JPWO2016121718A1 - Wheelbarrow - Google Patents

Abstract

When the switch (26) is turned on, the control unit (21) confirms whether or not the user (900) is holding the holding unit (4) via the contact sensor (23). When it is determined that the user (900) is gripping the grip portion (4), the control portion (21) executes first control for making the rear wheel (2) faster than the normal speed. Then, the stroller (100) will move at a faster speed than the user (900), and the rear wheel (2) will move to a position away from the user. Since the user (900) is gripping the grip portion (4), the main body portion (10) rotates around the rotation axis (pitch direction) of the rear wheel (2), and the front wheel (1) is separated from the ground plane. Will float.

Description

  The present invention relates to a handcart that includes wheels and rotationally drives the wheels.

  Conventionally, in a wheelbarrow, in order to get over the step, the wheel is lifted around the rear wheel and a wheelie operation is performed over the step.

  For example, in the handcart of Patent Document 1, when the user operates the lever, the rear wheel is moved from the rear position to the front position, and the front wheel can be easily lifted.

JP 2008-80895 A

  However, in the case of a wheelbarrow that rotates and drives wheels by a driving force, compared to the conventional wheelbarrow described in Patent Document 1, the weight increases, and thus there is a problem that a wheelie operation is difficult.

  Moreover, since the state where the front wheel is lifted is a state where only the driving wheel is grounded, the wheelbarrow may move regardless of the intention of the user.

  Accordingly, an object of the present invention is to provide a handcart that assists the wheelie operation while reflecting the intention of the user.

  The wheelbarrow of the present invention includes a main body portion, a rear wheel attached to the main body portion and having a driving force, and a front wheel attached to the front side of the moving direction of the user rather than the rear wheel in the main body portion. A gripping part attached to the main body part, a wheelie operation detection part for detecting an operation of the user trying to lift the front wheel from the grounding surface, and the user gripping the gripping part. A grip detection unit for detecting; and a control unit for controlling driving of the rear wheel.

  The control unit detects that the user is holding the grip unit by the grip detection unit, and the wheelie operation detection unit attempts to float the front wheel of the user from the grounding surface. When an operation to be performed is detected, first control is performed to assist the floating of the front wheel by driving the rear wheel at a speed faster than the current driving speed of the rear wheel.

  In this way, the wheelbarrow drives the rear wheels at a speed higher than the current driving speed when the user is in a state of gripping the gripping portion and the user detects an operation to lift the front wheels. Let Therefore, since the rear wheel moves to a position away from the user, the main body rotates around the rotation axis (pitch direction) of the rear wheel, and the front wheel floats. The operation to be lifted is, for example, when the user presses a switch labeled “Willie switch”, when the user actually lifts the front wheel a little, etc. In addition, when the user actually shifts the front wheel slightly and then shifts to the first control, the “first control” includes performing control that causes the front wheel to float further from a state where the front wheel floats slightly. Thereby, the handcart can assist the wheelie operation while reflecting the intention of the user.

  In addition, the control unit performs the second control that drives the rear wheels at a speed that matches the current speed after the first control, thereby maintaining the wheelie state until the front wheels exceed the step. Is preferred.

  In addition, the control unit performs third control to drive the rear wheel at a speed slower than the current speed when the predetermined condition is satisfied after the second control, so that the wheelie is moved after the front wheel exceeds the step. It is preferable to release the state.

  Note that the handcart preferably includes a step difference detection unit that detects that the front wheel has exceeded the step. In this case, the handcart shifts from the second control to the third control when the front wheel exceeds the step. Further, the handcart may be provided with a step detection unit that detects that the rear wheel is in contact with the step. In this case, when the front wheel comes into contact with the step, the control shifts from the second control to the third control.

  Furthermore, it is preferable that the handcart includes a body posture detection unit that detects whether the front wheel is in contact with the ground or whether the front wheel is floating from the contact surface. In this case, the handcart shifts from the first control to the second control when the front wheel shifts from the grounded state to the floating state.

  The main body posture detection unit can be configured by an inclination sensor that measures the inclination of the main body in the pitch direction, or can be configured by a distance measurement sensor that measures the distance from the ground plane. Is possible.

