Stimulation adjustment device, stimulation adjustment method, and stimulation adjustment program

Abstract

Provided are a stimulus adjustment device, a stimulus adjustment method, and a stimulus adjustment program that make it possible to automatically adjust the intensity of stimuli presented to a user. The stimulus adjustment device of an embodiment is provided with: a signal input part for inputting a measurement signal of electrodermal activity of a user; an analysis part for analyzing the electrodermal activity on the basis of the measurement signal; an adjustment part for generating an instruction signal for adjusting the intensity of stimuli presented to the user according to the results of the analysis of the electrodermal activity; and a signal output part for outputting the instruction signal.

Description

[Technical field]

[0001] An embodiment of the present invention relates to a stimulation adjustment device, a stimulation adjustment method, and a stimulation adjustment program. [Background technology]

[0002] There are known systems that present tactile stimuli to humans for various purposes, such as treatment, training, beauty, entertainment, etc. In such systems, it is necessary to calibrate the tactile stimulation in advance so that the intensity of the stimulation is appropriate for the purpose.

[0003] For example, when using electrical muscle stimulation (EMS) technology to present electrical stimulation to muscles to induce involuntary contraction, the stimulation intensity must be adjusted to a range in which the user does not feel pain. A method for calibrating the stimulation intensity in advance has been proposed for a system that uses EMS to control the movement of a user's hands to assist in learning to play a musical instrument (see, for example, Non-Patent Document 1). [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Emi Tamaki, Takashi Miyaki, and Jun Rekimoto, "PossessedHand: Techniques for Controlling Human Hands using Electrical Muscles stimuli.", Proceedings of the SIGCHI Conference on Human Factors in Computing Systems. 2011 [Non-Patent Document 2] Ebrahim Babaei et al. "A Critique of Electrodermal Activity Practices at CHI.", Proceedings of the 2021 CHI Conference on Human Factors in Computing Systems. May 8-13, 2021. Summary of the Invention [Problem to be solved by the invention]

[0005] In conventional technology, the intensity of tactile stimulation is usually adjusted by the user's own direct operation. However, when adjusting based on the user's self-reporting, there is a risk that the user may falsely increase the stimulation intensity even though he or she is actually feeling pain, and use the system in a painful state.

[0006] Even if you didn't feel any pain during the pre-calibration, you may start to feel pain after a long period of use due to sweating on your skin, which makes it more conductive to electricity, or due to accumulated muscle fatigue. In such cases, if you have to recalibrate yourself, it will be a hassle.

[0007] This invention has been made in light of the above-mentioned circumstances, and its object is to provide a stimulation adjustment device, a stimulation adjustment method, and a stimulation adjustment program that enable automatic adjustment of the intensity of stimulation presented to a user. [Means for solving the problem]

[0008] In one embodiment of the present invention, a stimulation adjustment device is provided, comprising a signal input unit to which a measurement signal of a user's electrodermal activity is input, an analysis unit to analyze the electrodermal activity based on the measurement signal, an adjustment unit to generate an instruction signal to adjust the intensity of the stimulation presented to the user based on the results of the analysis of the electrodermal activity, and a signal output unit to output the instruction signal. Effect of the Invention

[0009] A stimulation adjustment device according to an embodiment of the present invention outputs an instruction signal for adjusting the intensity of stimulation presented to a user based on an analysis result of the user's electrodermal activity. It is known that when the user feels pain, for example, and psychological sweating occurs, the value of the user's electrodermal activity (EDA) changes (see Non-Patent Document 2). Therefore, by analyzing the user's electrodermal activity, it is possible to estimate the degree of psychological sweating, and therefore the degree of the user's pain. Therefore, a stimulation adjustment device according to an embodiment of the present invention can output an instruction signal for automatically adjusting the intensity of stimulation in consideration of the degree of the user's pain, without requiring a direct operation by the user.

