JP4218620B2 - Keyboard instrument - Google Patents

Description

  The present invention relates to a keyboard instrument such as a piano, and more particularly to a technique for sensing some motion related to a performance operation and determining a stringing timing based on the detection result.

Conventionally, in a keyboard instrument such as an auto-playing piano, movements of keys and hammers are detected by a sensor, and the detection results are recorded as performance data or supplied to an electronic sound source to generate musical sounds electronically. Has been done. In such an automatic performance piano, when creating performance data etc. using the stringing timing and stringing speed, it is necessary to obtain a more accurate stringing timing and stringing speed. A device provided with a hammer sensor is known. In Patent Document 1 below, as an example of a keyboard instrument having a hammer sensor, a continuous quantity sensor that continuously detects the displacement of the hammer shank is provided, and a physical quantity (position, speed, or (Acceleration) is continuously detected, and using the detection result, (1) hammer operation start timing, (2) string-striking timing, (3) hammer speed immediately before string-striking, (4) key-pressing timing, (5 ) Back check timing, (6) Back check release timing, (7) Hammer speed after back check release, (8) Damper return timing, (9) Hammer operation end timing, (10) Key release timing, etc. An apparatus is disclosed that acquires various information related to performance. This is by continuously detecting physical quantities related to the movement of the hammer, appropriately converting the detected sensor output, obtaining various information as described above, and creating performance data based on the various information, It was possible to create performance data capable of reproducing performance with higher accuracy.
JP 2001-175262 A

  According to the conventional apparatus configuration represented by the above-mentioned Patent Document 1, for example, when generating information on stringing timing, hammer speed information immediately before stringing, etc., the output from the continuous quantity sensor and a predetermined reference value are used. Based on the comparison, the presence / absence of string striking is determined, and the determination result is used to generate information on the timing of striking, hammer speed information immediately before striking, and the like. As described above, since the above-described various information is generated based on the sensor output from the continuous quantity sensor and the predetermined reference value, when the input / output characteristics of the sensor change due to temperature change, deterioration with time, etc., The various information to be generated does not accurately correspond to the actual performance state (hammer operation state), and the output information is inaccurate.

  The present invention has been made in view of the above points, and is a keyboard capable of performing an accurate string determination even if the sensor output characteristics have changed due to changes in the temperature of the LEDs or changes in the action mechanism over time. The purpose is to provide a musical instrument.

  The keyboard instrument according to the present invention includes an operating element, a driven member that is driven in accordance with the operation of the operating element and that contacts another member in accordance with the driving, and a detecting unit that detects the movement of the driven member. And an estimation means for estimating that the driven member is in contact with the other member based on a detection output of the detection means and a predetermined reference value for estimation, and generating estimation information related to the contact. Determining means for determining that the driven member has reached a contact position with another member, and correcting means for correcting the determination of the estimating means according to the determination result of the determining means.

  According to this, the estimation means estimates based on the detection output of the detection means and the reference value for estimation based on the fact that the driven member is in contact with another member, and the estimation information relating to the contact It is estimated that the driven member has come into contact with another member in substantially real time. The determination means determines that the driven member has actually reached a contact position with another member. Then, the correcting means corrects the judgment of the estimating means according to the judgment result of the judging means. More specifically, the correcting means includes at least the output of the detecting means and the reference value for estimation in the estimating means. By calibrating one of them, the judgment of the estimation means is corrected, and the estimation information generated by the estimation means is made more reliable. As a result, there is an excellent effect that it is possible to perform accurate string striking determination regardless of a change in detection output due to a change in action mechanism over time.

An embodiment of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a diagram for explaining a configuration example of an automatic performance piano according to one embodiment of the present invention, in which a main part of a mechanical sounding mechanism is extracted and shown, and a functional block of an electric control system Indicates. As shown in FIG. 1, the automatic performance piano has a mechanical sound generation mechanism for transmitting a key 1, a hammer 2 that rotates in conjunction with the key 1, and a movement of the key 1 to the hammer 2. An action mechanism 3, a string 4 struck by the hammer 2, an electromagnetic solenoid 5 that drives the key 1 based on electrical control, and a damper 6 that stops vibration of the string 4. These configurations are the same as those of a general automatic performance piano. As will be described later, in this embodiment, a configuration for servo-controlling the drive of the electromagnetic solenoid 5 is applied, and the solenoid 5 is provided with a feedback sensor (not shown) for detecting the operation of the plunger. Shall.
Further, the automatic performance piano is provided with a back check 7 as in the case of a normal acoustic piano. The back check 7 is a member for preventing the hammer 2 from being ramped up due to a reaction during stringing. In addition to the above, the automatic performance piano includes various components similar to those of a normal acoustic piano, but description and illustration thereof are omitted. The hammer 2 is connected to the action mechanism 3 through the hammer shank 2a so as to be rotatable about the operation fulcrum 2b. When the corresponding key 1 is non-pressed (a state in which no external force is applied), In the rest position (position of stroke amount 0 mm) as shown in FIG. The hammer 2 basically makes a rotation stroke between the rest position and a predetermined end position in conjunction with the performance operation (vertical swing) of the corresponding key 1. In this embodiment, the end position of the hammer 2 is a position where the hammer 2 is displaced by 48 mm from the rest position. In FIG. 1, the hammer 2 positioned at the end position is indicated by a dotted line.

