JP2008126936A - Moving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving device having a simple constitution in which the number of wheels for riding over steps constituting a moving mechanism of the moving device is minimized, and capable of riding over oblique steps against the advancing direction, and preventing the shocks and vibrations from being transmitted as much as possible when traveling on an uneven road or riding over steps. <P>SOLUTION: A suspension arm 13 pivotably supports a driven wheel unit 4 by a suspension plate 8 rotatably provided on a body 1a substantially parallel to the body 1a turnably around a supporting shaft 12. A ground contact driven wheel 16 is provided on a driving wheel unit 3 side from the supporting shaft 12 of the suspension arm 13. An auxiliary wheel 14 is provided on the side opposite to the driving wheel unit 3 from the supporting shaft 12. A spring 17 and a damper mechanism 18 are arranged on the ground contact driven wheel 16 side of the suspension arm 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a moving device provided with a moving mechanism driven by a wheel or a crawler that travels outdoors or indoors, and more particularly to a moving device that can stably travel on uneven terrain or climb over a step.

  As mobile devices that can move indoors and outdoors, mobile devices equipped with wheel-type moving mechanisms such as wheelchairs and robots have been developed. The wheel arrangement that constitutes the wheel-type moving mechanism is that the arrangement of two independent driving wheels (driven wheels) and a rotatable free caster (driven wheels) are arranged in front and rear of the wheel-type moving mechanism. It is commonly used because of its height and ability to turn on the spot.

  For example, in a wheel type step-over robot with a moving mechanism, after detecting the step, stop and measure the height or depth, and then determine whether it is possible to get over and step through the stairs continuously. .

  As another mobile robot, a mobile robot having wheels as moving mechanisms on the left and right sides of the main body is known. In this mobile robot, movement by a wheel is assisted by a driven wheel caster fixed to the main body, and surrounding obstacles are detected in a non-contact manner by a detector that emits ultrasonic waves fixed to the upper part of the main body. (See, for example, Patent Document 1).

  This mobile robot measures the distance from the moving floor surface to an obstacle of a certain height or more by the detection unit, and takes an action of avoiding the obstacle by a drive control unit that controls driving of the wheels. For obstacles or steps on the floor, the obstacle passing performance is determined by the radius of the wheel used for the driven wheel caster.

  In addition, as another mobile robot, there are wheels as a moving mechanism on the left and right of the mobile robot main body, and two contact type switch sensors for detecting obstacles are arranged at the front of the main body, so that obstacles can get over Mobile robots that determine whether or not are known. The wheels and the crawler are controlled so that the wheels are used for the movement and the crawler and the moving mechanism are used for the movement according to the determination result of whether or not the boarding is possible (for example, see Patent Document 1).

  In addition, as described above, when trying to get over a step, etc., the traverse performance will be determined by the wheel diameter of the caster placed in front, so as a moving mechanism with countermeasures taken, it is possible to run on uneven terrain and step over ability There is also a mechanism for improving this. (For example, refer to Patent Document 2).

In addition, in an electric wheelchair, when climbing a step, the arm is first operated to lift the front part of the wheelchair body, the front part is placed on the step, and then the telescopic member is extended to lift the rear part of the wheelchair body. In addition, a technique is disclosed in which the entire wheelchair body is placed on the step, and finally the telescopic member is contracted to complete the step movement (see, for example, Patent Document 3).
JP 2006-190105 A JP 2005-125992 A JP 2004-290557 A

  However, in the technique disclosed in Patent Document 1 described above, when overcoming obstacles or steps on the floor surface, the obstacle overcoming performance is determined by the radius of the wheel used for the driven wheel caster.

  In the moving mechanism disclosed in Patent Document 2 described above, the steps must be increased for turning on the spot, separately from forward and backward, and the mechanism is complicated. In addition, there is a problem that shocks and vibrations are transmitted to the main body when traveling on rough terrain and climbing over a step, because the step cannot be over a step oblique to the traveling direction and there is no suspension in the auxiliary wheel portion.

