JP5316142B2 - Inverted wheel type moving body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inverted wheel type moving body superior in detecting obstacles and capable of downsizing a device. <P>SOLUTION: The inverted wheel type moving body 10 is an inverted bicycle type electric wheelchair, e.g., on which an occupant rides while sitting on an occupant's seat 2. The moving body 10 includes a thin laser sensor 6 as an obstacle detecting sensor. The thin laser sensor 6 can be installed on a footrest 4, a roll-over preventing lever 5, or a driving wheel 3. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an inverted wheel type moving body, and more particularly to an inverted two-wheel electric wheelchair provided with an obstacle detection sensor.

A coaxial two-wheeled vehicle has been proposed in which movement can be controlled by operating an operation lever or a brake lever while a passenger sits and rides (for example, Patent Document 1). In the traveling control of the coaxial two-wheeled vehicle, control is performed so as to set a target value of the rotational angle and rotational angular velocity for the left and right drive wheels and follow the set target value. At this time, in the coaxial two-wheeled vehicle disclosed in Patent Document 1, the target value is set based on the presence / absence of a detection signal from the obstacle detection sensor as well as the operation state of the operation module such as the operation lever and the brake lever. Yes.
And in the coaxial two-wheeled vehicle concerning patent document 1, the obstruction detection sensor is provided in the front of the housing located under a boarding seat.

JP 2007-203965 A

If the obstacle detection sensor is provided in front of the housing as in the case of the coaxial two-wheeled vehicle disclosed in Patent Document 1, the passenger's leg inevitably gets in the way, and the sensing area (detection region) becomes narrow. At this time, it is also conceivable to place the obstacle detection sensor in a position where a person does not enter the sensing area, for example, a stay or the like so as not to obstruct the passenger. However, when the obstacle detection sensor is arranged at such a position, the obstacle detection sensor protrudes forward from the vehicle body, so that the obstacle detection sensor comes into contact with a surrounding object or a person at the time of traveling operation or turning operation, There is a problem of increased risk.
In particular, in an inverted two-wheeled electric wheelchair, the outer shape of the electric wheelchair is defined in the JIS standard, and thus it is necessary to be within that range. It was difficult to install in the place. This problem is not limited to an inverted two-wheeled electric wheelchair, but also in other moving bodies because of the need to avoid collisions with people and objects during traveling.

  The present invention has been made to solve such a problem, and an object thereof is to provide an inverted wheel type moving body that is excellent in detecting an obstacle and can be downsized.

An inverted wheel type moving body according to the present invention is an inverted wheel type moving body that the passenger rides in a seated state, and a footrest for placing the leg of the passenger, and an obstacle installed on the footrest And a detection sensor.
Here, it is preferable that the said footrest can be incorporated in the chassis of an inverted wheel type moving body.

An inverted wheel type moving body according to another aspect of the present invention is an inverted wheel type moving body that the passenger rides in a seated state, and is provided in front of or behind a drive wheel of the inverted wheel type moving body. A fall prevention bar and an obstacle detection sensor installed on the fall prevention bar are provided.
Here, it is preferable that the obstacle detection sensor is rotatably attached to the fall prevention bar via a link mechanism.

An inverted wheel type moving body according to another aspect of the present invention is an inverted wheel type moving body that the passenger rides in a seated state, and an obstacle detection sensor is provided on a side surface of a drive wheel of the inverted wheel type moving body. It is provided.
Here, the obstacle detection sensor is preferably fixed to a wheel of the drive wheel.

  The obstacle detection sensor may have a detection range from the vicinity of the rotation axis of the drive wheel toward the outer periphery.

  Alternatively, the obstacle detection sensor may be arranged so that the center of the detection range is in the pitch axis direction.

The obstacle detection sensor described above is typically a thin laser sensor.
The above-described inverted wheel type moving body is typically an inverted two-wheeled electric wheelchair.

  INDUSTRIAL APPLICABILITY The present invention can provide an inverted wheel type moving body that is excellent in detecting obstacles and can be downsized.

It is a side view which shows the structure of the inverted wheel type moving body concerning embodiment of invention. It is a perspective view which shows the thin laser sensor used in the inverted wheel type moving body concerning embodiment of invention. It is a top view for demonstrating the detection range of the thin laser sensor with which the inverted wheel type moving body concerning embodiment of invention was equipped. It is a side view which shows the structure of the inverted wheel type moving body concerning embodiment of invention. It is a side view which shows the structure of the inverted wheel type moving body concerning embodiment of invention. It is a side view which shows the structure of the inverted wheel type moving body concerning embodiment of invention. It is a side view which shows the structure of the inverted wheel type moving body concerning embodiment of invention. It is a perspective view for demonstrating the detection range of the thin laser sensor with which the inverted wheel type moving body concerning embodiment of invention was equipped. It is a perspective view for demonstrating the detection range of the thin laser sensor with which the inverted wheel type moving body concerning embodiment of invention was equipped. It is a top view for demonstrating the detection range of the thin laser sensor with which the inverted wheel type moving body concerning embodiment of invention was equipped.