In FIG. 1, reference numeral 26 denotes a sensor that detects the displacement of the hammer 2 in a continuous amount, and the signal processing unit 27 is a module that takes in an output signal from the sensor 26 and performs various processes on the output signal. is there.
As the sensor 26, for example, an optical position sensor capable of outputting continuous position information of the hammer 2 may be applied. A configuration example of an optical sensor suitable for detecting the continuous position of the hammer 2 will be briefly described. The optical sensor is connected by, for example, a light emitting side sensor head connected by an LED and an optical fiber, a photodiode and an optical fiber. A light-receiving side sensor head, and the light from the LED is emitted from the light-emitting side sensor head, received by the light-receiving side sensor head connected to the photodiode by an optical fiber, and an output voltage corresponding to the amount of light received is extracted by the photodiode. be able to. By configuring so that the amount of light received by the light receiving side sensor head changes corresponding to the displacement of the movable member (in this example, the hammer 2), the output voltage corresponding to the stroke position of the hammer 2 is used as the output of the sensor. Obtainable. Various configurations for changing the amount of light received by the light receiving side sensor head in accordance with the displacement of the hammer 2 have been conventionally known. As an example, it is possible to apply light emitted from an LED to a reflecting plate on which a gray scale is formed, and the reflected light from the reflecting plate is received by a light receiving side sensor head (photodiode). According to this, since the displacement of the received light amount in the light receiving side sensor head exhibits an increase / decrease characteristic according to the grayscale shading pattern, it is possible to obtain an arbitrary output characteristic according to the pattern as the sensor output, There is an advantage that analog data showing (proportional) linear characteristics with respect to the displacement of the hammer 2 can be obtained as an output signal of the sensor.
The voltage value (analog signal) output from the sensor 26 is output as a digital signal to the signal processing unit 27 via an OP amplifier and an AD converter (not shown). Hereinafter, in this specification, a sensor output signal converted into a digital signal is abbreviated as “AD value (analog / digital conversion value)”. The AD value is data representing the output of the sensor 26 (that is, the measured value of the position of the hammer 2) by a numerical value in the range of “0 to 1023”, for example. In addition, if the independent sensors 26 (LED and photodiode) are provided for all the hammers (88) provided in the automatic performance piano, the cost becomes high. In this regard, the present applicant has proposed a technique for constructing a sensor matrix that can individually sense the movements of 88 hammers using 12 LEDs and 8 photodiodes. (See Kaihei 9-54584), the sensor 26 according to this embodiment is constituted by the sensor matrix. In addition, the arrangement | positioning structure of a sensor is not restricted to the structure by the said sensor matrix, The structure which arrange | positions the sensor 26 which consists of LED and a photodiode separately to all the hammers with which the said automatic performance piano is equipped may be sufficient. In the following description, only a hammer sensor that detects the position of the hammer is described as a sensor. However, a key or other appropriate movable member may be provided with a sensor that detects its movement.

  The signal processing unit 27 includes a CPU, a ROM, a RAM, a timer, and the like. The signal processing unit 27 calculates various information related to the performance performance of the automatic performance piano based on the output signal (AD value) supplied from the sensor 26, It is responsible for the execution and control of various signal processes such as performance information generation / recording process based on it. In FIG. 1, a calculation unit 28 shown in the signal processing unit 27 is a functional block representing a process for generating various information related to the performance performance of the automatic piano based on the movement of the hammer 2 expressed by the supplied AD value. More specifically, physical information such as speed information and acceleration information is obtained from the AD value (data representing the operation position of the hammer) output from the sensor 26, and the physical information (position, Based on the speed, acceleration, etc.), various kinds of information related to performance, such as a stringing timing, a stringing speed, and the like described in Patent Document 1, are performed. The processing unit 30 is a functional block representing processing for generating performance information according to the information generated by the calculation unit 28. The generated performance information may be output from the processing unit 30 and recorded on an appropriate recording medium or supplied to an external device (not shown) via an input / output interface (not shown). Alternatively, it may be configured to be supplied in real time to other devices on the network via a communication network (not shown). According to this embodiment, as will be described in detail later, the signal processing unit 27 determines the presence / absence of string striking using the AD value supplied from the continuous quantity sensor 26 and corrects the appropriate determination error. By performing the processing, it is possible to perform accurate string striking determination without being influenced by the change of the action mechanism over time.