  Further, the handcart may be provided with an encoder that detects rotation of the front wheels and the rear wheels. Thereby, the handcart can measure the present speed with an encoder. In addition, for example, when the front wheel and the rear wheel have the same rotational speed, the wheelbarrow can be determined to be in a state where the front wheel is grounded, and when the front wheel is idle and the rear wheel is rotating, the wheelie state Can be determined. When it is determined that the wheelbarrow is in the wheelie state, the wheelbarrow shifts from the first control to the second control.

  According to the present invention, the wheelie operation can be assisted while reflecting the user's intention.

FIG. 1A is a side view of a state in which the user pushes the stroller, and FIG. 1B is a front view. It is a hardware block diagram of a stroller. It is the figure which looked at the state which a user pushes a stroller from the side. It is the figure which looked at the state which a user pushes a stroller from the side. It is a flowchart which shows operation | movement of a control part. It is the figure which looked at the state which a user pushes a stroller from the side. It is a hardware block diagram of the stroller according to the first modification. 10 is a flowchart illustrating an operation of a control unit according to Modification 1. It is a hardware block diagram of the stroller according to the second modification. 10 is a flowchart illustrating an operation of a control unit according to Modification 2. FIG. 11A is a hardware block diagram of the stroller according to the third modification, and FIG. 11B is a hardware block diagram of the stroller according to the fourth modification. It is the figure which looked at the state which a user pushes a stroller from the side.

  FIG. 1A is a side view of the user 900 pushing the stroller 100, and FIG. 1B is a front view. FIG. 2 is a hardware block diagram of the stroller 100.

  As shown in FIGS. 1 (A) and 1 (B), the stroller 100 includes a rod-like main body 10 that is long in the vertical direction, and a pair of rear wheels 2 that are rotatably connected to the lower side of the main body 10. And the gripping part 4 connected to the upper side of the main body part 10, the front wheel support part 5 connected to the main body part 10 and extending obliquely forward, and the opposite side of the front wheel support part 5 to which the main body part 10 is connected. A front wheel 1 connected to the side, and a seat portion 8 connected to the main body portion 10 and the front wheel support portion 5 are provided.

  In the present embodiment, an example in which the front wheel 1 is two wheels is shown, but it may be one wheel or three or more wheels. Moreover, although the rear wheel 2 has shown the example which is two wheels in this embodiment, one wheel or three or more wheels may be sufficient.

  Moreover, although the connection part of the main-body part 10 and the front-wheel support part 5 is connected firmly, it is good also as an aspect which slides to the upper side by unlocking, for example, in this case, the front wheel 1 and the rear wheel 2 The stroller 100 is folded by being able to narrow the interval.

  The stroller 100 is an electric wheelbarrow provided with a drive unit 25 that rotationally drives the rear wheel 2. The pair of rear wheels 2 are attached to the same shaft and rotate synchronously. However, it is also possible to individually drive and rotate them.

  A box containing a control unit 21, a battery, and the like is attached to the lower side of the seat 8. In the present embodiment, the front wheel 1 does not have a driving force, but a driving unit that drives the front wheel 1 may be further provided.

  As shown in FIG. 2, the stroller 100 includes a control unit 21, a ROM 22, a contact sensor 23, a RAM 24, a drive unit 25, and a switch 26 as hardware.

  The control unit 21 is a functional unit that comprehensively controls the operation of the stroller 100, and reads out a program stored in the ROM 22 and temporarily stores the program in the RAM 24 to realize various operations.

  The contact sensor 23 is provided in the grip portion 4 and functions as a grip detection portion that detects that the user 900 is gripping the grip portion 4. Further, the contact sensor 23 may have a function of detecting a force with which the user 900 pushes the grip portion 4 in the traveling direction. In this case, the contact sensor 23 includes a piezoelectric element or the like that detects a pressing force against the grip portion 4.

