Mechanical model of a finger and vibration measuring device

Abstract

Providing technology that contributes to the objective evaluation of vibration-generating devices. [Solution] The finger model 2 has a structure in which three stages of mass and viscoelastic material connected in series are stacked. In the mechanical coupler 100, the finger model 2 is housed in a housing 50, its lower end is fixed to the floor surface 50b, and a part of the mass 11 that forms its upper end protrudes from an opening 50a formed in the upper part of the housing 50. An acceleration sensor 60 is attached to the side of the mass 31, and a measuring instrument 80 is connected to the acceleration sensor 60. The device HD to be measured is placed on the mass 11 and connected to the transmitter 70, and the sensitivity of the device HD is measured by the mechanical coupler 100. When vibration is applied to the mass 11, the response of the finger model 2 is equivalent to the response of a human finger. By using the mechanical coupler 100, the sensitivity corresponding to the mounting load of various devices on the finger can be measured and objectively evaluated using the same standard.

Description

Technical Field

[0001] The present invention relates to a mechanical model of a finger that simulates a human finger, and a vibration measuring device provided with the same.

Background Art

[0002] As one of the virtual reality (VR) technologies, haptics technology that gives a user an appropriate vibration to provide a feeling as if touching an object that does not exist at the location has attracted attention. In recent years, research has been actively conducted to present various tactile sensations by utilizing the vibration sensation of fingers.

[0003] For example, not only is vibration applied to the fingertip to pursue realism, but it is also becoming possible to use technologies such as indicating a direction by presenting a pulling force (giving a directional guidance experience) by vibration and reproducing the tactile sensation of a texture. In addition, a technology that reproduces the tactile sensation of an object touched by a certain person and gives another person who has not actually touched the object a feeling as if touching the same object is also becoming available. Patent Document 1 discloses a technology for transmitting information regarding the tactile sensation measured on the slave device side to the master device side in a master-slave type endoscopic surgical system that enables an approach to a diseased part without making a large incision in the patient's body, and transmitting the tactile sensation to the surgeon by more accurately reproducing the target vibration waveform.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] A wide variety of devices (vibrators, actuators, etc.) such as LRAs (linear resonant actuators), piezoelectric and electrodynamic types are used to present the vibration sensation described above, and the device manufacturing industry is advancing its research and development in these areas.

[0006] However, there is no established mechanical coupler for evaluating such a wide variety of devices, and currently, it is not possible to perform performance evaluations using the same criteria that simulate the mechanical impedance (load) of a finger. Since the performance of the devices depends on the mechanical impedance of a finger, a mechanical coupler that simulates the mechanical impedance of a finger is necessary to compare these devices. The device described in Patent Document 1 above uses a built-in acceleration sensor to perform measurements specific to a particular application and cannot measure a wide variety of devices.

[0007] This invention has been made in view of these problems, and aims to provide a technology that contributes to the objective evaluation of vibration-applying devices. [Means for solving the problem]

[0008] To solve the above problems, the present invention employs the following mechanical finger model and vibration measuring device equipped therewith. Note that the following statements in parentheses are merely examples, and the present invention is not limited thereto.

[0009] In other words, the mechanical finger model of the present invention is a mechanical finger model that simulates a human finger, and comprises a plurality of masses and a number of viscoelastic units, one or more of which are made of viscoelastic materials, with the masses and viscoelastic units being connected alternately, the viscoelastic units forming the ends being fixed to a rigid body, and the mass furthest from the rigid body corresponding to a point mass on the surface of the finger.

[0010] In other words, the mechanical model of a finger has a structure in which multiple stages are stacked, each in which a mass and a viscoelastic unit are connected in series, with the viscoelastic units at the ends fixed to a rigid body. As an example, Figure 1 shows a three-stage mechanical model of a finger in which the mass of the first stage corresponds to a point mass on the surface of the finger, and the viscoelastic unit of the third stage forms the end and is fixed to a rigid body.

[0011] In the illustrated example, the mass and the viscoelastic unit are connected in a line, but the series connection between the mass and the viscoelastic unit refers to the series connection in the concept of representing the mechanical model of the finger as an equivalent circuit (series connection from a mechanical equivalent circuit perspective), and is not limited to being in a series (line) in terms of position. For example, the first stage mass forms the center of the mechanical model of the finger, and the units are connected in a sequence that surrounds it, along its radial direction (outward), in the order of first stage mass → first stage viscoelastic unit → second stage mass → second stage viscoelastic unit → third stage mass → third stage viscoelastic unit.

