and / or horizontally by the control unit. By moving the support wheels vertically the support wheels bear more or less of the weight of the surface processing equipment 100. By moving the support wheels horizontally, the balance of the surface processing equipment changes. This way the control unit can shift 15 applied tool pressure both laterally and longitudinally, i.e.,, to increase or decrease tool pressure at one side, at the front, or at the back of the active part 110. The applied tool pressure can be adjusted during operation or when the equipment is stationary. Figure 9 shows an example where the active part 110 comprises tool carrier adjustment actuators 900 adapted to control a relative orientation of the tool carrier plane and the 20 surface 101. The tool carrier adjustment actuators 900 can also be used to raise and to lower the active part relative to the surface. The control unit can shift applied tool pressure to the sides of the equipment and in the forward / reverse direction, depending on the preferred weight distribution of the surface processing equipment 100. The examples illustrated in Figure 7 and in Figure 8 are not inextricably linked to the other 25 example equipment described herein. Figure 8 shows surface processing equipment 100 for processing a surface 101. The equipment 100 comprises an active part 110, a support arrangement 130, and a control unit 140, 150, 170. The active part 110 comprises one or more tool carriers 210 arranged to support respective tools configured to rotatably engage the surface 101 at an applied tool pressure. The support arrangement 130 is connected to 30 the active part 110 and adapted to support the floor grinder 100 on the surface 101. In the example of Figure 8, the support arrangement 130 comprises at least one support wheel actuator 700, 800 that is adapted to control a vertical and / or horizontal position of at least one support wheel 130, 810, 820 of the support arrangement 130 in response to a control 2026200332   11 Jun 2026 signal. The control unit 140, 150, 170 is configured to control a state of the at least one support wheel actuator 700, 800 by the control signal to reduce a difference between a current tool pressure and a desired tool pressure. The example illustrated in Figure 9 is also not inextricably linked to the other example 5 equipment described herein. Figure 9 shows surface processing equipment 100 for processing a surface 101. The equipment 100 comprises an active part 110, a support arrangement 130, and a control unit 140, 150, 170. The active part 110 comprises one or more tool carriers 210 arranged to support respective tools configured to rotatably engage the surface 101 at an applied tool pressure. The one or more tool carriers 210 extend in a 10 tool carrier plane, as exemplified in Figure 2 and discussed above. At least one tool carrier adjustment actuator 900 is adapted to control a pose 910 of the active part 110 relative to the surface 101 in response to a pose control signal. A tool carrier adjustment actuator may for instance be connected to a tool carrier 210 in order to adjust a vertical position of the tool carrier. It is also possible to attach the actuators to the planetary head of the surface 15 processing equipment in order to adjust the angle of the tool carrier plane relative to the surface 101. This way the control unit can shift applied tool pressure laterally to one side or longitudinally to the front or rear of the equipment. The control unit 140, 150, 170 is configured to control the at least one tool carrier adjustment actuator 900 by the pose control signal to reduce a difference between a current pose and a desired pose. 20 Figure 5 shows an example tool pressure control architecture 500 which can be used to adjust the state of the at least one actuator 300 in an automated manner. The architecture 500 comprises the control unit 140 onboard the surface processing equipment 100 and / or the control unit 150 in the remote control device 155, and / or the remote server 170 discussed above in connection to Figure 1. The control unit 140, 150, 170 is adapted to 25 receive one or more input signals 510-550 from external data sources. The different input signals are all indicative of the efficiency of the surface processing operation or the state of the surface processing equipment 100 in some way, and the control unit 140, 150, 170 is configured to use these input signals together with a function 560 to generate the control signal 590 which adjusts the state of the at least one actuator 300. Thus, automated control 30 of applied tool pressure is provided by the control architecture 500. The control unit 140, 150, 170 optionally comprises a first record 570 of data indicative of a desired tool pressure and / or desired state of the at least one actuator 300 for one or more surface processing operations, one or more surface materials, and / or for one or more tool 2026200332   11 Jun 2026 types. This means that an operator can simply input the surface processing operation to be performed on the surface 101 and / or the tool type to be used, such as the grit of a floor grinding tool type in use or a polishing pad compound or pad dimension in use. The control unit 140, 150, 170, having access to the first record 570 can look up the correct tool 5 pressure and / or desired state of the at least one actuator 300, and adapt the control signal 590 accordingly. In other words, the control unit 140, 150, 170 can be configured to obtain data indicative of a current surface processing operation to be performed by the surface processing equipment 100, e.g., via manual input from the operator or by downloading a work specification from the remote server 170, and subsequently obtain the desired tool 10 pressure and / or desired state of the at least one actuator 300 from the first record 570 in dependence of the current surface processing operation to be performed. According to another example, the control unit 140, 150, 170 is adapted to automatically detect a type of tool attached to the tool carriers 210 and to obtain the desired tool pressure and / or state of the at least one actuator 300 from the first record 570 in dependence of the type of tool 15 attached to the tool carriers 210. Techniques for automatically detecting which type of tool that has been attached to the tool carriers 210 can be implemented using, e.g., radio frequency identification (RFID) tags embedded into the tool which are read by corresponding readers arranged on the active part 110, or by scanning identification codes on the tools, such as QR-codes with a scanner or a personal device such as