JP2009136489A - Walking assist device - Google Patents

Abstract

Provided is a walking assistance device that can turn instantly.
A walking assist device 1 includes a frame body 2 having a handle portion 2a, wheels 3a to 3d disposed on both right and left sides of the frame body 2, and an in-wheel motor 4a that rotationally drives each wheel 3a to 3d. To 4d, two left and right controller bars 5a and 5b provided on the handle portion 2a, and a control unit 6. When the controller bar 5a, 5b is rotated or pushed in the reverse direction, the control unit 6 turns the right wheel 3a, 3b and the left wheel 3c, 3d in the reverse direction according to the operated direction. It has ECU which controls in-wheel motor 4a-4d so that it may rotate.
[Selection] Figure 1

Description

  The present invention relates to a handcart type walking assist device capable of turning.

As a conventional wheelbarrow type walking assist device, as described in Patent Document 1, for example, when the handle grip is rotated from a neutral position, the left-hand side corresponds to the amount of electricity corresponding to the amount of rotation. 2. Description of the Related Art There is known one that easily performs a turning operation by causing a difference in rotational speed between a wheel motor and a right wheel motor.
JP-A-4-143172

  However, the above-described wheelbarrow-type walking assist device of the prior art turns while moving forward, so that a certain turning radius is required and the turning cannot be instantaneously performed. For this reason, there is a problem in that it cannot sufficiently cope with a sudden obstacle avoidance or makes the user feel stressed.

  Accordingly, an object of the present invention is to provide a walking assistance device that can turn instantaneously.

  The present invention includes a frame body having a handle portion gripped by a pedestrian, left and right wheels disposed on both sides of the frame body, a plurality of drive portions that respectively rotate and drive each wheel, and left and right wheels provided on the handle portion. One operating unit, a determining unit that determines whether or not the two operating units are operated in opposite directions, and when the determining unit determines that the two operating units are operated in the opposite directions, Control means for controlling each drive unit so as to rotate the left and right wheels in opposite directions according to the operation direction.

  In the walking assistance device according to the present invention, when the two left and right operation units are operated in the opposite directions, each drive is performed so that the left and right wheels are rotated in the reverse direction according to the operation direction of each operation unit. Control part. As a result, the left and right wheels rotate in opposite directions, so that a large turning radius is not required, and it is possible to turn immediately on the spot.

  Preferably, the determination unit determines whether the two operation units have been rotated in opposite directions based on a rotation detection unit that detects a front-rear rotation angle of the two operation units and a detection signal of the rotation detection unit. Means for judging. For example, when the right operation unit is rotated to the front and the left operation unit is rotated to the rear, the right wheel is rotated to the front and the left wheel is rotated to the rear. Turn left instantly on the ground.

  Preferably, the judging means detects whether or not the two operation parts are pushed in opposite directions based on a detection force of the push force detection means and the detection force of the push force detection means. Means for determining whether or not. For example, when the right operation unit is pushed forward and the left operation unit is pushed rearward, the right wheel is rotated forward and the left wheel is rotated rearward. Turn left instantly on the ground.

  According to the walking assistance device of the present invention, it is possible to turn instantaneously. Thereby, for example, it is possible to sufficiently cope with a sudden obstacle avoidance.

  Hereinafter, a preferred embodiment of a walking assistance device according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view showing an appearance of an embodiment of a walking assistance device according to the present invention. In the figure, the walking assist device 1 is an electric wheelbarrow that assists the walking of a pedestrian. The walking assist device 1 includes a frame body 2 having a handle portion 2a, wheels 3a to 3d arranged on the left and right sides of the frame body 2, and in-wheel motors 4a to 4d that independently rotate and drive the wheels 3a to 3d. And left and right controller bars 5 a and 5 b provided on the handle portion 2 a and a control unit 6.

  The frame body 2 includes the handle portion 2a gripped by a pedestrian, a pair of main frames 2b extending from both ends of the handle portion 2a obliquely downward to the front side, and extending obliquely downward to the rear side from a substantially central portion of each main frame 2b. A pair of subframes 2c and a pair of joints 2d that rotatably connect the subframes 2c to the main frames 2b. The wheels (front wheels) 3a and 3c are attached to the lower ends of the main frames 2b, and the wheels (rear wheels) 3b and 3d are attached to the lower ends of the subframes 2c.

  The handle portion 2a is provided at a height that can be gripped by a pedestrian. The handle portion 2a is provided with the two controller bars 5a and 5b for instructing and operating the turning operation of the walking assist device 1.

  The in-wheel motors 4a to 4d are electric motors that generate rotational driving forces for the wheels 3a to 3d, respectively.

  The control unit 6 is suspended from the joint 2d of the frame body 2. An ECU 20 and a power supply unit 21 (see FIG. 2) are provided inside the control unit 6. The control unit 6 also has a luggage compartment for accommodating luggage.