[0012] Furthermore, the viscoelastic body included in the mechanical model of the finger in this embodiment may be an elastic body (e.g., a spring) and a viscous body (e.g., a dashpot) connected in parallel, as shown in Figure 2(A); an elastic body and a viscous body connected in series, as shown in Figure 2(B); or integrally formed from a material having both elastic and viscous properties (e.g., rubber), as shown in Figure 2(C). Alternatively, some or all of the multiple viscoelastic bodies may be composed of either an elastic body or a viscous body alone. Each individual viscoelastic body unit is composed of one or more such viscoelastic bodies.

[0013] More preferably, in the mechanical model of a finger according to the above-described embodiment, the model comprises three masses and three viscoelastic units (in other words, a three-tiered configuration), wherein a first viscoelastic unit is connected to a first mass corresponding to the point mass, a second mass is connected to the first viscoelastic unit, a second viscoelastic unit is connected to the second mass, a third mass is connected to the second viscoelastic unit, and a third viscoelastic unit is connected to the third mass. More preferably, the first mass is 0.1 to 1.0 g, the second mass is 1 to 10 g, the third mass is 1 to 10 g, the elastic stiffness of the viscoelastic unit is 5000 to 9000 N / m for the first viscoelastic unit, 5000 to 9000 N / m for the second viscoelastic unit, and 1000 to 3000 N / m for the third viscoelastic unit, and the mechanical resistance of the viscoelastic unit is 1 to 5 Ns / m for the first viscoelastic unit, 0 to 1 Ns / m for the second viscoelastic unit, and 1 to 10 Ns / m for the third viscoelastic unit.

[0014] The finger mechanical model simulates a human finger and is designed to produce a response equivalent to the average value of all fingers measured, based on the results of finger mechanical impedance measurements conducted on multiple individuals. In other words, by adopting the above configuration, the finger mechanical model possesses the response characteristics to vibrations of a human finger. Therefore, by using the finger mechanical model, it becomes possible to objectively evaluate the quality and performance of haptic devices without using human fingers.

[0015] In addition, all of the finger mechanical models described above have a structure in which the same number of mass and viscoelastic units are alternately connected, and the viscoelastic end bodies are fixed to rigid bodies. However, multiple such finger mechanical models (for example, two) may be placed in close proximity and treated as a single integrated finger mechanical model.

[0016] Furthermore, the vibration measuring device of the present invention includes a mechanical finger model in any of the above-described embodiments and measures the response of the mechanical finger model to the vibration of the device to be measured (haptic device). During measurement, the device to be measured is placed on the mass forming one end of the mechanical finger model, i.e., the first stage mass, as shown in Figure 3.

[0017] More preferably, the vibration measuring device described above further comprises a housing that accommodates a mechanical model of a finger, fixing a viscoelastic body unit that forms the end, while allowing a portion of the mass corresponding to the above-mentioned point mass to protrude from an opening, and an acceleration sensor attached to the side of any of the masses. In the example shown in Figure 3(A), the acceleration sensor is attached to the side of the third stage of mass, but it may be attached to the side of any other stage of mass instead.

[0018] Alternatively, the vibration measuring device described above further comprises a housing that accommodates a mechanical model of a finger, fixing a viscoelastic unit that forms the end of the model while allowing a portion of the mass corresponding to the point mass to protrude from an opening, and a sensor for detecting force or pressure, inserted at any position between the mass corresponding to the point mass and the part of the housing to which the viscoelastic unit forming the end is fixed. In the example shown in Figure 3(B), the force sensor is inserted between the third-stage mass and the viscoelastic unit, but it may be inserted at other positions.

[0019] In a vibration measuring device, a mechanical model with response characteristics to the vibration of a human finger is used to measure the response of a device when it receives vibration. At this time, by attaching the sensor to a location on the mechanical model of the finger that corresponds to a human receptor, it is possible to link the measurement to human sensory input. Therefore, using any of the above-described vibration measuring devices, it is possible to measure the sensitivity corresponding to the mechanical impedance of various haptic devices when they are worn on a human finger. Furthermore, the sensitivity of various haptic devices can be measured using the same standard, making it possible to objectively evaluate or compare the performance of these devices.

