Electronic percussion instrument, control device, force calculation method, and storage medium

Abstract

The invention provides an electronic percussion instrument, a control device, a force calculation method, and a computer readable storage medium, which can improve the precision of force for striking the peripheral part of a drumhead. An electronic drum is provided with: a head sensor for detecting striking on a head; and a rim sensor for detecting vibrations of the rim and the main body. The force is calculated on the basis of the peak value of the drumhead sensor detected during the scanning time from the detection of the start of striking the drumhead, and the energy value of the rim sensor. The rim sensor detects vibration of the rim provided with the head or the main body portion, and thus sensitivity to the peripheral portion of the head is higher than that of the head sensor. When the energy value of the drum edge sensor is used for calculating the force, the precision of the force for striking the peripheral part of the drum surface can be improved.

Description

Technical Field

[0001] The invention relates to an electronic percussion instrument, a control device, a force calculation method and a computer-readable storage medium. Background Art

[0002] Patent document 1 discloses an electronic percussion instrument having a drumhead 5 configured as a striking surface to be struck by a drumstick or the like, and a drumhead sensor 21 disposed below the center of the drumhead 5. A buffer member 24 is disposed between the drumhead 5 and the drumhead sensor 21, and vibration when the drumhead 5 is struck by a drumstick or the like is transmitted to the drumhead sensor 21 via the buffer member 24. Then, a force is calculated based on an output value based on the vibration from the drumhead 5 detected by the drumhead sensor 21, and a musical sound is output based on the calculated force.

[0003] [Prior art literature]

[0004] [Patent Document]

[0005] [Patent Document 1] Japanese Patent Publication No. 2004-198657 Summary of the invention

[0006] [Problems to be solved by the invention]

[0007] In addition, the drumhead sensor 21 is provided at the lower part of the center of the drumhead 5. Therefore, even if the intensity of the hit is the same, the sensitivity of the drumhead sensor 21 to the peripheral part of the drumhead 5 is lower than the sensitivity to the central part of the drumhead 5. The intensity of the peripheral part of the drumhead 5 calculated based on the output value of the drumhead sensor 21 is smaller than the intensity of the hit of the same intensity that should be calculated to hit the central part of the drumhead 5. Therefore, there is a problem that the accuracy of the intensity of the hit on the peripheral part of the drumhead is reduced.

[0008] The present invention is made to solve the above-mentioned problem, and its purpose is to provide an electronic percussion instrument, a control device, a force calculation method and a computer-readable storage medium, which can improve the accuracy of the force for hitting the peripheral part of the drumhead.

[0009] [Technical means to solve the problem]

[0010] In order to achieve the above-mentioned purpose, the electronic percussion instrument of the present invention includes: a shell; a drumhead, which is arranged on the shell and constitutes a striking surface; a drumhead sensor, which detects a strike on the drumhead; a shell sensor, which detects vibration of the shell; a drumhead result acquisition unit, which acquires a detection result from the drumhead sensor; a shell result acquisition unit, which acquires a detection result from the shell sensor; and a force calculation unit, which calculates the force when the drumhead is struck based on the detection result acquired by the drumhead result acquisition unit and the detection result acquired by the shell result acquisition unit.

[0011] The control device of the present invention controls the sound source part based on the detection result of the drumhead sensor and the detection result from the shell sensor, the drumhead sensor detects the impact on the drumhead constituting the striking surface of the percussion instrument, and the shell sensor detects the vibration of the shell of the percussion instrument. The control device includes: a drumhead result acquisition unit, which acquires the detection result from the drumhead sensor; a shell result acquisition unit, which acquires the detection result from the shell sensor; and a force calculation unit, which calculates the force when the drumhead is hit based on the detection result acquired by the drumhead result acquisition unit and the detection result acquired by the shell result acquisition unit.

[0012] The computer-readable storage medium of the present invention stores a force calculation program. The force calculation program is a program that causes a computer to execute a force calculation process for calculating force, and the program causes the computer to execute the following steps: a drumhead result acquisition step, which acquires a detection result from a drumhead sensor, which detects a hit on a drumhead constituting a striking surface of an electronic percussion instrument; a shell result acquisition step, which acquires a detection result from a shell sensor, which detects vibration of a shell of the electronic percussion instrument; and a force calculation step, which calculates the force of the hit based on the detection result acquired by the drumhead result acquisition step and the detection result acquired by the shell result acquisition step.

[0013] In addition, the force calculation method of the present invention includes: a drumhead result acquisition step, acquiring a detection result from a drumhead sensor, wherein the drumhead sensor detects a strike on a drumhead constituting a striking surface of an electronic percussion instrument; a shell result acquisition step, acquiring a detection result from a shell sensor, wherein the shell sensor detects vibration of the shell of the electronic percussion instrument; and a force calculation step, calculating the force of the strike based on the detection result acquired by the drumhead result acquisition step and the detection result acquired by the shell result acquisition step. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a diagram for explaining the structure of an electronic drum.

[0015] Figure 2A1 is a diagram showing the output waveforms of the drum head sensor and the drum rim sensor when the striking position is the center of the drum head (diameter 12 inches). Figure 2B 1 is a diagram showing the output waveforms of the drum head sensor and the drum rim sensor when the distance between the striking position and the center of the drum head (diameter 12 inches) is 70 mm. Figure 2C The diagram shows output waveforms of the drum head sensor and the drum rim sensor when the distance between the striking position and the center of the drum head (diameter 12 inches) is 140 mm.

[0016] Figure 3 This is a functional block diagram of an electronic drum.

[0017] Figure 4A is a block diagram showing the electrical structure of an electronic drum. Figure 4B is a diagram schematically showing drum edge coefficient data. Figure 4C This is a diagram showing the relationship between the impact position and the weighting coefficient.

[0018] Figure 5 This is the main processing flow chart.

[0019] Figure 6 : is a block diagram showing the electrical configuration of a control device in a modified example.

