FI20186071A1

FI20186071A1 - A user interface and a method to operate a user interface

Info

Publication number: FI20186071A1
Application number: FI20186071A
Authority: FI
Inventors: Jussi Kapanen
Original assignee: Kemppi Oy
Priority date: 2018-12-12
Filing date: 2018-12-12
Publication date: 2020-06-13
Also published as: WO2020120831A1

Abstract

The present invention relates to a sliding control for adjusting a value of a parameter via a computer-implemented user interface (1, 2). The user interface comprises a display apparatus and an input apparatus. Input is received from the user with the input apparatus. The input comprises a single, moveable focal point (3, 3’) in an input area defined by the display apparatus. The sliding control comprises a first line (9a) indicating a radial direction from a fixed center along a plane defined by the display apparatus for visualizing an operative connection between the control element (5) and the focal point (3, 3’). Movement of the focal point (3, 3’) is configured to be projected to a movement of the control element (5) of the sliding control on basis of a directional angle (a) defined between a reference line (90) in the plane traveling through the fixed center (10) and the direction of the first line (9a) defined by the focal point (3, 3’). The value of the parameter is adjusted on basis of the movement of the control element (5).

Description

A user interface and a method to operate a user interface Field The present invention relates to user interfaces, for example touch, gesture and eye-gaze input enabled user interfaces, UI.

More particularly, the present invention relates to a sliding control in a user interface as well as to a method and a computer program product related to operating a sliding control user interface.

Background In some applications, it would be beneficial if a sliding control input provided to a user in a user interface for adjusting an input value would enable both fast adjustment of large value changes and precise fine adjustment of values.

Examples of such applications from the technology area of the applicant are for example welding, carbon arc gouging and plasma cutting.

However, other applications exist which may benefit from such solution.

A non-limiting list of examples is for example audio and video browsing or scrubbing, audio, video and image editing, such as color and tone adjustments to mention a few.

Laws of physics and limitations of human motor functions seem to disable such devices simply because precise adjustment tends to make the sliding control longer, whereas quick adjustment requires a short sliding control device. = 20 Existing solutions for precise adjustment, such as rotating knobs, work enable N precise fine adjustment, and allow also a large adjustment scale for input values.

W However, this comes with cost of reduced speed: large value changes cannot be - made fast. = = A sliding control input is a good solution, as long as the trajectory of the slider 3 25 fits reasonably with a natural trajectory of for example a hand that is used for 2 operating the sliding control.

However, due to size limitations, a sliding control may be unprecise if a very precise value is needed to be input from a wide range of values.

On a touch or gesture UI, precision of the sliding control can beimproved by making the sliding control longer. However, the available area on the UI limits such lengthening. If there are plenty of values between the minimum and the maximum value, precise fine adjustment may become even impossible. On touch and gesture Uls, yet another problem arises: accuracy of the movement of the hand, finger or other pointer used for adjusting the sliding control. This problem has been in focus of solutions developed for example for user interfaces used by a driver of a vehicle: the UI allows the pointer to use even outside the sliding control and uses for example projection of the movement of the pointer to operate the slider. A solution is needed, that solves all the above problems, and further, is intuitive even for a first-time user. Description of the related art Patent application publication US20070146341 A1 discloses an idea of an interaction technigue in which a gesture is used to operate an operating element of a linear slider using touch screen. Patent US9513744 discloses a virtually displayed slider that may be operated by moving a finger on a screen or pad. Instead of being required to virtually grab a handle or a knob of the slider, the user may touch the slider at any point and operate the slider simply by moving his/her finger left or right. This solution © 20 removes the need to touch exactly the current location of the handle or knob.

O a An article published in the internet https://www.howtogeek.com/254608/how- N to-scrub-through-audio-and-video-slowly-in-ios/ dated May 13%, 2016 discloses E a hidden method in Apple iPhone video player's touch user interface for < “scrubbing”, in other words fast-forwarding or reversing through an audio or 3 25 video to a particular location with a slider. By moving a finger vertically with o respect to the horizontal, linear slider, the speed of scrubbing action can be adjusted. However, this feature is not intuitive, and few people have noticed it, which becomes apparent from the mere need of such articles disclosing andexplaining the functionality of this ‘hidden’ feature.