Advantages of the Invention

[0020] As described above, according to the present invention, it becomes possible to objectively evaluate a device that gives vibration.

Brief Description of the Drawings

[0021] [Figure 1] It is a diagram showing the configuration of a mechanical model of a finger for solving problems. [Figure 2] It is a diagram showing variations in the configuration of a viscoelastic body. [Figure 3] It is a diagram showing an example of the attachment position of a sensor in a vibration measuring device. [Figure 4] It is a diagram showing a configuration example of a finger mechanical model 1 of an embodiment. [Figure 5] It is a diagram showing a configuration example of a mechanical coupler 100 of the first embodiment provided with a finger mechanical model 2. [Figure 6] It is a flowchart showing an example of a procedure of sensitivity measurement processing executed by the mechanical coupler 100. [Figure 7] It is a diagram showing a configuration example of a mechanical coupler 200 of the second embodiment. [Figure 8] It is a diagram showing configuration examples of finger mechanical models 3 and 4 of other embodiments.

Embodiments for Carrying Out the Invention

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the following embodiments are preferred examples, and the present invention is not limited to this example.

[0023] 〔Configuration of Finger Mechanical Model〕 FIG. 4 is a diagram showing a configuration example of a finger mechanical model 1 of an embodiment. The finger mechanical model 1 simulates a human finger and has a structure consisting of three stacked stages in which a mass and a viscoelastic unit consisting of one or more viscoelastic materials are connected in series. In other words, the finger mechanical model 1 has three masses and three viscoelastic units, and the masses and viscoelastic units are connected alternately in series, one at a time. Furthermore, the viscoelastic units included in each stage have a structure (Voigt model) in which viscous materials such as dampers and elastic materials such as springs are connected in parallel.

[0024] Specifically, as shown in Figure 4(A), the first stage 10 consists of a mass 11 connected in parallel with a spring 12 and a damper 13 (a viscoelastic unit consisting of one viscoelastic material) connected in series, the second stage 20 consists of a mass 21 connected in parallel with a spring 22 and a damper 23 (a viscoelastic unit consisting of one viscoelastic material) connected in series, and the third stage 30 consists of a mass 31 connected in parallel with a spring 32 and a damper 33 (a viscoelastic unit consisting of one viscoelastic material) connected in series. These three stages 10, 20, and 30 are stacked in series, and the unconnected end of the third stage 30 is fixed to a sufficiently heavy rigid body (in other words, the mass 31 is connected to the rigid body via the spring 32 and damper 33), thereby forming the mechanical model 1 of the finger. From a different perspective, of the three masses 11, 21, and 31, mass 11 is the furthest from the rigid body (it travels the longest distance through mechanical elements and passes through the most mechanical elements).

[0025] Incidentally, the three-stage configuration of the finger mechanical model 1 is based on the results of measurements of the mechanical impedance of fingers conducted prior to the development of this model. Although the details of the measurement are omitted here, when 20 hands from 10 adults with normal fingers were collected and the mechanical impedance of the fingers as seen from the vibrator was measured in the range of 20 to 2000 Hz, dips (anti-resonances) in the mechanical impedance frequency characteristics were found around 70 Hz, 250 Hz, and 800 Hz. From this, it can be estimated that in the range of 20 to 2000 Hz, at least three masses, three elastic components, and three resistive components are vibrating at different speeds, and therefore the three-stage configuration described above was adopted. In the finger mechanical model 1, mass 11 corresponds to a point mass on the surface of the finger that the vibrator contacts.

[0026] The finger mechanical model 1 can simulate the output when a vibrating device is worn on a human finger by appropriately selecting the constants (characteristic values) of each mechanical element that constitutes it. Figure 4(B) shows a suitable example of the constants of each mechanical element that constitutes the finger mechanical model 1. When the absolute value and phase of the mechanical impedance were calculated using these constants and the equivalent circuit corresponding to the structure in Figure 4(A), they were in general agreement with the measured values ​​(average value of all fingers). That is, when vibration is applied to the mass 11 of the finger mechanical model 1 to which these constants are applied, the response of this mechanical model 1 is equivalent to the response of the finger in the above measurement (average value of all fingers), and consequently, the response of a human finger.