[0020] [Explanation of Symbols]

[0021] 1: Electronic drums (electronic percussion instruments, percussion instruments)

[0022] 2: Main body (housing)

[0023] 5: Drum head

[0024] 6: Drum edge

[0025] 8: Drum head sensor

[0026] 9: Drum edge sensor (shell sensor)

[0027] 21a: Control program (force calculation program)

[0028] 25: Sound source (sound source department)

[0029] 50: Control device

[0030] 60: Drums (percussion instruments)

[0031] α: weighting coefficient

[0032] Vc: intensity

[0033] Er: Energy value

[0034] S1: drumhead result acquisition unit, shell result acquisition unit, drumhead result acquisition step, shell result acquisition step

[0035] S8: Hitting position detection unit

[0036] S9: Weighting coefficient acquisition unit

[0037] S10: force calculation unit, force calculation steps DETAILED DESCRIPTION

[0038] Hereinafter, preferred embodiments will be described with reference to the accompanying drawings. Figure 1 The structure of the electronic drum 1 according to the present embodiment will be described. Figure 1 1 is a diagram for explaining the structure of the electronic drum 1 . Figure 1 1 shows a cross section of the electronic drum 1, with a portion thereof omitted for illustration. Figure 1 The upper side is set as the upper side of the electronic drum 1, and the lower side is set as the lower side of the electronic drum 1.

[0039] like Figure 1 As shown, the electronic drum 1 is an electronic percussion instrument (percussion instrument) that simulates a drum played by a player using drumsticks, etc. The electronic drum 1 includes a main body 2, a sensor frame 4, a drum head 5, and a drum rim 6, and is configured to be assembled by sequentially stacking these components and fixing the drum rim 6 to the main body 2.

[0040] The main body 2 is a member that serves as the skeleton (shell) of the electronic drum 1, and is formed into a cylindrical shape by, for example, a wooden material or a resin material. A sensor frame 4, which will be described later, is accommodated in the inner periphery of the main body 2, and a drum head 5 and a drum rim 6, which will be described later, are provided on the upper end side of the main body 2. In addition, a plurality of engaging portions 3 are provided on the outer periphery of the main body 2.

[0041] The sensor frame 4 is a member for mounting the drumhead sensor 8 and the rim sensor 9 described later on the electronic drum 1, and for transmitting vibration generated by hitting the rim 6 to the rim sensor 9. The drumhead 5 is a portion of the striking surface that is struck by a drumstick or the like, and is formed by bonding a striking member 5a formed by weaving synthetic fibers into a mesh to a frame 5b.

[0042] The striking surface of the electronic drum 1 formed by the drumhead 5 is circular in a plan view, and its diameter is 12 inches (about 305 mm). In addition, the shape of the striking surface of the electronic drum 1 is not limited to a circle, and may be other shapes such as an ellipse or a rectangle. In addition, the diameter of the striking surface of the electronic drum 1 is not limited to 12 inches, and may be more than 12 inches or less than 12 inches.

[0043] The drum rim 6 is a member that fixes the sensor frame 4 and the drumhead 5 to the main body 2 and surrounds the outer periphery of the drumhead 5 to apply tension to the drumhead 5. The drum rim 6 is provided with a drum rim fitting 6a and a cover member 6b. The drum rim fitting 6a is a member for mounting the engaging bolt 7 described later. The cover member 6b is a member made of an elastic material such as rubber that covers the upper end of the drum rim fitting 6a. The cushioning effect of the elastic cover member 6b can reduce the striking sound of the drum rim 6 generated when the drum rim is struck.

[0044] The engagement bolts 7 are components for fixing the rim 6 to the main body 2. The engagement bolts 7 are provided in the same number as the engagement parts 3 provided on the main body 2, and are arranged at substantially the same intervals in the circumferential direction of the rim fitting 6a. When the engagement bolts 7 are screwed into the engagement parts 3, as described above, the rim 6 is fixed to the main body 2, and the rim 6 and the sensor frame 4 are connected via the drumhead 5, forming a transmission path for the vibration when the rim is struck to the rim sensor 9 described later.

[0045] A drum head sensor 8 and a drum edge sensor 9 are provided in the center of the sensor frame 4. The drum head sensor 8 is a sensor for detecting when the striking member 5a of the drum head 5 is struck, and includes a piezoelectric element. The drum head sensor 8 is provided in the upper center of the sensor frame 4. A buffer member 10 formed of an elastic member such as a sponge is inserted between the drum head sensor 8 and the striking member 5a of the drum head 5, and the vibration when the striking member 5a of the drum head 5 is struck by a drumstick or the like is transmitted to the drum head sensor 8 via the buffer member 10. And, the state of the transmitted vibration is detected by the drum head sensor 8. In addition, the drum head sensor 8 is not limited to being provided in the center of the sensor frame 4, that is, the center of the drum head 5, and can also be provided at a position offset from the center of the drum head 5 to the side of the main body 2, for example.

[0046] The rim sensor 9 is a sensor for detecting vibrations generated by hitting the rim 6, and includes a piezoelectric element similarly to the drumhead sensor 8. The rim sensor 9 is disposed at the lower center of the sensor frame 4. Since the sensor frame 4 is in contact with the rim 6 via the drumhead 5, the vibrations generated when the cover member 6b of the rim 6 is hit by a drumstick or the like are transmitted to the rim sensor 9 via the sensor frame 4, and the rim sensor 9 detects the state of the transmitted vibrations.

[0047] In addition, since the sensor frame 4 is also connected to the striking member 5a of the drumhead 5 and the main body 2, the vibration of the striking member 5a striking the drumhead 5 is transmitted to the sensor frame 4 directly or via the main body 2, and is detected by the drum edge sensor 9. Hereinafter, the "striking member 5a striking the drumhead 5" is referred to as "striking the drumhead 5", and similarly, the "cover member 6b striking the drum edge 6" is referred to as "striking the drum edge 6", etc. In addition, the drumhead sensor 8 and the drum edge sensor 9 are not limited to including piezoelectric elements, and may also include other components for detecting vibration.