[0010] That is, according to the present invention, it is possible to provide a stimulation adjustment device, a stimulation adjustment method, and a stimulation adjustment program that enable automatic adjustment of the intensity of a stimulation presented to a user. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a block diagram showing an example of the overall configuration of a system including a stimulation adjustment device according to an embodiment. [Diagram 2] FIG. 2 is a block diagram illustrating an example of a hardware configuration of a stimulation adjustment device according to an embodiment. [Diagram 3] FIG. 3 is a flowchart showing an example of an information processing operation by the stimulation adjustment device according to one embodiment. [Figure 4] FIG. 4 shows the results of verifying the relationship between stimulation intensity and electrodermal activity. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following, elements that are the same as or similar to elements already described will be given the same or similar reference numerals, and duplicated descriptions will basically be omitted.

[0013] [Embodiment] (1) Composition (1-1) System 1 is a block diagram showing an example of an overall configuration of a system including a stimulation adjustment device 1 according to an embodiment. The system includes the stimulation adjustment device 1, an EDA measurement section 2, and a stimulation presentation section 3.

[0014] The EDA measurement unit 2 measures the electrodermal activity (EDA) of the user US and outputs a measurement signal. The EDA measurement unit 2 is, for example, a device including an EDA sensor having electrodes attached to the skin surface of the user US. The EDA sensor may measure various types of electrodermal activity. For example, the EDA sensor has a pair of electrodes and measures the potential difference between different points on the skin. The EDA measurement unit 2 performs predetermined processing including amplification, noise removal, AD conversion, etc. on the signal obtained from the EDA sensor, and outputs a measurement signal of the electrodermal activity. The EDA measurement unit 2 is connected to a signal input terminal (not shown) of the stimulation adjustment device 1 via, for example, a signal cable. The EDA measurement unit 2 may transmit the measurement signal to the stimulation adjustment device 1 by short-range wireless communication or the like.

[0015] The stimulus presentation unit 3 presents a tactile stimulus to the user US. The stimulus presentation unit 3 may present any of a wide variety of tactile stimuli. The stimulus presentation unit 3 is, for example, an electrical muscle stimulation (EMS) presentation device having electrodes attached to the skin surface of the user US. The EMS presentation device may be a device that presents an EMS to the user US for a wide variety of purposes, such as an electrical stimulation therapy device, an auxiliary device for sports training, or an auxiliary device for learning to play a musical instrument. The stimulus presentation unit 3 presents a stimulus to the user US according to an instruction signal output from the stimulus adjustment device 1. The instruction signal includes an instruction (command) regarding adjustment of the intensity of the stimulus. The instruction signal may also include other information related to the stimulus, such as a presentation pattern of the stimulus. The stimulus presentation unit 3 is connected to a signal output terminal (not shown) of the stimulus adjustment device 1 via, for example, any signal cable, and receives an instruction signal from the stimulus adjustment device 1. The stimulus presentation unit 3 may receive an instruction signal from the stimulus adjustment device 1 by short-range wireless communication or the like. The stimulation presentation section 3 may be configured to be able to present a stimulation in accordance with an instruction received through a manual operation by a user, in addition to an instruction signal received from the stimulation adjustment device 1.

[0016] The stimulation adjustment device 1 may be implemented as, for example, a microcomputer including a CPU (Central Processing Unit) and a memory. According to one embodiment, the stimulation adjustment device 1 includes a signal input unit 11, an analysis unit 12, a control unit 13, and a signal output unit 14.

[0017] The signal input unit 11 receives a measurement signal of the electrodermal activity of the user US from the EDA measurement unit 2 and passes it to the analysis unit 12.