[0027] In Figure 4(B), the constants (elastic stiffness) of each elastic body correspond to the elastic stiffness of the viscoelastic unit to which each elastic body belongs, and the constants (mechanical resistance) of each viscous body correspond to the mechanical resistance of the viscoelastic unit to which each viscous body belongs. For example, the elastic stiffness of elastic body 12 and the mechanical resistance of viscous body 13 are preferred values ​​for the elastic stiffness and mechanical resistance of the entire viscoelastic unit of the first stage 10.

[0028] By the way, in Figure 4(B), the mechanical resistance of the viscous material 23 is zero (0 Ns / m). That is, in the mechanical model of the finger to which these constants are applied, the viscoelastic material in the second stage 20 is a combination of the elastic material 22 and the viscous material 23 with zero mechanical resistance (0 Ns / m) connected in parallel. In other words, as shown in Figure 4(C), the second stage 20 does not contain any viscous material, and only the elastic material 22 is connected to the mass 21. In the following explanation, the model to which the constants in Figure 4(B) are applied to each mechanical element will be referred to as "mechanical model 2 of the finger".

[0029] Furthermore, the constants of each mechanical element are not limited to the example shown in Figure 4(B), and it is possible to obtain a response roughly equivalent to that of a human finger by adopting values ​​within the following ranges. Specifically, the mass 11 should be 0.1 to 1.0 g, the mass 21 1 to 10 g, and the mass 31 1 to 10 g; the elastic stiffness of the elastic body should be 5000 to 9000 N / m for elastic body 12, 5000 to 9000 N / m for elastic body 22, and 1000 to 3000 N / m for elastic body 32; and the mechanical resistance of the viscous body should be 1 to 5 Ns / m for viscous body 13, 0 to 1 Ns / m for viscous body 23, and 1 to 10 Ns / m for viscous body 33.

[0030] [Mechanical coupler configuration] Figure 5 shows an example configuration of a mechanical coupler 100 (calibration device, vibration measuring device) used for measuring an oscillator in the first embodiment, which incorporates a mechanical model of a finger. The mechanical coupler 100 is a device that measures the response of the mechanical model of a finger when a signal is input to the oscillator (haptic device HD). To facilitate understanding of the invention, Figure 5 shows only the housing 50 of the mechanical coupler 100 in cross-section, while schematically illustrating the configurations provided inside and outside it.

[0031] The housing 50 has a bottomed cylindrical shape, for example, with an opening 50a formed at the top. The housing 50 houses the finger mechanical model 2 shown in Figure 4(C), and its lower end, i.e., the third stage viscoelastic body (a structure in which springs 32 and dampers 33 are connected in parallel), is fixed to the floor surface 50b (vibration fixing part), while its upper end, i.e., a part of the mass 11, protrudes from the opening 50a. An acceleration sensor 60 is attached to the side of the mass 31. A measuring instrument 80, located outside the housing 50, is connected to the acceleration sensor 60 and performs various measurements based on its output. In addition, a number of legs 51 are provided on the bottom surface of the housing 50.

[0032] For measurement, the haptic device HD to be measured is placed on the mass 11, and if necessary, it is fixed to the mass 11 with screws, adhesive, etc., or fixed to the mass 11 by pressing down on it with a spring. The haptic device HD is also connected to an oscillator 70 that supplies a signal to it. An amplifier to stabilize the output power from the oscillator 70 and a voltmeter to measure the input voltage to the haptic device HD may be provided between the oscillator 70 and the haptic device HD. In the illustrated example configuration, a mechanical model 2 of a finger (a model to which the constants in Figure 4 (B) are applied, and in which the second stage 20 does not contain a viscous material) is incorporated into the mechanical coupler 100, but it is not limited to this, and for example, a mechanical model 1 of a finger to which different constants are applied may be incorporated.

[0033] [Procedure for measuring the sensitivity of haptic devices] Figure 6 is a flowchart showing an example of the procedure for sensitivity measurement. The sensitivity measurement process measures the sensitivity of the haptic device HD and is executed by the mechanical coupler 100 when the measurement start operation is performed. Here, an example procedure for measuring the voltage sensitivity at 1Hz intervals from 20 to 2000Hz is described. The sensitivity of the acceleration sensor 60 is given by Sa[unit: (m / s²). 2 Assume that ) / V]. The following will explain the procedure using an example.