[0048] In the electronic drum 1, a musical sound output when the drumhead 5 is struck is generated and output based on the position where the drumhead 5 is struck, i.e., the striking position, and the force Vc indicating the strength of the strike calculated when the drumhead 5 is struck. In the present embodiment, the force Vc used in generating such a musical sound is calculated using not only the output value of the drumhead sensor 8 that detects the vibration state of the drumhead 5 but also the output value of the drum rim sensor 9. Figure 2A to Figure 2C , describing the calculation method of the force Vc of this embodiment.

[0049] Figure 2A 1 is a diagram showing the output waveform hs1 and the output waveform rs1 of the drum head sensor 8 and the drum rim sensor 9 when the striking position is the center of the drum head 5 (diameter 12 inches). Figure 2B 1 is a diagram showing the output waveform hs2 and the output waveform rs2 of the drum head sensor 8 and the drum rim sensor 9 when the striking position is 70 mm from the center of the drum head 5 (diameter 12 inches). Figure 2C 1 and 2 are diagrams showing output waveforms hs3 and rs3 of the drumhead sensor 8 and the rim sensor 9 when the striking position is 140 mm from the center of the drumhead 5 (diameter 12 inches).

[0050] exist Figure 2A to Figure 2C Each figure shows the transition waveform of the output value outputted by the drumhead sensor 8 and the drum rim sensor 9 respectively when the same intensity is struck at each striking position of the drumhead 5. The output waveform of the drumhead sensor 8 is shown by a dotted line, and the output waveform of the drum rim sensor 9 is shown by a solid line.

[0051] Figure 2A The output waveform hs1 and the output waveform rs1 in FIG. 1 represent waveforms of output values ​​detected by the drumhead sensor 8 and the drum rim sensor 9 respectively when the striking position is the center of the drumhead 5, that is, directly above the drumhead sensor 8. Figure 2A In addition to these, the scanning time ScT, which is a predetermined period from the time when the impact is detected, is also shown. Figure 2B , Figure 2C middle.

[0052] In the present embodiment, "2 milliseconds" is set as the length of the scanning time ScT. In addition, the length of the scanning time ScT is not limited to 2 milliseconds, and may be greater than 2 milliseconds or less than 2 milliseconds. For example, the scanning time ScT may be set according to the size (diameter) of the drumhead 5 or the material of the drumhead 5, or the scanning time ScT may be set arbitrarily by the user. In addition, the detection of the start of the strike in the present embodiment uses existing technology, so a detailed description is omitted.

[0053] When the drumhead 5 is struck, first, the drumhead 5 is pressed downward by the strike, and the drumhead sensor 8 to which the press is transmitted via the buffer member 10 outputs a negative output value according to the amount of the press. After the output value Pv1 is detected at the peak value P1 at which the drumhead 5 is pressed to the bottom, the position of the drumhead 5 returns to the original position before the strike due to the restoring force of the striking member 5a including synthetic fibers. Along with this, the output value detected by the drumhead sensor 8 also increases after the peak value P1.

[0054] On the other hand, in the drum rim sensor 9, since there is a distance between the center of the drum head 5 which is the striking position and the sensor frame 4, the output waveform rs1 obtained by the drum rim sensor 9 gradually begins to change after a short period of time from the start of the change of the output waveform hs1 obtained by using the drum head sensor 8, and soon the amplitude of the output waveform rs1 becomes larger.

[0055] The waveform of the output waveform rs1 moves up and down frequently, in other words, the frequency of the output waveform rs1 is higher than the frequency of the output waveform hs1 obtained by the drumhead sensor 8. The reason for this is that the transmission path from the drumhead 5 to the drum rim sensor 9, that is, the rigidity of the drum rim 6, the sensor frame 4, and the main body 2 is higher than that of the striking member 5a whose vibration is detected by the drumhead sensor 8. In addition, the drumhead sensor 8 and the drum rim sensor 9 are sensors that are set to output positive or negative output values, but are not limited to this, and may also be sensors that output only positive values.

[0056] Next, if Figure 2B As shown in FIG. 1 , when the striking position is outside the center of the drumhead 5, that is, 70 mm from the center of the drumhead 5, the output waveforms hs2 and rs2 obtained by the drumhead sensor 8 and the drum rim sensor 9 are similar to the output waveforms hs1 and rs2, respectively. Figure 2A In the case of being further away from the drum head sensor 8, the output value Pv2 detected at the peak value P2 of the output waveform hs2 is greater than that in the Figure 2A The output value Pv1 detected from the peak value P1 of the output waveform hs1 is small.

[0057] On the other hand, due to Figure 2B The striking position in Figure 2A In the case of the drum edge sensor 9, the drum edge sensor 9 is closer to the sensor frame 4, so the moment when the vibration starts to be detected and the output waveform rs2 starts to change is shorter than Figure 2A The output waveform rs1 is early.

[0058] like Figure 2CAs shown in the figure, when the striking position is further outward, that is, 140 mm from the center of the drum head 5, the output waveforms hs3 and rs3 obtained by the drum head sensor 8 and the drum edge sensor 9 are similar to the output waveforms hs1, hs2 and rs1, rs2, respectively. Figure 2B In the case of being further away from the drum head sensor 8, the output value Pv3 detected at the peak P3 of the output waveform hs3 is greater than that in the Figure 2B The output value Pv2 detected from the peak value P2 of the output waveform hs2 is small.

[0059] On the other hand, due to Figure 2C The striking position in Figure 2B In the case of the drum edge sensor 9, the drum edge sensor 9 is closer to the sensor frame 4, so the moment when the vibration starts to be detected and the output waveform rs3 starts to change is shorter than Figure 2B The output waveform of rs2 is early.

