WO2019220794A1

WO2019220794A1 - Vehicle wheel

Info

Publication number: WO2019220794A1
Application number: PCT/JP2019/014203
Authority: WO
Inventors: 克文杉本; 康久神川; 弘樹西條; 一生本郷; 鈴木　裕之; 良寺澤
Original assignee: ソニー株式会社
Priority date: 2018-05-14
Filing date: 2019-03-29
Publication date: 2019-11-21
Also published as: JP2021121510A

Abstract

[Problem] To detect the state of a vehicle wheel and external environment information in an optimum manner. [Solution] The present disclosure provides a vehicle wheel comprising: an inner wheel portion of which rotation is fixed; an outer wheel portion which rotates relative to the inner wheel portion when running; and a detection device for detecting external environment information. With the configuration, it is possible to detect the state of a vehicle wheel and external environment information in an optimum manner.

Description

Wheel

This disclosure relates to wheels.

Conventionally, for example, in Patent Document 1 below, a topographic feature is specified by an in-vehicle ToF camera, a vehicle speed is specified, and a topographic feature and an expected speed of the vehicle when the vehicle reaches the topographic feature are described. Accordingly, it is described that the suspension parameters of the vehicle are automatically adjusted in advance.

Japanese Patent Laying-Open No. 2015-133541

In the conventional system as described in Patent Document 1, a sensor such as a ToF camera is disposed on the vehicle body. This is due to the fact that the body part does not change its posture greatly, and therefore the sensor is arranged at a position where the posture change is small.

However, in such an arrangement, the rotating wheel is reflected on a sensor such as a ToF camera, and it is difficult to detect the state of the wheel. This is because, for example, it is assumed that the information on the movement of the driving part of the wheel becomes noise and affects the recognition of the external environment.

Also, in a mechanical system that moves by wheel driving, when it is assumed that the force generated between the wheel and the ground is measured or the ground contact state is measured, the driving torque of the driving wheel using a general wheel is reduced. In order to measure the external force without being affected, it is desirable to perform measurement at a location closer to the drive wheel than the link to which the drive source is fixed.

Therefore, it was required to optimally detect the external environment information of the wheels.

According to the present disclosure, there is provided a wheel including an inner ring portion whose rotation is fixed, an outer ring portion that rotates with respect to the inner ring portion during traveling, and a detection device that detects external environment information.

As described above, according to the present disclosure, it is possible to optimally detect the external environment information of the wheel.
Note that the above effects are not necessarily limited, and any of the effects shown in the present specification, or other effects that can be grasped from the present specification, together with or in place of the above effects. May be played.

It is a perspective view which shows the whole hubless wheel. It is sectional drawing of a hubless wheel, Comprising: It is a schematic diagram which shows the cross section along the plane which passes along the center of the horizontal width direction of an outer ring | wheel part. FIG. 3 is a cross-sectional view showing a cross section taken along one-dot chain line I-I ′ in FIG. 2. It is a schematic diagram which shows the example which increased the number of sensors with respect to FIG. It is a schematic diagram which shows a mode that it determines that the outer ring | wheel part is contacting the ground. It is a schematic diagram for demonstrating a skid determination. It is a schematic diagram which shows the example which has arrange | positioned the sensor for recognizing an outer ring | wheel part in multiple places. It is a schematic diagram which shows the example which used the sensor for recognizing an outer ring part also as the sensor for external environment recognition. It is a schematic diagram showing a configuration example in which a driving source for operating the outer ring portion and a part of the driving portion of the outer ring portion are included in the recognition range of the sensor. It is a schematic diagram showing a configuration example in which a driving source for operating the outer ring portion and a part of the driving portion of the outer ring portion are included in the recognition range of the sensor.

Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

The description will be made in the following order.
1. Configuration example of hubless wheel 2. Sensor arrangement example 3. Support structure of outer ring part 4. Specific example of detection by a sensor Modified example

1. Configuration Example of Hubless Wheel First, a schematic configuration of a hubless wheel 1000 according to an embodiment of the present disclosure will be described with reference to FIGS. 1 and 2. The hubless wheel 1000 can be widely applied to a moving body including wheels, such as a robot leg structure, a bicycle, and a wheelchair. The hubless wheel 1000 according to the present embodiment has a wide measurable range of the external environment, a wheel mechanism with a high degree of freedom of sensor arrangement, and a wheel capable of measuring the ground contact state of the entire wheel without applying a moment or the like to the measuring unit. It has a structure that achieves the mechanism simultaneously.

FIG. 1 is a perspective view showing the entire hubless wheel 1000. As shown in FIG. 1, the hubless wheel 1000 includes an outer ring portion 100 and an inner ring portion 200 that rotatably holds the outer ring portion 100. As the outer ring portion 100, a pneumatic tire may be used, or an airless tire may be used. Hubless wheel 1000 has an opening at the center of inner ring portion 200. By configuring the wheel as the hubless wheel 1000, an opening can be provided in the inner ring portion 200 whose rotation is fixed. A sensor 300 is provided in the opening. By providing the sensor 300 in the opening, it is possible to acquire various external environmental information such as the road surface condition and the situation in the forward direction of travel.

Thus, in this embodiment, by using the hubless wheel 1000, the sensor is arranged inside the wheel, and the environment is recognized by observing the external environment from the inside of the wheel using the sensor. Further, by measuring the outer ring portion 100 from the inner ring portion 200 using a sensor, information such as the ground contact state of the wheel is acquired. At this time, the hubless wheel 1000 is divided into an outer ring part 100 and an inner ring part 200, and a sensor is provided on the inner ring part 200 whose rotation is fixed, so that external environment information and information such as the grounding state of the outer ring part 100 can be reliably obtained. It is possible to detect.

FIG. 2 is a cross-sectional view of the hubless wheel 1000 and is a schematic view showing a cross section along a plane passing through the center of the outer ring portion 100 in the lateral width direction. As shown in FIG. 2, the hubless wheel 1000 has a structure divided into an outer ring portion 100 and an inner ring portion 200. The inner ring part 200 is provided with a plurality of rotatable support parts (bearings) 210 along the inner periphery of the outer ring part 100. When the hubless wheel 1000 travels on the road surface, when the outer ring portion 100 rotates, the support portion 210 that contacts the inner surface of the outer ring portion 100 rotates. Thereby, the outer ring part 100 rotates with respect to the inner ring part 200 in a state where the outer ring part 100 is supported by the inner ring part 200.

Thus, the outer ring portion 100 is supported by the plurality of support portions 210 and freely rotates, while the inner ring portion 200 does not rotate. Although illustration of components for driving the outer ring portion 100 such as a motor is omitted, it may be mounted on the inner ring portion 200. Moreover, although the support part 210 which supports the outer ring part 100 is fixed to the inner ring part 200, the support part 210 may be fixed to the inner ring part 200 by an elastic body such as a suspension.

2. Sensor Arrangement Example As shown in FIG. 2, a plurality of

sensors

300 and 302 are fixed to the inner ring portion 200. The sensor 300 is a sensor such as an image sensor (camera), a ToF (Time of Flight) sensor, or a distance measuring sensor. Among the plurality of

sensors

300 and 302, the sensor 300 is arranged at a position where an external environment such as the ground surface or the front is taken into view, and observes the external environment. The sensor 302 is disposed at a position where the outer ring portion 100 is put in the field of view, and measures the behavior of the outer ring portion 100. By arranging the

sensors

300 and 302 on the inner ring portion 200, the degree of freedom of arrangement of the

sensors

300 and 302 can be improved, and the sensors can be installed at or near the wheels while suppressing noise and a reduction in the field of view. . As a result, it is possible to widely acquire the state near the wheel regardless of the posture of the vehicle body. Further, since no moment acts on the

sensors

300 and 302, the grounding of the wheel can be accurately detected as will be described later. Further, since no moment acts on the

sensors

300 and 302, it is possible to detect the wheel driving situation and the generated force of the wheels. Moreover, since the

sensors

300 and 302 are hidden in the inner ring portion 200, the degree of freedom in the design surface is also improved.

