JP7437622B2 - traveling device - Google Patents

Description

The present invention relates to a traveling device.

In recent years, mobile robots (traveling devices) have been used in a variety of usage environments and applications to support tasks that were traditionally performed manually, and to perform tasks in environments that humans cannot handle. In such a traveling device, the traveling mechanism is required to have high maneuverability and reliability so that it can cope with poor road conditions and traveling in limited spaces.

In addition, there is a known technology for improving the performance of mobile robots in climbing over steps by attaching an auxiliary mechanism to the mobile robot to allow the robot to climb over steps or stairs while loaded with batteries, sensors, luggage, etc. (For example, Patent Document 1)

However, if a rod-shaped auxiliary mechanism is used, for example, if the rod is long, a very large torque will be required to lift the main body of the traveling device; if the rod is shortened, the torque required for the lifting operation will be small, but It is not possible to secure enough step height to climb over. Therefore, in the conventional method, there has been a problem in that it is difficult to achieve both the height of the step that can be climbed over and the reduction of the torque required to get over the step.

In order to solve the above-mentioned problem, the invention according to claim 1 includes at least two running bodies, a main body that supports the at least two running bodies, and a running assist device connected to the main body. The traveling device includes an auxiliary mechanism that transmits an external force for lifting the traveling body to the main body by rotationally driving it in a grounded state, and the auxiliary mechanism is grounded in an involute curve shape. and a region having a shape that does not touch the ground when the starting point and the ending point of the involute curve shape are connected, and the axis of rotation of the auxiliary mechanism and the grounding point are perpendicular to each other during rotational driving in the grounded state. The traveling device is characterized in that the difference between the maximum distance and the minimum distance is greater than twice the distance in the horizontal direction between the rotating shaft and the grounding point.

According to the present invention, by devising the shape of the auxiliary mechanism, it is possible to achieve both the height of a level difference that can be climbed over and the reduction of the torque required to climb over the level difference.

1 is a diagram illustrating an example of the appearance of a traveling device equipped with a traveling assist device according to an embodiment. FIG. 3 is a diagram for explaining the operation of a traveling device using a traveling assist device. (A) is a diagram for explaining the behavior of a traveling device using a pin joint type auxiliary mechanism, and (B) is a diagram for explaining the behavior of a traveling device using a fixed joint type auxiliary mechanism. It is a diagram. FIG. 3 is a diagram for explaining the behavior of the traveling device using the ratchet type auxiliary mechanism according to the embodiment when it climbs over a step. FIG. 1 is a diagram showing an example of the appearance of a driving assist device according to an embodiment. FIG. 3 is a diagram for explaining a dynamic model of an auxiliary mechanism. It is a figure for demonstrating the shape of the auxiliary mechanism used for behavior comparison. (A) (B) It is a figure which shows the parameter of the shape of the auxiliary mechanism used for behavior comparison. It is a figure which shows the behavior of the traveling device to which the mechanism _c1 was attached. It is a figure which shows the behavior of the traveling device to which the mechanism _c2 was attached. FIG. 6 is a diagram showing the time transition of the values of x _d and y _d normalized by the step height H in the interval [0, T]. FIG. 3 is a diagram showing the locus of the traveling device every 0.2 T seconds in the section [0, T] for each mechanism. FIG. 6 is a diagram showing the maximum value of xd normalized by the step height H for each mechanism. FIG. 6 is a diagram showing a trajectory of the traveling device when the grounding point of the auxiliary mechanism is located ahead of the rotation axis. (A) and (B) are diagrams for explaining the shape of an auxiliary mechanism having an involute curve shape according to the embodiment. FIG. 3 is a diagram for explaining the shape of a conventional rod-shaped auxiliary mechanism. FIG. 3 is a diagram for explaining the shape of a conventional arc-shaped auxiliary mechanism. (A) and (B) are diagrams for explaining the relationship between the shape of the auxiliary mechanism and the step-over height according to the embodiment. (A) (B) It is a figure which shows the example of the shape of the auxiliary mechanism based on embodiment. It is a figure for explaining an example of the suitable shape of the auxiliary mechanism concerning an embodiment. It is a figure for explaining an example of the suitable shape of the auxiliary mechanism concerning an embodiment. FIG. 3 is a diagram for explaining the behavior of the travel assist device according to the embodiment when it climbs over a step. FIG. 3 is a diagram showing another example (part 1) of the configuration of the driving assist device according to the embodiment. It is a figure which shows another example (part 2) of the structure of the driving|running|working assistance device based on embodiment. FIG. 7 is a diagram showing another example (part 3) of the configuration of the driving assist device according to the embodiment. 25 is a diagram illustrating an example of a traveling device including the traveling assist device shown in FIG. 24. FIG.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In addition, in the description of the drawings, the same elements are given the same reference numerals, and overlapping description will be omitted.

