Musical tone generating device and musical tone generating method

Abstract

The present invention provides a tone generation device and a tone generation method that can improve the sensitivity of pressing on a striking surface. The tone generation device includes: a striking surface; a pressure-sensitive sensor configured on the back side of the striking surface to detect pressure changes; an elastic body compressed between the striking surface and the pressure-sensitive sensor; and a control device that outputs an instruction corresponding to the output value of the pressure-sensitive sensor, and the control device includes: a pressing detection component that detects the pressing on the striking surface based on the difference between the output value of the pressure-sensitive sensor and a reference value; and an update component that updates the reference value according to the output value of the pressure-sensitive sensor at each update time.

Description

Technical Field

[0001] The present invention relates to a musical tone generating device and a musical tone generating method, and to a musical tone generating device and a musical tone generating method capable of improving the sensitivity of pressing on a striking surface. Background Art

[0002] In a musical tone generating device such as an electronic drum or a Musical Instrument Digital Interface (MIDI) pad controller, or a musical tone generating method using the musical tone generating device, a pressure-sensitive sensor is used to detect a situation where a striking surface is pressed with a hand or the like, or the amount of depression (intensity of pressing), and an instruction corresponding to the presence or absence of pressing or the amount of depression is output. In the electronic drum disclosed in Patent Document 1, a head board that descends when the striking surface is pressed faces a pressure-sensitive sensor with a vertical separation.

[0003] [Prior Art Documents]

[0004] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-224330 Summary of the Invention

[0006] [Problems to be Solved by the Invention]

[0007] However, in the technique disclosed in Patent Document 1, when the striking surface is weakly pressed to the extent of contact, the head board does not contact the pressure-sensitive sensor, so it is impossible to detect a situation where the striking surface is weakly pressed using the pressure-sensitive sensor, and thus there is a problem of low sensitivity of pressing on the striking surface.

[0008] The present invention is made to solve the above problems, and an object thereof is to provide a musical tone generating device and a musical tone generating method capable of improving the sensitivity of pressing on a striking surface.

[0009] [Technical Means for Solving the Problems]

[0010] To achieve the above object, the musical tone generating device of the present invention includes: a striking surface; a pressure-sensitive sensor disposed on the back side of the striking surface to detect a pressure change; an elastic body compressed between the striking surface and the pressure-sensitive sensor; and a control device that outputs an instruction corresponding to an output value of the pressure-sensitive sensor, and the control device includes: a pressing detection component that detects pressing on the striking surface based on a difference between the output value of the pressure-sensitive sensor and a reference value; and an update component that updates the reference value according to the output value of the pressure-sensitive sensor at each update time.

[0011] The tone generation method of the present invention outputs an indication corresponding to the output value of the pressure-sensitive sensor in a tone generation device including a striking surface, a pressure-sensitive sensor, and an elastic body. The pressure-sensitive sensor is arranged on the back side of the striking surface to detect pressure changes. The elastic body is compressed between the striking surface and the pressure-sensitive sensor. The tone generation method includes: a pressing detection step of detecting the pressing on the striking surface based on the difference between the output value of the pressure-sensitive sensor and a reference value; and an updating step of updating the reference value according to the output value of the pressure-sensitive sensor at each update time. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a plan view of an electronic percussion instrument in the first embodiment.

[0013] Figure 2 is Figure 1 a sectional view of the electronic percussion instrument taken along line II-II of

[0014] Figure 3 is a block diagram showing the electrical structure of the electronic percussion instrument.

[0015] Figure 4 (a) of Figure 4 is a schematic diagram showing the shapes of an envelope for crosstalk amount calculation and an envelope for crosstalk cancellation. Figure 4 of

[0016] Figure 5 (b) of Figure 5 is a voltage-time graph of the output waveform of the head vibration sensor. Figure 5 of

[0017] Figure 6 (c) of Figure 6 is a voltage-time graph of the voltage waveform of the rim vibration sensor.

[0018] Figure 7 is a flowchart of the pressing detection process.

[0019] Figure 8 is a flowchart of the percussion detection process.

[0020] Figure 9 (a) of Figure 9 is a plan view of the MIDI controller in the second embodiment. Figure 9Cross-sectional view of the MIDI controller along the IXb-IXb line in (a).

[0021] Figure 10 Is a block diagram showing the electrical structure of the MIDI controller.

[0022] Figure 11 Is a flowchart of the periodic process.

[0023] [Description of symbols]

[0024] 1: Electronic percussion instrument (musical sound generating device)

[0025] 20a, 21a, 83: Striking surface

[0026] 24: Pressure-sensitive sensor

[0027] 28: Head vibration sensor (strike detection component)

[0028] 26, 84: Elastic body

[0029] 40, 90: Control device

[0030] 43d: Reference value calculation ring buffer (storage component)

[0031] 80: MIDI controller (musical sound generating device)

[0032] S16, S22, S23, S25, S77, S90, S91, S93: Update component, update step

[0033] S17, S88: Press detection component, press detection step

[0034] S20: Press update prohibition component

[0035] S19, S22, S27, S80, S82, S90: Post-strike update prohibition component

[0036] S30, S37~S42, S44~S48: Press judgment component Detailed implementation method

[0037] Hereinafter, the preferred embodiments will be described with reference to the accompanying drawings. First, refer to Figure 1 and Figure 2 to describe the overall structure of the electronic percussion instrument (musical sound generating device) 1. Figure 1 Is a plan view of the electronic percussion instrument 1 in the first embodiment. Figure 2 Is Figure 1 Cross-sectional view of the electronic percussion instrument 1 along the II-II line. Furthermore, for easy understanding, Figure 1 the near side of the paper surface of Figure 2The upper side of [the relevant part] is set as the upper part of the electronic percussion instrument 1, and Figure 1 the inner side of the paper surface of [the relevant part] and Figure 2 the lower side of [the relevant part] are set as the lower part of the electronic percussion instrument 1. Additionally, Figure 1 the left side, right side, lower side, and upper side of the paper surface of [the relevant part] are respectively set as the left side, right side, front side (the side of the performer), and back side of the electronic percussion instrument 1.

[0038] As Figure 1 and Figure 2 shown, the electronic percussion instrument 1 is an electronic instrument that simulates a bongo drum played by a performer hitting it with hands. The electronic percussion instrument 1 mainly includes: a frame body 10; two heads 20, 21 respectively installed on the frame body 10; a rim 22 respectively provided on the outer edges of the heads 20, 21; a pressure-sensitive sensor 24 that detects the pressing on the heads 20, 21; a head vibration sensor 28 that detects the vibration of the heads 20, 21; a rim vibration sensor 32 that detects the vibration of the frame body 10; and a control device 40 that outputs a sound production instruction for musical sounds.

[0039] The electronic percussion instrument 1 is formed to be substantially symmetrical left and right. The head 20 is provided on the left side of the electronic percussion instrument 1, and the head 21 is provided on the right side of the electronic percussion instrument 1. One pressure-sensitive sensor 24, one head vibration sensor 28, and one rim vibration sensor 32 are respectively arranged for each of the heads 20, 21. Hereinafter, as long as there is no special indication, the left side of the electronic percussion instrument 1 will be described, and the description of the right side will be omitted.

[0040] The frame body 10 includes: a cylindrical shell 11; a connecting portion 13 that connects the shells 11 on the left and right sides to each other; and a frame 14 for installing the pressure-sensitive sensor 24 or the head vibration sensor 28, etc. The shell 11 is a cylindrical member with a closed lower end and an open upper end, and is formed of synthetic resin, metal, etc. The connecting portion 13 is formed in such a way that its interior is connected to the interior of the shell 11. By assembling a top case integrally formed with the upper half of the shells 11 on the left and right sides and the connecting portion 13 and a bottom case integrally formed with their lower half, the shells 11 on the left and right sides and the connecting portion 13 are formed.

[0041] The control device 40 is provided inside the connecting portion 13. A plurality of operating members 15 or a liquid crystal display (LCD) 16 electrically connected to the control device 40 are provided on the connecting portion 13. The operating members 15 or the LCD 16 are arranged on the performer side of the connecting portion 13. The operating members 15 are used to set user parameters, etc. used in the calculation of the peak ratio characteristic quantity X1 described later. The LCD 16 is a display device that displays the user parameters, etc.

[0042] The frame 14 is a substantially disk-shaped member integrally formed on the top shell of the housing 11 with an outer periphery. The frame 14 divides the interior of the housing 11 vertically and faces the head 20 vertically. A speaker 17 that emits musical sounds upward is mounted on the lower surface of the central portion in the radial direction of the frame 14. A plurality of through holes 14a penetrating in the plate thickness direction are provided in the frame 14 above the speaker 17. Thus, the musical sounds emitted upward from the speaker 17 pass through the through holes 14a and toward the head 20.

[0043] The head 20 is a film-like member that covers the upper end of the housing 11 and is formed of a mesh-like raw material. Thus, the musical sounds emitted from the speaker 17 and passing through the through holes 14a are emitted from the head 20 to the outside of the electronic percussion instrument 1. The surface (upper surface) of the head 20, i.e., the striking surface 20a, is struck by the hand of the performer or the like. The back surface 20b of the head 20 faces the frame 14. Furthermore, the surface of the head 21 that covers the upper end of the left housing 11 is the striking surface 21a.

[0044] The rim 22 is a ring-shaped member that fixes the outer edge of the head 20 throughout the circumference. By fixing the rim 22 to the outside of the upper end portion of the housing 11, the tensioned head 20 is mounted on the frame body 10. Rubber covers 22a are provided on the upper surface and the outer peripheral surface of the rim 22. Thus, the burden on the hand when the rim 22 is struck by hand can be suppressed.

[0045] The pressure-sensitive sensor 24 is a disk-shaped piezoresistive element that detects pressure changes. The circuit is configured such that the output value of the pressure-sensitive sensor 24 becomes maximum in a state where no pressure is applied to the pressure-sensitive sensor 24. The greater the pressure applied to the pressure-sensitive sensor 24, the smaller the output value of the pressure-sensitive sensor 24. The pressure-sensitive sensor 24 is mounted on the upper surface of the frame 14 so as to be on the back surface 20b side of the central portion of the head 20 (striking surface 20a). Furthermore, the central portion of the striking surface 20a preferably refers to a portion within 10% when the radial center of the striking surface 20a is set to 0% and the inner peripheral edge of the rim 22 is set to 100%. Furthermore, it is preferable that the pressure-sensitive sensor 24 is located at the radial center of the striking surface 20a.

[0046] A spacer 25 is provided around the pressure-sensitive sensor 24 except for the portion through which the wiring (not shown) connecting the pressure-sensitive sensor 24 and the control device 40 passes. The spacer 25 is a plate-like member slightly thicker than the pressure-sensitive sensor 24 and is mounted on the upper surface of the frame 14.

[0047] An elastic body 26 is mounted on the upper surface of the spacer 25. The elastic body 26 is a cushioning material in the shape of a quadrangular hammer stand formed of sponge and covers the upper part of the pressure-sensitive sensor 24. Figure 2In the figure, the elastomer 26 in the state without a load applied is shown by a two-dot dash line. The elastomer 26 is set such that the vertical dimension (axial dimension of the housing 11) in the state without a load applied is longer than the vertical dimension between the head 20 and the pressure-sensitive sensor 24 mounted in the frame 10. Thus, the elastomer 26 is compressed in the vertical direction between the head 20 (striking surface 20a) and the pressure-sensitive sensor 24.

[0048] When the striking surface 20a is struck or pressed, the pressure-sensitive sensor 24 is pressed via the elastomer 26, and the pressure-sensitive sensor 24 detects the strike or press. Since there is a spacer 25 around the pressure-sensitive sensor 24, the more strongly the striking surface 20a is pressed, the more the contact area between the pressure-sensitive sensor 24 and the elastomer 26 can be increased from the center of the pressure-sensitive sensor 24 toward the spacer 25. Thus, the output value of the pressure-sensitive sensor 24 can be easily changed according to the amount of depression of the striking surface 20a or the intensity of the strike. Furthermore, since the elastomer 26 is formed in a shape of a quadrangular hammer stand with a tapered front end toward the striking surface 20a, the pressure from the striking surface 20a can be stably applied to the pressure-sensitive sensor 24.

[0049] In addition, even when the striking surface 20a is not pressed or struck, the elastomer 26 is compressed between the striking surface 20a and the pressure-sensitive sensor 24, so there is no clearance between the striking surface 20a and the pressure-sensitive sensor 24. Thus, even when the striking surface 20a is not strongly pressed, the output value of the pressure-sensitive sensor 24 can be changed. Thereby, the sensitivity of the pressure-sensitive sensor 24 with respect to the strike or press on the striking surface 20a can be improved.

[0050] The head vibration sensor 28 is formed of a disk-shaped piezoelectric element that detects vibration. The head vibration sensor 28 is disposed on the back surface 20b side of the head 20 and is mounted on the upper surface of the frame 14 via a double-sided tape 29. The head vibration sensor 28 is located on the back side away from the player among the peripheral portions of the head 20 (striking surface 20a). Furthermore, the peripheral portion preferably refers to a portion of 70% or more when the radial center of the head 20 is set to 0% and the inner peripheral edge of the rim 22 is set to 100%.

[0051] The double-sided tape 29 is a disk-shaped member having cushioning properties. The diameter of the double-sided tape 29 is shorter than the diameter of the head vibration sensor 28. Thus, the outer peripheral side of the head vibration sensor 28 can be easily deformed, thereby ensuring the detection sensitivity of the head vibration sensor 28.