  When the control unit 21 detects that the user 900 is holding the grip unit 4, the control unit 21 calculates a torque for the drive unit 25 to apply to the motor (not shown) according to the force pressing the grip unit 4. . However, the control unit 21 calculates an applied torque at which the moving speed of the stroller 100 in the traveling direction does not exceed a predetermined speed limit. The speed limit is specified to be equal to or less than a general walking speed (for example, 3 km / h). The relationship between the moving speed with respect to the traveling direction and the applied torque is measured in advance and stored in the ROM 22.

  The drive unit 25 is a functional unit that drives a motor that rotates a shaft attached to the rear wheel 2. The torque calculated by the control unit 21 is applied to the motor of the rear wheel 2 to rotate the rear wheel 2. To do.

  Thereby, when the user 900 moves the stroller 100 forward, an applied torque for reducing the force with which the user 900 pushes the stroller 100 is calculated, and the rear wheel 2 is rotationally driven.

  And the control part 21 performs operation | movement which assists wheelie operation, when the user 900 detects operation which tries to lift a front wheel from a ground surface.

  3 and 4 are views of the state where the user 900 presses the stroller 100 during the wheelie operation as seen from the side, and FIG. 5 is a flowchart showing the operation of the control unit 21.

  First, the control unit 21 confirms whether or not the user 900 has detected an operation for lifting the front wheel 1 from the grounding surface. In this example, the control unit 21 checks whether or not the switch 26 is turned on (s11). The switch 26 is provided in the grip portion 4 and functions as a wheelie operation detection portion that detects an operation in which the user 900 attempts to lift the front wheel 1 from the ground surface. For example, “Willie switch” is displayed on the switch 26, and the user 900 can understand that when the switch 26 is pressed, the wheelie operation is assisted. When the switch 26 is pressed, the control unit 21 can determine that the user 900 intends to perform a wheelie operation. Note that the switch 26 is not limited to the example of being attached to the grip portion 4, and may be attached to, for example, a step attached near the rotation shaft of the rear wheel 2 so that the user 900 can press it with his / her foot.

  When the switch 26 is turned on, the control unit 21 confirms whether or not the user 900 is holding the holding unit 4 via the contact sensor 23 (s12). When it is determined that the user 900 is gripping the grip portion 4, the control portion 21 executes the first control for making the rear wheel 2 faster than the normal speed (s13). For example, the control unit 21 calculates the applied torque that is higher by a predetermined ratio (for example, 30%) than the current applied torque and outputs it to the drive unit 25 to drive the rear wheel 2 at a speed faster than the current speed. Let Alternatively, the control unit 21 outputs the applied torque higher than the applied torque corresponding to the walking speed of the general user 900 (for example, 3 km / h), so that the rear wheel 2 is rotated at a speed faster than the current speed. Drive.

  Then, the stroller 100 moves at a speed faster than the moving speed of the user 900, and the rear wheel 2 moves to a position away from the user to the front side. Since the user 900 is gripping the grip portion 4, as shown in FIGS. 3 (A) and 3 (B), the main body portion 10 rotates around the rotation axis (pitch direction) of the rear wheel 2, The front wheel 1 floats from the ground surface. As a result, the stroller 100 enters a wheelie state.

  Thereafter, the control unit 21 checks whether or not a predetermined time (for example, 5 seconds) has elapsed (s14). For example, when 5 seconds have elapsed, the control unit 21 returns the applied torque to the original state, and executes second control for performing processing for returning the rear wheel 2 to the normal speed (s15). Thereby, as shown to FIG. 3 (B) and FIG. 4 (A), the stroller 100 maintains a wheelie state. Therefore, the user 900 can push the stroller 100 in a state where the front wheel 1 is lifted when the switch 26 is turned on to indicate the intention to go over the step.

  In addition, the height of the front wheel 1 in the wheelie state increases as the rotational speed of the rear wheel 2 increases with respect to the normal movement speed or as the time for performing the first control increases. Therefore, for example, a “willy height change button” may be provided on the grip portion 4 so that the user 900 can specify the height of the front wheel 1 in the wheelie state.