[0018] The analysis unit 12 analyzes the electrodermal activity of the user US based on the measurement signal input to the signal input unit 11. In one embodiment, the process of analyzing the electrodermal activity includes a process of comparing the value of the electrodermal activity obtained from the measurement signal with a preset threshold and determining whether or not the value of the electrodermal activity exceeds the threshold. The value of the electrodermal activity reflects the degree of mental sweating of the user US, and the degree of mental sweating is considered to be greater as the degree of pain felt by the user US increases. The threshold may be set arbitrarily according to the purpose of presenting the stimulus. For example, the threshold is set based on the value of the electrodermal activity measured in a state where no stimulus is presented to the user US. As an example, the threshold may be set as a value that is a certain percentage or a certain value higher than the reference value of the electrodermal activity measured in a state where no stimulus is presented to the user US. The analysis unit 12 passes the analysis result to the adjustment unit 13. The analysis result can also be said to be a comparison result of whether or not the value of the electrodermal activity exceeds the threshold. The analysis result may include other information. The analysis result may be replaced with other information reflecting the degree of pain of the user US.

[0019] The adjustment unit 13 generates an instruction signal to adjust the intensity of the stimulation presented to the user US according to the analysis result of the electrodermal activity received from the analysis unit 12. The instruction signal includes, for example, information instructing the intensity of the stimulation after adjustment. The intensity of the stimulation can be adjusted by controlling the current, voltage, frequency, pulse width, or the like related to the stimulation. In one embodiment, when the adjustment unit 13 receives an analysis result from the analysis unit 12 indicating that the value of the electrodermal activity exceeds a predetermined threshold, the adjustment unit 13 determines that the intensity of the stimulation presented to the user US needs to be adjusted to be weaker, and generates an instruction signal instructing the adjustment to be made to be weaker.

[0020] The signal output unit 14 outputs the instruction signal generated by the adjustment unit 13. The instruction signal output by the signal output unit 14 is received by the stimulus presentation unit 3, and the stimulus presentation unit 3 adjusts the stimulus to be presented to the user US in accordance with the instruction signal.

[0021] 1 is merely an example. The stimulation adjustment device 1 may include a part of the EDA measurement unit 2 or a part of the stimulation presentation unit 3. The stimulation adjustment device 1 may be integrated with the EDA measurement unit 2 or the stimulation presentation unit 3.

[0022] (1-2) Hardware configuration of the stimulation adjustment device 2 is a block diagram showing an example of a hardware configuration of the stimulation adjustment device 1. In the illustrated example, the stimulation adjustment device 1 includes a CPU 101, a RAM (Random Access Memory) 102, a ROM (Read Only Memory) 103, an input / output interface (input / output I / F) 104, and a peripheral circuit 105. The CPU 101, the RAM 102, the ROM 103, the input / output interface (input / output I / F) 104, and the peripheral circuit 105 are electrically connected by a bus 106.

[0023] CPU 101 controls the overall operation of stimulation adjustment device 1. RAM 102 is, for example, a volatile semiconductor memory, and is used as a working area for CPU 101. ROM 103 is a non-volatile semiconductor memory, and holds programs and control data for controlling stimulation adjustment device 1. CPU 101 can realize the above-mentioned signal input unit 11, analysis unit 12, adjustment unit 13, and signal output unit 14 by expanding, interpreting, and executing the programs stored in ROM 103 in RAM 102.

[0024] The input / output interface 104 is an interface for connecting the stimulation adjustment device 1 and the EDA measurement unit 2, and for connecting the stimulation adjustment device 1 and the stimulation presentation unit 3. The input / output interface 104 includes input / output terminals for analog or digital signals. The input / output interface 104 may include an interface for wired or wireless communication.

[0025] The peripheral circuit 105 includes a timer, a counter, etc. The peripheral circuit 105 may also include an A / D converter.

[0026] Concerning the specific hardware configuration of the stimulation adjustment device 1, components can be omitted, replaced, or added as appropriate depending on the embodiment. For example, the number of CPUs 101 may be two or more instead of one. Also, instead of the CPU 101, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-programmable gate array), or the like may be used.

