WO2014119490A1

WO2014119490A1 - Coordinate input device, coordinate input method, and storage medium

Info

Publication number: WO2014119490A1
Application number: PCT/JP2014/051579
Authority: WO
Inventors: 成人豊田
Original assignee: 株式会社資生堂
Priority date: 2013-01-29
Filing date: 2014-01-24
Publication date: 2014-08-07
Also published as: JP2014146198A; JP5616987B2; TW201435680A

Abstract

A coordinate input device comprises: four pressure sensors that are disposed in predetermined positions of a panel; an output ratio acquisition means that sums up output values obtained by the four pressure sensors, with respect to the respective pressure sensors, finds the ratios of the output values of the pressure sensors to the summed output values, and acquires the found ratios of the output values as individual output ratios of the respective pressure sensors; and a pressing position determination means that, using the individual output ratios of the respective pressure sensors obtained by the output ratio acquisition means and a previously acquired coordinate correction amount, determines a pressing position on the panel.

Description

Coordinate input device, coordinate input method, and storage medium

One aspect of the present disclosure relates to a coordinate input device, a coordinate input method, and a storage medium.

Conventionally, as a method for detecting a finger contact position or a pressed position of a touch panel (hereinafter referred to as “panel” as necessary) used for display means such as a smartphone, a tablet terminal, and an input / output display, electromagnetic induction or parallel A method using light blocking, a method using rigid body dynamics, and the like are known. As a method of utilizing rigid body mechanics, a member that supports a panel is provided with a sensor that detects a component force of the force applied to the panel, and the finger is applied to the panel by comparing the output values detected from each sensor. A method for identifying a contact area is known (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 61-292732

However, the method described in Patent Document 1 described above has an advantage that the structure of the sensing method is simple and does not depend on the characteristics of the panel. On the other hand, the pressed position is simply determined using the force component detected by the sensor. For this reason, there has been a problem that the pressed position on the panel cannot be detected with high accuracy.

The present invention has been made in view of the above problems, and an object thereof is to accurately determine the pressing position on the panel.

According to one aspect of the present disclosure, the four pressure sensors arranged at predetermined positions of the panel and the output values obtained by the four pressure sensors are summed, and for each of the pressure sensors, the sum of the output values with respect to the summed output values. The ratio of the output value of the pressure sensor is obtained, and the ratio of the obtained output value is acquired as an individual output ratio for each of the pressure sensors, and for each of the pressure sensors obtained by the output ratio acquisition means A coordinate input device is provided that includes a pressing position determination unit that determines a pressing position on the panel using the individual output ratio and the coordinate correction amount acquired in advance.

According to one aspect of the present disclosure, it is possible to accurately determine the pressed position on the panel.

It is a top view which shows an example of schematic structure of the coordinate input device which concerns on this embodiment. It is a side view which shows an example of schematic structure of the coordinate input device which concerns on this embodiment. It is a figure which shows an example of the function structure of PC concerning this embodiment. It is a figure which shows an example of the hardware constitutions of PC concerning this embodiment. It is a figure for demonstrating the sensor calibration of a strain gauge. It is a figure for demonstrating the sensor calibration of a strain gauge. It is a figure for demonstrating the sensor calibration of a strain gauge. It is a flowchart which shows the flow of the coordinate correction amount acquisition process which concerns on this embodiment. It is a figure explaining an example of the idea of the displacement amount acquisition type | formula which concerns on this embodiment. It is a flowchart which shows the flow of the press position determination process which concerns on this embodiment.

Hereinafter, embodiments of the present invention will be described in detail.

<Schematic diagram of coordinate input device>
1A and 1B are diagrams illustrating an example of a schematic configuration of a coordinate input device according to the present embodiment. As shown in FIG. 1A, the coordinate input device 10 is configured to include a sensor unit 20 and a PC (Personal Computer) 30.

The sensor unit 20 is configured to include a housing unit 21, a panel 22, and a strain gauge 23 as a pressure sensor.

The housing unit 21 has strain gauges 23 arranged at predetermined positions (four corners in the example of FIG. 1A). In addition, as shown in FIG. 1B, the housing portion 21 has a panel 22 disposed on a strain gauge 23.

The panel 22 is made of, for example, a silicon material, an aluminum plate, a metal synthetic plate, or the like. The panel 22 and the strain gauge 23 are connected by, for example, point contact. Note that the panel 22 includes, for example, a panel, a sheet, and the like for detecting a pressure level and a position where a pressure load is generated, and may be, for example, a touch panel as a display unit.

The strain gauge 23 is composed of, for example, a load cell, and has strain gauges 23-1 to 23-4. The strain gauges 23-1 to 23-4 are arranged on the housing portion 21 so as to support predetermined positions of the panel 22 (four corners in the example of FIG. 1A). The strain gauge 23 may incorporate an amplifier.

The sensor unit 20 converts the values obtained by the strain gauges 23-1 to 23-4 into digital values using a built-in AD converter, and transmits the converted digital values to the PC 30 via, for example, a USB cable.

In addition, about the magnitude | size, shape, etc. of the housing | casing part 21, the panel 22, the strain gauge 23, etc. in the sensor part shown to FIG. 1A and 1B, it is not limited to this, For example, the panel 22 is circular in addition to a rectangle. Or the like.

The PC 30 uses the digital value acquired from the sensor unit 20 to determine the position where the panel 22 is touched or pressed, and based on the determined position, detects a user action or the like performed on the sensor unit 20. Information processing apparatus.

Note that the PC 30 may be, for example, a PD (Portable Device), a PDA (Personal Data Assistant), a mobile phone, a game machine, or the like, or may be configured to be integrated with the sensor unit 20.

<PC30: Functional configuration example>
Next, a functional configuration of the PC 30 included in the coordinate input device 10 described above will be described. FIG. 2 is a diagram illustrating an example of a functional configuration of the PC according to the present embodiment.

