DE10021450A1 - Method for controlling a one-dimensional cursor by evaluating the force exerted on a key - Google Patents

Abstract

The invention relates to a method for controlling a one-dimensional cursor by evaluating the force exerted onto a key. The aim of the invention is to develop a method for positioning a one-dimensional cursor on an axis and for activating functions using a keyboard. To these ends, the invention provides that the exerted pressure force is detected from a variable allotted pressure force, which is applied to a key in succession, and is then measured. The respective pressure value is determined using a table or by calculating a cursor position, whereupon the key operator alters this applied key pressure value if necessary, whereby once the desired pressure value is attained, an item of information regarding a selected function alternative or regarding a set value is fed to the further processing once operation of the key is completed. According to the inventive method for controlling a cursor using a key, the pressing force thereof is measured and is evaluated using a FIFO buffer. The position of the cursor is directly dependent on the amount of force exerted and can be varied as desired.

Description

The present invention relates to a method for Cursor control using a button, its pressing force is measured and evaluated with a FIFO buffer. The Cursor position is directly dependent on the force exerted and can be varied as required without waiting. The The method can be used both for the continuous adjustment of Parameters as well as for function selection.

Devices with electronic control by people can be operated or configured, such as. B. Car radios, video recorders, photocopiers, cameras, etc. today usually have a display and a Input medium such as B. a keypad.

A standard task of such devices is the selection of functions or the setting of parameters (menu selection, setting brightness levels, selection of a month for the date setting). The possibilities of the user interface result from the technical basis of your hardware; for the input media these include buttons, computer mice, touch screens, rotary wheels and pressure sensors:

• - A menu control with ordinary buttons offers simple way a large number of functions; however this requires longer key sequences. Such Menu controls usually have the Forward keys, Back, selection and cancel. A menu control with four Arrow keys plus activation key is z. B. in patent US 6047197 (company Ericsson, 1996/2000).
• - In contrast to buttons, computer mice have Menu controls via a separate cursor, the Cursor. Computer mice allow an X-Y Positioning and function activation via Mouse buttons.
• - Digital rotary wheels in the form of volume controls or Rollers allow continuous values on one individual axis. If you are with a additional activation button can be provided Rotary wheels also for selecting software functions be used.
• - Pressure sensitive buttons can a. with piezo Sensors and so-called Force Sensing Resistors (force-dependent Realize resistors, FSR). FSRs take up little space and can be produced in various forms. The the force exerted is not retained when you let go.

The following patents relate to user interfaces with pressure sensors:

• - The patent JP 0040319719 AA (company NEC, 1991/1992) describes an input system in which keys depend on the hand pressure applied either the function "Scroll line by line" or with increased pressure Fulfill "page by page". For cursor control such keys must be used and used in pairs (forward and backward movement).
• - In the US 5675329 (IBM, 1996/1997) the Pointed out the velocity on a  normal typewriter keyboard with pressure sensors measure in order to realize a second function.
• - The patent US 5396235 (Canon, 1992/1995) shows the Setting the contrast and magnification level of one Photocopier by means of pairs Piezo sensors. The contrast setting is on a The scale signals that the pressure changes depending on the pressure Contrast value in steps of one or five.
• - The patent US 5184120 (Motorola 1991/1993) demonstrates a function selection using FSR. Before the Application, the sensor is calibrated, then the one action at different pressure levels assigned. Depending on the proof, some appear Menu items. To activate a menu entry, the Users print the proof for a set period of time keep constant.
• - The patent DE 196 09 026 C2 (Loewe company, 1996/1998) describes a sensor bar for setting analog Values such as B. Volume that is next to a keyboard located. In contrast to FSR, the position of the Pressure a role and not the force.

Known adjustment mechanisms with their technical features are listed in the table in FIG. 1. Line b is realized, inter alia, by the Ericsson patent mentioned. Line f refers to the patents mentioned by NEC and Canon, line g corresponds to the Motorola and h to the Loewe patent.

