JPH10111690A - Position of hitting point detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position of hitting point detector capable of detecting a position of hitting point correctly with a simple structure. SOLUTION: The analog waveform A outputted from a batting sensor 21 is converted into a digital waveform by an A/D converter circuit 32 and a waveform B in which a DC component is removed by passing the digital waveform through a DC cutting filter 33 is obtained and a waveform C is obtained by subjecting the waveform B to a full-wave rectification in a rectifier circuit 34. The maximum value of the first half-wave of the waveform C subjected to the full-wave rectification is detected in a first half-wave detecting circuit 35 and a first half-wave maximum value detecting circuit 36 and, also, the maximum value of the waveform C is detected in an input waveform maximum vaue detecting circuit 37 and, then, the position of hitting point is determined by comparing and calculating the maximum value of the first half-wave of the waveform C and the maximum value of the waveform C in a comparing and calculating circuit 38.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hit point position detecting device for detecting a hit point position on a hitting surface of a hitting pad.

[0002]

2. Description of the Related Art A hitting pad which has a hitting surface on which a hit is given and which outputs a vibration waveform corresponding to the hitting given on the hitting surface has been known. 2. Description of the Related Art There is known a hit point position detecting device which inputs a vibration waveform and detects a hit point position on a hitting surface based on the vibration waveform.

Japanese Patent Application Laid-Open No. 3-107900 discloses a first electrode bonded to a lower surface of a hitting surface, a pressure-sensitive resistance element bonded to a lower surface of the first electrode, and a pressure-sensitive resistor element. A resistive surface provided at a lower portion; and a second electrode and a third electrode provided on the resistive surface. When the striking surface is struck, the struck portion of the pressure-sensitive resistance element is moved to the resistive surface. There has been proposed a technique for detecting a hitting position based on the ratio of the resistance between the second and third electrodes determined by contact with each other.

[0004] Japanese Patent Application Laid-Open No. 5-143071 discloses that
Utilizing that the first half wave of the vibration waveform output from the vibration sensor provided on the striking pad rises to the + side when the center position of the striking pad is hit, and rises to the-side when the outer peripheral position is struck. A technique has been proposed in which the rising polarity of the half wave is detected by a polarity detection circuit, and the hit point of the hit pad is detected based on the detected polarity.

Further, Japanese Patent Application Laid-Open No. Hei 5-232943 discloses a technique in which a plurality of vibration sensors are provided on a striking surface of a striking pad, and a striking position is detected based on a time difference until the vibration reaches each of the plurality of vibration sensors. Proposed.

[0006]

However, the first electrode, the pressure-sensitive resistance element, the resistance surface, and the second and third electrodes, which are proposed in JP-A-3-107900, are provided on the lower surface of the hitting surface. With the technology provided, although the hit position is accurately detected, there is a problem that the structure is complicated and the cost is high.

The technique proposed in Japanese Patent Application Laid-Open No. 5-130771 requires a polarity detection circuit for detecting the rising polarity of the first half wave of the vibration waveform output from the vibration sensor. Also, the rising polarity of the first half-wave of the vibration waveform output from the striking pad may differ depending on the manufacturer and type of the striking pad, or the polarity may be freely changed,
If a strike pad with a different polarity is connected, or the polarity is accidentally switched, etc., the strike point position when the strike position at the outer peripheral position is detected despite striking the center position of the strike pad, or There is a problem that the hit point position when the center position is hit despite the hit position is detected.

In the technique proposed in Japanese Patent Application Laid-Open No. Hei 5-232943, the hitting position is detected based on the time difference until the vibration reaches each of the plurality of vibration sensors. There are many factors due to the arrangement relationship, the transmission speed of the vibration of the vibrating body forming the impact pad, and the like, and there is a problem that it is difficult to accurately detect the impact point position. Further, since a plurality of sensors are required, the structure and the circuit become complicated, resulting in an increase in cost.

The present invention has been made in view of the above circumstances, and has as its object to provide a hit point position detecting device capable of accurately detecting a hit point position with a simple structure.

[0010]

According to a first aspect of the present invention, there is provided a hitting point position detecting device having a hitting surface to which a hit is applied, and outputting a vibration waveform corresponding to the hitting applied to the hitting surface. A hitting point detecting device connected to the hitting pad for detecting the hitting position on the hitting surface based on the vibration waveform input from the hitting pad and the vibration waveform; First detecting means for detecting a first quantity having a correlation with the amplitude of the initial half-wave after the impact of the vibration waveform (1-2) a second means having a correlation with the power of the vibration waveform
(1-3) Based on the first amount and the second amount,
A hit point position calculating means for obtaining a hit point position in the hitting surface is provided.