[0052] A cushion pad 30 is bonded to the upper surface (side of the head 20) of the head vibration sensor 28. The cushion pad 30 is a columnar cushioning material formed of sponge and covers above the head vibration sensor 28.

[0053] The cushion 30 is set to have a vertical dimension in the unloaded state that is longer than the vertical dimension between the head 20 mounted on the frame 10 and the head vibration sensor 28. As a result, the elastic body 26 is compressed in the vertical direction between the head 20 (the striking surface 20a) and the head vibration sensor 28. Therefore, the contact state between the head 20 vibrating due to the strike and the cushion 30 can be maintained, and thus the vibration of the peripheral portion of the head 20 (the striking surface 20a) can be accurately detected by the head vibration sensor 28. Further, in the electronic percussion instrument 1 in the present embodiment, the strike on the striking surface 20a is detected by the head vibration sensor (strike detection component) 28, and it is determined that the striking surface 20a has been struck based on the output value of the head vibration sensor 28.

[0054] When the striking surface 20a directly above the head vibration sensor 28 is struck, the output value of the head vibration sensor 28 is likely to increase sharply compared to the case where other positions of the striking surface 20a are struck. The back side of the head 20 that is far from the performer where the head vibration sensor 28 is arranged is a position that is difficult for the performer to directly strike, so a sharp increase in the output value of the head vibration sensor 28 can be suppressed. In particular, in the electronic percussion instrument 1 of the present embodiment, two striking surfaces 20a and 21a are provided on one frame 10, and the operating member 15 or the LCD 16 is located on the front side of the frame 10. Therefore, the operating member 15 or the LCD 16 can be located on the performer side and the head vibration sensor 28 can be surely located on the back side. As a result, it is difficult for the output value of the head vibration sensor 28 to increase sharply.

[0055] The rim vibration sensor 32 is formed of a disc-shaped piezoelectric element that detects vibration. The rim vibration sensor 32 is arranged at a position that overlaps with the head vibration sensor 28 when looking down at the striking surface 20a ( Figure 1 ). The rim vibration sensor 32 is mounted on the lower surface of the frame 14 via a double-sided tape 33.

[0056] The double-sided tape 33 is a ring plate-shaped member with cushioning properties. As a result, the center side of the rim vibration sensor 32 can be easily deformed, thereby ensuring the detection sensitivity of the rim vibration sensor 32. The outer diameter of the double-sided tape 33 is shorter than the diameter of the rim vibration sensor 32. As a result, the outer peripheral side of the rim vibration sensor 32 can be easily deformed, thereby ensuring the detection sensitivity of the rim vibration sensor 32.

[0057] The control device 40 is arranged inside the frame 10. The control device 40 outputs a sound generation instruction to the sound source 45 (refer to Figure 3 ), and the sound generation instruction corresponds to the output values of the pressure-sensitive sensor 24, the head vibration sensor 28, and the rim vibration sensor 32 provided for each of the striking surfaces 20a and the striking surface 21a. The control device 40 is connected to the pressure-sensitive sensor 24, the head vibration sensor 28, the rim vibration sensor 32, etc. through wiring (not shown).

[0058] Next, with reference to Figure 3 the electrical structure of the electronic percussion instrument 1 will be described. Figure 3 is a block diagram showing the electrical structure of the electronic percussion instrument 1. The control device 40 of the electronic percussion instrument 1 includes a central processing unit (CPU) 41, a read only memory (ROM) 42, and a random access memory (RAM) 43, which are respectively connected via a bus line 44. In addition, a pressure-sensitive sensor 24, a head vibration sensor 28, and a rim vibration sensor 32 on the striking surface 20a side, a pressure-sensitive sensor 24, a head vibration sensor 28, and a rim vibration sensor 32 on the striking surface 21a side, an operating member 15, an LCD 16, and a sound source 45 are respectively connected to the bus 44. A digital-to-analog converter (DAC) 46 is connected to the sound source 45, an amplifier 47 is connected to the DAC 46, and a speaker 17 is connected to the amplifier 47.

[0059] When the striking surfaces 20a and 21a are struck by hand, the electronic percussion instrument 1 outputs a sound generation instruction from the CPU 41 to the sound source 45, and the sound generation instruction corresponds to the detection results (output values) of the pressure-sensitive sensor 24, the head vibration sensor 28, and the rim vibration sensor 32 based on the strike. The sound source 45 is a device that controls the timbre or various effects of the musical sound (striking sound) according to the sound generation instruction from the CPU 41. Although not shown in the sound source 45, a digital signal processor (DSP) that performs arithmetic processing such as filtering of waveform data or effects is built in. The electronic percussion instrument 1 converts the digital musical sound signal processed by the sound source 45 into an analog signal using the DAC 46, amplifies the signal using the amplifier 47, and emits the musical sound based on the musical sound signal from the speaker 17.

[0060] Since the electronic percussion instrument 1 is provided with two striking surfaces 20a and 21a in one housing 10, it is possible to generate a sound generation instruction or a musical sound signal in such a manner that the musical sound accompanying the strike of the striking surface 20a is different from the musical sound accompanying the strike of the striking surface 21a. Thus, the electronic percussion instrument 1 can simulate the playing method of an acoustic bongo drum with different timbres for each of the striking surfaces 20a and 21a.

[0061] The CPU 41 is an arithmetic unit that controls each part connected via the bus 44. The ROM 42 is a non-rewritable memory. The control program 42a and the weighting coefficient data 42b are stored (saved) in the ROM 42. When the control program 42a is executed by the CPU 41, initialization processing ( Figure 6 as shown in (a)) is executed immediately after the power of the electronic percussion instrument 1 is turned on, and then periodic processing is executed.

[0062] In addition, although not shown in the control program 42a, it includes a crosstalk cancellation program (crosstalk cancellation component). Crosstalk, for example, refers to the case where when the striking surface 20a is struck, the vibration caused by the strike is transmitted to the striking surface 21a side. Crosstalk cancellation is a process of not emitting a musical sound based on the vibration of the striking surface 21a even if the head vibration sensor 28 detects the vibration of the striking surface 21a caused by the crosstalk. As long as it is a program capable of performing crosstalk cancellation, a known crosstalk cancellation program can be optimized and used in this embodiment.

[0063] Refer to Figure 4 as shown in (a) to Figure 4 as shown in (c) to describe the crosstalk cancellation program. In the following description, the case where the striking surface 20a is struck and the striking surface 21a is affected by crosstalk is described, but it can be said that the same applies to the case where the striking surface 21a is struck and the striking surface 20a is affected by crosstalk. In addition, when the output value of the head vibration sensor 28 on the striking surface 20a (the latest value of the head sensor value ring buffer 43a) exceeds the strike threshold N1 (refer to Figure 5 as shown in (b)), it is called that a trigger signal from the striking surface 20a is output, and the peak value of the head vibration sensor 28 of the striking surface 20a at this time is called the level of the trigger signal. The same applies to the output value of the head vibration sensor 28 on the striking surface 21a.

[0064] As Figure 4 shown in (a) to Figure 4 as shown in (c), crosstalk cancellation uses the crosstalk amount calculation envelope 71 and the crosstalk cancellation envelope 72. Figure 4 Figure (a) shows a schematic diagram of the shapes of the crosstalk amount calculation envelope 71 and the crosstalk cancellation envelope 72. Furthermore, in Figure 4 Figure (a), the horizontal axis represents time and the vertical axis represents level.

[0065] The crosstalk amount calculation envelope 71 is an envelope used to calculate a value representing the degree of crosstalk that the striking surface 21a receives from the striking surface 20a (that is, the crosstalk amount). On the other hand, the crosstalk cancellation envelope 72 is an envelope used to determine whether to perform crosstalk cancellation on the trigger signals input from the striking surfaces 20a and 21a.

[0066] The envelope line 71 for crosstalk amount calculation and the envelope line 72 for crosstalk cancellation are both imaginary envelope lines that mimic the vibration states of the striking surfaces 20a and 21a that output the trigger signal to be generated, and as shown in Figure 4 (a) of, it is generated based on the level of the trigger signal to be generated. Specifically, the envelope line 71 and the envelope line 72 are represented by the following linear function. That is, when the trigger signal to be generated occurs at time t1, the level L of the trigger signal at time t1 becomes zero at time t2 after a certain period of time (200 milliseconds in this embodiment). That is, the greater the level of the trigger signal to be generated, the greater the reduction slope for both the envelope line 71 for crosstalk amount calculation and the envelope line 72 for crosstalk cancellation.

[0067] The trigger signal to be generated is the trigger signal from the striking surface 20a determined to be struck for the envelope line 71 for crosstalk amount calculation. That is, only one envelope line 71 for crosstalk amount calculation is generated for the striking surface 20a determined to be struck.

[0068] On the other hand, the trigger signal to be generated for the envelope line 72 for crosstalk cancellation is the trigger signal from the striking surface 20a determined to be struck or the trigger signal from the striking surface 21a determined to sound due to crosstalk received from the striking surface 20a. That is, one or more envelope lines 72 for crosstalk cancellation are generated for the striking surface 20a determined to be struck and the striking surface 21a that receives crosstalk but sounds. Furthermore, the envelope line 72 for crosstalk cancellation generated for the striking surface 20a determined to be struck becomes an envelope line with the same shape as the envelope line 71 for crosstalk amount calculation.

[0069] Figure 4 (b) of is a diagram illustrating the method of calculating the crosstalk amount using the envelope line 71 for crosstalk amount calculation. The crosstalk amount is calculated as the ratio of the current value in the envelope line 71 for crosstalk amount calculation to the input trigger signal when a trigger signal is input from the striking surface 21a and the envelope line 71 for crosstalk amount calculation with respect to the striking surface 20a has been generated.

[0070] Specifically, when the level of the trigger signal input from the striking surface 21a at time x1 is set as y1b and the current value of the envelope line 71 for crosstalk amount calculation generated with respect to the striking surface 20a at time x1 is set as y1a, the crosstalk amount (%) received by the striking surface 21a is calculated as (y1b / y1a)×100.

[0071] Figure 4Figure (c) is a diagram illustrating a method for determining crosstalk cancellation using the crosstalk cancellation envelope 72. The determination of whether to perform crosstalk cancellation on the trigger signal from the hitting surface 20a or the hitting surface 21a is made using the envelope 72 in the generated crosstalk cancellation envelopes 72 where the current value at the time when the trigger signal to be determined is input is the maximum. More specifically, the determination of whether to perform crosstalk cancellation is made by comparing the crosstalk cancellation level with the level of the trigger signal to be determined. The crosstalk cancellation level is obtained by multiplying the current value (i.e., the time when the trigger signal to be determined is input) in the crosstalk cancellation envelope 72 used for determination by the cancellation rate specified for the hitting surface 20a or the hitting surface 21a which is the output source of the trigger signal to be determined. If the former is greater than the latter, it is determined that crosstalk cancellation is performed on the trigger signal to be determined. On the other hand, if the former is less than the latter, it is determined that crosstalk cancellation is not performed on the trigger signal to be determined.

[0072] The "cancellation rate" is a value obtained by dividing the crosstalk cancellation setting value set for each of the hitting surfaces 20a and 21a by 100. That is, when the crosstalk cancellation setting value is set to A, the cancellation rate is represented by A / 100. When determining whether to perform crosstalk cancellation, the crosstalk cancellation setting value set for the hitting surface 20a or the hitting surface 21a which is the output source of the trigger signal to be determined is used as the value A (crosstalk cancellation setting value).

[0073] Furthermore, the larger the crosstalk cancellation setting value, the more difficult it is to perform crosstalk cancellation. At the time of product shipment, the initial value of the crosstalk cancellation setting value is stored in an area (not shown) of a flash memory (not shown) or the ROM 42. The crosstalk cancellation setting value in the flash memory is configured to be changeable for each of the hitting surfaces 20a and 21a according to the needs of the user.

[0074] Specifically, the method for determining crosstalk cancellation is as follows: among one or more generated crosstalk cancellation envelopes 72, when the maximum value of the current value at the time x2 when the trigger signal is input from the hitting surface 20a or the hitting surface 21a is y2, the level of the input trigger signal is compared with y2×(A / 100) which is the crosstalk cancellation level. (A / 100) is the cancellation rate specified for the hitting surface 20a or the hitting surface 21a which is the output source of the trigger signal. In this case, for example, if the level of the trigger signal (the trigger signal to be determined) input from the hitting surface 20a or the hitting surface 21a is L2 which is less than y2×(A / 100), it is determined that crosstalk cancellation is performed on the trigger signal. On the other hand, if the level of the trigger signal to be determined is L1 which is greater than y2×(A / 100), it is determined that crosstalk cancellation is not performed on the trigger signal, that is, it is the trigger signal of the pronunciation object.

[0075] Thus, when the crosstalk cancellation program of the control device 40 determines that the vibration generated on the hitting surface 21a is caused by crosstalk due to the vibration of the other hitting surface 20a by comparing the output value of the head vibration sensor 28 that detects the vibration of, for example, one of the two hitting surfaces 20a and 21a, i.e., the hitting surface 21a, with the output value of the head vibration sensor 28 that detects the vibration of the other hitting surface 20a, it does not output a pronunciation instruction based on the vibration caused by crosstalk. Accordingly, even if the head vibration sensor 28 on the hitting surface 21a detects the vibration of the non-hit hitting surface 21a when the hitting surface 20a is struck, the pronunciation of the musical tone accompanying the detection can be prevented.

