Vibration presentation device, vibration generation system, vibration presentation program, recording medium storing vibration presentation program, and vibration generation method

Abstract

The present invention uses an actuator to present a low-frequency vibration that is not a resonance band of the actuator and is difficult to present, the low-frequency vibration being easily perceived (illustrated) by a person. A vibration presentation device (1) for presenting vibration in a first frequency band by means of an actuator (31) having a resonance frequency in a second frequency band that is larger than the first frequency band is provided with: an acquisition unit (101) for acquiring a signal including at least vibration in the first frequency band that is a resonance frequency lower than the second frequency band; a calculation unit (102) for determining a maximum value of the vibration of the first frequency band acquired by the acquisition unit (101), and determining a maximum value time, which is the time at which the vibration becomes the maximum value, from the maximum value; and a control unit (103) that, on the basis of the maximum time calculated by the calculation unit (102), controls the actuator within a transition time that is a time before and after the maximum time, and generates a single wave.

Description

Technical Field

[0001] The technology described in this specification relates to a vibration presentation device, a vibration generation system, a vibration presentation program, a recording medium storing the vibration presentation program, and a vibration generation method. Background Art

[0002] In recent years, in the fields of smartphones, game consoles, virtual reality (VR) devices, robot manipulation assistance, etc., in order to improve the somatosensory and telepresence, the upgrade of vibration feedback is being promoted (for example, refer to patent document 1). In vibration feedback, since the vibration perception sensitivity of human beings is the largest around 200Hz, the vibrators mounted on portable terminals such as smartphones are mostly equipped with small linear resonant actuator (LRA: Linear Resonant Actuator) type vibrators with a resonance frequency of about 200Hz in the frequency band of about 100 to 300Hz (for example, refer to patent document 2).

[0003] In recent years, LRAs have been becoming more broadband, and LRAs that can exhibit resonance frequencies of about 50 to 400 Hz have been developed. There are also devices and game console controllers that set the oscillator at a resonance frequency of 60 Hz to 100 Hz (for example, see Patent Document 3).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2003-228453

[0007] Patent Document 2: International Publication No. 2021 / 085506

[0008] Patent Document 3: Japanese Patent Application No. 2021-527257

[0009] Patent Document 4: Japanese Patent Application Publication No. 2004-181304 Summary of the invention

[0010] Problems to be solved by the invention

[0011] However, it is difficult for the LRA with a resonance frequency of about 50 Hz to 400 Hz to produce vibrations in a low-frequency region of several tens of Hz away from the resonance frequency. In order to make the resonance frequency below 50 Hz and further enhance the feeling of the low-frequency band, it is necessary to increase the mass of the resonance system or to mount another vibrator for this purpose, resulting in an increase in the volume occupied by the vibrator.

[0012] Patent document 4 discloses the following invention: for a movable body that moves between force-applying units such as springs, the amplitude of the movable body is adjusted by applying an accumulation signal and an attenuation signal to the coil control around the movable body, and the simulated vibration formed by the envelope connecting the vertices of the amplitude becomes a frequency that can be felt by a person, thereby suppressing the size of the movable body. However, this not only depends on the structure of the vibrator, but also the input of multiple signals is complicated. In addition, it is unclear whether even frequencies below 50 Hz can be reproduced.

[0013] Moreover, the movements that need to be reproduced by current game consoles, VR devices, etc. are complex, and require the simple provision of low frequencies, but this is very difficult with the technology disclosed in Patent Document 4, and cannot be used, especially when online real-time signal reproduction is required.

[0014] Therefore, there is a problem that it is difficult to express the physical sensation of low-frequency vibrations of several tens of Hz using a small information terminal such as a smartphone that is equipped with only an LRA having a resonance frequency of approximately 100 Hz to 300 Hz.

[0015] The purpose of the technology described in this specification is to present low-frequency vibrations that are difficult to present and are out of the resonance frequency band of the mounted actuator without using an additional actuator, and to present the low-frequency vibrations that are easily perceived (illusioned) by humans by studying the control of the actuator.

[0016] Solutions for solving problems

[0017] The vibration presentation device of the present invention is a vibration presentation device for presenting vibrations in the first frequency band by means of an actuator having a resonance frequency in a second frequency band greater than the first frequency band, and comprises: an acquisition unit for acquiring a signal including at least vibrations in the first frequency band having a resonance frequency lower than the second frequency band; a calculation unit for finding the maximum value of the vibrations in the first frequency band acquired by the acquisition unit, and finding the time when the maximum value is reached, i.e., the maximum value time, based on the maximum value; and a control unit for controlling the actuator to generate a single wave within a transition time including the time before and after the maximum value time based on the maximum value time calculated by the calculation unit.

[0018] Effects of the Invention

[0019] In the present invention, vibrations having a frequency lower than the resonance frequency band that can be expressed by the actuator can be converted into vibrations having a frequency that is easily perceived (perceived as) by humans and expressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural diagram schematically showing a structural example of a vibration generating system as an embodiment.

[0021] Figure 2It is explained by Figure 1 The graphs are of the principle of presentation processing of substitute vibrations for low-frequency vibrations performed by the vibration generating system shown, (a) is a graph showing an example of a presented low-frequency signal and a controlled single-shot waveform (short-time pulse waveform), and (b) is a graph showing an example of reverberant vibrations generated in a shell (based on measurement by a laser displacement meter).

[0022] Figure 3 It shows about Figure 1 The figures show the results of a subject experiment in which the vibration generating system shown was used to present a substitute vibration for a low-frequency vibration, wherein (a) is a table showing the options answered by the subjects, and (b) to (e) are graphs showing the answer results when the low-frequency waveform of the original (target signal) is 10 Hz, 20 Hz, 30 Hz, and 40 Hz, respectively.