[0034] Step S1: The transmitter 70 sets the initial frequency f. For measurements between 20 and 2000 Hz, 20 Hz is set as the initial frequency f.

[0035] Step S2: The transmitter 70 provides the haptic device HD under measurement with a sinusoidal signal of a predetermined magnitude reference voltage Vr [unit: V] and frequency f. This causes the haptic device HD to vibrate, and this vibration is transmitted to the finger mechanical model 2.

[0036] Step S3: The measuring instrument 80 measures the output from the acceleration sensor 60, and calculates the acceleration As (=Vs × Sa) [unit: m / s²] from the product of this measured value Vs [unit: V] and the sensitivity Sa of the acceleration sensor 60. 2 Find the answer to ].

[0037] Step S4: Next, the measuring instrument 80 calculates the sensitivity Rt (=As / Vr) of the haptic device HD at frequency f from the ratio of acceleration As to the reference voltage Vr [unit: (m / s²)]. 2 ) / V]

[0038] Steps S5, S6: The oscillator 70 checks whether the frequency f has reached the upper limit of the frequency band to be measured (Step S5). In the case of measurements in the 20-2000Hz range, it is checked whether the frequency f has reached 2000Hz. If the check reveals that the frequency f has not yet reached the upper limit, i.e., the frequency to be measured remains (Step S5: Yes), the oscillator 70 raises the frequency f by a predetermined step (for example, 1Hz) (Step S6), and then returns to Step S2 and repeats the procedure from there. This allows for sensitivity measurement of the frequency f after the step-up.

[0039] On the other hand, if the frequency f has reached its upper limit, that is, if all measurements for the frequency to be measured have been completed (Step S5: No), the transmitter 70 and measuring instrument 80 terminate the sensitivity measurement process. By performing the sensitivity measurement process, measurements at different frequencies are repeatedly performed, and as a result, the frequency of the haptic device HD can be determined.

[0040] As described above, the response of the finger mechanical model 2 when mass 11 is subjected to vibration is equivalent to the response of a human finger. In other words, the response of the finger mechanical model 2 to vibrations caused by the operation of the haptic device HD is roughly equivalent to the response of a human finger to vibrations. Therefore, the mechanical coupler 100 incorporating the finger mechanical model 2 can simulate the output when the haptic device HD is worn on the finger. This makes it possible to measure the sensitivity corresponding to the mechanical impedance (wearing load) of various haptic devices when worn on the finger using the same standard, and to objectively evaluate or compare them. Furthermore, the mechanical coupler 100 makes it possible to inspect the quality and performance of haptic devices without using a human finger.

[0041] The configuration of the mechanical coupler 100 shown in Figure 5 and the example procedure for sensitivity measurement shown in Figure 6 are merely examples and can be modified as appropriate depending on the situation.

[0042] For example, instead of supplying a sine wave signal of a specific frequency f from the transmitter 70 to the haptic device HD, a composite signal consisting of the sum of sine waves of multiple frequencies may be supplied. In such a configuration, by frequency decomposing the output of the acceleration sensor 60 using a Fourier transform or the like, it becomes possible to obtain sensitivity characteristics at multiple frequencies in a single measurement.

[0043] The acceleration sensor 60 may be attached to the side of mass 21 or mass 11 instead of the side of mass 31. Alternatively, instead of attaching the acceleration sensor 60, a force sensor or pressure sensor such as a microphone may be placed between the masses, or between the mass and the vibration-fixing surface. In this case, the force sensor or pressure sensor may be placed above or below the viscoelastic body. In other words, the force sensor or pressure sensor can be inserted at any position between the series-connected mechanical elements between mass 11 and the vibration-fixing surface. For example, the force sensor may be placed between the second viscoelastic body and mass 31, or between mass 31 and the third viscoelastic body. When a force sensor is included, the sensitivity of the haptic device HD measured will be force / voltage [unit: N / V]. Regardless of which sensor is used, by attaching the sensor to a location equivalent to a human receptor, it is possible to obtain an output equivalent to human sensory quantity.