Further, speed of scrubbing action in this solution can be selected only in coarse steps.

Speed of scrubbing is also somewhat difficult to predict and requires trial and error to learn.

Further, the disclosed solution changes the speed/accuracy of the adjustment in steps, although the phenomenon to be adjusted is continuous in nature.

Summary In this document, we use term user interface, which is equivalent to term graphical user interface also appearing in the related literature.

An object is to provide a method and apparatus so as to solve the problem of a sliding control that enables both quick, coarse adjustment and precise fine grain adjustment, and which is also intuitive for the user.

The objects of the present invention are achieved with a computer-implemented sliding control according to the characterizing portion of claim 1. The objects of the present invention are further achieved with an apparatus according to the characterizing portion of — claim 11. The preferred embodiments of the invention are disclosed in the dependent claims.

According to a first aspect of the invention a sliding control is provided for adjusting a value of a parameter via a computer-implemented user interface.

The © 20 user interface comprises a display apparatus configured to visually display a N control element of the sliding control, and an input apparatus configured to = receive input from a user.

The input from the user preferably comprises a single, - moveable focal point in an input area defined by the display apparatus. = - The sliding control comprises a first line indicating a radial direction from a fixed 3 25 center along a plane defined by the display apparatus for visualizing an operative o connection between the control element and the focal point.

Movement of the focal point is configured to be projected to a movement of the control element of the sliding control on basis of a directional angle defined between a reference linein the plane traveling through the fixed center and the direction of the radial line defined by the focal point. Value of the parameter is adjusted on basis of the movement of the control element.

According to a second aspect, moving the focal point towards the fixed center is configured to increase speed of adjustment of the value and moving the focal point away from the fixed center is configured to increase accuracy of the adjustment of the value of the parameter.

According to a third aspect, the sliding control is activated when a predefined activation area is pointed by the user. The first line may appear in the user interface after activating the sliding control. According to a fourth aspect, the user interface provides visual or audible indicators indicating the value or a change of the value of the parameter. According to a fifth aspect, the visual indicators comprise at least one of a numerical value of the parameter and a visual indicator of direction of the first line shown in the control element. According to a sixth aspect, the audible indicator comprises an audible sound and at least one of the pitch, timbre, volume, tempo and direction of the audible sound co is adjusted on basis of change of the value of the parameter. g N 20 According to a seventh aspect, the user interface comprises a curved slider track N along which the control element moves. = a According to an eighth aspect, the visual indicator further comprises visual S change of the curved slider track.

O

D S According to a ninth aspect, the user interface comprises any one of a touch user interface, an augmented reality user interface and a virtual reality user interface.

According to a tenth aspect, the sliding control is operable for adjusting value of a parameter related to any one of welding, carbon arc gouging and plasma cutting.

5 According to a first method aspect, a method for adjusting a value of a parameter with computer-implemented sliding control disposed on a user interface is provided. The method comprises visually displaying a control element of the sliding control on a display and receiving input from a user. The input from the user preferably comprises a single, moveable focal point in an input area defined by the display apparatus. A radial direction is indicated from a fixed center along a plane with a first line for visualizing an operative connection between the control element and the focal point. Movement of the focal point is projected to a movement of the control element of the sliding control on basis of a directional angle defined between a reference line in the plane traveling through the fixed center and the direction of the radial line defined by the focal point. The value of the parameter is adjusted on basis of the movement of the control element. According to a second method aspect, moving the focal point towards the fixed center is configured to increase speed of adjustment of the value and moving the oo 20 focal point away from the fixed center is configured to increase accuracy of the S adjustment of the value of the parameter.

N & According to a third method aspect, the method further comprises activating the I sliding control by pointing a predefined activation area and displaying the first = line on the display only after activating the sliding control.