●Embodiment●
●Driving Assist Device FIG. 1 is a diagram showing an example of the appearance of a traveling device equipped with a driving assist device according to an embodiment. The traveling device 5 includes a traveling device main body constituted by traveling bodies 50a, 50b and a main body portion 55, and a traveling assist device 1 that assists the traveling of the traveling device main body.

The traveling bodies 50a and 50b are units that serve as moving means for the traveling device 5. Although the running bodies 50a and 50b shown in FIG. 1 have triangular shapes, the shape of the running bodies is not limited to this, and may be circular or elliptical wheels. Note that the number of running bodies is not limited to two, and may be three or more. The main body portion 55 is a support body that supports the traveling bodies 50a, 50b in a movable state.

The driving assist device 1 includes assist mechanisms 10a, 10b and a connecting portion 15.
The auxiliary mechanisms 10a and 10b are members that transmit an upward external force to the traveling device 5 by being rotationally driven in a grounded state. The connecting portion 15 is a member for connecting the driving assist device 1 to the main body portion 55. The traveling assist device 1 assists the traveling device 5 to travel. Details of the configuration of the driving assist device 1 will be described later.

Here, the operation of the traveling device including the traveling assist device will be explained using FIGS. 2 to 4. In addition, in FIGS. 2 to 4, in order to simplify the explanation, the traveling assist device is shown connected to the traveling body via the connecting part, but the other end of the connecting part is equipped with an auxiliary mechanism. It is assumed that there is

As shown in FIG. 2, it is assumed that the connecting portion is connected to the rotating shaft of the traveling body. When an external force is applied from below to the auxiliary mechanism in this state, changes in the behavior of the traveling device due to differences in the connection conditions (constraint conditions) of the traveling auxiliary device will be explained.

First, FIG. 3(A) is a diagram for explaining the behavior of a traveling device using a pin joint type traveling assist device. In the traveling device shown in FIG. 3(A), a connecting portion (travel assist device) is rotatably connected to the traveling body (pin joint type). As shown in FIG. 3(A), in the case of the pin joint type, even if an external force is applied to the travel assist device, only the travel assist device rotates. In this case, the traveling body cannot overcome the step without being lifted up.

Next, FIG. 3(B) is a diagram for explaining the behavior of a traveling device using a fixed joint type traveling assist device. In the traveling device shown in FIG. 3(B), a connecting portion (travel assist device) is fixedly connected to the traveling body (fix joint method). As shown in FIG. 3(B), in the case of the fix joint method, the traveling body can be lifted, but the traveling body gets caught on the wall of the step and cannot get over the step.

FIG. 4 is a diagram for explaining the behavior of the traveling device using the ratchet-type traveling assist device according to the embodiment when it climbs over a step. The traveling device shown in FIG. 4 is of a ratchet joint type (ratchet type) in which a connecting portion (travel assist device) is rotatably connected to the traveling body in only one direction. A ratchet is a mechanism used to limit the direction of movement to one direction. As shown in the left diagram of FIG. 4, in the case of the ratchet joint type, the travel assist device uses the weight of the traveling body to lift the center of gravity while remaining horizontal to the ground. Furthermore, as shown in the right figure of Fig. 4, after the traveling body comes into contact with the wall of the step, it is possible to rotate around the corner of the step and climb the wall. can overcome.

In this way, the performance of the vehicle over a step can be changed by changes in behavior due to differences in the connection conditions of the travel assist device. Therefore, the traveling device 5 connects the traveling assist device 1 using a ratchet joint method (ratchet method). The traveling device 5 can improve the performance of getting over a step by rotating the auxiliary mechanisms 10a, 10b and transmitting the driving force in one direction to the traveling device 5.

● Driving aid device ○ External view ○
Next, the configuration of the driving assist device will be explained using FIGS. 5 to 23. FIG. 5 is a diagram showing an example of the appearance of the driving assist device according to the embodiment. The travel assist device 1 is configured by the assist mechanisms 10a, 10b and the connecting portion 15 as described above. The connecting portion 15 includes an actuator 17 for rotationally driving the auxiliary mechanisms 10a and 10b. The traveling assist device 1 assists the traveling of the traveling device 5 by being connected to the main body portion 55 of the traveling device 5 through the connecting portion 15 .

