Walking stick and walking assistance device

Patent metadata

Field	Value
Publication number	US-9986797-B2
Application number	US-201615206424-A
Country	US
Kind code	B2
Filing date	Jul 11, 2016
Priority date	Aug 31, 2015
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A walking stick includes a main part that is stick-like, a sensor that detects at least one of an acceleration of the main part and an angular velocity of the main part, a light emitter that emits light on a ground, a balance evaluator that evaluates a user's walking balance stability based on at least one of the detected acceleration and the detected angular velocity, and an emitting controller that controls a light emitting direction of the light based on a result of the evaluation and an inclination angle of the main part.

First claim

What is claimed is:

1. A walking stick comprising:
a main part that is stick-like;
a sensor that detects at least one of an acceleration of the main part and an angular velocity of the main part;
a light emitter that emits light on a ground;
a ground contact sensor that detects contact, at a tip of the main part, with the ground; and
a controller that includes a balance evaluator and an emitting controller, wherein when the ground contact sensor detects that the tip contacts the ground, the balance evaluator evaluates a walking balance stability of a user based on at least one of the detected acceleration and the detected angular velocity, and the emitting controller controls a light emitting direction of the light based on a result of the evaluated walking balance stability and an inclination angle of the main part.

2. The walking stick according to claim 1 , wherein
the emitting controller continues to emit light from the light emitter at a certain light emitting position on the ground for a certain amount of time, even if the inclination angle of the main part changes.

3. The walking stick according to claim 2 , wherein
the certain amount of time is a time from when the ground contact sensor detects contact of the tip until the ground contact sensor detects the next contact.

4. The walking stick according to claim 1 , wherein
the emitting controller controls the light emitting direction using the inclination angle of the main part and a standard light emitting angle indicating a predetermined light emitting direction with respect to a predetermined inclination angle, and adjusts the standard light emitting angle based on the result of the evaluated walking balance stability.

5. The walking stick according to claim 4 , wherein
provided that α represents the standard light emitting angle when the standard inclination angle is 0 degrees with respect to a vertical direction, and β represents the inclination angle between a lengthwise direction of the main part of the stick and the vertical direction, the emitting controller uses α and β to compute a light emitting angle γ between the lengthwise direction of the main part of the stick and the optical axis of light from the light emitter according to

γ
=

cos

-
1

⁢

1
-

tan
⁢

⁢
α
⁢

⁢
sin
⁢

⁢
β

1
+

tan
2

⁢
α

-

2
⁢

⁢
tan
⁢

⁢
α
⁢

⁢
sin
⁢

⁢
β

and uses the computed light emitting angle γ to control the light emitting direction.

6. The walking stick according to claim 4 , wherein
the emitting controller decreases the standard light emitting angle if an evaluation score that expresses a value of walking balance stability, obtained as a result of the evaluated walking balance stability, is greater than a certain threshold value.

7. The walking stick according to claim 6 , wherein
the emitting controller causes the light emitter to start emitting light if the evaluation score is greater than the certain threshold value.

8. The walking stick according to claim 6 , wherein
the evaluation score is at least one of a timewise variance of the detected acceleration and a timewise variance of the detected angular velocity.

9. The walking stick according to claim 6 , wherein
the balance evaluator additionally detects a fall by the user, and computes an evaluation score of the walking balance stability during a certain period immediately prior to the fall being detected, and
the computed evaluation score is used as the certain threshold value.

10. The walking stick according to claim 4 , wherein
the controller additionally includes
storage for storing a plurality of standard light emitting angle candidates,

the balance evaluator evaluates walking balance stability when light is emitted in accordance with the predetermined plurality of standard light emitting angle candidates, and based on the result of the evaluated walking balance stability when light is emitted, stores one of the multiple standard light emitting angle candidates as the standard light emitting angle in the storage, and
the emitting controller acquires the standard light emitting angle from the storage, and uses the acquired standard light emitting angle to control the light emitting direction.

11. The walking stick according to claim 10 , wherein
the storage stores a plurality of standard light emitting angles corresponding to a plurality of walking conditions,
the balance evaluator uses, when the walking balance stability when light is emitted is evaluated, at least one of the detected acceleration and the detected angular velocity to estimate a walking condition of the user currently walking with the walking stick, and
the emitting controller acquires, from the storage, the standard light emitting angle corresponding to the estimated walking condition, and uses the acquired standard light emitting angle to control the light emitting direction.

12. The walking stick according to claim 1 , wherein
the emitting controller causes the light emitter to emit light when the tip of the main part is contacting the ground.

13. The walking stick according to claim 1 , wherein
the sensor additionally detects the inclination angle of the main part.

14. The walking stick according to claim 1 , wherein
the controller additionally includes
an inclination angle calculator that calculates the inclination angle of the main part, based on at least one of the acceleration and the angular velocity detected by the sensor.

15. A walking assistance device attached to a walking stick, the walking assistance device comprising:
a sensor that detects at least one of an acceleration of the walking stick and an angular velocity

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Sato Yoshikuni
• Nakada Toru

Classifications

• A45B3/04 Primary

  electrical · CPC title

• F21V23/0492

  the sensor detecting a change in orientation, a movement or an acceleration of the lighting device, e.g. a tilt switch · CPC title

• A45B2009/002

  Accessories · CPC title

• F21Y2115/10

  Light-emitting diodes [LED] · CPC title

• A45B3/08

  with measuring or weighing appliances · CPC title