JPH08263200A - Coordinate input device - Google Patents

Abstract

PURPOSE: To easily and stably obtain vector information corresponding to the operation of an operation part in any direction by adjusting the resistance value of a load resistance connected to a pressure resistance varying element so that the state of an output voltage from a detecting circuit meets specific requirements. CONSTITUTION: A control circuit 300 selects a proper load resistance out of load resistances 121(1), 121(2),..., 121(n) according to the output voltage supplied from the detecting circuit. Information on the selected load resistance is supplied from the control circuit 300 to an arithmetic circuit 300. The arithmetic circuit 400 determines the moving speed of a cursor on the basis of pressure determined with the information on the load resistance and computes the horizontal and vertical components of the moving speed of the cursor from the output voltage from the detecting circuit consisting of the load resistance and respective pressure resistance varying elements 120(a), 120(b), 120(c), and 120(d). Consequently, the moving speed of the cursor to the pressure is always stable in any direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device for designating the position of a cursor or the like in a display unit of a computer system, a so-called pointing device.

[0002]

2. Description of the Related Art Conventionally, there has been known a pressure detection circuit configured as shown in FIG. 4 using a pressure resistance change element whose resistance value changes according to pressure. In this pressure detection circuit,
The pressure resistance change element 120 and the load resistance 121 are connected in series between the power supply line and the ground line, and the output voltage V _out appearing at both ends of the pressure resistance change element 120 is used as a detection voltage. The resistance value of the pressure resistance change element 120 changes according to the applied pressure F, and as a result, the divided voltage between the resistance value and the resistance value of the load resistance 121, that is, the output voltage V
_OUT changes. Therefore, this output voltage V _OUT represents the pressure F applied to the pressure resistance change element 120.

By the way, the pressure-resistance characteristic of the pressure resistance change element 120 is not a linear characteristic as shown in FIG. Further, in the pressure detection circuit shown in FIG. 4, the relationship between the resistance value R _x of the pressure resistance change element 120 and the output voltage V _OUT is not a linear relationship as shown in FIG. Therefore, the output characteristic of this pressure detection circuit, that is, the relationship between the pressure applied to the pressure resistance change element 120 and the output voltage V _OUT is as shown in FIG. 7.

A coordinate input device using such a pressure detection circuit is conceivable. This coordinate input device specifies the cursor position of the display unit in the computer system. Then, the movement speed of the cursor can be controlled according to the pressure detected by the pressure detection circuit.

The coordinate input device (pointing device) 100 is constructed, for example, as shown in FIGS. 9 (a) and 9 (b). The operation stick 101 is shown in FIG.
As shown in FIG. 4, the joystick is provided at the center of the base 102 with the degree of freedom of operation so that it can be tilted in all directions. In the base 102, as shown in FIG.
Four pressure resistance change elements 120 (a), 120 (b),
120 (c) and 120 (d) are arranged so as to surround the operation stick 101. Then, the pressure resistance change element 12
0 (a) and 120 (c) are arranged on the x-axis corresponding to the horizontal axis of the display screen, and pressure resistance changes 120 (b) and 1
20 (d) is arranged on the y-axis orthogonal to the x-axis.

The pressure resistance change elements 120 (a), 120 (b), 120 arranged in the substrate 102 as described above.
(C) and 120 (d) are connected to the arithmetic circuit 200 as shown in FIG. In this arithmetic circuit 200, each pressure resistance change element 120 (a), 120 (b), 120
Four detection circuit systems are provided corresponding to each of (c) and 120 (d), and each of them has the detection circuit shown in FIG. The arithmetic circuit 200 calculates, for example, the position and movement speed of the cursor based on the output voltage from each detection system, and provides the information to the computer system.

For example, as shown in FIG. 9B, when the operating stick 101 is operated by the force Fa in the positive direction of the x-axis, the resistance value of the pressure resistance changing element 120 (a) which receives the pressure Fa corresponds to the resistance value. Information on the position and movement speed of the cursor in the horizontal direction of the display screen is calculated based on the output voltage. Further, when the operation stick 101 is operated with the force Fb in the positive direction of the y-axis, the cursor in the vertical direction of the display screen is based on the output voltage corresponding to the resistance value of the pressure resistance change element 120 (b) receiving the pressure Fb. The information of the position and the moving speed of is calculated. Further, for example, when the operation stick 101 is operated by the force Fc in the direction of 45 ° with respect to the positive directions of the x-axis and the y-axis, the resistance value of the pressure resistance change element 120 (a) receiving the pressure Fc · cos θ. The moving component of the cursor in the horizontal direction of the display screen is calculated based on the output voltage corresponding to, and based on the output voltage corresponding to the resistance value of the pressure resistance change element 120 (b) receiving the pressure Fc · sin θ. , The moving component of the cursor in the vertical direction of the display screen is calculated.