As described above, the measurement may be performed separately for different purposes by the plurality of

sensors

300 and 302, or may be performed for different purposes by using a single sensor. When a single sensor is also used, only one of the

sensors

300 and 302 shown in FIG. 2 may be measured. The

sensors

300 and 302 may be electrostatic or magnetic sensors.

In a mechanical system that operates by friction with the ground, such as the hubless wheel 1000 according to the present embodiment, the operation depends on the state of contact with the ground, the relative speed, the surface roughness, the slipping state, and the like. This information can be acquired in advance by the

sensors

300 and 302 to improve exercise performance.

3. FIG. 3 is a cross-sectional view showing a cross section taken along one-dot chain line II ′ in FIG. As shown in FIG. 3, a convex portion 212 or a concave portion 214 is provided on the outer peripheral surface of the support portion 210. A concave portion 102 or a convex portion 104 corresponding to the convex portion 212 or the concave portion 214 is provided on the inner peripheral surface of the outer ring portion 100. The convex portion 212 of the support portion 210 is engaged with the concave portion 102 of the outer ring portion 100, or the concave portion 214 of the support portion 210 is engaged with the convex portion 104 of the outer ring portion 100. With such a configuration, the outer ring portion 100 is suppressed from deviating from the support portion 210.

4). Specific Example of Detection by Sensor FIG. 4 is a schematic diagram showing an example in which the number of sensors is increased with respect to FIG. In the example shown in FIG. 4, in addition to the

sensors

300 and 302,

sensors

304, 306 and 308 are further provided in the inner ring portion 200.

As described above, in this embodiment, the external environment is observed and the outer ring portion 100 is measured from the sensor provided in the inner ring portion 200. The external environment is observed using a sensor arranged at a position where the external environment can be measured from the inner ring part 200. In this embodiment, the torus shape realized by the hubless wheel structure is adopted, and the sensors 300 to 308 are arranged in the “hole (opening)” portion of the torus shape, so that the ground surface on both sides of the wheel is single. Or it recognizes simultaneously with several cameras. As the external environment information to be observed, information on the front in the traveling direction and the road surface is assumed. As information ahead of the direction of travel, information about obstacles can be cited. Further, as information on the road surface, the distance to the road surface, the ground surface roughness, the slipping state, and the like can be increased. For this reason, it is desirable that the environment recognition sensor 310 is disposed at a position where the front and the road surface can be recognized. The shape of the inner ring portion 200 is determined so as to realize such an arrangement. In the present embodiment, a torus shape in which an opening is provided in the inner ring portion 200 is illustrated, but the inner ring portion 200 may have a disk shape in which no opening is provided.

Also, when recognizing the external environment, it is desirable that information regarding the driving portion of the outer ring portion 100 is removed as much as possible from information recognized by the sensors 300 to 308. This is because it is assumed that the information on the movement of the driving portion of the outer ring portion 100 becomes noise and affects the recognition of the external environment. In the present embodiment, the sensors 300 to 308 are provided on the inner ring part 200 whose rotation is fixed, and the area of the outer ring part 100 relative to the area recognized by the sensor can be suppressed. It can suppress and can recognize an external environment correctly. When considering that information related to the driving portion of the outer ring portion 100 is excluded from information recognized by the sensors 300 to 308, the sensor provided in the inner ring portion 200 detects external environment information, so that the reflection of the outer ring portion 100 is reflected. Since it is not necessary to provide a separate cover or the like, it can be designed to be lightweight and space-saving. Although it is desirable that the number of sensors is small, the external environment may be recognized by a plurality of sensors.