[0011] The first hit point position detecting device of the present invention provides a first quantity (for example, an initial half after the impact) having a correlation with the amplitude of the initial half wave after the impact of the vibration waveform from the impact pad. A second quantity having a correlation between the amplitude of the wave itself, the peak of the instantaneous power waveform of the initial half-wave, or the integrated power of the half-wave, and the power of the vibration waveform (for example, rectification of the vibration waveform) Since the hitting position is detected based on the integrated power afterward or the maximum amplitude of the vibration waveform), the first electrode, the pressure-sensitive resistance element, the resistance surface, 2. The structure is simpler and the cost can be reduced as compared with the hit point position detecting device provided with the third electrode. In addition, compared with a conventional hitting position detecting device that detects the rising polarity of the first half wave of the vibration waveform and detects the hitting position based on this, it is caused by a difference in the rising polarity of the half wave by the hitting pad, etc. False detection is prevented.
Furthermore, compared to the conventional hitting position detecting device that detects the hitting position based on the time difference until the vibration reaches each of the vibration sensors, the hitting position can be accurately detected, and the cost can be reduced. Can be

Here, the first detecting means determines the first half-wave after impact or the next half-wave following the first half-wave of the vibration waveform according to a predetermined selection criterion. It is effective to adopt it as a wave. The first half-wave after the impact included in the vibration waveform from the impact pad is a distorted waveform and may not rise up cleanly. Therefore, it is determined whether or not the first half wave is a waveform having valid information, and depending on whether the first half wave after impact is a half wave having valid information, When the half wave or the next half wave following the first half wave is adopted as the initial half wave, for example, the rise of the vibration waveform is disturbed by noise, and the value of the first half wave is extremely small. Even if the value is not valid, highly accurate detection is performed by treating the next half wave following the first half wave as the initial half wave.

[0013] The first detecting means may detect the half-wave immediately before the half-wave of the vibration waveform having an amplitude that first exceeds a threshold value determined based on the second quantity by the initial wave. Is preferably adopted as the half-wave of. As described above, when the half wave immediately before the half wave having the amplitude exceeding the threshold value determined based on the second amount is adopted as the initial half wave, for example, the rise of the vibration waveform is disturbed by noise, for example. Even if the value of the first half-wave and the value of the next half-wave following the first half-wave are extremely small and are not effective in performing the detection, the half-wave after the third wave is regarded as the initial half-wave. More accurate detection is performed by handling.

According to a second aspect of the present invention, there is provided a hitting position detecting device which has a hitting surface to which a hit is applied and which outputs a vibration waveform corresponding to the hitting applied to the hitting surface. A hit point position detecting device connected to the vibration pad, which receives the vibration waveform output from the hitting pad, and detects a hit point position on the hitting surface based on the vibration waveform. (2-1) Envelope of the vibration waveform Third detection means for detecting a third quantity having a correlation with the inclination of the line in a predetermined section after the impact (2-2) a second quantity having a correlation with the power of the vibration waveform
(2-3) Based on the third amount and the second amount,
A hit point position calculating means for obtaining a hit point position in the hitting surface is provided.

A second hitting position detecting device according to the present invention is characterized in that a third quantity (for example, the inclination itself) having a correlation with the inclination of the envelope of the vibration waveform from the striking pad within a predetermined section after striking. ) And a second quantity having a correlation with the power of the vibration waveform (for example, the maximum amplitude described above),
The position of the hit point on the hitting surface is determined. Since the envelope of the vibration waveform and the inclination of the envelope can be easily obtained by the envelope detection circuit and the inclination detection circuit, it is possible to accurately detect the hitting position with a simple circuit configuration.

Here, in the first hitting point position detecting device and the second hitting point position detecting device of the present invention, the second detecting means sets the second quantity as a correlation with the maximum amplitude of the vibration waveform. It is preferable to detect the amount having As described above, when an amount having a correlation with the power of the vibration waveform output from the impact pad is detected as an amount having a correlation with the maximum amplitude of the vibration waveform, only the maximum amplitude of the vibration waveform can be detected, and the circuit The configuration is simplified.