○Simulation○
○Dynamic Model Next, the shapes of the auxiliary mechanisms 10a and 10b included in the travel auxiliary device 1 will be explained using FIGS. 6 to 22. First, with reference to FIGS. 6 to 14, a simulation of the behavior of the traveling device due to the difference in shape of the auxiliary mechanisms will be described in order to examine the shapes of the auxiliary mechanisms 10a and 10b.

FIG. 6 is a diagram for explaining a dynamic model of the auxiliary mechanism. As shown in FIG. 6, the case where the auxiliary mechanism has a rotational axis at point O and has a geometric shape with an arbitrary curve in a part will be considered. The curved portion of the geometric shape shown in FIG. 6 existing on the xy plane can be expressed as shown in the following (Equation 1) when the parameter is t.

It is assumed that the curved portion of the geometric shape that can be expressed by (Equation 1) continues to be in contact with the ground when rotated by an arbitrary angle θ that satisfies [0, θ _lim,c ] on the xy plane. At this time, if the horizontal distance between the axis of rotation and the point of contact when the ground is rotated by θ is x _d , and the vertical distance between the axis of rotation and the point of contact is y _d , then (Formula 1) is converted to the following (Formula 1). 2) can be expressed as follows.

Furthermore, in order for the curved portion to be in contact with the ground, (Formula 2) needs to satisfy the following (Formula 3). Then, by substituting (Formula 2) into (Formula 3), it is expressed as (Formula 4) below. As a result, (Formula 2) is rewritten as (Formula 5a) and (Formula 5b) below.

In this way, by setting arbitrary x _d or y _d using (Equation 5a) and (Equation 5b), it is possible to create a geometric shape that satisfies them for the angle θ.

Simulation method Next, a simulation method for the behavior of a traveling device using auxiliary mechanisms of different shapes will be described using FIGS. 7 and 8. FIG. 7 is a diagram for explaining the shape of the auxiliary mechanism used for behavior comparison.

As shown in FIG. 7, in this embodiment, the behavior was compared using four types of auxiliary mechanisms. The mechanism a has a bar shape, the mechanism b has an arc shape, and the mechanisms c1 and c2 have an involute curve shape. In these mechanisms shown in FIG. 7, in order to satisfy the definition of a Jordan closed curve, the start and end points of the section in contact with the ground are connected by a straight line to the axis of rotation. Moreover, the black dots of each mechanism shown in FIG. 7 indicate the rotation axis of the auxiliary mechanism, and the white dots indicate the contact points with the ground.

Mechanism a, mechanism b, and mechanism c ₁ have three configurations: "y _d = 0 when θ = 0°", "the angular range of θ is 0° to 90°", and "θ = 90°" in order to compare the performance by shape. The parameters l, r, and _a1 were determined so as to satisfy the following three conditions: y _d =H. Furthermore, for the mechanism c1, by substituting x _d =a, y _d =aθ into (Formula 2), the following (Formula 6a) and (Formula 6b) are obtained, which correspond to the parametric variable representation of an involute curve. An involute curve is a plane curve whose normal line is always tangent to a fixed circle.

Furthermore, unlike mechanisms a and b, mechanism _c1 does not have a periodic function in _yd , and therefore is not limited in its range of motion by the fundamental period. Therefore, regarding the involute curve shape, in order to compare with mechanism a and mechanism b, mechanism _c1 has a range of motion in the interval [0, π/2], and a mechanism has a maximum range of motion without interfering with the ground. _c2 were prepared and simulations were conducted for each. For mechanism _c2 , if the maximum value of θ that does not cause interference with the ground is θ _lim , then the next largest solution after 0 in (Equation 7), which is obtained by substituting y _d = a ₁ θ into (Equation 2), is θ _lim . When θ _lim is determined using Newton's method, θ _lim is approximately 4.49. At this time, a ₂ is determined so as to satisfy "y _d (θ _lim )=a ₂ θ _lim =H". Regarding these four shapes, the variables l, r, a ₁ , and a ₂ are determined using the step height H as shown in FIG. 8(A).