The column "stepless" describes the criterion whether a continuous adjustment is possible or only in steps. "Set" describes whether the mechanism for setting Parameters. By "selection" it is meant whether a Activation of functions such as B. menu entries is possible.

Most designs provide the operator with one visible or audible feedback ("Feedback") on your Activities that manipulate the mechanism significantly facilitated. While this feedback relates directly to the Related input, the visible "result" is the result of Processing by microprocessors. The entries can be a Describe position on one or two "axes", ie one  Point on a line (e.g. rotary adjuster) or on one Area (e.g. mouse pointer).

The comparison shows that simple Arrow keys already very powerful controls enable. However, they reach their limits when it comes to Selection of a large number of alternatives is possible. The mouse is the most powerful instrument in the overview. Wheels are well suited for infinitely variable settings, the selection of Functional alternatives, however, require an additional button for confirmation.

The mechanics of pressure sensors do not provide any feedback like buttons, knobs or mice. In the case of Fig. 1f and Fig. 1g, an operator can therefore only roughly estimate the applied force. The bar that in Fig. 1f z. B. expresses the set contrast, is no help since the pressure applied does not correspond to the size of the bar, but only controls the rate of change of the bar.

The sensor menu described in FIG. 1g also does not provide any feedback on the force exerted. The resulting action appears as the result of an invisible process because the actions are arranged in an arbitrary order. If you don't know this sequence by heart, you have to try several times.

In the sensor strip of FIG. 1h results in the feedback of the finger position. This sensor-bar mechanism can be used in many ways in combination with a keyboard and the operation can be as simple as with the rotary adjuster. However, the bar requires an area that corresponds to an entire row of buttons.

In summary, it can be said that the known adjustment mechanisms with pressure sensors lag behind the other solutions in terms of ease of use because they offer no feedback on the force exerted. The new method described below corresponds to Fig. 1i.

The invention aims to control a cursor with keys small space, on a quick and easy to understand Usability as well as with little equipment low manufacturing costs and energy-saving operation.

The invention has for its object a method for Positioning of a one-dimensional cursor on an axis as well as for function activation using a keyboard develop.

The task is performed by those mentioned in the characterizing part Features of the independent claims solved.

If a button is pressed, the control is set to Gear. The cursor is on a scale depending on the force exerted positioned, similar to a scale. The person who The method used can be based on the cursor feedback Increase or decrease the pressing force until the desired one Position is reached. By releasing the button, a Function activated with the position of the cursor is associated.

The invention aims at three different Embodiments are explained in more detail. In the associated drawing show:

Fig. 2 is a dimmer (brightness adjuster for lighting),

Fig. 3 shows a screen with an underlying toolbar for menu control,

Fig. 4 is an electronic dictionary in the form of a ballpoint pen with an LCD display and

Fig. 5 shows the flow chart of the control software.

In the example of FIG. 2, the method allows a brightness controller to be set up using an FSR (Force Sensing Resistor) plus electronic control. After pressing the key (pressing the FSR), the cursor is positioned in the form of a dot on the display scale according to the force exerted, thus signaling the intended brightness setting. The cursor follows the force exerted with a delay of a fraction of a second:
When the force is increased, the cursor moves to the right. When the force is released, the cursor moves to the left. The previously set brightness is indicated by a constant bar display (the filled part of the scale). In the example, the brightness is increased from 30% to 60%.

To switch the lamp to full energy, a short, strong pressure. One is enough to switch off the lamp short, light touch.

In the example of Fig. 3, the method is used to set up a menu control with a few buttons, which is as powerful and fast as a control with a computer mouse pointer: If one of the buttons A to D is pressed, a cursor appears in the form of a horizontal one Bar on the associated screen menu A, B, C or D. When pressed lightly, the cursor points to the lowest empty entry. An increased pressure moves the cursor continuously according to the pressure to the higher menu entries, while a slow release moves the cursor back down. If the button is suddenly released, the menu entry under the cursor is selected and a function is triggered if necessary. The combination of n keys offers n-fold, one-dimensional cursor control.

