Calibration device, pseudo force sense presentation system, calibration method, pseudo force sense presentation method, and program

Abstract

The present invention presents a pseudo force sense that is less likely to be affected by individual differences or contact states. A calibration device 10 according to the present disclosure comprises a reception unit 11 and a calibration unit 12. The calibration device 10 receives input of a target skin deformation pattern x. The target skin deformation pattern x is a signal obtained by synthesizing a plurality of sine wave signals with a phase difference. The target skin deformation pattern x has a signal waveform in which position or velocity is asymmetric. The calibration unit 12 calibrates, using predetermined calibration data, the target skin deformation pattern x received by the reception unit 11.

Description

Calibration device, simulated force feedback system, calibration method, simulated force feedback method, and program

[0001] This disclosure relates to a technology for perceiving a simulated sense of force.

[0002] A device has been proposed that controls an actuator to present a pseudo-force sensation, such as the illusion of traction force (see, for example, Non-Patent Document 1).

[0003] Tomohiro Amemiya, Shinya Takamura, Sho Ito, and Hiroaki Gomi, "A device that creates the sensation of being pulled when pinched with fingers: 'Burunavi 3'", 2014, NTT Technical Journal, Vol. 26, No. 9, pp. 23-26.

[0004] However, the device disclosed in Non-Patent Document 1, even with the same control signal, could have its output altered depending on the device's configuration, how it was held, and individual physical differences, which could hinder the presentation of simulated force. To present the desired simulated force, the control signal needed to be adjusted according to the situation, and this required estimating a complex dynamics model.

[0005] Therefore, this disclosure aims to provide a technology that presents a simulated force sensation that is less affected by individual differences and contact conditions.

[0006] The calibration device of this disclosure includes a receiving unit that receives input of a target skin deformation pattern having a signal waveform with asymmetrical position or velocity, which is a signal obtained by synthesizing a plurality of sinusoidal signals with a phase difference, and a calibration unit that calibrates the target skin deformation pattern using predetermined calibration data.

[0007] According to the calibration device of the embodiment of this disclosure, it is possible to present a simulated force sensation that is less affected by individual differences and contact conditions.

[0008] Figure 1 is an illustrative diagram illustrating skin deformation in a simulated force feedback device. Figure 2 is a diagram showing an example of the functional configuration of the simulated force feedback system according to this embodiment. Figure 3 is a diagram showing an example of the processing flow of the simulated force feedback system according to this embodiment. Figure 5 is a diagram showing an example of how to attach the device to the user's simulated force feedback target area. Figure 6 is a diagram showing an example of the functional configuration of the simulated force feedback system according to a modified version of this embodiment. Figure 7 is a diagram showing an example of the evaluation experiment results of the simulated force feedback system according to this embodiment. Figure 8 is a diagram showing an example of the functional configuration of the computer.

[0009] <Technology of Focus> Conventional methods for controlling pseudo-force sensation have often focused on the output of the device that presents pseudo-force sensation (hereinafter also referred to as the "pseudo-force sensation presenting device") itself, or on the control signals which are input signals to the pseudo-force sensation presenting device. In this disclosure, we focus on the contact surface between the pseudo-force sensation presenting device and the user receiving the pseudo-force sensation, that is, the skin deformation that occurs on the user's skin that touches the contact part of the pseudo-force sensation presenting device. In particular, we focus on the asymmetry of the position or velocity of the skin deformation in the user's skin deformation.

[0010] Figure 1 is an illustrative diagram illustrating skin deformation in a simulated force feedback device. The left side of Figure 1 shows a user pinching a contact area, which has a rectangular parallelepiped shape and outputs vibrational stimuli, between their fingers. The right side of Figure 1 shows a waveform illustrating skin deformation near the contact area on the upper pinching finger, with time on the horizontal axis and position (amplitude) on the vertical axis in this example. For example, the waveform shown in Figure 1 is asymmetrical in amplitude and period with respect to the time axis (horizontal axis). As shown in the waveform in Figure 1, when the amplitude, which is the displacement, is larger on the R side (positive direction on the vertical axis) than on the L side (negative direction on the vertical axis), the user α experiences a simulated force sensation of being pulled to the R side (left direction in the perspective of the left side of the diagram in Figure 1) by the contact area. A similar trend is also observed for velocity, as will be discussed later.