As shown in FIG. 2, the coordinate input device 10 includes an input unit 31, an output unit 32, a storage unit 33, an output ratio acquisition unit 34, each side pressure acquisition unit 35, and a vertical horizontal direction pressure acquisition unit 36. A displacement amount acquisition means 37, a coordinate correction amount acquisition means 38, a pressed position determination means 39, and a control means 40.

Here, the coordinate input device 10 in the present embodiment performs two processes, a pre-process and a pressed position determination process, in short. In the pre-processing, a correction target area on a rectangle (for example, on the panel 22) formed in advance by four sides each having two strain gauges 23 as end portions of the four strain gauges 23-1 to 23-4. A coordinate correction amount (for example, a scale having a reference point of the correction target region and resolution) is acquired.

This coordinate correction amount is obtained by using, for example, the output ratio acquisition unit 34, each side pressure acquisition unit 35, the vertical and horizontal direction pressure acquisition unit 36, the displacement amount acquisition unit 37, and the coordinate correction amount acquisition unit 38. can get.

In the pressing position determination process, the pressing position is determined from the coordinate correction amount acquired in the pre-processing and the value obtained from the strain gauges 23-1 to 23-4 when the panel 22 is pressed by the user.

This pressing position is determined by using the output ratio acquisition means 34, each side pressure acquisition means 35, the vertical and horizontal direction pressure acquisition means 36, the displacement amount acquisition means 37, and the pressing position determination means 39.

The details will be described below. The input unit 31 includes, for example, a keyboard, a pointing device such as a mouse, and the like, and receives inputs such as start and end of various instructions.

The output unit 32 includes, for example, a display, a speaker, and the like, and displays the content input by the input unit 31 and the content executed based on the input content, and outputs a sound.

The storage unit 33 stores information such as an output value such as a pressing force obtained by the sensor unit 20, a coordinate correction amount acquired in advance, a value obtained by each unit, and the like.

The output ratio acquisition means 34 totals the output values of the four strain gauges 23-1 to 23-4 obtained by the sensor unit 20, and each strain gauge 23 (strain gauge 23-1 to 23-) with respect to the total output value. The ratio of the output value (1 out of 4) is obtained. Further, the output ratio acquisition unit 34 acquires the calculated ratio of output values as the individual output ratio of each strain gauge 23.

For example, in the preliminary process, the output ratio acquisition unit 34 obtains strain gauges 23-1 to 23-4 obtained by pressing predetermined positions (for example, 25 locations) set at equal intervals in the correction target area on the rectangle described above. Based on this value, the individual output ratio of each strain gauge 23 for each predetermined position is acquired. In the pressing position determination process, the individual output ratio of each strain gauge 23 at the user's pressing point is acquired based on the values of the strain gauges 23-1 to 23-4 obtained by the user's pressing.

The output ratio acquisition unit 34 can adjust the acquired maximum value and minimum value of the individual output ratio of each strain gauge 23 to be predetermined values (for example, “100”, “0”), respectively. However, the present invention is not limited to this.

Each side pressure acquisition means 35 is respectively for the total of individual output ratios of two strain gauges 23 (for example, strain gauges 23-1 and 23-2) arranged at both ends of each side of the correction target region on the rectangle described above. Using the individual output ratio of the strain gauge 23 (for example, the strain gauge 23-1 or the strain gauge 23-2), pressures relating to the respective sides (for example, the upper side, the lower side, the right side, and the left side) constituting the correction target area on the rectangle Find the percentage of each.

For example, in the pre-processing, each side pressure acquisition unit 35 may obtain the ratio of the pressure related to each side at a predetermined position on each side (for example, 16 points in contact with the outer periphery of the rectangle among the 25 points described above). . Further, in the pressing position determination process, the ratio of the pressure related to each side at the pressing position of the user is obtained based on the individual output ratio of each strain gauge 23 obtained by the pressing of the user.

The vertical / horizontal pressure acquisition means 36 uses the ratio of the pressure relating to each side of the rectangle (correction target area) obtained by each side pressure acquisition means 35 to make the rectangle (correction target area) vertical or horizontal. Each of the pressure ratios is determined.

For example, in the pre-processing, the vertical / horizontal pressure means 36 may obtain the ratio of the pressure in the vertical direction or the horizontal direction at a predetermined position (for example, 16 positions described above) on each side described above. In the pressing position determination process, the ratio of the pressure in the vertical or horizontal direction at the pressing position of the user is obtained.

The displacement amount acquisition means 37 uses the ratio of the pressure related to each side obtained by each side pressure acquisition means 35 and the ratio of the pressure related to the vertical direction or the horizontal direction obtained by the vertical horizontal direction pressure acquisition means 36. Thus, the displacement amount from each side of the rectangle (correction target area) at the pressed position is acquired.

For example, in the pre-processing, the displacement amount acquisition unit 37 calculates the ratio of the pressure related to each side at a predetermined position on each side described above (for example, 16 positions described above) and the ratio of the pressure applied in the vertical direction or the horizontal direction. It is preferable to obtain a displacement amount from each side at a predetermined position on each side. In the pressing position determination process, the displacement amount from each side at the pressing position of the user is acquired.

The coordinate correction amount acquisition unit 38 acquires the average value of the displacement amount of each side using the displacement amount from each side at a predetermined position on each side obtained by the displacement amount acquisition unit 37 in the pre-processing, for example. In addition, the coordinate correction amount acquisition unit 38 acquires a coordinate correction amount for setting the coordinates of the correction target region described above using the average value of the displacement amounts of the respective sides.

Here, for example, the average value of the displacement amount on the left side and the average value of the displacement amount on the upper side are respectively obtained as reference points of the correction target region and set as coordinate correction amounts. Further, by dividing a predetermined value (for example, “100”) by the difference between the average value of the displacement amount on the left side and the average value of the displacement amount on the right side, the resolution between the left side and the right side of the correction target region is obtained. Coordinate correction amount. Similarly, by dividing a predetermined value (for example, “100”) by the difference between the average value of the displacement amount on the upper side and the average value of the displacement amount on the lower side, the resolution between the upper side and the lower side of the correction target region To obtain the coordinate correction amount.