~ 3 25 According to a fourth method aspect, the method further comprises providing in N the user interface visual indicators indicating the value or a change of the value of the parameter.

According to a fifth method aspect, the visual indicators comprise at least one of a numerical value of the parameter and a visual indicator of direction of the first line shown in the control element.

According to a sixth method aspect, an audible indicator is provided that indicates the value or a change in the value of the parameter. The audible indicator comprises an audible sound and at least one of the pitch, timbre, volume, tempo and direction of the audible sound is adjusted on basis of change of the value of the parameter.

According to a seventh method aspect, the user interface comprises a curved slider track along which the control element moves, and wherein the visual indicator further comprises visual change of the curved slider track.

According to an eighth method aspect, the method is operable for adjusting a value of a parameter related to any one of welding, carbon arc gouging and — plasma cutting.

According to another aspect, a computer program product is provided having instructions which when executed by a computing device or system cause the computing device or system to perform the method according to the above method aspects. ® N 20 According to a yet another aspect, a computer program product embodied on a = non-transitory computer readable medium is provided, comprising instructions = stored thereon to cause one or more processors to perform the method according E to the above method aspects. 5 K | © According to another aspect, an apparatus is provided that comprises a computer > 25 program product according to the above aspects to perform the method according to the above method aspects.

The present invention is based on the idea of projecting movement of a focal point to a curved sliding control so that the sliding control can be adjusted using the entire available input area of the user interface using either a precise, large trajectory or a quick small trajectory. A single, continuous movement of a pointer defining the focal point can intuitively switch between a more accurate and a quicker adjustment of values. Adjustment of the coarseness of adjustment is continuous in nature; in other words, there are no detectable steps, but both speed and accuracy of the adjustment depend linearly on the distance of the focal point from a fixed center point. Thus, any level of preciseness and speed is enabled between the minimum and maximum. The present invention has the advantage that it provides a very versatile user interface that is also highly intuitive to a user and can be used also with less accurate pointers. Brief description of the drawings In the following the invention will be described in greater detail, in connection with preferred embodiments, with reference to the attached drawings, in which Figure 1 shows an exemplary embodiment of a sliding control Figure 2 illustrates aspects of the exemplary embodiment Figure 3 illustrates main elements of the sliding control = 20 Figure 4a illustrates an embodiment of the sliding control with a circular

N e slider track N Figures 4b and 4c illustrate further examples of curved slider tracks, which E are not circular =~ Figure 5 illustrates a situation when a user first touches the slider in a

O ® 25 starting position

O N Figure 6 illustrates a situation in end position

Figures 7-9 illustrate fine adjustment of the parameter value using the sliding control Figure 10 illustrates and embodiment of the invention with an augmented reality UI or a virtual UI Figure 11 illustrates various methods for presenting current setting of the parameter value Figure 12 illustrates a sliding control before is it activated according to a first embodiment Figure 13 illustrates the first embodiment of figure 12 after activation Figure 14 illustrates the first embodiment when the user operates the slider Figure 15 illustrates a second embodiment a situation when the sliding control is not activated Figure 16 illustrates the second embodiment when the user has activated the sliding control Figure 17 illustrates adjustment of values with the slider according to the second embodiment Figure 18 illustrates a third embodiment in a situation when the sliding control is not activated Figure 19 illustrates the third embodiment when the user has activated the

[20] S 20 sliding control N Figure 20 illustrates adjustment of values with the slider according to the S third embodiment

I = . sai Detailed description ~ 2 The term computer refers to any electronic device comprising a processor, such 00 o 25 as a general-purpose central processing unit (CPU), a specific purpose processor

N or a microcontroller. A computer is capable of receiving data (an input) of performing a seguence of predetermined operation thereupon, and of producingthereby a result in the form of information signals (an output). Depending on context, the term computer will mean either a processor in particular or can refer more generally to a processor in association with an assemblage of interrelated elements contained within a single case or housing.