Further, a third aspect of the present invention for achieving the above object.
Is connected to a striking pad that has a striking surface to which a striking is applied and outputs a vibration waveform corresponding to the striking applied to the striking surface, and inputs the vibration waveform output from the striking pad. A hit point position detecting device for detecting a hit point position in the hitting surface based on the vibration waveform; (3-1) filtering for generating a plurality of vibration waveforms having different frequency component ratios from the vibration waveform; Means (3-2) Fourth detecting means for detecting a plurality of fourth quantities each having a correlation with the power of each of the plurality of vibration waveforms generated by the filtering means (3-3) And a hit point position calculating means for obtaining a hit point position in the hitting surface based on the fourth amount.

Since the third hitting position detecting device of the present invention detects the hitting position based on the ratio of the frequency components of the vibration waveform from the hitting pad, the hitting position can be detected by a simple circuit configuration such as a band-pass filter. It can be detected accurately. Here, it is preferable that the fourth detector detects an amount having a correlation with the maximum amplitude of the vibration waveform generated by the filtering unit as the fourth amount.

As described above, when the fourth quantity is detected as a quantity having a correlation with the maximum amplitude of the vibration waveform, only the maximum amplitude of the vibration waveform can be detected, as described above, and the circuit configuration is further simplified. Is done.

[0020]

Embodiments of the present invention will be described below. FIG. 1 is a block diagram of an electronic percussion instrument incorporating a hit point position detecting device according to an embodiment of the present invention. The striking sensor 11 is attached to a striking pad having a striking surface, and outputs an analog waveform (vibration waveform) corresponding to the striking of the striking surface. As the impact sensor 11, a pressure sensor, a piezoelectric sensor, or the like is used.

The hitting point / hitting force detecting section 12 corresponds to the hitting point detecting device according to the present invention, and its contents will be described later with reference to some embodiments.
And outputs hitting position information and hitting force information based on the input analog waveform.
The tone generator 13 converts the timbre information from the parameter controller 15 to be described later into a table address in the ROM 16, reads out the waveform data stored in the address from the ROM 16, and generates a musical tone according to the timbre information.

The operator group 14 is a group of operators for setting parameters such as the timbre of a musical tone to be produced in response to a strike. The operator group 14 includes, for example, the diameter of the head of an acoustic drum, Parameters such as the depth, material, and shape of the body are input. As a method of input, a method using a tone selection switch, a method of directly inputting various parameters according to volume, or the like, or
There is a method of inputting those combinations as a patch.

The parameter control unit 15 controls the parameters input by operating the operator group 14,
The striking point position from the striking force detection unit 12, the striking force information, timbre information (various coefficients for controlling the sound source unit 13), and display information are output. The ROM 16 stores waveform data of various percussion sounds, and supplies waveform data corresponding to timbre information from the parameter control unit 15 to the sound source unit 13.

The display 17 displays the setting state of the tone based on the display information from the parameter control unit 15. As a display method, the shape of the acoustic drum corresponding to the tone color information (diameter of the head portion of the drum, depth of the body portion, material, shape, etc.) is graphically displayed. By associating the shape of the acoustic drum with the timbre in this way, the timbre can be replaced with the shape of the acoustic drum, and the timbre can be intuitively understood.

FIG. 2 is a block diagram showing a first embodiment of the first hit point position detecting device of the present invention. FIG. 3 is a block diagram showing the vibration waveform of the hit point position detecting device output from the hit sensor. It is a figure showing the first half wave (first half wave). First, the waveform shown in FIG. 3 will be described. FIG. 3 shows the first one of the vibration waveforms output from the impact sensor when the center position of the impact pad and a plurality of positions from the center position of the impact pad toward the outer periphery are hit with a predetermined strength. Half waves are shown. When observing the vibration waveform output from the impact sensor when the impact pad is hit, as shown in FIG. 3, the amplitude of the first half wave of the oscillation waveform output when the center position is hit with a predetermined strength is shown. Is a relatively large ratio of the vibration waveform output from the impact sensor to the maximum amplitude, while the vibration waveform output when a plurality of positions from the center position toward the outer periphery are hit with a predetermined strength. Although the amplitude of the first half-wave gradually increases as approaching the outer peripheral position, the ratio of the vibration waveform output from the impact sensor to the maximum amplitude shows a characteristic relatively smaller than when the center position is hit.