[0060] Conventionally, the maximum value of the amplitude detected by the drumhead sensor 8 within the scanning time ScT, i.e. Figure 2A to Figure 2C The force Vc is calculated based on the output value Pv1 to the output value Pv3 of the peak value P1 to the peak value P3 in the drumhead 5. However, as described above, even when the drumhead 5 is struck with the same intensity, the farther the distance between the striking position and the drumhead sensor 8 is, the smaller the output value of the drumhead sensor 8 is. That is, the farther the distance between the striking position and the drumhead sensor 8 is, the lower the sensitivity of the drumhead sensor 8 to the strike is. If the force Vc is calculated based on the output value of the drumhead sensor 8, then even when the drumhead 5 is actually struck with the same intensity, the force Vc that is smaller as the distance between the striking position and the drumhead sensor 8 is greater will be calculated, and therefore the accuracy of the calculated force Vc will be reduced.

[0061] Here, the output waveform of the drum edge sensor 9 is as follows: Figure 2A to Figure 2C As shown, since the farther the striking position is from the drum head sensor 8, the earlier the detection of the start of the striking of the drum head 5 is, it can be said that the output value of the drum edge sensor 9 detected during the scanning time ScT accurately reflects the striking condition of the peripheral part of the drum head 5 away from the drum head sensor 8.

[0062] Therefore, in this embodiment, the output value of the drum head sensor 8 and the output value of the drum rim sensor 9 are combined to calculate the force Vc when the drum head 5 is struck. Specifically, the maximum value of the absolute value of the output value detected by the drum head sensor 8 during the scanning time ScT from the detection of the start of striking the drum head 5, that is, Figure 2A to Figure 2CThe absolute values ​​of the output values ​​Pv1 to Pv3 detected by the peak values ​​P1 to P3 are set as the peak value Ph, and the energy of the output value detected by the drum edge sensor 9 during the specified period within the scanning time ScT, that is, the energy calculation period, is set as the energy value Er, and the force Vc is calculated by the following formula 1.

[0063] [Number 1]

[0064] Vc=Ph+α·Er…(Formula 1)

[0065] That is, the force Vc is calculated by adding the peak value Ph of the drum head sensor 8 to the multiplication value of the weighting coefficient α and the energy value Er of the drum edge sensor 9. Here, the energy value Er of the output value of the drum edge sensor 9 is a value obtained by adding the absolute values ​​of the output values ​​detected by the drum edge sensor 9 during the energy calculation period during the scanning time ScT, that is, the integral value of the absolute values ​​of the output values ​​detected by the drum edge sensor 9. Here, the "energy calculation period" is a period set according to the size of the diameter of the drum head 5, for example, the period from the start of the strike to 1 millisecond after the start of the strike during the scanning time ScT can be listed. In addition, α multiplied by the energy value Er is a weighting coefficient, and its value varies according to the striking position of the drum head 5. Regarding the weighting coefficient α, it will be used Figure 4A to Figure 4C This will be described later.

[0066] In this way, the force Vc is calculated based on the energy value Er of the rim sensor 9 in addition to the peak value Ph of the drum head sensor 8. The rim sensor 9 detects the vibration of the rim 6 or the main body 2 on which the drum head 5 is provided, and therefore has a higher sensitivity to the peripheral portion of the drum head 5 being struck than the drum head sensor 8. By using the energy value Er of the rim sensor 9 for calculating the force Vc, the accuracy of the force Vc calculated for the peripheral portion of the drum head 5 being struck can be improved.

[0067] The energy value Er of the drum edge sensor 9 used in the calculation of the force Vc is an integrated value obtained by adding the absolute values ​​of the output values ​​of the drum edge sensor 9. Figure 2A to Figure 2C As shown, the output waveforms rs1 to rs3 of the drum rim sensor 9 have a higher frequency than the output waveforms hs1 to hs3 of the drum head sensor 8, and are in a form of frequent up and down movement. Therefore, if the output value of the drum rim sensor 9 is directly added, the positive and negative values ​​of the output values ​​cancel each other out, and the striking condition detected by the drum rim sensor 9 cannot be accurately represented.

[0068] Therefore, by setting the energy value Er of the drum rim sensor 9 to the integrated value obtained by adding the absolute values ​​of the output values ​​of the drum rim sensor 9, the magnitude of the output value can be reflected in the energy value Er regardless of whether the detection value is positive or negative, thereby accurately reflecting the striking condition detected by the drum rim sensor 9.

[0069] Furthermore, this energy value Er is generally a value proportional to the square of the amplitude of the output waveform rs1 to the output waveform rs3 (i.e., the magnitude of the output value), and therefore is also a value reflecting the strength of the hit at the peripheral portion of the drumhead 5 (i.e., the magnitude of the amplitude of the output waveform rs1 to the output waveform rs3). Thus, the strength of the hit on the drumhead 5 is accurately reflected in the energy value Er, thereby also improving the accuracy of the calculated force Vc.

[0070] As such a sensor for detecting the hit on the peripheral portion of the drumhead 5, a rim sensor 9 for detecting the hit on the drum rim 6 (rim hit) is used. That is, the rim sensor 9 can detect not only the rim hit but also the hit on the peripheral portion of the drumhead 5, so even if the number of sensors mounted on the electronic drum 1 is minimized (in this embodiment, the drumhead sensor 8 and the rim sensor 9 are two), the calculation of the force Vc of the hit on the drumhead 5 and the detection of the rim hit can be realized with high accuracy.

[0071] In addition, by using the peak value Ph of the drumhead sensor 8 in the calculation of the force Vc as before, it is also possible to calculate with high accuracy the force Vc based on the strike to the center of the drumhead 5. In this way, by calculating the force Vc by combining the peak value Ph of the drumhead sensor 8 with the energy value Er of the rim sensor 9, it is possible to calculate with high accuracy the force Vc over the entire area of ​​the drumhead 5 struck by a drumstick or the like.

[0072] Next, refer to Figure 3 , explaining the function of the electronic drum 1. Figure 3 2 is a functional block diagram of the electronic drum 1. The electronic drum 1 includes a drumhead result acquisition unit 200, a shell result acquisition unit 201, and a force calculation unit 202.