  Here, with reference to FIG. 1, the reproduction | regeneration control system for performing the unmanned performance (automatic performance piano function) based on performance information in this automatic performance piano is demonstrated easily. The pre-reproduction processing unit 10 generates key trajectory data for reproducing each performance event included in the performance information based on performance information supplied from an appropriate recording medium (not shown), a real-time communication device, or the like. At the same time, a key original velocity instruction value (t, Vr) is generated using the trajectory data. The motion controller 11 generates and outputs a speed instruction value Vr corresponding to the position of the key 1 at time t based on the original speed instruction value (t, Vr). The servo controller 12 supplies an excitation current corresponding to the speed instruction value Vr to the solenoid 5, and compares the output speed Vy which is a feedback signal supplied from the solenoid 5 with the speed instruction value Vr. Servo control to match. In addition to the mechanical tone generation control by driving the solenoid 5 as described above, the pre-reproduction processing unit 10 also generates a sound source or a speaker based on performance data supplied from a recording medium, a real-time communication device, or the like. It also handles processing for supplying a control signal to the electronic musical tone generator 13 composed of the above. The electronic musical sound generator 13 generates musical sounds electronically based on the supplied control signal, and generates performance sounds according to performance information. It should be noted that any conventionally known data format, sound source method, etc. may be applied to the performance information when the electronic musical sound generator 13 performs electronic performance automatically.

The outline of the performance information recording / reproducing operation in the automatic performance piano having the above configuration will be briefly described. When the performer performs a piano performance, the signal processing unit 27 relates to the performance based on the detection result from the sensor 26. Various information is generated, and performance information representing the performance content of the piano performance by the performer is generated based on the generated various information. The performance information generated here may be created in an appropriate data format such as MIDI format. The created performance information is stored in an appropriate storage such as a hard disk, flexible disk or floppy (registered trademark) disk, compact disk (CD-ROM), magneto-optical disk (MO), ZIP disk, DVD (Digital Versatile Disk), semiconductor memory, etc. Can be recorded on a medium.
In the automatic performance piano, when the performance information is reproduced, the mechanical sound generation that causes the hammer 2 to strike the string by driving the key 1 by the electromagnetic solenoid 5 and the electronic musical sound generation unit 13 are used. Either electronic musical tone generation can be selected. In the case of mechanical musical sound generation, the electromagnetic solenoid 5 is driven and controlled by a drive signal (excitation current) according to the performance information to be reproduced, via the reproduction preprocessing unit 10, the motion controller 11 and the servo controller 12. By reproducing the key trajectory (stroke operation) according to the performance information, and controlling the stringing operation by the hammer 2, the piano performance according to the performance information is performed. In the case of electronic musical sound generation, the musical sound corresponding to the performance information supplied by the electronic musical sound generating unit 13 is electronically controlled by controlling the electronic musical sound generating unit 13 according to the musical performance information to be reproduced by the pre-reproduction processing unit 10. Generated.

  In the automatic performance piano according to this embodiment, the string was hit by the hammer from the physical quantity representing the movement of the hammer 2 detected by the continuous quantity sensor 26 when recording the performance performed by the performer. The following points are characteristic. That is, based on a preset reference value for string striking estimation and an AD value (that is, position information of the hammer 2) output from the sensor 26, it is estimated that the hammer 2 has reached a predetermined string striking position, In addition to generating string striking estimation information (labeling string striking / non-stringing), physical information (speed information and acceleration information) different from the position information representing the movement of the hammer 2 based on the AD value from the sensor 26. Generating / non-striking determination from the physical information of the hammer approaching the string before striking and the physical information of the hammer separating from the string after striking, and the estimation result and the determination If the results do not match, more accurate string determination can be performed by appropriately correcting the cause of the determination mismatch. Hereinafter, the processing in the signal processing unit 27 related to the string striking determination will be described in detail.

  First, when the power is turned on, the signal processing unit 27 performs a process of setting a “reference position parameter (reference value)” for associating the AD value supplied from the hammer sensor 26 with the actual operation position of the hammer 2. . That is, the hammer operation positions at a plurality of predetermined points are set in advance as reference positions, and AD value values (numerical values) representing the reference positions are stored as reference values. The signal processing unit 27 refers to each reference value to associate the AD value supplied in real time from the sensor 26 with each reference position, and determines the operation state of the hammer 2 according to the associated reference position. can do. In this embodiment, as the reference position, for example, the rest position of the hammer 2 (position of stroke amount 0 mm), the end position (stroke amount 48 mm from the rest position), the first reference position M1 (down 8 mm from the end position). 4 points) and a second reference position M2 (a position 0.5 mm lower than the end position) are set. The first reference position M1 and the second reference position M2 are defined as positions relative to the end position.