[0023] exist Figure 4 In (a), it is explained Figure 1 The graph of the first example of the calculation process of the amplitude and timing of the vibration generating system shown in FIG. Figure 1 Graph showing a second example of the calculation process of the amplitude and timing of the vibration generating system shown.

[0024] Figure 5 is a graph illustrating the online calculation process of the amplitude and timing of low frequency vibrations.

[0025] Figure 6 Is used to illustrate the Figure 1 FIG. 1 is a block diagram of a process of generating a first vibration waveform and a second vibration waveform by the vibration generating system shown.

[0026] exist Figure 7 In the figure, (a) is a block diagram for explaining the vibration generation process when a vibrator based on an actuator is used, and (b) is a block diagram for explaining the vibration generation process when a portable terminal is used. DETAILED DESCRIPTION

[0027] The following describes the embodiments with reference to the accompanying drawings. However, the embodiments shown below are only examples and are not intended to exclude various modifications and technical applications not explicitly shown in the embodiments. That is, the embodiments can be implemented with various modifications within the scope of the gist thereof.

[0028] In addition, each figure is not intended to include only the components shown in the figure, and may include other components. In the following, in the figures, unless otherwise specified, the parts marked with the same reference numerals represent the same or similar parts.

[0029] [A] Implementation Method

[0030] A-1. System structure

[0031] Figure 1 1 is a diagram schematically showing a configuration example of a vibration generation system 100 according to an embodiment.

[0032] The vibration generating system 100 includes a vibration presentation device 1 and a vibration body sensing device 3 .

[0033] The vibration presentation device 1 includes a CPU 11 , a memory 12 , a storage device 13 , an input unit 41 , an output unit 42 , and a transmission unit 43 , which are connected via a bus 15 .

[0034] The vibration sensor device 3 includes an actuator 31 , a driving unit 32 , and a receiving unit 33 , and is housed in a housing 34 .

[0035] The vibration presentation device 1 and the vibration sensor device 3 may be separately provided or integrally provided. In addition, a part of the vibration presentation device 1 may also be provided in the vibration sensor device 3. In addition, when the vibration presentation device 1 and the vibration sensor device 3 are integrated, the housing 34 may also accommodate the entire vibration presentation device 1.

[0036] The vibration generating system 100 in one example of the present embodiment is mainly used for smartphones, game consoles, virtual reality (VR) equipment, robots, etc., but can also be applied to chairs, clothing, headphones, etc. including a vibration device.

[0037] The vibration presentation device 1 comprises: a central processing unit (CPU) 11 for controlling and driving; a memory 12 for storing programs, etc.; a storage device 13; an input unit 41 for acquiring information including original signals and other signals for the purpose of reproduction; an output unit 42 for outputting information other than tactile sensations such as vibrations to the user; a sending unit 43 for communicating information with the vibration sensor device 3; and a bus 15 for connecting them.

[0038] The CPU 11 is a processing device that performs various controls and calculations, and implements various functions by executing an operating system (OS) and a vibration display program stored in the memory 12. Figure 1 As shown, the CPU 11 can function as an acquisition unit 101 , a calculation unit 102 , and a control unit 103 .

[0039] CPU 11 is an example of a computer, for example, controls the overall action of the vibration presentation device 1. The device for controlling the overall action of the vibration presentation device 1 is not limited to CPU 11, for example, it can also be any one of MPU, DSP, ASIC, PLD, FPGA, and a special processor. In addition, the device for controlling the overall action of the vibration presentation device 1 can also be a combination of two or more of CPU, MPU, DSP, ASIC, PLD, FPGA, and a special processor. In addition, MPU is the abbreviation of microprocessor (MicroProcessing Unit), DSP is the abbreviation of digital signal processor (Digital Signal Processor), and ASIC is the abbreviation of application specific integrated circuit (Application Specific Integrated Circuit). In addition, PLD is the abbreviation of programmable logic device (Programmable Logic Device), and FPGA is the abbreviation of field programmable gate array (FieldProgrammable Gate Array).

[0040] The memory 12 is a recording medium that stores an operating system (OS) and a vibration presentation program, and is composed of a read-only memory (ROM) and a random access memory (RAM).

[0041] The storage device 13 is a device that can store data in a readable and writable manner, and for example, a hard disk drive (HDD), a solid state drive (SSD), or a storage class memory (SCM). The storage device 13 stores information acquired by the input unit 41, a signal related to the vibration to be reproduced, a tactile signal, and various data calculated by the calculation unit 102 through a vibration presentation program.

[0042] The input unit 41 is used to obtain various information online in the vibration presentation device 1, including sound information such as the sound of music, movies, games, etc., impact, feeling during operation, vibration generated when the robot contacts an object, etc. In addition, in the case where information that is desired to reproduce the tactile sensation is pre-stored in the storage device 13, etc., the input unit 41 may not be provided.

[0043] The output unit 42 generates images and sounds in the vibration presentation device 1 to present information other than the vibration sensor device 3 to the user. In addition, the output unit 42 may not be provided as long as images, sounds, etc. are not presented to the user. In addition, the output unit 42 may also be provided in the vibration sensor device 3.

[0044] The transmission unit 43 is a part that transmits the control signal via the reception unit 33 of the vibration sensor device 3 by wire or wirelessly.

[0045] When the vibration presentation device 1 and the vibration sensor 3 are integrated, the transmitter 43 may use a communication method such as SPI, I2C, I2S or an analog signal such as voltage. The transmitter 43 may be built into the CPU 11 as a function.

[0046] In the case of wired communication, a communication method such as USB, Thunderbolt (registered trademark), Ethernet (registered trademark), or HDMI (registered trademark) may be used.

[0047] In the case of wireless communication, for example, a communication unit for Bluetooth (registered trademark), WiFi, or ZigBee (registered trademark), or a communication unit for a wireless local area network (LAN: Local Area Network) may be used.

[0048] The acquisition unit 101 , the calculation unit 102 , and the control unit 103 of the CPU 11 will be described in detail.