[0008]

As described above, the output characteristics of the above four detection systems are non-linear characteristics as shown in FIG. Therefore, when the output voltage from each detection system when the operation stick 101 is operated in all directions with a constant force is plotted, a locus as shown in FIG. 8 is obtained. In FIG. 8, when pressure is applied to the pressure resistance change elements 120 (a) and 120 (b) arranged as shown in FIG. 10, points corresponding to the respective output voltages are plotted in the region I, and the pressure resistance change element 120 is plotted. When pressure is applied to (b) and 120 (c), points corresponding to the respective output voltages are plotted in the area II, and the pressure resistance change elements 120 (c) and 120
When pressure is applied to (d), points corresponding to each output voltage are plotted in the region III, and the pressure resistance change element 120
When pressure is applied to (c) and 120 (a), points corresponding to each output voltage are plotted in the area IV. In the output characteristic shown in FIG. 7, in the pressure range where the relationship between the pressure and the output voltage is relatively linear (medium pressure), the locus plotting each output voltage is substantially the same as Q2 shown in FIG. It becomes circular, but its locus is close to rectangular in the high pressure range.
In the low pressure range, the locus becomes Q3, which is close to a star shape.

Therefore, since the relationship between the magnitude of each output voltage and the direction of pressure differs depending on the magnitude of pressure, an accurate moving speed and moving direction cannot be obtained. By performing a complicated function conversion in consideration of the characteristics of the pressure resistance change element, it is possible to make the locus plotting each output voltage described above close to a circle for any pressure. ,
It is not possible to accurately obtain the moving speed and the like due to variations in element characteristics.

Therefore, an object of the present invention is to provide a coordinate input device capable of easily and stably obtaining vector information such as a moving speed of a cursor corresponding to an operation of an operation unit such as an operation stick in all directions. That is.

[0011]

In order to achieve the above object, the present invention, as described in claim 1, provides vector information corresponding to the operating force of an operating portion operable in various directions. In the coordinate input device for generating, a plurality of pressure change elements which are arranged at predetermined positions and which receive a pressure associated with the operation of the operation section, and a load resistance connected to the pressure change element are included. A pressure resistance change element whose value changes, a detection circuit that outputs an output voltage based on the divided voltage by the load resistance, and the pressure resistance change so that the state of the output voltage from the detection circuit satisfies a predetermined condition. Resistance adjusting means for adjusting the resistance value of the load resistance connected to the element,
The adjusted load resistance has a calculation means for calculating vector information corresponding to the operation pressure of the operation section based on the output voltage from the detection circuit in the state where the load resistance is connected to the pressure resistance change element. .

Further, from the viewpoint that the vector information in a uniform state can be obtained with respect to the force applied to the operating portion in all directions, the resistance adjusting means operates in all directions. It has a means for adjusting the load resistance so that the magnitude of the vector whose component is the output voltage obtained from the detection circuit for each pressure resistance change element is within a predetermined range for the same pressure from the section. .

Further, from the viewpoint that stable vector information can be obtained even if the force applied to the operating portion is small, the resistance adjusting means is a detection circuit when the operating portion is operated. There is provided a means for changing the resistance value of the load resistance depending on whether or not the magnitude of the vector having the output voltage as a component is smaller than a predetermined value.

Further, from the viewpoint that the load resistance can be easily adjusted, as described in claim 4, the detection circuit includes a plurality of load resistances having different resistance values, and the resistance adjusting means includes the plurality of load resistances. A resistance switching means for selecting a load resistance to be connected to the pressure resistance change element from the load resistance is provided.