In the example of FIG. 4, the method enables a miniaturized electronic dictionary in pen form with an FSR key as the only control element. Instead of the pressure mechanism of a ballpoint pen, the FSR is housed here. In order to retrieve an entry from the dictionary, pressure is applied to the FSR. A slight pressure moves a cursor in the form of a small rectangle to the beginning of the alphabetical scale, while an increased pressure moves the cursor continuously backwards.

Since there are more entries than with an FSR convenient can be distinguished, the key must be pressed several times become. Through four selection processes with z. B. 26, 20, 20 and 10 Alternatives can be 26 × 20 × 20 × 10 = 104,000 entries distinguish; that's enough for an electronic Dictionary.  

A complete dimmer would not be possible without a single FSR build the procedure described here, or it would be one longer operating sequence necessary. Here the procedure allows one mechanically more stable and space saving construction in the Compared to knobs. Compared to a known one Dimmer control by a single button (as long as the button is held down, the light becomes bright and repeated darkened, the set level remains when released received) this new control is faster and more precise.

In the case of the on-screen menus, this can be done without this described method with conventional buttons only one Reaching menu selection through numerous steps is common a selection with arrow keys and an OK key. The new The process here makes it easier and faster Service.

Entries can be found more quickly in the pen dictionary than in a printed book, but slower than with one large keyboard. With conventional technology, without this described method could be an electronic dictionary cannot be meaningfully constructed in pen form. Here The invention thus enables a particularly small design.

The three examples, as different as they are, all benefit the same procedure for positioning a cursor using a variable pressure. The mechanical and electrical Constructions can vary widely; FSR can be used become or other types of sensors; it can be a single sensor can be used with a digital row of buttons or a Group of sensors, that plays for the principle of the method not matter.

People can use their fingers to set a variable force of approx. Exercise 10 g up to approx. 1500 g, but you can do this only roughly dose. Without feedback, people can only Operate a few levels reliably, such as "strong", "easy" and press "very lightly". The situation changes when People a quick visual or acoustic feedback get: Now most people can get without Difficulties e.g. B. on a scale a desired pressure  Exercise down to a few grams and for several seconds maintain.

The quick feedback is called "cursor" here. This term describes an electronic image of a state that can be moved back and forth quickly within a dimension. Examples of cursors are, for example, cursors of a word processor, mouse pointer, the scroll bar of the window of a Windows software, the highlighting of a menu entry within a menu control. Such cursors are characterized by the following features:

• - The cursor is always visual or during operation acoustically perceptible, it is outside the operating phase invisible or in a resting position
• - The position can be changed at any time at short notice
• - the cursor can jump, if not as quickly as desired (e.g. word by word in a word processor)
• - The cursor can be controlled by an electronic control manipulate directly, exactly per control mechanism a cursor exists
• - All cursor positions can be clearly and obviously assign to an order
• - the cursor moves in one or more dimensions between the minimum and maximum positions (e.g. One-dimensional scroll bar, two-dimensional mouse pointer)

As a cursor z. B. a rectangular frame Defining the image section of a digital camera, or the level of the continuous tone of a technical tone generator, or the brightness of a light source, if each of perceived and manipulated directly by an operator can.

On the other hand, in this sense there would be no cursor: the Image section of a motorized zoom lens (no electronic image), or the volume of one Stereo system (irregular sound source does not allow a clear one Position), or the one moving in a virtual landscape Character of a computer game (the position is determined by Game functions influenced outside of the control of the Operator).  