[0027] (2) Operation Next, an example of the information processing operation of the stimulation adjustment device 1 according to an embodiment will be described. As a premise for the operation, a stimulation presentation unit 3 is associated with the body of the user US. The stimulation presentation unit 3 may be associated with any location on the body of the user US. In the following, a description will be given assuming that the stimulation presented via the stimulation presentation unit 3 is a tactile stimulation, in particular, an electrical muscle stimulation (EMS). For example, an electrode of the stimulation presentation unit 3 that presents the EMS is attached to the forearm of the user US.

[0028] In addition, as a prerequisite for operation, the EDA measurement unit 2 is also associated with the body of the user US. The part of the body where the EDA is measured may be any part where mental sweating can be measured. The part where mental sweating can be measured is, for example, the pads of the fingers, the palms, or the soles of the feet, but is not limited to these. For example, the EDA measurement unit 2 receives potential signals from a pair of electrodes attached to the fingers of the user US, obtains an analog signal representing the potential difference between the two points, and performs predetermined processing such as amplification, noise removal, and AD conversion to transmit the EDA measurement signal to the stimulation adjustment device 1.

[0029] As in the above example, a method of measuring a potential difference between two electrodes without passing a current is called an electric potential method. An example of EDA measured by the electric potential method is a skin potential reflex (SPR), which is known as a transient skin potential response. SPR is known to have a linear relationship with the intensity of a stimulus related to pain sensation or the like. However, this is not limited thereto, and the stimulation adjustment device 1 according to an embodiment is applicable to the measurement of various EDAs. For example, another example of EDA measured by the electric potential method is a skin potential level (SPL), which is considered to reflect an arousal level. EDA may also be measured by an electric current method in which a weak electric current is passed to measure a resistance response or a conductance response of the skin. Examples of EDA measured by the electric current method are a skin resistance level (SRL), a skin resistance response (SRP), a skin conductance level (SCL), and a skin conductance response (SCR).

[0030] Further, here, first, only the EDA measurement unit 2 is started, the EDA is measured in a state where no stimulation is presented to the user US, and the measured value is set as a reference value, thereby setting a threshold value for the user US in advance. For example, the threshold value is set as a value that is an arbitrary percentage (X%) higher than the reference value (for example, 20% higher than the reference value). However, this is only one example, and the threshold value may be set by other methods. In addition, the threshold value may be set for each user, or may be set commonly among multiple users. The threshold value may be calculated and set by a functional unit (not shown) of the stimulation adjustment device 1, or may be set by manual input by an operator.

[0031] 3 is a flowchart showing an example of an information processing operation by the stimulation adjustment device 1 according to an embodiment. The subsequent processing is executed in a state in which the stimulation presentation unit 3 is started in addition to the EDA measurement unit 2 and a stimulation is presented to the user US.

[0032] First, in step S101, the stimulation adjustment device 1 acquires, via the signal input unit 11, the measurement signal output by the EDA measurement unit 2, for example, for a certain period of time.

[0033] In step S102, the stimulation adjustment device 1 analyzes the EDA of the user US based on the acquired measurement signal by the analysis unit 12, and passes the analysis result to the adjustment unit 13. In one embodiment, the stimulation adjustment device 1 compares the EDA value obtained from the measurement signal with a threshold value by the analysis unit 12, and passes the comparison result to the adjustment unit 13 as the analysis result. In a more specific example, the analysis unit 12 calculates a moving average of the EDA value using an analysis window of a predetermined width based on the input measurement signal, and compares the calculated moving average value with a preset threshold value. When measuring EDA using electrodes as described above, if the electrodes are displaced due to body movement, spike noise may occur in the measurement data. By calculating the moving average, the influence of noise caused by such body movement can be suppressed.

[0034] However, the use of the moving average value is merely an example, and other information obtained from the measurement signal may be used. For example, the stimulation adjustment device 1 may compare the maximum value, minimum value, or change width (difference between the maximum value and the minimum value) of the measurement signal obtained for a predetermined analysis window with a threshold value.

