Walking assist apparatus

Patent metadata

Field	Value
Publication number	US-9603761-B2
Application number	US-201313949260-A
Country	US
Kind code	B2
Filing date	Jul 24, 2013
Priority date	Feb 23, 2011
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

A walking assist apparatus includes a pair of wheels, at least one first driving unit that drives the pair of wheels, a main body that rotatably supports the pair of wheels, and a grip that is disposed at one end of the main body to be able to be gripped. The walking assist apparatus includes a sensor unit configured to detect an angular change in an inclination angle of the main body in a pitch direction, and a first control unit configured and programmed to control an operation of the at least one first driving unit based on an output of the sensor unit such that the angular change of the main body is zero.

First claim

What is claimed is:

1. A walking assist apparatus comprising:
a pair of wheels;
one rotatable auxiliary wheel or a pair of rotatable auxiliary wheels;
at least one first driving unit that drives the pair of wheels;
a main body that rotatably supports the pair of wheels;
a grip that is disposed at one end of the main body to be able to be gripped by a user while standing up and walking and to assist the user in standing up and walking;
a sensor unit configured to detect an angular change in an inclination angle of the main body in a pitch direction; and
a first control unit configured and programmed to control an operation of the at least one first driving unit based on an output of the sensor unit such that the angular change in the inclination angle of the main body converges to zero; wherein
the grip is turnable in a yaw direction of the main body in order to selectively position the one rotatable auxiliary wheel or pair of rotatable auxiliary wheels between the pair of wheels of the main body and the user, or to position the pair of wheels of the main body between the one rotatable auxiliary wheel or pair of rotatable auxiliary wheels and the user.

2. The walking assist apparatus according to claim 1 , wherein the sensor unit includes at least one of an angular velocity sensor, an inclination sensor, and an angular acceleration sensor.

3. The walking assist apparatus according to claim 1 , wherein the main body includes a support unit connected at a first end thereof to the main body so as to be pivotable in the pitch direction; and
a second end of the support unit is provided with the one rotatable auxiliary wheel or a pair of rotatable auxiliary wheels.

4. The walking assist apparatus according to claim 3 , further comprising:
a second driving unit configured to rotate a connection portion of the support unit or the one rotatable auxiliary wheel or pair of auxiliary wheels; and
a second control unit configured and programmed to control the second driving unit; wherein
the second control unit receives designation of a target angle for an angle between the support unit and the main body; and
the second control unit is programmed to control an operation of the second driving unit based on an output of the sensor unit such that the angle between the support unit and the main body is equal to the target angle.

5. The walking assist apparatus according to claim 4 , wherein the second driving unit is provided in the connection portion of the support unit; and
the second control unit is programmed to determine whether a change in output of the sensor unit exceeds a predetermined threshold, and, if it is determined that the change in output of the sensor unit exceeds the predetermined threshold, the second control unit is programmed to perform delay control to reduce a change in angle between the support unit and the main body.

6. The walking assist apparatus according to claim 4 , wherein the second driving unit is provided in the connection portion of the support unit; and
the second control unit is programmed to determine whether a change in output of the sensor unit or a change in output of an encoder of the second driving unit exceeds a predetermined threshold, and, if it is determined that the change in output of the sensor unit or the change in output of the encoder of the second driving unit does not exceed the predetermined threshold, the second control unit is programmed not to control the second driving unit.

7. The walking assist apparatus according to claim 3 , further comprising:
a first restraining mechanism configured to restrain pivoting of the support unit; and
a detector arranged to detect whether there is an input from the user to the grip; wherein
if the detector detects that there is no input to the grip, the first restraining mechanism stops pivoting of the support unit.

8. The walking assist apparatus according to claim 7 , wherein if the detector determines that there is no change in output of the sensor unit for more than a certain period of time, the detector detects that there is no input to the grip.

9. The walking assist apparatus according to claim 7 , wherein the detector includes a contact sensor provided in the grip.

10. The walking assist apparatus according to claim 7 , wherein when the first restraining mechanism stops pivoting of the support unit, the first control unit is programmed not to control the first driving unit.

11. The walking assist apparatus according to claim 7 , further comprising a second restraining mechanism configured to stop rotation of at least one wheel of the pair of wheels when the first restraining mechanism stops pivoting of the support unit.

12. The walking assist apparatus according to claim 1 , wherein the sensor unit includes a pitch gyro sensor, the at least one first driving unit includes a pitch motor, and the main body includes a pitch encoder.

13. The walking assist apparatus according to claim 12 , wherein the pitch gyro sensor is arranged to detect a pitch angular velocity in a right and left direction or substantially in the right and left direction.

14. The walking assist apparatus according to claim 1 , wherein the main body includes a frame that connects the pair of wheels to the main body.

15. The walking assist apparatus according to claim 1 , wherein the first control unit includes a control board including a driver arranged to drive a pitch motor, an analog-to-digital converter, a digital-to-analog converter, a counter and a controller.

16. The walking assist apparatus according to claim 1 , wherein the first control unit is programmed to use a reaction torque of the pair of wheels to control the angular change of the inclination angle of the main body to converge to zero.

Assignees

• Murata Manufacturing Co

Inventors

• Fukunaga Shigeki
• Suzuki Arata
• Shirato Kenichi

Classifications

• A61G2203/42

  for inclination · CPC title

• A61G5/024

  having particular operating means · CPC title

• A61G5/022 Primary

  acting on wheels, e.g. on tires or hand rims · CPC title

• A61H2003/043

  with a drive mechanism · CPC title

• A61H3/04 Primary

  Wheeled walking aids for patients or disabled persons · CPC title