  Thereafter, the control unit 21 further confirms whether or not a predetermined time (for example, 30 seconds) has elapsed (s16). For example, when 30 seconds have elapsed, the control unit 21 performs the third control for reducing the applied torque and driving the rear wheel 2 at a speed lower than the current speed (moving speed of the pedestrian) ( s17). Therefore, the rear wheel 2 approaches the user's position. Since the user 900 is gripping the grip portion 4, as shown in FIGS. 4 (A) and 4 (B), as shown in FIGS. 3 (A) and 3 (B), the rear wheel 2 The main body 10 rotates about the rotation axis (pitch direction), and the front wheel 1 contacts the grounding surface. As a result, the stroller 100 is released from the wheelie state.

  Finally, the control unit 21 checks whether or not a predetermined time (for example, 5 seconds) has passed (s18), and when 5 seconds have passed, the applied torque is returned to the original state, and the rear wheel 2 is moved. Processing to return to the normal speed is performed (s19).

  However, the processing after s17 is not essential. For example, in the wheelie state as shown in FIG. 6A, when the rear wheel 2 comes into contact with the step, the rotational speed of the rear wheel 2 decreases. Therefore, the main body 10 rotates about the rotation axis (pitch direction) of the rear wheel 2, and the front wheel 1 comes in contact with the grounding surface as shown in FIG. 6B. In this manner, the stroller 100 is released from the wheelie state. Therefore, the predetermined time in s16 is preferably set to be long to some extent until the front wheel 1 reliably exceeds the step.

  Next, FIG. 7 is a block diagram illustrating a hardware configuration of the stroller 100A according to the first modification. The same components as those in the stroller 100 shown in FIG.

  A stroller 100 </ b> A according to the first modification includes a rear wheel encoder 32. The rear wheel encoder 32 detects the rotation angle of the rear wheel 2 and outputs the detection result to the control unit 21. The control unit 21 can calculate the rotational speed or rotational acceleration of the rear wheel 2 from the rotational angle input from the rear wheel encoder 32. Further, the control unit 21 can calculate the distance traveled by the stroller 100 </ b> A from the rotation angle input from the rear wheel encoder 32.

  FIG. 8 is a flowchart showing the operation of the control unit 21 in the stroller 100A. Processes that are the same as those in the flowchart shown in FIG.

  In the stroller 100A, the control unit 21 determines whether the stroller 100A has moved a predetermined distance (for example, 1 m) after making the rear wheel 2 faster than the normal speed in the process of s13 (s24). That is, the stroller 100A according to the modification 2 determines whether or not the vehicle has shifted to the wheelie state based on the movement distance calculated based on the rotation angle input from the rear wheel encoder 32 instead of the elapsed time.

  Similarly, the control unit 21 determines whether or not the stroller 100A has moved a predetermined distance (for example, 1 m) even after the rear wheel 2 is returned to the normal speed in the process of s15 (s26). That is, the stroller 100A determines whether or not the front wheel 1 has exceeded the step based on the travel distance, not the elapsed time.

  Further, the control unit 21 determines whether or not the stroller 100A has moved a predetermined distance (for example, 1 m) even after the rear wheel 2 is made slower than the normal speed in the process of s17 (s28). That is, the stroller 100A determines whether or not the front wheel 1 is grounded and returns to the normal state based on the travel distance, not the elapsed time.

  In the stroller 100A according to the modified example 2, the control unit 21 can also calculate the torque that the drive unit 25 applies to the motor (not shown) according to the rotational speed or rotational acceleration of the rear wheel 2. is there. Therefore, in the stroller 100A according to the second modification, the contact sensor 23 does not necessarily have a function of detecting the force with which the user 900 pushes the grip portion 4 in the traveling direction. Even in this case, the control unit 21 calculates the applied torque so that the moving speed of the stroller 100A does not exceed the limit speed (for example, 3 km / h).

  Further, in the stroller 100A according to the modified example 2, the control unit 21 can obtain the speed of the pedestrian from the rotation angle of the rear wheel 2, and can obtain the current speed of the stroller 100A. For example, the control unit 21 obtains an average value of moving speeds obtained from the rotation angle of the rear wheel 2 (an average value of the same speeds in the past 60 seconds) and sets the average value as the current speed of the stroller 100A.

