JP6573434B2 - Haptic interface - Google Patents

Description

  The present invention relates to a haptic interface using a variable stiffness functional material.

A magnetic viscoelastic body (Magneto-rheological Elastomer) is a functional material whose apparent stiffness changes according to an external magnetic field, and is proposed in, for example, Patent Document 1.
In recent years, in the field of electronic devices, haptic interface technology for giving a skin sensation feedback signal to a user has been studied.
Therefore, the present inventors have examined whether this magnetic viscoelastic body (MRE) can be used for a haptic interface, and have reached the present invention.

JP 2013-181090 A

  An object of the present invention is to propose a novel haptic interface using an MRE that can change the apparent rigidity according to an external magnetic field.

A haptic interface according to the present invention includes a magnetic viscoelastic body whose apparent stiffness changes according to an external magnetic field, an operation input unit of a device that involves a load of displacement force on the magnetic viscoelastic body, and a magnetic viscoelastic body. Magnetic field control means for varying and controlling the applied amount of the external magnetic field against displacement.
Here, the displacement force applied to the magnetic viscoelastic body may be any one of a shear force, a compressive force, a tensile force, and a torsion force, or a combined force thereof.

In the present invention, various materials can be used as the magnetic viscoelastic body as long as it is a functional material whose apparent rigidity changes according to an external magnetic field.
For example, the magnetic particle composite viscoelastic body described in Patent Document 1 can be used.
Further, not only those obtained by combining magnetic particles such as iron powder with an elastomer such as silicon rubber, but also those obtained by combining with various gel bases can be used.

In the present invention, the operation input means is an input means for a user of various devices to operate the device, and changes the MRE in accordance with the input operation.
For example, various methods such as a lever method such as a joystick and a push method for pressing operation can be given.

In the present invention, the magnetic field control means means a means for generating a magnetic force to be applied to the MRE and controlling the magnetic force for the purpose of changing the apparent rigidity.
For example, an iron core type coil for applying and controlling a current can be cited as an example.

  The haptic interface according to the present invention is a simple and arbitrary setting because it is based on a variable resistance force to an operating force due to a change in the apparent stiffness of the MRE as a skin sensation feedback method to the user of the device.

The test apparatus used for the evaluation of MRE responsiveness is shown. (A) is a perspective view, (b) is a plan view, and (c) is a front view. An example of an MRE responsiveness evaluation system is shown. (A)-(d) shows the graph of the resistance change with respect to an electric current output pattern. An example of the structure of the MRE unit is shown. An example of a compression displacement type operation unit is shown. The 2nd example of a compression displacement type operation unit is shown. An example of a twist displacement type operation unit is shown.

The experimental evaluation using the MRE responsiveness evaluation tester shown in FIG. 1 will be described below.
In the test machine, a coil 14 is wound around an iron core 13a in which an iron core 13a and an iron core 13b are connected in a U-shape, and a plate-like connecting member 15 is sandwiched between magnetic viscoelastic bodies (MRE) 12a and 12b. The both sides of the MRE and the end of the iron core 13b were connected by the iron core 13c.
Thus, when a current is applied to the coil, a magnetic closed circuit is formed in the iron core, and an external magnetic field is applied to the MRE.
The connecting member 15 is linked to the stick 11, and when the stick knob 11a is operated back and forth, the connecting member 15 moves back and forth as indicated by arrows in FIG. 1B, and shear force is applied to the MRE.
The purpose of link connection between the stick 11 and the connecting member 15 is to transmit the forward / backward tilting operation of the stick 11 to the horizontal movement of the connecting member.
In the testing machine shown in FIG. 1, a support portion 16a is provided oppositely from the base member 10, and a pair of sub-frames 15b are formed between the sub-frames so as to be rotatable via a rotation shaft 16. One end of the shaft was fixed by a shaft 15a.
The stick 11 is returned to its original state by a spring 17a.

An evaluation system as shown in FIG. 2 was constructed using the testing machine shown in FIG.
The stick 11 was tilted at a constant speed using a linear actuator or the like while a current was applied to the coil in accordance with a predetermined pattern, and the resistance change at that time was analyzed.
FIGS. 3A to 3D are graphs showing changes in resistance against current output patterns 1 to 4.
(A) In pattern 1, 6 A was energized between 0.2 and 0.3 seconds after the start of tilting of the stick.
(B) The pattern 2 was energized with 6 A for about 0.3 seconds.
(C) Pattern 3 was initially energized with 6 A for 0.1 seconds, then stopped for 0.3 seconds, and energized with 6 A for 0.2 seconds.
(D) Pattern 4 was pulsed three times at 0.1 second intervals.
In any energization pattern, a change in the resistance force appeared in accordance with the pulse, and it was confirmed that MRE can be applied to the haptic interface.

The displacement response of MRE appears not only in shearing force but also in compressive displacement and torsional displacement.
FIG. 4 shows an example manufactured as the MRE unit 20.
Ring-shaped MREs 22 a and 22 b are fixed to the upper and lower portions of the iron core 23 connected to the stick 21.
A coil 24 is disposed around the iron core 23.
Moreover, the outer peripheral part of MRE22a, 22b was connected with 2nd iron core 23a, 23b.
In this embodiment, the housing 25 and the lids 25a and 25b are used to house the inside.
Such an MRE unit 20 has an operation of tilting the stick 21 left and right, back and forth, an operation of pushing the stick 21 downward, and a twisting operation of turning the stick 21 around its axis. The torsional displacement response appeared as a resistance force change.
Application examples of this MRE unit are shown in FIGS.

FIG. 5 shows an example in which a cross-shaped plate body 31a is connected to the lower end of the stick 31, and the MRE units 20 are respectively arranged on the lower surface side of each end portion of the plate body 31a.
The plate body 31a has a spherical joint structure of a spherical base 32 and a spherical body portion 32a provided on the base member 30 so as to be inclined in accordance with the inclination direction of the stick 31.
FIG. 6 is a compression type similar to FIG. 5, but the stick 31 is inclined in the XY axis direction by the slide bases 33 and 34, and the displacement angle is detected by the potentiometer 40. In this example, the vertical displacement at both ends of the working rod 37 is transmitted to the stick 21 of the MRE unit 20 via the shaft 41.
The shaft 41 is connected to the potentiometer 40 via support members 35 and 36.
FIG. 7 shows an example in which the rotation of the shaft 41 is directly connected as the torsional displacement of the stick 21 of the MRE unit 20.

10 Base member 11 Stick 11a Knob 12a MRE
12b MRE
13 Iron core 14 Coil 15 Connecting member 15a Connecting shaft 16 Rotating shaft 20 MRE unit 22a MRE
22b MRE
23 Iron core 24 Coil 25 Housing

Claims (2)

A magnetic viscoelastic body whose apparent stiffness changes according to an external magnetic field;
Operation input means for equipment with load of displacement force on the magnetic viscoelastic body,
Have a, and a magnetic field control means for variably and control the application amount of the external magnetic field against the displacement of the magnetic viscoelastic body,
An iron core is connected to the stick as the operation input means,
A ring-shaped magnetic viscoelastic body is fixed to the upper part and the lower part of the iron core,
As the magnetic field control means, a coil is disposed around the iron core, and an outer peripheral portion of the upper and lower ring-shaped magnetic viscoelastic bodies is connected by a second iron core. Haptic interface.   The haptic interface according to claim 1, wherein the displacement force applied to the magnetic viscoelastic body is any one of a shear force, a compressive force, a tensile force, and a torsion force, or a combined force thereof.