  FIG. 2 is a block diagram showing a control system for controlling the in-wheel motors 4a to 4d. 2, the walking assist device 1 includes a right rotation angle sensor 11a, a left rotation angle sensor 11b, a right push force sensor 12a, a left push force sensor 12b, an ECU (Electronic Control Unit) 20, and a power supply unit 21. And.

  The right rotation angle sensor 11a and the left rotation angle sensor 11b are sensors that respectively detect the front and rear rotation angles of the controller bars 5a and 5b that are rotated (twisted) by a pedestrian. Detection signals (rotation angle signals) from the right rotation angle sensor 11a and the left rotation angle sensor 11b are sent to the ECU 20.

  The right pushing force sensor 12a and the left pushing force sensor 12b are sensors that respectively detect front and back pushing forces of the controller bars 5a and 5b pushed by a pedestrian. Detection signals (pushing force signals) of the right pushing force sensor 12a and the left pushing force sensor 12b are sent to the ECU 20.

  The ECU 20 determines the operation state of the controller bars 5a and 5b based on the rotation angle signals sent from the rotation angle sensors 11a and 11b and the signals sent from the push force sensors 12a and 12b, and according to the determination result. The in-wheel motors 4a to 4d are controlled.

  FIG. 3 is a flowchart showing details of a processing procedure executed by the ECU 20.

  In FIG. 3, first, the rotation angle signals from the rotation angle sensors 11a and 11b and the pressing force signals from the pressing force sensors 12a and 12b are input (step S01). Subsequently, in step S01, it is determined whether or not the controller bars 5a and 5b have been rotated based on the rotation angle signals from the rotation angle sensors 11a and 11b (step S02), and it is determined that the controller bars 5a and 5b have been rotated. If YES, go to step S03. On the other hand, if it is determined that the controller bars 5a and 5b are not rotated, the process proceeds to step S06.

  When it is determined in step S02 that the controller bars 5a and 5b have been rotated, it is determined whether or not the rotation angle signals from the rotation angle sensors 11a and 11b are in opposite phases to each other. It is determined whether or not the rotation direction is the reverse direction (step S03). If it is determined that the rotation direction of the controller bars 5a and 5b is the reverse direction, the process proceeds to step S04. On the other hand, when it is determined that the rotation direction of the controller bars 5a and 5b is not the reverse direction, the process proceeds to step S05.

  When it is determined in step S03 that the rotation directions of the controller bars 5a and 5b are reverse rotation, a rotational torque command value for turning the walking assist device 1 on the spot is obtained, and the process proceeds to step S11 (step S04). . Specifically, a rotational torque command value is determined so that the rotational directions of the right wheels 3a and 3b and the left wheels 3c and 3d are opposite to each other.

  On the other hand, when it is determined in step S03 that the rotation directions of the controller bars 5a and 5b are not reverse rotation, a rotational torque command value for normally turning the walking assist device 1 is obtained, and the process proceeds to step 11 (step S05). . Specifically, rotational torque command values are obtained such that the rotational forces of the right wheels 3a and 3b and the left wheels 3c and 3d are different.

  If it is determined in step S02 that the controller bars 5a and 5b are not rotated, the left / right difference between the front and rear pressing forces of the controller bars 5a and 5b is determined based on the pressing force signals from the pressing force sensors 12a and 12b. Is determined to be greater than or equal to a predetermined force (procedure S06), and if it is determined that the difference between the left and right pushing force is greater than or equal to the predetermined force, the process proceeds to step S07. On the other hand, when it is determined that the left / right difference in the front / rear pushing force is not equal to or greater than the predetermined force, it is determined that the pedestrian does not intend to turn, and the process returns to step S01.

  Subsequently, based on the pressing force signals from the pressing force sensors 12a and 12b, it is determined whether or not the duration of the left-right difference between the front and rear pressing forces of the controller bars 5a and 5b is equal to or longer than a predetermined time (step S07). If it is determined that the left / right difference in the pushing force is maintained for a predetermined time or longer, the process proceeds to step S08. On the other hand, if it is determined that the left / right difference in the front / rear pushing force has not been maintained for a predetermined time or longer, the process returns to step S01 assuming that the pedestrian does not intend to turn.

  Next, by determining whether or not the pressing force signals from the pressing force sensors 12a and 12b are in opposite phases, it is determined whether or not the front and rear pressing directions of the controller bars 5a and 5b are opposite (step S08). If it is determined that the controller bar 5a, 5b is pushed in the opposite direction, a rotational torque command value for turning the walking assist device 1 on the spot is obtained, and the process proceeds to step S11 (step S09). . The rotational torque command value at this time is the same as in step S04.

  On the other hand, when it is determined that the controller bar 5a, 5b is not pushed in the opposite direction, a rotational torque command value for normally rotating the walking assist device 1 is obtained, and the process proceeds to step S11 (step S10). The rotational torque command value at this time is the same as in step S05.

  In step S11, in-wheel motor drive signals corresponding to the respective rotational torque command values obtained are sent to the in-wheel motors 4a to 4d to control the drive of the in-wheel motors 4a to 4d.

  Here, the example in which the walking assistance apparatus 1 turns is shown to FIGS.