The coordinate correction amount acquisition unit 38 stores the coordinate correction amount obtained in this way (for example, a scale having a reference point and resolution of the correction target region) in the storage unit 33. The coordinate correction amount stored in the storage unit 33 is used in the pressing position determination process in the pressing position determination unit 39.

The pressing position determination means 39 determines the pressing position on the panel 20 using the individual output ratio of the strain gauge 23 obtained by the output ratio acquisition means 34. Specifically, the pressing position determination unit 39 includes the displacement amount from each side obtained by the displacement amount acquisition unit 37 when the panel is pressed by the user, and the coordinate correction amount obtained by the coordinate correction amount acquisition unit 38. Are used to determine the pressed position.

The control means 40 controls the entire components of the coordinate input device 10. The control means 40 is based on an instruction from the input means 31 by a user or the like, for example, an output ratio acquisition means 34, each side pressure acquisition means 35, a vertical and horizontal direction pressure acquisition means 36, a displacement amount acquisition means 37, The coordinate correction amount acquisition unit 38 and the pressed position determination unit 39 are controlled to determine the pressed position with respect to the panel 22.

<PC30: Hardware configuration example>
The PC 30 described above can be executed by generating a coordinate input program for causing a computer to execute each function or each means, and installing it on a general-purpose personal computer, for example. FIG. 3 is a diagram illustrating an example of a hardware configuration of the PC according to the present embodiment.

As shown in FIG. 3, the PC 30 includes an input device 41, an output device 42, a drive device 43, an auxiliary storage device 44, a memory device 45, a CPU (Central Processing Unit) 46, and a network connection device 47. These are connected to each other by a system bus B.

The input device 41 has a pointing device such as a keyboard and a mouse operated by a user or the like, and inputs various operation signals such as execution of a program from the user or the like.

The output device 42 has a display for displaying a GUI (Graphical User Interface), a screen, and the like necessary for operating the computer main body for performing each process of the present embodiment, and the program is executed by the control program of the CPU 46 Progress and results are displayed.

The input device 41 and the output device 42 may be integrated input / output devices such as a touch panel.

Here, the coordinate input program installed in the computer main body is provided by a portable storage medium 48 such as a USB memory or a CD-ROM, for example. The storage medium 48 can be set in the drive device 43, and a program included in the storage medium 48 is installed from the storage medium 48 to the auxiliary storage device 44 via the drive device 43.

The auxiliary storage device 44 is a storage means such as a hard disk, and stores a coordinate input program, a control program provided in the computer, etc., and performs input / output as necessary.

The memory device 45 stores a program read from the auxiliary storage device 44 by the CPU 46. The memory device 45 uses, for example, a ROM (Read Only Memory), a RAM (Random Access Memory), or the like.

The CPU 46 controls processing of the entire computer such as various operations and data input / output with each hardware component based on a control program such as an OS (Operating System) and a program stored in the memory device 45. Various information during the execution of the program is acquired from the auxiliary storage device 44, and the execution result and the like are stored.

The network connection device 47 obtains a program from another device connected to the communication network by connecting to the communication network or the like, and provides the execution result obtained by executing the program to the other device. To do.

The PC 30 can execute each process according to the present embodiment by having the above-described hardware configuration.

<Sensor calibration (pre-processing)>
Next, sensor calibration of the strain gauges 23-1 to 23-4 will be described. 4A to 4C are diagrams for explaining sensor calibration of a strain gauge.

As shown in FIG. 4A, each of the four strain gauges 23-1 to 23-4 has a rectangle formed by four sides having two strain gauges 23 as end portions, and the formed rectangular region (that is, a correction target) A rectangular panel 22 is provided corresponding to the region.

In the example of FIG. 4A, the strain gauges 23 are disposed at the end portions of the panel 22, and the sides having the two strain gauges 23 as the end portions correspond to the sides of the panel 22. Therefore, in the example of FIG. 4A, when a predetermined portion on the panel 22 in this rectangular area is pressed, the coordinates on the panel 22 can be acquired. In the present embodiment, the present invention is not limited to this, and the shape of the rectangular area may not correspond to the shape of the panel 22.

In the pre-processing, the rectangular area (that is, the panel 22) is divided at predetermined positions set at equal intervals in advance (in the example of FIG. 4A, 25 corners of the grid), and coordinate values corresponding to the divided positions are obtained. It is assumed that it is set. That is, the example of FIG. 4A shows an example in which the rectangular area (that is, the panel 22) is divided into 16, and (x, y) = (0, 0) to (4, 4), for example, are set as the coordinate points. Has been.

The output ratio acquisition means 34 is obtained from the strain gauges 23-1 to 23-4 in a state where nothing is placed on the panel 22 (for example, 0 g) at a predetermined timing, for example, at the time of shipment or an instruction from the user. An output value (zero value data a _{0, n} ) is acquired (n: number 1, 2, 3, 4 of strain gauge 23).

Next, as shown in FIG. 4B, the output ratio acquisition means 34 is predetermined on the coordinate points set at the above-described equal intervals on the panel 22 (25 corners in the above-described square in the example of FIG. 4B). The output value c _{cal, n} (x, y) obtained from the strain gauges 23-1 to 23-4 is obtained (x = 0, 1, 2, 3) with a weight of 100 g (for example, 100 g) placed thereon. , 4, y = 0, 1, 2, 3, 4).

Next, the output ratio acquisition unit 34 subtracts the zero value data a _{0, n} from the output value c _{cal, n} (x, y) in a state where a predetermined weight is placed, and outputs an output value d _{cal, n} (x, y) is acquired. The output value d _{cal, n} (x, y) after zero value correction is obtained using the following equation (1).

Next, the output ratio acquisition means 34 sums up the output values d _{cal, n} (x, y) obtained by correcting the zero values of the strain gauges 23-1 to 23-4 at the coordinate points set as described above. Thus, the total output value D _{cal, n} (x, y) is obtained using the following equation (2).