Therefore, the amplitude of the first half wave of the vibration waveform output from the impact sensor when the outer peripheral position is hit is
The first half wave of the vibration waveform output from the impact sensor when the center position is hit so as not to exceed a value obtained by dividing the maximum amplitude of the vibration waveform by a constant value “waveform maximum value / constant value” Is set so that the amplitude of the waveform exceeds the “waveform maximum value / constant value”. Then, the amplitude of the initial half-wave of the vibration waveform output when the center position is hit is always larger than “waveform maximum value / constant value”. As described above, a threshold value indicating a criterion for determining whether the amplitude of the initial half-wave is large (the center position is hit) or small (the outer position is hit) is set by the function of the "maximum waveform value". Can be. The hit point position detecting device of the present embodiment focuses on such a viewpoint.

The striking sensor 21 shown in FIG. 2 uses a piezoelectric element, and the striking sensor 21 is attached to a striking surface of a striking pad. This impact sensor 21
An analog waveform A corresponding to the impact is output. The A / D conversion circuit 32 constituting the hit position detecting device of the present embodiment receives the analog waveform A from the impact sensor 21 and converts the input analog waveform A into a digital waveform.

The DC cut filter 33 is a high-pass filter that removes a DC component, removes the DC component of the input digital waveform, and outputs a waveform B from which the DC component has been removed. The rectifier circuit 34 outputs the waveform C by full-wave rectifying the input waveform B (turning the negative waveform back in the positive direction).

The first half-wave detecting circuit 35 detects the first half-wave C1 by detecting the rising of the input waveform C and the first zero cross. The first half-wave maximum value detecting circuit 36 (first detecting means according to the present invention) is a first half-wave C
The maximum value (amplitude) C1 _MAX of 1 is detected. The input waveform maximum value detection circuit 37 (second detection means according to the present invention) provides a maximum value (maximum amplitude) within a predetermined time from the rise of the waveform C.
Detect C _MAX .

[0030] (dot position calculating means of the present invention) comparison and calculation circuit 38 calculates the ratio between the maximum value C _MAX of the maximum value C1 _MAX and the waveform C of the first half-wave C1, based on the ratio RBI Output location information. FIG. 4 is a flowchart of a routine processed by the comparison / arithmetic circuit shown in FIG.

First, in step S11, the first half wave C
1 of the maximum value C1 _MAX is the maximum value C _MAX a fixed value of the waveform C (RATE) whether the value α is smaller than the division in or not. If it is determined that the maximum value C1 _MAX of the first half-wave C1 is less than the value α, the process proceeds to step S12 because the hitting position is off the center. In step S12, the maximum value C1 _MAX of the first half-wave C1 is substituted for the position parameter, and the process proceeds to step S14. This maximum value C1 _MAX is shown in FIG.
As described with reference to FIG.

On the other hand, if it is determined that the maximum value C _MAX of the first half-wave C1 is larger than the value α, the process proceeds to step S13 because the hit point is located at the center. In step S13, 0 is substituted for the position parameter, and the process proceeds to step S14. In step S14, it determines the value of the location parameter, the comparison and calculation to strike position and a maximum value C _{MA X} input waveform C. Thus, the maximum value C1 of the first half-wave C1
_The hit position is determined based on the ratio between _MAX and the maximum value _CMAX of the waveform C.

In this embodiment, the first half-wave detection circuit 3
5, the first half-wave C1 is detected by detecting the rising edge of the waveform C and the first zero cross, but the present invention is not limited to this, and the first half-wave C1 is detected by detecting the rising edge of the waveform C and a change in the slope. One half-wave C1 may be detected. The comparison / arithmetic circuit 38 compares / calculates the maximum value of the first half-wave C1 and the value obtained by dividing the maximum value of the waveform C by a constant value. However, the present invention is not limited to this.
Comparison and calculation may be performed based on the maximum value of the first half-wave C1 and the maximum value of the waveform C or the value obtained using the power of the waveform C as a parameter. A first quantity having a correlation with the amplitude of the half-wave of the initial waveform after impact of the analog waveform output from
What is necessary is to perform comparison and calculation based on the second amount having a correlation with the power of the analog waveform.