[0076] In addition, for example, when calculating the hitting position on the hitting surface 20a based on the output value of the head vibration sensor 28 on the hitting surface 20a, the vibration component of the hitting surface 20a caused by crosstalk due to the vibration of the hitting surface 21a can also be removed according to the crosstalk amount by comparing the output value of the head vibration sensor 28 on the hitting surface 20a side with the output value of the head vibration sensor 28 on the hitting surface 21a side. Thereby, the calculation accuracy of the hitting position on the hitting surface 20a can be improved.

[0077] Furthermore, similarly, the component of the output value of the rim vibration sensor 32 on the hitting surface 20a side caused by crosstalk due to the vibration of the hitting surface 21a can also be calculated by comparing the output value of the rim vibration sensor 32 on the hitting surface 20a side with the output value of the rim vibration sensor 32 on the hitting surface 21a side. When calculating the hitting position on the hitting surface 20a based on the output value of the rim vibration sensor 32 on the hitting surface 20a, the calculation accuracy of the hitting position on the hitting surface 20a can be improved by removing the component of the output value of the rim vibration sensor 32 on the hitting surface 20a side caused by crosstalk due to the vibration of the hitting surface 21a according to the crosstalk amount.

[0078] Return Figure 3 Explanation is as follows. The control device 40 has various data, memories, and flags for each of the hitting surfaces 20a and 21a, and performs regular processing of the control program 42a for each of the hitting surfaces 20a and 21a. The data, processing, etc. for each of the hitting surfaces 20a and 21a are the same. Therefore, hereinafter, the data, processing, etc. related to the hitting surface 20a will be described, and the description of the data, processing, etc. related to the hitting surface 21a will be omitted.

[0079] For Figure 8In the impact detection process, the impact position is detected. In the weighting coefficient data 42b stored in the ROM 42, there are a weighting coefficient W1, a weighting coefficient W2, a weighting coefficient W3, and a weighting coefficient b. The weighting coefficient W1, the weighting coefficient W2, the weighting coefficient W3, and the weighting coefficient b are coefficients representing the importance of respective characteristic quantities X1, characteristic quantity X2, and characteristic quantity X3 that vary according to the impact position on the striking surface 20a. In the impact detection process, the sum of the products of the respective corresponding characteristic quantities X1, characteristic quantity X2, and characteristic quantity X3 and the weighting coefficients W1, weighting coefficient W2, and weighting coefficient W3 is added to the weighting coefficient b as a constant term to calculate the imaginary edge degree A. That is, the imaginary edge degree A is represented by the formula "A = W1×X1 + W2×X2 + W3×X3 + b".

[0080] By substituting the imaginary edge degree A into a standard sigmoid function, the edge degree E represented between 0 and 1 is calculated. That is, in the case where the exponential function with the Napier constant as the base and x as the variable is expressed as exp(x), the edge degree E is represented by the formula "E = 1 / (1 + exp(-A))". The edge degree E is a value set to be 0 when the radial center of the striking surface 20a is struck and 1 when the outermost side in the radial direction of the striking surface 20a is struck.

[0081] The weighting coefficient W1, the weighting coefficient W2, the weighting coefficient W3, and the weighting coefficient b used in the calculation of the edge degree E are calculated by supervised learning of machine learning for each product design of the electronic percussion instrument 1 and stored as fixed values in the weighting coefficient data 42b at the time of product shipment. As a specific machine learning method, first, data of the respective characteristic quantities X1, characteristic quantity X2, and characteristic quantity X3 when the vicinity of the radial center of the striking surface 20a (range within 30% from the radial center) is struck are acquired, and the edge degree E to be output when these data are input is set to 0. In addition, data of the respective characteristic quantities X1, characteristic quantity X2, and characteristic quantity X3 when the vicinity of the outermost side in the radial direction of the striking surface 20a (range within 80% or more from the radial center) is struck are acquired, and the edge degree E to be output when these data are input is set to 1. By performing machine learning using these input-output data, the weighting coefficient W1, the weighting coefficient W2, the weighting coefficient W3, and the weighting coefficient b are calculated.

[0082] Refer to Figure 5 of (a) to Figure 5 of (c) to explain the respective characteristic quantities X1, characteristic quantity X2, and characteristic quantity X3. Figure 5The (a) of is an output value-time graph of the output waveform of the pressure-sensitive sensor 24. The vertical axis represents the output value of the pressure-sensitive sensor 24, and the horizontal axis represents time. Moreover, the greater the pressure applied to the pressure-sensitive sensor 24, the smaller the output value of the pressure-sensitive sensor 24. In the present embodiment, the maximum value of the output value of the pressure-sensitive sensor 24 is 1024.

[0083] In a state where the striking surface 20a is not struck or pressed, pressure is applied to the pressure-sensitive sensor 24 from the compressed elastic body 26. Therefore, the output value of the pressure-sensitive sensor 24 exists near the reference value B1 at a position lower than the maximum value 1024. When the striking surface 20a is struck or pressed, the output value of the pressure-sensitive sensor 24 decreases and takes a peak value Pm. The value obtained by subtracting the peak value Pm from the reference value B1 before the striking surface 20a is struck or pressed is the pressure-sensitive peak characteristic quantity X2.

[0084] The closer the striking position of the striking surface 20a is to the central portion of the striking surface 20a, the greater the pressure-sensitive peak characteristic quantity X2, and the closer the striking position is to the peripheral portion of the striking surface 20a, the smaller the pressure-sensitive peak characteristic quantity X2. This is because the closer the striking position is to the central portion of the striking surface 20a, the easier it is for the striking surface 20a to flex downward, and the stronger the pressure applied to the pressure-sensitive sensor 24 from the striking surface 20a.

[0085] Figure 5 The (b) of is a voltage-time graph of the voltage waveform of the head vibration sensor 28. Figure 5 The (c) of is a voltage-time graph of the voltage waveform of the rim vibration sensor 32. In both cases, the vertical axis represents voltage and the horizontal axis represents time. The voltage waveform of the head vibration sensor 28 takes a negative voltage value (output value) when the striking surface 20a vibrates downward (toward the head vibration sensor 28 side). The greater the swing of the striking surface 20a, the greater the amplitude of the voltage waveform of the head vibration sensor 28. In addition, the greater the swing of the frame body 10, the greater the amplitude of the voltage waveform of the rim vibration sensor 32.

[0086] When the absolute value of the voltage value of the head vibration sensor 28 exceeds a specified striking threshold N1, the CPU 41 determines that the striking surface 20a has been struck. The maximum value of the absolute value of the voltage value of the head vibration sensor 28 within 5 milliseconds from the time when it is determined to have been struck is set as the peak value Pzhm. In addition, the maximum value of the absolute value of the voltage value (output value) of the rim vibration sensor 32 within 5 milliseconds from the time when it is determined to have been struck based on the voltage waveform of the head vibration sensor 28 is set as the peak value Pzrm.

[0087] The closer the hitting position is to the central portion of the hitting surface 20a, the easier it is for the hitting surface 20a to flex downward, and the larger the peak value Pzhm of the head vibration sensor 28. In addition, the vibration caused by hitting the hitting surface 20a is transmitted from the peripheral portion of the hitting surface 20a to the frame 10. Therefore, the closer the hitting position is to the central portion of the hitting surface 20a, the longer the vibration transmission distance from the hitting position to the rim vibration sensor 32 that detects the vibration of the frame 10, and the smaller the peak value Pzrm of the rim vibration sensor 32.

[0088] The value obtained by dividing the peak value Pzhm of the head vibration sensor 28 by the peak value Pzrm of the rim vibration sensor 32 and then multiplying by the user parameter stored in the adjustment value memory 43k described later is the peak ratio characteristic quantity X1. Based on the characteristics of the peak value Pzhm of the head vibration sensor 28 and the peak value Pzrm of the rim vibration sensor 32 described above, the closer the hitting position is to the central portion of the hitting surface 20a, the larger the peak ratio characteristic quantity X1, and the closer the hitting position is to the peripheral portion of the hitting surface 20a, the smaller the peak ratio characteristic quantity X1.

[0089] The distance of the initial half-wave in which the hitting surface 20a initially vibrates (takes a negative value) toward the head vibration sensor 28 in the voltage waveform of the head vibration sensor 28 based on the hitting of the hitting surface 20a is the distance characteristic quantity X3. That is, the so-called initial half-wave is the portion between two points where the voltage value becomes 0 before and after the position where it first intersects the hitting threshold N1 in the voltage waveform of the head vibration sensor 28. The closer the hitting position is to the central portion of the hitting surface 20a, the larger the distance characteristic quantity X3, and the closer the hitting position is to the peripheral portion of the hitting surface 20a, the smaller the distance characteristic quantity X3. This is because the vibration mode of the hitting surface 20a when hitting the central portion of the hitting surface 20a is different from the vibration mode of the hitting surface 20a when hitting the peripheral portion of the hitting surface 20a.

[0090] Return Figure 3 The RAM 43 is a memory that can rewrite and store various working data, flags, etc. when the CPU 41 executes programs such as the control program 42a. In the RAM 43, a head sensor value ring buffer 43a, a rim sensor value ring buffer 43b, a pressure-sensitive sensor value ring buffer 43c, a reference value calculation ring buffer 43d, an average value memory 43e, a reference value memory 43f, a hitting process flag 43g, a pressing-in flag 43h, a pressing-in value memory 43i, a characteristic quantity memory 43j, an adjustment value memory 43k, and an edge degree memory 43l are respectively provided.

[0091] The head sensor value ring buffer 43a is a buffer that stores the output values of the head vibration sensor 28 for the past 5 milliseconds after analog / digital (A / D) conversion. The rim sensor value ring buffer 43b is a buffer that stores the output values of the rim vibration sensor 32 for the past 5 milliseconds after A / D conversion. The pressure-sensitive sensor value ring buffer 43c is a buffer that stores the output values of the pressure-sensitive sensor 24 for the past 5 milliseconds after A / D conversion.

[0092] The head sensor value ring buffer 43a and the rim sensor value ring buffer 43b are initialized by filling them with "0" immediately after the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. The pressure-sensitive sensor value ring buffer 43c is initialized by filling it with an invalid value immediately after the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. The invalid value is a value that cannot be obtained due to the structure of the pressure-sensitive sensor 24. In the present embodiment, the value 1025, which is greater than the maximum value 1024 of the pressure-sensitive sensor 24, is set as the invalid value and stored in the pressure-sensitive sensor value ring buffer 43c during initialization.

[0093] In Figure 6 the periodic process of (b), the sensor values (output values) of the pressure-sensitive sensor 24, the head vibration sensor 28, and the rim vibration sensor 32 (hereinafter referred to as "each sensor 24, sensor 28, sensor 32") at the time point when the periodic process is executed are added to the corresponding head sensor value ring buffer 43a, rim sensor value ring buffer 43b, and pressure-sensitive sensor value ring buffer 43c (hereinafter referred to as "each ring buffer 43a, ring buffer 43b, ring buffer 43c") ( Figure 6 of (b), S10).

[0094] In each of the ring buffers 43a, 43b, and 43c, there is a memory that stores 50 output values of each of the sensors 24, 28, and 32, and a memory that stores which of the 50 output values is the latest. This is because the periodic process of Figure 7 described later is executed every 100 microseconds = 0.1 milliseconds, and the output values for the past 5 milliseconds are stored.

[0095] First, each of the ring buffers 43a, 43b, and 43c stores the acquired respective output values in the order of No.1 to No.50. Then, after each output value is stored at No.50, the output values are stored again in sequence starting from No.1. Thus, a state is achieved where the output values of the maximum past 5 milliseconds are stored in each of the ring buffers 43a, 43b, and 43c. Using the values of the respective ring buffers 43a, 43b, and 43c, the peak value Pzhm of the head vibration sensor 28, the peak value Pzrm of the rim vibration sensor 32, the peak value Pm of the pressure-sensitive sensor 24, and the pitch characteristic quantity X3, which is the pitch of the initial half-wave of the head vibration sensor 28, are obtained.

[0096] The reference value calculation ring buffer 43d is a buffer that stores eight output values of the pressure-sensitive sensor 24 acquired basically every 1 second for calculating the reference value of the pressure-sensitive sensor 24. Furthermore, the output value of the pressure-sensitive sensor 24 stored in the reference value calculation ring buffer 43d is different from the output value of the pressure-sensitive sensor 24 stored in the pressure-sensitive sensor value ring buffer 43c. The output value of the pressure-sensitive sensor 24 stored in the reference value calculation ring buffer 43d is a value obtained by averaging the past 0.8 millisecond amount of the output values of the pressure-sensitive sensor 24 stored in the pressure-sensitive sensor value ring buffer 43c every 0.1 millisecond in the periodic process. Hereinafter, the output value of the pressure-sensitive sensor 24 stored in the reference value calculation ring buffer 43d is referred to as the average output value of the pressure-sensitive sensor 24. The average output value of the pressure-sensitive sensor 24 can be said to be an output value from which the electrical noise of the pressure-sensitive sensor 24 has been removed.

[0097] The reference value calculation ring buffer 43d is initialized by filling it with "0" immediately after the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. Then, in the periodic process of (b) of Figure 6 , when the striking surface 20a is not pressed and the press-in mark 43h is off, and more than 1 second has elapsed since the last update or more than 10 seconds have elapsed since the striking surface 20a was struck, the average output value (the value of the average value memory 43e) of the pressure-sensitive sensor 24 updated during the periodic process is added to the reference value calculation ring buffer 43d ( Figure 6 (b) of

[0098] In the reference value calculation ring buffer 43d, there is a memory that stores eight average output values of the pressure-sensitive sensor 24. First, the reference value calculation ring buffer 43d stores the acquired average output values in the order of No.1 to No.8. Then, after the average output value is stored at No.8, the average output values are stored again in sequence starting from No.1.