a smart phone 20 that then communicates the tool type to the control unit 140, 150, 170. The control unit 140, 150, 170 optionally also comprises a second record 580 which holds data that is indicative of an applied tool pressure as function of the state of the at least one actuator 300. In other words, the second record 580 allows the control unit to at least approximately map a given tilt angle 320 or position of the adjustable mass part weight 25 along the track 600 to an applied tool pressure, and vice versa. In this case the control unit 140, 150, 170 can be configured to obtain the current tool pressure from the second record 580 as function of the current state of the at least one actuator 300. The surface processing equipment 100 optionally comprises a display device, e.g., arranged on the adjustable mass part 120 and / or on the remote control device 155. The control unit 140, 150, 170 can then 30 be configured to display the current tool pressure on the display device. The control unit 140, 150, 170 can also use the second record 580 to translate an operator input of a desired applied tool pressure into a corresponding state of the actuator, and control the actuator by generating an appropriate control signal 590. 2026200332   11 Jun 2026 An inertial measurement unit (IMU), sometimes also referred to as an electronic spirit level, can be arranged on the surface processing equipment 100, such as on the active part 110 to measure surface slope and / or an angle of the support plane of the tool carriers 210 relative to a horizontal plane. This device can output a slope signal 510 which can be used 5 by the control unit 140, 150, 170 to adapt the tilt angle 320 of the adjustable mass part 120. For instance, the control unit 140, 150, 170 can be configured to obtain data 510 indicative of a slope of the surface 101 relative to a horizontal plane, and to limit the tilt angle 320 to be within a stability range configured at least in part in dependence of the slope of the surface 101. The stability range can be a preconfigured stability range, or one that is set 10 dynamically in dependence of a measure normal load on the tool carriers 210, e.g., as a tilt angle value where the applied tool pressure goes to zero with an added stability margin of a few degrees. The control unit 140, 150, 170 will then not control the at least one actuator 300 to a tilt angle outside of the stability range. The control unit may generate an alarm signal in case the slope changes such that the current tilt angle ends up outside of the 15 stability range. The control signal may also automatically adjust the tilt angle to stay within the stability range in case the slope of the surface changes as the surface processing equipment 100 moves around on the surface 101. The first and / or the second record may also comprise data related to a slope of the surface to be processed relative to the horizontal plane. The slope of the surface can therefore be 20 accounted for when deciding on an appropriate configuration of the actuator 300 that governs the state of the adjustable mass part 120. Many types of surface processing equipment, such as floor grinders, are often connected to dust extraction devices which extract dust that is generated during processing of the surface 101. A hose can for instance be connected between the active part 110 and the 25 dust extractor, through which dust is removed during surface processing. A connection 240 for a dust extractor hose is shown in Figure 2, and an example dust extractor hose 410 is illustrated in Figure 4C. Techniques for measuring a dust extraction rate are known in the art, e.g., from WO2024084016A1 and will therefore not be discussed in more detail herein. It is also possible to monitor the air flow that carries the dust away from the surface 30 processing equipment in order to determine the dust generation rate of the surface processing equipment. This type of dust generation rate sensor can be arranged on the surface processing equipment, such as at the connection 240 for the dust extractor, or in connection to the dust extractor. Dust extraction rate can be given, e.g., in terms of the weight of generated dust per unit of time, and / or in terms of a dust particle size distribution. 2026200332   11 Jun 2026 A dust generation rate sensor can be realized using a number of different techniques known in the art. Optical particle sensors represent one of the most common approaches to realtime dust generation rate measurement. These sensors operate by projecting a laser or light emitting diode (LED) beam through the airstream. As dust particles pass through the 5 beam, they scatter light. A photodiode detects this scattering, and the amount and pattern of scattered light are used to estimate the number and size of particles. More advanced optical sensors can classify particles by size (e.g., PM2.5, PM10) and even estimate mass concentration based on statistical models. Triboelectric sensors detect the tiny electrical charges generated when dust particles collide with or pass near a grounded metal probe 10 placed in the airflow. The friction or contact between particles and the sensor surface causes a flow of electrons, which is detected and converted into a signal proportional to dust concentration. Opacity sensors work by measuring the reduction in light transmission across a beam that passes through the dust-laden airflow. A transmitter sends infrared or visible light through the duct or hose to a receiver. As dust increases in the path, the beam 15 is blocked or scattered, reducing the received signal. For environments where optical and contact-based sensors may not perform well—such as very moist, sticky, or dense dust conditions—microwave or radio frequency (RF) sensors offer an alternative. These systems transmit electromagnetic waves through the dust-filled airstream. Dust particles affect the signal’s attenuation or phase shift, and these changes are analyzed to estimate dust 20 concentration. The control unit 140, 150, 170 can be adapted to measure the dust generation rate 520 of the tools supported by the tool carriers 210, and to adjust the state of the at least one actuator 300 to reduce a difference between a current dust generation rate and a desired dust generation rate. The dust generation rate 520 can be given, e.g., in terms of the weight 25 of dust generated per unit of time and / or in terms of a dust particle distribution. Note that the dust extraction rate can be both too high and too low. A too high dust extraction rate can be undesired due to excessive tool wear or surface processing result. A too low dust extraction