[0011] This disclosure focuses on the asymmetry of position or velocity within skin deformation. As a result, as shown in the <Evaluation Experiment> described below, a specific target skin deformation pattern was identified that produces pseudo-force sensation without bias towards individual differences. Furthermore, even if the control signal to the pseudo-force presentation device is the same, skin deformation will vary considerably depending on the configuration of the pseudo-force presentation device and how the user grasps (holds) the device. Therefore, the pseudo-force presentation system of this disclosure incorporates a process for data calibration. This makes it possible to present pseudo-force sensation that is less affected by individual differences and contact conditions.

[0012] <Embodiments> Embodiments of the present disclosure will be described in detail below. Components having the same function will be numbered the same, and redundant explanations will be omitted.

[0013] Figure 2 is a diagram showing an example of the functional configuration of the pseudo-force feedback system according to this embodiment. As shown in Figure 2, the pseudo-force feedback system 1 of this embodiment includes a calibration device 10 and a presentation device 20. The presentation device 20 corresponds to the pseudo-force feedback system described above. The calibration device 10 includes a receiving unit 11 and a calibration unit 12. The presentation device 20 includes a drive unit 21 and a contact unit 22.

[0014] The calibration device 10 takes the target skin deformation pattern and calibration data as input and outputs a control signal to control the presentation device 20. The presentation device 20 takes the control signal as input, drives the drive unit 21, and outputs vibration from the contact part 22. Since this vibration is a vibration stimulus to the user, in this disclosure, the vibration output from the contact part 22 is also referred to as "vibration stimulus." In this disclosure, "outputting a vibration stimulus" is also referred to as "presenting pseudo-force sensation." The drive unit 21 is a so-called actuator. The pseudo-force sensation presentation system 1 performs the pseudo-force sensation presentation method of this embodiment by implementing the processing flow illustrated in Figure 3. Hereinafter, with reference to Figure 3, an example of the processing flow of the pseudo-force sensation presentation method in the pseudo-force sensation presentation system 1 will be described in order of procedure.

[0015] The reception unit 11 receives an input of a target skin deformation pattern which is a signal obtained by synthesizing a plurality of sine wave signals with a phase difference and has a signal waveform in which the position or speed is asymmetric (step S11). Specifically, when x is the target skin deformation pattern (hereinafter also referred to as "target skin deformation pattern"), A is the amplitude, φ is the phase difference, ω is the angular velocity, t is the time, and i is an integer of 1 or more, the desired target skin deformation pattern x is set as a composite signal based on a sine wave as shown in the following equation. The reception unit 11 receives an input of this target skin deformation pattern x. The received target skin deformation pattern x is transmitted to the calibration unit 12. When ω is a constant, ω in the above formula (1) ｉ can also be expressed as iω (that is, i × ω).

[0016] The calibration unit 12 calibrates the target skin deformation pattern x using predetermined calibration data (step S12). The calibrated data is used as a control signal x which is a signal for controlling the presentation device 20. Therefore, from another perspective, it can be said that the calibration unit 12 generates the control signal x ｃ ｃ

[0017] In this embodiment, the calibration data is measured in advance by the following method. Here, let G(s) be a dynamics model between, for example, a part that outputs a vibration stimulus corresponding to the contact part 22 (presents pseudo-force sensation) and a part of the user α that receives a pseudo-force sensation stimulus such as a finger (hereinafter also referred to as "pseudo-force sensation target part α1"). The calibration data is a feature amount calculated using a predetermined sine wave signal and a frequency response signal for the sine wave signal. Specifically, A ｉｎ is the amplitude of the input sine wave signal, A ｏｕｔ is the amplitude of the output (frequency response) accompanying the input of A ｉｎ to G(s), and φ ｄ is the phase difference between the input signal and the output signal. In this case, the sine wave signal for each i is input to the presentation device 20 and the respective outputs are measured, and using the following equation, the gain |G(jω ｉ )| and the phase delay ∠G(jω ｉ ), which are feature amounts, are calculated. Calculated gain | G(jω ｉ )|, and phase lag ∠G(jω ｉ This is the calibration data for the simulated force feedback system 1. The calculated calibration data is input to the calibration unit 12.

[0018] The calibration unit 12 uses the input target skin deformation pattern x and calibration data to generate a control signal x from the following equation: ｃ Generates. Generated control signal x ｃ This is transmitted to the display device 20.

