Operation detection device

Abstract

To provide an operation detection device configured to suppress the variance of coordinates.SOLUTION: An operation detection device 1 includes, as shown in Fig. 1(a) to Fig. 2: a detection unit 3 which detects a touch operation for touching an operation surface 20 to output a detection value S based on a capacitance that increases from before the touch operation; and a control unit 4 serving as a determination unit, which has a determination threshold value Th to determine the start of the touch operation, determines the start of the touch operation when the detection value S becomes equal to or larger than the determination threshold value Th, and determines the end of the touch operation when a first condition based on a maximum detection value Smax after the touch start determination is satisfied.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an operation detection device. [Background technology]

[0002] As a conventional technique, an information input device is known that includes a plurality of electrode wires arranged in the X-axis and Y-axis directions and a first detection means that detects a change in capacitance due to an operator's finger approaching the electrode wires (see, for example, Patent Document 1).

[0003] This information input device detects the XY coordinates of the touch position of the fingertip and outputs the coordinate data to a computer or the like. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 7-129321 Summary of the Invention [Problem to be solved by the invention]

[0005] In such conventional information input devices, the change in capacitance due to a finger approaching depends on the size and shape of the finger. Therefore, if the sensitivity is increased for fingers that cause small capacitance changes, the sensitivity may be too high for fingers that cause large capacitance changes, and the device may detect the fingers even when the fingers are floating, which may result in the coordinates of the detected operation being distorted and reduced operability.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide an operation detection device capable of suppressing deviation of coordinates. [Means for solving the problem]

[0007] One aspect of the present invention provides an operation detection device that includes a detection unit that detects a touch operation on an operation surface and outputs a detection value based on electrostatic capacitance that increases from before the touch operation, and a judgment unit that has a judgment threshold for determining the start of the touch operation, and determines the start of the touch operation when the detection value becomes equal to or greater than the judgment threshold, and determines the end of the touch operation when a first condition based on a maximum detection value after the judgment is satisfied. Effect of the Invention

[0008] According to the present invention, it is possible to suppress deviation of coordinates. [Brief description of the drawings]

[0009] [Figure 1] 1(a) and 1(b) are diagrams for explaining an example of a state of an operating finger with respect to an operating surface of an operation detection device according to an embodiment, and FIG. 1(c) is an example of a block diagram of the operation detection device. [Diagram 2] FIG. 2 is a diagram for explaining an example of a determination in the embodiment and a determination in a comparative example. [Diagram 3] FIG. 3 is a flowchart illustrating an example of the operation of the operation detection device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] (Summary of the embodiment) The operation detection device according to the embodiment is generally configured to include a detection unit that detects a touch operation on an operation surface and outputs a detection value based on capacitance that increases from before the touch operation, and a judgment unit that has a judgment threshold for determining the start of the touch operation, and that determines the start of the touch operation when the detection value becomes equal to or greater than the judgment threshold, and determines the end of the touch operation when a first condition based on a maximum detection value after the judgment is satisfied.

[0011] This operation detection device determines the end of a touch operation based on a first condition according to the maximum detection value, not a fixed threshold value. Therefore, the operation detection device is less likely to determine the start and end of a touch operation depending on the size, shape, and other properties of the detection target, and is able to properly detect a touch operation by suppressing erroneous determination that a state in which the detection target is floating above the operation surface is a touch operation. Therefore, the operation detection device is able to suppress deviation of coordinates.

[0012] [Embodiment Mode] (Overview of operation detection device 1) FIG. 1(a) is a diagram showing an example of a state where an operating finger is in contact with an operating surface, FIG. 1(b) is a diagram showing an example of a state where an operating finger is separated from the operating surface, and FIG. 1(c) is an example of a block diagram of an operation detection device. FIG. 2 is a diagram for explaining an example of a judgment in the embodiment and a judgment in the comparative example. The upper part of FIG. 2 is a diagram showing an example of a time change of a detection value S of a certain coordinate with a detection value S of the certain coordinate as a vertical axis and a time t as a horizontal axis. The upper center part of FIG. 2 is a diagram for explaining an example of a judgment of a start (ON) and an end (OFF) of a touch operation according to the comparative example, and the lower center part is a diagram for explaining an example of permission and prohibition of updating of coordinates according to the comparative example. The upper lower part of FIG. 2 is a diagram for explaining an example of a judgment of a start (ON) and an end (OFF) of a touch operation according to the embodiment, and the lower lower part is a diagram for explaining an example of permission and prohibition of updating of coordinates according to the embodiment.

[0013] In the drawings relating to the embodiments described below, the ratios and shapes of figures may differ from the actual ratios and shapes. In Fig. 1(c), arrows indicate the flow of main signals and information.