[0049] The acquisition unit 101 is used to acquire signals such as sound information such as music, movie, game sound, etc., shock, feeling during operation, and vibration generated when the robot contacts an object obtained from the input unit 41.

[0050] In addition, when a signal or a tactile signal related to the vibration to be reproduced is stored in advance in the storage device 13 or the like, the signal is read out from the storage device 13 and acquired by the acquisition unit 101 .

[0051] The calculation unit 102 analyzes the tactile signal acquired by the acquisition unit 101 and separates and extracts it into the first frequency band and the second frequency band, or calculates the maximum value of the vibration of the first frequency band, the time (timing) of the maximum value, and the amplitude. The specific calculation process will be described later.

[0052] The control unit 103 is a part that generates a control signal to control the actuator, controls the actuator 31 to reproduce the second frequency band calculated by the calculation unit 102, and controls the actuator 31 to generate a pulse wave such as a sine wave or a rectangular wave having at least a specified period (hereinafter also referred to as "single wave period time") within a specified time including the maximum value in the first frequency band to reproduce the simulated first frequency band. In addition, as long as it is within the generated specified time, the period may be a waveform of half a period, 1.5 periods, or 2 periods, or a waveform of several periods with different amplitudes may be output. In addition, by using waveforms of several periods with different amplitudes, it is possible to effectively generate reverberation in the housing 34.

[0053] These generated sine waves and pulse waves can also be collectively referred to as single-shot waveforms. The single-shot wave cycle time for generating a single-shot waveform is a time less than one cycle of the reverberation vibration generated by the resonance system of the actuator 31 or the resonance system of the actuator 31 and the housing 34, and is, for example, a size that can be fully felt by the user. Considering the vibration frequency that the current actuator can generate, it is preferably a time of more than 0.002 seconds and less than 0.02 seconds. In addition, it can also be determined based on the ratio of the cycle of the waveform of the vibration acquired by the acquisition unit 101.

[0054] Next, the vibration sensor device 3 will be described.

[0055] The vibration sensor device 3 of this embodiment is a part that reproduces and provides the user with sound information such as sound of music, movies, games, etc., impact, feeling during operation, and tactile signals such as vibration generated when the robot contacts an object. The vibration sensor device 3 has an actuator 31 that generates vibration, a driving unit 32, and a receiving unit 33. In order to make the tactile signal reproduced by the actuator 31 closer to reality, the resonance system of the actuator 31 carried is in a frequency band of about 50 to 350 Hz as a high frequency band (second frequency band), and the human vibration perception sensitivity is high. In the present invention, for example, an actuator 31 of 200 Hz ± 150 Hz is used to reproduce the high frequency band, and the actuator 31 is used to convert the simulated vibration in the low frequency band (first frequency band) below 100 Hz (10 Hz to 100 Hz, especially 10 Hz to 50 Hz) into a frequency that can be felt by humans for presentation.

[0056] In the present embodiment, the actuator 31 is a voice coil type actuator using a magnet and a coil, such as an LRA (linear resonant actuator). The actuator 31 may also be disposed in the housing 34. In this case, the actuator 31 and the housing 34 form a resonance system. The resonance frequency of the resonance system of the actuator 31 may be, for example, 200 Hz ± 150 Hz. In addition, the upper limit value of the resonance system of the actuator 31 may be, for example, 350 Hz, and the lower limit value may be 50 Hz.

[0057] In addition, the actuator 31 is not limited to the voice coil type actuator, and the actuator 31 may be composed of a weight supported by an elastic body and connected to the housing 34. In this case, the resonance system is composed of the actuator 31, the elastic body, the weight, and the housing 34. The weight may also be a battery or various components in the housing 34.

[0058] The driving unit 32 drives the actuator based on a digital signal or an analog signal received by the receiving unit 33 and generated by the control unit 103 for controlling the actuator 31. The driving unit 32 may include an amplifier (not shown) for driving the actuator 31, a feedback circuit, and the like.

[0059] The receiving unit 33 is a part that receives a control signal transmitted from the transmitting unit 43 of the vibration presentation device 1. When the signal of the transmitting unit 43 is directly transmitted to the driving unit 32, the receiving unit 33 may be omitted.

[0060] A-2. Presentation Processing Alternative to Vibration

[0061] A specific method of reproducing the simulated first frequency band by replacing vibration according to the present invention is described below.

[0062] Figure 2 It is explained by Figure 1 FIG. 1 is a graph showing the principle of the presenting process of the substitute vibration for the low-frequency vibration by the vibration generating system 100 shown in FIG. Figure 2 (a) is a graph showing an example of a presented low-frequency signal and a controlled short-time single-shot waveform, Figure 2 (b) is a graph showing an example of reverberation vibration generated in the housing 34 (based on measurement by a laser displacement meter).

[0063] exist Figure 2 In the graph shown in (a), the horizontal axis represents time (Time[s]), the vertical axis represents amplitude (Amplitude), the dotted line graph represents the waveform of the original signal to be reproduced at 10 Hz (the target signal to be reproduced as an alternative vibration (hereinafter sometimes also referred to as the "target signal")) (Original signal), and the solid line graph represents the pulse signal (Control pulse signal) generated by the control actuator 31 as a single-shot waveform. In conjunction with the peak timing of the low-frequency signal of the continuous target signal, a short-time pulse signal is generated as an input waveform by the control actuator 31. Figure 2 In the example shown in (a), a sine wave of one cycle is used as the pulse signal input from the actuator 31. By generating the pulse signal in accordance with the peak of the low-frequency signal, a characteristic low-frequency cycle can be expressed.

[0064] The controlled pulse signal (in other words, the replacement waveform) is generated by the following equation: Here, A is the amplitude of the original low frequency, f is the frequency of the replacement stimulus, and t' is the time when the original low frequency has a maximum value.