The cursor used in this invention has a "Inertia", i.e. H. a fractional delay in movement of seconds. This simulates the clumsiness of material objects and thus contributes to a natural acting movement. At the same time, it enables the controller to between a gradual release (= move cursor back) and a quick release (= finger is released from the button taken, accept attitude). The Inertia can vary in severity, depending after whether the pressure is increased or decreased. Often it will make sense to increase the inertia less when increasing the pressure take into account (rapid increase, slow decrease).

In addition to the examples mentioned, there are many other applications conceivable, for example on the keypad of a microwave oven or on Lever of a motor vehicle steering wheel. Where a visible cursor is inappropriate, for example for disabled users or drivers of a vehicle, the method can be an acoustic position Use feedback, e.g. B. over a sequence of different Tones depending on position.

With the method designed according to the invention, a Cursor positioned much easier and faster than with the usual multiple actuation of digital keys. Compared to a simple digital key query (Scan matrix and debounce keys) higher software effort falls with today's high-performance control electronics don't matter.

In comparison to rotary controls, touch screens, etc., this allows Processes that supplement the conventional design of keyboards a sensor function and electronic evaluation also for very powerful devices to use. That enables one small design, robust construction and reasonable price.

The short actuation path of a pressure sensor allows one very quick operation; and the procedure described here does not limit this by time constraints. So inexperienced Users use the system carefully and slowly while experienced users can work with it much faster, similar to the practice of using a computer mouse. The while  cursor visible when pressed never leaves doubts about the System state arise.

The invention differs from the known solutions by the following features:

• - While a single pressure sensor for any Positioning the cursor is sufficient, several can Buttons can be combined with a pressure sensor. Thereby is the procedure in both simple and in complex devices.
• - Since the cursor is positioned directly according to the pressure will (instead of just moving speed vary), the system always delivers an exact Feedback on the pressure applied. Only this makes it possible precise and quick positioning.
• - There are no waiting times such as B. the key Repetition rate of a common keyboard, but each Position can be controlled without detours and then be activated immediately. The only delay is one low inertia of the cursor movement, which, however, the Operation not difficult, on the contrary simplified. The activation is at any time by releasing possible.
• - A single pressure sensor can be used for a forward and backward movement as well for the functional Activation can be used and thus replaces three buttons a common keyboard. This enables smaller devices.
• - The method can both be used to set parameters as well as for the selection of situation-dependent software Menus can be used with a uniform system. The allows the same hardware for different Use purposes and standardize the operation.

When a button is pressed, the control starts (see Fig. 5):

• 1. First, an assignment function f (force) is defined, ie a resulting position is defined for each possible contact force. In the simplest case, this is constant and is immutablely installed in a device. If necessary, however, flexible adaptation is also possible ( 1 a is optional), in that the assignment function is only determined immediately before the positioning process.
• 2. Immediately after the mechanism is triggered by touch the cursor appears at the position that is minimal Pressure corresponds. The cursor can be a point on a Line, as a line on a surface or as a surface in one three-dimensional space and optically or be acoustically reported.
• 3. A FIFO buffer (First In, First Out) is provided and initialized. This buffer is dimensioned so that it can take as many measurements as within one typical response time. At 50 measurements per The buffer would have a second and a response time of 0.2 s thus 0.2.50 = 10 entries.
• 4. The pressure exerted on the key is then queried (about 20-100 × per second).
• 5. Each queried value is evaluated by assigning the registered force to a position. This is done by applying the assignment function determined in 1 a to the measured force.
• 6. The controller uses the last measured value to check whether the button has been released. If this is the case, the method continues with step 10 . As long as the button is held down, the process repeats steps 4 , 5 , 6 , 7 , 8 and 9 .
• 7. The position determined in 5 is saved in the FIFO buffer, at the same time the oldest entry is removed from the buffer. In this way, the last x positions are always retained, where x describes the size of the buffer (x <= 2 applies).
• 8. The cursor positions in the FIFO buffer become one moving average formed. This prevents tremors of the cursor and causes a low inertia of the Movement that simulates mechanical movement (similar the clumsiness of a pointer measuring instrument).
• 9. The cursor is moved to the mean position calculated in step 8 . With an acoustic cursor, the z. B. happen over a variable pitch. The process then continues with step 4 .
• 10. After the button is released, the button disappears Cursor.
• 11. If the cursor pointed to a menu or similar, the selected function alternative determined. If the cursor a value such as B. marked a brightness level, the corresponding value is determined.
• 12. The value determined in step 11 or the function alternative is now only implemented, ie the selected menu item, the set brightness or the like is activated.