[0014] The operation detection device 1 according to the present embodiment is mounted on a vehicle, for example, and operates an in-vehicle device of the vehicle. For example, the operation detection device 1 is used as a touch panel of a center display or a touch pad arranged on a steering wheel.

[0015] As shown in FIG. 1(a) to FIG. 2, the operation detection device 1 has a detection unit 3 that detects a touch operation on an operation surface 20 and outputs a detection value S based on a capacitance that increases from before the touch operation, and a judgment threshold value Th that judges the start of a touch operation. When the detection value S becomes equal to or greater than the judgment threshold value Th, the operation detection device 1 judges the start of a touch operation and outputs a maximum detection value S after the judgment. max and a control unit 4 serving as a determination unit that determines the end of the touch operation when a first condition based on the above is satisfied.

[0016] The control unit 4 also determines the minimum detection value S after the end of the touch operation. min If a second condition based on the above is satisfied, it is determined that a touch operation subsequent to the touch operation has been performed.

[0017] The contact operation is, for example, a touch operation, a tracing operation, a tap operation, etc. In the following, the contact operation is described as a touch operation as an example, but is not limited to this. The detection target detected by the detection unit 2 is the user's operating finger, but is not limited to this, and may be anything that generates electrostatic coupling with the detection electrode, such as a part of the user's body or a dedicated tool such as a stylus pen.

[0018] The control unit 4 determines whether the detected value S after the determination is the maximum detected value S max The first condition is when the detection value S falls below a predetermined rate, or when the detection value S falls by more than a predetermined rate during a predetermined period, and the touch operation is determined to be ended when at least one of the first and second conditions is satisfied.

[0019] As an example, the predetermined period may be specified by time when the detection unit 3 is configured to continuously output the detection value S, or may be specified as an integer multiple of this period when the detection unit 3 is configured to periodically output the detection value S.

[0020] The detection unit 3 of this embodiment is configured to periodically output the detection value S. Therefore, the control unit 4 periodically obtains the detection value S and outputs the maximum detection value S for a predetermined period. maxThe first detection value S obtained after a and the first detection value S a The second detection value S b is the period during which the second detection value S b is the first detection value S a The first condition is set to be a case where the value of the first voltage Vcc drops by a predetermined rate or more from the value of the first voltage Vcc.

[0021] That is, the control unit 4 detects the maximum detection value S max When the maximum detection value S max The first detection value S obtained after a and the second detection value S b In the second detection value S b is the first detection value S a or a drop of at least a predetermined rate from the threshold is satisfied, the touch operation is determined to have ended.

[0022] The control unit 4 also detects the minimum detection value S min On the other hand, the second condition is set to be a case in which the detection value S has increased by a predetermined rate or more of the determination threshold value Th.

[0023] The control unit 4 detects the minimum detection value S min If the minimum detection value S is greater than the threshold Th, the start of a touch operation cannot be determined based on the threshold Th. Therefore, the control unit 4 sets a second condition. min is greater than the threshold Th, the determination of the end of the touch operation based on the first condition and the determination of the start of a touch operation following the touch operation based on the second condition are deemed to be deemed to be deemed to be deemed to be deemed to be the minimum detection value S during the deemed determination. min A second condition is set based on the above.

[0024] (Configuration of detection unit 3) As an example, the detection unit 3 is disposed on the back surface 21 side of the operation panel 2 as shown in Fig. 1(a) and Fig. 1(b). As an example, the operation panel 2 is formed in a plate shape using a resin material. As an example, the operation surface 20 is rectangular.

[0025] The detection unit 3 is a touch sensor of a self-capacitance type or a mutual capacitance type. When the detection unit 3 is of a self-capacitance type, detection electrodes are arranged side by side in the X-axis direction and the Y-axis direction. When the operation finger 9 approaches and touches the operation surface 20, the detection unit 3 of the self-capacitance type increases the capacitance of the detection electrode that detects the operation finger 9. Therefore, the detection unit 3 may output the detected capacitance as a detection value, or may output the difference with the capacitance when no touch operation is performed as a detection value.

[0026] The detection unit 3 of this embodiment is, for example, a mutual capacitance type. As shown in Fig. 1(b), the detection unit 3 includes a plurality of X-axis detection electrodes 31 arranged so as to intersect with the X-axis, and a plurality of Y-axis detection electrodes 32 arranged so as to intersect with the Y-axis.

[0027] The X-axis detection electrode 31 and the Y-axis detection electrode 32 are formed, for example, using a highly conductive metal material such as copper. The X-axis detection electrode 31 and the Y-axis detection electrode 32 are configured by electrically connecting a plurality of rectangular detection electrodes in a row.