[0019] The display device 20 receives a control signal x ｃ Using this, the device outputs a vibration stimulus (step S20). That is, the presentation device 20 outputs a control signal x ｃ The drive unit 21 is driven using this method, and vibration stimuli are output from the contact part 22 by the drive of the drive unit 21. For example, a user α whose finger is touching the contact part 22 will receive vibration stimuli (be presented with pseudo-force sensation) through the contact part 22. In this case, it is preferable to fix the presentation device 20 to the skin so that accurate and desired skin deformation can be received. For example, as shown in Figure 4, a hard part such as a nail or bone (hereinafter also referred to as "fixing target area α2") located on the opposite side of the pad of the finger receiving the vibration stimuli is fixed to the housing 23 of the presentation device 20 by a structure using adhesive force such as double-sided tape or a structure using frictional force such as surface roughness (hereinafter also referred to as "fulcrum structure 24"). That is, it is preferable to configure the fulcrum structure 24 to function as a fulcrum.

[0020] In this example, the presentation device 20 has a housing 23 to which a contact part 22 that outputs a vibration stimulus for user α to touch is attached, as shown in Figure 4. Part of the drive unit 21 is incorporated inside the contact part 22. The housing 23 in this example has a box-shaped structure that is open in at least one direction to allow insertion of the user's finger, and the contact part 22 is attached to the area corresponding to the inner bottom wall. In this example, user α brings the pseudo-force sensation target area α1, which corresponds to the pad of the finger, into contact with the contact part 22. The housing 23 in this example has a shape that accepts finger insertion and can cover both the pad and the nail of the finger. When user α brings the pseudo-force sensation target area α1 into contact with the contact part 22 at a position opposite the contact part 22, the housing 23 fixes the fixing target area α2 (nail in Figure 4), which is near the pseudo-force sensation target area α1 and is a part that is rigider than the pseudo-force sensation target area α1, by a pivot structure 24. The pivot structure 24 acts as a pivot point when the contact portion 22 vibrates. The structure of the housing 23 shown in Figure 4 is merely an example, and it is not limited to a box shape; other shapes and configurations are also acceptable as long as the pivot structure 24 acts as a pivot point when the contact portion 22 vibrates. For example, the housing 23 in Figure 4 covers the fingertip, nail, and palm, but it is not limited to this. For example, it may not cover the fingertip, but surround the finger and cover the nail and palm. Also, the housing 23 may be a spherical shape with a part of it open, or it may be a belt-shaped configuration that covers the circumference of the finger.

[0021] As described above, the pseudo-force feedback system 1 of this disclosure focuses on skin deformation that occurs at the contact surface between the pseudo-force feedback device and the skin of user α touching it. More specifically, it focuses on the asymmetry of the position or velocity of the skin deformation. Furthermore, it can vary considerably depending on the configuration of the pseudo-force feedback device and how user α grasps (holds) the device. In order to provide the desired skin deformation, the pseudo-force feedback system 1 of this disclosure employs a method of calibrating the model parameters between the presentation device 20 and user α using a simple method with a sine wave, without estimating complex model parameters. With this configuration, the pseudo-force feedback system 1 can provide pseudo-force feedback that is less affected by individual differences and contact conditions.

[0022] <Modification> The pseudo-force feedback system of this disclosure may be configured as shown in Figure 5, pseudo-force feedback system 1B. The pseudo-force feedback system 1B includes a calibration device 10, a presentation device 20, and a measuring device 30. The measuring device 30 includes a reception unit 31, a measurement unit 32, and a calibration data calculation unit 33. In the pseudo-force feedback system 1, calibration data had to be acquired in advance. The pseudo-force feedback system 1B has the function of calculating calibration data by measuring the movement of the pseudo-force feedback target area α1 of user α placed on the contact unit 22. Therefore, it is configured so that the calculated calibration data can be directly input to the calibration device 10. The pseudo-force feedback system 1B performs the pseudo-force feedback method of this embodiment by implementing the processing flow illustrated in Figure 6. Hereinafter, with reference to Figure 6, an example of the processing flow of the pseudo-force feedback method in the pseudo-force feedback system 1B will be explained, focusing on the procedure of the difference from Figure 3.

[0023] After step S11, the reception unit 31 receives input of the target skin deformation pattern x, similar to the reception unit 11 (step S31). The received target skin deformation pattern x is transmitted to the measurement unit 32.

[0024] Next, the measurement unit 32, based on the received target skin deformation pattern x, A ｉｎ，ｉ The following is input to the display device 20, and the movement of the pseudo-force sensor α1 at the contact portion 22, i.e., the frequency response A ｏｕｔ，ｉ , phase difference φ ｉ Measure (step S32). A ｉｎ，ｉ , A ｏｕｔ，ｉ , phase difference φ ｉ This is transmitted to the calibration data calculation unit 33.