  Further, in the technique disclosed in Patent Document 3 described above, since the operation of the arm is used, a quick operation cannot be performed.

  The present invention has been made in view of these circumstances, and an object of the present invention is to provide a moving apparatus having a simple configuration in which the number of steps for climbing over the steps constituting the moving mechanism of the moving apparatus is as small as possible.

According to one aspect of the present invention, a main body, a driving wheel unit including a driving wheel attached as a moving mechanism to a lower portion of the main body, and a lower portion of the main body at least one of front and rear of the driving wheel unit. A moving device having a driven wheel unit provided,
The driven wheel unit is a suspension plate provided to be rotatable about a suspension plate rotation axis with respect to the main body,
A suspension arm pivotally supported around the fulcrum shaft with respect to the suspension plate;
A grounded follower wheel provided at a position shifted from the suspension plate rotation axis of the suspension arm;
An auxiliary wheel provided closer to the suspension plate rotating shaft than the grounded driven wheel of the suspension arm, and an auxiliary wheel provided to urge the auxiliary wheel in a direction away from the traveling surface, the suspension arm and the suspension plate An elastic body stretched between and
There is provided a moving device comprising a damper mechanism between the suspension arm and the suspension plate.

  ADVANTAGE OF THE INVENTION According to this invention, the number of the wheels for level | step climbing which comprises the moving mechanism of a moving apparatus can be made as simple as possible.

  Hereinafter, a mobile device according to an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same portions are denoted by the same reference numerals, and redundant description is omitted.

(Embodiment 1)
FIG. 1 is a side view showing the configuration in the vicinity of the driven wheel unit of the moving mechanism of the moving device according to the first embodiment.

  The moving device 1 has a moving mechanism 2 formed in the lower part of the main body 1a. The moving mechanism 2 has a drive wheel unit 3 and a driven wheel unit 4. That is, a drive wheel unit 3 as a drive source is provided at the lower part of the main body 1a, and at least one of the front and rear in the traveling direction around the drive wheel unit 3 or a driven wheel unit 4 is provided at the front and rear symmetrical positions. Yes.

  In the drive wheel unit 3, a rotating shaft 7 having a pair of drive wheels 6 fixed thereto is pivotally supported by bearings (not shown) on a support plate 5 that extends downward and is fixed to the lower portion of the main body 1a. The rotating shaft 7 is driven by, for example, a battery-driven motor (not shown). This motor is provided with an encoder (not shown) for measuring the rotation speed and rotation speed, and the movement information about the movement distance and movement direction can be roughly known by the output of the encoder. The mobile device 1 has a touch panel, a keyboard, or wireless communication means as an operation interface (not shown) that can be directly operated by a person. Therefore, based on the movement information, the operation interface can be operated and moved in a desired direction by, for example, dead reckoning (dead reckoning estimated navigation).

  Next, the configuration of the driven wheel unit 4 will be described. A suspension plate 8 is attached to a lower portion of the main body 1a so as to be rotatable about the suspension plate rotation shaft 9 through a suspension plate rotation shaft 9 substantially parallel to the main body 1a. A support portion 11 extending below the suspension plate 8 is provided with a fulcrum shaft 12 in the horizontal direction, and a suspension arm 13 is pivotally supported about the fulcrum shaft 12. The suspension arm 13 has a “heavy” shape, and a top portion 13a (which becomes a fulcrum during rotation) is pivotally supported by a fulcrum shaft 12, and an auxiliary wheel 14 is provided at the front end when traveling in the direction of arrow A. It is attached so that it can rotate freely. On the other hand, a grounded driven wheel 16 that is always in contact with the ground is rotatably attached to the rear end portion when traveling in the direction of arrow A. The auxiliary wheel 14 is provided closer to the suspension plate rotating shaft 9 than the grounded driven wheel 16 of the suspension arm 13. The ground driven wheel 16 is provided at a position shifted from the suspension plate rotating shaft 9 of the suspension arm 13.

