JP2018030515A - Traveling device - Google Patents

Abstract

When a target speed is set according to a wheelbase length and speed control is performed, when an external force is applied due to a step on a running surface or the like, the wheelbase length is suddenly shortened depending on the structure of the running device, and the speed is reduced. May fluctuate, and it may not be possible to get over the step or the like. A traveling device includes a front wheel support member that rotatably supports a front wheel, a rear wheel support member that rotatably supports a rear wheel, a drive unit that drives at least one of a front wheel and a rear wheel, and a user. By changing the relative position of the front wheel support member and the rear wheel support member, an adjustment mechanism that adjusts the wheel base length of the front wheel and the rear wheel, and a measuring unit that measures the relative position of the front wheel support member and the rear wheel support member A control unit that controls the drive unit based on the target speed associated with the measurement result of the measurement unit, and a change in the relative position of the front wheel support member and the rear wheel support member when an external force acts on the front wheel from the running surface. And an absorbing mechanism for absorbing at least a part of the external force so as to reduce the pressure. [Selection diagram] FIG.

Description

  The present invention relates to a traveling device on which a user travels.

  In recent years, personal mobility has been in the spotlight. Personal mobility is often manufactured in a small size by giving priority to a small turn, and therefore there is a problem that stability at high speed is lacking. In addition to personal mobility, vehicles that can adjust the wheelbase length have been proposed from the viewpoint of enhancing stability during high-speed travel (see, for example, Patent Documents 1 and 2).

JP-A-1-106717 JP 2005-231415 A

  When speed control is performed by setting a target speed according to the wheelbase length, the wheelbase length may be shortened unexpectedly depending on the structure of the traveling device when the external force is received from a step on the running surface, etc. Therefore, it may not be possible to get over the level difference.

  The present invention has been made to solve such a problem, and provides a traveling device that can more reliably overcome a step or the like on a traveling surface.

  A traveling device according to a first aspect of the present invention is a traveling device that has at least a front wheel and a rear wheel in a traveling direction and travels by a user riding on the front wheel support member that rotatably supports the front wheel. A rear wheel support member that rotatably supports the rear wheel, a drive unit that drives at least one of the front wheel and the rear wheel, and a user changing the relative position of the front wheel support member and the rear wheel support member to thereby change the front wheel And an adjustment mechanism that adjusts the wheel base length of the rear wheel, a measurement unit that measures the relative position of the front wheel support member and the rear wheel support member, and a drive unit based on the target speed associated with the measurement result of the measurement unit And a control unit that controls, and an absorption mechanism that absorbs at least a part of the external force so as to reduce a change in the relative position of the front wheel support member and the rear wheel support member when an external force acts on the front wheel from the traveling surface.

  With such a configuration, even if the wheel base length is shortened by an external force applied to the front wheel, the relative function of the front wheel support member and the rear wheel support member measured by the measurement unit with respect to the shortening amount of the wheel base length due to the action of the absorption mechanism. The amount of change in position is small. Therefore, the target speed does not change rapidly, and the step torque can be overcome while maintaining the driving torque.

  A traveling device according to a second aspect of the present invention is a traveling device that has at least front wheels and rear wheels in the traveling direction and travels by a user riding on the front wheel support member that rotatably supports the front wheels. A rear wheel support member that rotatably supports the rear wheel, a drive unit that drives at least one of the front wheel and the rear wheel, and a user changing the relative position of the front wheel support member and the rear wheel support member to thereby change the front wheel And an adjustment mechanism that adjusts the wheel base length of the rear wheel, a measurement unit that measures the relative position of the front wheel support member and the rear wheel support member, and a drive unit based on the target speed associated with the measurement result of the measurement unit A control unit that controls the target speed so as to increase as the wheel base length increases, and the control unit adjusts the target speed when the adjustment mechanism is adjusted to increase the wheel base length. Than the response time to follow, a longer response time to follow the target speed when the adjustment mechanism as wheelbase length is reduced is adjusted.

  With such a configuration, even when the wheelbase length is unexpectedly shortened due to a step on the running surface, the target speed does not drop suddenly, and the driving torque for overcoming the step, etc. is provided at least for a while. It can be expected to maintain.

A traveling device according to a third aspect of the present invention is a traveling device that has at least a front wheel and a rear wheel in the traveling direction and travels while the user is riding on the front wheel support member that rotatably supports the front wheel. A rear wheel support member that rotatably supports the rear wheel, a drive unit that drives at least one of the front wheel and the rear wheel, and a user changing the relative position of the front wheel support member and the rear wheel support member to thereby change the front wheel And an adjustment mechanism that adjusts the wheel base length of the rear wheel, a measurement unit that measures the relative position of the front wheel support member and the rear wheel support member, and a drive unit based on the target speed associated with the measurement result of the measurement unit The target speed is associated with the wheel base length so as to increase as the wheel base length increases, and a speed greater than 0 is associated with the shortest wheel base length.
With such a configuration, even when the front wheel receives an external force from a step or the like on the traveling surface and the wheelbase length becomes the shortest, the driving force for overcoming a certain step is maintained.