[0099] The average value memory 43e is a memory that stores the average output value of the pressure-sensitive sensor 24. The value of the average value memory 43e is immediately initialized to "0" when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. Then, in the periodic process of (b) of Figure 6 , after storing the output value of the new pressure-sensitive sensor 24 in the pressure-sensitive sensor value ring buffer 43c every 0.1 millisecond, the average output value of the pressure-sensitive sensor 24 for the past 0.8 millisecond is averaged to calculate the average output value of the pressure-sensitive sensor 24, and the average output value of the pressure-sensitive sensor 24 is stored in the average value memory 43e ( Figure 6 of (b), S12).

[0100] The reference value memory 43f is a memory that stores the reference value of the pressure-sensitive sensor 24. The value of the reference value memory 43f is immediately initialized with an invalid value when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. An invalid value means a value that cannot be obtained structurally by the pressure-sensitive sensor 24. Then, in the periodic process of (b) of Figure 6 , after storing the average output value of the new pressure-sensitive sensor 24 in the reference value calculation ring buffer 43d, the eight values of the reference value calculation ring buffer 43d are averaged to calculate the reference value of the pressure-sensitive sensor 24, and the reference value is saved in the reference value memory 43f ( Figure 6 of (b), S22).

[0101] As shown in (a) of Figure 5 , the output value of the pressure-sensitive sensor 24 sometimes changes before and after the striking surface 20a is struck or pressed. This is because the deformation mode of the elastic body 26 sandwiched between the pressure-sensitive sensor 24 and the striking surface 20a or the return mode of the striking surface 20a changes. In addition, the output value of the pressure-sensitive sensor 24 also changes according to the tension applied to the head 20 or the external air temperature, etc.

[0102] Therefore, in the periodic process of (b) of Figure 6 , it is necessary to update the reference value of the pressure-sensitive sensor 24 at each specified update time. For example, specifically, if it is described using (a) of Figure 5 , before the striking surface 20a is struck, the output value of the pressure-sensitive sensor 24 follows the reference value B1, and after the striking surface 20a is struck, the output value of the pressure-sensitive sensor 24 stabilizes at a value lower than the reference value B1. Therefore, the reference value B2 is set at the position followed by the newly stabilized output value of the pressure-sensitive sensor 24.

[0103] Furthermore, the so-called stable output value of the pressure-sensitive sensor 24 means that the output value of the pressure-sensitive sensor 24 is approximately constant. Specifically, the change rate of the output value of the pressure-sensitive sensor 24 is within 5%. Here, from the state of strongly pressing the striking surface 20a and instantly releasing the pressing until the output value of the pressure-sensitive sensor 24 is the lowest (until it stops changing), the stabilization time from the release of the pressing until the output value of the pressure-sensitive sensor 24 stabilizes is about 10 seconds in the electronic percussion instrument 1 of the present embodiment.

[0104] Return Figure 3 。The strike processing flag 43g is a flag indicating the strike detection process based on the strike on the striking surface 20a. The strike processing flag 43g is set to indicate off, which means not in the strike detection process, immediately when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) is executed. Figure 6 In the periodic process of (b), when the absolute value of the latest value (the current output value of the head vibration sensor 28) in the head sensor value ring buffer 43a exceeds the strike threshold N1, the strike processing flag 43g is set to on ( Figure 6 (b) of, S26). In addition, in the periodic process when the strike detection ends, the strike processing flag 43g is set to off ( Figure 6 (, S53). Figure 8

[0105] The depression flag 43h is a flag indicating that the striking surface 20a is depressed. The depression flag 43h is set to indicate off, which means the striking surface 20a is not depressed, immediately when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) is executed. Figure 6 In the depression detection process executed in the periodic process of (b) of Figure 6 when the difference between the reference value and the average output value of the pressure-sensitive sensor 24 is greater than the depression threshold N2 and lasts for 10 milliseconds during the period when the depression flag 43h is off, the depression flag 43h is set to on ( Figure 7 (, S40). In addition, when the difference between the reference value and the average output value of the pressure-sensitive sensor 24 is less than or equal to the depression threshold N2 and lasts for 1 millisecond during the period when the depression flag 43h is on, the depression flag 43h is set to off ( Figure 7 (, S47). Figure 7

[0106] The depression value memory 43i is a memory that stores the depression value, which is the amount of change in the output value of the pressure-sensitive sensor 24 caused by the depression of the striking surface 20a. The value of the depression value memory 43i is immediately initialized to "0" when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) is executed. Figure 6 In Figure 7In the pressing detection process, when the difference between the reference value and the average output value of the pressure-sensitive sensor 24 is greater than the pressing threshold N2, and the value obtained by subtracting the pressing threshold N2 from the reference value and then subtracting the average output value of the pressure-sensitive sensor 24 is greater than the movable threshold N3, 127, which is the maximum value of the pressing value, is stored in the pressing value memory 43i( Figure 7 , S35). Further, when the difference between the reference value and the average output value of the pressure-sensitive sensor 24 is greater than the pressing threshold N2, and the value obtained by subtracting the pressing threshold N2 from the reference value and then subtracting the average output value of the pressure-sensitive sensor 24 is less than or equal to the movable threshold N3, the pressing value is calculated by multiplying the value obtained by subtracting the pressing threshold N2 from the reference value and then subtracting the average output value of the pressure-sensitive sensor 24 by 127 and dividing the result by the movable threshold N3, and the pressing value is stored in the pressing value memory 43i( Figure 7 , S36).

[0107] The movable threshold N3 is the range to be ensured as the movable amount of the pressing value. When the value obtained by subtracting the pressing threshold N2 from the reference value and then subtracting the average output value of the pressure-sensitive sensor 24 is less than or equal to the movable threshold N3, the pressing value stored in the pressing value memory 43i is calculated by multiplying by 127. Thus, it can be divided into 127 stages between the value obtained by subtracting the pressing threshold N2 from the reference value and the average output value of the pressure-sensitive sensor 24 that takes the maximum value of the pressing value based on the movable threshold N3. Thus, the pressing value can be output to the sound source 45 or the like at 127 levels of electric potential.

[0108] The feature amount memory 43j is a memory that stores each of the feature amounts X1, the feature amount X2, and the feature amount X3. The value of the feature amount memory 43j is initialized to "0" immediately when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. In the percussion detection process of Figure 8 that starts immediately after the striking surface 20a is struck, each of the feature amounts X1, the feature amount X2, and the feature amount X3 is calculated and stored in the feature amount memory 43j( Figure 8 , S55, S56, S57).

[0109] The adjustment value memory 43k is a memory that stores the user parameter used in the calculation of the peak ratio feature amount X1. The value of the adjustment value memory 43k is initialized to "1" immediately when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. The user parameter of the adjustment value memory 43k is changed by operating the operating member 15. Further, the flash memory that is not initialized immediately when the power of the electronic percussion instrument 1 is turned on or after the initialization process of (a) of Figure 6 is executed can also be provided in the control device 40, and the adjustment value memory 43k is provided in the flash memory.

[0110] If the user parameter of the adjustment value memory 43k is greater than 1, the value of the peak ratio feature quantity X1 becomes larger, and the edge degree E is likely to approach 0, so that it is possible to easily emit a musical tone when the central portion of the striking surface 20a is struck. If the value of the adjustment value memory 43k is less than 1, the value of the peak ratio feature quantity X1 becomes smaller, and the edge degree E is likely to approach 1, so that it is possible to easily emit a musical tone when the peripheral portion of the striking surface 20a is struck.

[0111] The edge degree memory 43l is a memory that stores the edge degree E indicating the striking position. The value of the edge degree memory 43l is immediately initialized to "0" when the power of the electronic percussion instrument 1 is turned on and after the initialization process of (a) of Figure 6 is executed. In the strike detection process of Figure 8 that starts immediately after the striking surface 20a is struck, the edge degree E is calculated using the respective feature quantities X1, X2, X3 stored in the feature quantity memory 43j and the weighting coefficients W1, W2, W3, b stored in the weighting coefficient data 42b, and the edge degree E is stored in the edge degree memory 43l ( Figure 8 , S58, S59).

[0112] Refer to Figure 6 to describe the initialization process executed by the CPU 41 of the electronic percussion instrument 1 in (a). Figure 6 The (a) of

[0113] is a flowchart of the initialization process. The initialization process is executed immediately after the power of the electronic percussion instrument 1 is turned on, and the values (variables) of each memory and the flags on the RAM 43 are initialized (S1). In particular, in the initialization process, the pressure-sensitive sensor value ring buffer 43c is filled with invalid values, and the invalid values are stored in the reference value memory 43f. In addition, in the initialization process, the reference value update timer T1, the depression value update timer T2, the depression switching timer T3, and the strike timer T4 described later are initialized to "0 seconds". Figure 8 Next, refer to (b) to Figure 7 of 6 to describe the periodic process executed by the CPU 41 of the electronic percussion instrument 1. In the periodic process, the output values of the respective sensors 24, 28, 32 at the time when the periodic process is executed, or the update of the reference value, the depression detection process ( Figure 8 ), the strike detection process (

[0114] Figure 6 ) are executed, and the instruction for sounding a musical tone is given. The periodic process is repeated every 0.1 millisecond by an interval interrupt process every 0.1 millisecond.The flowchart of (b) is for periodic processing. In the periodic processing, first, the sensor values (output values) of each of the sensors 24, 28, and 32 are acquired and respectively appended to each of the ring buffers 43a, 43b, and 43c (S10). Since the periodic processing is executed every 0.1 milliseconds, the values of each of the ring buffers 43a, 43b, and 43c are updated every 0.1 milliseconds.

[0115] After the processing of S10, it is confirmed whether eight or more (the amount for the past 0.8 milliseconds) valid values are stored in the pressure-sensitive sensor value ring buffer 43c (S11). Furthermore, a valid value is a value from 0 to 1024 that the pressure-sensitive sensor 24 can acquire. When eight or more valid values are not stored in the pressure-sensitive sensor value ring buffer 43c (S11: No), the periodic processing ends and waits until eight or more valid values are stored in the pressure-sensitive sensor value ring buffer 43c, that is, until 0.8 milliseconds or more have elapsed since the initialization processing.

[0116] When eight or more valid values are stored in the pressure-sensitive sensor value ring buffer 43c (S11: Yes), referring to the values of the pressure-sensitive sensor value ring buffer 43c, the values of the pressure-sensitive sensor 24 for the amount of 0.8 milliseconds are averaged by tracing back from the current periodic processing, the average output value of the pressure-sensitive sensor 24 is calculated, and is stored in the average value memory 43e (S12). Thereby, the output value (average output value) of the pressure-sensitive sensor 24 from which electrical noise has been removed is obtained.

[0117] After the processing of S12, it is confirmed whether the value of the reference value memory 43f is a valid value (S13). A valid value is a value from 0 to 1024 that the pressure-sensitive sensor 24 can acquire. In the initialization processing, an invalid value is stored in the reference value memory 43f. Therefore, in the first processing of S13 after the initialization processing, the value of the reference value memory 43f is not a valid value (S13: No). In this case, the average output value of the average value memory 43e is filled in the reference value calculation ring buffer 43d (S14). Thereafter, the average output value of the average value memory 43e is stored in the reference value memory 43f in such a manner that the reference value obtained by averaging the values of the reference value calculation ring buffer 43d is stored in the reference value memory 43f (S15). Subsequently, 1 second is set in the reference value update timer T1 indicating the time until the value of the reference value memory 43f is updated next (S16).

[0118] In the process of S13, when the value in the reference value memory 43f is a valid value (S13: Yes), the depression detection process (S17) is executed. In the depression detection process, the depression flag 43h is set to ON when the hitting surface 20a is pressed, and the depression flag 43h is set to OFF when the hitting surface 20a is not pressed. For details, refer to Figure 7 described later.

[0119] After the process of S17, it is confirmed whether the hitting process flag 43g indicating the start of the hitting detection process based on the hit on the hitting surface 20a is OFF (S18). When the hitting process flag 43g is OFF (S18: Yes), the absolute value of the latest value in the head sensor value ring buffer 43a is confirmed, that is, whether the absolute value of the output value of the head vibration sensor 28 at the start of the current periodic process is less than or equal to the hitting threshold N1 (S19). When the absolute value of the latest value in the head sensor value ring buffer 43a is less than or equal to the hitting threshold N1 (S19: Yes), the hitting surface 20a has not been hit, so it is confirmed whether the depression flag 43h indicating that the hitting surface 20a is pressed is OFF (S20). Figure 8

[0120] When the depression flag 43h is OFF (S20: Yes), 0.1 milliseconds is subtracted from the reference value update timer T1 (S21). After the process of S21, it is confirmed whether the reference value update timer T1 becomes 0 seconds or less (S22). When the reference value update timer T1 is greater than 0 seconds (S22: No), after updating the value in the reference value memory 43f, the timing for the next update of the value has not arrived, so the periodic process ends.

[0121] When the reference value update timer T1 becomes 0 seconds or less (S22: Yes), 1 second is set in the reference value update timer T1 (S23), and the average output value of the pressure-sensitive sensor 24 stored in the average value memory 43e is added to the reference value calculation ring buffer 43d (S24). Subsequently, the average value of the total eight average output values of the pressure-sensitive sensors 24 stored in the reference value calculation ring buffer 43d is calculated to obtain the reference value, and the reference value is stored in the reference value memory 43f (S25), and the periodic process ends.