  Next, FIG. 9A is a block diagram illustrating a hardware configuration of the stroller 100B according to the second modification. The same components as those in the stroller 100 shown in FIG.

  A stroller 100 </ b> B according to the second modification includes an inclination sensor 35. The inclination sensor 35 corresponds to a main body posture detection unit, and detects an inclination angle of the main body unit 10 in the pitch direction with respect to the horizontal direction. The control unit 21 determines that the front wheel 1 has floated and the user 900 has performed an operation to float the front wheel 1 when the inclination angle of the main body unit 10 is equal to or greater than a predetermined angle (for example, 5 degrees). In the case of the second modification, the “first control” includes performing control to raise the front wheel further from a slightly floating state.

  FIG. 10 is a flowchart showing the operation of the control unit 21 in the stroller 100B. Processes that are the same as those in the flowchart shown in FIG.

  In the stroller 100B, instead of checking whether the switch 26 is turned on, the control unit 21 determines whether the user 900 determines whether the inclination angle of the main body unit 10 is a predetermined angle (for example, 5 degrees) or more. It is confirmed whether or not an operation for floating the front wheel 1 has been performed (s31). However, when the inclination angle of the main body 10 is increased, there is a possibility that the main body 10 is an uphill. Therefore, also in the stroller 100B, the control unit 21 confirms whether or not the switch 26 is turned on, and the user 900 You may make it confirm whether operation which tried to lift the front wheel 1 was performed.

  Further, the control unit 21 in the stroller 100B confirms whether or not the stroller 100B has shifted to the wheelie state after the rear wheel 2 is made faster than the normal speed in the process of s13 (s34). For example, when the inclination angle of the main body 10 becomes 15 degrees, the control unit 21 determines that the state has shifted to the wheelie state.

  Further, the control unit 21 in the stroller 100B confirms whether or not the front wheel 1 has exceeded a step after returning the rear wheel 2 to the normal speed in the process of s15 (s36). As shown in FIGS. 6 (A) and 6 (B), when the rear wheel 2 comes into contact with the step, the rotational speed of the rear wheel 2 decreases, so that the main body 10 rotates around the rotational axis of the rear wheel 2 ( Rotating in the pitch direction), the inclination angle becomes smaller. Therefore, the control unit 21 determines that the rear wheel 2 is in contact with the step and the front wheel 1 has exceeded the step when the inclination angle of the main body unit 10 becomes a predetermined angle (for example, less than 10 degrees). Thereby, the control part 21 implement | achieves the function of a level | step difference detection part.

  In s36, a contact sensor (contact detection unit) is provided on the rear wheel 2, and whether or not the front wheel 1 has exceeded the step is detected by detecting whether or not the rear wheel has contacted the step through the contact sensor. May be determined. In this case, a step difference detection unit is realized by the contact sensor and the control unit 21 provided on the rear wheel 2.

  In addition, the control unit 21 confirms whether or not the stroller 100B has changed to the normal posture after the rear wheel 2 is made slower than the normal speed in the process of s17 (s38). The normal posture is, for example, a case where the inclination angle of the main body 10 changes from an angle greater than 5 degrees to less than 5 degrees. However, as described above, when the rear wheel 2 comes into contact with the step, the main body portion 10 rotates around the rotation axis (pitch direction) of the rear wheel 2 and the front wheel 1 contacts the ground plane. Therefore, the determination at s36 and the determination at s38 are performed almost simultaneously.

  Note that the main body posture detection unit is not limited to the tilt sensor shown in FIG. 9, and the following modifications are also possible.

  FIG. 11A is a block diagram illustrating a hardware configuration of a stroller 100C according to the third modification. The same components as those of the stroller 100B shown in FIG.

  A stroller 100 </ b> C according to Modification 3 includes a distance measuring sensor 36 instead of the inclination sensor 35. As shown in FIGS. 12A and 12B, the distance measuring sensor 36 is provided at a position near the front wheel 1 in the front wheel support portion 5. The distance measuring sensor 36 measures the distance from the ground plane.