[0044] Alternatively, the output from the transmitter 70 may be current [A] or power [W], etc., instead of voltage, depending on the specifications (driving method) of the haptic device HD. If the output from the transmitter 70 is current, the unit of sensitivity measured using the acceleration sensor 60 is [(m / s²] 2 The unit of sensitivity measured using the force sensor is [N / A]. Also, when the output from the transmitter 70 is taken as power, the unit of sensitivity measured using the acceleration sensor 60 is [(m / s 2 The unit of sensitivity measured using a force sensor is [N / W].

[0045] Furthermore, in the above example procedure, the measurement target frequency band is set to 20-2000 Hz, but instead, the measurement target may be 20-400 Hz, which is commonly used for vibration sensation in human fingers. The frequency increase step is not limited to 1 Hz, and any step can be selected. In addition, in the above example procedure, the measurement proceeds through the mutual cooperation between the transmitter 70 and the measuring instrument 80, but a separate control unit may be provided in the mechanical coupler 100, and the control unit may perform overall control related to the measurement.

[0046] [Mechanical coupler of the second embodiment] Figure 7 shows an example configuration of the mechanical coupler 200 according to the second embodiment. The mechanical coupler 200 of the second embodiment is for measuring the sensitivity of a ring-shaped haptic device HD that is worn on a human finger. In the mechanical coupler 200, the configuration of the housing 150 is particularly different from that of the mechanical coupler 100 of the first embodiment shown in Figure 5.

[0047] The housing 150 has, for example, a diameter of about 10 mm, and one side of it is fixed to a roughly U-shaped rack 151. Similar to the housing 50 in the mechanical coupler 100 of the first embodiment, the housing 150 houses the mechanical finger model 2, and a part of the mass 11 (mechanical finger model 2) (shaded portion in the figure) protrudes from an opening formed in the upper part of the housing 150. Although not shown in the figure, the internal structure of the housing 150 is the same as the internal structure of the housing 50 in the mechanical coupler 100, except for its size.

[0048] The ring-shaped haptic device HD has a housing 150 passed through the inside of the ring, and is positioned so that its inner circumferential surface (vibrating surface) is in contact with the mass 11. It is not fixed with screws or adhesive, but rather fixed by springs 152 and a retaining plate 153 connected to a rack 151, pressing against the mass 11. The haptic device HD is also connected to an oscillator 70 that supplies a signal to it. Sensitivity measurement is then performed. The sensitivity measurement process performed by the mechanical coupler 200 is the same as the sensitivity measurement process described above (Figure 6). The mechanical coupler 200 can also achieve the same effect as the mechanical coupler 100 in the embodiment.

[0049] Alternatively, the haptic device HD may be fixed using rubber or the like instead of the spring 152 and the retaining plate 153, or the fixing device may be omitted if the haptic device HD is fixed (stable) to the mass 11 without being held down. If a spring is used as the fixing device, it is necessary to use a spring that is sufficiently soft in the finger mechanical model 2 system so that the excitation force of the haptic device HD can be transmitted to the finger mechanical model 2 to the maximum extent.

[0050] [Mechanical model of a finger in another embodiment] Figure 8 shows examples of the configuration of mechanical finger models of other embodiments. Of these, (A) is a diagram showing an example of the configuration of mechanical finger model 3 (from top to bottom: plan view, front view, and cross-sectional view along the AA cutting line in the plan view), and (B) is a diagram showing an example of the configuration of mechanical finger model 4 (from top to bottom: plan view, front view, and cross-sectional view along the BB cutting line in the plan view). In order to ensure visibility of the figures, the viscoelastic bodies 15, 25, and 35 in the plan view and front view of Figure 8 are shaded with a dark color. Also, in Figure 8 (A), only one of the four viscoelastic bodies 15, 25, and 35 provided on the same ring is labeled with a reference numeral.

[0051] In the mechanical finger models 1 and 2 shown in Figure 4, three masses and three viscoelastic units were connected alternately in a line. In contrast, in mechanical finger models 3 and 4, mass 11, which corresponds to the point mass on the surface of the finger that the oscillator contacts, forms approximately the center of the entire model, and the three masses and three viscoelastic units are connected alternately in the radial direction of mass 11. If we consider mechanical finger models 3 and 4 as concepts represented by equivalent circuits, then in mechanical models 3 and 4, as in mechanical finger models 1 and 2 described above, the masses and viscoelastic units are connected in series.