Next, the locus of the traveling device in the auxiliary mechanisms having the shapes of mechanism a, mechanism b, mechanism c ₁ and mechanism c ₂ will be explained. First, the auxiliary mechanism is given a constant angular velocity input that satisfies the following (Equation 8) with point B as the rotation axis. On the other hand, the angle θ between the auxiliary mechanism and the ground is determined not only by the angle θ ₂ between the traveling device body and the auxiliary mechanism, but also by the angle θ ₁ between the traveling device body and the ground. to be influenced. The trajectory of θ ₁ cannot be uniquely determined because it is affected by the driving force of the actuator of the traveling device main body and the friction of the wall surface. Therefore, in this simulation, in order to evaluate the shape of the auxiliary mechanism, the following situation was set regarding the trajectory of the traveling device main body, and the trajectory of the entire traveling device was determined. At this time, when the initial angle of θ ₂ is α, the final angle is β, and the angular velocity is ω, the simulation time T can be expressed as shown below (Equation 9).

The specific simulation conditions are as follows. In the initial state, the traveling device is horizontal to the ground and in contact with a wall surface, and a trajectory is considered in which the traveling device body always ascends while being kept horizontal to the ground. At this time, since θ ₁ is always 0, the value of θ is determined only by θ ₂ . Further, α=0. FIG. 8(B) shows properties of the traveling device and surrounding environment used in the simulation. In this simulation, in order to compare the shapes of the auxiliary mechanisms, the shape of the traveling device was simplified and the wheel radius was set to R=0.

○Simulation Results Next, the results of a step-crossing simulation performed on the mechanism shown above will be explained using FIGS. 9 to 14. FIG. 9 is a diagram showing the behavior of the traveling device to which the mechanism c ₁ is attached, and FIG. 10 is a diagram showing the behavior of the traveling device to which the mechanism c ₂ is attached. In FIGS. 9 and 10, the axis of rotation of the auxiliary mechanism is shown by a black circle, and the contact point between the auxiliary mechanism and the ground is shown by a white circle. As shown in FIGS. 9 and 10, mechanism c ₁ and mechanism c ₂ rotate with time, but it can be seen that the positions of the rotation axis and the contact point in the X-axis direction do not change. .

FIG. 11 is a diagram showing the time transition of the values of x _d and y _d normalized by the step height H in the interval [0, T]. Further, FIG. 12 is a diagram showing the locus of the traveling device every 0.2 T seconds in the section [0, T] for each mechanism. In the rod-shaped mechanism a, the horizontal distance x _d between the rotation axis of the auxiliary mechanism and the ground contact point of the auxiliary mechanism is the largest in the initial attitude, and monotonically decreases until x _d =0 at time T. In the arc-shaped mechanism b, the horizontal distance between the axis of rotation of the auxiliary mechanism and the ground is small at and near T=0, but x _d gradually increases, and x _d becomes the largest at time T seconds. In the involute curve-shaped mechanisms c ₁ and c ₂ , x _d is always constant from the initial posture to time T. This shows that the required torque is constant when the frictional force between the auxiliary mechanism and the ground is not considered. Further, since the mechanism c ₁ and the mechanism c ₂ always have a constant dy _d /dθ, controllability is good when combined with a traveling device.

Further, as shown in FIG. 12, when the height of the step that can be climbed over is 20 cm, the maximum distance in the horizontal direction between the rotation axis and the contact point of the rod-shaped mechanism a and the arc-shaped mechanism b is: It will be 20cm. On the other hand, the maximum distance in the horizontal direction between the rotation axis and the contact point of the involute curve-shaped mechanisms c ₁ and c ₂ is smaller than 20 cm. In particular, the maximum horizontal distance between the rotation axis and the contact point of mechanism c ₂ is approximately 4.2 cm, and mechanism c ₂ has a maximum distance of approximately 1/5 (approximately 20%) compared to mechanisms a and b. The torque makes it possible to get over bumps.

Further, FIG. 13 is a diagram showing the maximum value of x _d normalized by the step height H for each mechanism. As shown in FIG. 13, the maximum value of x _d in mechanism c ₁ is 2/π (≈0.64) times as large as that in mechanisms a and b. Furthermore, the maximum value of x _d of mechanism c ₂ , which is a mechanism that increases the range of motion of mechanism c ₁ , is approximately 1/2.89 (≈0.35) times that of mechanism c ₁ , so mechanism a and mechanism When compared with the maximum value of x _d of b, it becomes 2/2.89π (≈0.22) times. This means that less torque is required for the same load. Mechanism c ₁ and mechanism c ₂ are effective not only for climbing over steps but also for climbing stairs because less clearance is required at the rear of the traveling device. On the other hand, mechanism _c2 has a wider range of motion, so the value of T becomes larger for the same angular velocity.