FIG. 5 is a block diagram showing a second embodiment of the first hit point position detecting device of the present invention. In the hit point position detecting device of the first embodiment shown in FIG. 2, a vibration waveform having an ideal rising is assumed. However, the vibration waveform may not actually rise due to the influence of noise or the like. Therefore, in the present embodiment, as described below,
Means for preventing erroneous detection due to disturbance of rising of the vibration waveform is adopted.

The analog waveform A output from the impact sensor 21 is A / A which constitutes the hit point position detecting device of this embodiment.
The signal is converted into a digital waveform by the D conversion circuit 52,
The DC component is removed via the cut filter 53,
As a result, a waveform B is generated, and the waveform B is input to the first rectifier circuit 54. The first rectifier circuit 54 has a waveform B
Is half-wave rectified (waveform B1).

The second rectifier circuit 55 performs half-wave rectification on the negative side of the waveform B, and returns the half-wave rectified waveform to the positive side (waveform B2). The third rectifier circuit 56 performs full-wave rectification on the waveform B (waveform B3). The first first half-wave detection circuit 57
The waveform B1 from the first rectifier circuit 54 is input, and the first half wave B11 of the waveform B1 (the first half wave on the + side of the waveform B)
Is detected.

The second first half-wave detecting circuit 58 receives the waveform B2 from the second rectifier circuit 55 and inputs the first half-wave B21 of the waveform B2 (the first half-wave on the negative side of the waveform B). ) Is detected. The first maximum detection circuit 59 receives the half-wave B11 detected by the first first half-wave detection circuit 57, and detects the maximum value a of the half-wave B11. Second maximum value detection circuit 6
0 inputs the half-wave B21 detected by the second first half-wave detection circuit 58 and detects the maximum value b of the half-wave B21.

The third maximum value detection circuit 61 detects the maximum value c of the waveform B3 from the third rectification circuit 56 within a predetermined time from the rise. First half-wave / second half-wave determination circuit 6
2 is based on the time difference and the magnitude between the maximum value a of the half-wave B11 and the maximum value b of the half-wave B21.
21 is determined to be the first half-wave, and the other is determined to be the second half-wave which is the next half-wave following the first half-wave. Here, since the maximum value a is earlier and smaller in time than the maximum value b, the half-wave B11 is changed to the first half-wave and the half-wave B2.
1 is determined as the second half wave.

The comparison / arithmetic circuit 63 includes a first half-wave B11 and a second half-wave B determined by the first half-wave / second half-wave determination circuit 62.
The maximum value of 21 and the maximum value C of the waveform B3 from the third maximum value detection circuit 61 are compared and calculated as described later, and the result is output as hit point position information. FIG. 6 is a flowchart of a routine processed by the comparison / arithmetic circuit shown in FIG. 5, and FIG. 7 is a diagram showing waveforms for explaining the flowchart shown in FIG.

First, in step 21 shown in FIG.
It is determined whether the maximum value a of the first half-wave B11 is smaller than a value α obtained by dividing the maximum value c of the waveform B3 by a constant value (RATE). If it is determined that the maximum value a of the first half-wave B11 is larger than the value α, the process proceeds to step S23 because the hitting position is at the center. FIG. 7A shows a step S23.
The waveform when the process proceeds to is shown. Here, the center of the striking pad is struck, whereby the DC cut filter 5 is struck.
3 shows a waveform B output from the third and a waveform B3 including the first half-wave B11 and the second half-wave B21 obtained by full-wave rectifying the waveform B by the third rectifier circuit 56. FIG. 7 (a)
As shown in the figure, the maximum value a of the first half-wave B11 exceeds the value α (maximum value / RATE). In step S23, 0 is substituted for the position parameter, and the process proceeds to step S26.

On the other hand, the maximum value a of the first half wave B11 is the value α
If it is determined that the distance is less than the center, the hit position is off the center, and the process proceeds to step S22. h step S22
Then, it is determined whether or not the maximum value b of the second half-wave B21 is smaller than the value α. When it is determined that the maximum value b of the second half-wave B21 is less than the value α, the process proceeds to step S24. FIG. 7B shows a waveform when the process proceeds to step S24. Here, a position deviated from the center of the striking pad is struck, whereby the rising edge of the waveform B is disturbed.
And a waveform B3 including the first half-wave B11 and the second half-wave B21, in which the waveform B is full-wave rectified. FIG.
As shown in (b), the maximum value b of the second half wave B21 is the value α
Is less than. In step S24, the maximum value b of the second half-wave B21 is substituted for the position parameter, and step S2
Proceed to 6. In this way, when the rise of the vibration waveform is disturbed, the maximum value a of the first half wave B11 is extremely small, and when the second half wave is regarded as the substantial first half wave, the maximum value b of the second half wave B21 is determined as follows. By substituting for the position parameter, erroneous detection due to vibration waveform disturbance is prevented.