As used herein, a computer-readable medium or storage medium can be any means that can contain, store, communicate, propagate or transport a program for use by or in connection with an instruction execution system, apparatus or device. The computer readable medium can be, for example but not limited to, an electronic, magnetic, optical electromagnetic, infrared or semiconductor system, apparatus, device or propagation medium. A non-exhaustive list of more specific examples of the computer-readable medium can include the following: an electrical connection having one or more wires, a portable computer diskette, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, and a portable compact disc read-only memory (CDROM).

The figure 1 shows an exemplary embodiment of a sliding control according to the invention using a touch UI. The touch UI comprises a touch area (1) and a display area (2), which are preferably but not necessarily collocated. The user may use his finger (8) for pointing any location on the UI. In the display (2) a curved slider track (6) is shown that represents a track of the sliding control. A © slider (5) is shown on the track (6). Adjustment values may be shown in various 2 ways. For example, a numerical value (7b) may be shown in a dedicated portion N of the display area (2) and/or the visual appearance of the sliding control may be = adjusted according to the position of the slider (5). In this embodiment, the slider E 25 (5) represents a control element. The position of the control element is defined = and used to define a value of a parameter. For example, color or brightness (7a) 3 of the slider track (6) may change based on the position of the slider (5). Further, S adjustment may be indicated with any other visual and/or audible manner. For example, pitch, timbre, volume, tempo or the perceived direction of an audible sound played to the user may be changed in dependence of the adjustment value.

Any indications of adjustment of the value, whether visual or audible, may be used alone or in any combination.

Further, style and combination of the indications may be selectable by the user.

The slider (5) is preferably associated with an invisible activation area (4), which includes area occupied by the slider (5) and which further extends to the vicinity of the slider (5). This activation area (4) enables activating the sliding control with a relatively inaccurate pointing device.

In this example, user’s finger (8) is used as the pointing device.

In other embodiments, gaze or a mechanical or technical pointing device such as a stylus, mouse, joystick, touchpad or alike may be used for pointing a location in the UI.

The point that the user points at may be referred to as a focus or as a focal point.

Figure 2 illustrates further aspects of the exemplary embodiment.

When the user activates the sliding control by placing the focus, in other words pointing the slider or the activation area, at least one further visualization element may appear in the display area (2). The at least one visualization element may comprise at least one of a radial line (9a) extending radially from a fixed center and a graphical visualization (9b) in the slider.

The radial line (9a) visualizes a direction from the center that is defined by position of the slider, and the graphical visualization (9b) indicates the same radial direction from the center.

The radial line (9a) as shown in the display may start from the center, but this is not necessary: it is sufficient = that the radial line (9a) indicates the direction from the fixed center.

The fixed N center from which the visualization element extends may but does not need to W be shown in the display area.

In the figure 2, the focus (3) is not on the slider, = but on the radial line (9a) further away from the center than the slider track (6), _ 25 on the opposite side of the slider track (6) compared to the center. ~ 3 Figure 3 illustrates main elements of the sliding control that affect to the N adjustment of a parameter value with the sliding control.

The center (10) may be invisible or visible. Adjustment of the parameter value is based on a directional angle ao defined between a reference line (90) and the radial line (9a). As can be seen in the figure 3, a short trajectory (11) of a motion or in the vicinity of the center (10) near the slider track (6) is much shorter than a long trajectory (12) further away from the center (10). Using the short trajectory (11), a user can apply quick coarse adjustment of a value with the sliding control. Using the long trajectory (12), the user can apply precise fine adjustment of a value with the sliding control. Change of the parameter value adjusted with the sliding control is based on the directional angle a that is defined in relation to the reference line (90). When the radius is long, a small change of the directional angle a and thus a small change of the parameter value requires a relatively long movement along a long trajectory (12), whereas, when the radius is short, a shorter movement along a short trajectory (11) causes bigger change in the directional angle a and thus a bigger change in the parameter value. Directional angle a is preferably defined in relation to the reference line (90) that extends from the center (10). This reference line (90) is preferably not shown to the user, since it may unnecessarily complicate the user interface. However, displaying the reference line (90) may be selected for some embodiments and/or by some users.