In this way, in this simulation, we developed a method for creating a geometric shape based on the parameters of the vertical distance or horizontal distance between the rotation axis and the contact point for the shape of the one-degree-of-freedom auxiliary mechanism that assists the traveling device in crossing steps. investigated. In addition, we simulated the operation of the traveling device to get over a step in several geometric shapes, including a shape using an involute curve as the shape of the auxiliary mechanism for getting over the step. As a result, it was found that shapes using involute curves, such as mechanism c ₁ and mechanism c ₂ , are capable of climbing over steps with less maximum torque compared to conventionally used bar shapes and circular arc shapes. Ta.

In addition, in this simulation, an example was explained in which the contact point of the auxiliary mechanism with the ground is located behind the axis of rotation of the auxiliary mechanism, but as shown in Fig. 14, Similar results can be obtained even with an auxiliary mechanism in which the contact point is located in front of the rotation axis.

○Shape of auxiliary mechanism○
Next, the shapes of the auxiliary mechanisms 10a and 10b created based on the above simulation results will be described using FIGS. 15 to 21. Note that since the auxiliary mechanisms 10a and 10b have the same shape, they will be described as the auxiliary mechanism 10 in the following description.

FIG. 15 is a diagram for explaining the shape of an involute curve-shaped auxiliary mechanism, FIG. 16 is a diagram for explaining the shape of a conventional bar-shaped auxiliary mechanism, and FIG. 17 is a diagram for explaining the shape of a conventional arc-shaped auxiliary mechanism. It is a figure for explaining the shape of an auxiliary mechanism. Here, in FIGS. 15 to 17, the left figure shows the shape of the auxiliary mechanism, the center figure shows the behavior of xd and yd when the auxiliary mechanism is rotationally driven, and the right figure shows the behavior of xd and yd when the auxiliary mechanism is rotationally driven. Shows the trajectory of the auxiliary mechanism.

Here, a shape that is advantageous for getting over a step is a shape that allows the rotating shaft to be lifted higher with a small torque. To make it possible to lift the rotating shaft higher with a small torque, the ground relative to the maximum vertical distance between the rotating shaft and the grounding point when the auxiliary mechanism rotates around the rotating shaft and lifts up the ground. The shape of the auxiliary mechanism is such that the ratio of the distance from the nearest point to the maximum height that can be lifted is increased. This ratio (ε _shape ) is expressed as below (Equation 10). y _{d_max} is the maximum value of the vertical distance (y _d ) between the rotation axis and the contact point, and y _{d_min} is the minimum value of the perpendicular distance (y _d ) between the rotation axis and the contact point. Moreover, x _{d_max} is the maximum value of the horizontal distance (x _d ) between the rotation axis and the contact point. That is, ε _shape is the ratio of the height of the step that can be overcome per driving torque in the auxiliary mechanism.

In the case of the auxiliary mechanism of the mechanism c ₁ having the involute curve shape shown in FIG. 15(A), ε _shape =1.86, and the mechanism c ₂ having the involute curve shape shown in FIG. 15(B) The auxiliary mechanism of is ε _shape =4.60.

On the other hand, in the rod-shaped auxiliary mechanism shown in FIG. 16, the maximum value of y _d and the maximum value of x _d are the rod length l, and the minimum value of y _d is 0, so ε _shape =1. Further, the arc-shaped auxiliary mechanism shown in FIG. 17(A) has ε _shape =√2, and the arc-shaped auxiliary mechanism shown in FIG. 17(B) has ε _shape =2. .

In addition, as shown in the right figures of FIGS. 15(A) and 15(B), the ground contact points of the mechanism c ₁ and the mechanism c ₂ change depending on the angle of the auxiliary mechanism with respect to the traveling device 5. It changes accordingly. In this case, the distance in the horizontal direction between the rotation axis of the mechanism c ₁ and the mechanism c ₂ and the grounding point is approximately 20% of the height of the step that can always be climbed over (the maximum height that can be pushed up). Further, the horizontal distance between the rotation axis and the grounding point of the mechanism c ₁ and the mechanism c ₂ is 25% or less of the maximum distance (y _{d_max} ) in the vertical direction between the rotation axis and the grounding point.