On the other hand, the measurement of the outer ring part 100 is performed by the sensor 302 arranged at a position where the outer ring part 100 can be measured from the inner ring part 200. FIG. 5 is a schematic diagram showing how the outer ring portion 100 is determined to be in contact with the ground. In FIG. 5, the distance from the inner ring portion 200 to the outer ring portion 100 is measured by the sensor 302 in order to determine that the outer ring portion 100 is in contact with the ground. In the section between the support portions 210 that support the outer ring portion 100, when the outer ring portion 100 contacts the ground, the outer ring portion 100 bends and is reflected in the distance from the sensor 302 to the outer ring portion 100. Grounding determination can be performed by this detection. For example, when the distance from the sensor 302 to the outer ring portion 100 is equal to or smaller than a predetermined threshold value, it is determined that the outer ring portion 100 is in contact with the road surface. Similarly, it can be detected that the outer ring portion 100 has collided with an object on the ground. In addition, the lateral shift of the outer ring portion 100 with respect to the traveling direction can be detected by the sensor 302.

In addition, from the ground contact determination information of the outer ring portion 100 and the external environment information of the hubless wheel 1000 observed as described above, it is possible to measure the state of the wheel with respect to the ground that cannot be measured alone.

For example, as an example of function realization using both the ground contact determination information and the external environment information, there is a wheel slip determination. FIG. 6 is a schematic diagram for explaining the skid determination. As shown in the drawing on the right side of FIG. 6, when the outer ring portion 100 is in contact with the road surface, the relative speed between the outer ring portion 100 and the road surface in the direction perpendicular to the rotation direction of the outer ring portion 100 is determined as long as the outer ring portion 100 does not slip. Is satisfied.

At this time, whether or not the relative speed between the outer ring portion 100 and the road surface in the direction perpendicular to the rotation direction of the outer ring portion 100 calculated by image processing or the like by external environment recognition using a sensor satisfies the constraint condition. The side slip can be determined by using. If the constraint condition is satisfied, no skid has occurred, and if the constraint condition is not met, skid has occurred. As described above, the information by the sensor for observing the surrounding environment and the information by the sensor for measuring the deformation of the outer ring portion can be referred to each other and used for abnormality detection. Further, information from a sensor that observes the surrounding environment may be used to improve the accuracy of the sensor that measures the deformation of the outer ring portion 100, and conversely, the latter may be used to improve the accuracy of the former.

In addition, the figure on the left side of FIG. 6 shows a case where the outer ring portion 100 is moved from the road surface to the left and right in the air. Only with the recognition function of the external environment, the difference between the case where the outer ring portion 100 moves away from the road surface and moves left and right in the air and the side slip cannot be determined. Therefore, a combination of recognition of the external environment and ground contact determination makes it possible to reliably perform the skid determination.

In addition, by using a sensor capable of ranging, such as a ToF sensor or a stereo camera, as a sensor for recognizing the external environment, it is possible to prevent erroneous detection of the ground determination by the sensor 302 described in FIG. By measuring the distance and speed in the vertical direction with respect to the ground surface and the wall surface by the distance measuring sensor, the time when the outer ring portion 100 contacts the ground is predicted. When the distance to the ground surface or wall surface when the outer ring portion 100 is grounded is acquired in advance as a specified value, the distance to the ground surface or wall surface measured by the distance measuring sensor becomes close to the specified value. It can be predicted that the outer ring portion 100 is grounded. Therefore, since the probability that the outer ring portion 100 is grounded is relatively low except in the vicinity of the time at which the grounding is predicted, the detection threshold value of the ground determination by the sensor 302 is raised outside the time at which the grounding is predicted. It is possible to prevent erroneous detection of the ground contact determination.

In addition, information that can be measured both from the observed ground contact determination and the external environment may be used in parallel to detect the abnormality. For example, the amount of deformation of the outer ring portion 100 and the height in the vertical direction estimated from a sensor that recognizes the external environment can be compared to detect an abnormality in the outer ring portion 100 such as puncture or deformation.