[0028] The detection unit 3 is configured to sequentially drive the Y-axis detection electrodes 32 and read out the capacitance from the X-axis detection electrodes 31. The detection unit 3 reads out the capacitance for all combinations of the X-axis detection electrodes 31 and the Y-axis detection electrodes 32, and outputs detection value information S, which is information related to this capacitance. 1 Output.

[0029] In the mutual capacitance type detection unit 3, when the operation finger 9 approaches and touches the operation surface 20, the capacitance of the detection electrode that detects the operation finger 9 decreases. Therefore, the detection unit 3 may invert the detected capacitance and output it as the detection value S, or may output the absolute value of the difference with the capacitance when no touch operation is performed as the detection value S. In the detection unit 3 of this embodiment, the detection value S, which is the difference, is increased by a touch operation, and the detection values ​​S of all coordinates are stored as detection value information S. 1 to the control unit 4 periodically.

[0030] (Configuration of control unit 4) The control unit 4 is a microcomputer including a CPU (Central Processing Unit) that performs calculations and processing on acquired data according to stored programs, a RAM (Random Access Memory) that is a semiconductor memory, and a ROM (Read Only Memory). The ROM stores, for example, programs for the operation of the control unit 4. The RAM is used, for example, as a storage area for temporarily storing calculation results. The control unit 4 also has a means for generating a clock signal therein and operates based on this clock signal.

[0031] The control unit 4 has a judgment threshold value Th. When the detection value S is equal to or greater than the judgment threshold value Th, the control unit 4 judges the start (ON) of a touch operation. The control unit 4 does not have a fixed threshold value for judging the end (OFF) of a touch operation, and judges the end of a touch operation according to a first condition, as described below.

[0032] The following describes the assumed determination of the start and end of a touch operation by the control unit 4 with reference to FIG.

[0033] -About the judgment of touch operation The graph of the detection value S in Fig. 2 shows the change over time of the detection value S in the case where, after one touch operation, the operating finger 9 does not leave the operation surface 20 sufficiently when performing a subsequent touch operation, as shown in Fig. 1(a) and Fig. 1(b). As an example, this detection value S is a detection value at a certain coordinate on the operation surface 20. Note that in the graph of the detection value S shown in Fig. 2, two peaks indicate that two touch operations were performed intentionally.

[0034] Time t 1 ~time t 12 The detection unit 3 detects the detected value information S 1 That is, the time t 1 ~time t 12 The detection value S shown in FIG.1 It starts to increase from time t 4 Maximum detection value S max1 The detection value S is the time t 4 From time t 7 Then it increases to time t 9 The maximum detection value of the second touch operation S max2 The detection value S is calculated as follows: 9 From time t 12 decreases to.

[0035] Comparative Example In the comparative example, the start and end of a touch operation are determined based on a determination threshold Th. As shown in FIG. 2, the comparative example is a time t 2 In this case, it is determined whether the touch operation has started (ON).

[0036] Next, the comparative example is 11 At time t 2 ~time t 11 It is determined that the touch operation, i.e., the contact of the operating finger 9 with the operating surface 20, continues for a period of time t 2 ~time t 11 In the comparative example, the coordinates are allowed to be updated based on the detected detection value S during the time t 2 ~time t 11 The coordinates are calculated each time, which causes the coordinates to be distorted.

[0037] In the present embodiment The control unit 4 of the present embodiment determines the time t 2 The control unit 4 judges the start (ON) of the first touch operation during the following time t 3 , time t 4 The detection value information S is periodically acquired. 1 The maximum value of the detection value S is updated based on this.

[0038] The control unit 4 detects a time t 5 When the detection value S is4 If the detection value S decreases below the detection value S at time t 4 The detection value S in this touch operation is the maximum detection value S max1 Then, the control unit 4 determines that the time t 4 Maximum detection value S max1 A first condition is set based on the above.

[0039] The control unit 4 detects a time t 5 The detection value S obtained after that is the maximum detection value S max1 The touch operation is determined to be ended (OFF) when at least one of the following conditions is met: the detection value becomes equal to or lower than a predetermined rate, or the detection value drops by more than a predetermined rate during a predetermined period.

[0040] First, the control unit 4 detects the maximum detection value S max1 The detection value S is a predetermined ratio of A is calculated using the following formula (1). Detection value S A = Maximum detection value S max1 ×A···(1) However, 0 <A<1 For example, when the predetermined ratio is 50%, the coefficient A is 0.5. The coefficient A may be a function.