The total output value _{D cal,} n (x, y) strain gauges 23-1 to 23-4 each output value _{d cal} for, n (x, y) ratio _{e cal} of, n and (x, y) below It acquires using Formula (3) of these.

As described above, the output ratio acquisition unit 34 calculates the ratio e _{cal, n} (x, y) of the output values of the strain gauges 23-1 to 23-4 at each set coordinate point to the strain gauge at each coordinate point. Obtained as individual output ratios e _{cal, n} (x, y) of 23-1 to 23-4.

The output ratio acquisition means 34 determines that the difference between the maximum value and the minimum value of the individual output ratios e _{cal, n} (x, y) of the strain gauges 23-1 to 23-4 is a predetermined value (eg, “100”). ), The calibration value Val _{cal, n} (x, y) may be obtained using the following equation (4).

Further, the output ratio acquisition means 34 uses the calibration value Val _{cal, n} (x, y), and the maximum value of the individual output ratios e _{cal, n} (x, y) of the strain gauges 23-1 to 23-4. And calibrated values f _{cal, n} (x, y) are obtained by using the following equation (5) so that the minimum value and the minimum value become predetermined values (for example, “100”, “0”).

As described above, as pre-processing, sensor calibration of the strain gauges 23-1 to 23-4 is performed in advance, and the calibrated values f _{cal, n} (x, y) of the strain gauges 23-1 to 23-4 are used. Thus, a coordinate correction amount for setting the coordinates of the rectangular area (correction target area) may be obtained.

In the following description, as shown in FIG. 4C, the side with the strain gauges 23-1 and 23-2 as the end is the left side, and the side with the strain gauges 23-2 and 23-3 as the end is the lower side. And Further, the side having the strain gauges 23-3 and 23-4 as the end portion is the right side, and the side having the strain gauges 23-4 and 23-1 as the side is the top side. A description will be given using an example in which the panel 22 is arranged in a rectangular area (that is, a correction target area).

<Flow of coordinate correction amount acquisition processing>
Next, a coordinate correction amount acquisition process for setting the coordinates of the panel 22 (that is, the correction target area) executed in the above-described pre-process will be described. FIG. 5 is a flowchart showing the flow of coordinate correction amount acquisition processing according to the present embodiment.

As shown in FIG. 5, the output ratio acquisition means 34 first performs the above-described sensor calibration at a predetermined timing such as at the time of shipment or an instruction from the user.

Specifically, the output ratio acquisition means 34 acquires the zero value data a _{0, n} from the strain gauges 23-1 to 23-4 (S10), and each coordinate point set at equal intervals on the panel 22 (S10). 4A to 4C, an output value c _{cal, n} (x, y) when a predetermined weight (for example, 100 g) is placed on the above-mentioned square corners 25) is acquired (S11), and each coordinate is obtained. An output value d _{cal, n} (x, y) obtained by correcting the zero value at the point is acquired (S12).

Further, when the output ratio acquisition means 34 acquires the total output value D _{cal, n} (x, y) at each coordinate point, the strain gauge 23− for the total output value D _{cal, n} (x, y) at each coordinate point. The individual output ratio e _{cal, n} (x, y) _, which is the ratio of the output values d _{cal, n} (x, y) of 1 to 23-4 is acquired (S13).

Next, the output ratio acquisition means 34 obtains the maximum value and the minimum value among the individual output ratios e _{cal, n} (x, y) of the strain gauges 23-1 to 23-4, and calculates the maximum value and the minimum value. A calibration value Val _{cal, n} for the difference to be a predetermined value (for example, “100”) is obtained (S14).

Next, the output ratio acquisition unit 34 sets the individual output ratios e of the strain gauges 23-1 to 23-4 so that the maximum value and the minimum value become predetermined values (for example, “100”, “0”), respectively. _{cal, n} (x, y) is calibrated using the calibration value Val _{cal, n} (x, y), and a calibrated value f _{cal, n} (x, y) is obtained (S15).

Next, each side pressure acquisition means 35, for example, the ratio U _cal (x, y) of the pressure related to each side at a predetermined position of each side (for example, 16 positions in contact with the outer periphery of the panel 22 among the 25 positions described above). ), B _cal (x, y), L _cal (x, y), and R _cal (x, y) are obtained (S16). For example, each side pressure acquisition means 35 acquires the ratio of the pressure concerning each side using the following formula (6).

For example, when calculating the ratio of the upper side at the coordinates (0, 0), each side pressure acquisition means 35 uses U _cal (0,0) = f _{cal, 4} (0,0) / (f _{cal, 1} (0,0) + f _{cal, 4} (0,0)) is used. Similarly, the ratio of the pressure related to the lower side, the left side, and the right side at the coordinates (0, 0) is also obtained.

Next, the vertical and horizontal direction pressure acquisition means 36 uses the ratio of the pressure relating to each side when the above-mentioned predetermined position is pressed, and touches the outer periphery of the panel 22 among the predetermined positions (for example, 25 locations). The pressure ratio V _cal (x, y) in the vertical direction when pressing the position) or the pressure ratio H _cal (x, y) in the horizontal direction is determined (S17).

For example, the vertical / horizontal pressure acquisition unit 36 uses the following equation (7) for the pressure ratio V _cal (x, y) in the vertical direction or the pressure ratio H _cal (x, y) in the horizontal direction. Get.

Next, the displacement amount acquiring unit 37 uses the pressure ratio V _cal (x, y) in the vertical direction or the pressure ratio H _cal (x, y) in the horizontal direction to set the predetermined position (for example, 25 Displacement amounts WX _cal (x, y) and WY _cal (x, y) from the respective sides at 16 locations in contact with the outer periphery of the panel 22 are acquired using the following equation (8) (S18). ).

Next, the average value of the displacement amount of each side is acquired using the following equation (9) (S19).

Here, for example, in the case of the left side, for example, the average of the amount of displacement on the left side is calculated from the amount of displacement at each coordinate point (0, 1), (0, 2), (0, 3), (0, 4) on the left side. (Lcx = average (WX _cal (0, y)) Similarly, the average value of the displacement amounts of the right side, the upper side, and the lower side is obtained from the displacement amounts of the coordinate points of the right side, the upper side, and the lower side.