When the sliding control is in use, the direction defined by the directional angle a © is preferably visualized to the user. The simplest method to visualize the direction R defined directional angle a is to display a visible radius extending from the center N (10). Even if the reference line (90) is not shown, the user can easily detect = change of the direction during adjusting. The direction may also be visualized z 25 with the slider (5); when the slider track 6 is shown, position of the slider (5) S visualizes the direction. Further, the graphical design of the slider (5) may = visualize the direction. For example, the slider (5) may comprise arrow(s), stripes S or lines, which are parallel to the radial line and thus indicates the direction. This helps the user to easily recognize the current direction.

Figure 4 illustrates an embodiment, where a numerical value (7b) is shown on top of the center of a slider track (6) that has a form of a sector of a circular annulus, in other words a circular ring sector. The location of a numerical visualization is not limited to any particular location on the UI. The location may also change depending on whether the sliding control is actively used or not. Change of the location of the numerical visualization improves user's ability to recognize when the sliding control is under active control of the user. However, the area on the touch area of the UI occupied with the numeric value may be used for operating the sliding control egually to any other area on the touch area. Figures 4b and 4c illustrate further examples of curved slider tracks (6), which are not circular but rather an angular sector of an elliptical annulus or other curved form. This is to illustrate that the slider may have a form of a sector of any kind of circular, elliptical or curved annulus. Figure 5 illustrates a situation when a user first touches the slider (5), for example — the slider illustrated in the figure 4, with his finger (8). Activation of the sliding control may be visualized for example by changing the location at which the associated numerical value (7b) is shown. Such change of location of the numerical value (7b) occurs for example between the situations in the figures 4a and 5. Conveniently, in addition to indicating activation of the sliding control, activation moves the numerical value (7b) to a position that is not covered by the © pointing device, such as the hand or finger (8) of the user. Thus, the numerical 2 value (7b) remains better visible to the user during adjustment of the sliding N control.

N = Figures 5 and 6 illustrate a gesture used for quick, coarse adjustment of a value _ 25 using the sliding control. Figure 5 shows an initial position, and figure 6 shows S the end position. The user simply moves the focus (3) from the original position = (3) of the slider to a new location (3). Thereby, the numerical value (7b) in this - example guickly changes from 17.6 to 8.2. Trajectory of this move may follow the slider track (6), but it does not have to: any track (13) between the originalposition of the focus (3) to a new location is interpreted as moving the slider to the new location as defined by the directional angle.

Especially, the user can use a direct line as a shortcut between two positions, which maximizes speed of the change with minimum effort along as short trajectory as possible.

The movement of the focus is projected into a movement of the slider (5) that acts as the controlelement and defines the directional angle.

Figures 7 to 9 illustrate fine adjustment of the parameter value using the sliding control.

Visualization of the radial line (9a) intuitively attracts the user to try moving his finger (8), and thus the focus, further away from the center and the track (6) of the sliding control.

The finger (8) represents a pointing device in this embodiment that defines the focus.

Moving the finger only along the radial line (9a) does not adjust the parameter value.

However, the trajectory of the focus may simultaneously have both radial motion components and tangential motion components that change the directional angle of the radial line (9a). Thus, the user may simultaneously adjust both the coarseness of the adjustment and the parameter value.

This is illustrated with the arrow 14 illustrating a trajectory of the finger (8). The parameter value is adjusted from 8.2 in the figure 7 to 10.1 in the figure 8. After moving his finger (8) further away from the fixed center, the user is enabled to perform much more precise adjustment of the value by moving the focus defined by his finger (8) about the center as shown with the arrow (15) in the figure 8, since the trajectory of the movement needed to make a change = in the directional angle and thus in the parameter value is clearly longer than N anywhere near the center, for example on the slider track (6). The user is now "N enabled to perform a very accurate small change in the value, in this case > 25 adjusting the numerical value from the value 10.1 in the figure 8 to value 10.2 in E the figure 9. When moving his finger along trajectories 14 and 15, the movement S is projected to the motion of the slider (5), and thus the slider (5) moves along = the slider track (6) accordingly even when the user does not actually point the

N slider (5) itself.