[0122] In this way, basically every 1 second, the average output value of the pressure-sensitive sensor 24 is added to the reference value calculation ring buffer 43d, and after the addition, the value in the reference value calculation ring buffer 43d is averaged to calculate the reference value. Therefore, the reference value stored in the reference value memory 43f is basically updated at an update time of every 1 second. In addition, the average output values of the eight pressure-sensitive sensors 24 that are basically updated every 1 second are averaged. Therefore, the output values of the pressure-sensitive sensor 24 obtained during the sampling time of 8 seconds are averaged to calculate the reference value.​

[0123] When the mark 43h is turned on during the process of S20 (S20: No), the hitting surface 20a is pressed, so 1 second is set in the reference value update timer T1 (S29). From the release of the pressing of the hitting surface 20a until 1 second has elapsed, the update of the reference value in the reference value memory 43f is prohibited. By prohibiting the update of the reference value during the period when the hitting surface 20a is pressed, it is possible to prevent the depression value based on the change amount of the average output value of the pressure-sensitive sensor 24 with respect to the reference value from changing due to the update of the reference value. As a result, an appropriate depression value can be obtained. Furthermore, by prohibiting the update of the reference value after the pressing of the hitting surface 20a is released, the reference value in the reference value memory 43f can be updated without using the average output value of the pressure-sensitive sensor 24 that easily changes according to the vibration of the hitting surface 20a accompanying the release of the pressing, so the reference value can be set appropriately.

[0124] In the process of S19, when the absolute value of the latest value in the head sensor value ring buffer 43a is greater than the hitting threshold N1 (S19: Yes), the hitting surface 20a is hit, so the hitting process flag 43g is turned on (S26). Then, 10 seconds is set in the reference value update timer T1 (S27), and the hit detection process is executed (S28), and the periodic process ends. Regarding the hit detection process, refer to Figure 8 which will be described later. In addition, in the process of S18, when the hitting process flag 43g is on (S18: No), the hit detection process is executed (S28), and the periodic process ends.

[0125] In this way, from the time when the hitting surface 20a is hit until 10 seconds, which is the stable time until the vibration of the hitting surface 20a is sufficiently attenuated, no new average output value of the pressure-sensitive sensor 24 is added to the reference value calculation ring buffer 43d, and the update of the reference value in the reference value memory 43f is prohibited. As a result, the reference value in the reference value memory 43f can be updated without using the average output value of the pressure-sensitive sensor 24 that easily changes according to the hitting surface 20a that vibrates greatly after being hit, so the reference value can be set appropriately.

[0126] Next, refer to Figure 7 to Figure 6 explain the depression detection process (S17) executed in the periodic process of (b). The depression detection process determines whether the hitting surface 20a is pressed, and calculates the depression value when the hitting surface 20a is pressed. More specifically, in the depression detection process (depression detection component), the pressing of the hitting surface 20a (the presence or absence of pressing or the depression value) is detected based on the difference between the average output value of the pressure-sensitive sensor 24 and the reference value.

[0127] First, it is checked whether the difference obtained by subtracting the average output value of the average value memory 43e from the reference value of the reference value memory 43f is greater than the pressing threshold N2 (S30). When the difference obtained by subtracting the average output value of the average value memory 43e from the reference value of the reference value memory 43f is greater than the pressing threshold N2 (S30: Yes), there is a possibility that the hitting surface 20a is pressed. Therefore, the processes from S31 to S36 are executed, and the pressing value is calculated.

[0128] In the process of S31, 0.1 milliseconds is added to the pressing value update timer T2 that is initialized to 0 seconds through initialization processing or the like. The pressing value update timer T2 represents the time until the next update of the pressing value during the period when it is determined that there is a possibility that the hitting surface 20a is pressed (S30: Yes). After the process of S31, it is checked whether the pressing value update timer T2 is 1 millisecond (S32). When the pressing value update timer T2 is less than 1 millisecond (S32: No), the timing for the next update of the pressing value has not arrived. Therefore, the processes from S33 to S36 are skipped.

[0129] When the pressing value update timer T2 is 1 millisecond (S32: Yes), it is highly likely that the decrease in the average output value of the average value memory 43e is caused by the pressing of the hitting surface 20a, and the timing for updating the pressing value has arrived. Therefore, first, the pressing value update timer T2 is initialized to 0 seconds in order to update the next pressing value (S33). After the process of S33, it is checked whether the value obtained by subtracting the pressing threshold N2 and the average output value of the average value memory 43e from the reference value of the reference value memory 43f is greater than the movable threshold N3 (S34).

[0130] When the value obtained by subtracting the pressing threshold N2 and the average output value of the average value memory 43e from the reference value of the reference value memory 43f is greater than the movable threshold N3 (S34: Yes), the hitting surface 20a is pressed strongly enough. Therefore, 127, which is the maximum value of the pressing value, is stored in the pressing value memory 43i (S35).

[0131] On the other hand, when the value obtained by subtracting the pressing threshold N2 and the average output value of the average value memory 43e from the reference value of the reference value memory 43f is equal to or less than the movable threshold N3 (S34: No), in order to represent the pressing value in 127 levels, the pressing value represented by the formula "(reference value of the reference value memory 43f - pressing threshold N2 - average output value of the average value memory 43e) × 127 / movable threshold N3" is stored in the pressing value memory 43i (S36). Thus, the control of the musical tone corresponding to 127 levels can be performed.

[0132] In the process of S30, when there is a possibility that the hitting surface 20a is pressed based on the decrease in the average output value of the average value memory 43e (S30: Yes), after performing the processes of S31 to S36, it is confirmed whether the depression mark 43h indicating that the hitting surface 20a is pressed is off (S37). When the depression mark 43h is on (S37: No), there is no need to switch the depression mark 43h, so the depression switching timer T3 is initialized to 0 seconds (S42), and the depression detection process ends.

[0133] When the depression mark 43h is off (S37: Yes), in order to determine whether the decrease in the average output value of the average value memory 43e is caused by pressing or hitting, first, 0.1 milliseconds is added to the depression switching timer T3 that has been initialized to 0 seconds through initialization processing or the like (S38). The depression switching timer T3 represents the time until the depression mark 43h is switched along with the change in the average output value of the average value memory 43e.

[0134] After the process of S38, it is confirmed whether the depression switching timer T3 is 10 milliseconds (S39). When the depression switching timer T3 is less than 10 milliseconds (S39: No), there is a possibility that the decrease in the average output value of the average value memory 43e is caused by hitting, so the depression detection process ends.

[0135] When the depression switching timer T3 is 10 milliseconds (S39: Yes), the average output value of the average value memory 43e continues to decrease during the 10 - millisecond period. Therefore, it is determined that the decrease in the average output value is caused by pressing, the depression mark 43h is set to on (S40), the depression switching timer T3 is initialized to 0 seconds (S41), and the depression detection process ends.

[0136] In the process of S30, when the difference obtained by subtracting the average output value of the average value memory 43e from the reference value of the reference value memory 43f is equal to or less than the pressing threshold N2 (S30: No), there is a possibility that the hitting surface 20a is not pressed. Therefore, the depression value update timer T2 is initialized to 0 seconds (S43). Assuming that there is a possibility that the hitting surface 20a was pressed through the previous periodic processing (S30: Yes), when starting to count time using the depression value update timer T2, the decrease in the average output value of the average value memory 43e during the periodic processing until starting to count time using the depression value update timer T2 is not caused by pressing the hitting surface 20a, and there is a high possibility that it is caused by hitting the hitting surface 20a. Therefore, the depression value update timer T2 is initialized without calculating the depression value.

[0137] After the process of S43, it is confirmed whether the depression mark 43h is on (S44). When there is a possibility that the hitting surface 20a is not pressed (S30: No), and the depression mark 43h is off (S44: No), there is no need to switch the depression mark 43h. Therefore, the depression switching timer T3 is initialized to 0 seconds (S42), and the depression detection process ends.

[0138] Furthermore, it is assumed that there is a possibility that the hitting surface 20a has been pressed through the previous periodic processes (S30: Yes). When starting to time using the depression switching timer T3 to switch the depression mark 43h, the decrease in the average output value of the average value memory 43e during the periodic processes until starting to time using the depression switching timer T3 is not caused by the pressing of the hitting surface 20a, and is highly likely to be caused by the hitting of the hitting surface 20a. Therefore, the depression switching timer T3 is initialized in preparation for the next switching of the depression mark 43h.

[0139] In the process of S44, when the depression mark 43h is on (S44: Yes), in order to determine whether the increase in the average output value of the average value memory 43e is caused by the release of the press, first, 0.1 milliseconds is added to the depression switching timer T3 (S45).

[0140] After the process of S45, it is confirmed whether the depression switching timer T3 is 1 millisecond (S46). When the depression switching timer T3 is less than 1 millisecond (S46: No), there is a possibility that the increase in the average output value of the average value memory 43e is caused by the hitting of the hitting surface 20a or noise. Therefore, the depression detection process ends.

[0141] Furthermore, in the periodic processes after starting to time using the depression switching timer T3 through the processes of S45 and S46, when the difference obtained by subtracting the average output value of the average value memory 43e from the reference value of the reference value memory 43f is greater than the pressing threshold N2 before the depression switching timer T3 becomes 1 millisecond (S30: Yes), in the process of S42, the depression switching timer T3 is initialized to 0 seconds, and the depression detection process ends.

[0142] In the process of S46, when the depression switching timer T3 is 1 millisecond (S46: Yes), the average output value of the average value memory 43e continues to rise during 1 millisecond. Therefore, it is determined that the increase in the average output value is caused by the release of the press, the depression mark 43h is set to off (S47), the depression switching timer T3 is initialized to 0 seconds (S48), and the depression detection process ends.

[0143] As described above, in the pressing detection process, when switching the pressing flag 43h from OFF to ON, a wait of 10 milliseconds is provided, and when switching the pressing flag 43h from ON to OFF, a wait of 1 millisecond is provided. Even when the striking surface 20a is struck while the striking surface 20a is being pressed, it is difficult for the striking surface 20a to vibrate. Therefore, it is difficult for the average output value of the pressure sensor 24 to increase, and the vibration of the striking surface 20a decays prematurely. On the contrary, when the striking surface 20a is struck while the striking surface 20a is not being pressed, the striking surface 20a easily vibrates, and the time until the vibration sufficiently decays is long. Thus, the responsiveness can be improved by shortening the waiting time when switching the pressing flag 43h from conduction to disconnection, and it is possible to surely determine that the striking surface 20a is being pressed by lengthening the waiting time when switching the pressing flag 43h from disconnection to connection.

[0144] Next, with reference to Figure 8 to Figure 6 the strike detection process (S28) performed in the periodic process of (b) will be described. The strike detection process is a process executed based on a strike on the striking surface 20a, calculates the strike position on the striking surface 20a, and outputs an instruction to generate a musical tone.

[0145] First, the strike detection process adds 0.1 millisecond to the strike timer T4, which has been initialized to 0 seconds through initialization processing or the like (S50). The strike timer T4 represents the elapsed time after the absolute value of the latest value of the head sensor value ring buffer 43a exceeds the strike threshold N1 ( Figure 6 of (b), S20: Yes).

[0146] After the process of S50, it is confirmed whether the strike timer T4 is 5 milliseconds (S51). When the strike timer T4 is less than 5 milliseconds (S51: No), the time required to obtain the peaks of the respective sensors 24, 28, and 32 has not elapsed. Therefore, the processes of S52 to S60 are skipped, and the strike detection process ends.

[0147] In the process of S51, when the strike timer T4 is 5 milliseconds (S51: Yes), the time required to obtain the peaks of the respective sensors 24, 28, and 32 has elapsed. Therefore, first, in preparation for when the striking surface 20a is struck again in the next strike detection process, the strike timer T4 is initialized to 0 seconds (S52), and the strike process flag 43g is set to OFF (S53).

[0148] After the process of S53, the peak value Pzhm of the head vibration sensor 28, the peak value Pzrm of the rim vibration sensor 32, and the peak value Pm of the pressure-sensitive sensor 24 within 5 milliseconds from the values of each of the ring buffers 43a, 43b, and 43c are acquired (S54, peak value acquisition component). Subsequently, the peak ratio feature quantity X1 is calculated based on the formula "peak ratio feature quantity X1 = peak value Pzhm × user parameter of the adjustment value memory 43k / peak value Pzrm" and stored in the feature quantity memory 43j (S55).

[0149] After the process of S55, the pressure-sensitive peak feature quantity X2 is calculated based on the formula "pressure-sensitive peak feature quantity X2 = reference value of the reference value memory 43f - peak value Pm" and stored in the feature quantity memory 43j (S56). Thereafter, the pitch of the initial half-wave of the head vibration sensor 28 is calculated based on the value of the head sensor value ring buffer 43a as the pitch feature quantity X3 and stored in the feature quantity memory 43j (S57, pitch acquisition component).

[0150] After the process of S57, using each of the feature quantities X1, feature quantity X2, feature quantity X3 stored in the feature quantity memory 43j and the weighting coefficients W1, W2, W3, and the bias b stored in the weighting coefficient data 42b, the imaginary sharpness A is calculated according to the formula "A = W1 × X1 + W2 × X2 + W3 × X3 + b" (S58). Subsequently, the imaginary sharpness A is substituted into the standard S-shaped function to calculate the sharpness E represented by "E = 1 / (1 + exp(-A))" and stored in the sharpness memory 43l (S59). The processes up to S54 to S59 are a position calculation component (position calculation step) for calculating the hitting position based on the output values of the respective sensors 24, sensor 28, and sensor 32.