[0065]

[0066] exist Figure 2In the graph shown in (b), the horizontal axis represents time (Time[s]), the vertical axis on the left represents the voltage of the original signal and the control signal (Original / Control signal[V]), and the vertical axis on the right represents the displacement based on the measured vibration (Measured vibration[μm]). In addition, the dotted line graph represents the original signal (target signal) (Originalsignal), the thick line graph represents the pulse signal (Control pulse signal) generated by controlling the actuator 31, and the thin line graph represents the displacement (Measured vibration) generated and measured in the housing 34 of the vibration generating system 100. For the short-term pulse input in the actuator 31, reverberation vibration is generated due to the inherent vibration of the housing 34 including the actuator 31. The reverberation vibration takes time to decay. It can be considered that the decaying waveform generates a low-frequency body sensation that is difficult to reproduce by the actuator 31.

[0067] A-3. Evaluation of the sensory sensation of alternative vibration

[0068] The extent to which the above-mentioned vibration-alternative presentation processing method can present low-frequency body sensations was actually investigated.

[0069] Figure 3 The figures show the results of the experiment on the subject of presenting the alternative vibration for the low-frequency vibration performed by the vibration generating system 100, (a) is a table showing the options answered by the subjects, (b) is a graph showing the results of the average value of the three answers of the subjects when the low-frequency waveform of the target signal is 10 Hz, (c) is a graph showing the results of the average value of the three answers of the subjects when the low-frequency waveform of the target signal is 20 Hz. (d) is a graph showing the results of the average value of the three answers of the subjects when the low-frequency waveform of the target signal is 30 Hz. (e) is a graph showing the results of the average value of the three answers of the subjects when the low-frequency waveform of the target signal is 40 Hz. (b) to (e) show the interquartile range and the median in addition to the maximum and minimum values ​​of the answer options.

[0070] exist Figure 3 In the experiment, sine waves of 10Hz, 20Hz, 30Hz, and 40Hz were set as low-frequency vibrations as target signals, and sine waves of 60Hz, 80Hz, and 100Hz were used as substitute vibrations for stimulation. The subjective sensation of the subjects was used to evaluate whether the presentation processing method using the above-mentioned substitute vibrations could present low-frequency vibrations as target signals. In the somatosensory experiment, the subjects felt the voice coil type vibrator that could present about 10Hz to 100Hz by holding it in one hand, so as not to make the subjects choose answers based on information other than the vibrations they felt. The subjects were 7 men and women in their 20s.

[0071] First, in order to teach the subjects the difference between low frequency and high frequency, a 10 Hz sine wave as a low frequency and an 80 Hz sine wave as a high frequency were repeatedly presented until the subjects could distinguish the difference.

[0072] As stimulation for the subjects to perform somatosensory evaluation, four types of low-frequency vibrations were performed with 10 Hz, 20 Hz, 30 Hz, and 40 Hz as the target signal: the low-frequency vibration itself (Raw Wave) as the target signal, an alternative vibration generated using a 60 Hz sine wave, an alternative vibration generated using an 80 Hz sine wave, and an alternative vibration generated using a 100 Hz sine wave.

[0073] In the somatosensory experiment, a voice coil vibrator was used to present the stimulus for 5 seconds, and the subjects were asked to Figure 3 The seven-level Likert scale shown in (a) answers whether the stimulus is judged to be low frequency or high frequency. In addition, the closer to scale 1, the higher the frequency (closer to the 80 Hz body sensation taught to the subjects), and the closer to scale 7, the lower the frequency (closer to the 10 Hz body sensation taught to the subjects).

[0074] The stimulus was presented repeatedly until the subject was able to answer. Each type of stimulus was presented randomly to avoid order effects. The subjects were tested with hearing blocked by white noise and soundproof earmuffs. The stimulus in the experiment was output from a voice coil vibrator (VP4, Acouve Laboratory, Inc.) held by the subject via a USB audio interface (ASUS, XONAR U7 MK II) and an audio amplifier (SMSL SA-36A PRO).

[0075] like Figure 3 As shown in (b), if the goal is to feel a low-frequency vibration of 10 Hz, the low-frequency vibration of 10 Hz itself (Raw Wave) is not to mention, and the single-shot waveforms of 60 Hz, 80 Hz, and 100 Hz can also present the same degree of very strong low-frequency sensation. In addition, in the case of 20 Hz, including the low-frequency vibration of 20 Hz itself (Raw Wave), it is possible to give a slightly lower low-frequency sensation than the case of 10 Hz.

[0076] Regarding 30 Hz and 40 Hz, there are many cases where a physical sensation close to high frequency is felt, including the low-frequency vibrations themselves (Raw Wave) of 30 Hz and 40 Hz.

[0077] On the other hand, at 10Hz, 20Hz, 30Hz, and 40Hz, it was observed that the median of the scale values ​​answered at each of the scales was close to the values ​​answered by the subjects in the low-frequency vibrations of 10Hz, 20Hz, 30Hz, and 40Hz, and the values ​​answered by the subjects in the alternative vibrations generated at 60Hz, 80Hz, and 100Hz. It can be considered that the subjects obtained a physical sensation similar to that of the low-frequency vibrations themselves (Raw Wave) of 10Hz, 20Hz, 30Hz, and 40Hz using the alternative vibrations generated at 60Hz, 80Hz, and 100Hz at each of the scales of 10Hz, 20Hz, 30Hz, and 40Hz.

[0078] As described above, it can be seen that if the method of presenting a processing alternative to vibration of the present invention is used, vibrations of 60 Hz, 80 Hz, and 100 Hz can also present a feeling close to the target low-frequency vibration to the subjects.

[0079] In addition, Figure 3 In the subject experiment, in order to strictly prevent the subjects from choosing answers based on information other than vibrations, a voice coil type vibrator capable of presenting vibrations of approximately 10 Hz to 100 Hz was used. However, by using the method of the present invention, a voice coil type vibrator that cannot present vibrations of 10 Hz to 50 Hz can also present to the subjects a feeling similar to low-frequency vibrations that cannot be presented originally.

