JP2002078818A - Device for reproducing feel of tread - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device capable of reproducing the feel of a tread such as the hardness or softness or sinking quantity of the tread, the reaction to the sinking, the returning speed of the reaction, or the like. SOLUTION: The load by a body weight in the operation of the tread 5 is detected by a load cell 6, and the displacement quantity according to the load is calculated by use of a spring constant representing the hardness of the tread by a CPU 43 on the basis of the load value. An AC servo motor 31 is driven on the basis of the displacement quantity, and the tread 6 is raised and lowered by a lifting piston 34 through the shaft 33 of a ball screw from a decelerating mechanism 32, whereby the hardness or softness of the tread is imitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for reproducing tactile sensation, and more particularly to a technique for presenting a sense of tactile sensation in a technology for presenting a sense of tactile sensation on a natural ground or a tread made of various materials. The present invention relates to a device that reproduces the feeling of human beings, such as softness or tactile sensation.

[0002]

2. Description of the Related Art Recently, in artificial reality sensation presentation technology, in order to realize a virtual space with higher reproducibility and a sense of reality, a device that stimulates not only sight and hearing but also somatic sensation such as movement and posture. And systems are being developed. As an example, Japanese Patent Application No. Hei 11-2443023 proposes an “irregular walking surface generation device”, and Japanese Patent Application No. Hei 11-155533 proposes a “planar uneven shape forming device”. .

[0003] Furthermore, "skin sensation display using elastic vibration" which simulates the roughness of the surface of an object by vibration (Transactions of the Virtual Reality Society of Japan 2nd Conference (September 1997)) or directly on the sole "Phantom sensation of the sole and its application" (simulated by the Virtual Reality Society of Japan 2nd Conference (September 1997)) that attaches a vibrator and simulates the sense of force with the vibration, "Pin arrangement density and shape discrimination characteristics of a 3D sensory display" that gives a three-dimensional shape of an object by performing a tracing action (Paper Collection of the 2nd Annual Meeting of the Virtual Reality Society of Japan (September 1997) ) Has been announced.

[0004]

However, these published techniques for reproducing tactile sensations are intended to provide an approximate sensation by stimulation of different sensations or to give the shape of an object from the sensation. Hitherto, there has not been proposed a sensor which does not imitate a sensory stimulus and which imitates a tactile sensation felt by a sole when walking.

[0005] Therefore, the main objects of the present invention are the hardness of the tread surface, the softness, the amount of depression, the reaction force against sinking,
It is an object of the present invention to provide a device that can reproduce the feel of a tread, such as the return speed of a reaction force.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a device for reproducing the feeling that a human can feel on a natural ground or a tread made of various materials. Load detecting means for detecting a load when walking,
Control means for controlling the stepping amount of the tread surface in accordance with the detected load.

[0007] Thus, according to the present invention, it is possible to directly simulate the hardness and softness of the tread, and it is possible to simulate the feeling felt by the sole during walking. A highly reproducible virtual walking environment can be realized.

Further, the control means simulates a displacement amount with respect to the sinking of the tread, a sinking speed, a sinking acceleration, a returning speed and an acceleration based on the detection output of the load detecting means.

Further, the control means calculates the amount of displacement according to the load using a spring constant representing the hardness of the tread based on the detection output of the load detection means, and calculates the displacement of the tread based on the calculation result. And an elevating mechanism for performing an elevating operation.

[0010]

FIG. 1 is a diagram showing a basic configuration of the present invention, and FIG. 2 is a diagram showing a basic operation of the same. FIG.
2 and FIG. 2, when the pedestrian 1 steps on or walks on the tread surface 2, a load due to weight is applied to the tread surface 2, and the tread surface 2 is displaced downward by the load and sinks. This displacement is received by the actuator 3, and a reaction force against the sinking is applied from the actuator 3 to the tread surface 2. By detecting the load applied to the tread 2 and controlling the actuator 2 by the control device 4 shown in FIG.
Each element of the feel to the tread 2, the hardness and softness of the surface, the sinking amount, the reaction force to the sinking, the return speed of the reaction force, and the like can be reproduced.

FIG. 3 is a block diagram showing an embodiment of the present invention. In FIG. 3, a load cell 6 for detecting a load is provided below the tread plate 5 as a tread, and a detection output of the load cell 6 is given to the control device 4. The control device 4 includes a preamplifier 41 and an A / D converter 4
2, a CPU 43, and a D / A converter 44. The detection output of the load cell 6 is input to the preamplifier 41, and the load signal of the output of the load cell 6 is amplified and input to the A / D converter 42. The A / D converter 42 converts the load signal into a digital signal and gives the load value to the CPU 43. The CPU 43 calculates the amount of displacement according to the load using a spring constant representing the hardness of the road surface to be simulated, based on a program stored therein, and gives the displacement to the D / A converter 44. The D / A converter 44 converts the displacement into an analog signal and outputs a drive signal to the actuator 3.

The actuator 3 is an AC servomotor 31
, A speed reduction mechanism 32, a shaft 33 of a ball screw, and a lifting piston 34. Then, the AC voltage supplied to the AC servomotor 31 is controlled based on the drive signal from the D / A converter 44, and the rotation speed of the AC servomotor 31 changes. The rotational force of the AC servomotor 31 is reduced by the reduction mechanism 32 to rotate the shaft 33 of the ball screw and move the lifting piston 34 up and down.