[0151] After the process of S59, an instruction for sounding a musical tone corresponding to the sharpness E of the sharpness memory 43l, the state of the depression flag 43h, the depression value of the depression value memory 43i, and the values of each of the ring buffers 43a, 43b, and 43c is output to the sound source 45 (S60), and the hitting detection process is ended.

[0152] The sound source 45 calculates the intensity of the hit on the hitting surface 20a or the vibration state of the hitting surface 20a based on the values of each of the ring buffers 43a, 43b, and 43c and outputs a musical tone signal corresponding to the intensity of the hit or the vibration state. In addition, when the depression flag 43h is off, the sound source 45 outputs a normal musical tone signal indicating that the hitting surface 20a is not depressed. On the other hand, when the depression flag 43h is on, the sound source 45 outputs a musical tone signal such that the vibration of the hitting surface 20a decays in advance according to the depression value.

[0153] When the edge degree E is 0, the sound source 45 outputs a musical sound signal when the central part of the striking surface 20a is struck, and when the edge degree E is 1, the sound source 45 outputs a musical sound signal when the peripheral part of the striking surface 20a is struck. When the edge degree E is between 0 and 1, the sound source 45 outputs a musical sound signal such that the ratio of the magnitude from 0 to the edge degree E to the magnitude from the edge degree E to 1 is the same as the volume ratio of the musical sound when the central part is struck to the musical sound when the peripheral part is struck.

[0154] In the electronic percussion instrument (musical sound generation device) 1 as described above, the elastic body 26 is compressed between the striking surface 20a and the pressure-sensitive sensor 24. Therefore, there is no clearance between the striking surface 20a and the pressure-sensitive sensor 24, and thus, even if the striking surface 20a is not strongly pressed, the output value of the pressure-sensitive sensor 24 can be changed. Due to the absence of clearance, even if the striking surface 20a is not pressed or struck, the output value of the pressure-sensitive sensor 24 does not fluctuate. Therefore, when the reference value for determining whether the striking surface 20a is pressed or for calculating the depression amount (depression value) of the striking surface 20a is constant, it is difficult to correctly perform the determination of pressing or the calculation of the depression value.

[0155] However, in the present embodiment, basically, according to the update time of every 1 second set in the reference value update timer T1, the reference value of the pressure-sensitive sensor 24 is updated based on the output value of the pressure-sensitive sensor 24. Thereby, the determination of pressing or the calculation of the depression value can be correctly performed. As a result, the sensitivity of pressing the striking surface 20a can be improved.

[0156] The 1-second update time set in the reference value update timer T1 is 0.1 times the stabilization time of about 10 seconds of the electronic percussion instrument 1 in the present embodiment. Furthermore, as described above, the stabilization time is the time from when the pressing state of the striking surface 20a is instantaneously released until the output value of the pressure-sensitive sensor 24 becomes the lowest (until it does not change), and from the release of the pressing until the output value of the pressure-sensitive sensor 24 stabilizes. The output value of the pressure-sensitive sensor 24 is likely to change significantly immediately after the striking of the striking surface 20a or after the release of the pressing, and the longer the stabilization time, the longer the period during which such significant changes occur. Therefore, by setting the update time to 0.1 times or more of the stabilization time, it is difficult to obtain the output value of the pressure-sensitive sensor 24 that changes significantly immediately after the striking of the striking surface 20a or after the release of the pressing, and thus the reference value can be appropriately set. As a result, the sensitivity of pressing the striking surface 20a can be further improved.

[0157] In addition, it is preferably that the update time is set to 0.5 times or less of the stabilization time, and more preferably that the update time is set to 0.3 times or less of the stabilization time. The shorter the update time, the earlier the reference value can approach the stable value of the pressure-sensitive sensor 24, and thus the sensitivity of pressing the striking surface 20a can be improved.

[0158] The reference value is calculated by averaging the average output value of the pressure-sensitive sensor 24 stored in the reference value calculation ring buffer 43d at a specified timing of regular processing. That is, the reference value is calculated by averaging the average output value of the pressure-sensitive sensor 24 obtained during a specified sampling time. Thus, even if the output value of the pressure-sensitive sensor 24 temporarily fluctuates greatly due to the vibration of the hitting surface 20a after hitting or the release of pressing on the hitting surface 20a or various noises, the reference value can be calculated by averaging the said output value, and the reference value can be set appropriately.

[0159] In the reference value calculation ring buffer (storage component) 43d, the average output value of the pressure-sensitive sensor 24 is stored (saved) for each update time. Thus, when the update time arrives, a new average output value of the pressure-sensitive sensor 24 is stored, and the reference value can be calculated by averaging the newly stored average output value and the average output value of the pressure-sensitive sensor 24 stored in the past. Therefore, it is not necessary to continuously store the average output value of the pressure-sensitive sensor 24 during the sampling time, and thus the storage capacity of the average output value of the pressure-sensitive sensor 24 can be reduced.

[0160] Eight average output values of the pressure-sensitive sensor 24 are stored in the reference value calculation ring buffer 43d, and a new average output value is stored in the reference value calculation ring buffer 43d at an update time of every 1 second. Therefore, the basic sampling time becomes 8 seconds. The sampling time of 8 seconds is 0.8 times the stabilization time of 10 seconds.

[0161] If the sampling time is 0.8 times or more the stabilization time from the state where the hitting surface 20a swings the most to stabilization, the sampling time can be obtained sufficiently long relative to the stabilization time. Thus, even if the hitting surface 20a temporarily vibrates greatly during the sampling time, the output value of the pressure-sensitive sensor 24 when the said vibration has sufficiently decayed can be obtained. Therefore, the reference value can be set more appropriately.

[0162] In addition, it is preferable to set the sampling time to 2 times or less the stabilization time, and more preferably to set the sampling time to 1.5 times or less the stabilization time. The shorter the sampling time, the more difficult it is to use the stable value of the pressure-sensitive sensor 24 before hitting, and the easier it is to use the stable value of the pressure-sensitive sensor 24 after hitting. Therefore, the reference value can be set more appropriately.

[0163] The electronic percussion instrument 1 prohibits the update of the reference value from the time when the hitting surface 20a is hit until 10 seconds of stabilization time has elapsed. As a result, the reference value can be updated without using the average output value of the pressure-sensitive sensor 24 that is likely to change due to the hitting surface 20a that vibrates greatly after hitting, and thus the reference value can be set appropriately.

[0164] The prohibition of updating the reference value from when the striking surface 20a is struck is executed by temporarily setting the update time of the reference value update timer T1, which represents the time until the next update of the reference value, to 10 seconds after the strike. Thereby, the process for prohibiting the update of the reference value can be simplified.

[0165] In addition, it is also possible to prohibit the update of the reference value from when the striking surface 20a is struck until after a stabilization time has elapsed. Preferably, the update of the reference value is prohibited until 2 times or less of the stabilization time has elapsed, and more preferably until 1.3 times or less of the stabilization time has elapsed. By shortening the time for prohibiting the update of the reference value, when the striking surface 20a is continuously struck, the time period during which the update of the reference value cannot be performed can be shortened, and thus the reference value can be appropriately set.

[0166] The electronic percussion instrument 1 prohibits the update of the reference value during the period when the striking surface 20a is pressed and until 1 second has elapsed since the pressing of the striking surface 20a is released. Thereby, as described above, an appropriate depression value can be obtained, and the reference value can be appropriately set. The prohibition of the update of the reference value is executed by setting the update time of the reference value update timer T1, which represents the time until the next update of the reference value, to 1 second each time in the periodic process during the period when the striking surface 20a is pressed. Thereby, the process for prohibiting the update of the reference value can be simplified.

[0167] Furthermore, during the period when the striking surface 20a is pressed or during the striking process, 0.1 milliseconds is not subtracted from the reference value update timer T1 each time in the periodic process, thereby prohibiting the update of the reference value during the period when the striking surface 20a is pressed or after the strike. As a result, the process for prohibiting the update of the reference value can be further simplified.

[0168] In addition, it is also possible to prohibit the update of the reference value after the pressing of the striking surface 20a is released until 0.1 times (1 second in this embodiment) or more of the stabilization time has elapsed. Since the vibration of the striking surface 20a after the pressing is released is smaller than the vibration when the striking surface 20a is struck and is likely to decay earlier, if the time for prohibiting the update of the reference value after the pressing of the striking surface 20a is released is 0.1 times or more of the stabilization time, the reference value can be appropriately set.

[0169] Furthermore, the time for prohibiting the update of the reference value after the pressing of the striking surface 20a is released is preferably 0.5 times or less of the stabilization time, and more preferably 0.3 times or less of the stabilization time. By shortening the time for prohibiting the update of the reference value, the responsiveness of updating the reference value after the pressing of the striking surface 20a is released can be improved.

[0170] The electronic percussion instrument 1 calculates the striking position on the striking surface 20a based on the output value of the pressure-sensitive sensor 24, the output value of the head vibration sensor 28, and the output value of the rim vibration sensor 32. Since the pressure-sensitive sensor 24 detects the pressing on the central portion of the striking surface 20a, the output value of the pressure-sensitive sensor 24 is more likely to increase as the striking position gets closer to the central portion. The head vibration sensor 28 detects the vibration of the peripheral portion rather than the central portion of the striking surface 20a, so it is easy to make the output value of the pressure-sensitive sensor 24 corresponding to the striking position different from the output value of the head vibration sensor 28. Furthermore, when viewed from above, the head vibration sensor 28 overlaps with the rim vibration sensor 32, so it is easy to make the ratio of their output values close to a certain value at each striking position. By using these output values, the electronic percussion instrument 1 can improve the detection accuracy of the striking position even if the striking position expands or becomes multiple. In particular, the electronic percussion instrument 1 can simulate the playing methods of conga drums or bongo drums that are easy to have an expanded or multiple striking position when striking the striking surface 20a by hand.

[0171] Furthermore, the electronic percussion instrument 1 calculates the edge degree E of the striking position based on the peak ratio characteristic quantity X1 which is the ratio of the peak Pzhm of the head vibration sensor 28 to the peak Pzrm of the rim vibration sensor 32, the piezoresistive peak characteristic quantity X2 which is the peak of the displacement amount of the pressure-sensitive sensor 24 relative to the reference value, and the pitch characteristic quantity X3 which is the pitch of the initial half-wave of the head vibration sensor 28. As described above, the respective characteristic quantities X1, X2, and X3 are likely to change according to the striking position. By calculating the edge degree E by using the respective characteristic quantities X1, X2, and X3, the detection accuracy of the striking position can be improved.

[0172] In particular, when calculating the edge degree E, the weighting coefficients W1, W2, W3, and b which are calculated for each product design of the electronic percussion instrument 1 and determined based on the shape etc. of the electronic percussion instrument 1 are used. Specifically, the edge degree E is calculated based on the imaginary edge degree A obtained by adding the products of the weighting coefficients W1, W2, W3 which respectively represent the importance of the respective characteristic quantities X1, X2, X3 and the corresponding respective characteristic quantities X1, X2, X3, and then adding the weighting coefficient b as a constant term. Thereby, the detection accuracy of the striking position can be further improved for each product design of the electronic percussion instrument 1, that is, for each shape of the electronic percussion instrument 1. Furthermore, since the weighting coefficients W1, W2, W3, and b are calculated for the electronic percussion instrument 1 in the actual striking design stage, the detection accuracy of the striking position can be further improved even if the striking position expands or becomes multiple.

[0173] The marginal degree E calculated by substituting the imaginary marginal degree A into the standard S-shaped function takes a value of 0 or more and 1 or less. Therefore, when the marginal degree E is a value between 0 and 1, it is easy to set the volume ratio of the musical sound signal when outputting a musical sound signal obtained by mixing the musical sound signal when the central part of the hitting surface 20a is hit and the musical sound signal when the peripheral part is hit according to the ratio between the values.

[0174] Next, refer to Figure 9 (a) of Figure 9 and Figure 11 (b) to

[0175] First, refer to Figure 9 (a) of Figure 9 to describe the overall structure of the MIDI controller 80. Figure 9 (a) is a plan view of the MIDI controller 80 in the second embodiment. Figure 9 (b) is Figure 9 a cross-sectional view of the MIDI controller 80 taken along the line IXb-IXb of Figure 9 (a). Furthermore, for easy understanding, the left side, right side, lower side, and upper side of the paper surface of Figure 9 (a) are respectively set as the left side, right side, front side (performer side), and back side of the MIDI controller 80, and the upper side and lower side of the paper surface of

[0176] As shown in Figure 9 (a), the MIDI controller 80 is a device that uses a pressure-sensitive sensor (strike detection component) 24 to detect a strike (press) on the hitting surface 83 and outputs an instruction based on the strike to the outside. The MIDI controller 80 includes: a rectangular parallelepiped-shaped housing 81, a plurality of operation members 82 provided on the left and right sides of the housing 81, 16 hitting surfaces 83 provided on the housing 81, 16 elastic bodies 84 formed on the upper surface and having the hitting surfaces 83, and a pressure-sensitive sensor 24 that detects a strike on the hitting surface 83. Furthermore, in Figure 9 (a), the area where the plurality of operation members 82 are provided is surrounded by a two-dot chain line, and the illustration of each operation member 82 is omitted. The 16 hitting surfaces 83 and elastic bodies 84 are arranged in 4 rows × 4 columns. Furthermore, in Figure 9 (a), only one hitting surface 83 and elastic body 84 in the lower left are labeled.