  According to the present invention, it is possible to provide a traveling device that can more reliably overcome a step or the like of a traveling surface while satisfying both a good small turn during low-speed traveling and stability during high-speed traveling.

It is a side surface general view at the time of low speed driving | running | working of the traveling apparatus which concerns on 1st Example. FIG. 2 is a schematic top view of the traveling device of FIG. 1. FIG. 2 is a schematic side view of the traveling device of FIG. 1 when traveling at high speed. It is explanatory drawing explaining the relationship between the wheelbase length before and behind level | step contact, and a rotation angle. It is a control block diagram of a traveling apparatus. It is a graph which shows the relationship between a rotation angle and target speed. It is a table which shows the relationship between the rotation angle of another example, and target speed. It is a flowchart which shows the process in driving | running | working. It is a side view outline of the traveling device concerning the 2nd example. It is a side surface schematic diagram of the traveling apparatus which concerns on 3rd Example. It is explanatory drawing explaining the relationship between the wheelbase length before and behind level | step contact, and a rotation angle. It is a graph which shows the response time which follows the target speed in the 1st example. It is a graph which shows the response time which follows the target speed in the 2nd example. It is a graph which shows the response time which follows the target speed in the 3rd example. It is a graph which shows the relationship between the rotation angle which concerns on 4th Example, and target speed.

  Hereinafter, the present invention will be described through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. In addition, all of the configurations described in the embodiments are not necessarily essential as means for solving the problem.

  A first embodiment will be described. FIG. 1 is a schematic side view of the traveling device 100 according to the first embodiment during low-speed traveling, and FIG. 2 is a top schematic view of the traveling device 100 in the state of FIG. 1 observed from above. In FIG. 2, the user 900 indicated by a dotted line in FIG. 1 is omitted.

  The traveling device 100 is a kind of personal mobility, and is an electric moving vehicle that assumes that the user stands and gets on. The traveling device 100 includes one front wheel 101 and two rear wheels 102 (a right rear wheel 102a and a left rear wheel 102b) in the traveling direction. The front wheel 101 changes its direction when the user 900 operates the handle 115 and functions as a steered wheel. The right rear wheel 102a and the left rear wheel 102b are connected by an axle 103, and are driven by a motor and a speed reduction mechanism (not shown) to function as drive wheels. The traveling device 100 is a static stable vehicle that is grounded at three points by three wheels and that stands by itself even in a parking state where the user 900 is not on board.

  The front wheel 101 is rotatably supported by a front wheel support member 110. The front wheel support member 110 includes a front column 111 and a fork 112. The fork 112 is fixed to one end side of the front column 111 and rotatably supports the front wheel 101 with the front wheel 101 sandwiched from both sides. A handle 115 is fixed to the other end side of the front column 111 across the coil over 116 so as to extend in the direction of the rotation axis of the front wheel 101. When the user 900 turns the handle 115, the front column 111 transmits the operation force to change the direction of the front wheel 101.

  The coil over 116 is an absorption mechanism provided at a position near one end of the front column 111 where the fork 112 is fixed. The coil over 116 is configured by combining a coil spring and a shock absorber, and absorbs the impact when an external force acts on the front wheel 101 from the running surface due to a step or the like.

  The rear wheel 102 is rotatably supported by a rear wheel support member 120. The rear wheel support member 120 includes a rear column 121 and a main body 122. The main body 122 fixedly supports one end of the rear column 121, and rotatably supports the right rear wheel 102a and the left rear wheel 102b via the axle 103. The main body 122 also functions as a housing that houses the motor, the speed reduction mechanism, a battery that supplies power to the motor, and the like. On the upper surface of the main body 122, a step 141 for the user 900 to place his / her foot is provided.

The front wheel support member 110 and the rear wheel support member 120 are connected to each other through a turning joint 131 and a hinge joint 132. The swivel joint 131 is fixed at a position near the other end of the front column 111 constituting the front wheel support member 110 to which the handle 115 is fixed. Furthermore, pivot joint 131 is pivoted to the hinge joint 132, the extending direction parallel to the pivot axis _{T A} around the front pillar 111, to rotate relative to the hinge joint 132. The hinge joint 132 is pivotally connected to the other end of the rear column 121 constituting the rear wheel support member 120 on the side opposite to the one end supported by the main body 122, and is parallel to the extending direction of the axle 103. It rotates relative to the rear column 121 around the hinge axis _HA .

This structure, the user 900, when turning the handle 115, a front wheel supporting member 110 is changed the direction of the front wheel 101 to pivot the pivot axis T _A around against the rear wheel support member 120. Further, when the user 900 tilts the handle 115 forward with respect to the traveling direction, the operation is transmitted, whereby the front wheel support member 110 and the rear wheel support member 120 rotate relatively around the hinge axis _HA. Thus, the angle formed by the front column 111 and the rear column 121 can be reduced. When the angle formed by the front column 111 and the rear column 121 decreases, the WB length, which is the distance between the wheel bases (WB) of the front wheel 101 and the rear wheel 102, decreases. Conversely, when the user 900 tilts the handle 115 rearward with respect to the traveling direction, the front wheel support member 110 and the rear wheel support member 120 rotate relatively around the hinge axis _HA , and the front column 111 and the rear The angle formed by the side columns 121 can be increased. As the angle formed by the front column 111 and the rear column 121 increases, the WB length increases. That is, the user 900 can shorten or lengthen the WB length by causing his / her operation as a rotational force.