  FIG. 2 shows an example of processing for setting each reference value corresponding to the four reference positions in the automatic performance piano. In FIG. 2, when the automatic performance piano is turned on, the current position of the hammer 2 is sensed by the sensor 26, and the AD value output from the sensor 26 is taken into the signal processing unit 27 (step S1). ). Immediately after the power is turned on, it can be assumed that the key 1 is in a non-key-pressed state, that is, the hammer 2 is located at the rest position, so the AD value taken here corresponds to the rest position of the hammer 2. The reference value “rest value R” referred to as data is stored in the RAM. This AD value capturing process is performed for all the hammers, and the data of the respective rest values R is obtained for each hammer. Next, in step S2, a reference value “end value E” referred to as data corresponding to the end position of the hammer is used as a “calibration ratio” described below based on the rest value R acquired in step S1. And the calculated end value E is stored in the RAM. This is also performed for all the hammers, and “end value E” data is obtained for each hammer.

The “calibration ratio” represents the ratio of the AD value at the end position to the AD value at the rest position (see, for example, Japanese Patent Laid-Open No. 2000-155579). Here, the “calibration ratio” setting process will be briefly described. The calibration ratio setting process is a process executed at the time of factory shipment, for example. In response to an instruction from a controller (not shown), the calibration ratio setting process is started, the AD value of the hammer rest position and the AD value of the end position are measured, and the measured AD value of the rest position and the end position are measured. A calibration ratio is calculated based on the AD value. The calibration ratio setting process is performed individually for each of the 88 hammers. The calculated calibration ratio for each hammer is recorded in a nonvolatile memory such as a flash memory. By using this calibration ratio, it is possible to calculate the AD value at any other operation position such as the end position from the measured AD value and the calibration ratio only by actually measuring the AD value at the rest position of the hammer.
Although the specific numerical value itself of the AD value output from the sensor may fluctuate due to various factors such as aging and temperature change, the AD at the end position (or any point) with respect to the AD value corresponding to the rest position Since the ratio of the values can be regarded as constant, if the AD value that should correspond to the rest position can be specified using this calibration ratio, the specified AD value can be used regardless of the influence of aging, temperature change, etc. The AD value at the end position (or any point) according to can be estimated, that is, the rest of the four reference positions (rest position, end position, first reference position M1 and second reference position M2) Only the reference value (rest value R) corresponding to the position is measured by a sensor, and each reference value at other reference positions uses a calibration ratio based on the measured rest value R. There is an advantage that can be calculated Te.

  Now, referring back to FIG. 2, in step S3, using the calibration ratio, the rest value R stored in the RAM is referred to as AD values corresponding to the first reference position M1 and the second reference position M2 of each hammer. “First reference value m1” and “second reference value m2” are calculated and stored in the RAM. The first reference value m <b> 1 and the second reference value m <b> 2 are referred to when calculating the operation speed of the hammer to be described later, a string striking presence / absence determination process, and the like.

  Similarly, for the other movable members including the key 1, the reference position parameter can be set from the sensor output when the power is turned on (step S4).

FIG. 3 is a flowchart showing an example of a routine for obtaining the hammer speed executed in the signal processing unit 27. This is one of the main processes that can be placed on the automatic performance piano during normal operations such as recording performance information as performance information during a performance operation by a performer or during reproduction of performance information. The speed information of the hammer 2 to be obtained here includes various information relating to performance such as the calculation of the timing of striking and the calculation of the speed immediately before striking, including the determination of the presence or absence of the striking by the hammer 2. It is used as one of the basic elements when outputting. As shown in the figure, this routine loops the processes of steps S10 to S16 according to a predetermined activation cycle for each key.
In step S10, the signal processing unit 27 captures the AD value output from the sensor 26 for each activation opportunity of the routine, and stores the captured AD value in the RAM together with the time information TIME. Here, the signal processing unit 27 stores a data set composed of AD values and time information TIME acquired at the start opportunity (sampling time) for the past 20 times from a certain time, and from these 20 data sets, A data table TABLE1 as shown in FIG. 4 is created. In the table TABLE1, as shown in the figure, a set of AD values taken at the last 20 sampling points and a set of time information thereof are sequentially described. With this, the signal processing unit 27 shows temporal transition within a predetermined time. It is possible to grasp information on the continuous operation position of the corresponding hammer.

  In step S11, the presence / absence of a hammer operation (that is, key operation) is determined from the acquired AD value. The presence / absence determination of the hammer operation can be performed, for example, by determining whether or not the AD value taken in with reference to the rest value R has changed from the non-key-pressed state (rest position). If there is no hammer operation (key operation) (NO in step S11), the process returns to the top of the routine.