  When the front wheel 1 floats from the grounding surface and the posture of the stroller 100C changes, the distance between the front wheel 1 and the grounding surface changes. Therefore, the control unit 21 can determine the posture of the stroller 100 </ b> C according to the distance from the ground plane detected via the distance measuring sensor 36.

  In the determination of s34, the control unit 21 determines that the stroller 100C has shifted to the wheelie state when the distance from the ground contact surface detected via the distance measuring sensor 36 is equal to or greater than a predetermined value (for example, 10 cm). Also in the case of the modified example 3, the “first control” includes performing control to raise the front wheel further from a slightly floating state. In addition, in the determination of s36, the control unit 21 determines that the front wheel 1 is turned off when the distance to the ground contact surface detected via the distance measuring sensor 36 is greater than a predetermined value (for example, 5 cm) and less than a predetermined value. Judge that the level difference has been exceeded. That is, the distance measuring sensor 36 functions as a step difference detection unit in the process of s36.

  Further, in the determination of s38, when the distance from the ground contact surface detected via the distance measuring sensor 36 is substantially zero, the control unit 21 contacts the ground contact surface and changes to the normal posture. Judge.

  Next, FIG. 11B is a block diagram illustrating a hardware configuration of a stroller 100D according to the fourth modification. The same components as those of the stroller 100B shown in FIG.

  The stroller 100D includes a rear wheel encoder 32 and a front wheel encoder 33.

  The front wheel encoder 33 detects the rotation angle of the front wheel 1 and outputs the detection result to the control unit 21. The control unit 21 can calculate the rotation speed or the rotation acceleration of the front wheel 1 from the rotation angle input from the front wheel encoder 33.

  In this example, the control unit 21 detects the posture of the stroller 100D from the difference between the rotation angle of the front wheel 1 and the rotation angle of the rear wheel 2. Further, the control unit 21 determines that the rear wheel 2 comes into contact with the step due to the difference between the rotation speed of the rear wheel 2 predicted with respect to the applied torque and the actual rotation speed obtained from the detection result of the rear wheel encoder 32. Judge whether or not.

  For example, in the determination shown in s31 of FIG. 10, the control unit 21 determines that the moving speed of the stroller 100D calculated from the rotation angle of the front wheel 1 and the moving speed of the stroller 100D calculated from the rotation angle of the rear wheel 2 are: If the difference is more than a predetermined value, it is determined that the front wheel 1 is in a floating state, and it is determined that the user 900 is performing an action to lift the front wheel 1.

  Further, in the determination of s34, the control unit 21 determines that the rotation speed of the rear wheel 2 predicted for the applied torque is substantially the same as the actual rotation speed obtained from the detection result of the rear wheel encoder 32, When the rotation of the front wheel 1 is stopped (or lower than the predetermined rotation speed), it is determined that the wheely state has been entered. Also in the case of the modified example 4, the “first control” includes performing control to raise the front wheel further from a state where the front wheel is slightly lifted.

  Further, in the determination of s36, the control unit 21 determines that the difference between the rotation speed of the rear wheel 2 predicted for the applied torque and the actual rotation speed obtained from the detection result of the rear wheel encoder 32 is equal to or greater than a predetermined value. When the rotation of the front wheel 1 is stopped (or lower than the predetermined rotation speed), it is determined that the rear wheel 2 is in contact with the step and the front wheel 1 is in a state beyond the step.

  Furthermore, in the determination of s38, the control unit 21 determines that the rotation speed of the rear wheel 2 predicted with respect to the applied torque is substantially the same as the actual rotation speed obtained from the detection result of the rear wheel encoder 32. When the moving speed of the stroller 100D calculated from the rotation angle of the front wheel 1 and the moving speed of the stroller 100D calculated from the rotation angle of the rear wheel 2 are substantially the same, the front wheel 1 comes in contact with the ground surface and is normal. Judge that the posture has changed.

  As described above, the control unit 21 can also detect the posture of the stroller 100D using the rear wheel encoder 32 and the front wheel encoder 33.