An urging spring 133 is attached in the vicinity of the hinge joint 132. The biasing spring 133 exerts a biasing force around the hinge axis _{HA in} a rotational direction that reduces the angle formed by the front column 111 and the rear column 121. The biasing spring 133 is, for example, a torsion spring. When the user 900 does not touch the handle 115, the urging force of the urging spring 133 is changed so that the angle formed by the front column 111 and the rear column 121 becomes the minimum angle in the structure, while the user 900 It is set to such an extent that the handle 115 can be easily tilted backward with respect to the traveling direction. Therefore, the user 900 can adjust the angle formed by the front strut 111 and the rear strut 121 by changing at least one of the weight on the handle 115 and the weight on the step 141, and thus can adjust the WB length. That is, the mechanism for connecting the front column 111 and the rear column 121 via the hinge joint 132 functions as an adjustment mechanism for the user 900 to adjust the WB length.

A rotation angle sensor 134 is attached in the vicinity of the hinge joint 132. The rotation angle sensor 134 outputs an angle formed by the front column 111 and the rear column 121 around the hinge axis _HA . That is, the rotation angle sensor 134 functions as a measurement unit that measures the relative position of the front wheel support member 110 and the rear wheel support member 120. The rotation angle sensor 134 is, for example, a rotary encoder. The output of the rotation angle sensor 134 is transmitted to a control unit described later.

  The traveling device 100 travels at a low speed if the WB length is short, and travels at a high speed if the WB length is long. FIG. 1 shows a state during low-speed traveling with a short WB length. FIG. 3 is a schematic side view of the traveling device 100 similar to that in FIG. 1, but shows a state during high-speed traveling with a long WB length.

As shown in the figure, the angle formed by the front column 111 and the rear column 121 is defined as a rotation angle θ, with the relative opening direction being positive. The minimum value (minimum angle) that the rotation angle θ can take is θ _MIN , and the maximum value (maximum angle) is θ _MAX . For example, θ _MIN = 10 degrees and θ _MAX = 80 degrees. In other words, the structural restriction member is provided so that the rotation angle θ falls within the range of θ _MIN and θ _MAX .

  The WB length has a one-to-one correspondence with the rotation angle θ when there is no action of the coil over 116 described later, and can be converted by a function of WB length = f (θ). Therefore, the WB length can be adjusted by changing the rotation angle θ. The traveling device 100 in the present embodiment accelerates when the user 900 increases the rotation angle θ, and decelerates when the user 900 decreases the rotation angle θ. That is, the target speed is associated with the rotation angle θ, and when the rotation angle θ changes, acceleration / deceleration is performed so that the target speed corresponding to the target speed is reached.

  As the rotation angle θ is reduced, the WB length is shortened, so that a small turn is advantageous. That is, it can move around in a narrow place. On the contrary, when the rotation angle θ is increased, the WB length is increased, so that the running stability, particularly the straight traveling performance is improved. That is, even if the vehicle travels at a high speed, it is difficult to receive a swing due to a step on the road surface. Further, since the speed and the WB length change in conjunction with each other, the WB length does not become long although the speed is low, and the movement can be performed with the minimum necessary projection area at the speed. That is, the area on the road surface required for the traveling device 100 to move is small, and no extra space is required. This is particularly effective when parked. Further, if the user 900 tilts the handle 115 back and forth, both the speed and the WB length can be changed in conjunction with each other, so that it is simple and easy as a driving operation.

  Furthermore, the adjustment of the WB length is realized by transmitting an acting force generated by the operation of the user 900, and an actuator for adjusting the WB length is not required. Therefore, the traveling device 100 in this embodiment is reduced in weight as a whole device. For example, the user 900 can easily bring the traveling device 100 into the train, and the convenience that is not available in personal mobility so far. Can be provided.

  FIG. 4 is an explanatory diagram for explaining the relationship between the WB length and the rotation angle θ immediately before and immediately after the front wheel 101 contacts the step BP present on the traveling surface. 4A shows the state immediately before, and FIG. 4B shows the state immediately after.

As shown in FIG. 4A, when the vehicle is traveling with the rotational angle θ being θ ₀ , the vehicle is traveling at a target speed (for example, V ₀ ) associated with the rotational angle θ ₀ . Control unit, the driving wheel so that the speed V ₀ is maintained to rotate. During normal travel in which the travel surface is a flat surface, the coil over 116 has a natural length, and the WB length is WB ₀ corresponding to the rotation angle θ ₀ until just before contact with the step BP shown in FIG.

When the front wheel 101 contacts the step BP at the speed V ₀ , as shown in FIG. 4B, the front wheel 101 receives an external force from the step BP, and at least a part of the front wheel 101 works as a force to push the front wheel 101 backward. On the other hand, the rear wheel 102 tends to move forward due to the propulsive force and inertia as a driving wheel.