  Further, an elastic body, for example, a spring 17 is stretched between the suspension plate 8 and the portion 13 b of the suspension arm 13 that supports the ground driven wheel 16. The spring 17 always urges the suspension arm 13 in a direction in which the auxiliary wheel 14 is separated from the traveling surface 15. Further, a damper mechanism 18 is attached to the portion 13 b of the suspension arm 13 between the suspension plate 8. The damper mechanism 18 relieves shocks and vibrations when the moving device moves. The auxiliary wheel 14 is always in contact with the traveling surface 15 when traveling on flat ground, and is separated from the traveling surface 15 by a predetermined distance h due to the gravity acting on the moving device 1 and the action of the spring 17 and the damper mechanism 18. 15 is configured to float from 15. If the level difference overcoming is 40 to 60 mm, h is preferably set to about half of the level difference, that is, about 20 to 30 mm.

  Next, the step over operation of the moving device 1 having the above-described configuration will be described. FIGS. 2A to 2E are explanatory views of the step over operation by the driven wheel unit 4 having the above-described configuration.

  FIG. 2A shows a state of traveling on a flat ground. In this state, the ground driven wheel 16 is grounded to the traveling surface 15, while the auxiliary wheel 14 is always in non-contact with the traveling surface 15 by the action of the spring 17 and the damper mechanism 18 and only a predetermined distance from the traveling surface 15. It floats away.

  FIG. 2B shows a state where the auxiliary wheel 14 is in contact with the step 20. When the moving device 1 travels and the auxiliary wheel 14 contacts the step 20, the position of the rotation center 14c of the auxiliary wheel 14 is higher than the height of the step 20, so that the position of the rotation center 16c of the ground driven wheel 16 is the same. Even if it is below the height of the step 20, the auxiliary wheel 14 tries to ride on the step 20.

  FIG. 2C shows a state in which the auxiliary wheel 14 has climbed over the step 20. Since the moving device 1 moves forward in the state of FIG. 2B, the suspension arm 13 is pivotally supported by the fulcrum shaft 12, and the auxiliary wheel 14 can ride on the step 20.

  FIG. 2 (d) shows a state where the ground driven wheel 16 is about to climb over the step 20. The auxiliary wheel 14 rides on the step 20, and the force acting on the driven wheel unit 4 with the grounded driven wheel 16 in contact with the step 20 includes the weight P1 from the main body 1a, the grounding force P2 of the grounded driven wheel 16, and the auxiliary wheel. 14 is the contact force P3. Accordingly, from the balance of force, the weight P1 from the main body 1a is distributed to the grounding force P2 of the ground driven wheel 16 and the grounding force P3 of the auxiliary wheel 14. For this reason, the grounded driven wheel 16 is likely to climb on the step 20.

  FIG. 2 (e) shows a state in which the ground driven wheel 16 rides on the step 20. In the state of FIG. 2D, the grounding driven wheel 16 rides on the step 20 as the moving device 1 further moves forward.

  Next, a case where the vehicle travels on a step 20 oblique to the traveling direction will be described. FIG. 3 is a schematic explanatory diagram of a case where a step 20 oblique to the traveling direction is climbed.

  When the moving device 1 travels in the traveling direction indicated by the arrow B, the step 20 is disposed obliquely with respect to the traveling direction. When the moving device 1 moves forward and tries to get over the oblique level difference 20, the grounded driven wheel 16 of the driven wheel unit 4 is always in contact with the traveling surface 15. Therefore, the suspension plate 8 always faces in the traveling direction. As a result, the auxiliary wheel 14 can stably climb on the oblique step 20, and then the ground driven wheel 16 can climb on the step 20. Thereby, in the conventional free rotation caster, the caster does not always remain in the traveling direction at the moment of riding obliquely, and the problem that the movement is unstable can be solved.

  As described above, by using the moving mechanism 2 in the moving device 1 shown in the first embodiment, it is possible to improve overcoming performance of the step 20 without using a motor or a sensor for the driven wheel unit 4 and without complicated control. .

  As a result, in the case of the conventional free rotation caster, the wheel diameter is increased in order to improve the climbing performance of the step 20. However, when the wheel diameter is increased, it is necessary to leave a space for the free-rotating casters to rotate, which eliminates the problem that a large space is required.