[0073] The drumhead result acquisition unit 200 is a unit that acquires the detection result (output value) from the drumhead sensor 8. Figure 4A The shell result acquisition unit 201 is a unit for acquiring the detection result (output value) from the drum edge sensor 9, and is implemented by the CPU 20. The force calculation unit 202 is a unit for calculating the force Vc when the drum head 5 is struck based on the detection result acquired by the drum head result acquisition unit 200 and the detection result acquired by the shell result acquisition unit 201, and is implemented by the CPU 20.

[0074] In the electronic drum 1, the force Vc when the drumhead 5 is struck is calculated based on the detection result from the drumhead sensor 8 and the detection result from the rim sensor 9. The rim sensor 9 detects the vibration of the main body 2 on which the drumhead 5 is provided, and therefore has a higher sensitivity to the peripheral portion of the drumhead 5 being struck than the drumhead sensor 8. By using the detection result from such a rim sensor 9 for calculating the force Vc, the accuracy of the force Vc for the peripheral portion of the drumhead 5 being struck can be improved.

[0075] Next, refer to Figure 4A to Figure 4C , describing the electrical structure of the electronic drum 1. Figure 4A 1 is a block diagram showing the electrical structure of the electronic drum 1. The electronic drum 1 has a CPU 20, a flash read only memory (ROM) 21, and a random access memory (RAM) 22, which are connected via a bus 23. In addition, the drum head sensor 8 and the drum edge sensor 9 and the external input / output terminal 24 are also connected to the bus 23. The external input / output terminal 24 is connected to a sound source 25. The sound source 25 is connected to an amplifier 26, and the amplifier 26 is connected to a speaker 27.

[0076] The CPU 20 is a computing device that controls each unit connected via a bus 23. The flash ROM 21 is a rewritable nonvolatile storage device that stores programs executed by the CPU 20 and fixed value data, and includes a control program 21a and drum edge coefficient data 21b. When the CPU 20 executes the control program 21a, the execution Figure 5 The drum edge coefficient data 21b is stored with Figure 2A to Figure 2C Here, refer to the data table of weighting coefficient α described in Figure 4B , Figure 4C , explaining the drum edge coefficient data 21b.

[0077] Figure 4B is a diagram schematically showing the drum edge coefficient data 21b. Figure 4C is a graph showing the relationship between the hitting position and the weighting coefficient α. Figure 4B As shown, the rim coefficient data 21b stores weighting coefficients α corresponding to the striking positions of the drumhead 5. As the "striking position of the drumhead 5" in the rim coefficient data 21b, the distance between the striking position and the center of the drumhead 5 (indicated as "distance from the center of the drumhead" in the figure) is used.

[0078] like Figure 4CAs shown, the relationship between the striking position and the weighting coefficient α stored in the rim coefficient data 21b is that the weighting coefficient α increases as the striking position moves away from the center of the drumhead 5. That is, the value of the weighting coefficient α output by the weighting function, which is a function having the striking position as input, is stored in the rim coefficient data 21b.

[0079] More specifically, the weighting coefficient α output by the weighting function is divided into a first interval α1, a second interval α2, and a third interval α3 according to the striking position. The first interval α1 is an interval of the central part of the drumhead 5 within the range of the striking position from the center of the drumhead 5 to the position ra (for example, a position 20 mm from the center of the drumhead 5). In the first interval α1, the weighting coefficient α is always "0". That is, by the formula 1, the force Vc is calculated only based on the peak value Ph of the drumhead sensor 8. Thus, by calculating the force Vc of the strike at the central part of the drumhead sensor 8 only using the drumhead sensor 8 with good sensitivity at the striking position, the force Vc with good accuracy can be calculated.

[0080] The second interval α2 is an interval of the middle part of the drum head 5 within the range of the striking position from the position ra to the position rb (for example, a position 40 mm from the center of the drum head 5), and in this interval, the weighting coefficient α increases in proportion to the distance from the center of the drum head 5. That is, in the second interval α2 of the weighting function, the relationship between the distance from the center of the drum head 5 and the weighting coefficient α is a linear relationship.

[0081] Therefore, even if the sensitivity of the drum head sensor 8 to the strike decreases and the peak value Ph decreases because the striking position is away from the center of the drum head 5, the energy value Er of the drum edge sensor 9 which is highly sensitive to the strike at the peripheral portion of the drum head 5 is added in the calculation of the force Vc, and the energy value Er is multiplied by the weighting coefficient α which increases as the striking position is away from the center of the drum head 5. Therefore, the accurate force Vc can also be calculated in the second interval α2.

[0082] The third interval α3 is an interval of the peripheral portion of the drumhead 5 where the striking position is greater than the position rb, and in this interval, the weighting coefficient α increases in proportion to the distance from the center of the drumhead 5, following the second interval α2. In the third interval α3 of the weighting function, the relationship between the distance from the center of the drumhead 5 and the weighting coefficient α is a linear relationship, but the slope is set smaller than that in the second interval α2.

[0083] The reason for this is that the difference between the output value of the drumhead sensor 8 when striking at the striking position A3 in the third interval α3 and the output value of the drumhead sensor 8 when striking at the striking position B3 after moving 10 mm from the striking position A3 to the outside in the radial direction of the drumhead 5 is smaller than the difference between the output value of the drumhead sensor 8 when striking at the striking position A2 in the second interval α2 and the output value of the drumhead sensor 8 when striking at the striking position B2 after moving 10 mm from the striking position A2 to the outside in the radial direction of the drumhead 5 (in addition, the striking position B2 is also in the second interval α2). In other words, the drop in the sensitivity of the drumhead sensor 8 is smaller in the third interval α3 than in the second interval α2.

[0084] In this way, by considering the characteristics of the output value of the drumhead sensor 8 relative to the striking position in the slope of the weighting function, the energy value Er of the drum edge sensor 9 can be used to supplement the peak value Ph of the drumhead sensor 8 in the calculation of the force Vc, so that the force Vc can be calculated with high accuracy without relying on the striking position of the drumhead 5.