[0177] As shown Figure 9 In (b) of FIG., on the upper surface of the housing 81, an opening hole 81a is formed at a position corresponding to the striking surface 83. Inside the housing 81, a control device 90 for outputting a striking indication is built in. On the upper surface of the control device 90, a pressure-sensitive sensor 24 is provided so as to be located more inward than the inner periphery of the opening hole 81a.

[0178] The elastic body 84 is a rubber member that covers the upper part of the pressure-sensitive sensor 24. The elastic body 84 protrudes upward from the opening hole 81a, and the striking surface 83 is formed by the upper surface of the elastic body 84 that protrudes upward. A rubber film 85 that abuts against the inner side of the housing 81 at the edge of the opening hole 81a extends from the side surface of the elastic body 84. By the rubber film 85 abutting against the inner side of the housing 81, the upward displacement of the elastic body 84 is restricted.

[0179] In the state where the upward displacement is restricted, the elastic body 84 is pressed against the pressure-sensitive sensor 24. In Figure 9 In (b) of FIG., the elastic body 84 in the state where no load is applied is shown by a two-dot chain line. When the striking surface 83 is struck, the pressure-sensitive sensor 24 is pressed via the elastic body 84, and the pressure-sensitive sensor 24 detects the strike. The lower surface of the elastic body 84 that abuts against the pressure-sensitive sensor 24 is formed in a shape that tapers downward toward the front end so that the more strongly it is pressed against the pressure-sensitive sensor 24, the more the contact area between the pressure-sensitive sensor 24 and the elastic body 84 increases. Thus, the output value of the pressure-sensitive sensor 24 can be easily changed according to the intensity of the strike on the striking surface 83.

[0180] Furthermore, since the elastic body 84 is compressed between the striking surface 83 and the pressure-sensitive sensor 24, there is no clearance between the striking surface 83 and the pressure-sensitive sensor 24. Thus, even if the striking surface 83 is not strongly pressed, the output value of the pressure-sensitive sensor 24 can be changed. Thereby, the sensitivity of the pressure-sensitive sensor 24 with respect to the strike (press) on the striking surface 83 can be improved.

[0181] In the MIDI controller 80, from the state where the striking surface 83 is strongly pressed and the pressure is instantly released until the output value of the pressure-sensitive sensor 24 becomes the lowest (until it does not change), the stabilization time from when the pressure is released until the output value of the pressure-sensitive sensor 24 stabilizes is about 1 second. In the MIDI controller 80, the part that vibrates after the pressure is released is the rubber elastic body 84 that is less likely to vibrate compared to the head 20 of the first embodiment. Therefore, the stabilization time of the MIDI controller 80 is shorter than the stabilization time of the electronic percussion instrument 1 of the first embodiment.

[0182] Next, with reference to Figure 10 the electrical structure of the MIDI controller 80 will be described. Figure 10is a block diagram showing the electrical structure of the MIDI controller 80. The control device 90 of the MIDI controller 80 includes a CPU 91, a ROM 92, and a RAM 93, which are respectively connected via a bus 94. In addition, 16 pressure sensors 24, operation members 82, and an output unit 95, which are respectively provided on each of the 16 striking surfaces 83, are connected to the bus 94. A personal computer (PC) 96 is connected to the output unit 95, and a speaker 97 is connected to the PC 96.

[0183] When the striking surface 83 is struck, the MIDI controller 80 outputs a strike instruction corresponding to the detection result (output value) of the pressure sensor 24 based on the strike from the CPU 41 to the PC 96 via the output unit 95. In the PC 96, a music piece is produced based on the strike instruction from the output unit 95, or a timbre or various effects are added to the strike instruction. Thereafter, the music sound based on the music sound signal output from the PC 96 is emitted from the speaker 97.

[0184] The CPU 91 is an arithmetic device that controls each unit connected via the bus 94. The ROM 92 is a non-rewritable memory. A control program 92a is stored in the ROM 92. When the control program 92a is executed by the CPU 91, initialization processing is immediately executed after the power of the MIDI controller 80 is turned on, and then periodic processing is executed. The initialization processing is the same as the Figure 6 initialization processing in (a) of the first embodiment.

[0185] The RAM 93 is a memory that can rewrite and store various working data or flags, etc. when the CPU 91 executes programs such as the control program 92a. A pressure sensor value circular buffer 43c, a reference value calculation circular buffer 43d, an average value memory 43e, a reference value memory 43f, a strike processing flag 43g, a previous average value memory 93a, and a strike level memory 93b are respectively provided in the RAM 93.

[0186] The previous average value memory 93a is a memory that stores the value of the average value memory 43e at this time before the value of the average value memory 43e is updated. The value of the previous average value memory 93a is immediately initialized to "0" when the power of the MIDI controller 80 is turned on and after the initialization processing is executed. In Figure 11 the periodic processing, before the value of the average value memory 43e is updated, the current value of the average value memory 43e is saved in the previous average value memory 93a ( Figure 11 , S72).

[0187] The strike level memory 93b is a memory that stores the strike level, which represents the peak value of the displacement amount of the pressure-sensitive sensor 24 relative to the reference value as the intensity of the strike. The value of the strike level memory 93b is immediately initialized to "0" when the power of the MIDI controller 80 is turned on and after the initialization process is executed. In Figure 11 the periodic process, after the striking surface 83 is struck and 2 milliseconds have elapsed, the peak value of the displacement amount of the pressure-sensitive sensor 24 relative to the reference value within the 2 milliseconds is stored in the strike level memory 93b as the strike level ( Figure 11 , S88).

[0188] Next, a description will be given of the periodic process executed by the CPU 91 of the MIDI controller 80 with reference to Figure 11 . In the periodic process, the acquisition of the output value of the pressure-sensitive sensor 24, the update of the reference value, or the calculation of the strike level at the time point when the periodic process is executed is performed. The periodic process is repeatedly executed every 0.1 millisecond through an interrupt process at intervals of 0.1 millisecond.

[0189] Figure 11 is a flowchart of the periodic process. In the periodic process, first, the sensor value (output value) of the pressure-sensitive sensor 24 is acquired and added to the pressure-sensitive sensor value ring buffer 43c (S70). Since the periodic process is executed every 0.1 millisecond, the value of the pressure-sensitive sensor value ring buffer 43c is updated every 0.1 millisecond.

[0190] After the process of S70, it is confirmed whether eight or more valid values are stored in the pressure-sensitive sensor value ring buffer 43c (S71). Furthermore, a valid value is a value from 0 to 1024 that the pressure-sensitive sensor 24 can acquire. When eight or more valid values are not stored in the pressure-sensitive sensor value ring buffer 43c (S71: No), the periodic process ends and waits until eight or more valid values are stored in the pressure-sensitive sensor value ring buffer 43c, that is, until 0.8 milliseconds or more have elapsed since the initialization process.

[0191] When eight or more valid values are stored in the pressure-sensitive sensor value ring buffer 43c (S71: Yes), the value of the average value memory 43e is saved in the previous average value memory 93a (S72). Subsequently, referring to the values in the pressure-sensitive sensor value ring buffer 43c, the values of the pressure-sensitive sensor 24 for 0.8 milliseconds are averaged by tracing back from the current periodic process, and the average output value of the pressure-sensitive sensor 24 is calculated and stored in the average value memory 43e (S73). Thereby, the output value (average output value) of the pressure-sensitive sensor 24 from which electrical noise has been removed is obtained.

[0192] After the processing of S73, it is confirmed whether the value of the reference value memory 43f is a valid value (S74). A valid value is a value from 0 to 1024 that the pressure-sensitive sensor 24 can acquire. In the initialization process, an invalid value is stored in the reference value memory 43f. Therefore, in the first processing of S74 after the initialization process, the value of the reference value memory 43f is not a valid value (S74: No). In this case, the value of the average value memory 43e is filled into the reference value calculation circular buffer 43d (S75). Thereafter, the value of the average value memory 43e is stored in the reference value memory 43f in such a way that the reference value obtained by averaging the values in the reference value calculation circular buffer 43d is stored in the reference value memory 43f (S76). Subsequently, 0.1 seconds is set in the reference value update timer T1 indicating the time until the value of the reference value memory 43f is updated next (S77).

[0193] In the processing of S74, when the value of the reference value memory 43f is a valid value (S74: Yes), 0.1 milliseconds is subtracted from the reference value update timer T1 (S78). After the processing of S78, it is confirmed whether the strike processing flag 43g indicating the start of the processing based on the strike on the striking surface 83 is off (S79).

[0194] When the strike processing flag 43g is off (S79: Yes), the processing based on the strike (press) has not started. Therefore, it is confirmed whether the difference obtained by subtracting the output value of the current pressure-sensitive sensor 24 (the latest value of the pressure-sensitive sensor value circular buffer 43c) from the value of the last average value memory 93a is greater than the strike threshold N4 (S80). In the processing of S80, when the output value of the pressure-sensitive sensor 24 in this regular processing is significantly lower than the strike threshold N4 compared to the value of the average value memory 43e (the value of the last average value memory 93a) in the previous regular processing until the last non-struck time, it is determined that the striking surface 83 has been struck.

[0195] In the processing of S80, when the difference obtained by subtracting the latest value of the pressure-sensitive sensor value circular buffer 43c from the value of the last average value memory 93a is greater than the strike threshold N4 (S80: Yes), the striking surface 83 has been struck. Therefore, the strike processing flag 43g is set to on (S81), and 1 second is set in the reference value update timer T1 (S82).

[0196] After the process of S82, 0.1 milliseconds are added to the strike timer T4 that has been initialized to 0 seconds through initialization processing or the like (S83). The strike timer T4 represents the elapsed time since it was determined that the striking surface 83 has been struck. After the process of S83, it is confirmed whether the strike timer T4 is 2 milliseconds (S84). When the strike timer T4 is less than 2 milliseconds (S84: No), the time required to obtain the peak Pm of the pressure-sensitive sensor 24 has not elapsed, so the periodic process ends. In the next periodic process, the strike processing flag 43g becomes ON (S79: Yes), so in the process of S83, 0.1 milliseconds are added to the strike timer T4, and waiting is performed until the strike timer T4 becomes 2 milliseconds.

[0197] In the process of S84, when the strike timer T4 is 2 milliseconds (S84: Yes), the time required to obtain the peak Pm of the pressure-sensitive sensor 24 has elapsed. Therefore, first, for preparation when the striking surface 83 is struck next time, the strike timer T4 is initialized to 0 seconds (S85), and the strike processing flag 43g is set to OFF (S86).

[0198] After the process of S86, the peak Pm of the pressure-sensitive sensor 24 within 2 milliseconds is calculated based on the value of the pressure-sensitive sensor value ring buffer 43c (S87). Subsequently, the strike level is calculated by subtracting the peak Pm from the reference value of the reference value memory 43f ( Figure 5 the peak feature quantity X2 in (a)), and the strike level is stored in the strike level memory 93b (S88). Thus, in the process of S88 (the pressing detection component, the pressing detection step), the pressing on the striking surface 83 is detected as the strike level based on the difference between the output value (peak Pm) of the pressure-sensitive sensor 24 and the reference value. After the process of S88, the strike information (strike indication) corresponding to the strike level in the strike level memory 93b is sent to the PC 96 via the output unit 95 (S89), and the periodic process ends.

[0199] In the process of S80, when the difference obtained by subtracting the latest value of the pressure-sensitive sensor value ring buffer 43c from the value of the previous average value memory 93a is less than or equal to the strike threshold N4 (S80: No), the striking surface 83 has not been struck, so the process proceeds to the process for updating the reference value. In the process for updating the reference value, first, it is confirmed whether the reference value update timer T1 has become 0 seconds or less (S90). When the reference value update timer T1 is greater than 0 seconds (S90: No), after updating the value of the reference value memory 43f, the timing for updating the value next time has not arrived, so the periodic process ends.

[0200] When the reference value update timer T1 becomes 0 seconds or less (S90: Yes), it is time to update the reference value. Therefore, 0.1 seconds is set in the reference value update timer T1 (S91), and the average output value of the pressure-sensitive sensor 24 stored in the average value memory 43e is added to the reference value calculation circular buffer 43d (S92). Subsequently, the reference value is calculated by averaging the average output values of the total eight pressure-sensitive sensors 24 stored in the reference value calculation circular buffer 43d, and the reference value is saved in the reference value memory 43f (S93), and the periodic process ends.

[0201] Similar to the first embodiment, in the MIDI controller (tone generation device) 80 as described above, the elastomer 84 is compressed between the striking surface 83 and the pressure-sensitive sensor 24. Therefore, there is no clearance between the striking surface 83 and the pressure-sensitive sensor 24, so that even if the striking surface 83 is not strongly struck (pressed), the output value of the pressure-sensitive sensor 24 can be changed. Furthermore, basically according to the update time of every 0.1 second set in the reference value update timer T1, the reference value of the pressure-sensitive sensor 24 is updated according to the output value of the pressure-sensitive sensor 24. Therefore, the judgment of pressing or the calculation of the pressing value can be correctly performed. As a result, the sensitivity of pressing the striking surface 83 can be improved.

[0202] When the striking surface 83 is not struck, the update time of 0.1 second basically set in the reference value update timer T1 is 0.1 times the stable time of 1 second of the MIDI controller 80. Thus, the reference value can be appropriately set in the same manner as in the first embodiment.