  In step S12, referring to the second reference value m2 stored in the RAM, whether or not the AD value fetched at the present time exceeds the second reference value m2, that is, the stroke position of the hammer 2 is the second. It is determined whether the reference position M2 has been displaced upward. The second reference position M2 is an arbitrary operation position (estimated stringing position) previously defined as a stringing position. When the hammer 2 exceeds the estimated stringing position, “the string is hit by the hammer 2”. Can be estimated. Performing string striking estimation based on the estimated string striking position and the AD value output from the sensor 26 is advantageous in terms of real-time performance with respect to actual hammer operation and quick operation determination. However, since the second reference value m2 used as the threshold value here is a value calculated from the actually measured rest value R and the calibration ratio at the time of power-on, there are various values such as the rest value R and the calibration ratio. As long as the correspondence between the parameter and the actual output value from the sensor 26 is accurate, its reliability is ensured. For this reason, if the input / output characteristics of the sensor 26 change due to changes in the action mechanism over time, the correspondence between the output value from the sensor 26 and the parameter may be shifted, and accurate estimation may not be performed. In this embodiment, in this embodiment, a hammer based on the AD value from the continuous amount sensor 26 and the estimated string-striking position (threshold value) is obtained by correcting the calibration ratio by a determination configuration as will be described in detail later. It will become clear from the latter stage that the string presence / absence estimation can be performed more accurately.

  In step S12, if the AD value captured at the present time exceeds the reference value m2 (threshold value), in step S13, the first stringing state st1 representing the operation state (whether stringing is present) of the hammer 2 is estimated. Set to state with string strike. If the current AD value does not reach the reference value m2, the first string-striking state st1 is set to a state where there is no estimated string-striking.

In step S14, the table TABLE1 is referred to, and it is checked whether or not the operation direction of the hammer 2 has been reversed from the sampling time points of 20 points at the sampling time point 5 points before the certain time point. The point in time when the operation of the hammer 2 is reversed can be specified by, for example, determining the displacement of the operation position of the hammer 2 from the state of increase / decrease in the AD value based on the table TABLE1. Here, as an example for convenience of explanation, the numerical value of the AD value when the hammer 2 is at the rest value is represented by the maximum value AD (MAX), and the AD value when the hammer 2 is at the end position is represented by the minimum value AD (MIN). Then, in one stroke displacement of the hammer 2 (that is, a displacement that reaches the end position from the rest position and then returns to the rest position), the AD value output from the sensor 26 is basically the maximum. It gradually decreases from the value AD (MAX), reaches the minimum value AD (MIN) at the apex (corresponding to the end position) of the hammer trajectory, and gradually increases from there. That is, it is considered that the point in time when the fluctuation of the AD value starts to increase from the decrease corresponds to the peak of hammer movement (striking point), and the operation direction of the hammer 2 is reversed at that point. Therefore, when the time point at which the AD value variation changes from decreasing to increasing is checked from the table TABLE1, the time point at which the operation of the hammer 2 is reversed can be specified.
The signal processing unit 27 examines the AD value fluctuation before and after the last five sampling points from the table TABLE1 from the table TABLE1 every time the routine is activated, and the AD value fluctuation changes from decreasing to increasing. Identify the time. Then, the point in time when the movement direction of the hammer 2 is reversed is regarded as a reference point corresponding to the peak of hammer movement (striking point), and a data set is extracted at five sampling points before and after the reference point. A data table TABLE2 as shown in FIG. Here, the reference time point corresponds to a sampling time point five previous points from a certain sampling time point (for example, the latest sampling time point) in the table TABLE1, and therefore the table TABLE2 is determined from the certain sampling time point. It consists of data sets at the last 11 sampling points.

  As shown in FIG. 5, the table TABLE2 includes data sets (“AD (−5), t (−5)” to “AD (5), t (5)”) at the 11 sampling points. In addition, speed information (“v (−4)” to “v (5)”) and acceleration information (“a (−4)” to “a (4)”) at each time point are described. That is, the reference time (AD (0), t (0)) corresponding to the movement peak (stringing point) of the hammer 2 and the respective data at the sampling time for five times before and after this reference time. Speed information and acceleration information are obtained for each set. The speed information at each time point is calculated based on the difference between data between any two points (for example, a data set at a certain sampling time point and a data set at the previous sampling time point) by linear approximation, for example. Can do. Further, acceleration information can be obtained by performing a differential operation on the calculated speed information. The specific method for calculating the speed information and the acceleration information is not limited to the above example, and any conventionally known method may be applied. Note that the speed information can be calculated relatively easily based on the difference in data between any two points. Therefore, prior to the creation of the table TABLE2, for example, when the table TABLE1 is created in step S10 described above, the speed information is calculated. You may keep it. If the speed information at each time point is calculated here, the speed information can be used to determine the reversal of the operation of the hammer 2 in step S14.

  If the operation direction of the hammer 2 is reversed in step S14 (yes in step S14), the process proceeds to step S15, and the process proceeds to a subroutine “string striking determination process” described next with reference to FIG. On the other hand, if there is no reversal of the operation direction of the hammer 2, step S14 is branched to no, and the routine of the hammer speed process is continued without entering the subroutine “string striking determination process”.

  A processing example of the “string striking determination process” will be described with reference to the flowchart shown in FIG. First, in step S20, with reference to the table TABLE2, it is determined whether or not the hammer 2 has hit a string. In the string striking determination here, speed information and acceleration information when the hammer 2 moves close to the string (before string striking), as viewed from the reference time points (AD (0), t (0)) in the table TABLE2, By comparing the speed information and the acceleration information when the hammer 2 moves away from the string (after stringing) with the conditions described in detail below, it is determined that the hammer 2 has actually hit the string.