  In the moving device 1 shown in the first embodiment, the space where the auxiliary wheels 14 are arranged is originally a space where the rotation free caster moves in a normal structure. Since the auxiliary wheels 14 are arranged in this space, it is not necessary to divide an extra space and the space can be reduced. Further, by attaching the spring 17 and the damper mechanism 18 to the suspension plate 8, vibrations and impacts transmitted from the suspension plate 8 to the main body 1a can be absorbed.

(Embodiment 2)
Next, the moving device 1 according to the second embodiment will be described.

  FIG. 4 is a side view showing a configuration in the vicinity of the driven wheel unit 4 of the moving mechanism 2 of the moving device 1 according to the second embodiment. The moving device 1 according to the second embodiment is different from the moving device 1 according to the first embodiment in that the auxiliary wheel 14 and the ground driven wheel 16 are stretched by a timing belt 21. Other portions are the same as those in the first embodiment.

  That is, as shown in FIG. 4, pulleys 22 and 23 are coaxially attached to the ground driven wheel 16 and the auxiliary wheel 14, respectively. A timing belt 21 is stretched between the two pulleys 22 and 23. Accordingly, when one of the ground driven wheel 16 and the auxiliary wheel 14 rotates, the other rotates in conjunction with the other via the timing belt 21.

  As a result, in the moving device 1 of the second embodiment, in addition to the effects of the moving device 1 of the first embodiment, the ground driven wheel 16 is grounded at the moment when the auxiliary wheel 14 rides on the step 20, so that the rotation Is transmitted to the auxiliary wheel 14. As a result, the performance over the step 20 can be improved. On the other hand, when the grounded driven wheel 16 rides on the step 20, the auxiliary wheel 14 is grounded, so that the rotation of the auxiliary wheel 14 is transmitted to the grounded driven wheel 16 and the climbing performance of the step 20 can be improved. .

(Embodiment 3)
Next, the moving apparatus 1 of Embodiment 3 is demonstrated.

  FIG. 5 is a side view showing a configuration in the vicinity of the driven wheel unit 4 of the moving mechanism 2 of the moving device 1 according to the third embodiment. The moving device 1 of the third embodiment is different in structure from the auxiliary wheel 14 compared to the moving device 1 of the first embodiment. Other portions are the same as those in the first embodiment.

  First, the background state of the third embodiment will be described with reference to the explanatory diagram shown in FIG. That is, for example, when the moving device 1 decelerates suddenly from the moving state, an extra force other than the normal load is applied to the front suspension plate 8 as in P4. At this time, the driven wheel unit 4 is in a state where the auxiliary wheel 14 is also grounded due to the influence of the spring 17.

  In that case, for example, when the center of gravity of the moving device 1 is high, if the vehicle is suddenly decelerated, there is a possibility that the moving device 1 will fall forward, but when the auxiliary wheel 14 comes into contact with the ground, it tends to fall forward. There is an effect to prevent. However, if both the ground driven wheel 16 and the auxiliary wheel 14 are grounded, the suspension plate 8 cannot rotate, and the moving device 1 can only advance in the direction in which the ground driven wheel 16 and the auxiliary wheel 14 are grounded. Thereby, the freedom degree of a moving direction will be restrained.

  As shown in FIG. 6, in the moving apparatus 1 of Embodiment 3, it is comprised as the omnidirectional wheel 24 which provided the roller in the circumferential direction instead of the wheel which can advance the auxiliary wheel 14 only to one direction. Thereby, even when a large load is applied and both the ground driven wheel 16 and the auxiliary wheel 14 are grounded, the auxiliary wheel 14 can move in a desired direction. Thereby, since the suspension board 8 can also rotate, the moving apparatus 1 can move to arbitrary directions.

  In the above-described case, the roller body is provided in an annular shape in the circumferential direction of the auxiliary wheel 14, but a ball may be provided instead of the roller body.

  Therefore, in addition to the effect of the moving device 1 of the first embodiment, the moving device 1 of the third embodiment can cope with the sudden deceleration of the moving device 1.