FIG. 4 is a diagram for explaining a method of calculating the amount of displacement according to the load using the spring constant by the CPU 43 of FIG.

Referring to FIG. 4, the calculation of the displacement by the CPU 43 of FIG. 3 will be described. The state in which the tread surface is deformed by the load P applied to the tread plate 5 is, as shown in FIG. 4, assumed that a spring 10 supporting the surface is used, and modeling is performed assuming that the amount of displacement varies depending on the spring constant. Can be. Therefore, the hardness of the tread can be defined by the spring constant of the tread. Now, assuming that the displacement when the force P on the tread is applied is δ, the spring constant k is expressed by the following equation (1).

P = k × δ (1) Here, it is assumed that there are two treads having different hardnesses. The spring constant according to the height of these two treads is k
Assuming that 1, k2, the relationship of the following equations (2) and (3) is established as shown in equation (1).

P = k1 × δ1 (2) P = k2 × δ2 (3) Displacement amounts δ1, δ different from equations (2) and (3)
2 will be given. Therefore, by detecting the load applied to the tread by the load cell 6 shown in FIG. 3, the spring constant k corresponding to the hardness of the tread to be simulated is obtained.
Accordingly, the CPU 43 calculates the displacement amount δ caused by the load, and controls the actuator 3 to move the tread plate 5 at a position where the reaction force is properly balanced. Control of the actuator 3 is a technique known as force-position control. By such force-position control, the actuator 3
Is controlled, it is possible to simulate the sinking displacement amount, the sinking speed, the sinking acceleration, the returning speed, and the acceleration of the tread surface of the tread plate 5 according to the amount of stepping.

FIG. 5 is a view showing an example in which the present invention is incorporated in a treadmill. The embodiment shown in FIG. 5 is one in which the present invention is applied to the uneven walking surface generating device described in Japanese Patent Application No. 11-243023 described above.

In FIG. 5, a drive mechanism 12 is provided on one side of the endless belt 11, and a tension mechanism 13 is provided on the other side. Endless belt 11
A plurality of elevating units 14, 14,... A roller 15 that contacts the endless belt 11 is provided above the elevating unit 14.
The actuator 3 is disposed below each of the elevating units 14, and the elevating unit 14 moves up and down by the actuator 3. The specific configuration of the actuator 3 is the same as that of FIG.

Although not shown in FIG. 5, the load cell 6 shown in FIG. 3 is attached to the upper surface of the elevating unit 14, and the load caused by the weight of the pedestrian 1 when walking is detected. As the lifting unit 14 moves up and down, partial unevenness is formed on the flat portion of the belt 11, so that the pedestrian 1 can experience the feeling of running on an uneven surface like a stair or a mountain path, and further step on the endless belt 11. The lifting unit 14 can operate the function of simulating the hardness of the tread 5 by the action of the actuator 3 according to the load at that time.

The tension mechanism 13 is an endless belt 1
When 1 is partially raised and lowered by the lifting unit 14,
The tension generated by absorbing the slack generated in the endless belt 11 is kept constant, that is, the distance between the shafts is kept constant.

The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[0022]

As described above, according to the present invention, the load when a person walks on an artificial tread is detected, and the amount of treading of the tread is controlled in accordance with the detected output. So you can simulate the hardness and softness of the tread,
It is possible to simulate the feeling felt by the sole when walking. Thereby, in the virtual reality presentation technology, a virtual walking environment with higher reproducibility can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of the present invention.

FIG. 2 is a diagram for explaining a basic operation of the present invention.

FIG. 3 is a block diagram showing an overall configuration of an embodiment of the present invention.

4 is a diagram for explaining a method of calculating a displacement amount according to a load using a spring constant by a CPU of FIG. 3;

FIG. 5 is a diagram showing an example in which the present invention is incorporated in a treadmill.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Pedestrian, 2 treads, 3 actuators, 4 control devices, 5 treads, 6 load cells, 10 springs, 11 endless belts, 12 drive mechanisms, 13 tension mechanisms, 14 elevating units, 15 rollers, 31 AC servomotors, 32 reduction mechanisms , 33 Ball screw shaft, 34 Elevating piston, 41 Preamplifier, 42
A / D converter, 43 CPU, 44 D / A converter.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tsutomu Miyazato 2-2-2 Koudai, Seika-cho, Soraku-gun, Kyoto Prefecture Within ATIR Intelligent Video Communications Laboratory (72) Inventor Haruo Noma Soraku-gun, Kyoto 2-2-2, Seikacho Kodai, ATI Inc. Intelligent Video Communications Laboratory

Claims (3)

[Claims] 1. A device that reproduces the feel of a human being on a natural ground or a tread made of various materials, wherein the device is provided on the tread and reduces a load when a human walks on the tread. An apparatus for reproducing the feel of a tread, comprising: a load detecting means for detecting; and a control means for controlling a sinking amount of the tread according to a detection output of the load detecting means. 2. The method according to claim 1, wherein the control unit simulates a displacement amount, a sinking speed, a sinking acceleration, a returning speed, and an acceleration of the tread surface with respect to sinking based on a detection output of the load detecting unit. An apparatus for reproducing the feel of a tread according to claim 1. 3. The calculating means for calculating a displacement amount according to a load using a spring constant representing the hardness of the tread surface based on a detection output of the load detecting means, 2. An elevating mechanism for raising and lowering the tread based on a calculation result.
Or a device for reproducing the feel of the tread as described in 2.