In this way, the driving assist device 1 can improve the performance of getting over a step by employing an assisting mechanism having an involute curve shape in at least a portion thereof. Furthermore, the auxiliary mechanism 10 has a shape in which the difference between the maximum vertical distance length and the minimum length of the vertical distance between the rotation axis and the contact point is larger than twice the horizontal distance between the rotation axis and the contact point. , the value of maximum torque can be reduced. Furthermore, since the driving assist device 1 has an involute curve shape, the horizontal distance between the rotating shaft and the contact point is always less than the maximum height that can be pushed up, so the height of the step that can be climbed and the torque required to get over the step are required. It is possible to achieve both a reduction in

FIG. 18 is a diagram for explaining the relationship between the shape of the auxiliary mechanism and the step-over height according to the embodiment. In the description of FIG. 18, the auxiliary mechanism 10A is used as an example of the auxiliary mechanism 10 having an involute curve shape. As shown in FIG. 18(A), in the auxiliary mechanism 10A, θ _lim is set so that the straight line connecting the starting point and ending point of the curve is parallel to the wall surface in the initial posture. In this case, x _d =a, y _d =aθ+h. The maximum height of the step that the auxiliary mechanism 10A can overcome is expressed as l ₁ =l ₂ =a√(1+θ _lim ² ) when h=0. Further, when h≠0, the maximum height of the step that the auxiliary mechanism 10A can overcome is l ₁ =√(x _d ² +y _d ² )=√(a ² +(aθ _lim ² +h ² )).

In this way, the height of the step that can be climbed over using the auxiliary mechanism 10A is the vertical distance _l1 between the rotation axis of the auxiliary mechanism 10A and the grounding point. That is, the auxiliary mechanism 10A can overcome a desired level difference by making the maximum distance in the vertical direction between the rotation axis of the auxiliary mechanism 10A and the grounding point longer than the height of the level difference that can be climbed over.

Furthermore, different shapes of the auxiliary mechanism 10 according to this embodiment will be explained using FIG. 19. The auxiliary mechanism 10B shown in FIG. 19(A) has a shape in which the start and end points of an involute curve are connected not by a straight line but by a curve. If the auxiliary mechanism 10 has a shape that has an involute curve in at least a part of the region like the auxiliary mechanism 10B, the shape is advantageous when climbing over a step.

Further, the auxiliary mechanism 10C shown in FIG. 19(B) has a shape in which the region connecting the starting point and the ending point of the curve does not touch the ground. As shown in Figure 20 (A), when the area connecting the start and end points of the curve touches the ground, a height offset occurs in the initial posture because a shaft that becomes the rotation axis of the auxiliary mechanism is introduced. It ends up. Therefore, the range of motion of the auxiliary mechanism ranges from 0° to approximately 250°, resulting in a narrow range of motion.

On the other hand, as shown in FIG. 20(B), the shape of the auxiliary mechanism 10C eliminates the height offset in the initial posture, so that the curved part touches the ground at any angle, so the range of motion is improved. can be expanded from 0° to 360°. Furthermore, as shown in FIG. 20(C), the auxiliary mechanism 10C as shown in the auxiliary mechanism 10C can overcome a step height of 2πa without energy loss, assuming that x _d = a. can.

Further, the ε _shape of the auxiliary mechanism 10C shown in FIG. 21 is ε _shape =6.36. In this way, the travel assist device 1 can widen the range of motion by adopting the assist mechanism 10C, which has a shape in which the region connecting the start point and end point of the curve does not touch the ground. The maximum torque can be reduced.

○Operation of driving assist device○
Next, a description will be given of how to get over a step using the auxiliary mechanism 10C having the shape shown in FIG. 19(B). FIG. 22 schematically shows the travel assist device 1 equipped with the assist mechanism C going up the stairs in Steps 1 to 6. The travel assist device 1 can overcome a step by driving the actuator 17 to rotationally drive the assist mechanism 10C. Furthermore, by making the auxiliary mechanism 10C have a shape in which the curved portion is always in contact with the ground, it is possible to prevent slippage at the edge portion of a step, for example.

●Another example of the driving assist device Next, another example of the configuration of the driving assist device 1 shown in FIG. 5 will be described. The travel assist device 1 shown in FIG. 23 has three assist mechanisms 10a, 10b, and 10c. The three auxiliary mechanisms 10a, 10b, and 10c are connected by connecting portions 15, respectively, and rotated by driving an actuator 17.

Further, the driving assist device 1 shown in FIG. 24 has four assist mechanisms 10a, 10b, 10c, and 10d. The auxiliary mechanisms 10a and 10b are connected by a connecting portion 15a, and are rotationally driven by driving an actuator 17a. The auxiliary mechanisms 10c and 10d are connected by a connecting portion 15b, and are rotationally driven by driving an actuator 17b. As described above, the number of auxiliary mechanisms 10 provided in the traveling auxiliary device 1 is not limited to two, and can be used depending on the road surface condition, the weight or drivability of the traveling device 5, the road surface condition, the purpose of use, etc. can.