[0015]

When the operating portion is operated with a certain force, a force corresponding to the operating direction is applied to each pressure resistance changing element, and an output voltage corresponding to each pressure resistance changing element is obtained from the detection circuit. Then, the resistance adjusting means adjusts the resistance value of the load resistance so that the state of the output voltage satisfies a predetermined condition, for example, the magnitude of a vector having each output voltage as a component falls within a predetermined range. To do. Then, the calculation means calculates vector information such as the moving speed of the cursor based on the output voltage from the detection circuit in the state where the adjusted load resistance is connected to the pressure resistance change element.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the mechanical structure of the coordinate input device is the same as that shown in FIG. 9, and four pressure resistance change elements 120 (a), 120 (b), 120 (c), 1
20 (d) are arranged on the x-axis and the y-axis which are orthogonal to each other.

The four pressure resistance changing elements 12 as described above
0 (a), 120 (b), 120 (c), 120 (d)
Are connected to a circuit as shown in FIG. In FIG. 1, each pressure resistance change element 120 (a), 120 (b),
One end of 120 (c), 120 (d) has n load resistors 1
21 (1), 121 (2), ..., 120 (n) are connected in parallel. In addition, each pressure resistance change element 12
0 (a), 120 (b), 120 (c), 120 (d)
The other end of is connected to the ground line (GND) via each select terminal of the selector 150. Further, each load resistance 121 (1), 121 (2), ..., 120 (n)
Are switching transistors Tr (1), Tr
(2), ..., Power line Vcc via Tr (n)
It is connected to the. Transistor T for each switching
, r (n) are connected to a control circuit 300, and from this control circuit 300, switching transistors Tr (1), Tr (2), ...
A switching signal for switching ON / OFF of Tr (n) is supplied.

From the control circuit 300, the selector 1
A selection signal is supplied to 50, and in response to this selection signal, the selector 150 causes the pressure resistance change element 120 (a),
Any one of 120 (b), 120 (c) and 120 (d) is selectively connected to the ground line (GND). Each pressure resistance change element 120 (a), 120 (b), 120
(C), 120 (d) and load resistors 121 (1), 12
The voltage appearing at the connection point of 1 (2), ..., 120 (n) is supplied to the control circuit 300 as an output voltage. That is, in such a circuit configuration, the pressure resistance change elements 120 (a), 120 (b), 120 (c),
With one of 120 (d) selected, load resistances 121 (1), 121 (2), ...
.., 120 (n) is connected to the power supply line Vcc, the detection circuit shown in FIG. 4 is configured, and the output voltage thereof is supplied to the control circuit 300.

Based on the output voltage from the detection circuit supplied as described above, the control circuit 300 sets appropriate load resistances to the load resistances 121 (1), 121, as will be described later.
(2), ..., 120 (n) are selected. Information on the selected load resistance is sent from the control circuit 300 to the arithmetic circuit 4
00 is supplied. The arithmetic circuit 400 determines the moving speed of the cursor based on the pressure determined from the information of the load resistance, and the load resistance and each pressure resistance change element 120.
The horizontal and vertical components of the moving speed of the cursor are calculated based on the output voltage from the detection circuit composed of (a), 120 (b), 120 (c), and 120 (d).

The above-mentioned control circuit 300 and arithmetic circuit 400
Executes the process in the procedure shown in FIG. When the operator operates the operation stick 101 with a certain force in a certain direction, the control circuit 300 operates the selector 150 based on the selection signal in a state where one switching signal is enabled and one corresponding load resistance is selected. The pressure resistance change element selected by is sequentially switched. In the process, the control circuit 3
00 is each pressure resistance change element 120 (a), 120
The output voltages from (b), 120 (c) and 120 (d) are read (S301). Then, the read pressure resistance change elements 120 (a), 120 (b), 120 (c),
Based on the output voltage from 120 (d), the output voltage region shown in FIG. 8 is determined (for example, when the force Fc acts,
The output voltage is obtained from the pressure resistance change elements 120 (a) and 120 (b)), and the combined value R is obtained from the voltage value.

[0021]

[Equation 1]

The calculation is performed according to (S302). In the above equation, X is the output voltage of the pressure resistance change element on the x axis, and Y is the output voltage of the pressure resistance change element on the y axis.
Here, regarding the detection circuit configured as shown in FIG. 4, when the value of the load resistance is changed, the output voltage value thereof changes. As a result, the relationship between pressure and output voltage also changes. Therefore, a certain load resistance determines the pressure range in which the locus of the plot of the output voltage shown in FIG. 8 becomes substantially circular.