[0080] A-4. Method for determining the amplitude and timing of alternative vibration based on target signal

[0081] The above describes a method for generating a substitute vibration based on an ideal original signal (target signal), but in reality, the original signal (target signal) to be reproduced in music, games, etc. is a complex vibration. The following describes how to generate the substitute vibration of the present invention in such a complex vibration.

[0082] Figure 4 (a) is used in Figure 1 An example of a signal of vibration or the like generated in music or the like, which is pre-acquired by the acquisition unit 101 of the vibration generating system 100 shown in the figure, or pre-stored in the storage device 13 or the like, and a graph illustrating a first example of calculation processing of the timing of generating a single-shot waveform by the calculation unit 102 using the amplitude and the control unit 103 to control the actuator 31, Figure 4 (b) is a graph illustrating the second example.

[0083] exist Figure 4In the first example shown in (a), the vibration to be reproduced is represented as a low-frequency signal (original signal (target signal)) after being separated into a high-frequency signal and a low-frequency signal as described later. The low-frequency signal is a signal below a specified frequency, for example, below 100 Hz, preferably below 80 Hz, and more preferably below 60 Hz. It can also be appropriately determined according to the area of ​​the actuator 31 that is difficult to reproduce. In addition, the low-frequency signal can be processed as a whole signal of the separated low-frequency signal, or it can be further separated into specified different low-frequency areas (for example, in the case of obtaining a low-frequency signal of 10 Hz or more below 80 Hz, it can also be further separated into 10 Hz to 50 Hz and 50 Hz to 80 Hz, and the processing of the calculation unit 102 is applied as each low-frequency signal). In this case, various driving parameters of the actuator 31 such as the waveform of the single wave, the cycle time of the single wave, and the amplitude can also be controlled for each separated frequency band, so as to combine multiple alternative vibrations that are closer to human body sensation for each frequency band for presentation.

[0084] The calculation unit 102 calculates a plurality of maxima and minima contained in the signal waveform of the low-frequency band. It can be seen from the experimental results of the inventor that when a substitute vibration is generated at a very short time interval in which the reverberation vibration is not fully attenuated, the subject will not feel the low-frequency vibration as the target, but will perceive it as the original high-frequency vibration of the actuator 31. Therefore, in order to generate a substitute vibration for the low-frequency vibration, adjacent maxima among the calculated multiple maxima are selected to be separated in time by a prescribed interval (hereinafter, sometimes also referred to as "interval time") (for example, 0.1 seconds or more). In the case where adjacent maxima are not separated in time by more than the prescribed interval time, only the most characteristic (larger) maxima among the adjacent maxima are selected. In the example shown in the figure, the point marked with "X" is not separated by more than the prescribed interval time, so it is not selected as a maxima. The position of the maxima selected in this way (hereinafter also referred to as "maximum time") is calculated as the timing time for presenting the substitute vibration.

[0085] On the other hand, regarding the amplitude, in the first example, the distance between the intersection points of perpendicular lines drawn from the local value to the straight line connecting the plurality of local values ​​is calculated as the amplitude of the substitute vibration (see the double arrow) (hereinafter sometimes also referred to as "local value amplitude").

[0086] As described above, the timing and amplitude for presenting the alternative vibration are determined.

[0087] exist Figure 4 In the second example shown in (b), the calculation unit 102 calculates only a plurality of local maximums included in the waveform of the low frequency band. The selection of local maximums is the same as in the first example, and the position of the selected local maximum (local maximum time) is calculated as the timing time for presenting the alternative vibration.

[0088] On the other hand, in the second example, regarding the local maximum amplitude, the distance from a predetermined reference value to the local maximum is calculated as the amplitude of the substitute vibration (see the double-headed arrow).

[0089] The first example is effective when the background noise is large and the target low-frequency signal waveform is small compared to the noise. On the other hand, the second example is effective when the target low-frequency signal waveform is sufficiently large compared to the noise.

[0090] The timing of outputting a single-shot waveform does not necessarily need to be strictly the maximum time, and can also include the time before and after the maximum time, that is, it can be generated by migrating from the maximum time (hereinafter also referred to as "migration time"). The prescribed time migration (migration time) can be set to the time when the shell vibration (reverberation vibration) controlled by the single-shot waveform is the largest and coincides with the maximum time obtained from the target signal or is approximately the same as the maximum time, to the extent that people do not feel uncomfortable.

[0091] The transition time is determined by the degree of deviation that a person can tolerate from the visual and auditory senses presented by the output unit 42. In existing studies, there is a threshold value that a person can notice a deviation of about 0.04 seconds in repeated body sensations and about 0.03 seconds in single body sensations. Therefore, the transition time can be set to be within a range of about ±0.04 seconds, but in order not to make sensitive people feel uncomfortable, it is preferably set to be within a range of about ±0.02 seconds.

[0092] Furthermore, it is preferable that the generation timing of the single-shot waveform maintains the calculated interval time of the maximum value.

[0093] The timing does not need to be strictly the maximum time because: even if the timing of outputting a single-shot waveform deviates by a certain amount, the person who feels the vibration will hardly notice it. It can be considered that for presenting alternative vibrations in the low-frequency area to the user, it is important to reproduce the time between the main maxima in the target signal to be reproduced.

[0094] In addition, Figure 4 In (a) and (b), the maximum value and the maximum value time are determined based on the waveform, amplitude height, etc., but are not limited to this. For example, they can also be obtained based on the square average value, effective value, change amount, etc. of the signal. As long as the maximum value and the maximum value time that are characteristic points of the signal can be determined, any method is acceptable.