[0203] In addition, the average output values of the eight pressure-sensitive sensors 24 are stored in the reference value calculation circular buffer 43d, and the new average output value is basically stored in the reference value calculation circular buffer 43d according to the update time of every 0.1 second. Therefore, the basic sampling time becomes 0.8 seconds. The reference value is calculated by averaging the average output values of the pressure-sensitive sensor 24 obtained during the sampling time that is 0.8 times the stable time of the MIDI controller 80. As a result, the reference value can be appropriately set in the same manner as in the first embodiment.

[0204] As described above, the present invention has been described based on the embodiments. However, the present invention is not limited by any of the above-described embodiments, and it can be easily inferred that various modifications and variations can be made without departing from the gist of the present invention. For example, the shapes, sizes, and raw materials of the respective parts of the housing 10 or the heads 20 and 21 can be appropriately changed. The speaker 17 can also be omitted from the electronic percussion instrument 1, and the electronic percussion instrument 1 can be connected to an external speaker. The update time of the reference value or the sampling time for obtaining the output value of the pressure-sensitive sensor for updating the reference value can also be appropriately changed.

[0205] In the first embodiment, the electronic percussion instrument 1 that simulates a bongo drum has been described, but it is not necessarily limited thereto. The present invention can also be applied to electronic percussion instruments that simulate other percussion instruments such as a snare drum, a bass drum, cymbals, and a conga drum. In addition, the present invention can also be applied to input devices other than the MIDI controller 80 or tone generation devices such as electronic keyboard instruments that perform percussion or pressing (pushing in) operations.

[0206] In the first embodiment, the case where the elastic body 26 is an elastic material made of sponge has been described, but it is not necessarily limited thereto. The elastic body 26 can also be formed of an elastic material made of rubber or thermoplastic elastomer. In addition, the elastic body 84 in the second embodiment can also be made of sponge or thermoplastic elastomer. In addition, the cushion 30 can also be made of rubber or thermoplastic elastomer.

[0207] In the first embodiment, the case where the striking position of the striking surface 20a is calculated based on the output value of the pressure-sensitive sensor 24, the output value of the head vibration sensor 28, and the output value of the rim vibration sensor 32 has been described, but it is not necessarily limited thereto. The presence or absence of pressing on the striking surface 20a using a drumstick or the like or the amount of pushing in can be detected by the pressure-sensitive sensor 24, and the vibration of the striking surface 20a can be detected by the head vibration sensor 28 at the same time. Thereby, it is possible to simulate a drumstick strike in which a drumstick attached to the striking surface 20a is struck with another drumstick, and a performance method in which the striking surface 20a is struck with another drumstick or hand while a drumstick or hand is attached to the striking surface 20a. In the drumstick strike where the pressed place is the same as the striking position and the performance method where the pressed place is different from the striking position, the ratio of the output value of the rim vibration sensor 32 to the output value of the pressure-sensitive sensor 24 or the head vibration sensor 28 is different, so the differences between these performance methods can be distinguished.

[0208] In the first embodiment, the case where the striking position (edge degree E) is calculated based on each feature quantity X1, feature quantity X2, and feature quantity X3 has been described, but it is not necessarily limited thereto. For example, the striking position can also be calculated based on the time differences of the peaks of the pressure-sensitive sensor 24, the head vibration sensor 28, and the rim vibration sensor 32, respectively. In addition, the striking position can also be calculated using the ratio of the peak of the pressure-sensitive sensor 24 to the peak of the head vibration sensor 28, or the ratio of the peak of the pressure-sensitive sensor 24 to the peak of the rim vibration sensor 32.

[0209] In the first embodiment, the case where the head vibration sensor 28 and the rim vibration sensor 32 are formed of piezoelectric elements has been described, but it is not necessarily limited thereto. The head vibration sensor 28 and the rim vibration sensor 32 may be formed of contact-type detection elements such as electric type or electrostatic capacitance type, or non-contact detection elements. In addition, the contact-type head vibration sensor 28 may be directly mounted on the heads 20 and 21. The pressure-sensitive sensor 24 is not limited to the case of piezoresistive elements such as piezoresistors, and the pressure-sensitive sensor 24 may be an electrostatic capacitance type.

[0210] In the above-described manner, the case where the greater the pressure applied to the pressure-sensitive sensor 24, that is, the more strongly the striking surface 20a is pressed or struck, the smaller the output value of the pressure-sensitive sensor 24 has been described, but it is not necessarily limited thereto. It may also be configured such that the greater the pressure applied to the pressure-sensitive sensor 24, the greater the output value of the pressure-sensitive sensor 24. In any case, in the first embodiment, if the absolute value of the difference between the reference value and the output value (average output value) of the pressure-sensitive sensor 24 is greater than the pressing threshold N2, it is determined that the striking surface 20a is pressed. Further, in any case, in each embodiment, the absolute value of the difference between the peak value Pm of the pressure-sensitive sensor 24 and the reference value is set as the feature quantity X2 or the striking level.

[0211] In addition, in any case, in the second embodiment, if the absolute value of the difference between the output value of the pressure-sensitive sensor 24 (the latest value of the pressure-sensitive sensor value ring buffer 43c) and the output value of the pressure-sensitive sensor 24 (average output value) up to the previous periodic process is greater than the striking threshold N4, it is determined that the striking surface 83 is struck. In the case where the greater the pressure applied to the pressure-sensitive sensor 24, the greater the output value of the pressure-sensitive sensor 24, in the first embodiment, the pressing value is calculated based on the value obtained by subtracting the value obtained by adding the reference value and the pressing threshold N2 from the output value (average output value) of the pressure-sensitive sensor 24. Furthermore, in the calculation of the pressing value, the pressing threshold N2 may not be used, and the pressing value may be calculated based on the absolute value of the difference between the reference value and the output value (average output value) of the pressure-sensitive sensor 24.

[0212] In the first embodiment, the case where the output values of the current respective sensors 24, 28, and 32 are obtained based on the latest values of the corresponding respective ring buffers 43a, 43b, and 43c has been described, but it is not necessarily limited thereto. A memory that stores the output values of the current respective sensors 24, 28, and 32 may be separately provided from the respective ring buffers 43a, 43b, and 43c.

[0213] In addition, the case where the peak values of the respective sensors 24, 28, and 32 are calculated based on the values of the corresponding ring buffers 43a, 43b, and 43c has been described, but it is not necessarily limited thereto. It may also be configured such that, during each periodic process within a specified time (e.g., 5 milliseconds) after the striking surface 20a has been struck, if the current output values of the respective sensors 24, 28, and 32 are greater than the peak values of the respective sensors 24, 28, and 32 saved up to the previous time, the peak values of the respective sensors 24, 28, and 32 are updated.

[0214] In the first embodiment, the case where, when the difference obtained by subtracting the average output value of the pressure-sensitive sensor 24 from the reference value is greater than the pressing threshold N2, it is determined that there is a possibility that the striking surface 20a has been pressed has been described, but it is not necessarily limited thereto. When the average output value of the pressure-sensitive sensor 24 is smaller than the reference value, it may also be determined that there is a possibility that the striking surface 20a has been pressed. However, in this case, it is preferable to set as the reference value a value slightly higher than the value obtained by averaging the average output values of the eight pressure-sensitive sensors 24 stored in the pressure-sensitive sensor value ring buffer 43c.

[0215] In the second embodiment, the case where, when the difference obtained by subtracting the latest value of the pressure-sensitive sensor value ring buffer 43c from the value of the previous average value memory 93a is greater than the striking threshold N4, it is determined that the striking surface 83 has been struck (pressed) has been described, but it is not necessarily limited thereto. It may also be determined that the striking surface 83 has been struck (pressed) based on the difference between the reference value and the latest value of the pressure-sensitive sensor value ring buffer 43c.

[0216] In the above-described manner, the case where the weighting coefficients W1, W2, W3, and the bias b are calculated by supervised learning of machine learning according to the design of each product of the electronic percussion instrument 1 and stored as fixed values in the weighting coefficient data 42b at the time of product shipment has been described, but it is not necessarily limited thereto. The weighting coefficients W1, W2, W3, and the bias b may also be calculated by machine learning using the data when the user strikes the striking surface 20a. In this case, since the region of the central portion of the striking surface 20a where the marginality E should be 0 and the region of the peripheral portion of the striking surface 20a where the marginality E should be 1 can be set for each user, it is possible to easily generate the desired musical sound.

[0217] In the above-described manner, a case has been described where a pressure-sensitive sensor 24 is disposed on the back surface 20b side of the central portion of the hitting surface 20a, a head vibration sensor 28 is disposed on the back surface 20b side of the peripheral portion of the hitting surface 20a, and a rim vibration sensor 32 is disposed at a position overlapping the head vibration sensor 28 when the hitting surface 20a is viewed from above, but it is not necessarily limited thereto. The positions of the respective sensors 24, sensor 28, and sensor 32 can also be appropriately changed. Based on the positions of the respective sensors 24, sensor 28, and sensor 32, and by machine learning, weighting coefficients W1, weighting coefficient W2, weighting coefficient W3, and weighting coefficient b corresponding to the output values of the respective sensors 24, sensor 28, and sensor 32 are calculated, whereby the calculation accuracy of the hitting position (edge degree E) can be improved.

[0218] In the above-described first embodiment, a case has been described where, during the period when the hitting surface 20a is pressed or during the hitting process, 0.1 milliseconds is not subtracted from the reference value update timer T1 in each periodic process, but it is not necessarily limited thereto. It is also possible to set 1 second or 10 seconds for the reference value update timer T1 during the pressing of the hitting surface 20a and after the hitting. Therefore, during the period when the hitting surface 20a is pressed or during the hitting process, 0.1 milliseconds can also be subtracted from the reference value update timer T1 in each periodic process.

Claims

1. A musical tone generating device, characterized in that, Comprising: A striking surface; A pressure-sensitive sensor configured on the back side of the striking surface to detect pressure changes; A strike detection component that detects a strike on the striking surface; An elastomer compressed between the striking surface and the pressure-sensitive sensor; And A control device that outputs an indication corresponding to the output value of the pressure-sensitive sensor, and The control device includes: A pressing detection component that detects a press on the striking surface based on the difference between the output value of the pressure-sensitive sensor and a reference value; An updating component that updates the reference value according to the output value of the pressure-sensitive sensor at each update time; and A post-strike update prohibition component that instantaneously releases the press from the state of pressing the striking surface until the output value of the pressure-sensitive sensor does not change, and sets the time from the release of the press until the output value of the pressure-sensitive sensor stabilizes as the stabilization time. The post-strike update prohibition component prohibits the updating component from updating the reference value from when the strike on the striking surface is detected by the strike detection component until after the stabilization time has elapsed.

2. The musical tone generating device according to claim 1, wherein, The updating component averages the output values of the pressure-sensitive sensor obtained during the sampling time to calculate the reference value.

3. The musical tone generating device according to claim 2, characterized in that, Instantaneously release the press from the state of pressing the striking surface until the output value of the pressure-sensitive sensor does not change, and set the time from the release of the press until the output value of the pressure-sensitive sensor stabilizes as the stabilization time, The sampling time is 0.8 times or more of the stabilization time.

4. The musical tone generating device according to claim 2 or 3, characterized in that, The control device includes a storage component that stores the output values of the pressure-sensitive sensor at each update time, The updating component averages the output values of the pressure-sensitive sensor stored in the storage component during the sampling time to calculate the reference value.

5. The musical tone generating device according to any one of claims 1 to 3, characterized in that, Instantaneously release the press from the state of pressing the striking surface until the output value of the pressure-sensitive sensor does not change, and set the time from the release of the press until the output value of the pressure-sensitive sensor stabilizes as the stabilization time, The update time is 0.1 times or more of the stabilization time.

6. The musical tone generating device according to any one of claims 1 to 3, characterized in that The pressing detection component includes a pressing determination component that determines whether the striking surface is pressed based on the difference between the output value of the pressure-sensitive sensor and the reference value, The control device includes a pressing-time update prohibition component that prohibits the updating component from updating the reference value during the period when the pressing determination component determines that the striking surface is pressed.

7. The musical tone generating device according to any one of claims 1 to 3, characterized in that Comprising: A position calculation component that calculates the strike position on the striking surface based on the output value of the pressure-sensitive sensor.

8. The musical tone generating device according to claim 7, characterized in that, The pressure-sensitive sensor detects the press on the striking surface, and the sound generation device includes: A head vibration sensor that detects the vibration of the striking surface; and A rim vibration sensor that detects the vibration of the frame for mounting the striking surface, and The position calculation component calculates the strike position on the striking surface based on the output value of the pressure-sensitive sensor, the output value of the head vibration sensor, and the output value of the rim vibration sensor.

9. A musical tone generating method that outputs an indication corresponding to an output value of a pressure-sensitive sensor in a musical tone generating device including a striking surface, a pressure-sensitive sensor, a striking detection component, and an elastic body. The pressure-sensitive sensor is disposed on the back side of the striking surface to detect a pressure change. The striking detection component detects a strike on the striking surface. The elastic body is compressed between the striking surface and the pressure-sensitive sensor. The musical tone generating method is characterized by including: a pressing detection step of detecting a press on the striking surface based on a difference between the output value of the pressure-sensitive sensor and a reference value; an updating step of updating the reference value at each update time according to the output value of the pressure-sensitive sensor; and a post-strike update prohibition step of instantaneously releasing the press from the state of pressing the striking surface until the output value of the pressure-sensitive sensor does not change, and setting the time from the release of the press until the output value of the pressure-sensitive sensor stabilizes as a stabilization time. The post-strike update prohibition step prohibits the update of the reference value in the updating step from when the strike on the striking surface is detected by the striking detection component until after the stabilization time has elapsed.

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