Embodiment 1 of the Invention
The inverted wheel type moving body according to the present embodiment is a coaxial two-wheeled vehicle that moves by inverted pendulum control. The inverted wheel type moving body moves to a predetermined position by driving a wheel that contacts the ground. Furthermore, the inverted state can be maintained by driving the wheel according to the output from the gyro sensor or the like. Further, the moving body moves according to the operation amount operated by the operator while maintaining the inverted state. In the example described below, an example in which the present invention is applied to an inverted two-wheel electric wheelchair (hereinafter simply referred to as “wheelchair”) will be described as an inverted wheel type moving body.

  The structure of the wheelchair 10 concerning this Embodiment is demonstrated using FIG. The wheelchair 10 is an inverted wheel type moving body (running body), and includes a right driving wheel 3 and a left driving wheel 3 arranged coaxially. The wheelchair 10 has a boarding seat 2 on which a passenger boardes. Therefore, the wheelchair 10 is a seated mobility robot that can move while a person is sitting. In addition, the wheelchair 10 can be moved even when a person is not riding. For example, when a user who wants to board is operated remotely, the wheelchair 10 moves to the position of the user. For example, when the user presses a call button or the like, the wheelchair 10 moves to the vicinity of the user. Then, after the wheelchair 10 moves to the front of the user, the user gets on board.

  The boarding seat 2 has a seat and a seat back. Since the seat serves as a seating surface on which the passenger sits, the seat is arranged almost horizontally. The seat back is formed so as to extend obliquely backward, and serves as a backrest portion that supports the back of the passenger.

  A chassis 1 is arranged directly under the boarding seat. A right driving wheel 3 and a left driving wheel 3 are attached to the chassis 1. The chassis 1 supports the right drive wheel 3 and the left drive wheel 3 in a rotatable manner. The right drive wheel 3 and the left drive wheel 3 are wheels (drive wheels) for moving the wheelchair 10. The right drive wheel 3 and the left drive wheel 3 rotate around the axle (rotation axis). That is, the right drive wheel 3 and the left drive wheel 3 are arranged coaxially.

  A motor (not shown) for driving the right driving wheel 3 and the left driving wheel 3 is mounted on the chassis 1. Moreover, since the wheelchair 10 is an inverted wheel type moving body, the vehicle body (upper body part) including the passenger seat 2 and the like tilts around the axle. That is, the vehicle body including the passenger seat 2 and the like is rotatably supported. The vehicle body is an upper body portion that rotates about the axle. In the inverted state, the tilt angle of the vehicle body changes as the right drive wheel 3 and the left drive wheel 3 are driven. The vehicle body is provided with a gyro sensor or the like for measuring an inclination angle.

  A foot step 4 is provided in front of the chassis 1. The passenger gets on the footstep 4 and then sits on the boarding seat 2. The foot step 4 is attached to the lower side of the boarding seat 2. Further, the foot step 4 extends in front of the boarding seat 2. As shown in FIG. 1, both feet of the passenger 80 are placed on the foot step 4.

  Further, a front bar 5a and a rear bar 5b, which are fall prevention bars for preventing the fall, are provided on the bottom surface of the chassis 1. In other words, the front bar 5a disposed on the front side of the axle and the rear bar 5b disposed on the rear side of the axle can prevent the vehicle from falling in the front-rear direction. The front bar 5 a protrudes obliquely downward on the front side of the chassis 1, and the rear bar 5 b projects obliquely downward on the rear side of the chassis 1. Therefore, when the tip is excessively tilted, the tip of the front bar 5a contacts the ground, and when the tip is excessively tilted, the tip of the rear bar 5b contacts the ground.

  The front bar 5a and the rear bar 5b can be rotationally driven. In addition, auxiliary wheels are provided at the front ends of the front bar 5a and the rear bar 5b. In the inverted state, the front bar 5a and the rear bar 5b including the auxiliary wheels are separated from the ground. Further, at the timing when the passenger gets on and off, the front bar 5a and the rear bar 5b including the auxiliary wheels are in contact with the ground.