Ra is the lower limit of the combined value of the output voltages corresponding to the pressure value that draws the locus which is allowed as a circle, and R is the upper limit thereof.
If b, it is determined whether the calculated combined value R is between the lower limit Ra and the upper limit Rb (S303). If the combined value R is not between the lower limit Ra and the upper limit Rb, the control circuit 300 changes the effective switching signal to change the pressure resistance change elements 120 (a), 120 (b),
The load resistance to be connected to 120 (c) and 120 (d) is changed (S304). Then, the above processing is performed. As a result, even in the same pressure state, the pressure resistance change elements 120 (a), 120 (b), 120 (c), 120 to be read.
The output voltage from (d) changes (S301). Then, the combined value R of the output voltages is further calculated (S30
2).

Such processing is repeated until the combined value R of the output voltages falls within the range of the lower limit Ra and the upper limit Rb. Information on the load resistance value when the combined value R of the output voltage is between the lower limit Ra and the upper limit Rb is provided from the control circuit 300 to the arithmetic circuit 400.
Is supplied to. As described above, since the load resistance R _L determines the pressure range in which the locus of the plot of the output voltage becomes substantially circular, the arithmetic circuit 400 is applied to the operation stick 101 based on the load resistance determined as described above. Recognize pressure. Specifically, a predetermined load resistance R
_The pressure corresponding to the selected load resistance R _L is searched with reference to the table showing the relationship between _L and the pressure (S40).
1). Then, the moving speed (absolute value) of the cursor corresponding to the pressure is further determined (S402). The moving speed of the cursor corresponding to this pressure is determined, for example, according to a table in which the relationship between the pressure and the moving speed determined in consideration of operability, visibility, and the like is predetermined.

Then, the arithmetic circuit 400 reads each pressure resistance change element 120 read from the determined moving speed in a state in which the load resistance determined as described above is selected.
The horizontal and vertical moving speed components (vector information) of the cursor are calculated based on the output voltage ratios from (a), 120 (b), 120 (c), and 120 (d) (S40).
3). The calculated horizontal and vertical movement velocity components of the cursor are transferred to the display unit of the computer system.

As described above, according to this embodiment, the pressure resistance change elements 120 (a), 120 (b), 1 in all directions with respect to the force applied to the operation stick 101 are
The pressure resistance change elements 120 (a), 120 (b), 1 are calculated from the moving speed of the cursor determined when the loci of plots of the output voltage from 20 (c) and 120 (d) are close to a circle.
Since the horizontal and vertical components of the moving speed of the cursor are calculated based on the output voltage ratio from 20 (c) and 120 (d), the moving speed of the cursor with respect to the pressure is always stable in all directions. .

By the way, each pressure resistance change element 120 (a), 120 (b), 120 (c), 120 shown in FIG.
From the locus of the plot of the output voltage from (d), when the pressure applied to the operation stick 101 is particularly small, each pressure resistance change element 120 (a), within the range of about ± 10 ° with respect to the x axis and the y axis, 120 (b), 120 (c), 12
The output voltage level from 0 (d) may be too small to recognize the pressure applied to the operation stick 101. In such a case, it is possible to change the detection range by changing the load resistance.

In this case, for example, by the circuit shown in FIG. 3, the pressure resistance change elements 120 (a), 120 (b),
The load resistance value connected to 120 (c) and 120 (d) can be changed. Note that FIG. 3 shows a circuit for one pressure resistance change element 120, and in actuality, similar to FIG. 1, the connection of each pressure resistance change element is switched or each pressure resistance change element is switched. A plurality of circuits of similar configuration are provided for the change element.

In FIG. 3, the first load resistor 121
(1), the second load resistance 121 (2) and the pressure resistance change element 120 are connected to the power supply line Vcc and the ground line GND.
Are connected in series, and both ends of the first load resistor 121 (1) are configured to be bypassed by the transistor Tr. The base of the transistor Tr and the output terminal of the pressure resistance change element 120 are connected to a control circuit (not shown) as shown in FIG. Then, normally, the transistor Tr is turned off, and the series combined resistance value of the first load resistance 121 (1) and the second load resistance 121 (2) is connected to the pressure resistance change element 120 as a load resistance value. Then, an arithmetic circuit (not shown) calculates the moving speed of the cursor for each of the horizontal and vertical components based on the output voltage from the pressure resistance change element 120. On the other hand, when the control circuit determines that the size of the vector having the output voltage from each pressure resistance change element 120 as a component (calculated based on the above Equation 1 and corresponding to the pressure) is smaller than the predetermined value, the switching signal is valid. Then, the transistor Tr is turned on. As a result, the first load resistor 121 (1) is short-circuited, and as a result, with only the second load resistor 121 (2) connected to the pressure resistance change element 120, the arithmetic circuit changes the pressure resistance change. The moving speed of the cursor is calculated for each of the horizontal and vertical components based on the output voltage from the element 120.