Furthermore, as mentioned above, an auxiliary mechanism with a curved section has the advantage that less torque is required for lifting the rotating shaft with a pressing operation on the ground compared to the shape of wheels, bars, and reflections. By attaching members 13 as shown in FIGS. 25(A) to 25(C), running performance can be improved. The member 13 is a wheel or something similar to a wheel, and one or more members 13 are attached to the auxiliary mechanism 10 (for example, the auxiliary mechanism 10C). By attaching such a member 13 to the auxiliary mechanism 10, the travel auxiliary device 1 can reduce loss of potential energy due to horizontal changes in the position of the rotation axis, thereby improving drivability on flat ground. be able to. Furthermore, by attaching the member 13 to the auxiliary mechanism 10, the traveling assist device 1 can perform more detailed position control during traveling. In this way, by attaching the member 13 to the auxiliary mechanism 10 having a curved portion, the driving assist device 1 can improve the driving performance in various driving environments.

●Specific example of a traveling device A specific example of a traveling device including the traveling assist device 1 according to the present embodiment will be described using FIG. 26. The traveling device 5 shown in FIG. 26 includes a traveling device main body including a crawler-type traveling body 50 and a main body portion 55, and four auxiliary mechanisms 10 (10a, 10b, 10c, 10d, 10b, 10d are not included). A driving assist device 1 having a vehicle (as shown) is provided.

The crawler-type traveling body 50 is a crawler-type traveling body using a metal or rubber belt. The traveling body 50 mainly includes a drive wheel that transmits a driving force for rotating the traveling body 50 to the crawler belt, and two wheels rotatably attached to the traveling body 50. An in-wheel motor that transmits rotational force to the drive wheel is provided inside the drive wheel. The traveling body 50 transmits the driving force (rotational force) transmitted to the driving wheels by the in-wheel motor to the rolling wheels via crawler belts.

A track-type traveling object has a wider ground contact area than a traveling object such as a car that runs on tires, and can run stably even in an environment with poor footing, for example. In addition, a traveling body that runs on tires requires a turning space when making rotational movements, whereas a traveling device equipped with a track-type traveling body can perform so-called super pivot turns. , allows for smooth rotation even in limited space.

Further, the traveling device 5 is installed so that the two traveling bodies 50 are substantially parallel to each other with the main body portion 55 in between, that is, in a state where the traveling device 5 can travel. Note that the number of running bodies is not limited to two, and may be three or more. For example, the traveling device 5 may be installed in a state in which the traveling device 5 can travel, such as by arranging three crawler-type traveling bodies in three parallel rows. Further, for example, the traveling device 5 may have four crawler-type traveling bodies arranged in front, rear, left, and right directions like automobile tires.

The traveling device 5 described above can be used in various usage scenes by attaching devices or members to the main body portion 55 for realizing functions depending on the purpose of use. The traveling device 5 is used, for example, as a work robot that takes advantage of its high turning ability and performs light work such as transporting articles at a base such as a factory or warehouse with narrow passages. In the case of such a working robot, the traveling device 5 is attached with, for example, a loading platform for transportation and a movable arm for light work.

The traveling device 5 is also used, for example, for rescue purposes or reconstruction support purposes at disaster sites, agricultural purposes, or construction sites. In such applications, for example, in an environment where the road surface is rough due to scattered debris and garbage, the traveling device 5 takes advantage of the characteristics such as the running stability of the track type traveling body 10 to reduce the risk of malfunctions occurring during traveling. can be reduced.

Furthermore, by being equipped with a photographing device and a display device, the traveling device 5 can also be used as a telepresence robot that realizes two-way communication (remote communication) between a user within the base of the traveling device 5 and a user in a remote location. be done. By using a telepresence robot, it is possible to remotely manage or maintain equipment within a base, or to confirm the location or movement line of people within a base. Furthermore, the traveling device 5 may be configured to travel in response to a remote control from a user located at a remote location.

Note that the traveling assist device 1 included in the traveling device 5 having the track-type traveling body 50 shown in FIG. 26 has two auxiliary mechanisms 10 (10a, 10b) as shown in FIG. It may also have a shape. Further, the traveling assist device 1 may be configured to be connected to a traveling device main body including only the main body portion 55. In this case, the auxiliary mechanism 10 provided in the travel assist device 1 takes on the function of a traveling body of the travel device 5.