5. Modified Example Next, a modified example of the present embodiment will be described. The sensor may be installed not only on the inner ring portion 200 but also on the outside of the hubless wheel 1000 or on a body such as a robot to which the hubless wheel 1000 is attached.

Further, as long as the field of view of the sensor is secured, peripheral devices of the sensor and a control system using the sensor may be incorporated in the inner ring portion 200 of the hubless wheel 1000. Alternatively, the drive source of the outer ring portion 100 may be built in the inner ring portion 200.

Further, the lateral force generated in the outer ring portion 100 can be estimated by observing the lateral distortion of the wheel by a sensor. For example, the lateral force of the outer ring portion 100 can be detected by providing a sensor for measuring strain on the support portion 210. Further, a sensor for measuring distortion may be provided in the inner ring portion 200 and the distortion of the inner ring portion 200 may be measured. Alternatively, a special pattern may be arranged on the outer ring portion 100, and a force such as a lateral force generated in the outer ring portion 100 may be estimated by detecting the shape of the pattern. Further, the vertical load may be estimated from the amount of deformation of the outer ring portion 100 in the vertical direction. An electrostatic or magnetic sensor may be used for behavior observation.

Moreover, as shown in FIG. 7, the measurement of the outer ring portion 100 may be performed by arranging sensors 302 for measuring the outer ring portion 100 at a plurality of locations. Further, as shown in FIG. 8, the sensor 302 for recognizing the outer ring portion 100 may be sufficiently separated from the inner periphery of the outer ring portion 100 and may also be used as an external environment recognition sensor.

Also, a strain sensor or the like may be attached to the inner ring portion 200 or the support portion 210 of the outer ring portion 100, and the behavior measurement of the outer ring portion 100 or behavior measurement assistance may be performed. In the above-described example, the information on the driving part of the outer ring portion 100 is removed from the information obtained by the external environment observation for recognition of the external environment. However, as shown in FIGS. The recognition range may include a drive source for operating the outer ring portion 100 and a part of the drive portion of the outer ring portion 100 to monitor the behavior and abnormality of the outer ring portion 100. 9 and 10, the sensor 310 is provided outside the hubless wheel 1000, and the recognition range of the sensor 310 includes a drive source for operating the outer ring portion 100 and a part of the drive portion of the outer ring portion 100. It is a schematic diagram which shows the example of a structure. In this case, the sensor 310 is installed in a structure that supports the hubless wheel 1000, such as a vehicle body. 9 and 10, the recognition range of the sensor 310 (not shown in FIG. 9) is indicated by a broken line. The recognition range of the sensor 310 includes a driving source for operating the outer ring portion 100 and driving of the outer ring portion 100. Part of the part is included. In this case, it is assumed that the external environment information recognized by the sensor 310 is affected by noise due to the movement of the drive source and the drive part, but the drive source for operating the outer ring part 100 and the drive part of the outer ring part 100 This information can be acquired by the sensor 310. When left and right hubless wheels 1000 are provided as in a vehicle, information on the other of the left and right wheels can be acquired by a sensor 310 provided on one of the left and right wheels.

As described above, according to the present embodiment, the sensor is mounted on the inner ring portion 200 of the hubless wheel 1000, and the state of the outer ring portion 100 and the external environment are recognized by the sensor. Thereby, it is possible to acquire information regarding the state of the outer ring portion 100 and external environmental information.

The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings, but the technical scope of the present disclosure is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field of the present disclosure can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that it belongs to the technical scope of the present disclosure.

In addition, the effects described in this specification are merely illustrative or illustrative, and are not limited. That is, the technology according to the present disclosure can exhibit other effects that are apparent to those skilled in the art from the description of the present specification in addition to or instead of the above effects.