(Embodiment 4)
Next, the moving apparatus 1 of Embodiment 4 is demonstrated.

  FIG. 7 is an external view of the moving apparatus 1 according to the fourth embodiment, and FIG. 8 is a block diagram showing a control system thereof. The moving device 1 according to the fourth embodiment is configured to have a robot shape in appearance. The basic configuration in which the moving mechanism 2 includes the driving wheel unit 3 and the driven wheel unit 4 is the same as that of the first to third embodiments described above, but the left and right driving wheels 6a and 6b of the driving wheel unit 3 are independently driven. It is a circle. A camera 31 is mounted on the head of the robot, and the direction of the camera 31 is controlled by a camera direction changing unit 32 built in the robot.

  As shown in the block diagram of FIG. 8, the control system 30 is roughly divided into an acceleration / deceleration control unit 35 that controls acceleration / deceleration of the drive wheel unit 3 including a drive wheel as a moving unit, and an image of the camera 31. An image processing subsystem 32, a camera direction changing unit 33 that moves and changes the optical axis direction of the camera 31, and a system control unit 34 that collects each unit.

  The camera 31 is a CCD camera and images the running surface 15 and the step 20. Further, the image processing subsystem 32 compares the captured image data with the data stored in the memory, and calculates the distance to the object by triangulation or the like.

  Next, overcoming the step 20 of the moving device 1 of the fourth embodiment will be described. FIG. 9 is a flowchart of overcoming the step 20 of the moving device 1 according to the fourth embodiment.

  First, the camera 31 is directed toward the ground in front of the traveling surface 15 (step S1).

  Next, the image data captured and captured by the camera 31 is subjected to detection image processing of the step 20 by the image processing subsystem 32 (step S2).

  Next, the step 20 is detected by the step detection process (step S3). In the step detection process, the step 20 that can be overridden is detected by comparing with the data stored in the memory.

  Next, when the level difference 20 is detected by the level difference detection process, the moving unit (the drive wheel unit 3) is accelerated before the level difference 20 by the adjustment side control unit 35. On the other hand, if the step 20 is not detected, the process returns to step S1 (step S4).

  Next, when the moving part (driving wheel unit 3) is accelerated before the step 20 by the adjusting side control part 35 and moves forward, and the front driven wheel unit 4 gets on the step 20, the adjusting side control part. The moving part (driving wheel unit 3) is decelerated by 35 (step S5).

  The moving part (drive wheel unit 3) is moved forward while decelerating to complete the step over the step 20 (step S6).

  As described in the flowchart shown in FIG. 9, in the moving device 1 according to the fourth embodiment, as illustrated in FIGS. 10A to 10C, the movement control unit 35 moves the moving unit. The ability to get over the step 20 is further improved by controlling the acceleration / deceleration of the (drive wheel unit 3).

  That is, as shown in FIG. 10A, the vertical axis L1 and the central axis L2 of the moving device 1 coincide with each other in the normal traveling state. Thereby, the center of gravity of the moving device 1 is substantially in the center.

  When acceleration is performed on the moving device 1, the moving device 1 is tilted backward (the vertical axis L1 and the central axis L2 of the moving device 1 are separated) by the spring 17 of the suspension plate 8 as shown in FIG. The center of gravity is also behind.

  On the other hand, if the mobile device 1 is decelerated reversely, as shown in FIG. 10C, the mobile device 1 tilts forward (the vertical axis L1 and the central axis L2 of the mobile device 1 are tilted at A2). ), And the center of gravity is also in front.

  By using this movement of the center of gravity, the step 20 is overcome. That is, before the step 20, the moving device 1 is accelerated to the state shown in FIG. 10B, and the load applied to the auxiliary wheel 14 is reduced with the center of gravity behind. As a result, the distance from the traveling surface 15 of the auxiliary wheel 14 ahead increases. Thereby, the higher step 20 can be overcome. Once the front auxiliary wheel 14 rides on the step 20, this time, the vehicle is decelerated and the center of gravity is moved forward as much as possible as shown in FIG. Along with this, the distance from the traveling surface 15 of the rear auxiliary wheel 14 increases. This makes it easier for the grounded follower wheel 16 to ride next. As described above, when climbing up the step 20, the speed-up control of the step 20 can be improved by performing deceleration control.