[0095] The amplitude of the alternative vibration does not need to be Figure 4The exact size of the maximum amplitude obtained in (a) and (b) can be determined by multiplying the obtained maximum amplitude by a specified ratio. The specified ratio can also be adjusted according to the characteristics of the shell and actuator used in a manner close to the low-frequency body sensation of the original signal (target signal). The calculated amplitude can also be adjusted by an exponential function, etc. to match the subjective intensity of nonlinearity perceived by humans. The specified ratio can be, for example, greater than 80% and less than 120% relative to the obtained maximum amplitude.

[0096] Furthermore, when the maximum amplitude of the reproduced signal does not vary that much, the amplitude of the substitute vibration may be presented as a pre-existing constant amplitude. In this case, it is not necessary to find the maximum amplitude.

[0097] Next, a method for determining the amplitude and timing of the low-frequency vibration of the target signal acquired by the input unit 41 on-line and in real time will be described.

[0098] Figure 5 It is a curve chart illustrating the processing of determining the amplitude and timing of the vibration after the information acquired online and in real time by the input unit 41 is acquired as a signal by the acquisition unit 101, separated into high-frequency vibration and low-frequency vibration, and the low-frequency vibration as the target is extracted, and the horizontal axis is the passage of time.

[0099] The extracted original low-frequency vibration signal (target signal) is divided into certain time intervals, and the maximum value in each divided interval is calculated. The certain divided interval can be consistent with the interval required for the processing of the separated high-frequency vibration. The divided interval only needs to be less than 0.02 seconds, and can also be an interval of 0.01 seconds, 0.005 seconds, etc. In the divided interval, the interval where the maximum value changes from increasing to decreasing is detected, and the maximum value before the change to decrease is calculated as the maximum value time of the original signal. When calculating the maximum value, time differentiation can be used. After the maximum value (peak value) is detected, during the specified time T (for example, within 0.1 seconds) determined according to the above-mentioned interval time, the next peak value can be excluded according to the specified rules (for example, not more than 20% greater than the previous maximum value, etc.). Figure 5 The 0 mark in the figure indicates an interval with a maximum value that was detected within a specified time and was not excluded, and the × mark indicates an interval with a maximum value that was excluded.

[0100] Case #1 shows a case where the next maximum value is not detected within the prescribed time T. In this case #1, the detected maximum value is determined as the output timing (maximum time) of the single wave as usual. Case #2 shows a case where the next maximum value is detected within the prescribed time, but it is not excluded because the next maximum value is larger than the previous maximum value by a value larger than the prescribed value. The prescribed value is, for example, set to be 20% or more larger than the previous maximum value. In this case #2, both the first detected maximum value and the next maximum value that is 20% or more larger than the previous maximum value are determined as the output timing (maximum time) of the single wave. However, the passage of the prescribed time T may be given priority, and the next maximum value that has not passed the prescribed time T may be excluded from the output timing of the single wave. Case #3 shows a case where the next maximum value is detected within the prescribed time T, but it is excluded because it is smaller than the previous maximum value. In this case #3, only the first detected maximum value is determined as the output timing, and the next smaller maximum value is excluded from the output timing of the single wave. However, the elapsed time of the specified time T may be prioritized, and when the next maximum value that has not passed the specified time T in case #2 (the initial maximum value as the output timing in case #3) is excluded from the output timing of the single wave, the next small maximum value in case #3 may be used as the output timing of the single wave (maximum time).

[0101] Whether to give priority to a value greater than the previous local maximum value and greater than a predetermined value or to give priority to the elapsed time of the predetermined time T is determined according to the conditions of the reproduced signal and the conditions of presentation.

[0102] The method of calculating the maximum value can also be used to calculate the minimum value in the interval and the interval from decreasing to increasing. Figure 4 The method (a) of can calculate the amplitude of a single-shot waveform in a short time. In the case of online processing, the output timing of the single-shot wave is Figure 4 After calculating the amplitude of the single-shot waveform by the methods shown in (a) and (b), the single-shot waveform is output as quickly as possible. Regarding the amplitude, the signal may be buffered for a predetermined time T or longer to calculate the amplitude of the single-shot waveform in advance.

[0103] When reproducing online, you can Figure 4 The methods (a) and (b) of the present invention reset the output timing and amplitude of the original signal obtained online as the signal obtained in advance. On the other hand, in order to reproduce the feeling when online, the output timing and amplitude when online can also be pre-stored in the storage device 13, and reproduced with the output timing and amplitude.

[0104] exist Figure 4 (a), (b), Figure 5In the embodiment, the maximum value time and the maximum value amplitude calculated by the calculation unit 102 are stored in the storage device 13 as time series data for reproduction in association with other visual and auditory information. By reading the time series data for reproduction stored in the storage device 13, the control unit 103 can control the driving timing of the actuator 31 at any time together with the visual and auditory information, thereby providing the user with a sense of presence.

[0105] A-5. Processing of the calculation unit

[0106] Next, the processing of the calculation unit 102 of the vibration generation system 100 will be described in detail.

[0107] Figure 6 It is a block diagram for illustrating the generation process of a vibration waveform of a first frequency band as a low-frequency region and a vibration waveform of a second frequency band as a high-frequency region performed by the calculation unit 102 based on original signals such as vibrations generated in music, movies, games, etc. acquired by the acquisition unit 101, or original signals pre-stored in the storage device 13, etc.

[0108] Step 201 is a step of separating the signal below a specified frequency into a high-frequency band signal H(t) and a low-frequency band signal L(t) from the signal X(t) acquired by the acquisition unit 101 or pre-stored in the storage device 13, etc. (in other words, the signal as the reproduction target before conversion).

[0109] The high-frequency band signal H(t) is filtered by a high-frequency bandpass filter such as a high-pass filter to remove signals below a predetermined frequency. The separation and removal means are known methods. In the second vibration waveform generation step 202, the separated high-frequency band signal H(t) is used to generate the second vibration waveform S2(t) as a waveform of the high-frequency band.