  Armrests are provided on both sides of the passenger seat 2. Further, an operation module (not shown) is provided on the armrest. The operation module is provided with an operation lever (not shown) and a brake lever (not shown). The operation lever is an operation member for the passenger to adjust the traveling speed and traveling direction of the wheelchair 10. The passenger can adjust the moving speed of the wheelchair 10 by adjusting the operation amount of the operation lever. . Moreover, the passenger can designate the moving direction of the wheelchair 10 by adjusting the operating direction of the operating lever. The wheelchair 10 can move forward, stop, retreat, turn left, turn right, turn left, and turn right according to the operation applied to the operation lever. The wheelchair 10 can be braked when the passenger tilts the brake lever.

  The foot step 4 according to the present embodiment is provided with a thin laser sensor 6 that is an obstacle detection sensor. More specifically, the thin laser sensor 6 is built in the vicinity of the tip of the foot step 4 and is arranged so that a laser is emitted from the thin laser sensor 6 and a laser reflected by an obstacle or the like is incident. Yes.

  Here, the structure of the thin laser sensor 6 is shown in FIG. As shown in FIG. 2, the thin laser sensor 6 has a size of about 10 mm to 30 mm in length, 70 mm to 100 mm in width, and about 50 mm to 80 mm in depth, for example. The thin laser sensor 6 has a weight of about 130 g to 160 g. The thin laser sensor 6 emits a laser beam radially from the front center, and has a measurement range P shown in FIGS.

  The thin laser sensor 6 is also called a laser range finder, and includes a light source for irradiating laser light at a predetermined spread angle with respect to the front, and a light receiving unit for receiving reflected light of the laser light emitted from the light source. It has. Then, object detection (sensing) based on the so-called TOF (Time Of Flight) principle is performed to detect the position of the object reflected by the laser beam based on the angle irradiated with the laser beam and the time required for reflection. Is called. The thin laser sensor 6 can acquire environmental information in the moving direction.

  As shown in FIG. 4, the foot step 4 incorporating the thin laser sensor 6 may include a mechanism that is housed inside the chassis 1. For example, a storage part that is a space in which the foot step 4 is stored is provided in the chassis 1, and a guide for moving the foot step 4 to the storage part is further provided. The foot step 4 may be moved to the storage unit by a driving means such as a motor, or may be moved by the user.

Even when the thin laser sensor 6 is housed inside the chassis 1, the front surface thereof is open, so that it is possible to detect an obstacle and to acquire environmental information in the moving direction. With such a configuration, the number of protrusions can be reduced, and the risk of collision during autonomous movement can be reduced.

  The chassis 1 is equipped with a battery and a control box. The front and rear positions of the battery and the control box change with respect to the axle according to the inclination angle of the vehicle body. A battery and a control box are placed on a base plate provided in the chassis 1.

  The control box includes a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), a communication interface, and the like, and controls various operations of the wheelchair 10. And this control box performs various control according to the control program stored, for example in ROM. The control box is well-known feedback such as robust control, state feedback control, PID control, etc. so that the desired acceleration and target speed are obtained according to the operation in the operation module, and the wheelchair 10 is maintained upside down. The motor is controlled by the control. Thereby, the wheelchair 10 travels while accelerating and decelerating according to the operation in the operation module.

  The control box receives an inclination angle from the gyro sensor, an operation amount from the operation module, a rotation speed of the motor from the encoder, and a detection signal from the thin laser sensor 6. Based on these inputs, the control box outputs a command torque to the motor that drives the right driving wheel 3 and the left driving wheel 3. The control box detects the presence of a stepped portion or an obstacle present on the road surface based on information on the road surface shape detected by the thin laser sensor 6, and creates a travel route that avoids these obstacles. be able to. The control box performs an inverted control calculation based on the operation amount from the operation module and the detection signal from the gyro sensor, and calculates a control target value. Further, the control box calculates a deviation between the current rotation speed of the motor and the target rotation speed according to the control target value. The control box performs feedback control by multiplying this deviation by a predetermined feedback gain. The control box outputs a command value corresponding to the drive torque to the motor via an amplifier or the like. Thereby, the wheelchair 10 moves to the speed and direction according to the operation amount.

  As described above, the inverted wheel type moving body according to the present embodiment detects obstacles and the like over a wide range in front without causing the passenger's legs to get in the way even when the passenger is on the vehicle. can do. In addition, since it is not necessary to provide a special stay for the sensor, the device can be reduced in size, and the obstacle detection sensor does not come into contact with the surrounding object or person during traveling operation or turning operation, thereby improving safety. be able to. Also, the obstacle detection sensor does not get in the way even when a person gets on and off the coaxial two-wheeled vehicle. In particular, the wheelchair according to the present embodiment can be easily accommodated in the outer shape range defined in the JIS standard of the electric wheelchair.