If the coil over 116 is not provided, the front strut 111 and the rear strut 121 rotate relatively around the hinge axis _HA due to the action of the two thick arrows shown in FIG. The rotation angle θ ₀ changes rapidly in the direction of decreasing. As will be described later, since the target speed is associated with an increase as the rotation angle θ increases, the associated target speed may decrease instantaneously when the rotation angle θ decreases rapidly. Then, the driving force of the rear wheel 102 is reduced at a stretch, and a situation may occur in which the step BP cannot be overcome.

However, in this embodiment, a coil over 116 is provided. Specifically, the coil over 116 is formed between the position where the swivel joint 131 pivoted on the hinge joint 132 is provided on the front column 111 and the other end where the fork 112 supporting the front wheel 101 is fixed. Is provided. In addition, the coil over 116 absorbs at least a part of the external force when the wheel 101 receives an external force that pushes the wheel 101 backward within the range of θ _MIN and θ _MAX that the rotation angle θ can take. The orientation is adjusted and arranged.

Therefore, in the traveling device 100 according to this embodiment, at least a part of the external force that pushes the wheel 101 backward is absorbed by the coil over 116 immediately after the front wheel 101 contacts the step BP at the speed V ₀ . At this time, if the coil over 116 is shortened by the length d in the traveling direction due to the absorption, the WB length is shortened to WB ₁ (= WB ₀ -d). However, this action of the coil-over 116, the relative positional relationship between the front pillar 111 and the rear pillar 121 is maintained before and after contact with the stepped BP, both the rotation angle of theta keep theta _0.

If the rotation angle θ remains θ ₀ immediately after the front wheel 101 contacts the step BP, the associated target speed V ₀ is also maintained, so that the driving force of the rear wheel 102 does not decrease at a stretch. It can be expected that the step BP can be overcome with a higher probability. After the front wheel 101 comes into contact with the step BP and the coil over 116 starts to shrink or after it has shrunk, even if the rotation angle θ gradually becomes smaller than θ ₀ , the front wheel 101 gets over the step BP at the initial stage. Since a large driving force can be secured, it is advantageous in any case over the step.

  FIG. 5 is a control block diagram of traveling device 100. The control unit 200 is a CPU, for example, and is accommodated in the main body unit 122. The drive wheel unit 210 includes a drive circuit and a motor for driving the rear wheel 102 that is a drive wheel, and is accommodated in the main body 122. The control unit 200 controls the rotation of the rear wheel 102 by sending a drive signal to the drive wheel unit 210.

  The vehicle speed sensor 220 monitors the amount of rotation of the rear wheel 102 or the axle 103 and detects the speed of the traveling device 100. The vehicle speed sensor 220 transmits the detection result as a speed signal to the control unit 200 in response to a request from the control unit 200. The rotation angle sensor 134 detects the rotation angle θ as described above. The rotation angle sensor 134 transmits the detection result to the control unit 200 as a rotation angle signal in response to a request from the control unit 200.

  The load sensor 240 is, for example, a piezoelectric film that detects a load applied to the step 141, and is embedded in the step 141. The load sensor 240 transmits the detection result as a load signal to the control unit 200 in response to a request from the control unit 200.

  The memory 250 is a non-volatile storage medium, and for example, a solid state drive is used. The memory 250 stores various parameter values, functions, lookup tables, and the like used for control, in addition to the control program for controlling the traveling device 100. The memory 250 stores a conversion table 251 that converts the rotation angle θ into a target speed.

FIG. 6 is a graph showing the relationship between the rotation angle θ and the target speed as an example of the conversion table 251 for converting the rotation angle θ into the target speed. As shown in the figure, the target speed is expressed as a linear function of the rotation angle θ, and is set so that the target speed increases as the rotation angle θ increases. The target speed is 0 at the minimum angle θ _MIN (degrees), and the target speed is the maximum speed V _m (km / h) at the maximum angle θ _MAX (degrees). Thus, the conversion table 251 may be in a function format.

  FIG. 7 is a table showing the relationship between the rotation angle θ and the target speed as another example of the conversion table 251 for converting the rotation angle θ into the target speed. In the example of FIG. 6, the continuously changing target speed is associated with the continuously changing rotation angle θ. In the example of FIG. 7, the continuously changing rotation angle θ is divided into a plurality of groups, and one target speed is associated with each group.

As illustrated, the rotation angle theta is, theta when it is more than theta less than _{1 MIN} associated target speed 0 (km / h), the target speed 5.0 is less than theta ₁ or θ ₂ (km / h) in correspondence, and when θ ₂ or more and less than θ ₃ , target speed 10.0 (km / h) is associated, and when θ ₃ or more and θ _MAX or less, target speed 15.0 (km / h) Associate. The conversion table 251 in such a case can adopt a lookup table format. In this way, when the target speed is associated with the range of the rotation angle θ that has a certain width, the target speed does not change little by little due to the shaking of the body of the user 900, for example. I can expect. Of course, hysteresis may be given to the boundary of the range, and if the boundary of the range is made different between acceleration and deceleration, a smoother speed change can be expected.