[0110] On the other hand, the low-band signal L(t) below the specified frequency is filtered out from the signal X(t) using a low-band filter such as a low-pass filter. Next, in the calculation step 203 of the calculation unit 102, based on the extracted low-band signal L(t), the Figure 4 , Figure 5 The amplitude (maximum amplitude) Ai (i represents the number of the generated single wave) and the output time (maximum time) ti of the single wave are calculated by the method described in step 203. The first vibration generating step 204 generates a first vibration waveform (substitute vibration) S1 (t) as a low-frequency band waveform based on the amplitude Ai and the output time ti of the single wave calculated in step 203. At this time, the first vibration generating step 204 determines the shape of the single wave by referring to the single wave parameters used to determine the single wave waveform. The single wave parameters may include numerical values ​​such as the single wave cycle time, transition time, interval time, or amplitude ratio of the single wave.

[0111] A-6. Processing of the control unit

[0112] Figure 7 (a) is a block diagram for explaining a vibration generation process when the actuator 31 is controlled by the control unit 103 of a general device. Figure 7 (b) is a block diagram for explaining the vibration generation process when using a device such as a portable terminal such as a smartphone that has a device-specific parameter conversion function.

[0113] Figure 7 The high frequency gain adjustment step 302 of (a) uses a high frequency band gain adjuster to adjust the high frequency band gain of Figure 6 The high frequency gain of the second vibration waveform S2(t) of the high frequency band signal generated in the second vibration waveform generating step 202 is adjusted. On the other hand, in the low frequency gain adjusting step 303, a low frequency band gain adjuster is used to adjust the high frequency gain of the second vibration waveform S2(t) of the high frequency band signal generated in the second vibration waveform generating step 202. Figure 6 The first vibration waveform (substitute vibration) S1 ( t ) of the low-frequency band signal generated in the first vibration generating step 204 is subjected to low-frequency gain adjustment.

[0114] In the synthesis step 304 , the gain-adjusted first vibration waveform S1 ( t ) and the second vibration waveform S2 ( t ) are synthesized into a synthesized wave. In the driving step 305 , based on the synthesized wave of the synthesis step 304 , the control unit 103 of the vibration generating system 100 generates a signal to drive the actuator 31 .

[0115] exist Figure 7 In (b), when the vibration generating system 100 has a parameter conversion function unique to a device such as a portable terminal, in the high-frequency conversion step 402, for the high-frequency band signal, a conversion based on a conversion defined by an operating system (OS) of the portable terminal is performed. Figure 6 The second vibration waveform S2(t) of the high-frequency band signal generated in the second vibration waveform generation step 202 is converted into a high-frequency parameter sequence. In step 403, the signal converted into a high-frequency parameter sequence in step 402 is converted into a time series and an amplitude series. Then, in step 404, the control unit 103 drives the actuator 31 to create and reproduce the tactile pattern.

[0116] On the other hand, for the low frequency band signal, in step 502, Figure 6 The amplitude Ai and output time (timing) ti of the single wave calculated by the calculation unit 102 in the calculation step 203 are converted into parameters unique to the portable terminal. In step 503, the signal converted into a parameter sequence is converted into a time series and an amplitude series. Then, in step 504, the control unit 103 drives the actuator 31 to create and reproduce the tactile pattern.

[0117] [B] Modification

[0118] In the vibration presentation device 1 in the above-described embodiment, vibrations in a low-frequency band of about several tens of Hz, which is lower than the resonance frequency band that can be presented by the actuator, are converted into vibrations that are easily felt by humans.

[0119] The present invention is performed using an LRA having a resonance frequency of about 100 Hz to 300 Hz, which is generally mounted on a portable terminal or the like, and can be used in combination with various techniques.

[0120] For example, the inventor of the present application disclosed the following technology in the cited patent document 2: by using an energy control unit to maintain the energy of a signal at a high frequency, the signal is converted to about 200 Hz while maintaining the tactile sensation of the high frequency. This technology can be used together with the method of presenting low-frequency band vibration based on alternative vibration of the present application. By combining the present invention and the technology disclosed in patent document 2, even if a narrow-band LRA is used, a wide-band physical sensation of about several tens of Hz to 400 Hz can be presented, which can increase the design freedom of the device and achieve miniaturization and low cost.

[0121] [C] Effect

[0122] According to the vibration presentation device, the vibration presentation program, the computer-readable recording medium having the vibration presentation program recorded thereon, and the vibration presentation method in the embodiments, for example, the following effects can be achieved.

[0123] The present invention converts vibrations with frequencies lower than the resonance frequency band of the actuator 31 into vibrations that are easily perceived by humans as low frequencies by generating alternative vibrations through the actuator 31. In particular, in portable devices such as smartphones that use LRA as a vibrator, it has been difficult to express low frequencies of about 10 Hz to 50 Hz in LRA in the past, but by using the present invention, low-frequency body sensations can be expressed.

[0124] As a result, low-frequency vibrations can be expressed in portable devices, game controllers, etc., achieving vibration expression with a sense of presence. In addition, the body-sensing vibrations of music, movies, videos, etc. in portable devices, etc. can be presented.

[0125] The present invention obtains a signal of vibration of the first frequency band as a low-frequency band from an original signal as a reproduction target, obtains the maximum value of the vibration of the first frequency band obtained by the calculation unit 102, and obtains the time when the maximum value is reached, i.e., the maximum time, and based on the calculated maximum time, drives the actuator 31 to generate a single wave within a migration time around the maximum time that does not affect the human body sensation. Thus, by presenting simulated low-frequency vibrations, even if the actuator 31 cannot generate low-frequency band vibrations, the user's low-frequency body sensation can be presented, and no additional actuator is required, thereby achieving miniaturization of the device.