●Summary●
As described above, the traveling assist device 1 according to an embodiment of the present invention includes the auxiliary mechanism 10 that transmits an upward external force to the traveling device 5 by rotationally driving the traveling device 5 in the grounded state. The difference between the maximum distance (y _{d_max} ) and the minimum distance (y _{d_min} ) in the vertical direction between the rotation axis and the grounding point of the auxiliary mechanism 10 during rotational driving is equal to the horizontal distance (x _{d_max} ). Thereby, the driving assist device 1 can reduce the value of the maximum torque required to get over the step, so that it is possible to achieve both the height of the step that can be climbed over and the reduction in the torque required to get over the step.

Furthermore, in the travel assist device 1 according to the embodiment of the present invention, the maximum distance (y _{d_max} ) in the vertical direction between the rotating shaft and the grounding point is longer than the height of the step that the travel assist device 1 can overcome. Further, the horizontal distance (x _d ) between the rotation axis and the grounding point is approximately 20% of the height of the object that the travel assist device 1 can climb over. As a result, in the driving assist device 1, the horizontal distance between the rotating shaft and the contact point is always lower than the maximum height that can be pushed up, so it is possible to achieve both the height of the step that can be climbed over and the reduction of the torque required to get over the step. can.

Furthermore, in the travel assist device 1 according to an embodiment of the present invention, at least a portion of the assist mechanism 10 has an involute curve shape. Further, the auxiliary mechanism 10 (for example, the auxiliary mechanism 10C) has a shape in which a region connecting the starting point and the ending point of the involute curve shape does not touch the ground. In this way, the travel assist device 1 can widen the range of motion by adopting the assist mechanism 10 having a shape in which the region connecting the starting point and the ending point of the curve does not touch the ground, so it is possible to expand the range of motion, which is necessary for climbing over steps. The maximum torque can be reduced. In addition, the travel assist device 1 can prevent slippage at the edge portion of a step, for example, by shaping the assist mechanism 10 so that the curved portion always contacts the ground.

Further, the traveling device 5 according to an embodiment of the present invention includes a traveling assist device 1 and a main body portion 55. Further, the travel assist device 1 is connected to the travel device 5 by a ratchet method, and transmits driving force in one direction to the travel device 5 by rotationally driving the auxiliary mechanism 10. Thereby, the traveling device 5 connects the traveling auxiliary device 1 with a ratchet joint method (ratchet method), and by transmitting driving force in one direction to the traveling device 5 by the rotational drive of the auxiliary mechanism 10, the traveling device 5 can climb over a step. Performance can be improved.

●Supplement●
Although the travel assist device and the travel device according to one embodiment of the present invention have been described so far, the present invention is not limited to the above-described embodiment, and other embodiments may be added, changed, or deleted as appropriate. Modifications can be made within the scope of those skilled in the art, and any embodiment is included within the scope of the present invention as long as the effects and effects of the present invention are achieved.

1 Traveling auxiliary device 5 Traveling device 10 (10a, 10b, 10c, 10d) Auxiliary mechanism 15 Connection section 17 Actuator 50a, 50b Traveling body 55 Main body

Japanese Patent Application Publication No. 2014-19210

Claims (7)

A traveling device comprising at least two traveling bodies, a main body that supports the at least two traveling bodies, and a traveling assistance device connected to the main body ,
an auxiliary mechanism that transmits an external force for lifting the traveling body to the main body by rotationally driving it in a grounded state;
The auxiliary mechanism has an involute curve-shaped region that is in contact with the ground, and a region that does not touch the ground when the starting point and end point of the involute curve shape are connected,
The difference between the maximum distance and the minimum distance in the vertical direction between the rotating shaft of the auxiliary mechanism and the grounding point during rotational driving in a grounded state is greater than twice the horizontal distance between the rotating shaft and the grounding point. A traveling device characterized by: The traveling device according to claim 1, wherein a maximum distance in the vertical direction between the rotation axis and the grounding point is longer than a height of a step that the traveling assist device can overcome. 3. The traveling device according to claim 2, wherein the distance in the horizontal direction between the rotating shaft and the grounding point is approximately 20% of the height of a step that the traveling assist device can overcome. 4. A horizontal distance between the rotating shaft and the grounding point is 25% or less of a maximum vertical distance between the rotating shaft and the grounding point. The traveling device described in . The traveling device according to any one of claims 1 to 4, wherein the auxiliary mechanism changes the position of the grounding point during rotational driving in a grounded state. The traveling device according to any one of claims 1 to 5, wherein the auxiliary mechanism has a constant horizontal distance between the rotating shaft and the grounding point during rotational driving in a grounded state. . The travel assist device is connected to the main body portion by a ratchet method,
The traveling device according to any one of claims 1 to 6, wherein driving force in one direction is transmitted to the main body by rotationally driving the auxiliary mechanism.