  Therefore, in the moving device 1 of the fourth embodiment, in addition to the effect of the moving device 1 of the first embodiment, the step 31 is confirmed by the camera 31, and the moving unit (the driving wheel unit 3) is added by the adjusting control unit 35. By performing the deceleration control, it is possible to further improve the overcoming ability of the step 20.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

The side view which shows the structure of the vicinity of the driven wheel unit of the moving mechanism of the moving apparatus which concerns on Embodiment 1. FIG. (A)-(b) is explanatory drawing of the level | step difference operation | movement of the driven wheel unit of the moving apparatus of the structure of Embodiment 1. FIG. The model explanatory drawing about the case where the moving apparatus of the structure of Embodiment 1 gets on the diagonal level | step difference with respect to the advancing direction. The side view which shows the structure of the vicinity of the driven wheel unit of the moving mechanism of the moving apparatus which concerns on Embodiment 2. FIG. The side view which shows the structure of the vicinity of the driven wheel unit of the moving mechanism of the moving apparatus which concerns on Embodiment 3. FIG. Explanatory drawing about the state used as the background of Embodiment 3. FIG. FIG. 6 is an external view of a moving device according to a fourth embodiment. FIG. 6 is a block diagram illustrating a system of a mobile device according to a fourth embodiment. 10 is a flowchart for overcoming a step of the moving device according to the fourth embodiment. (A)-(c) is an external view of the movement state of the moving apparatus of Embodiment 4. FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Moving apparatus, 1a ... Main body, 2 ... Moving mechanism, 3 ... Drive wheel unit, 4 ... Driven wheel unit, 5 ... Support plate, 6 ... Drive wheel, 7 ... Rotating shaft, 8 ... Suspension plate, 9 ... Suspension plate Rotating shaft, 12 ... fulcrum shaft, 13 ... suspension arm, 14 ... auxiliary wheel, 15 ... running surface, 16 ... grounded driven wheel, 17 ... spring, 18 ... damper mechanism, 20 ... step, 21 ... timing belt, 22 ... pulley , 23 ... pulley, 24 ... omnidirectional wheel, 31 ... camera, 32 ... image processing system, 33 ... camera direction changing unit, 34 ... system control unit, 35 ... acceleration / deceleration control unit

Claims (6)

A main body, a driving wheel unit having a driving wheel attached as a moving mechanism to the lower part of the main body, and a driven wheel unit provided at the lower part of at least one of the main body in front or rear of the driving wheel unit. A mobile device,
The driven wheel unit is a suspension plate provided to be rotatable about a suspension plate rotation axis with respect to the main body,
A suspension arm pivotally supported around the fulcrum shaft with respect to the suspension plate;
A grounded follower wheel provided at a position shifted from the suspension plate rotation axis of the suspension arm;
An auxiliary wheel provided closer to the suspension plate rotating shaft than the grounded driven wheel of the suspension arm, and an auxiliary wheel provided to urge the auxiliary wheel in a direction away from the traveling surface, the suspension arm and the suspension plate An elastic body stretched between and
A moving device comprising a damper mechanism between the suspension arm and the suspension plate.   The moving device according to claim 1, wherein the auxiliary wheel is separated by approximately half the height of the step over which the moving device gets over the moving plane.   The moving device according to claim 1 or 2, wherein power is transmitted to the auxiliary wheel and the ground driven wheel by belt transmission.   The moving device according to claim 1, wherein the auxiliary wheel is an omnidirectional wheel.   The moving device according to claim 1, wherein an acceleration control device that controls acceleration of the driving wheel is attached to the main body.   6. The apparatus according to claim 1, wherein the main body is provided with a camera that detects a position of a step on the traveling surface and an image processing system that processes image information from the camera. The mobile device described.