rate can be undesired for efficiency reasons. A given tool type may also be associated with a preferred dust particle size distribution. The control unit 140, 150, or the 30 remote server 170 can maintain a record of desired dust generation rates for different types of surface processing operations and for different types of tools. For many surface processing operations involving use of abrasive tools, the dust generation rate often increases with applied tool pressure. The control unit can therefore be configured to increase the applied tool pressure if the current dust generation rate is below a desired 2026200332   11 Jun 2026 dust generation rate, and decrease the applied tool pressure if the current dust generation rate is above the desired dust generation rate. The surface processing equipment 100 may also comprise an arrangement for measuring the applied tool pressure in a more direct manner. Such an arrangement may comprise 5 pressure sensors such as, e.g., load cells and / or strain gauges arranged in connection to the tool carriers 210 and / or in connection to the support arrangement 130. The pressure sensors provide output signals 530 that are indicative of the applied tool pressure. In this case the control unit 140, 150, 170 can be adapted to measure the load 530 on the tools supported by the tool carriers 210, and to automatically adjust the state of the at least one 10 actuator 300 to reduce a difference between a current load on the tools and a desired load on the tools. The desired load on the tools may, e.g., be configured in dependence of the current surface processing operation that is to be performed and / or in dependence of the type of tools that have been mounted on the tool carriers 210, such as the grit of abrasive floor grinding tools. As mentioned above, for a floor grinder such as the floor grinder in 15 Figure 1, tool load increases if the adjustable mass part 120 is rotated in the forward direction F and decreases if the adjustable mass part 120 is rotated in the reverse direction. According to an example use case, an operator can configure a desired applied tool pressure in terms of N / m2 using, e.g., the remote control device 155. The control unit then accesses the second record 580 in order to find the corresponding actuator state. The 20 actuator is then controlled towards the desired state, whereby the desired applied tool pressure is configured. The operator can, for instance, obtain the desired applied tool pressure from the manufacturer of the tools in use, or from some other information source. According to some aspects, the control unit 140, 150, 170 is adapted to monitor tool wear of the tools configured to rotatably engage the surface 101 at the applied tool pressure, and 25 to adjust the state of the at least one actuator 300 to reduce a difference between a current tool wear and a desired tool wear. Tool wear can be measured by a reduction in height of the tool carrier plane above the surface. This height can be measured to a probe which extends from the chassis of the surface processing equipment to the surface, or by a sensor such as a radar, stereo camera, or lidar sensor arranged looking down at the surface. It is 30 also possible to embed sensors into the actual tools in order to measure tool wear. WO2022240330 A1 describes several different techniques for measuring tool wear in real time. The control unit, having regard to the desired tool wear rate, can increase the applied tool pressure by adjusting the position of the adjustable mass part correspondingly in case 2026200332   11 Jun 2026 the current tool wear is too low, and decrease the applied tool pressure by adjusting the position of the adjustable mass part correspondingly in case the current tool wear rate is too high. According to some other aspects, the control unit 140, 150, 170 is adapted to monitor a 5 temperature associated with the tools configured to rotatably engage the surface 101 at the applied tool pressure, and to adjust the state of the at least one actuator 300 to reduce a difference between a current tool temperature and a desired tool temperature. Temperature can be measured by a temperature sensor mounted in connection or at least in vicinity of the tools, or by an infrared detector arranged to observe the tools. The applied tool pressure 10 can be reduced by the control unit in case the temperature becomes too high, i.e., above the configured maximum or desired tool temperature, and increased if the temperature is below the desired tool operating temperature. The control unit 140, 150, 170 can also be adapted to monitor one or more characteristics of an electrical winding current 540 associated with one or more drive motors 180, 185 of 15 the equipment 100, and to adjust the state of the at least one actuator 300 to reduce a difference between current winding current characteristics and desired winding current characteristics. The monitoring of winding current can, for instance, be implemented using a function 560 based on machine learning (ML) techniques or artificial intelligence (AI). The one or more characteristics of the electrical winding current 540 can also comprise a 20 power consumption 545 of drive current magnitude of an electric motor used to drive the tool carriers. The control unit can automatically adjust the applied tool pressure in order to obtain a pre-set drive current or power. According to other aspects, the control unit 140, 150, 170 is adapted to record a sound 550 generated by the surface processing equipment 100 during processing of the surface 101, 25 and to adjust the state of the at least one actuator 300 to reduce a difference between the current sound and a desired sound generated by the surface processing equipment 100. Using AI (in particularly a neural network) to adjust applied tool pressure by the at least one actuator 300 based on one or more of the external input signals 510, 520, 530, 540, 550 indicated in Figure 5 has been found to give good results in many types of surface 30 processing operations such as floor grinding and polishing operations. Particularly inferred back-EMF 540 from drive motor winding currents has been found to give good results when used together with AI-based control algorithms. An AI-based control architecture 500 is 2026200332   11 Jun 2026 essentially a feedback control system that adjusts tool pressure in real-time, based on one or more of the input signals 510, 520, 530, 540, 550 indicated in Figure 5. The function 560 is designed to first learn the relationship between input signals such as motor signals (especially back-EMF) and optimal applied tool pressure, then