[0085] The shape of the weighting function of this embodiment, i.e., position ra, position rb, or the slope of the weighting function, is set in advance based on experiments. In addition, position ra, position rb, or the slope of the weighting function is not limited to the above, and other positions or slopes may be used, for example, according to the size or material of the drumhead 5, the material of the main body 2 or the sensor frame 4, etc.

[0086] In addition, the intervals of the weighting function are set to three, α1 to α3, but the intervals are not limited to this, and the intervals may be less than or equal to three. Furthermore, although the relationship between the hitting position and the weighting coefficient α in the weighting function is set to be linear, the relationship is not limited to this. The relationship between the hitting position and the weighting coefficient α in the weighting function may be set to be nonlinear such as a quadratic function or an exponential function, or the weighting coefficient α may be changed in a step-like manner relative to the hitting position.

[0087] Back to Figure 4A The RAM 22 is a memory for storing various work data or flags in a rewritable manner when the CPU 20 executes a program, and is provided with a drum head annular buffer 22a, a drum edge annular buffer 22b, a peak value memory 22c for storing the peak value Ph, an energy value memory 22d for storing the energy value Er, a striking position memory 22e for storing the striking position, and a force memory 22f for storing the force Vc.

[0088] The drumhead annular buffer 22a is a buffer that stores only the output values ​​of the drumhead sensor 8 for the past 5 milliseconds. The output values ​​of the drumhead sensor 8 are stored in the drumhead annular buffer 22a in the order in which they are input. When a new output value of the drumhead sensor 8 is input while the output values ​​of the drumhead sensor 8 for 5 milliseconds are stored in the drumhead annular buffer 22a, the oldest output value among the output values ​​stored in the drumhead annular buffer 22a is deleted, and then the newly input output value is added to the drumhead annular buffer 22a.

[0089] The drum edge annular buffer 22b is a buffer that stores only the output values ​​of the drum edge sensor 9 for the past 5 milliseconds. The output values ​​of the drum edge sensor 9 are also stored in the drum edge annular buffer 22b in the order in which they are input. When a new output value of the drum edge sensor 9 is input while the output values ​​of the drum edge sensor 9 for 5 milliseconds are stored in the drum edge annular buffer 22b, the oldest output value among the output values ​​stored in the drum edge annular buffer 22b is deleted, and then the newly input output value is added to the drum edge annular buffer 22b.

[0090] The period during which the drum head annular buffer 22a and the drum edge annular buffer 22b can store output values ​​is not limited to 5 milliseconds, and may be less than 5 milliseconds or more than 5 milliseconds as long as it is greater than the scanning time ScT (2 milliseconds in this embodiment).

[0091] The external input / output terminal 24 is an interface for transmitting and receiving data to and from a sound source 25 or other computers described later. An instruction to generate musical sounds to be generated by the electronic drum 1 is sent to the sound source 25 via the external input / output terminal 24 .

[0092] The sound source 25 is a device that controls the timbre or various effects of musical sounds (percussion sounds) according to instructions from the CPU 20, and has a built-in digital signal processor (DSP) 25a that performs calculations such as filtering and effects on waveform data. The musical sound processed by the sound source 25 is output as an analog musical sound signal. The amplifier 26 is a device that amplifies the analog musical sound signal output by the sound source 25, and outputs the amplified analog musical sound signal to the speaker 27. The speaker 27 outputs the analog musical sound signal amplified by the amplifier 26 as musical sound.

[0093] Next, refer to Figure 5 , describing the processing executed by the CPU 20. Figure 51 is a flowchart of the main process. The main process is a process executed by the CPU 20 after the power of the electronic drum 1 is turned on. In the main process, first, the output value is obtained from the drum head sensor 8 and added to the drum head ring buffer 22a, and the output value is obtained from the drum edge sensor 9 and added to the drum edge ring buffer 22b (S1). After the processing of S1, it is confirmed whether the time from the detection of the start of hitting the drum head 5, that is, the elapsed time, is counted (S2).

[0094] In the process of S2, when the elapsed time is not counted (S2: No), the drum head annular buffer 22a and the drum edge annular buffer 22b are referenced to confirm whether the start of the strike is detected by the drum head sensor 8 or the drum edge sensor 9 (S3). In addition, the existing technology is used for detecting the start of the strike in the process of S3, so the description is omitted. In the process of S3, when the start of the strike is detected (S3: Yes), the timing of the elapsed time is started from 0 (S4).

[0095] In the process of S2, when the elapsed time is counted (S2: Yes), it is confirmed whether the elapsed time is greater than the scanning time ScT (2 milliseconds) (S5). In the process of S5, when the elapsed time is greater than the scanning time ScT (S5: Yes), the maximum value of the absolute value of the output value added during the scanning time ScT from the start of the elapsed time counting among the output values ​​stored in the drum head ring buffer 22a, that is, the peak value Ph, is obtained and stored in the peak value memory 22c (S6).

[0096] After the processing of S6, the output values ​​stored in the drum edge ring buffer 22b are calculated for the period of the scanning time ScT from the start of the elapsed time counting. Figure 2A to Figure 2C The value obtained by integrating (adding) the absolute values ​​of the output values ​​added during the energy calculation period described in the above is the energy value Er, and is stored in the energy value memory 22d (S7).

[0097] After the processing of S7, the striking position of the drumhead 5 is calculated with reference to the drumhead annular buffer 22a and the drum edge annular buffer 22b, and is stored in the striking position memory 22e (S8). In addition, the calculation of the striking position in the processing of S8 also uses existing technology, so the description is omitted. After the processing of S8, the weighting coefficient α corresponding to the striking position in the striking position memory 22e is obtained from the drum edge coefficient data 21b (S9).

[0098] After the processing of S9, the value obtained by adding the multiplication value of the weighting coefficient α obtained in the processing of S9 and the energy value Er in the energy value memory 22d to the peak value Ph in the peak value memory 22c, that is, the force Vc is calculated and stored in the force memory 22f (S10).