  The association between the rotation angle θ and the target speed is not limited to the examples in FIGS. 5 and 6, and various associations are possible. For example, it is possible to arrange such that the change amount of the target speed with respect to the change amount of the rotation angle θ is set small in the low speed region and large in the high speed region.

  This is because the small turn at the time of low speed travel is short because the WB length is short, and the stability at high speed travel is because the WB length is long, so the WB length and the target speed should be directly associated with each other. . However, the traveling device 100 according to the present embodiment associates the target speed with the rotation angle θ and provides the coil over 116 on the front support column 111, thereby enjoying the advantages of small turning and stability, while rapidly increasing the WB length. The possibility of being able to get over the level difference on the running surface is increased regardless of any changes.

  Next, the traveling process in the present embodiment will be described. FIG. 8 is a flowchart showing processing during traveling. The flow starts when the power switch is turned on and a signal with a load is received from the load sensor 240, that is, when the user 900 gets on board.

  In step S101, the control unit 200 acquires a rotation angle signal from the rotation angle sensor 134 and calculates the current rotation angle θ. In step S102, the calculated rotation angle θ is applied to the conversion table 251 read from the memory 250, and the target speed is set.

  After setting the target speed, the control unit 200 proceeds to step S103 and transmits an acceleration / deceleration drive signal to the drive wheel unit 210. Specifically, first, a speed signal is received from the vehicle speed sensor 220 and the current speed is confirmed. If the target speed is larger than the current speed, a driving signal for accelerating is transmitted to the driving wheel unit 210, and if the target speed is smaller than the current speed, a driving signal for decelerating is transmitted to the driving wheel unit 210.

  The control unit 200 monitors whether the rotation angle θ has changed during acceleration / deceleration, that is, whether the user 900 has tilted the handle 115 back and forth (step S104). If it is determined that the rotation angle θ has changed, the process starts again from step S101. If it is determined that there is no change, the process proceeds to step S105. When the conversion table as shown in FIG. 7 is adopted, it is determined that the rotation angle θ does not change while the rotation angle θ remains in one range.

  In step S105, the control unit 200 receives a speed signal from the vehicle speed sensor 220, and determines whether or not the target speed has been reached. If it is determined that the target speed has not been reached, the process returns to step S103 to continue acceleration / deceleration. If it is determined that the target speed has been reached, the process proceeds to step S106. In step S106, it is confirmed whether or not the target speed is zero. If the target speed is 0, the traveling device 100 is stopped at the time of step S106. Otherwise, since the vehicle is traveling at the target speed, the control unit 200 transmits a drive signal to the drive wheel unit 210 so as to maintain the travel at the speed (step S107).

  The control unit 200 also monitors whether the rotation angle θ has changed, that is, whether the user 900 has tilted the handle 115 back and forth while traveling at a constant speed in step S107 (step S108). If it is determined that the rotation angle θ has changed, the process returns to step S101. If it is determined that there is no change, the process returns to step S107 to continue constant speed running. At this time, even if the front wheel 101 comes into contact with the step BP, the rotation angle θ does not change immediately after that, so the control unit 200 tries to continue the constant speed running.

  If it is confirmed in step S106 that the target speed is 0, the process proceeds to step S109, and it is determined from the load signal received from the load sensor 240 whether the user 900 has moved down. If it is determined that the user 900 is not getting off, that is, there is a load, the process returns to step S101 to continue the traveling control. If it is determined that the aircraft has been removed, the series of processes is terminated.

  In the first embodiment described above, when an external force is applied to the front wheel 101 from the running surface, at least a part of the external force is applied so as to reduce the change in the relative position of the front wheel support member 110 and the rear wheel support member 120. A coil over 116 is employed as an absorbing mechanism for absorbing. However, the absorption mechanism is not limited to this. Various modes can be adopted as long as the absorption mechanism is provided so that the influence of the external force does not affect the detection result of the rotation angle sensor 134 that detects the rotation angle θ immediately after the external force is applied to the front wheel 101. As long as it functions as an elastic member instead of the coil over 116, for example, a leaf spring that bends by an external force from the step BP may be provided.

  Moreover, as long as it is a measurement part which measures the relative position of the front wheel support member 110 and the rear wheel support member 120, you may employ | adopt not only the rotation angle sensor 134 but another sensor. For example, a gravity sensor may be provided on each of the front column 111 and the rear column 121 to detect the respective inclinations with respect to the direction of gravity.

  Next, a second embodiment will be described. FIG. 9 is a schematic side view of the traveling device 510 according to the second embodiment. The traveling device 510 does not include the coil over 116 with respect to the traveling device 100 of the first embodiment, but includes a rotary damper 511 instead. Therefore, elements having the same functions as those of the traveling device 100 are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted. In addition, the configuration of the control block and the processing flow are the same as those described with reference to FIGS. Therefore, in the following description, differences as hardware will be mainly described.