to dynamically adjust tool 5 pressure in dependence of the one or more input signals. Possible machine learning structures to use in the function 560 comprise feedforward neural networks (FNN), recurrent neural networks (RNN), and convolutional neural networks (CNN). The machine learning structure implemented by the function 560 is preferably trained using 10 labelled data, which can be obtained from practical experimentation of different applied tool pressures used in different operating scenarios and with different types of tools, used in different surface processing operations. It is, for instance, possible to use the camera systems described in WO2023096544 A1 in order to inspect the result of a given adjustable mass part actuator setting during the training phase. Dust generation rate can also be used 15 as metric of efficiency, as discussed above, where preferred dust generation rates are often known beforehand. Labelled training data can also be obtained at least in part from computer simulation of different surface processing machines used to process different types of surfaces using different types of tools. The machine learning structure is trained until an implementation of the function 560 is found to give acceptable results in practical 20 experimentation, i.e., actual processing of various surfaces 101. The control unit 140,150 can also be adapted to control a rotation speed of the one or more tool carriers 210 about one or more axes of rotation 220, 230 in combination with control of the state of the at least one actuator 300. The control unit 140, 150, 170 can be adapted to vary the applied tool pressure in combination with the rotation speed of the one or more tool 25 carriers and monitor one or more of the signals 510, 520, 530, 540, 550. The control unit 140, 150, 170 can then select a combination of applied tool pressure and speed of rotation which provides the desired result. The control unit 140, 150, 170 can furthermore be adapted to control a speed of one or more traction wheels 130 of the surface processing equipment 100 in combination with control of the at least one actuator 300. 30 Figure 10 is a flow chart illustrating methods which summarize at least some of the discussions above. There is illustrated a computer implemented method performed in a control unit 140, 150, 170 adapted to control an operation of surface processing equipment 100 for processing a surface 101. The equipment 100 comprises an active part 110, an 2026200332   11 Jun 2026 adjustable mass part 120, at least one actuator 300, a support arrangement 130, and a control unit 140, 150, 170. The active part 110 comprises one or more tool carriers 210 arranged to support respective tools configured to rotatably engage the surface 101 at an applied tool pressure. The support arrangement 130 is connected to the active part 110 and 5 adapted to support the floor grinder 100 on the surface 101. At least one actuator 300 is adapted to control a position of the adjustable mass part 120 relative to the active part 110 and relative to the support arrangement 130 in response to a control signal, thereby controlling a position of a mass center 125 of the adjustable mass part 120 in relation to a mass center 115 of the support arrangement 130 and in relation to a mass center 115 of 10 the active part 110. The method comprises obtaining S1 data 510, 520, 530, 540, 545, 550 indicative of a difference between a current tool pressure and a desired tool pressure, and controlling S2 a state of the at least one actuator 300 to reduce the difference between current tool pressure and desired tool pressure. It is appreciated that all technical features and functions of the surface processing 15 equipment 100 discussed herein represent optional features of the disclosed method. Figure 11 schematically illustrates, in terms of a number of functional units, the components of a control unit such as the floor grinder control unit 140 or a control unit comprised in the remote control device 150. The control unit may implement one or more of the above discussed functions of the floor grinder 100. The control unit is configured to execute at 20 least some of the functions discussed above for control of a floor grinder 100. Processing circuitry 1110 is provided using any combination of one or more of a suitable central processing unit CPU, multiprocessor, microcontroller, digital signal processor DSP, etc., capable of executing software instructions stored in a computer program product, e.g., in the form of a storage medium 1120. The processing circuitry 1110 may further be provided 25 as at least one application specific integrated circuit ASIC, or field programmable gate array FPGA. Particularly, the processing circuitry 1110 is configured to cause the control unit 101 to perform a set of operations, or steps, such as the methods discussed in connection to Figure 10. For example, the storage medium 1120 may store the set of operations, and the 30 processing circuitry 1110 may be configured to retrieve the set of operations from the storage medium 1120 to cause the control unit 800 to perform the set of operations. The set of operations may be provided as a set of executable instructions. Thus, the processing circuitry 1110 is thereby arranged to execute methods as herein disclosed. 2026200332   11 Jun 2026 The storage medium 1120 may also comprise persistent storage, which, for example, can be any single one or combination of magnetic memory, optical memory, solid state memory or even remotely mounted memory. The control unit 800 may further comprise an interface 1130 for communications with at 5 least one external device. As such the interface 1130 may comprise one or more transmitters and receivers, comprising analogue and digital components and a suitable number of ports for wireline or wireless communication. The processing circuitry 1110 controls the general operation of the control unit 800, e.g., by sending data and control signals to the interface 1130 and the storage medium 1120, by 10 receiving data and reports from the interface 1130, and by retrieving data and instructions from the storage medium 1120. Other components, as well as the related functionality, of the control node are omitted in order not to obscure the concepts presented herein. There is also disclosed herein a computer readable medium carrying a computer program comprising program code means for performing the methods illustrated in Figure 10 and 15 the functions discussed above, when said program product is run on a computer. The computer readable medium and the code means may together form a computer program product.