[0099] After the process of S10, the instruction to generate the musical sound corresponding to the force stored in the force memory 22f and the striking position stored in the striking position memory 22e is output to the sound source 25 (S11). In the sound source 25, the musical sound instructed by the CPU 20 is generated and output to the amplifier 26, and the musical sound generated by the speaker 27 connected to the amplifier 26 is output. When the start of striking is not detected in the process of S3 (S3: No), when the elapsed time is less than the scanning time ScT in the process of S5 (S5: No), or after the processes of S4 and S11, the processes from S1 onwards are repeated.

[0100] Although the above description has been given based on the above-mentioned embodiment, it can be easily estimated that various improvements and changes can be made.

[0101] In the above embodiment, the rim sensor 9 is used to detect the impact on the peripheral portion of the drumhead 5, but the present invention is not limited thereto. For example, a sensor for detecting the vibration of the main body 2 may be added independently of the rim sensor 9, and the force Vc may be calculated based on the output value of the impact on the drumhead 5 detected by the sensor.

[0102] In the above-described embodiment, the drum head sensor 8 and the drum edge sensor 9 are disposed adjacently on the sensor frame 4 which is the same component, but the present invention is not limited thereto. For example, in order to suppress the vibration detected by the drum edge sensor 9 from entering the drum head sensor 8, a distance may be provided between the position where the drum head sensor 8 is provided and the position where the drum edge sensor 9 is provided in the sensor frame 4, or a component that blocks the vibration from propagating to each other may be provided between the drum head sensor 8 and the drum edge sensor 9 in the sensor frame 4. In addition, instead of providing the drum head sensor 8 and the drum edge sensor 9 in the same sensor frame 4, they may be provided in different frames.

[0103] In the above-described embodiment, one drum head sensor 8 and one drum edge sensor 9 are provided respectively, but the present invention is not limited thereto. More than two drum head sensors 8 may be provided, and more than two drum edge sensors 9 may be provided. When a plurality of drum head sensors 8 are provided, as the peak value Ph used in the calculation of the force Vc in Formula 1, for example, the average value of the peak values ​​detected by each drum head sensor 8 may be used, or a weighted average value obtained by multiplying the peak values ​​of each drum head sensor 8 by the corresponding weighting coefficient and averaging these multiplication values ​​may be used.

[0104] In addition, when multiple drum rim sensors 9 are provided, as the energy value Er used in the calculation of the force Vc in Formula 1, for example, the average value of the energy values ​​calculated based on the output values ​​of each drum rim sensor 9 may be used, or the weighted average value of the energy values ​​calculated based on the output values ​​of each drum rim sensor 9 may be used.

[0105] In the above-described embodiment, the force Vc is calculated based on the peak value Ph of the drum head sensor 8 and the energy value Er of the drum rim sensor 9, but the present invention is not limited thereto. For example, in the calculation of the force Vc, the energy value of the drum head sensor 8 which is the same as the energy value Er of the drum rim sensor 9 may be used instead of the peak value Ph of the drum head sensor 8. In addition, in the calculation of the force Vc, the peak value of the drum rim sensor 9 which is the same as the peak value Ph of the drum head sensor 8 may be used instead of the energy value Er of the drum rim sensor 9.

[0106] In addition, the energy value Er of the drum edge sensor 9 is set to an integral value obtained by adding the absolute values ​​of the output values ​​of the drum edge sensor 9, but the present invention is not limited thereto. For example, the energy value Er of the drum edge sensor 9 may be set to an average value of the absolute values ​​of the output values ​​of the drum edge sensor 9, or may be set to a median value of the absolute values ​​of the output values ​​of the drum edge sensor 9, or other statistical indicators related to the output values ​​of the drum edge sensor 9 may be used.

[0107] In the above-described embodiment, the weighting coefficient α is set to a value greater than 0 (see Figure 4B ), but is not limited thereto. The weighting coefficient α may also be set to a value smaller than 0. For example, by Figure 4B The weighting coefficient α of the first interval α1 is set to a value smaller than 0, and in Formula 1, it is obtained by subtracting the energy value Er of the drum edge sensor 9 from the peak value Ph of the drum head sensor 8. Therefore, even if the output value of the drum head sensor 8 becomes too large due to the strike to the center of the drum head 5 to which the drum head sensor 8 is highly sensitive, the excess portion can be corrected by subtracting the energy value Er of the drum edge sensor 9, so that the force Vc with high accuracy can be calculated.

[0108] In addition, in the calculation of the force Vc, the energy value Er of the drum rim sensor 9 is multiplied by the weighting coefficient α, but the present invention is not limited to this. For example, the weighting coefficient α may be added to the energy value Er of the drum rim sensor 9, the weighting coefficient α may be subtracted from the energy value Er, or the energy value Er may be divided by the weighting coefficient α. In these cases, the weighting coefficient α may be set so that the force Vc can be appropriately calculated when the energy value Er is added.

[0109] Alternatively, the peak value Ph of the drumhead sensor 8 may be multiplied by a weighting coefficient α. The weighting coefficient α at this time may be set so that the force Vc can be appropriately calculated when multiplied by the peak value Ph. Figure 4CThe weighting coefficient α is set by the inverse function of the weighting function.

[0110] In the above embodiment, the electronic drum 1 simulating a drum is exemplified as an electronic percussion instrument, but the present invention is not limited thereto and can also be applied to simulating other percussion instruments such as a bass drum, a snare drum, a tom drum, etc. In addition, the control program 21a can also be executed by other information processing devices (computers) such as personal computers or portable terminals.

[0111] In the above embodiment, the drum head sensor 8 and the drum edge sensor 9 are provided on the electronic drum 1, and the force Vc is calculated based on the output values ​​of the drum head sensor 8 and the drum edge sensor 9, but the present invention is not limited thereto. Figure 6 As shown, the control device 50 may be connected to a drum 60 as a percussion instrument provided separately from the control device 50 , and the force Vc corresponding to the strike on the drum 60 may be calculated in the control device 50 .