  (1) Conditions for determining that a string has been struck reliably: velocity information v (0) at a reference time point (AD (0), t (0)) and a time point immediately before the reference time point (AD (−1), Speed information v (−1) at t (−1)) and speed information v (−2) at a time (AD (−2), t (−2)) that precedes the sampling time by two sampling times before the reference time ) To determine whether the speed information v (0), v (-1), and v (-2) has a predetermined speed (for example, 0.3 m / s) or more. The v (0), v (-1), and v (-2) are information representing the hammer speed immediately before the string is hit. As a result, the temporal transition of the movement state of the hammer 2 that is close to the string 4 is checked before stringing. If any of these has a predetermined speed (for example, 0.3 m / s) or more, the hammer 2 is It can be seen that he was exercising at a speed sufficient to strike the string. Therefore, if this condition is met, it can be reliably determined that the string is struck.

  (2) Conditions for determining that there is a high possibility that a string has been struck: absolute value a (0) of acceleration information at the reference time point (AD (0), t (0)), and three times before and after the reference time point The absolute value a (-3) to absolute value a (3) of each acceleration information at the sampling time ("AD (-3), t (-3)" to "AD (3), t (3)") By examining, the movement state of the hammer 2 approaching the string 4 immediately before striking and the movement state of the hammer 2 separating from the string 4 after striking are examined. Here, if the absolute value a (0) of the acceleration information at the reference time is the maximum among the absolute values a (−3) to the absolute value a (3) of each acceleration information, the hammer 2 is hit by the movement of the hammer 2. It can be determined that there is a high possibility that a string was performed.

  (3) Conditions for determining that the possibility of non-stringing is high: not meeting the determination condition of (2), that is, among absolute values a (−3) to absolute values a (3) of each acceleration information Has a value larger than the absolute value a (0) of acceleration information at the reference time point, and speed information at the reference time point obtained by a quadratic curve fitting method adapted to a quadratic curve obtained from a plurality of speed information items When v (0) is a value close to “0”, it can be determined that there is a high possibility that the string was not hit depending on the movement of the hammer 2.

  As described above, in the string striking determination performed with reference to the table TABLE2 in step S20, physical information (speed, acceleration) indicating the movement of the hammer 2 in the movement range of the hammer 2 including the string striking position (reference time). Based on the fluctuation state when the hammer 2 approaches the string 4 before stringing and the fluctuation state when the hammer 2 moves away from the string 4 after stringing, the hammering / non-stringing is collated. 2 makes it possible to determine with high accuracy that the string has actually been struck.

  In step S21, a second string-striking state st2 representing the operation state of the hammer 2 (string presence / absence) is set according to the determination result in step S20. The second string striking state st2 may simply represent the presence of string striking (when the condition (1) or (2) is satisfied) or no string striking (when the previous condition (3) is satisfied). . Of course, according to each of the above conditions (1) to (3), the three states of (1) surely stringing, (2) high possibility of stringing, and (3) high possibility of non-stringing are expressed. May be.

  In step S22, the first string-striking state st1 and the second string-striking state st2 are compared, and it is determined whether or not the states (both with or without string-striking) are the same. If yes (YES), the process proceeds to step S23 to enter a subroutine "correction process" described below. On the other hand, if the first state st1 and the second state st2 match (in the case of no), the process returns to the “hammer speed process” of FIG.

A processing example of the correction process will be described with reference to FIG.
First, in step S30, it is determined which of the following cases the mismatch of the two stringing states st1 and st2 corresponds to, and the reference value for stringing estimation is appropriately corrected (calibrated) according to each case.
(Case 1) When it is determined that there is no string striking in the string striking state st1, but it is determined that there is a string striking in the string striking state st2: Since the string-striking operation is performed, it is considered that the reference end value E set as the reference position parameter that is the basis of the string-striking state st1 is assumed to be higher than the actual end position. In this case 1, the process proceeds to step S31. In step S31, the AD value “AD (0)” at the time set as the reference time in the table TABLE2 is set as the new end value E. By calculating the ratio between the new end value E and the current rest value R, the calibration ratio of the hammer 2 is updated. When the calibration ratio is updated, various parameters (such as reference position parameters) are recalculated from the new calibration ratio.
(Case 2) When it is estimated that there is no stringing in the stringing state st2 while the stringing state st1 is estimated to be a stringed sound: Although it is estimated that the stringing state is in the stringing state st1, it is actually hitting Since the string operation is not performed, it is considered that the reference end value E set as the reference position parameter is assumed to be lower than the actual end position. In case 2, the process proceeds to step S32. In step S32, a value obtained by adding a predetermined numerical value to the AD value “AD (0)” at the time set as the reference time in the table TABLE2 is a new end. As a value E, the ratio between the new end value E and the current rest value R is obtained, and the calibration ratio of the hammer 2 is updated. When the calibration ratio is updated, various parameters such as a threshold value (reference value m2 of the second reference position M2) corresponding to the estimated stringing position are recalculated from the new calibration ratio. Then, the process exits the correction process routine and returns to the routine shown in FIG.