[0035] In step S103, the stimulation adjustment device 1 determines whether or not stimulation intensity adjustment is necessary based on the analysis result received from the analysis unit 12 by the adjustment unit 13. If it is determined that stimulation intensity adjustment is necessary (YES), the process proceeds to step S104. If it is determined that adjustment is not necessary (NO), the process ends.

[0036] Here, in one embodiment, when the moving average value of EDA exceeds a threshold, the stimulation adjustment device 1 estimates that the user US is likely to feel pain, and therefore determines that adjustment of the stimulation intensity is necessary. The stimulation adjustment device 1 may immediately determine that adjustment of the stimulation intensity is necessary when even one moving average value exceeds the threshold, or may determine that adjustment of the stimulation intensity is necessary when a predetermined number of moving average values ​​or a predetermined period of time continuously exceed the threshold.

[0037] In step S104, the stimulation adjustment device 1 generates an instruction signal for adjusting the intensity of the stimulation by the adjustment unit 13, and passes it to the signal output unit 14. In one embodiment, the instruction signal includes information instructing the intensity of the stimulation after adjustment. For example, the instruction signal may include information instructing an adjustment rate for the current, voltage, frequency, pulse width, etc. related to the stimulation. The information instructing the adjustment rate is, for example, information instructing to reduce a value by Y%. The instruction signal may include information instructing a value to be reduced, a level to be reduced, a value after adjustment, or a level after adjustment for the current, voltage, frequency, pulse width, etc. related to the stimulation.

[0038] In one embodiment, the system including the stimulation adjustment device 1 adjusts the EMS intensity to be reduced when the moving average value of the EDA measurement value exceeds a threshold. For example, the EMS intensity can be reduced by reducing the current, the voltage, the frequency, or the pulse width. As an example, when the moving average value of the EDA measurement value exceeds a threshold, the EMS intensity is uniformly reduced by a predetermined percentage (for example, 10%) (for example, the current is reduced from 10 mA to 9 mA).

[0039] Alternatively, the system including the stimulation adjustment device 1 may perform adjustment according to the ratio of the excess to the threshold value when the moving average value of the EDA value exceeds the threshold value. For example, the intensity may be reduced by 10% when the moving average value exceeds 110% of the threshold value, and the intensity may be reduced by 20% when the moving average value exceeds 120% of the threshold value. Alternatively, multiple threshold values ​​may be set, and the intensity may be reduced by A% when the EDA value exceeds a first threshold value, and the intensity may be reduced by B% when the EDA value exceeds a second threshold value. This allows adjustment to be performed taking into account the degree of exceedance of the threshold value. What kind of adjustment should be performed according to what kind of analysis result may be arbitrarily set according to the purpose of presenting the stimulation, etc.

[0040] In step S105, the stimulation adjustment device 1 outputs the generated instruction signal by the signal output unit 14. The instruction signal is received, for example, by a control unit (not shown) of the stimulation presentation unit 3. The stimulation presentation unit 3 adjusts the intensity of the electrical stimulation to be presented to the user US in accordance with the instruction signal.

[0041] Figure 4 shows the results of the verification of the relationship between stimulation intensity and electrodermal activity (EDA). In Figure 4, the horizontal axis represents frequency (Hz) and the vertical axis represents EDA value (μS). In this example, EDA sensor electrodes were attached to the index finger and middle finger of the left hand of one subject, and EMS was presented to the right forearm. For the presentation of EMS stimulation, a method was adopted in which the current value was fixed at 12 mA and the pulse width was fixed at 200 μs, and the stimulation intensity was adjusted by changing the frequency (PFM: Pulse Frequency Modulation). The solid line shows the change in the measured EDA value when the frequency was increased to 70 Hz in increments of 10 Hz. It was observed that the EDA value increased as the frequency of EMS stimulation increased. This is presumably because the higher the frequency, the higher the EMS stimulation intensity, which caused the subject to feel stronger pain, which increased psychological sweating and increased the EDA value. The dashed line represents the approximate straight line of the verification results (y = 0.21x + 29.218, R 2 =0.9509).