Claims

1. Surface processing equipment for processing a surface, the equipmentcomprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit,5        the active part comprising one or more tool carriers arranged to supportrespective tools configured to rotatably engage the surface at an applied tool pressure,where the support arrangement is connected to the active part and adapted to support the surface processing equipment on the surface,10        where the at least one actuator is adapted to control a position of theadjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to the support arrangement and in relation to a mass center of the active part,15        where the surface processing equipment is adapted to be automaticallytipped over about a contact area between the surface and the support arrangement, in response to control of the position of the mass center of the adjustable mass part by the at least one actuator towards a rear of the surface processing equipment.20 2.    The surface processing equipment according to claim 1, where the surfaceprocessing equipment is arranged to be controlled from a distance by a remote control device which is arranged to communicate wirelessly or over a wired communication channel with a control unit onboard the surface processing equipment.25 3.    The surface processing equipment according to claim 2, where the surfaceprocessing equipment is arranged to be guided solely from a distance.

4. The surface processing equipment according to any one of the previousclaims, where the one or more tool carriers are accessible when the surface processing equipment is tipped over in a tipped over position.2026200332   11 Jun 20265.    The surface processing equipment according to any one of the previousclaims, wherein a zero applied tool pressure is obtained as the surface processing equipment is tipped over about the contact area.