Next, the coordinate correction amount acquisition means 38 acquires a coordinate correction amount for setting the coordinates of the rectangular area (that is, the correction target area) described above (S20).

Here, for example, the coordinate correction amount acquisition unit 38 sets the average value Lcx of the displacement amount on the left side as the reference point calXval and the average value Ucy of the displacement amount on the upper side as the reference point calYval. Further, the coordinate correction amount acquisition unit 38 uses the difference between the average value Lcx of the displacement amount on the left side and the average value Rcx of the displacement amount on the right side to obtain a resolution calXscale where the difference becomes a predetermined value (for example, “100”). get. Similarly, using the difference between the average value Ucy of the displacement amount on the upper side and the average value Bcy of the displacement amount on the lower side, a resolution calYscale where the difference becomes a predetermined value (for example, “100”) is acquired.

The displacement amount determination unit 37 acquires the above-described coordinate correction amounts (reference points calXval, calXval, resolution calXscale, calYscale) using, for example, the following equation (10).

As described above, in the present embodiment, a coordinate correction amount for setting the coordinates of the correction target region is acquired in advance processing. The acquired coordinate correction amount is stored in the storage means 33, for example, and used in the pressed position determination process. In the present embodiment, an example of acquiring the coordinate correction amount is not limited to this.

<Displacement acquisition formula>
Next, Expression (8) used when acquiring the above-described displacement amount will be described. FIG. 6 is a diagram for explaining an example of a concept of an expression used for obtaining the displacement amount.

As shown in FIG. 6, a method for obtaining the displacement amount WX (that is, the X coordinate) from each side at the pressed position when an arbitrary position (for example, the pressed position A) of the panel 22 is pressed will be described. Here, for example, the ratio of the load ratio in the X direction (lateral direction) of the upper side and the lower side is taken into account.

As mentioned above, the ratio of pressure on the upper side is
U _cal = f _{cal, 4} / (f _{cal, 1} + f _{cal, 4} )
And the ratio of the pressure on the lower side,
B _cal = f _{cal, 3} / (f _{cal, 2} + f _{cal, 3} )
It shall be expressed as

Here, for example, the ratio of the weight of the upper side to the whole and the ratio of the weight of the lower side to the whole are respectively expressed as follows.

For example, the ratio of the weight of the upper side to the whole
V _cal = f _{cal, 1} + f _{cal, 4} / (f _{cal, 1} + f _{cal, 2} + f _{cal, 3} + f _{cal, 4} )
And If the sum of the weight ratio of the upper side and the lower side is “1”, the weight ratio of the lower side is
1-V _cal = f _{cal, 2 +} f _{cal, 3} / (f _{cal, 1} + f _{cal, 2} + f _{cal, 3} + f _{cal, 4} )
Can be expressed as Note that V _cal is an expression similar to that described as the ratio of the pressure in the vertical direction described above.

Here, when the pressing position A is pressed, the pressure related to the upper side point P (U _cal , 0) is set as f _{cal, 1} + f _{cal, 4,} and the pressure related to the lower side point Q (B _cal , 0) is set as , F _{cal, 2} + f _{cal, 3} .

The X coordinate of the center of gravity of the point P and the point Q (that is, the x coordinate of WX) can be expressed as follows. For example, if there are masses m and n, and the coordinates of the mass points a and b are (Xa, Ya) and (Xb, Yb), respectively, an equation for obtaining the coordinates (X, Y) of the center of gravity of the mass points a and b (ie, mass) m = mass point a and mass n = mass point b), for example, X = (n × Xa + m × Xb) / (m + n), Y = (n × Ya + m × Yb) / (m + n) ,
WX (x) = (U _cal × (f _{cal, 2} + f _{cal, 3} ) + B _cal × (f _{cal, 1} + f _{cal, 4} ) / (f _{cal, 2} + f _{cal, 3} + f _{cal, 1} + f _{cal, 4} )
= (U _cal × (f _{cal, 2} + f _{cal, 3} ) / (f _{cal, 2} + f _{cal, 3} + f _{cal, 1} + f _{cal, 4} ) + B _cal × (f _{cal, 1} + f _{cal, 4} ) / (f _{cal, 2} + f _{cal, 3} + f _{cal, 1} + f _{cal, 4} )
= (U _cal × (1−V _cal ) + B _cal × V _cal ) (11)
Similarly, the y-coordinate of WX when the pressing position A is pressed can be expressed as follows.

WX (y) = (0 × (f _{cal, 2} + f _{cal, 3} ) + 1 × (f _{cal, 1} + f _{cal, 4} ) / (f _{cal, 2} + f _{cal, 3} + f _{cal, 1} + f _{cal, 4} )
= F _{cal, 1} + f _{cal, 4} / (f _{cal, 2} + f _{cal, 3} + f _{cal, 1} + f _{cal, 4} )
= V _cal
From the above-described WX (x) and WX (y), WX (x, y) can be expressed as follows.

WX (x, y) = (U _cal × (1−V _cal ) + B _cal × V _cal , V _cal )
Therefore, the X coordinate of the pressing position A, taking into account the horizontal weight ratios of the upper side and the lower side, can be expressed as U _cal × (1−V _cal ) + B _cal × V _cal .

Further, a method for obtaining the displacement amount WY (that is, the Y coordinate) from each side at the pressing position A when the pressing position A is pressed will be described. Here, for example, the ratio of the load ratio in the Y direction (vertical direction) of the right side and the left side is taken into account.

As described above, the ratio of the pressure on the left side is
L _cal = f _{cal, 2} / (f _{cal, 1} + f _{cal, 2} )
And the ratio of pressure on the right side,
R _cal = f _{cal, 3} / (f _{cal, 3} + f _{cal, 4} )
It shall be expressed as

Here, for example, the ratio of the weight of the left side to the whole and the ratio of the weight of the right side to the whole are respectively expressed as follows.