On the other hand, if it is determined that the maximum value b of the second half-wave B21 is larger than the value α, the process proceeds to step S25. FIG. 7C shows a waveform when the process proceeds to step S25. Here, a position deviated from the center of the striking pad is struck, and thereby the DC cut filter 53
B3 and a waveform B3 including the first half-wave B11 and the second half-wave B21 obtained by full-wave rectifying the waveform B.
Are shown. As shown in FIG. 7C, the maximum value b of the second half-wave B21 exceeds the value α. Step S25
Then, the maximum value a of the first half-wave B11 is substituted for the position parameter, and the process proceeds to step S26.

In step S26, the position of the hit point is determined by comparing and calculating the value of the position parameter and the maximum value c of the waveform B3. In the present embodiment, the first rectifier circuit 54,
A pair of the first first half-wave detection circuit 57 and the second rectifier circuit 5
5, the first and second half-waves are detected by the pair of the second first half-wave detection circuits 58, but the present invention is not limited to this. After full-wave rectification, the rise of the waveform, zero crossing or slope , The first and second half-waves may be detected.

Further, as a more reliable method, detection of the third and subsequent half waves may be performed. In other words, the (n−n) -th half-wave that precedes the “waveform maximum value” / “constant value” first,
1) A half wave may be used as the hit point position parameter. FIG.
It is a block diagram showing one embodiment of a second hit point position detecting device of the present invention. 9 is a diagram showing a vibration waveform (a) output from the impact sensor and an envelope waveform (b) of the vibration waveform, and FIG. 10 is a diagram showing the slope and velocity (strength of the impact) of the envelope waveform shown in FIG. FIG. 11 is a graph showing the relationship of FIG.
FIG. 7 is a diagram showing a vibration waveform corresponding to each point of the graph shown in FIG.

First, the waveform shown in FIG. 9 will be described.
The envelope of the vibration waveform from the impact sensor shown in FIG. 9A is obtained, and the envelope waveform shown in FIG. 9B is obtained.
The levels corresponding to the two points on this envelope waveform are A,
Assuming B, the slope of this envelope waveform at a predetermined time T is expressed as (BA) / T.

Point A shown in the graph of FIG. 10 shows the relationship between the velocity and the slope of the envelope waveform when the inside (center position) of the striking pad is strongly struck.
And the slope of the envelope waveform. Point B shows the relationship between the velocity and the slope of the envelope waveform when the inside of the striking pad is lightly hit, and corresponds to the vibration waveform and the slope of the envelope waveform shown in FIG. Point C shows the relationship between the velocity and the slope of the envelope waveform when the outside (outer peripheral position) of the striking pad is strongly struck.
This corresponds to the vibration waveform shown in (c) and the slope of its envelope waveform. Point D indicates the relationship between the velocity and the slope of the envelope waveform when the outside of the hit pad is hit lightly, and corresponds to the vibration waveform and the slope of the envelope waveform shown in FIG. 10 and 11
As is clear from FIG. 5, the slope of the envelope waveform changes depending on the hitting position and hitting strength of the hitting pad. In the present embodiment, the hit point position is detected by focusing on this point.

The analog waveform A output from the impact sensor 21 shown in FIG. 8 is converted into a digital waveform by the A / D conversion circuit 112 constituting the hit point detecting device of the present embodiment, and further passes through the DC cut filter 113. As a result, a waveform B from which the DC component has been removed is generated, and the waveform B is input to the rectifier circuit 114. The rectifier circuit 114 performs full-wave rectification on the waveform B from the DC cut filter 113 to generate a waveform C.
Is output.

The envelope detection circuit 115 detects the envelope (envelope) of the waveform C that has been full-wave rectified by the rectification circuit 114, and outputs an envelope waveform D as shown in FIG. The inclination detection circuit 116 (third detection means according to the present invention) detects an inclination of a certain section T of the envelope waveform D.