[0042] In this way, since a roughly linear correlation is observed between the stimulation intensity and the EDA measurement value, it is possible to easily predict the extent to which the EDA measurement value will decrease depending on the amount of adjustment of the stimulation intensity.

[0043] In addition, in application of the stimulation adjustment device 1 according to the embodiment, there is no particular restriction on the relationship between the part where the EDA is measured and the part where the EMS is presented. For example, the EDA measurement unit 2 and the stimulation presentation unit 3 may be attached to the hand of the same side of the user US, or may be attached to different parts, such as one on the hand and the other on the foot.

[0044] In addition, in the application of the stimulation adjustment device 1 according to the embodiment, the tactile stimulation presented to the user US is not limited to electrical stimulation. Since the tactile stimulation may be any stimulation accompanied by pain, in addition to electrical stimulation, a temperature stimulation (temperature that can stimulate pain sensation) or a pressure stimulation accompanied by tightening may be used. When a temperature stimulation is presented, the stimulation presentation unit 3 may be a heat treatment device or a cooling treatment device. By using a Peltier element, a warm or cold stimulation can be easily presented by controlling the current or voltage, and adjustment using an instruction signal is also easy. When a pressure stimulation is presented, the stimulation presentation unit 3 may be a massager or a pressure wave treatment device. Even when a pressure stimulation is presented, the stimulation intensity can be easily adjusted by adjusting the voltage, current, frequency, or pulse width of the control signal.

[0045] (3) Effects As described above in detail, in one embodiment of the present invention, a sensor capable of measuring electrodermal activity is attached to a user, the user's electrodermal activity is analyzed based on the measurement signal, and the intensity of the stimulation presented to the user is adjusted according to the result. This utilizes the fact that when a user feels pain, psychological sweating occurs according to the intensity of the pain, and when psychological sweating occurs, the value of electrodermal activity changes. This makes it possible to automatically reduce the intensity of the stimulation taking into account psychological sweating, which is an involuntary reaction, without the need for the user's self-report or readjustment by the user.

[0046] There are individual differences in how people feel pain, and the way people feel pain may change over time. According to one embodiment, the electrodermal activity is measured in advance without any stimulation being presented to the user, and the measured value is used as a reference value to set the threshold, so that a threshold suitable for each user can be used. Also, by setting the threshold in advance, it is possible to take into account pain that changes over time.

[0047] Depending on the purpose of the stimulation presentation, there may be cases where pain should be reduced as much as possible, and cases where some pain may be tolerated. By setting an appropriate threshold value according to the purpose of the stimulation presentation, it is possible to present the stimulation with reduced burden on the user while achieving the purpose.

[0048] [Other embodiments] It should be noted that the present invention is not limited to the above-described embodiment. For example, the embodiment is not limited to tactile stimulation, and can be applied to various other stimulation presentations. It is known that mental sweating that can be evaluated by EDA is not limited to pain, but is also related to stress, tension, anxiety, and the like. Therefore, the above embodiment can be used in any field where stimulation can be adjusted in consideration of mental sweating. For example, the stimulation adjustment device 1 according to the embodiment may be used to adjust the intensity of visual stimulation, auditory stimulation, olfactory stimulation, or taste stimulation. As an example, the stimulation adjustment device 1 may be configured to monitor the measured value of the EDA of the user US while presenting a visual stimulation to the user US for the purpose of diagnosis, examination, experiment, or the like, and to estimate that the user's stress is high when the EDA value exceeds a threshold value, and to adjust the brightness, saturation, and the like to be reduced.