For example, the ratio of the weight of the left side to the whole
H _cal = f _cal , ₁ + f _{cal, 2} / (f _{cal, 1} + f _{cal, 2} + f _{cal, 3} + f _{cal, 4} )
And If the total weight ratio of the left and right sides is “1”, the weight ratio of the right side is
1-H _cal = f _{cal, 3 +} f _{cal, 4} / (f _{cal, 1} + f _{cal, 2} + f _{cal, 3} + f _{cal, 4} )
Can be expressed as H _cal is an expression similar to that described as the ratio of the pressure in the horizontal direction described above.

Here, the pressure related to the point P ′ (0, L _cal ) on the left side when the pressing position A is pressed is set to f _{cal, 1} + f _{cal, 4,} and the pressure related to the point Q ′ (1, R _cal ) on the right side. _Is f _{cal, 3} + f _{cal, 4} .

The Y-coordinate of the center of gravity between the point P ′ and the point Q ′ (that is, the y-coordinate of WY) is expressed as follows by using an internal dividing formula that internally divides the mass point a of the mass m and the mass point b of the mass n. Can be expressed as

WY (y) = (L _cal × (f _{cal, 3} + f _{cal, 4} ) + R _cal × (f _{cal, 1} + f _{cal, 2} ) / (f _{cal, 3} + f _{cal, 4} + f _{cal, 1} + f _{cal, 2} )
= (L _cal × (f _{cal, 3} + f _{cal, 4} ) / (f _{cal, 3} + f _{cal, 4} + f _{cal, 1} + f _{cal, 2} ) + R _cal × (f _{cal, 1} + f _{cal, 2} ) / (f _{cal, 3} + _{fcal, 4} + _{fcal, 1} + _{fcal, 2} )
= L _cal × (1-H _cal ) + R _cal × H _cal )
Similarly, the x coordinate of the displacement amount WY of pressing the pressing position A can be expressed as follows.

WY (x) = (0 × (f _{cal, 3} + f _{cal, 4} ) + 1 × (f _{cal, 1} + f _{cal, 2} ) / (f _{cal, 3} + f _{cal, 4} + f _{cal, 1} + f _{cal, 2} )
= F _{cal, 1} + f _{cal, 2} / (f _{cal, 3} + f _{cal, 4} + f _{cal, 1} + f _{cal, 2} )
= H _cal
From the above-described WY (x) and WY (y), WY (x, y) can be expressed as follows.

WY (x, y) = (H _cal , L _cal × (1−H _cal ) + R _cal × H _cal )
Therefore, the Y coordinate of the pressing position A, taking into account the weighting ratios in the vertical direction of the left side and the right side, can be expressed as L _cal × (1−H _cal ) + R _cal × H _cal .

In addition, you may obtain | require WX and WY mentioned above as follows.

For example, in the case of WX, the left end of the upper side shown in FIG. 6 is coordinates (x1, y1), the left end of the lower side is coordinates (x1, y1 + 1), the right end of the upper side is coordinates (x4, y4), and the right end of the lower side is coordinates (x4). , Y4 + 1).

Here, the coordinates of the point P described above are (Px, Py), and the ratio of the pressure from the upper side coordinates (x1, y1) to the point P is f _{cal, 1} / (f _{cal, 1} + f _{cal, 4} ). The ratio of the pressure from the point P to the upper side coordinates (x4, y4) is f _{cal, 4} / (f _{cal, 1} + f _{cal, 4} ).

Further, the coordinates of the point Q described above are (Qx, Qy), the ratio of the pressure from the lower side coordinates (x1, y1 + 1) to the point Q is f _{cal, 2} / (f _{cal, 2} + f _{cal, 3} ), The ratio of the pressure from the point Q to the lower side coordinate (x4, y4 + 1) is defined as f _{cal, 4} / (f _{cal, 2} + f _{cal, 3} ).

At this time, Px and Qx can be expressed as follows.

Px = x1 + (x4−x1) × f _{cal, 1} / (f _{cal, 1} + f _{cal, 4} )
Qx = x1 + (x4−x1) × f _{cal, 2} / (f _{cal, 2} + f _{cal, 3} )
Therefore, WX can be expressed as:

WX = Px × (f _{cal, 2} + f _{cal, 3} ) / (f _{cal, 1} + f _{cal, 2} + f _{cal, 3} + f _{cal, 4} ) + Qx × (f _{cal, 1} + f _{cal, 4} ) / (f _{cal, 1} + f _{cal, 2} + f _{cal, 3} + f _{cal, 4} )
= Px × (1−V) + Qx × V (12)
Since the above equation (12) has the same meaning as the above equation (11), it is also possible to obtain WX by the method described above. Also, the case of WY can be obtained by the same method as the case of WX described above.

<Another example explaining the displacement acquisition formula>
Furthermore, Expression (8) used when acquiring the above-described displacement amount will be described by another method. For example, in the example of FIG. 6, the left side to the point P is P (x), the left side to the point Q is Q (x), and the left side to the pressed position A is X (x).

Also, let a (x) be the point from the point where a line perpendicular to the lower side from the point P and a line passing through the pressing position A from the left side and perpendicular to the right side to the pressing position A. Further, b (x) is defined as a point that intersects the lower side when passing through the pressing position A from the upper side and descending vertically to the lower side and the point Q.

At this time, the X coordinate of the pressing position A can be expressed by the following method.

If a (x): V = b (x) :( 1-V),
a (x) × (1−V) = b (x) × V
= (Q (x) −P (x) −a (x)) × V
= Q (x) × VP (x) × Va (x) × V
a (x) × (1−V) + a (x) × V = Q (x) × V−P (x) × V
a (x) − (a (x) × V) + (a (x) × V) = Q (x) × V−P (x) × V
a (x) = Q (x) × VP (x) × V
That is, X (x) = P (x) + a (x)
= P (x) -P (x) * V + Q (x) * V
= P (x) × (1-V) + Q (x) × V
Or, a (x): V = (a (x) + b (x)): 1
a (x) = (a (x) × V) + (b (x) × V)
a (x) − (a (x) × V) = b (x) × V
= (Q (x) −P (x) −a (x)) × V
= Q (x) x VP (x) x V
That is, X (x) = P (x) + a (x)
= P (x) -P (x) * V + Q (x) * V
= P (x) × (1−V) + Q (x) × V (13)
It becomes.