[0041] The control unit 4 detects a time t 5 The detection value S obtained after that is the detection value S obtained by equation (1). A The detection value information S 1 is calculated each time it is obtained.

[0042] The control unit 4 also detects the maximum detection value S max1 Thereafter, the second detection value becomes equal to or smaller than the maximum detection value S from the first detection value. max1 The amount of decrease B in the detection value from the previous detection value falls to or exceeds the maximum detection value S. max1 The control unit 4 monitors whether the maximum detection value S max1 The value C determined from the maximum detection value S is calculated using the following formula (2).max1 The value C determined from is the calculated value C. Calculated value C = Maximum detected value S max1 ×D···(2) However, 0 <D<1 The coefficient D is, for example, 0.3. The coefficient D may be a function. The control unit 4 checks whether the decrease amount B is equal to or greater than the calculated value C based on the detected value information S 1 Calculate and check each time it is obtained.

[0043] As shown in FIG. 2, the control unit 4 6 The detection value S of A Since the amount of decrease B is equal to or greater than the calculated value C, it is determined that both of the first conditions are satisfied, and the touch operation is deemed to have ended (OFF). 2 ~time t 6 The period is between 10:00 and 15:00.

[0044] Next, the control unit 4 periodically acquires the detection value information S 1 The control unit 4 updates the minimum value of the detection value S based on the time t 8 At time t 7 Since the detection value S of 7 The detection value S at the minimum detection value S min This minimum detection value S min is larger than the determination threshold value Th, as shown in Fig. 2. That is, in the determination using the determination threshold value Th, the determination remains "ON" and coordinates are updated, as shown in the comparative example.

[0045] The control unit 4 determines the minimum detection value S min The control unit 4 sets the second condition based on the minimum detection value S min The minimum detection value S min It is then monitored whether the detected value S increases by a predetermined rate or more relative to the determination threshold value Th.

[0046] Minimum detection value S minThe detected value S after that is the value detected at time t 8 The control unit 4 detects the detection value S at a predetermined ratio of the judgment threshold value Th. B This is calculated using the following formula (3). Detection value S B = Threshold value Th × E (3) However, 0 <E<1 For example, when the predetermined ratio is 50%, the coefficient E is 0.5. The coefficient E may be a function.

[0047] The control unit 4 determines the minimum detection value S min Time t from 8 The control unit 4 calculates the amount of increase F in the detection value S thereafter. B The control unit 4 compares the amount of increase F with the time t 8 It is determined that the second condition is satisfied, and a deemed determination is made as to whether a second touch operation has started (ON).

[0048] The control unit 4 continues for a time t 9 , time t 10 The detection value information S is periodically acquired. 1 The control unit 4 updates the maximum value of the detection value S based on the time t 9 The detection value S in the first touch operation is the maximum detection value S max2 Then, the control unit 4 determines that the time t 9 Maximum detection value S max2 A first condition is set based on the above.

[0049] The control unit 4 detects a time t 10 The detection value S obtained after that is the detection value S obtained by equation (1). A The control unit 4 also checks whether the decrease amount B is equal to or greater than the calculated value C based on the detected value information S 1 Calculate and check each time it is obtained.

[0050] The control unit 4 detects a time t 112, the first touch operation in this embodiment is determined to be completed at time t 2 ~time t 6 During this time, the second time is at time t 8 ~time t 11 That is, in this embodiment, it is determined that the time is between t 2 ~time t 6 Coordinate updates are enabled and disabled at time t 8 ~time t 11 In this embodiment, the two touch operations intended by the user are appropriately detected, so that fluctuation in the coordinates is suppressed.

[0051] Although the two-touch operation has been described in FIG. 2, the present invention is not limited to this, and a plurality of touch operations can be deemed and determined based on the first condition and the second condition.

[0052] An example of the operation of the operation detection device 1 according to this embodiment will be described below with reference to the flowchart of FIG.

[0053] (operation) The control unit 4 of the operation detection device 1 periodically receives detection value information S from the detection unit 3. 1 If the result of step 1 is "Yes", that is, the control unit 4 obtains the detection value information S 1 When the detection value S based on becomes equal to or larger than the determination threshold value Th (Step 1: Yes), it is determined whether or not a touch operation has started (Step 2).

[0054] The control unit 4 updates the maximum detection value after the touch operation determination to the maximum detection value S max It is monitored whether the first condition based on the above is satisfied (Step 3).

[0055] When "Yes" in Step 4 is established, that is, when the first condition is established (Step 4: Yes), the control unit 4 determines that the touch operation has ended (Step 5). 1The minimum detection value is updated from the detection value S based on the min (Step 6).