Figure 10 illustrates and embodiment of the invention with an augmented reality UI or a virtual UI, in which gestures are used for input. A virtual display may be provided to the user using any known virtual display or augmented reality devices. In this example, the user wears virtual or augmented reality display glasses, which enable reflecting displayed items in sight of the user so that the items appear to show in an area that does not have any physical display device. The sliding control may be shown to the user in the virtual display area (2), and movement of the hand or the finger of the user may be detected using any known method for gesture input and interpreted as an input for indicating the focus that is used for operating the sliding control.

In another embodiment, not shown, the sliding control is displayed on a traditional computer screen, and the user may use any type of traditional pointing devices, for example a mouse or a touchpad, to define the focus that adjusts the sliding control.

Figure 11 illustrates various methods for presenting current setting of the parameter value adjusted with the sliding control to the user. Any of these methods may be used either alone or in parallel. Visual indicators may comprise any one or any combination of a numerical value (7b), visual change of the slider track (7a) and a separate indicator area (7c). Visual indicators (7a, 7c) may comprise change of color, brightness, shape or size. In addition to visualization, © any other sensory capabilities of the user may be utilized for indicating change of 2 parameter values, including haptic and auditory feedback. Haptic indicators may N be, for example vibrotactile. Also, newer types of feedback recently disclosed in = the literature may be applied in parallel to visual feedback. These include but are E 25 not limited to thermal feedback or feedback utilizing any of the sensory = capabilities of a human user. Also sonification may be applicable. An audible 3 sound may be presented to the user either continuously or only during S adjustment of the sliding control. A change in the sound may be used to indicate adjustment. For example, pitch, timbre, volume, tempo or direction of a sound may be adjusted based on the position of the sliding control. Other than visualfeedback may be particularly beneficial when the use case is such that the user needs to focus his/her gaze entirely on the task at hand and looking at any visual indicators of the parameter value would disturb the task. Multimodal feedback may be provided using any combination of feedback methods may be used.

Figure 12 illustrates a sliding control before is it activated according to a first embodiment. A visual indicator (7a) of the current position of the slider track (6) is shown, as well as the slider (5). Graphical representation of the slider may comprise elements that further visualize the directional angle, such as the lines in the slider (5) shown in this figure that are parallel to the currently invisible radial line. The activation area (4) illustrated with a dotted line is not visible to the user. The activation area (4) preferably covers at least the slider (5) and preferably also some predefined area outside the slider itself. The activation area (4) may be in the vicinity of the slider (5), as in this example, but it may also be more distant for example when activation is based on a gesture. When we refer to an area in the vicinity of the control element, the area occupied by the control element itself is included in this area.

Figure 13 illustrates the first embodiment of figure 12 after activation. The slider (5) follows the focal pointed by the finger (8) of the user. Figure 14 illustrates the first embodiment when the user operates the slider.

When the user moves his finger (8) in the touch area (2), the focus (3) on the = display area (2) moves. The trajectory of the motion of the focus (3) is projected N to movement of the slider (5), so that the slider (5) moves along the slider track W (6). The length of the curved slider track (6) indicates limits of the available or = allowed control values. The slider track (6) is typically shown as a bar or as a line * 25 having a non-zero width. Although figure 14 shows several types of indicators S (7a, 7b, 7c), the amount and type of indicators (7a, 7b, 7c) used for indicating = the value set with the sliding control is selectable.