Since the above-described equation (13) has the same meaning as the above-described equations (11) and (12), it can be obtained as WX by the above-described method. Also, the case of WY can be obtained by the same method as the case of WX described above.

In the present embodiment, the pressing position can be determined by obtaining the displacement amounts WX and WY from each side at the pressing position when pressed by the user, for example, using the above-described equation for obtaining the displacement amount. It becomes.

<Pressing position determination process flow>
Next, a pressing position determination process when the above-described panel 22 (that is, the correction target area) is pressed by the user will be described. FIG. 7 is a flowchart showing the flow of the pressed position determination process according to the present embodiment. The processing from S21 to S26 in FIG. 7 is executed by the method used in the processing from S12 to S13 and S15 to S18 in FIG.

The processing in FIG. 5 is performed when a predetermined position is pressed by placing predetermined weights at predetermined positions on the rectangle (for example, 25 places divided at equal intervals) in order to set coordinates on the rectangle. While the amount of displacement is obtained, the processing of FIG. 7 differs in that the amount of displacement is obtained based on output values obtained from the four strain gauges 23-1 to 23-4 when the user presses.

As shown in FIG. 7, when a user's press is detected during actual measurement, the output ratio acquisition means 34 acquires the output values of the strain gauges 23-1 to 23-4 in the process of S10 of FIG. The zero value data a is subtracted to obtain the zero value corrected output value d _cal (S21).

Next, the output ratio acquisition means 24 obtains the total output value D _cal from the four output values d _cal acquired in the process of S21, and outputs each of the strain gauges 23-1 to 23-4 with respect to the total output value D _cal . An individual output ratio e _cal which is a ratio of values is acquired (S22).

Next, the output ratio acquisition means 34 obtains the maximum value and the minimum value among the individual output ratios e _cal of the strain gauges 23-1 to 23-4, and the maximum value and the minimum value are set to respective predetermined values (for example, (100), “0”) is calibrated using the calibration value Val _cal obtained by the process of S14 of FIG. 5 described above, and a calibrated value f _cal is obtained (S23).

Next, each side pressure acquisition means 35 obtains the pressure ratios U _cal , B _cal , L _cal , and R _cal related to each side using the four calibration values Val _cal acquired in the process of S23 (S24). .

Next, the vertical / horizontal pressure acquisition unit 36 obtains the pressure ratio V _{cal in} the vertical direction or the pressure ratio H _cal in the horizontal direction (S25).

Next, displacement amounts WX _cal and WY _cal from each side are obtained by the displacement amount obtaining unit 37 (S26).

Next, the pressing position determination unit 39 uses the coordinate correction amounts (for example, the reference points calXval, calXval, resolution calXscale, calYscale) acquired in advance in the process of FIG. 5 to determine the displacement from each side acquired in the process of S26. The amounts WX _cal and WY _cal are calibrated to obtain calibration values Xp and Yp (S27). The pressing position determination unit 39 may acquire the calibration values Xp and Yp using, for example, the following formula (14).

Next, the pressing position determination means 39 uses the difference from a predetermined value (for example, “50” when the diagonal line is divided into 100) in order to set the calibration values Xp and Yp as displacements from the center coordinates of the panel 22. The position offset values calXposOffset and calYposOffset are obtained (S28).

Note that the pressed position determination unit 39 may acquire, for example, the position offset values calXposOffset and calYposOffset using the following equation (15).

Next, by adding the position offset values calXposOffset and calYposOffset, the coordinates Xpos and Ypos as the pressed positions are acquired (S29). Note that the pressed position determination means 39 may determine the coordinates Xpos and Ypos by the following equation (16).

As described above, it is preferable to determine the pressing position on the panel 22 pressed by the user at the time of measurement using the coordinate correction amount for setting the coordinates obtained by sensor calibration at the time of shipment in advance.

As described above, according to the present embodiment, it is possible to accurately detect the pressed position on the panel.

The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments according to the present invention, and various modifications may be made within the scope of the gist of the present invention described in the claims. Can be changed.

This application claims priority based on Japanese Patent Application No. 2013-014820 filed on January 29, 2013, and is incorporated herein by reference in its entirety.

DESCRIPTION OF SYMBOLS 10 Coordinate input device 20 Sensor part 21 Case part 22 Panel 23 Strain gauge 30 PC
31 Input means 32 Output means 33 Storage means 34 Output ratio acquisition means 35 Each side pressure acquisition means 36 Vertical horizontal direction pressure acquisition means 37 Displacement amount acquisition means 38 Coordinate correction amount acquisition means 39 Pressed position determination means 40 Control means 41 Input device 42 Output device 43 Drive device 44 Auxiliary storage device 45 Memory device 46 CPU
47 Network connection device 48 Storage medium