The maximum value detection circuit 117 includes a rectifier circuit 114
To detect the maximum value within a predetermined time from the rise of the full-wave rectified waveform C. The comparison / calculation circuit 118 compares / calculates the slope of the fixed section T of the envelope waveform D with the maximum value of the waveform C, and outputs the result as hit point position information. In the present embodiment, the waveform B from the DC cut filter 113 is full-wave rectified using the rectifier circuit 114. However, the present invention is not limited to this, and the waveform B from the DC cut filter 113 is half-wave rectified. Is also good. Alternatively, a plurality of peak values (levels) in the envelope waveform D may be detected by the slope detection circuit 116, and a plurality of slopes determined by the plurality of peak values may be detected. Further, in the comparison / calculation circuit 118, not only the value of the slope but also the peak value when the slope is detected may be used as a parameter for the calculation.

FIG. 12 is a block diagram showing an embodiment of the third hit point position detecting device of the present invention. The hit point position detecting device of the present embodiment detects the hit point position by focusing on the characteristic that the frequency component of the vibration waveform output from the hit sensor changes depending on the hit point position.

An analog waveform A output from the impact sensor 21 (piezoelectric sensor) is converted into a digital waveform by an A / D conversion circuit 122 constituting the hit point position detecting device of the present embodiment, and passes through a DC cut filter 123. Thus, a waveform B from which the DC component has been removed is generated, and the waveform B is input to the first band-pass filter 124. First bandpass filter 124 (filtering means according to the present invention)
Removes the low-frequency components of the frequency components of the input waveform B and outputs a waveform C composed of high-frequency components.

The first rectifier circuit 125 performs full-wave rectification on the waveform C from the first band-pass filter 124 and outputs a waveform D. The first amplitude detection circuit 126 (fourth detection means according to the present invention) outputs the waveform D from the first rectification circuit 125.
Is detected as the maximum amplitude value (maximum value) a. The waveform B is also input to the second bandpass filter 127 (the filtering means according to the present invention). The second band-pass filter 127 removes high-frequency components from the frequency components of the input waveform B, and outputs a waveform E including low-frequency components.

The second rectifier circuit 128 performs full-wave rectification on the waveform E from the second bandpass filter 127 and outputs a waveform F. The second amplitude detecting circuit 129 (fourth detecting means according to the present invention) outputs the waveform F from the second rectifying circuit 128.
Is detected as the maximum amplitude value (maximum value) b. The comparison / calculation circuit 130 compares and calculates the maximum values a and b obtained by the first and second amplitude detection circuits 126 and 129, and outputs the result as hit point position information.

As described above, in the present embodiment, the hit point is detected based on the ratio of the frequency components of the input vibration waveform. Therefore, a simple band-pass filter or the like may be used, and the circuit configuration may be simplified. At the same time, the hitting position can be accurately detected. In this embodiment, a piezoelectric sensor is used as the impact sensor 21, but a microphone or another sensor may be used as long as it outputs a vibration waveform (a waveform including a frequency component). The first and second bandpass filters 12 are used to extract the frequency component of the vibration waveform.
Although 4,127 was used, another filter may be used as long as it can extract a characteristic frequency band that changes depending on the difference in the hitting position, or the first and second bandpass filters 124,127 may be used. Either one may be through (no filter).

Also, the first and second rectifier circuits 125 and 128
However, half-wave rectification (only in the minus direction and only in the plus direction) may be used. Further, the maximum amplitude value is detected by the first and second amplitude detection circuits 126 and 129, but the value may be detected at a point in time when a predetermined time has elapsed from the rise of the waveform. Further, the number of sets of the bandpass filter, the rectifier circuit, and the amplitude detection circuit may be three or more.

[0056]

As described above, according to the hit position detecting device of the present invention, the hit position can be accurately detected with a simple structure.

[Brief description of the drawings]

FIG. 1 is a block diagram of an electronic percussion instrument incorporating a hit point position detecting device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a first embodiment of a first hit point position detecting device of the present invention.

FIG. 3 is a diagram showing the first half wave (first wave) of the vibration waveform output from the impact sensor shown in FIG. 2 and input to the hit point position detecting device;
FIG.

FIG. 4 is a flowchart of a routine processed by a comparison / arithmetic circuit shown in FIG. 2;

FIG. 5 is a block diagram showing a second embodiment of the first hitting position detecting device of the present invention.

FIG. 6 is a flowchart of a routine processed by the comparison / arithmetic circuit shown in FIG. 5; FIG. 7 is a diagram showing waveforms for explaining the flowchart shown in FIG. 6.