In the above embodiment, the pressure applied to the operation stick 101 is small, and the pressure resistance change element 120 is used.
When the output voltage of is small, the substantial load resistance value connected to it is made small, so that the output voltage becomes large. Therefore, each pressure resistance change element 120 (a), 120 (b), 120 (c), 120 in the actual device
In the state where the locus of the plot of the output voltage in (d) approaches from Q1 to Q2 shown in FIG. 8, the moving speed of the cursor can be calculated.

The configuration shown in FIG. 3 can also be applied to the device shown in FIG. 1 if it is changed so as to switch n load resistors connected in series.

[0032]

As described above, according to the present invention, when the operating portion is operated with a certain force, the state of the output voltage from the detection circuit corresponding to each pressure resistance change element satisfies the predetermined condition. The resistance value of the load resistance is adjusted to
Since the vector information is calculated based on the output voltage from the detection circuit in the state in which the adjusted load resistance is connected to the pressure resistance change element, in all directions of the operation unit,
If the applied forces are the same, vector information having substantially the same magnitude can be obtained, and a stable calculation result can be obtained.

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention.

FIG. 2 is a flowchart showing operations of a control circuit and an arithmetic circuit shown in FIG.

FIG. 3 is a circuit diagram showing a main part of another embodiment of the present invention.

FIG. 4 is a circuit diagram showing a basic configuration of a pressure detection circuit.

FIG. 5 is a diagram showing characteristics of a pressure resistance change element.

FIG. 6 is a diagram showing a relationship between a resistance value of a pressure resistance change element in a detection circuit and an output voltage.

FIG. 7 is a diagram showing output characteristics of a detection circuit.

FIG. 8 is a diagram showing an output voltage characteristic of a detection circuit.

FIG. 9 is a diagram showing a structure of a coordinate input device.

FIG. 10 is a diagram showing a basic configuration of a detection system of the coordinate input device.

[Explanation of symbols]

100 Coordinate Input Device 101 Operation Stick 102 Bases 120 (a), 120 (b), 120 (c), 120
(D) Pressure resistance change element 121 (1), ... 121 (n) Load resistance 150 Selector 300 Control circuit 400 Operation circuit

Claims (4)

[Claims] 1. A coordinate input device for generating vector information according to an operation force of an operation section that can be operated in various directions, and a plurality of pressures that are arranged at predetermined positions and receive a pressure associated with the operation of the operation section. A variable resistance element, a pressure resistance variable element including a load resistance connected to the pressure variable element, the resistance value of which changes in response to a received pressure, and a detection circuit which outputs an output voltage based on a divided voltage by the load resistance. Resistance adjusting means for adjusting the resistance value of the load resistance connected to the pressure resistance change element so that the state of the output voltage from the detection circuit satisfies a predetermined condition, and the adjusted load resistance adjusts the pressure A coordinate input device comprising: arithmetic means for computing vector information corresponding to the operating pressure of the operating section based on the output voltage from the detection circuit connected to the resistance change element. 2. The coordinate input device according to claim 1, wherein the resistance adjusting means has an output voltage obtained from a detection circuit for each pressure resistance change element as a component for the same pressure from the operating portion in all directions. A coordinate input device having means for adjusting the load resistance so that the magnitude of the vector to be applied falls within a predetermined range. 3. The coordinate input device according to claim 2, wherein the resistance adjusting means determines whether or not the magnitude of a vector whose component is the output voltage of the detection circuit when the operating portion is operated is smaller than a predetermined value. A coordinate input device having means for changing the resistance value of the load resistance in accordance with the coordinate input device. 4. The coordinate input device according to claim 1, wherein the detection circuit includes a plurality of load resistors having different resistance values, and the resistance adjusting means includes the pressure resistance change element from the plurality of load resistors. A coordinate input device having resistance switching means for selecting a load resistance to be connected to.