  In the present embodiment, an example has been shown in which the switch 900 detects an operation in which the user 900 tries to lift the front wheel 1. However, for example, a front wheel contact sensor is used to determine whether the front wheel 1 is grounded. By doing so, it is also possible to detect an operation of the user 900 trying to lift the front wheel 1. When the state in which the front wheel 1 is floating continues for a predetermined time (for example, 1 second), the control unit 21 determines that the user 900 is performing an operation to lift the front wheel 1.

  Also, if the stroller is equipped with a front wheel encoder and a rear wheel encoder, confirm whether the front wheel 1 is floating by detecting the difference in rotation angle between the front wheel encoder and the rear wheel encoder. can do.

  Various modifications shown in this embodiment can be combined as appropriate. For example, the control unit 21 determines whether or not the user 900 has performed an operation to lift the front wheel 1 by checking whether or not the switch 26 is turned on. When the inclination angle of the main body 10 detected via the sensor 35 is equal to or greater than a predetermined value and the rotation of the front wheel 1 is stopped (or lower than the predetermined rotation speed), it is determined that the wheely state has been entered. To do. In addition, the control unit 21 determines that the rotation speed of the rear wheel 2 predicted with respect to the applied torque is substantially the same as the actual rotation speed obtained from the detection result of the rear wheel encoder 32, and the rotation of the front wheel 1. When the moving speed of the stroller 100D calculated from the angle and the moving speed of the stroller 100D calculated from the rotation angle of the rear wheel 2 are substantially the same, the front wheel 1 touches the ground surface and changes to a normal posture. to decide.

  In the present embodiment, a stroller is shown as an example of the handcart. However, the present invention can be applied to various handcarts such as a shopping cart, a cart, a wheelchair, and a walking assist vehicle such as a silver car. Is possible.

DESCRIPTION OF SYMBOLS 1 ... Front wheel 2 ... Rear wheel 4 ... Grasp part 5 ... Front wheel support part 8 ... Seat part 10 ... Main-body part 21 ... Control part 22 ... ROM
23 ... Contact sensor 24 ... RAM
25 ... Drive unit 26 ... Switch 32 ... Rear wheel encoder 33 ... Front wheel encoder 35 ... Tilt sensor 36 ... Ranging sensors 100, 100A, 100B, 100C, 100D ... Stroller 900 ... User

Claims (10)

The main body,
A rear wheel attached to the main body and having a driving force;
In the main body, a front wheel attached to the front side of the user's traveling direction from the rear wheel,
A gripping part attached to the body part;
A wheelie operation detector that detects an operation of a user trying to lift the front wheel off the ground surface;
A grip detection unit for detecting that the user is gripping the grip unit;
A control unit for controlling the driving of the rear wheel;
With
The control unit detects that the user is holding the grip unit by the grip detection unit, and the wheelie operation detection unit performs an operation to float the front wheel of the user from the grounding surface. A handcart that performs first control for assisting in floating the front wheel by driving the rear wheel at a speed faster than a current driving speed of the rear wheel when the vehicle is detected.   2. The handcart according to claim 1, wherein, after the first control, the control unit performs a second control for driving the rear wheel at a speed in accordance with the current driving speed of the rear wheel.   The control unit according to claim 2, wherein after the second control, when a predetermined condition is satisfied, the control unit performs third control for driving the rear wheel at a speed slower than the current driving speed of the rear wheel. The described wheelbarrow.   The handcart according to any one of claims 1 to 3, further comprising a step difference detection unit that detects that the front wheel has exceeded a step.   The handcart according to claim 4, wherein the step difference detection unit includes a contact detection unit that detects that the rear wheel contacts the step.   The handcart according to any one of claims 1 to 5, further comprising a main body posture detection unit that detects whether the front wheel is in contact with the ground or whether the front wheel is floating from the ground contact surface.   The handcart according to claim 6, wherein the main body posture detection unit includes an inclination sensor that measures an inclination of the main body in the pitch direction.   The handcart according to claim 6, wherein the main body posture detection unit includes a distance measuring sensor that measures a distance from the ground surface.   The handcart according to any one of claims 1 to 8, further comprising an encoder that detects rotation of the front wheel and the rear wheel.   The handcart according to any one of claims 1 to 9, wherein the front wheel has no driving force.

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