A radial line (9a) visually indicates the mutual coupling between the focus (3) and the slider (5). The radial line (9a) may appear whenever the sliding control isactivated, or it may appear only when the focus (3) is moved away from the slider (5) and/or the area occupied by the slider track (6). Figures 15-17 illustrate a second embodiment. In this embodiment, the slider track is not shown in the display. However, the control operations performed by the user are similar and have similar effects to the sliding control and to the parameter values as in the first embodiment. Figure 15 illustrates a situation when the sliding control is not activated. The slider (5) is visually coupled to the center (10) with a section of the radial line (9a) between the center (10) and the slider (5), which is, in this embodiment, always shown. An activation area (4) is defined in vicinity of the slider (5) which is not visible to the user. This enables the user to activate the sliding control even with a less accurate pointer, such as a hand or a finger. Graphical appearance of the slider (5) may include further indicators of the current radial angle. In this example, short stripes are shown in the slider (5) that are parallel to the radial — line (9a). Figure 16 illustrates the second embodiment when the user has activated the sliding control by activating it by touching the activation area (4) with his finger (8). As explained above, any other pointer may be used to indicate the focus (3) depending on the type of UI on which the sliding control is disposed. The radial line (9a) starting from the center (10) is extended so that is visible on both sides = of the slider (5). The radial line (9a) may extend over the entire display area (2).

N N Figure 17 illustrates adjustment of values with the slider according to the second - embodiment. The moving of the focus (3) have the same effect on the adjustment E: values as in the first embodiment. Only the visual appearance of the sliding ~ 25 control is different. Now the slider (5) moves along the focus defined by the user, 3 so that the slider may move closer to and further away from the center (10). N Similar to the first embodiment changing between more precise and faster adjustment is based on the distance between the focus and the center (10).

Distance may be visualized by changing the appearance of the section of the radial line (9a) between the center and the slider (5). Figures 18-20 illustrate a third embodiment. Similar to the second embodiment, the slider track is not shown to the user. However, the control operations performed by the user are similar and have similar effects to the sliding control and to the parameter values as in the first embodiment. Figure 18 illustrates situation when the sliding control is not activated. When not activated, only the slider (5) shown on the display area (2). In this embodiment, the slider (5) is disposed at the center (10). Thus, the slider (5) also visualizes the center. An activation area (4) is defined in vicinity of the slider (5) which is not visible to the user. This enables the user to activate the sliding control even with a less accurate pointer, such as a hand or a finger. Graphical appearance of the slider (5) may include further indicators of the current radial angle. In this example, an arrow is shown in the slider (5) that shows the direction of the radial angle. Figure 19 illustrates the third embodiment when the user has activated the sliding control by activating it by touching the activation area (4) with his finger (8). As explained above, any other pointer may be used to indicate the focus (3) depending on the type of UI on which the sliding control is disposed. The radial line (9a) starting from the slider (5) and thus from the center (10) is shown. The = radial line (9a) may extend over the entire display area (2).

N N Figure 20 illustrates adjustment of values with the slider according to the third - embodiment. The moving of the focus (3) have the same effect on the adjustment E: values as in the first and second embodiments. Only the visual appearance of the ~ 25 sliding control is different. The slider (5) does not move away from the center 3 (10) but sticks at the center (10) and turns based on the focus (3) defined by the N user. Similar to the first embodiment changing between more precise and faster adjustment is based on the distance between the focus (3) and the center (10).

Distance may be visualized by changing the appearance of the section of the radial line (9a) between the center (10) and the focus (3). It is apparent to a person skilled in the art that as technology advanced, the basic idea of the invention can be implemented in various ways. The invention and its embodiments are therefore not restricted to the above examples, but they may vary within the scope of the claims.