  FIG. 4 is a diagram illustrating an example in which the walking assist device 1 normally turns in accordance with the rotational torque command value obtained in step S05. As shown in the figure, when the right controller bar 5a is rotated (twisted) forward and the left controller bar 5b is pushed forward, the right wheels 3a and 3b rotate forward and the left wheel 3c. , 3d rotate to the front side with a rotational torque smaller than that of the right wheels 3a, 3b (the rotational torque may be 0). As a result, the walking assist device 1 turns left. At this time, for example, by increasing the angular velocity when twisting the controller bar 5a, the walking assist device 1 can be turned faster.

  FIG. 5 shows an example in which the walking assist device 1 turns on the spot according to the rotational torque command value obtained in step S04. As shown in the figure, when the right controller bar 5a is rotated (twisted) forward and the left controller bar 5b is rotated (twisted) rearward, the right wheels 3a and 3b rotate forward. The left wheels 3c and 3d rotate rearward. As a result, the walking assist device 1 instantaneously turns left on the spot. At this time, for example, by increasing the angular velocity when twisting the controller bars 5a and 5b, the walking assist device 1 can be turned faster.

  FIG. 6 is a diagram illustrating another example in which the walking assist device 1 turns on the spot according to the rotational torque command value obtained in step S09. As shown in the figure, when the right controller bar 5a is pushed forward and the left controller bar 5b is pushed backward, the right wheels 3a and 3b rotate forward and the left wheel 3c. , 3d rotate rearward. As a result, the walking assist device 1 instantaneously turns left on the spot. At this time, for example, by increasing the pressing force of the controller bars 5a and 5b, the walking assist device 1 can be turned quickly.

  In the above, the in-wheel motors 4a to 4d constitute a plurality of drive units that respectively drive the wheels 3a to 3d to rotate. The controller bars 5a and 5b constitute two left and right operation portions provided on the handle portion 2a. The rotation angle sensors 11a and 11b, the pressing force sensors 12a and 12b, and the procedures S01, S02, S03, and S08 of the EUC 20 are determination means for determining whether or not the two controller bars 5a and 5b are operated in opposite directions. Constitute. In steps S04, S09, and S11 of the ECU 20, when it is determined by the determination means that the two control bars 5a and 5b are operated in opposite directions, the left and right wheels according to the operation directions of the two controller bars 5a and 5b. Control means for controlling the in-wheel motors 4a to 4d is configured to rotate the 3a to 3d in the reverse direction.

  As described above, in the walking assist device 1 of the present embodiment, when the left and right controller bars 5a and 5b provided in the handle portion 2a are rotated or pushed in opposite directions, the operated direction Accordingly, the right wheels 3a and 3b and the left wheels 3c and 3d rotate in opposite directions, so that a large turning radius is not required, and it is possible to instantaneously turn on the spot. As a result, the response to the controller bars 5a and 5b becomes faster, and for example, even if there is a sudden obstacle, it can be quickly avoided. In addition, the stress felt by pedestrians can be reduced.

  In the above-described embodiment, the in-wheel motors 4a to 4d that provide the rotational driving force to all the wheels 3a to 3d are provided. However, the rotational driving force may be applied only to the front wheels, or only the rear wheels rotate. A driving force may be applied.

It is a perspective view which shows the external appearance of a walking assistance apparatus. It is a block diagram which shows the control system of a walking assistance apparatus. It is a flowchart which shows the detail of the process sequence performed by ECU. It is a figure which shows an example of normal turning. It is a figure which shows an example of the spot turning by rotation operation. It is a figure which shows an example of the spot turning by pushing force operation.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Walking assistance apparatus, 2 ... Frame body, 2a ... Handle part, 3a-3d ... Wheel, 4a-4d ... In-wheel motor (drive part), 5a, 5b ... Controller bar (operation part), 11a ... Right rotation angle Sensor (rotation angle detection means, determination means), 11b ... Left rotation angle sensor (rotation angle detection means, determination means), 12a ... Right push force sensor (push force detection means, decision means), 12b ... Left push force sensor ( Pushing force detection means, determination means), 20... ECU (determination means, control means).

Claims (3)

A frame body having a handle portion gripped by a pedestrian;
Left and right wheels arranged on both sides of the frame body;
A plurality of driving units for rotating each of the wheels;
Two left and right operation portions provided on the handle portion;
Determining means for determining whether or not the two operation units are operated in opposite directions;
When it is determined by the determination means that the two operation units are operated in the opposite directions, the driving units are configured to rotate the left and right wheels in the reverse direction according to the operation directions of the two operation units. A walking assist device comprising a control means for controlling the unit.   The determination unit determines whether the two operation units have been rotated in opposite directions based on a rotation detection unit that detects a front-rear rotation angle of the two operation units and a detection signal of the rotation detection unit. The walking assist device according to claim 1, further comprising:   The determination means determines whether or not the two operation parts are pushed in opposite directions based on a detection force of the push force detection means and a detection signal of the push force detection means. The walking assistance device according to claim 1, further comprising:

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