  In the correction process described above, the string is struck based on the new calibration ratio by correcting the calibration ratio to an appropriate value based on the AD value output from the sensor 26 in real time during the performance operation on the automatic piano. The threshold (second reference value M2) corresponding to the estimated position can be reset to a more appropriate value. Therefore, for example, even when the relative position of the action mechanism fluctuates due to changes over time and the calibration ratio changes, the calibration ratio can be corrected in real time, and the output value (position information) from the continuous quantity sensor 26 can be corrected. ) And the estimated string-striking position.

  Returning to FIG. 3, after performing the above-described string striking determination process and the correction process therein, in step S16, a first striking state set in the first string striking state st1 and “string striking determination process” to be described later is performed. Based on the string state st2, other processing such as generation of a note on / off (sound generation instruction) signal is performed. The note on / off signal is performance data including key number and velocity data (stringing speed), and may be configured in a data format such as MIDI format. According to the present invention, since the stringing determination configuration and the calibration ratio correction described above can perform stringing determination with higher reliability, the generation of a sound generation instruction signal and the like can be performed more accurately. It is possible to effectively prevent errors such as so-called “sound missing (no sound even though it should be pronounced)” or “sound (no sound despite non-sound)”.

  Next, another embodiment of the calibration ratio correction process will be described with reference to FIG. In step S40, it is determined whether or not the mismatch between the string-striking state st1 and the string-striking state st2 has continued three or more times. This is because, in step S22 of the string striking determination process of FIG. 6, the end value for calibration calculation is updated on condition that the mismatch between the string striking state st1 and the string striking state st2 continues three times. It will be. If the mismatch between the string-striking state st1 and the string-striking state st2 continues three or more times (yes in step S40), in step S41, the mismatch between the string-striking states st1 and st2 is the case 1 or case described above with reference to FIG. It is determined which case corresponds to 2. As a result, it is possible to prevent the malfunction from being corrected.

In case 1, the end value E is assumed to be higher than the actual end position. Accordingly, the following processing is performed: In step S42, the peak position of the movement locus of the hammer 2 is searched. For example, referring to the table TABLE2 in FIG. 5, the reference time points AD (0) and t (0) corresponding to the movement peak (stringing point) of the hammer 2 are set to the trajectory peak (deepest) position of the hammer 2. Can be output as the AD value. In step S43, the string striking speed is estimated from the actual operation of the hammer 2. For example, the striking speed is estimated by referring to the table TABLE2 in FIG. 5, extracting AD values of arbitrary plural points (for example, five points) from the operation measurement values of the hammer 2, and using the extracted AD values. Speed information can be calculated by a linear approximation method.
In step S44, referring to the “deflection amount output table”, the “deflection amount” x corresponding to the stringing speed is output. An example of the deflection amount output table is shown in FIG. The deflection amount output table is constituted by the correspondence relationship between the string striking speed and the pushing amount (string flexure amount of the string 4) when the hammer 2 driven at a certain string striking speed strikes the string 4. ing. The deflection amount output table is created using a predetermined experimental machine with a known end position, and the table created by the experimental machine is stored in each device (automatic piano). And By outputting the “bending amount” x corresponding to the string striking speed from the deflection amount output table shown in FIG. 9, the deflection amount of the string 4 by the string striking operation is acquired. That the string 4 bends (the hammer 2 pushes in the string 4) means that the hammer 2 has stroked beyond the contact position (end position) with the string 4 by the amount of deflection. In this case, the value obtained by correcting the AD value at the peak position obtained in step S42 with the “deflection amount x” obtained in step S44 can be regarded as a value corresponding to the end position. In step S45, a new end value E calculated based on the AD value of the peak position and the “deflection amount x” is output.

  In case 2, it is assumed that the end value E is lower than the actual end position: Therefore, in step S46, the peak position of the movement of the hammer 2 is searched. Referring to the data table TABLE2 in FIG. 5, the reference time points AD (0) and t (0) corresponding to the movement peak (striking point) of the hammer 2 are set as the trajectory peak (deepest) position of the hammer 2. It can be output as an AD value. In this case, since the end value E is assumed to be lower than the actual end position, a new end value E may be output immediately after the AD value of the peak position of the movement of the hammer 2 output here.

  In step S47, the current rest value R and the new end value E output by the above-described process are set as the rest value for calibration calculation and the end value for calibration calculation. In step S48, the calibration ratio is recalculated based on the newly set rest value and end value for calibration calculation.

  As described above, according to another example of the correction process shown in FIG. 8, the calibration ratio is updated based on the actual operation of the hammer 2, so that it is possible to flexibly cope with, for example, a change with time of the hammer 2. In addition, the calibration ratio can be updated in real time based on the actual operation of the hammer 2 during normal operation, such as during recording and playback of performances. Data can be generated.