6. The surface processing equipment according to any previous claim, the5 surface processing machine is devoid of a handle portion for guidance of the surface processing equipment on the surface.

7. The surface processing equipment according to any one of the previousclaims, where the adjustable mass part is pivotably connected to the active part, where the at least one actuator comprises a linear actuator and / or a rotary10 actuator arranged to control a tilt angle of the adjustable mass part in dependence of the control signal from the control unit.

8. The surface processing equipment according to claim 7, where the controlunit is configured to obtain data indicative of a slope of the surface relative to a horizontal plane, and to control the tilt angle in relation to a stability range15 configured at least in part in dependence of the slope of the surface when the surface processing equipment is to be tipped over.

9. The surface processing equipment according to any one of the previousclaims, where the control unit is adapted to measure a load on the tools supported by the tool carriers, and to adjust the state of the at least one actuator to reduce a 20 difference between a current load on the tools and a desired load on the tools.

10. The surface processing equipment according to any one of the previous claims, where the adjustable mass part comprises at least a first adjustable mass part and a second adjustable mass part arranged to rotate about respective pivot axes, where respective actuators are connected between the active part and the 25 adjustable mass parts and adapted to control a tilt angle of the adjustable mass part about its pivot axis.

11. The surface processing equipment according to claim 10, where the first adjustable mass part and the second adjustable mass part are separated by a plane extending traversal to the pivot axes.2026200332   11 Jun 202612. The surface processing equipment according to any one of the previous claims, comprising at least one tool carrier adjustment actuator adapted to control a pose of the active part relative to the surface in response to a pose control signal.5 13. The surface processing equipment according to any one of the previousclaims, where the equipment is a floor grinder, a power trowel, a floor polishing machine, or a floor cleaning machine.

14. A computer implemented method performed in a control unit adapted to control an operation of surface processing equipment for processing a surface, the10 equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit, the active part comprising one or more tool carriers arranged to support respective tools configured to rotatably engage the surface at an applied tool pressure, where the support arrangement is connected to the active part and adapted to support the surface processing15 equipment on the surface, where the at least one actuator is adapted to control a position of the adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to a mass center of the support arrangement and in relation to a mass center of the active part, the20 method comprisingautomatically tipping the surface processing equipment over about a contact area between the surface and the support arrangement by means of controlling the position of the mass center of the adjustable mass part by the at least one actuator towards a rear of the surface processing equipment.25 15. The computer implemented method according to claim 14, the methodcomprisingobtaining data indicative of a difference between a current tool pressure and a desired tool pressure, andcontrolling a state of the at least one actuator to reduce current tool30 pressure to zero tool pressure.2026200332   11 Jun 202616. The computer implemented method according to claim 14 or 15, comprising controlling the surface processing equipment solely from a distance by a remote control device which is arranged to communicate wirelessly or over a wired communication channel with a control unit onboard the surface processing5 equipment.

17. The computer implemented method according to any one of claims 14-16, wherein the surface processing equipment is devoid of a handle portion for manual guidance of the surface processing equipment on the surface.

18. A computer program comprising program code means for performing the10 method of any one of claims 14-17 when said program is run on a computer or on processing circuitry of a control unit.

19. A computer readable medium carrying a computer program comprising program code means for performing the method of any one of claims 14-17 when said program product is run on a computer or on processing circuitry of a control 15 unit.

20. Surface processing equipment for processing a surface, the equipment comprising an active part, an adjustable mass part, at least one actuator, a support arrangement, and a control unit,the active part comprising one or more tool carriers arranged to support20 respective tools configured to rotatably engage the surface at an applied tool pressure,where the support arrangement is connected to the active part and adapted to support the floor grinder on the surface,where the at least one actuator is adapted to control a position of the25 adjustable mass part relative to the active part and relative to the support arrangement in response to a control signal, thereby controlling a position of a mass center of the adjustable mass part in relation to a mass center of the support arrangement and in relation to a mass center of the active part,where the surface processing equipment is adapted for rotation about a30 contact area between the surface and the support arrangement to a tipped over2026200332   11 Jun 2026position for providing access to the one or more tool carriers, and to be automatically biased toward the tipped over position in response to control of the position of the mass center of the adjustable mass part by the at least one actuator towards a rear of the surface processing equipment.

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