[0052] Specifically, in the finger mechanical model 3, as shown in Figure 8(A), a viscoelastic unit consisting of four viscoelastic bodies 15 arranged at approximately equal intervals is connected to the outer surface of a roughly cylindrical mass 11, a roughly annular mass 21 is connected to the outer surface of the four viscoelastic bodies 15, a viscoelastic unit consisting of four viscoelastic bodies 25 arranged at approximately equal intervals is connected to the outer surface of the mass 21, a roughly annular mass 31 is connected to the outer surface of the four viscoelastic bodies 25, a viscoelastic unit consisting of four viscoelastic bodies 35 is connected to the outer surface of the mass 31, and the outer surfaces of the four viscoelastic bodies 35 are fixed to a rigid body RB.

[0053] Furthermore, in the finger mechanical model 4, as shown in Figure 8(B), a viscoelastic unit consisting of a roughly annular viscoelastic body 15 is connected to the outer surface of a roughly cylindrical mass 11, a roughly annular mass 21 is connected to the outer surface of the viscoelastic body 15, a viscoelastic unit consisting of a roughly annular viscoelastic body 25 is connected to the outer surface of the mass 21, a roughly annular mass 31 is connected to the outer surface of the viscoelastic body 25, a viscoelastic unit consisting of a roughly annular viscoelastic body 35 is connected to the outer surface of the mass 31, and the outer surface of the viscoelastic body 35 is fixed to the rigid body RB.

[0054] These finger mechanical models 3 and 4 can achieve the same effects as finger mechanical models 1 and 2 by selecting appropriate characteristic values ​​for each mechanical element. Furthermore, by incorporating either finger mechanical model 3 or 4 into mechanical couplers 100 and 200, the same effects as mechanical couplers 100 and 200 incorporating either finger mechanical model 1 or 2 can be achieved.

[0055] In Figure 8, the thicknesses of masses 11, 21, and 31, and viscoelastic bodies 15, 25, and 35 are shown to be larger than those of rigid body RD in order to facilitate understanding of the structure of finger mechanical models 3 and 4. However, in reality, the thicknesses of masses 11, 21, and 31, and viscoelastic bodies 15, 25, and 35 may be the same as or smaller than those of rigid body RD. In any case, since the haptic device to be measured will be placed on mass 11, mass 11 is made thicker than the other mechanical elements and protrudes more than the other mechanical elements to prevent the haptic device from interfering with them.

[0056] Furthermore, in Figure 8(A), the three viscoelastic units included in the finger mechanical model 3 are each composed of four viscoelastic bodies, but each viscoelastic unit can consist of any number of viscoelastic bodies, and is not limited to four. Also, viscoelastic bodies 15 and 35 are arranged in a nearly straight line when viewed radially, and viscoelastic body 25 is positioned off this line (rotated approximately 45 degrees with respect to the central axis of mass 11), but this arrangement is merely an example, and each viscoelastic body 15, 25, and 35 may be arranged in a different manner. For example, viscoelastic bodies 15, 25, and 35 may be arranged in a nearly straight line when viewed radially.

[0057] [Advantages of the present invention] As described above, the following effects can be obtained with the aforementioned mechanical finger models 1-4 and mechanical couplers 100,200.

[0058] (1) Since the mechanical couplers 100 and 200 incorporate one of the mechanical finger models 1 to 4, which have response characteristics to the vibrations of human fingers, the mechanical couplers 100 and 200 can be used to simulate the sensation of human fingers, and the sensitivity corresponding to the mechanical impedance when various haptic devices are attached to the fingers can be measured.

[0059] (2) By using mechanical couplers 100 and 200, the sensitivity of various haptic devices can be measured using the same standard, making it possible to objectively evaluate the performance of these devices.

[0060] (3) By using mechanical couplers 100 and 200, it is possible to simulate the output when a haptic device is worn on a human finger. This enables device manufacturers to objectively and efficiently perform quality inspections and performance management of haptic devices without using human fingers.

[0061] The present invention can be implemented in various ways without being limited to the embodiments described above.