Embodiment 2 of the Invention
As shown in FIG. 5, the inverted wheel type moving body according to the second embodiment is an obstacle detection sensor in each of the front bar 5 a and the rear bar 5 b that are the fall prevention bars for preventing the fall. Thin laser sensors 6a and 6b are provided. More specifically, the thin laser sensors 6a and 6b are fixed to the upper surfaces of the flat front bar 5a and the rear bar 5b.

  The thin laser sensor 6a has a detection range in a diagonally downward front direction. The thin laser sensor 6b has a detection range in the diagonally backward direction. The thin laser sensors 6a and 6b can detect an obstacle, and in this example, can measure the distance to the road surface. For this reason, by analyzing the detection signals of the thin laser sensors 6a and 6b and obtaining the distance information to the road surface, the inclination in the pitch direction of the inverted wheel type moving body can be recognized and fed back to the balance control. Is possible.

Further, since obstacles such as pebbles falling on the road surface can be detected, the inverted wheel type moving body can be stopped or avoided before the collision.
In this example, the thin laser sensors 6a and 6b are provided in the front bar 5a and the rear bar 5b, respectively, but not limited thereto, only one of them may be provided.

  Further, as shown in FIG. 6, thin laser sensors 6a and 6b may be provided at the front ends of the front bar 5a and the rear bar 5b via link mechanisms. At this time, the link mechanism may be provided with a mechanism for rotationally driving so that the thin laser sensors 6a and 6b are always kept horizontal. With such a configuration, the detection range by the thin laser sensors 6a and 6b can be expanded.

Embodiment 3 of the Invention
As shown in FIG. 7, the inverted wheel type moving body according to the third embodiment is provided with a thin laser sensor 6 that is an obstacle detection sensor on the side surfaces of the right drive wheel 3 and the left drive wheel 3. Specifically, the thin laser sensors 6a and 6b are provided on the right driving wheel 3a and the left driving wheel 3b, respectively. As shown in FIG. 8, the thin laser sensors 6a and 6b have a wide detection range from the rotation shafts of the right drive wheel 3a and the left drive wheel 3b toward the outer periphery.

  When the right drive wheel 3a and the left drive wheel 3b rotate, the thin laser sensors 6a and 6b rotate while measuring the distance to the obstacle and the road surface around the rotation axis. Three-dimensional data can be restored based on encoder values indicating the respective rotations of the right drive wheel 3a and the left drive wheel 3b and distance data measured by the thin laser sensors 6a and 6b. Thereby, the three-dimensional obstacle information on the side surface of the inverted wheel type moving body can be recognized, and for example, an object that is not known from the two-dimensional information such as an uphill can be detected.

  As shown in FIG. 9, the laser sensors 6a and 6b may be arranged such that the center of the detection direction (detection range) is the pitch axis direction. Also in this case, it is possible to recognize the three-dimensional obstacle information on the side surface of the inverted wheel type moving body, and it is possible to detect an object that is unknown from the two-dimensional information, such as an uphill.

Other embodiments.
In the above example, the two-wheeled moving body has been described, but the present invention is not limited to this. That is, the present invention can also be applied to an inverted wheel type moving body of one wheel or an inverted wheel type moving body of three or more wheels.

  In the above example, the laser sensor is used as the obstacle detection sensor. However, the present invention is not limited to this, and other sensors may be used. For example, an ultrasonic sensor can be used. The ultrasonic sensor includes an ultrasonic irradiation unit that irradiates ultrasonic waves simultaneously at a predetermined spread angle with respect to the front, and a reception unit that receives reflection of the irradiated ultrasonic waves. And based on the intensity | strength of the received ultrasonic wave, the rough position and shape of the object which exist in the area | region which irradiated the ultrasonic wave are sensed.

1 chassis 2 passenger seat 3 driving wheel 4 foot step 5a front bar 5b rear bar 6 thin laser sensor 10 wheelchair P detection range

Claims (4)

An inverted wheel type moving body that the passenger rides in a sitting state,
A fall prevention bar provided in front of or behind the driving wheel of the inverted wheel type moving body;
An inverted wheel type moving body comprising an obstacle detection sensor installed on the fall prevention bar. The obstacle detection sensor, inverted wheel type moving body according to claim 1, wherein the through the link mechanism is rotatably attached to the anti-tip bar. The inverted wheel type moving body according to claim 1 or 2 , wherein the obstacle detection sensor is a thin laser sensor. The inverted wheel type moving body according to any one of claims 1 to 3, wherein the inverted wheel type moving body is an inverted two-wheel electric wheelchair.

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