[0025] Next, the calibration data calculation unit 33 performs A ｉｎ，ｉ , A ｏｕｔ，ｉ , phase difference φ ｉ Based on this, calibration data is calculated from the above-mentioned equations (2) and (3) (step S33). The calculated calibration data is transmitted to the calibration device 10 and used in the process of step S12 described above.

[0026] As described above, the modification according to the embodiment of the present disclosure has been explained. The function corresponding to the measuring device 30 in the pseudo-force sensation presentation system 1B may be configured to be incorporated into either the calibration device 10 or the presentation device 20.

[0027] In the embodiments and modifications of the present disclosure, the various processes described are not only executed in time series according to the described order, but may also be executed in parallel or individually according to the processing capacity of the device that executes the processes or as necessary.

[0028] Furthermore, the device of the present disclosure or the method of the present disclosure may also have a device (terminal) for use via a network (telecommunication line). The "device (terminal) for use" may be provided with functions necessary for obtaining the effects of the device of the present disclosure and the method of the present disclosure (for example, control function, decoding function, restoration function, input / output function, etc.).

[0029] <Evaluation Experiment> Using the pseudo-force sensation presentation system 1 of the present disclosure, the direction of the pseudo-force sensation perceived by the subject for a specific target skin deformation pattern was investigated. Specifically, an evaluation experiment was conducted in which the subject was asked to answer the direction (left / right) in which they felt the pseudo-force sensation with respect to the output vibration stimulus.

[0030] In this evaluation experiment, a signal obtained by synthesizing two sine waves shown in the following formula was output as a vibration stimulus to the subject. In Equation (5), A １ = 0.4 mm, A ２ = 0.1 mm, ω = 40 Hz, and the vertical pressing force was 0.2 N. The vibration position and contact force of the presentation device 20 and the skin (pseudo-force sensation target portion α1) were measured using a laser displacement meter, a force sensor, and a camera. Note that they were fixed with double-sided tape so that the contact surface between the contact portion 22 and the skin would not slip. Also, in order to adopt a structure corresponding to the fulcrum structure 24 in FIG. 4, a claw (corresponding to the fixed target portion α2 shown in FIG. 4) and a housing (corresponding to the housing 23 in FIG. 4) were fixed using double-sided tape.

[0031] The study involved 10 subjects (male and female). The phase difference φ was varied in 45-degree increments across eight phase conditions, ranging from 0 to 315 degrees. Vibration stimuli were output 20 times for each phase, for a total of 160 times, in a random order. The response method employed a two-choice forced selection system, requiring subjects to choose either left or right, even if they could not clearly distinguish between the two. A 5-second interval was provided between each response. The vibration stimuli underwent calibration processing equivalent to that of a calibration device 10 for each subject.

[0032] Figure 7 shows an example of the results from the evaluation experiment described above. The horizontal axis represents the phase difference φ, and the vertical axis shows the frequency of left and right responses. The vertical axis is based on 0.5, with a value greater than 0.5 indicating that more subjects answered "right," and a value less than 0.5 indicating that more subjects answered "left." In Figure 7, for reference, the waveforms of position and velocity are shown at the top of the graph for four different phase differences φ: 0°, 90°, 180°, and 270°.

[0033] As shown in Figure 7, with waveforms where the amplitude of position is asymmetric (phase difference φ of 90 degrees or 270 degrees), the responses were close to 0 or 1, confirming that a clear pseudo-force sensation occurs. Even with waveforms where the amplitude of velocity is asymmetric (phase difference φ of 0 degrees or 180 degrees), the responses were close to 0.6 or 0.4, which are clearly distinguishable from 0.5, confirming that there is a tendency for pseudo-force sensation to occur. The effects of asymmetry in acceleration and jerk were similarly examined, but no tendency for pseudo-force sensation to occur was observed. From these results, it was confirmed that pseudo-force sensation occurs with skin deformation that is asymmetric in position or velocity. In particular, in the above equation (1), if i is set to 1 or 2, ω １ Let ω be 40Hz. ２ Let 80Hz be used, φ １ Let φ be 0. ２ It was confirmed that setting the angle to 90° or 270° generates a greater pseudo-force sensation. Implementation in pedestrian navigation systems and mobile devices such as game controllers is also expected.

[0034] [Processors, Programs, Recording Media] The functions realized by the components described herein may be implemented in a circuitry or processing circuitry, including general-purpose processors, application-specific processors, integrated circuits, ASICs (Application Specific Integrated Circuits), CPUs (a Central Processing Unit), conventional circuits, and / or combinations thereof, programmed to realize the functions described herein. A processor includes transistors and other circuits and is considered a circuitry or processing circuitry. A processor may be a programmed processor that executes a program stored in memory.