[0062] In the embodiments described above, the sensitivity of the haptic device is measured using mechanical couplers 100 and 200. However, the measurement target of the mechanical couplers 100 and 200 is not limited to sensitivity. It is possible to measure various responses when a signal is input to the haptic device (for example, output characteristics independent of sensitivity).

[0063] In the embodiments described above, the finger mechanical models 1 to 4 are configured in three stages, but the invention is not limited to this, and any number of stages can be adopted depending on the situation. For example, given that the frequency range commonly used for vibrational sensation in the fingers is 20 to 400 Hz, and that there are dips (anti-resonances) in the mechanical impedance frequency characteristics around 70 Hz and 250 Hz in this range, the finger mechanical model may be configured in two stages to correspond to these two dips (anti-resonances). In such a configuration, it is appropriate to set the frequency range of the measurement target in the sensitivity measurement process to 20 to 400 Hz.

[0064] In the embodiments described above, the mechanical finger models 1 to 4 correspond to human fingers and are configured to simulate the sensation of human fingers. However, a similar configuration can also be used to correspond to human toes.

[0065] Furthermore, the configurations and numerical values ​​mentioned in the explanation of the mechanical finger models 1-4 and mechanical couplers 100 and 200 are merely examples, and it goes without saying that they can be modified as appropriate when implementing the present invention. [Explanation of Symbols]

[0066] Mechanical model of 1, 2, 3, 4 fingers 11,21,31 Mass 12, 22, 32 Springs (elastic bodies) 13,23,33 Damper (viscous material) 50 cabinets 60 Accelerometer 70 Transmitter 80 Measuring Instruments 100,200 Mechanical coupler (vibration measuring device) HD haptic device (device being measured)

Claims

1. It is a mechanical model of a finger that mimics a human finger. Multiple masses, The system comprises viscoelastic body units consisting of one or more viscoelastic bodies with the same mass as the aforementioned, A mechanical model of a finger in which the aforementioned masses and the viscoelastic units are alternately connected, the viscoelastic units forming the ends are fixed to a rigid body, and the mass furthest from the rigid body corresponds to a point mass on the surface of the finger.

2. In the mechanical model of a finger according to claim 1, Each of the viscoelastic materials is A mechanical model of a finger characterized by having a structure in which an elastic body and a viscous body are connected in parallel or in series, or being made of a material having both elastic and viscous properties.

3. In the mechanical model of a finger according to claim 2, It comprises three of the aforementioned masses and three of the aforementioned viscoelastic body units, A mechanical model of a finger, characterized in that a first viscoelastic unit is connected to a first mass corresponding to the point mass, a second mass is connected to the first viscoelastic unit, a second viscoelastic unit is connected to the second mass, a third mass is connected to the second viscoelastic unit, and a third viscoelastic unit is connected to the third mass.

4. In the mechanical model of a finger according to claim 3, A mechanical model of a finger, characterized in that the first mass is 0.1 to 1.0 g, the second mass is 1 to 10 g, the third mass is 1 to 10 g, the elastic stiffness of the viscoelastic units is 5000 to 9000 N / m for the first viscoelastic unit, 5000 to 9000 N / m for the second viscoelastic unit, and 1000 to 3000 N / m for the third viscoelastic unit, and the mechanical resistance of the viscoelastic units is 1 to 5 Ns / m for the first viscoelastic unit, 0 to 1 Ns / m for the second viscoelastic unit, and 1 to 10 Ns / m for the third viscoelastic unit.

5. A vibration measuring device comprising a mechanical finger model according to any one of claims 1 to 4, for measuring the response of the mechanical finger model to vibrations of a device to be measured.

6. In the vibration measuring device according to claim 5, A housing that accommodates the aforementioned mechanical model of the finger, fixes the viscoelastic unit forming the end, and allows a portion of the mass corresponding to the point mass to protrude from the opening, An acceleration sensor attached to the side of any of the aforementioned masses and A vibration measuring device further equipped with [features].

7. In the vibration measuring device according to claim 5, A housing that accommodates the aforementioned mechanical model of the finger, fixes the viscoelastic unit forming the end, and allows a portion of the mass corresponding to the point mass to protrude from the opening, A sensor for detecting force or pressure is inserted at any position between the mass corresponding to the point mass and the portion of the housing to which the viscoelastic body unit forming the end is fixed. A vibration measuring device further equipped with [features].

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