[0056] The control unit 4 determines the minimum detection value S min If the threshold Th is greater than the threshold Th (Step 7: Yes), the second condition for determining whether a touch operation subsequent to the previously determined touch operation is started is satisfied or the minimum detection value S min Monitor based on this (Step 8).

[0057] If "Yes" in Step 9 is established, that is, if the second condition is established (Step 9: Yes), the control unit 4 advances the process to Step 2 and determines whether a touch operation has started.

[0058] In step 7, the control unit 4 determines the minimum detection value S min If the determination threshold value Th is equal to or smaller than the determination threshold value Th (Step 7: No), the process proceeds to step 1 to determine whether or not a touch operation has occurred using the determination threshold value Th. Note that while the control unit 4 is determining whether or not a touch operation has occurred, it updates the coordinates and calculates operation information S based on the calculated coordinates. 2 Output.

[0059] (Effects of the embodiment) The operation detection device 1 according to the present embodiment can suppress the blurring of coordinates. Specifically, the operation detection device 1 determines the end of a touch operation not by a fixed threshold value but by a maximum detection value S max The start of the subsequent touch operation is determined based on a first condition based on the minimum detection value S min Therefore, the operation detection device 1 is unlikely to determine the start and end of a touch operation depending on the characteristics of the operating finger 9, such as the size and shape, and is able to detect an appropriate touch operation according to the user's intention by suppressing erroneous determination that a state in which the operating finger 9 is floating above the operation surface 20 is a continuation of the touch operation. Therefore, the operation detection device 1 suppresses unnecessary movement of coordinates, and can suppress blurring of coordinates.

[0060] The operation detection device 1 detects a maximum detection value S maxSince the end of the touch operation is determined by the first condition based on the minimum detection value S, the operation detection device 1 can determine the end of the touch operation at an appropriate position corresponding to various contact states of the operating finger 9, as compared with a case where this configuration is not adopted. min Since the start of a continuous touch operation after the end of a touch operation can be determined by the second condition based on and the judgment threshold value Th, it is possible to stably perform a default judgment of the start of a touch operation in response to various contact states of the operating finger 9, compared to a case in which this configuration is not adopted.

[0061] Since the operation detection device 1 suppresses the shaking of coordinates, operability is improved compared to a case where the coordinates are shaken.

[0062] The operation detection device 1 is mounted on a vehicle, and therefore can properly detect a touch operation even when the operating finger 9 does not fully separate from the operation surface 20 due to vibrations of the vehicle.

[0063] Although some embodiments and modifications of the present invention have been described above, these embodiments and modifications are merely examples and do not limit the invention according to the claims. These novel embodiments and modifications can be implemented in various other forms, and various omissions, substitutions, modifications, etc. can be made without departing from the gist of the present invention. In addition, not all combinations of features described in these embodiments and modifications are necessarily essential to the means for solving the problems of the invention. Furthermore, these embodiments and modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0064] 1... operation detection device, 3... detection unit, 4... control unit, 20... operation surface,

Claims

1. a detection unit that detects a touch operation on the operation surface and outputs a detection value based on electrostatic capacitance that is increased compared to before the touch operation; a determination unit having a determination threshold for determining a start of a touch operation, determining the start of the touch operation when the detection value becomes equal to or greater than the determination threshold, and determining the end of the touch operation when a first condition based on a maximum detection value after the determination is satisfied; Equipped with the determination unit determines whether the detection value after determining the start of the touch operation is equal to or less than a predetermined first rate of the maximum detection value and whether the detection value has dropped from the maximum detection value by a predetermined second rate or more during a predetermined period, determines that the first condition is a case in which the detection value after determining the start of the touch operation is equal to or less than the first rate of the maximum detection value and a case in which the detection value has dropped from the maximum detection value by the second rate or more during the predetermined period, and determines that the touch operation is ended when at least one of these conditions is satisfied. Operation detection device.

2. the determination unit determines that a touch operation subsequent to the touch operation has been performed when a second condition based on a minimum detection value after the determination of the end of the touch operation is satisfied. The operation detection device according to claim 1 .

3. The detection unit periodically outputs the detection value, the determination unit periodically acquires the detection value, defines the predetermined period as a period for acquiring a first detection value acquired after the maximum detection value and a second detection value subsequent to the first detection value, and defines a case in which the second detection value has decreased from the first detection value by at least the second rate determined from the maximum detection value as one of the first conditions. The operation detection device according to claim 2 .

4. the determination unit determines that the second condition is met when the detection value detected after the minimum detection value increases from the minimum detection value by a third rate or more of the determination threshold value. The operation detection device according to claim 2 .

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