The rotary damper 511 is provided in the vicinity of the hinge joint 132 so as to act on the rotation of the hinge shaft _HA of the hinge joint 132. The rotary damper 511 is an example of a rotation suppression mechanism that suppresses a change in the relative angle between the front column 111 of the front wheel support member 110 and the rear column 121 of the rear wheel support member 120 on the hinge axis _HA . Specifically, for example, the rotary damper 511 is filled with silicon oil in a sealed cylindrical space, and a plurality of rotary dampers 511 are provided on the rotary shaft when the rotary shaft directly connected to the hinge shaft rotates. The rotational viscosity resistance is generated by the pressure that the vane receives from the silicone oil.

The traveling device 510 suppresses a sudden change in the rotation angle θ by providing the rotary damper 511. That is, when an external force acts on the front wheel 101 from the traveling surface, it functions as an absorption mechanism that absorbs at least a part of the external force so as to reduce a change in the relative position of the front column 111 and the rear column 121. Although the rotation angle θ is not maintained at θ ₀ immediately after the front wheel 101 contacts the step BP as in the first embodiment, the rotary damper 511 can delay the change in which the rotation angle θ decreases. . Therefore, it can be expected that the driving force of the rear wheel 102 does not decrease at a stretch and the step BP can be overcome with a higher probability.

  The rotary damper 511 is better if the resistance in the direction of decreasing the rotation angle θ is larger than the resistance in the increasing direction. With such a rotary damper, when the user 900 wants to increase the speed, the operation of the steering wheel is unlikely to be hindered.

  Further, the rotation suppression mechanism is not limited to the rotary damper, and other mechanisms may be employed. For example, an impact detection sensor that detects an abrupt impact is provided, and a ratchet mechanism provided between the front support column 111 and the rear support column 121 is operated by a solenoid that protrudes when the sensor detects the impact, thereby temporarily Alternatively, the relative rotation of the two may be prevented. Of course, not only the ratchet mechanism but other mechanisms such as an electromagnetic brake may be adopted.

  Next, a third embodiment will be described. In the first embodiment and the second embodiment, the probability of being able to get over the step BP on the traveling surface is increased by using the absorption mechanism as hardware in the traveling device. However, in this embodiment, the control unit 200 controls the similarity. So that the effect of.

  FIG. 10 is a schematic side view of a traveling device 600 according to the third embodiment. The hardware configuration of the traveling device 600 is the same as that obtained by removing the rotary damper 511 from the traveling device 510 according to the second embodiment. Elements having the same functions as those of the traveling device 100 according to the first embodiment are denoted by the same reference numerals as those in the first embodiment, and description thereof is omitted. Further, the configuration and processing flow of the control block are the same as those described with reference to FIGS. 5 to 8 unless otherwise specified.

  FIG. 11 is an explanatory diagram for explaining the relationship between the WB length before and after the step contact and the rotation angle θ. FIG. 11A shows the state immediately before, and FIG. 11B shows the state immediately after.

As shown in FIG. 11A, when the vehicle is traveling with the rotation angle θ being θ ₀ , the vehicle is traveling at a target speed (for example, V ₀ ) associated with the rotation angle θ ₀ . Control unit, the driving wheel so that the speed V ₀ is maintained to rotate. Until immediately before contact with the step BP, the WB length is WB ₀ corresponding to the rotation angle θ ₀ .

When the front wheel 101 comes into contact with the step BP at the speed V ₀ , as shown in FIG. 11B, the front wheel 101 receives an external force from the step BP, and at least a part of the front wheel 101 works as a force to push the wheel 101 backward. On the other hand, the rear wheel 102 tends to move forward due to the propulsive force and inertia as a driving wheel. Since the traveling device 600 does not include the absorption mechanism in the above-described embodiment, the front column 111 and the rear column 121 rotate relatively around the hinge axis _HA by the action of the force indicated by the two thick arrows. Thus, the rotation angle θ changes suddenly in the direction of decreasing and becomes θ ₁ . Then, the WB length contracts by the length d with respect to the traveling direction and changes from WB ₀ to WB ₁ .

Here, if the target speed is instantaneously changed from V ₀ corresponding to θ ₀ to V _L corresponding to θ ₁ , the driving force of the rear wheel 102 is reduced at a stretch and the step BP cannot be overcome. Can occur. Therefore, in this embodiment, when the adjustment mechanism is adjusted so that the WB length becomes longer, the target speed is reached when the adjustment mechanism is adjusted so that the WB length becomes shorter than the response time following the target speed. By increasing the response time to follow, the probability of getting over the step BP is increased.

  Some examples of such control methods will be described. FIG. 12 is a graph showing the response time following the target speed in the first example. The horizontal axis represents time (s), and the vertical axis represents the speed of the traveling device 600.

FIG. 12A shows a change when the user 900 increases the WB length by operating the handle 115, for example. From the state WB length that when WB ₀ of ₍₀ theta is the rotation angle at this time), running in the current velocity _{V 0} associated with theta _0, at time _{t 1,} WB length WB _H (this It is assumed that the rotation angle is widened to θ _H ). Assuming that the target speed associated with the rotation angle θ _H is V _H , the control unit 200 transmits a driving signal for accelerating to the driving wheel unit 210 from time t ₁ . This driving signal, driving device 600 reaches the target speed _{V H} at time _{t 2.} That is, the response time until the target speed _VH is followed is t ₂ −t ₁ .