FIG. 7 is a diagram showing waveforms for explaining the flowchart shown in FIG. 6;

FIG. 8 is a block diagram showing an embodiment of a second hitting position detecting device of the present invention.

FIG. 9 is a diagram showing a vibration waveform (a) output from the impact sensor and an envelope waveform (b) of the vibration waveform.

10 is a graph showing the relationship between the slope of the envelope waveform shown in FIG. 9 and the velocity (strength of impact).

11 is a diagram showing a vibration waveform corresponding to each point of the graph shown in FIG. 10 output from the impact sensor and a slope of an envelope waveform thereof.

FIG. 12 is a block diagram showing an embodiment of a third hitting position detecting device of the present invention.

[Explanation of symbols]

11, 21 Impact sensor 12 Hitting position / hitting force detection unit 13 Sound source unit 14 Operator group 15 Parameter control unit 16 ROM 17 Display 32, 52, 112, 122 A / D conversion circuit 33, 53, 113, 123 DC cut Filters 34, 54, 55, 56, 114, 125, 128 Rectifier circuits 35, 57, 58 First half-wave detection circuit 36 First half-wave maximum value detection circuit 37 Input waveform maximum value detection circuit 38, 63, 118, 130 Comparison / arithmetic circuit 59, 60, 61, 117 Maximum value detecting circuit 62 First half-wave / second half-wave determining circuit 115 Envelope detecting circuit 116 Slope detecting circuit 124, 127 Band-pass filter 126, 129 Amplitude detecting circuit

Claims (7)

[Claims] 1. A striking pad which has a striking surface to which a striking is applied and which is connected to a striking pad which outputs a vibration waveform corresponding to the striking applied to the striking surface, inputs the vibration waveform output from the striking pad, and A hit point position detecting device that detects a hit point position in the hitting surface based on a vibration waveform, wherein a first amount of the vibration waveform having a correlation with an amplitude of an initial half-wave after the hitting is detected. 1 detecting means, 2nd detecting means for detecting a second amount having a correlation with the power of the vibration waveform, and based on the first amount and the second amount, in the hitting surface. And a hit point position calculating means for calculating a hit point position. 2. The method according to claim 1, wherein the first detecting unit detects a half-wave immediately before a half-wave of the vibration waveform having an amplitude that first exceeds a threshold value determined based on the second amount. 2. The hit point position detecting device according to claim 1, wherein the hit point position detecting device is used as a half-wave. 3. The first detecting means according to a predetermined selection criterion, converts the first half-wave after the impact or the next half-wave following the first half-wave of the vibration waveform into the initial half-wave. 2. The hit point position detecting device according to claim 1, wherein the hit point position detecting device is adopted. 4. A striking pad which has a striking surface to which a striking is applied and which is connected to a striking pad for outputting a vibration waveform corresponding to the striking applied to said striking surface, inputs said vibration waveform outputted from said striking pad, and A hit point position detecting device for detecting a hit point position in the hitting surface based on a vibration waveform, wherein a third quantity having a correlation with an inclination of an envelope of the vibration waveform in a predetermined section after hitting is detected. A third detecting means for detecting a second amount having a correlation with a power of the vibration waveform; and a hitting based on the third amount and the second amount. A hit point position detecting device comprising: a hit point position calculating means for obtaining an in-plane hit point position. 5. The apparatus according to claim 1, wherein the second detecting means detects an amount having a correlation with a maximum amplitude of the vibration waveform as the second amount. Hit point position detection device. 6. A striking pad which has a striking surface to which a striking is applied and which is connected to a striking pad for outputting a vibration waveform corresponding to the striking applied to said striking surface, inputs said vibration waveform outputted from said striking pad, and A hit point position detecting device that detects a hit point position in the hitting surface based on a vibration waveform, wherein: a filtering unit that generates a plurality of vibration waveforms having different frequency component ratios from the vibration waveform; A fourth detecting unit that detects a plurality of fourth amounts each having a correlation with the power of each of the plurality of generated vibration waveforms, based on the plurality of fourth amounts, A hit point position detecting device, comprising a hit point position calculating means for obtaining a hit point position. 7. The method according to claim 1, wherein the fourth detecting means detects an amount having a correlation with a maximum amplitude of the vibration waveform generated by the filtering means as the fourth amount. Item 6. A hit point position detecting device according to Item 6.