[20]

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Claims

1. A sliding control for adjusting a value of a parameter via a computer- implemented user interface, the user interface comprising - a display apparatus configured to visually display a control element of the sliding control, and - an input apparatus configured to receive input from a user, the input from the user comprising a single, moveable focal point in an input area defined by the display apparatus, characterized in that - the sliding control comprises a first line indicating a radial direction from a fixed center along a plane defined by the display apparatus for visualizing an operative connection between the control element and the focal point, - movement of the focal point is configured to be projected to a movement of the control element of the sliding control on basis of a directional angle defined between a reference line in the plane traveling through the fixed center and the direction of the radial line defined by the focal point; and - adjusting the value of the parameter on basis of the movement of the control element. ® & & 2. The sliding control of claim 1, wherein moving the focal point towards W the fixed center is configured to increase speed of adjustment of the = value and moving the focal point away from the fixed center is = 25 configured to increase accuracy of the adjustment of the value of the 3 parameter.

N

3. The sliding control of claim 1 or 2, wherein the sliding control is activated when a predefined activation area is pointed by the user, and whereinthe first line appears in the user interface after activating the sliding control.

4. The sliding control according to any of claims 1 to 3, wherein the user interface provides visual, audible or haptic indicators indicating the value or a change of the value of the parameter.

5. The sliding control according to claim 4, wherein the visual indicators comprise at least one of a numerical value of the parameter and a visual indicator of direction of the first line shown in the control element.

6. The sliding control according to claim 4, wherein the audible indicator comprises an audible sound and at least one of the pitch, timbre, volume, tempo and direction of the audible sound is adjusted on basis of change of the value of the parameter.

7. The sliding control according to any of claims 1 to 5, wherein the user interface comprises a curved slider track along which the control element moves.

8. The sliding control according to claim 6, wherein the visual indicator © further comprises visual change of the curved slider track. & N

9. The sliding control according to any of claims 1 to 8, wherein the user a 25 interface comprises any one of a touch user interface, an augmented E reality user interface and a virtual reality user interface. 5 e

10. The sliding control according to any of claims 1 to 9, wherein the sliding > control is operable for adjusting value of a parameter related to any one of welding, carbon arc gouging and plasma cutting.

11. A method for adjusting a value of a parameter with computer- implemented sliding control disposed on a user interface, the method comprising: - visually displaying a control element of the sliding control on a display, and - receiving input from a user, the input from the user comprising a single, moveable focal point in an input area defined by the display apparatus, characterized by - indicating a radial direction from a fixed center along a plane with a first line for visualizing an operative connection between the control element and the focal point; - projecting movement of the focal point to a movement of the control element of the sliding control on basis of a directional angle defined between a reference line in the plane traveling through the fixed center and the direction of the radial line defined by the focal point; and - adjusting the value of the parameter on basis of the movement of the control element.

©

12. The method of claim 11, wherein moving the focal point towards the 2 fixed center is configured to increase speed of adjustment of the value N and moving the focal point away from the fixed center is configured to S increase accuracy of the adjustment of the value of the parameter. E 25 =

13. The method according to claim 11 or 12, further comprising activating 3 the sliding control by pointing a predefined activation area and S displaying the first line on the display only after activating the sliding control.

14. The method according to any of claims 11 to 13, further comprising providing in the user interface visual indicators indicating the value or a change of the value of the parameter.

15. The method according to claim 14, wherein the visual indicators comprise at least one of a numerical value of the parameter and a visual indicator of direction of the first line shown in the control element.

16. The method according to claim 14, further comprising providing an audible indicator indicating the value or a change in the value of the parameter, wherein the audible indicator comprises an audible sound and at least one of the pitch, timbre, volume, tempo and direction of the audible sound is adjusted on basis of change of the value of the parameter.

17. The method according to any of claims 11 to 16, wherein the user interface comprises a curved slider track along which the control element moves, and wherein the visual indicator further comprises visual change of the curved slider track.

18. The method according to any of claims 11 to 17, wherein the method is © operable for adjusting a value of a parameter related to any one of I welding, carbon arc gouging and plasma cutting.

N a 25

19. A computer program product having instructions which, when executed E by a computing device or system cause the computing device or system = to perform the method according to any of claims 11 to 18.

O 0 S

20. An apparatus comprising a computer program product according to claim 19 that causes the apparatus to be operable to perform the method according to the any of the claims 11 to 18.