FIG. 12B shows a change when the user 900 operates the handle 115 or receives an external force from the step BP to shorten (shorten) the WB length. From the state WB length that when WB ₀ of ₍₀ theta is the rotation angle at this time), running in the current velocity _{V 0} associated with theta _0, at time _{t 1,} WB length WB _L (this It is assumed that the rotation angle is reduced to θ _L ). Assuming that the target speed associated with the rotation angle θ _L is V _L , the control unit 200 transmits a drive signal for decelerating to the drive wheel unit 210 from time t ₁ . Here, V _H −V ₀ = V ₀ −V _{L is} assumed. This driving signal, driving device 600 reaches the target speed _{V L} to slow _{t 3} than the time _{t 2.} That is, the response time until the target speed V _L is followed is t ₃ -t ₁ and is longer than t ₂ -t ₁ .

  That is, if the amount of change from the current speed to the target speed is the same, the control unit 200 increases the response time to follow the target speed when lowering the speed than to the response time to follow the target speed when the speed is increased. It is adjusted to do. In other words, the control unit 200 determines that the absolute value of the speed decrease amount per unit time when the speed is reduced is the absolute value of the speed increase amount per unit time when the speed is increased. It is generated so as to be smaller than the value. When the response time is set in this way, the driving force of the rear wheel 102 does not decrease at a stretch, and it can be expected that the step BP can be overcome with a higher probability. Note that how much difference is given to the response time may be set in advance by, for example, a look-up table format so as to change according to the current speed, the difference between the target speed and the current speed, or the like.

  FIG. 13 is a graph showing the response time following the target speed in the second example. For example, the change when the user 900 increases the WB length by operating the handle 115 is the same as in the first example of FIG. 12A, and here, the case where the WB length is shortened (shortened). explain.

When the WB length is shortened to WB _L at time t ₁ , the control unit 200 transmits a drive signal that immediately decelerates from time t ₁ to the drive wheel unit 210 in the first example, but in the second example, the time t 1 A drive signal that is delayed from ₁ by a time t _d and decelerated is transmitted to the drive wheel unit 210. That is, the control unit 200 maintains the current speed V ₀ for a while even when the WB length is shortened to WB _L. Thus, by delaying only when the WB length is shortened, the response time to follow the target speed when the speed is lowered is made longer than the response time to follow the target speed when the speed is raised. Even if the response time is set in this way, the driving force of the rear wheel 102 does not decrease at a stretch, and it can be expected that the step BP can be overcome with a higher probability. The delay time t _d is the current speed, to change depending on the difference between the target speed and the current speed, for example may be set in advance by a look-up table format.

  FIG. 14 is a graph showing the response time following the target speed in the third example. For example, the change when the user 900 increases the WB length by operating the handle 115 is the same as in the first example of FIG. 12A, and here, the case where the WB length is shortened (shortened). explain.

When the WB length is reduced to WB _L at time t ₁ , the control unit 200 gradually decreases the speed continuously from time t ₁ to time t _{3 in the first} example, but in the third example, the current speed V set the interim velocity _{V R} between ₀ and the target speed _{V L,} First to slow down until the provisional speed _{V R.} The decelerated again from _{t 4} between times _{t 1} and _{t 3,} at time _{t 3} is adjusted so as to reach the target speed _{V L.} By thus setting the tentative speed V _R only when the WB length is shorter than the response time to follow the target speed when the speed up, long response time to follow the target speed when decreasing the speed doing. Even if the response time is set in this way, the driving force of the rear wheel 102 does not decrease at a stretch, and it can be expected that the step BP can be overcome with a higher probability.

Provisional velocity V _R, for example, can be set to a speed which internally divides the current velocity V ₀ and the target speed V _L at a constant rate. Or, it may be set a provisional speed V _R for each of the current speed V _0. The time t ₄ can set the time t ₁ and t ₃ to the time obtained by internally dividing at a constant rate. Alternatively, the speed variation amount per unit time from the current speed V ₀ to the provisional speed V _R is, to be equal to the velocity change amount per unit time from the provisional speed V _R to the target velocity V _L, the time t ₄ May be set. However, the time t ₄ is adjusted to a time after the time to reach the provisional speed V _R. By adjusting in this way, it can be a fixed time output a driving force corresponding to at least the provisional speed V _R.

  Next, a fourth embodiment will be described. In the first embodiment and the second embodiment, the traveling device has increased the probability that it can overcome the step BP on the traveling surface by means of an absorption mechanism as hardware, but in this embodiment, as in the third embodiment. Similar effects can be obtained by the control of the control unit 200. Therefore, the hardware configuration, the control block configuration, and the processing flow are the same as those of the traveling device 600 of the third embodiment unless otherwise specified, and differences in control by the control unit 200 will be described below.