Claims

Four pressure sensors arranged at predetermined positions on the panel;
The output values obtained by the four pressure sensors are summed, and the ratio of the output value of the pressure sensor to the summed output value is obtained for each pressure sensor, and the ratio of the obtained output value is determined for each pressure sensor. Output ratio acquisition means for acquiring as an individual output ratio,
Coordinates having pressing position determination means for determining a pressing position with respect to the panel using the individual output ratio for each of the pressure sensors obtained by the output ratio acquisition means and the coordinate correction amount acquired in advance. Input device.
The two pressures with respect to the total of the individual output ratios of the two pressure sensors, each of which forms a rectangle with four sides having the two pressure sensors as ends in the four pressure sensors. The coordinate input device according to claim 1, further comprising each side pressure acquisition unit that obtains a ratio of a pressure related to each side of the rectangle using an individual output ratio of each sensor.
Using the ratios of pressures related to the upper and lower sides of the rectangle or the left and right sides of the rectangle obtained by the respective side pressure acquisition means, the verticals for determining the ratios of pressures related to the vertical direction or the horizontal direction of the rectangles, respectively. The coordinate input device according to claim 2, further comprising a horizontal pressure acquisition unit.
The amount of displacement of the pressing position from each side is acquired using the ratio of pressure related to each side and the ratio of pressure related to the vertical direction or horizontal direction obtained by the vertical and horizontal direction pressure acquisition means. The coordinate input device according to claim 3, further comprising a displacement amount acquisition unit.
A coordinate correction amount for setting coordinates on the rectangle using an average value of displacement amounts from the sides at a plurality of preset pressing positions obtained on the sides obtained by the displacement amount acquisition unit. 5. The coordinate input device according to claim 4, further comprising coordinate correction amount acquisition means for acquiring.
The pressing position determining means includes
The pressing position when the panel is pressed using the displacement amount from each side of the pressing position obtained by the displacement amount obtaining unit and the coordinate correction amount obtained by the coordinate correction amount obtaining unit. The coordinate input device according to claim 5, wherein the coordinate input device is determined.
The output ratio acquisition means includes
The coordinate input device according to claim 1, wherein the individual output ratio is adjusted so that a maximum value or a minimum value of the individual output ratio of the pressure sensor becomes a predetermined value.
A coordinate input method executed by a computer,
The output values obtained by the four pressure sensors arranged at predetermined positions on the panel are summed up, and for each of the pressure sensors, the ratio of the output value of the pressure sensor to the summed output value is obtained, respectively. An output ratio acquisition procedure for acquiring a ratio as an individual output ratio for each pressure sensor;
Coordinates having a pressing position determination procedure for determining a pressing position with respect to the panel using an individual output ratio for each of the pressure sensors obtained by the output ratio acquisition procedure and a coordinate correction amount acquired in advance. input method.
The two pressures with respect to the total of the individual output ratios of the two pressure sensors, each of which forms a rectangle with four sides having the two pressure sensors as ends in the four pressure sensors. The coordinate input method according to claim 8, further comprising a side pressure acquisition procedure for respectively obtaining a pressure ratio for each side of the rectangle by using an individual output ratio of each sensor.
Using the ratios of pressures related to the upper and lower sides of the rectangle or the left and right sides of the rectangle obtained by the respective side pressure acquisition procedures, the vertical ratios for obtaining the vertical and horizontal ratios of the rectangles are obtained. The coordinate input method according to claim 9, further comprising a horizontal pressure acquisition procedure.
The amount of displacement of the pressing position from each side is acquired using the ratio of pressure related to each side and the ratio of pressure related to the vertical direction or horizontal direction obtained by the vertical and horizontal direction pressure acquisition procedure. The coordinate input method according to claim 10, further comprising a displacement amount acquisition procedure.
Coordinate correction for acquiring a coordinate correction amount for setting coordinates on the rectangle using an average value of displacement amounts at a plurality of preset pressing positions on each side obtained by the displacement amount acquisition procedure. The coordinate input method according to claim 11, further comprising a quantity acquisition procedure.
The pressing position determination procedure includes:
Using the displacement amount from each side of the pressing position obtained by the displacement amount acquisition procedure and the coordinate correction amount obtained by the coordinate correction amount acquisition procedure, the pressing position when pressing the panel The coordinate input method according to claim 12, wherein the determination is performed.
The output ratio acquisition procedure is:
The coordinate input method according to claim 8, wherein the individual output ratio is adjusted so that a maximum value or a minimum value of the individual output ratio of the pressure sensor becomes a predetermined value.
A computer-readable storage medium storing a program for causing a computer to execute a coordinate input method, wherein the coordinate input method includes:
The output values obtained by the four pressure sensors arranged at predetermined positions on the panel are summed up, and for each of the pressure sensors, the ratio of the output value of the pressure sensor to the summed output value is obtained, respectively. An output ratio acquisition procedure for acquiring a ratio as an individual output ratio for each pressure sensor;
And a pressing position determination procedure for determining a pressing position with respect to the panel using the individual output ratio for each of the pressure sensors obtained by the output ratio acquisition procedure and the coordinate correction amount acquired in advance. Medium.
In the coordinate input method, each of the four pressure sensors forms a rectangle with four sides having two pressure sensors as end portions, and the individual output ratios of the two pressure sensors arranged at both ends of each side. The storage medium according to claim 15, further comprising a side pressure acquisition procedure for respectively obtaining a ratio of pressure related to each side of the rectangle by using an individual output ratio of each of the two pressure sensors with respect to the total.
The coordinate input method uses the ratio of the pressure related to the upper and lower sides of the rectangle or the left and right sides of the rectangle obtained by the respective side pressure acquisition procedure, and the pressure related to the vertical or horizontal direction of the rectangle. The storage medium according to claim 16, further comprising a vertical and horizontal direction pressure acquisition procedure for obtaining the ratio of each of the ratios.
The coordinate input method uses the ratio of the pressure related to each side and the ratio of the pressure related to the vertical direction or the horizontal direction obtained by the vertical and horizontal direction pressure acquisition procedure, from each side of the pressing position. The storage medium according to claim 17, further comprising a displacement amount acquisition procedure for acquiring a displacement amount.
The coordinate input method uses coordinate correction for setting coordinates on the rectangle using an average value of displacement amounts at a plurality of preset pressing positions on the sides obtained by the displacement amount acquisition procedure. The storage medium according to claim 18, further comprising a coordinate correction amount acquisition procedure for acquiring the amount.
The pressing position determination procedure includes:
Using the displacement amount from each side of the pressing position obtained by the displacement amount acquisition procedure and the coordinate correction amount obtained by the coordinate correction amount acquisition procedure, the pressing position when pressing the panel The storage medium according to claim 19, wherein the storage medium is determined.
The output ratio acquisition procedure is:
The storage medium according to claim 15, wherein the individual output ratio is adjusted so that a maximum value or a minimum value of the individual output ratio of the pressure sensor becomes a predetermined value.