The following configurations also belong to the technical scope of the present disclosure.
(1) an inner ring portion with fixed rotation;
An outer ring that rotates relative to the inner ring during travel;
A detection device for detecting external environment information;
With wheels.
(2) The wheel according to (1), wherein the detection device detects information related to the outer ring portion in addition to the external environment information.
(3) The wheel according to (1) or (2), wherein the detection device is provided in the inner ring portion.
(4) The wheel according to any one of (1) to (3), wherein the detection device detects a state of a road surface on which the outer ring portion contacts the ground as the external environment information.
(5) The wheel according to any one of (1) to (4), wherein the detection device detects a situation ahead in a traveling direction as the external environment information.
(6) A plurality of the detection devices are provided,
The wheel according to (2), wherein at least one detection device detects the external environment information, and at least one other detection device detects information related to the outer ring portion.
(7) The wheel according to (2), wherein the detection device is provided in the inner ring portion and detects information related to the outer ring portion from the inside of the outer ring portion.
(8) The wheel according to (7), wherein the detection device detects a distance to an inner surface of the outer ring portion.
(9) The wheel according to (7) or (8), wherein the detection device detects a lateral shift of the outer ring portion with respect to a traveling direction.
(10) The wheel according to (4), wherein the detection device detects a distance to the road surface.
(11) The wheel according to any one of (1) to (10), wherein the outer ring portion has a ring shape, is provided on an outer periphery of the inner ring portion, and rotates with respect to an outer periphery of the inner ring portion.
(12) When the inner peripheral surface of the outer ring portion moves relative to the outer peripheral surface of the inner ring portion, the outer ring portion rotates with respect to the inner ring portion,
The said inner ring | wheel part is a wheel as described in said (11) which has a some support part which supports the internal peripheral surface of the said outer ring | wheel part.
(13) The wheel according to (12), wherein the support portion rotates with the movement of the inner peripheral surface of the outer ring portion.
(14) The wheel according to any one of (1) to (13), wherein an opening is provided in the inner ring portion, and the detection device is provided at an edge of the opening.

DESCRIPTION OF SYMBOLS 100 Outer ring part 200 Inner ring part 210 Support part 300,302,304,306,308,310 Sensor 1000 Hubless wheel

Claims

An inner ring with fixed rotation,
An outer ring that rotates relative to the inner ring during travel;
A detection device for detecting external environment information;
With wheels.
The wheel according to claim 1, wherein the detection device detects information related to the outer ring portion in addition to the external environment information.
The wheel according to claim 1, wherein the detection device is provided in the inner ring portion.
The wheel according to claim 1, wherein the detection device detects a state of a road surface on which the outer ring portion contacts the ground as the external environment information.
The wheel according to claim 1, wherein the detection device detects a situation ahead of the traveling direction as the external environment information.
A plurality of the detection devices are provided;
The wheel according to claim 2, wherein at least one detection device detects the external environment information, and at least one other detection device detects information related to the outer ring portion.
The wheel according to claim 2, wherein the detection device is provided in the inner ring portion and detects information related to the outer ring portion from the inside of the outer ring portion.
The wheel according to claim 7, wherein the detection device detects a distance to an inner surface of the outer ring portion.
The wheel according to claim 7, wherein the detection device detects a lateral shift of the outer ring portion with respect to a traveling direction.
The wheel according to claim 4, wherein the detection device detects a distance to the road surface.
The wheel according to claim 1, wherein the outer ring portion has a ring shape, is provided on an outer periphery of the inner ring portion, and rotates with respect to an outer periphery of the inner ring portion.
When the inner peripheral surface of the outer ring portion moves relative to the outer peripheral surface of the inner ring portion, the outer ring portion rotates with respect to the inner ring portion,
The wheel according to claim 11, wherein the inner ring portion includes a plurality of support portions that support an inner peripheral surface of the outer ring portion.
The wheel according to claim 12, wherein the support portion rotates with the movement of the inner peripheral surface of the outer ring portion.
The wheel according to claim 1, wherein an opening is provided in the inner ring portion, and the detection device is provided at an edge of the opening.