FIG. 15 is a graph showing the relationship between the rotation angle θ and the target speed according to the fourth embodiment, and shows the same contents as the relationship between the rotation angle θ and the target speed described with reference to FIG. 6 as the first embodiment. It is a graph. The difference from the graph of FIG. 6 is that even when the rotation angle θ is the minimum angle θ _MIN , the target speed is not 0 but V _i greater than 0 is given. That is, the control unit 200, even when WB length is shortest, continues to transmit a driving signal to the driving wheel unit 210 so that the vehicle travels at a constant speed V _i. By controlling in this way, the rear wheel 102, which is the driving wheel, outputs a driving force corresponding to at least the speed V _i , so that the traveling device 600 can be used even if the WB length is shortened by the external force received from the step BP. If you have a certain height difference, you can get over.

  The travel device 600 is provided with an operation button for setting the speed to 0, and when the user 900 operates the operation button during boarding, the control unit 200 is configured to decelerate and set the speed to 0. May be. In this way, it is only necessary to separately determine control for setting the speed to 0 and appropriately modify the processing flow shown in FIG.

Further, the fourth embodiment has been described based on the relationship of FIG. 6 as the first embodiment, but may be based on the relationship of FIG. If based on the relationship of FIG. 7, for a range of up to the rotation angle theta is theta _MIN or theta less than _1, greater than 0, 5.0 (km / h) may be set smaller target speed .

  Although the embodiments have been described above, the traveling device may be configured by combining the embodiments. For example, a traveling device including both the coil over 116 and the rotary damper 511 may be used. Further, the front wheels and the rear wheels of the traveling device do not have to be wheels, and may be grounding elements such as spherical wheels and crawlers. The power source for driving the drive wheels is not limited to a motor, and may be a gasoline engine or the like.

100, 510, 600 Traveling device, 101 Front wheel, 102 Rear wheel, 103 Axle, 110 Front wheel support member, 111 Front support column, 112 Fork, 115 Handle, 116 Coil over, 120 Rear wheel support member, 121 Rear support column, 122 Main body Part, 131 swivel joint, 132 hinge joint, 133 bias spring, 134 rotation angle sensor, 141 step, 200 control unit, 210 drive wheel unit, 220 vehicle speed sensor, 240 load sensor, 250 memory, 251 conversion table, 511 rotary damper 900 users

Claims (5)

A traveling device that has at least a front wheel and a rear wheel with respect to the traveling direction and that the user rides and travels,
A front wheel support member for rotatably supporting the front wheel;
A rear wheel support member for rotatably supporting the rear wheel;
A drive unit for driving at least one of the front wheel and the rear wheel;
An adjustment mechanism for adjusting a wheel base length of the front wheel and the rear wheel by the user changing a relative position of the front wheel support member and the rear wheel support member;
A measurement unit for measuring a relative position of the front wheel support member and the rear wheel support member;
A control unit that controls the drive unit based on a target speed associated with a measurement result of the measurement unit;
A travel device comprising: an absorption mechanism that absorbs at least a part of the external force so as to reduce a change in relative position between the front wheel support member and the rear wheel support member when an external force is applied to the front wheel from a travel surface. The adjustment mechanism includes a hinge that relatively rotates the front wheel support member and the rear wheel support member;
The measurement unit measures an angle formed by the front wheel support member and the rear wheel support member in the hinge,
The traveling device according to claim 1, wherein the absorbing mechanism includes an elastic member provided between a position where the hinge is provided in the front wheel support member and a position where the front wheel is supported. The adjustment mechanism includes a hinge that relatively rotates the front wheel support member and the rear wheel support member;
The travel device according to claim 1, wherein the absorption mechanism includes a rotation suppression mechanism that suppresses a change in a relative angle between the front wheel support member and the rear wheel support member by the hinge. A traveling device that has at least a front wheel and a rear wheel with respect to the traveling direction and that the user rides and travels,
A front wheel support member for rotatably supporting the front wheel;
A rear wheel support member for rotatably supporting the rear wheel;
A drive unit for driving at least one of the front wheel and the rear wheel;
An adjustment mechanism for adjusting a wheel base length of the front wheel and the rear wheel by the user changing a relative position of the front wheel support member and the rear wheel support member;
A measurement unit for measuring a relative position of the front wheel support member and the rear wheel support member;
A control unit that controls the drive unit based on a target speed associated with a measurement result of the measurement unit;
The target speed is associated so as to increase as the wheelbase length increases,
When the adjustment mechanism is adjusted so that the wheel base length becomes shorter than the response time following the target speed when the adjustment mechanism is adjusted so that the wheel base length becomes longer. A traveling device that increases the response time to follow the target speed. A traveling device that has at least a front wheel and a rear wheel with respect to the traveling direction and that the user rides and travels,
A front wheel support member for rotatably supporting the front wheel;
A rear wheel support member for rotatably supporting the rear wheel;
A drive unit for driving at least one of the front wheel and the rear wheel;
An adjustment mechanism for adjusting a wheel base length of the front wheel and the rear wheel by the user changing a relative position of the front wheel support member and the rear wheel support member;
A measurement unit for measuring a relative position of the front wheel support member and the rear wheel support member;
A control unit that controls the drive unit based on a target speed associated with a measurement result of the measurement unit;
The target speed is associated with the wheel base length so as to increase as the wheel base length becomes longer, and a speed greater than 0 is associated with the shortest wheel base length.

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