  In the above embodiment, the processing example for correcting the calibration ratio in the correction processing has been described. However, the present invention is not limited to this, and processing is performed so as to correct the rest value R and end value E set as the reference position parameters. Also good. Further, the output value from the sensor may be modified. In the above embodiment, the example in which the speed information and the acceleration information are calculated based on the position information output from the continuous quantity sensor 26 has been described. However, the present invention is not limited to this, and the continuous quantity sensor 26 is configured as a speed sensor. Alternatively, position information and acceleration information may be calculated from the output speed information. Further, the position information, the speed information, and the acceleration information may be separately detected by independent sensors. When the position sensor, the speed sensor, and the acceleration sensor are configured by independent sensors, the dimensions of the sensors may be different from each other or may be common. Further, the information used as the determination element for the presence / absence of string striking in the string striking determination process shown in FIG. 6 is not limited to the speed information and acceleration information of the hammer 2 described above. Even such information can be used. For example, the vibration of the string 4 at the time of stringing may be detected by an appropriate sensor and the vibration information may be used. Alternatively, the vibration of the string 4 at the time of stringing may not be directly detected. The vibration sound generated by the vibration may be detected by an appropriate pickup.

In the embodiment described above, an example of detecting the operation of the key and the hammer has been shown. However, the present invention is not limited to such an embodiment, and the operation element and other members driven by the operation of the operation element The present invention can be applied to any form as long as it determines the abutting operation in relation to the driven member that abuts. For example, in a relationship between a damper pedal and a damper, the present invention may be applied to a form in which a contact operation of a damper against a string is continuously detected and determined.
In the above embodiment, an acoustic piano having an automatic performance function and a performance operation recording function has been described as the automatic performance piano. However, the acoustic piano may be either a grand piano or an upright piano. Moreover, this invention can be applied not only to an automatic performance piano but also to a mute piano . Further, the present invention is not limited to an acoustic piano, and can be applied to other various keyboard instruments such as an electronic piano.

The figure which shows the whole structure of the automatic performance piano which concerns on one Example of this invention. The flow which shows the process example performed at the time of power activation in the automatic performance piano which concerns on the same Example. The flow which shows an example of the routine which calculates | requires the hammer speed performed as main operation | movement in the automatic performance piano which concerns on the Example. The figure which shows an example of the data table TABLE1 showing the time transition of hammer operation | movement. The figure which shows an example of the data table TABLE2 showing the time transition of the exercise | movement state of the hammer produced based on the table TABLE1 of FIG. The flowchart which shows an example of the string striking determination process which concerns on the same Example. The flowchart which shows an example of the correction process which concerns on the same Example. The flowchart which shows another example of the correction process which concerns on the same Example. The figure which shows an example of the deflection amount output table which concerns on the Example.

Explanation of symbols

1 key, 2 hammer, 3 action mechanism, 4 strings, 5 electromagnetic solenoid, 6 damper, 7 back check, 10 playback pre-processing unit, 11 motion controller, 12 servo controller, 13 electronic musical sound generating unit, 26 sensor, 27 signal processing Part, 28 calculation part, 30 processing part

Claims (5)

An operator,
A driven member that is driven in accordance with the operation of the operating element and that abuts against other members in accordance with the driving;
Detecting means for detecting movement of the driven member;
Based on the detection output of the detection means and a predetermined reference value for estimation, an estimation means for estimating that the driven member is in contact with the other member and generating estimation information related to the contact;
Determination means for determining that the driven member has reached a contact position with another member;
A keyboard instrument comprising correction means for correcting the judgment of the estimation means according to the judgment result of the judgment means.   The correction means includes means for calibrating at least one of the output of the detection means and the reference value for estimation in the estimation means, and the correction of the judgment of the estimation means by the correction means includes the output of the detection means and the estimation The keyboard instrument according to claim 1, wherein the keyboard instrument is performed by calibrating at least one of estimation reference values in the means. The detection output of the detection means is first physical information indicating a first type of physical quantity indicating the movement of the driven member,
The determination unit determines contact of the driven member based on second physical information indicating a second type physical quantity indicating movement of the driven member in a movement range of the driven member including the contact position. The keyboard instrument according to claim 1 or 2, wherein: The detection means is a continuous quantity sensor that continuously detects position information of the driven member,
The first physical information is position information output from the sensor,
The second physical information is at least one of speed information and acceleration information of the operation of the driven member calculated based on position information output from the sensor,
The determination means determines whether or not the driven member is in contact with another member from a state corresponding to a temporal transition of at least one of the calculated speed information and acceleration information. The keyboard instrument according to any one of claims 1 to 3, wherein The reference value correcting means for correcting the estimation reference value when the estimation result of the estimation means and the determination result of the determination means differ by a predetermined number of times. The keyboard instrument described in crab.

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