The assignment function mentioned in step 1 can either z. B. calculated with a polynomial function or taken from tables. This assignment of the force to a cursor position must be designed in such a way that it appears natural and can be operated intuitively. The minimum and maximum applicable force results from the mechanical design and can be in the range of 50 to 1500 g. However, the maximum force is only assigned to the maximum cursor position if a wide area is to be used (e.g. large screen), otherwise an easier to use average force corresponds to the maximum cursor position.

According to individual habits, one can Adjustment via software can be provided. So it can be Adjust the pressure harder or softer within narrow limits. People with stronger hands usually only become one Prefer stronger attitudes, while more sensitive and practiced Users will choose a gentler response (similar to the Speed setting of a computer mouse). Likewise can the sluggishness of the cursor is slightly user-specific can be varied (similar to the double-click setting for a Computer mouse).

Some cursor positions are assigned to the cancel function, for example a first empty menu entry without effect. So you can test an open menu by lightly touching it open or close by slowly releasing if none of the offered alternatives is desired. In the case of  Dimmer, the brightness can remain unchanged when the Cursor appears at the previously set position.

With this new cursor control a single Pressure sensor thus perform all functions for which with a conventional keyboard several keys (+, -, OK and cancel) and longer key sequences (multiple + / i, then OK or cancel) are needed.

Claims (12)

1. A method for controlling a cursor by means of a key, characterized in that a variable, metered pressure force is exerted on the key, the pressure force applied is detected and measured by a sensor, and the measured pressure value is assigned on the basis of a table or by calculation of a cursor position the cursor is positioned according to this calculation, whereupon the operator of the key changes the applied pressure value for the key if necessary, and after reaching the desired cursor position after the operation of the keys has ended, information about a selected function alternative or a set value of the others Processing is fed. 2. The method according to claim 1, characterized in that the position of the cursor visually using a Movable marking is done on a display.   3. The method according to claim 1, characterized in that the position of the cursor optically by means of proportional adjustment of the brightness of a Light source takes place that is directly perceptible Environment of the operator. 4. The method according to claim 1, characterized in that the position report of the cursor acoustically by a Tone sequence or frequency occurs in the audible range. 5. The method according to claim 1 to 4, characterized in that the position of the cursor is acoustically one Alternative function or a value is assigned which is reported back by a synthetic voice. 6. The method according to claim 1 to 5, characterized in that the cursor movement with a perceptible sluggishness is equipped with minimal intensity, which by the Position determination based on the calculation of a sliding Average value of the pressure measurement values using a FIFO Buffer (first-in-first-out buffer) is brought about. 7. The method according to claim 1 to 6, characterized in that that with a button both the direction, speed as well as the position of the cursor is controlled. 8. The method according to claim 1 to 7, characterized in that that a quick release of the button is a function or activates a value that is visible or audible Cursor position is assigned. 9. The method according to claim 1 to 8, characterized in that a slow withdrawal of the pressure on the button the selection of visible or audible functions or values canceled.   10. The method according to claim 1 to 9, characterized in that that after the operation of the button ends the cursor disappears or to a rest position at the end of the scale is moved. 11. The method according to claim 1, characterized in that a single key is used for cursor control. 12. The method according to claim 1, characterized in that a group of keys is used for cursor control, where a maximum of one cursor is visible that the assigned button is assigned.