[0049] The functions of the stimulation adjustment device 1 may be distributed among a plurality of devices, and these devices may perform processing in cooperation with each other. Each function may be realized by using a circuit. The circuit may be a dedicated circuit for realizing a specific function, or may be a general-purpose circuit such as a processor.

[0050] Furthermore, the processing flow described above is not limited to the described procedures. The order of some steps may be swapped, or some steps may be executed in parallel. Also, the series of processes described above do not need to be executed continuously in time, and each step may be executed at any timing.

[0051] The method described above can be stored as a program (software means) to be executed by a computer on a recording medium (storage medium) such as a magnetic disk (floppy (registered trademark) disk, hard disk, etc.), optical disk (CD-ROM, DVD, MO, etc.), semiconductor memory (ROM, RAM, flash memory, etc.), and can also be transmitted and distributed through a communication medium. Note that the program stored on the medium side includes a setting program for configuring software means (including not only the execution program but also tables and data structures) to be executed by a computer in the computer. The computer that realizes the above device reads the program recorded on the recording medium, and in some cases constructs software means by the setting program, and executes the above-described processing by being controlled by this software means. Note that the recording medium referred to in this specification includes not only a storage medium such as a magnetic disk or semiconductor memory provided inside a computer or in a device connected via a network for distribution purposes.

[0052] This invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist thereof at the implementation stage. Also, the respective embodiments may be implemented in appropriate combinations, and in that case, the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combinations selected from a plurality of disclosed constituent elements. For example, if the problem can be solved and the effect can be obtained even when some constituent elements are deleted from all the constituent elements shown in the embodiment, the configuration with these constituent elements deleted can be extracted as an invention.

Explanation of Reference Numerals

[0053] 1...Stimulus adjustment device 2. Electrodermal Activity (EDA) Measurement Unit 3...Stimulus presentation section 11...Signal input section 12…Analysis department 13...Adjustment section 14...Signal output section 101...CPU 102…RAM 103...ROM 104... Input / Output Interface 105...Peripheral circuit 106…Bus

Claims

1. A signal input unit to which a measurement signal of the user's skin electrical activity is input; An analysis unit that analyzes the skin electrical activity by comparing a value obtained using an analysis window of a predetermined width based on the measurement signal with a threshold value and determining whether the value exceeds the threshold value; An adjustment unit that generates an instruction signal for instructing to weaken the intensity of the stimulus presented to the user when it is determined that the value exceeds the threshold value; A signal output unit that outputs the instruction signal A stimulus adjustment device, comprising: wherein the threshold value is set based on the value of the skin electrical activity measured in a state where the stimulus is not presented to the user.

2. The stimulus presented to the user is a tactile stimulus, The measurement signal includes information on the skin electrical activity of the user measured in a state where the tactile stimulus is presented to the user, The stimulus adjustment device according to claim 1.

3. The stimulus adjustment device according to claim 2, wherein the tactile stimulus includes an electrical muscle stimulus, a temperature stimulus, or a pressure sensation stimulus.

4. The stimulus adjustment device according to any one of claims 1 to 3, wherein the adjustment unit generates an instruction signal for instructing to reduce a value of current, voltage, frequency, or pulse width related to the stimulus presented to the user.

5. A stimulus adjustment method executed by a computer, comprising: Obtaining a measurement signal of the user's skin electrical activity; Analyzing the skin electrical activity by comparing a value obtained using an analysis window of a predetermined width based on the measurement signal with a threshold value and determining whether the value exceeds the threshold value; Generating an instruction signal for instructing to weaken the intensity of the stimulus presented to the user when it is determined that the value exceeds the threshold value; Outputting the instruction signal A stimulus adjustment method, wherein the threshold value is set based on the value of the skin electrical activity measured in a state where the stimulus is not presented to the user.

6. A stimulus adjustment program that causes a computer to execute the processing by each unit of the stimulus adjustment device according to any one of claims 1 to 4.

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