[0035] In this specification, circuitry, unit, and means are hardware programmed to perform or execute the functions described herein. Such hardware may be any hardware disclosed herein, or any hardware known to be programmed to perform or execute the functions described herein.

[0036] If the hardware is a processor that is considered to be a type of circuitry, then the circuitry, means, or unit is a combination of hardware and software used to constitute the hardware and / or processor.

[0037] The various processes described above can be carried out by loading a program that executes each step of the above method into the recording unit 2020 of the computer 2000 shown in Figure 8, and then causing the control unit 2010, input unit 2030, output unit 2040, display unit 2050, etc. to operate.

[0038] The program describing this process can be recorded on a computer-readable recording medium. Any computer-readable recording medium can be used, such as a magnetic recording device, optical disc, magneto-optical recording medium, or semiconductor memory.

[0039] Furthermore, this program may be distributed, for example, by selling, transferring, or lending portable recording media such as DVDs or CD-ROMs on which the program is recorded. Alternatively, the program may be stored in the storage device of a server computer and distributed by transferring the program from the server computer to other computers via a network.

[0040] A computer executing such a program may, for example, first store the program recorded on a portable storage medium or a program transferred from a server computer in its own storage device. Then, when processing is to be executed, the computer reads the program stored on its own storage medium and executes the processing according to the read program. Alternatively, the computer may directly read the program from the portable storage medium and execute the processing according to that program, or it may sequentially execute the processing according to the received program each time a program is transferred to it from a server computer. Furthermore, the processing may be executed using a so-called ASP (Application Service Provider) type service, where the processing function is realized only by issuing execution instructions and obtaining results, without transferring the program from the server computer to this computer.In addition, the processing may be executed using a so-called SaaS (Software as a Service) type service, where a part of the server computer is made available to the user along with the program. Furthermore, the term "program" in this form includes information used for processing by an electronic computer that is equivalent to a program (data, etc., that is not a direct instruction to the computer but has the property of defining the processing of the computer).

[0041] Furthermore, in this configuration, the device is configured by executing a predetermined program on a computer, but at least a part of these processes may be implemented in hardware.

Claims

1. A calibration device comprising: a receiving unit that receives input of a target skin deformation pattern having a signal waveform with asymmetrical position or velocity, which is a signal obtained by synthesizing multiple sinusoidal signals with a phase difference; and a calibration unit that calibrates the target skin deformation pattern using predetermined calibration data.

2. When x is the target skin deformation pattern, A is the amplitude, φ is the phase difference, ω is the angular velocity, t is time, and i is an integer of 1 or more, the skin deformation pattern is given by the following equation The calibration device according to claim 1, which can be calculated using [a specific method / tool].

3. The calibration device according to claim 1, wherein the calibration data is a feature quantity calculated using a predetermined sinusoidal wave signal and a frequency response signal for the sinusoidal wave signal.

4. A pseudo-force feedback system comprising a calibration device and a presentation device, wherein the calibration device includes a receiving unit that receives input of a target skin deformation pattern having a signal waveform with asymmetrical position or velocity, which is a signal obtained by synthesizing a plurality of sinusoidal signals with a phase difference, and a calibration unit that calibrates the target skin deformation pattern using predetermined calibration data, and the presentation device outputs vibration using the calibrated target skin deformation pattern.

5. The pseudo-force presentation system according to claim 4, wherein the presentation device has a housing equipped with a contact portion that outputs vibration for the user to touch, and the housing has a pivot structure at a position opposite to the contact portion for fixing a fixed target portion which is in the vicinity of the pseudo-force target portion and is more rigid than the pseudo-force target portion when the user's pseudo-force target portion is brought into contact with the contact portion.

6. A calibration method comprising: a reception unit of a calibration device receiving input of a target skin deformation pattern having a signal waveform with asymmetrical position or velocity, which is a signal obtained by synthesizing a plurality of sinusoidal signals with a phase difference; and a calibration unit of the calibration device calibrating the target skin deformation pattern using predetermined calibration data.

7. A method for presenting simulated force feedback, wherein the receiving unit of a calibration device receives input of a target skin deformation pattern having a signal waveform with asymmetrical position or velocity, which is a signal obtained by synthesizing multiple sinusoidal signals with a phase difference; the calibration unit of the calibration device generates a control signal using the target skin deformation pattern and predetermined calibration data; and the presentation device outputs vibration using the control signal.

8. A program for causing a computer to operate the calibration device described in claim 1, or the pseudo-force feedback system described in claim 5.

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