Apparatus and method for testing strength and durability of wearable motion assistance device

Patent metadata

Field	Value
Publication number	US-10871422-B2
Application number	US-201716470100-A
Country	US
Kind code	B2
Filing date	Dec 13, 2017
Priority date	Dec 14, 2016
Publication date	Dec 22, 2020
Grant date	Dec 22, 2020

Abstract

A testing apparatus and testing method capable of efficiently evaluating the strength and durability of a lower-limb-type wearable motion assistance device without being affected by the gravity are implemented. Regarding the testing apparatus for evaluating the strength and durability by repeatedly applying an impact force to the lower-limb-type wearable motion assistance device, when a piston rod is excited at predetermined stroke length and operating speed in a state where a dummy doll wears the wearable motion assistance device, a reciprocable area of a stage relative to an impinging surface of a base is adjusted to make a measured value of a load cell exceed a predetermined reference value.

First claim

The invention claimed is:

1. A testing apparatus for evaluating strength and durability by repeatedly applying an impact force to a lower-limb-type wearable motion assistance device,
the testing apparatus comprising:
a base at one end of which an impinging surface is formed along a vertical direction;
a vibration exciter that is secured at another end of the base and causes reciprocating motion of a piston rod by driving an actuator to excite the piston rod in a horizontal and straight linear direction;
a stage that is connected to a tip of the piston rod and can be moved freely slidably on the base integrally with the piston rod;
a dummy doll that is secured and retained on the stage and partially imitates at least a lower back part and legs of a human body; and
a load cell that is provided on a tip of the piston rod or the impinging surface and measures, via the stage, distortion caused by application of a load on a foot part of the dummy doll,
wherein when the piston rod is excited at predetermined stroke length and operating speed in a state where the dummy doll wears the wearable motion assistance device, a reciprocable area of the stage relative to the impinging surface of the base is adjusted to make a measured value of the load cell exceed a predetermined reference value.

2. The testing apparatus for the wearable motion assistance device according to claim 1 , further comprising:
a monitoring unit that monitors the measured value of the load cell; and
an adjustment unit that automatically adjusts the reciprocable area of the stage relative to the impinging surface of the base on the basis of a monitoring result of the monitoring unit.

3. The testing apparatus for the wearable motion assistance device according to claim 1 ,
wherein the dummy doll has a support to be secured and retained on the stage, a leg guard rod corresponding to a length to the foot part is secured and coupled to one side of the support and a back guard rod corresponding to a length to the lower back part is secured and coupled to another side of the support; and
wherein artificial body imitating parts, each of which imitates the human body, are formed on the leg guard rod and the back guard rod at sites corresponding to a plurality of cuffs provided on the wearable motion assistance device.

4. The testing apparatus for the wearable motion assistance device according to claim 1 ,
wherein the artificial body imitating parts are: artificial foot parts, each of which imitates the foot part of the human body; artificial lower leg parts, each of which imitates a lower leg part; artificial femoral parts, each of which imitates a femoral part; and an artificial lower back part which imitates the lower back part.

5. The testing apparatus for the wearable motion assistance device according to claim 1 ,
wherein each leg guard rod of the dummy doll is inclined relative to, and secured to, the support in such a direction and at such an angle as to imitate a desired resting state in a kinetic chain of the human body during walking; and
wherein an offset flat member is attached to the impinging surface of the base so that only the artificial foot part formed on the leg guard rod inclined relative to the support enters into contact with the offset flat member.

6. The testing apparatus for the wearable motion assistance device according to claim 1 ,
wherein a jig of a predetermined shape that defines an inclination direction and inclination angle of a contact site of each artificial foot part is attached to the impinging surface of the base.

7. The testing apparatus for the wearable motion assistance device according to claim 1 ,
wherein a jig of a predetermined shape that imitates a desired road surface condition is attached to the impinging surface of the base.

8. A testing method for evaluating strength and durability by repeatedly applying an impact force to a lower-limb-type wearable motion assistance device,
wherein the following are included: a base at one end of which an impinging surface is formed along a vertical direction; a vibration exciter that is secured at another end of the base and causes reciprocating motion of a piston rod by driving an actuator to excite the piston rod in a horizontal and straight linear direction; a stage that is connected to a tip of the piston rod and can be moved freely slidably on the base integrally with the piston rod; and a dummy doll that is secured and retained on the stage and partially imitates at least a lower back part and legs of a human body; and
wherein when the piston rod is excited at predetermined stroke length and operating speed in a state where the dummy doll wears the wearable motion assistance device, a reciprocable area of the stage relative to the impinging surface of the base is adjusted to make a measured value of distortion caused by application of a load on a foot part of the dummy doll, which is measured by a load cell provided on a tip of the piston rod or the impinging surface, exceed a predetermined reference value.

9. The testing method for the wearable motion assistance device according to claim 8 ,
wherein the reciprocable area of the stage relative to the impinging surface of the base is automatically adjusted on the basis of a result of monitoring the measured value of the load cell.

10. The testing method for the wearable motion assistance device according to claim 8 ,
wherein the dummy doll has a support to be secured and retained on the stage, a leg guard rod corresponding to a length to the foot part is secured and coupled to one side of the support and a back guard rod corresponding to a length to the lower back part is secured and coupled to another side of the support; and
wherein artificial body imitating parts, each of which imitates the human body, are formed on the leg guard rod and the back guard rod at sites corresponding to a plurality of cuffs provided on the wearable motion assistance device.

11. The testing method for the wearable motion assistance device according to claim 8 ,
wherein the artificial body imitating parts are: artificial foot parts, each of which imitates the foot part of the human body; artificial lower leg parts, each of which imitates a lower leg part; artificial femoral parts, each of which imitates a femoral part; and an artificial lower back part which imitates the lower back part.

12. The testing method for the wearable motion assistance device according to claim 8 ,
wherein each leg guard rod of the dummy doll is inclined relative to, and secured to, the support in such a direction and at such an angle as to imitate a desired resting state in a kinetic chain of the human body during walking; and
wherein an offset flat member is attached to the impinging surface of the base so that only the artificial foot part formed on the leg guard rod inclined relative to the support enters into contact with the offset flat member.

13. The testing method for the wearable motion assistance device according to claim 8 ,
wherein a jig of a predetermined shape that defines an inclination direction and inclination angle of a contact site of each artificial foot part is attached to the impinging surface of the base.

14. The testing method for the wearable motion assistance device according to claim 8 ,
wherein a jig of a predetermined shape that imitates a desired road surface condition is attached to the impinging surface of the base.

Assignees

• Cyberdyne Inc

Inventors

• Nabeshima Kota
• Ogami Kazunori
• Murakami Nobuyoshi

Classifications

• A61H1/024

  Knee (A61H1/0255 takes precedence) · CPC title

• G01M7/08

  Shock-testing · CPC title

• A61B17/1764

  for the knee · CPC title

• A61H1/0262

  Walking movement; Appliances for aiding disabled persons to walk (A61H3/00 takes precedence) · CPC title

• G01N3/30

  by applying a single impulsive force, e.g. by falling weight · CPC title