[0126] Furthermore, by finding the maximum amplitude at the maximum time, it is possible to present low-frequency vibration with higher accuracy.

[0127] In addition, by determining the single-shot wave cycle time and transition time for generating a single-shot wave based on human body sensation, etc., it is possible to reduce the vibration feeling of high frequencies.

[0128] When calculating the maximum value time from a signal having multiple maximum values, the calculation unit 102 sets the time interval between adjacent maximum values, ie, the interval time, to be greater than 0.1 seconds, so that the presented alternative waveform does not give a high-frequency vibration feeling to the human body.

[0129] When vibration is provided online, the calculation unit 102 may calculate the second maximum value even if the interval between the first and second maximum values ​​is less than the specified interval time when the intensity of the second maximum value following the first maximum value among the multiple maximum values ​​is greater than the intensity of the first maximum value by a specified ratio. Thus, in real-time situations such as online, by providing a substitute waveform to the user at a characteristic point in the original waveform, low-frequency body sensation can be reflected in real time.

[0130] The control unit 103 generates a sine wave or a pulse wave with an intensity of 80% or more and 120% or less relative to the intensity of the local amplitude. This makes it possible to appropriately control the intensity of the alternative waveform and further improve the sense of presence.

[0131] The actuator of the present invention uses a housing that generates reverberant vibrations, and by utilizing the reverberation, it is possible to present a more realistic low-frequency substitute vibration to the user.

[0132] [D] Other

[0133] The disclosed technology is not limited to the above-mentioned embodiments, and can be implemented with various modifications within the scope of the gist of the embodiments. The structures and processes of the embodiments can be selected or discarded as needed, or can be combined appropriately.

[0134] exist Figure 1 The vibration generating system 100 shown in the figure includes one actuator 31 , but the present invention is not limited thereto. The number of actuators 31 included in the vibration generating system 100 can be changed in various ways.

[0135] Description of Reference Numerals

[0136] 1: vibration presentation device; 3: vibration body sensing device; 11: CPU; 12: memory; 13: storage device; 15: bus; 31: actuator; 32: driving unit; 33: receiving unit; 34: shell; 41: input unit; 42: output unit; 43: sending unit; 100: vibration generating system; 101: acquisition unit; 102: calculation unit; 103: control unit.

Claims

1. A vibration presentation device for presenting vibrations in the first frequency band by means of an actuator having a resonance frequency in a second frequency band greater than the first frequency band, the vibration presentation device comprising: an acquisition unit configured to acquire a signal including at least vibration in the first frequency band which is a resonance frequency lower than the second frequency band; a calculation unit configured to obtain a local maximum value of the vibration in the first frequency band obtained by the acquisition unit, and obtain a local maximum time, which is a time when the local maximum value is reached, based on the local maximum value; and A control unit controls the actuator to generate a single wave within a transition time including a time before and after the maximum value time based on the maximum value time calculated by the calculation unit.

2. The vibration presentation device according to claim 1, wherein: The calculation unit obtains a local maximum amplitude which is an amplitude of a local maximum value within the local maximum time.

3. The vibration presentation device according to claim 1, wherein: The single-shot wave cycle time for generating the single-shot wave is a time of 0.002 seconds or more and 0.02 seconds or less.

4. The vibration presentation device according to claim 1, wherein: The migration time is less than 0.04 seconds.

5. The vibration presentation device according to claim 1, wherein: The calculation unit calculates a plurality of the local maximum values, and calculates the local maximum time for a time interval between adjacent local maximum values ​​that is equal to or greater than 0.1 seconds.

6. The vibration presentation device according to claim 5, wherein: The calculation unit calculates a plurality of the maximum values, and when the intensity of a second maximum value immediately following a first maximum value among the plurality of maximum values ​​is greater than the intensity of the first maximum value by a specified proportion, the maximum value time is calculated even if the interval time between the first maximum value and the second maximum value is less than the interval time.

7. The vibration presentation device according to claim 2, wherein: The control unit generates the single wave having an amplitude of 80% or more and 120% or less with respect to the local maximum amplitude.

8. The vibration presentation device according to claim 1, wherein: The first frequency band is greater than or equal to 10 Hz and less than or equal to 100 Hz.

9. The vibration presentation device according to claim 1, wherein: The calculation unit calculates the maximum value of the vibration based on the waveform of the vibration or the amplitude of the vibration.

10. A vibration generating system comprising: The vibration presentation device according to claim 1; the actuator having a resonant frequency in the second frequency band; and A vibration sensor device includes a housing that generates reverberant vibrations through control of the actuator.

11. The vibration generating system according to claim 9, wherein: The transition time is set to a time when the reverberation vibration of the housing is maximum within a time period including the maximum value time.

12. A vibration presentation program, configured to cause a computer to execute: a step of acquiring a signal including vibration of a first frequency band which is a resonance frequency lower than a second frequency band; a calculation step of obtaining a maximum value of the vibration in the first frequency band obtained in the obtaining step, and obtaining a time when the maximum value is reached, that is, a maximum value time, based on the maximum value; and A driving step of generating a single wave by controlling the actuator having a resonance frequency in a second frequency band within a transition time including a time before and after the maximum value time based on the maximum value time calculated in the calculating step. 13 . A recording medium storing the vibration presentation program according to claim 12 .

14. A vibration presentation method for presenting vibrations in the first frequency band by means of an actuator having a resonance frequency in a second frequency band greater than the first frequency band, the vibration generation method comprising: a step of acquiring a signal including at least vibration of the first frequency band which is a resonance frequency lower than the second frequency band; a calculation step of obtaining a maximum value of the vibration in the first frequency band obtained in the obtaining step, and obtaining a time when the maximum value is reached, that is, a maximum value time, based on the maximum value; and A driving step of generating a single wave by controlling the actuator having a resonance frequency in the second frequency band within a transition time including a time before and after the maximum value time based on the maximum value time calculated in the calculating step.

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