[0112] More specifically, the control device 50 is provided with a CPU 51, a flash ROM 52, a RAM 53, a bus 54, and an external input / output terminal 55, each of which has a corresponding Figure 4A to Figure 4C The CPU 20, flash ROM 21, RAM 22, bus 23 and external input / output terminals 24 (see Figure 2A ) have the same functions.

[0113] The drum 60 is provided with a drum head sensor 61 for detecting the striking surface of the drum 60 being struck, and a drum edge sensor 62 for detecting the vibration generated by the striking of the drum edge of the drum 60. The drum head sensor 61 and the drum edge sensor 62 are connected to the external input / output terminal 55 of the control device 50, and the output values ​​from the drum head sensor 61 and the drum edge sensor 62 are input to the control device 50 via the external input / output terminal 55.

[0114] Thus, on the basis of configuring the control device 50 and the drum 60, by executing the Figure 5 At this time, in the main processing such as S1, instead of using the output values ​​of the drum head sensor 8 and the drum rim sensor 9 from the electronic drum 1, the output values ​​from the drum head sensor 61 and the drum rim sensor 62 input from the external input / output terminal 55 can be used.

[0115] In addition, you can also Figure 6The control device 50 is connected to an electronic percussion instrument such as an electronic drum 1 instead of the drum 60, and the control device 50 calculates the force Vc. In the above case, the external input / output terminal 24 of the electronic drum 1 is connected to the external input / output terminal 55 of the control device 50, the output values ​​of the drum head sensor 8 and the drum edge sensor 9 are output from the external input / output terminal 24 of the electronic drum 1, and the output values ​​of the drum head sensor 8 and the drum edge sensor 9 input from the external input / output terminal 55 are used in the control device 50 to perform Figure 5 The main processing can be.

Claims

1. An electronic percussion instrument, characterized in that: include: case; a drumhead, disposed on the shell, constituting a striking surface; a drumhead sensor for detecting a strike on the drumhead; a housing sensor for detecting vibration of the housing; a drumhead result obtaining unit, for obtaining a detection result from the drumhead sensor; a shell result acquisition unit, which acquires the detection result from the shell sensor; as well as The force calculation unit calculates the force of the drumhead when it is struck based on the detection result obtained by the drumhead result acquisition unit and the detection result obtained by the shell result acquisition unit.

2. The electronic percussion instrument according to claim 1, wherein: The force calculation unit calculates the force using an energy value based on a waveform of the detection result acquired by the shell result acquisition unit.

3. The electronic percussion instrument according to claim 2, wherein: The energy value of the waveform is a value obtained by integrating the detection results acquired by the shell result acquisition unit within a predetermined scanning time.

4. The electronic percussion instrument according to any one of claims 1 to 3, characterized in that: include: a striking position detection unit for detecting a striking position on the drumhead; a weighting coefficient acquiring unit that acquires a weighting coefficient for the detection result acquired by the shell result acquiring unit, corresponding to the struck position acquired by the struck position detecting unit; The force calculation unit calculates the force of the drumhead being struck based on the detection result acquired by the drumhead result acquisition unit, the detection result acquired by the shell result acquisition unit, and the weighting coefficient acquired by the weighting coefficient acquisition unit.

5. The electronic percussion instrument according to claim 4, wherein: The force calculation unit calculates the force of the drumhead being struck based on the detection result obtained by the drumhead result acquisition unit and a value obtained by multiplying the detection result obtained by the shell result acquisition unit by the weighting coefficient obtained by the weighting coefficient acquisition unit.

6. The electronic percussion instrument according to claim 4, wherein: The weighting coefficient acquisition unit acquires a weighting coefficient based on an output of a weighting function that is a function that outputs the corresponding weighting coefficient according to the input hitting position. The weighting function is a function of a weighting coefficient that outputs a larger value as the input striking position moves from the center of the drumhead toward the periphery.

7. The electronic percussion instrument according to claim 6, wherein: In the weighting function, the relationship between the hitting position and the weighting coefficient is a linear relationship.

8. The electronic percussion instrument according to claim 1, wherein: A rim is provided on the shell so as to surround the drumhead. The shell sensor detects a strike to the rim.

9. The electronic percussion instrument according to claim 1, wherein: The drumhead sensor is arranged at the center of the drumhead.

10. A control device for controlling a sound source unit based on a detection result from a drumhead sensor, the drumhead sensor detecting a strike to a drumhead constituting a striking surface of a percussion instrument, and a detection result from a shell sensor detecting vibration of a shell of the percussion instrument, the control device comprising: a drumhead result obtaining unit, for obtaining a detection result from the drumhead sensor; a shell result acquisition unit, which acquires the detection result from the shell sensor; as well as The force calculation unit calculates the force of the drumhead when it is struck based on the detection result obtained by the drumhead result acquisition unit and the detection result obtained by the shell result acquisition unit.

11. A computer-readable storage medium storing a force calculation program for causing a computer to execute a force calculation process for calculating force, wherein the force calculation program is characterized in causing the computer to execute the following steps: a drumhead result obtaining step of obtaining a detection result from a drumhead sensor that detects a strike on a drumhead constituting a striking surface of the percussion instrument; a shell result obtaining step of obtaining a detection result from a shell sensor, the shell sensor detecting vibration of the shell of the percussion instrument; and A force calculation step calculates the force of the strike based on the detection result obtained by the drumhead result acquisition step and the detection result obtained by the shell result acquisition step.

12. A force calculation method, characterized in that: include: a drumhead result obtaining step of obtaining a detection result from a drumhead sensor that detects a strike on a drumhead constituting a striking surface of the percussion instrument; a shell result obtaining step of obtaining a detection result from a shell sensor, wherein the shell sensor detects vibration of the shell of the percussion instrument; as well as A force calculation step calculates the force of the strike based on the detection result obtained by the drumhead result acquisition step and the detection result obtained by the shell result acquisition step.

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