Vehicle control device

Abstract

To provide a vehicle control device capable of improving the step-climbing performance of a vehicle.SOLUTION: A vehicle control device includes a control unit. When the control unit determines that the vehicle has come into contact with a road surface step due to a sudden stop of the vehicle, it controls the timing for outputting drive force according to a swinging state of a movable mount, which is provided on the vehicle and swings in the longitudinal direction of the vehicle, and according to an elapsed time from the time of contact.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle control device. [Background technology]

[0002] Patent Document 1 discloses a small mobility vehicle for transporting luggage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-64238 Summary of the Invention [Problem to be solved by the invention]

[0004] In small mobility vehicles, the output of the drive source (for example, a motor) and the wheel diameter are small, making it difficult to improve the ability to overcome obstacles (hereinafter referred to as "advanced obstacle-surmounting performance").

[0005] The present disclosure has been made in consideration of the above, and aims to provide a vehicle control device that can improve the vehicle's ability to overcome obstacles. [Means for solving the problem]

[0006] The vehicle control device according to the present disclosure includes a control unit, and when the control unit determines that the vehicle has come into contact with a bump in the road surface due to a sudden stop, it controls the timing of outputting driving force according to the swing state of a movable platform provided on the vehicle that swings in the fore-and-aft direction of the vehicle and the elapsed time since the vehicle came into contact. [Effects of the Invention]

[0007] According to the present disclosure, the step-over performance of a vehicle can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a vehicle to which a vehicle control device according to an embodiment is applied. [Figure 2] FIG. 2 is a schematic diagram showing a state of the pedestal when the front wheels of the vehicle collide with a step in the vehicle control device according to the embodiment. [Figure 3] FIG. 3 is a schematic diagram showing a state in which the pedestal swings backward after the front wheels of the vehicle collide with a step in the vehicle control device according to the embodiment. [Figure 4] FIG. 4 is a schematic diagram showing the state of the pedestal when the front wheels of the vehicle go over a step and the rear wheels of the vehicle collide with a step in the vehicle control device according to the embodiment. [Figure 5] FIG. 5 is a graph showing the relationship between (a) vehicle speed, (b) pendulum angle of the pedestal, and (c) current of the drive motor when the vehicle goes over a step in the vehicle control device according to the embodiment. [Figure 6] FIG. 6 is a schematic diagram showing a first modification of a vehicle to which a vehicle control device according to an embodiment is applied. [Figure 7] FIG. 7 is a schematic diagram showing a second modified example of a vehicle to which a vehicle control device according to an embodiment is applied. DETAILED DESCRIPTION OF THE INVENTION

[0009] A vehicle control device according to an embodiment of the present disclosure will be described with reference to the drawings. Note that components in the following embodiments include those that are easily replaceable by those skilled in the art, or those that are substantially the same.

[0010] The configuration of a vehicle control device according to an embodiment will be described with reference to Fig. 1. The vehicle control device according to the embodiment is for controlling the traveling of a vehicle that transports luggage indoors or outdoors. Examples of vehicles to which the vehicle control device according to the embodiment is applied include small mobility vehicles that travel autonomously along predetermined routes and small mobility vehicles that travel by remote control.

[0011] A vehicle 1 to which the vehicle control device according to the embodiment is applied includes a vehicle body 11, a mount 12, front wheels 13, rear wheels 14, and a control unit 15, as shown in FIG.

[0012] A platform 12 is attached to the vehicle body 11. The platform 12 is a movable platform that swings like a pendulum in the front-to-rear direction of the vehicle 1. The platform 12 carries cargo to be transported. Front wheels 13 and rear wheels 14 are driven by a drive motor (not shown) mounted on the vehicle 1.

[0013] The control unit 15 is an electronic control unit (ECU) whose main components are a microcomputer including, for example, a central processing unit (CPU), a read-only memory (ROM), a random access memory (RAM), etc. The control unit 15 executes various programs to comprehensively control the operations of various components of the vehicle 1.

[0014] The control unit 15 controls the driving force of the drive motor according to the road surface conditions. For example, when the vehicle 1 suddenly stops, the control unit 15 determines that the vehicle 1 has come into contact with (collided with) a step on the road surface. Then, when the control unit 15 determines that the vehicle 1 has come into contact with a step, it controls the timing of outputting the driving force according to the swing state of the cradle 12 and the time elapsed since the vehicle 1 came into contact.

[0015] For example, consider a case where vehicle 1 is traveling toward the left side of the paper, as shown in Fig. 1. In this case, if front wheel 13 of vehicle 1 comes into contact with a step in the road surface and suddenly stops, as shown in Fig. 2, control unit 15 determines that vehicle 1 has come into contact with the step. When front wheel 13 of vehicle 1 comes into contact with the step, frame 12 begins to swing in a pendulum motion due to inertia.

[0016] In Fig. 2, the platform 12 carrying the load is located at the front of the vehicle 1, so the center of gravity is biased toward the front of the vehicle 1. In other words, the front wheels 13 that are going over the step are heavier, so at this moment the driving force required to go over the step increases, and power consumption also increases. Therefore, when the front wheels 13 of the vehicle 1 come into contact with the step and the platform 12 is located at the front as shown in Fig. 2, the control unit 15 does not output driving force from the drive motor.

[0017] When a predetermined time has passed from the position shown in FIG. 2, the platform 12 carrying the load moves to the rear of the vehicle 1, as shown in FIG. 3, for example, and the center of gravity shifts to the rear of the vehicle 1. In other words, since the front wheels 13 that go over the step are lighter, the driving force required to go over the step at this moment is smaller, and power consumption is also reduced. Therefore, when the platform 12 is positioned at the rear as shown in FIG. 3, the control unit 15 outputs driving force from the drive motor. This allows the front wheels 13 of the vehicle 1 to go over the step.

[0018] When the front wheels 13 of the vehicle 3 go over the step, the rear wheels 14 will then come into contact with the step, as shown in Figure 4. In this case, when the rear wheels 14 of the vehicle 1 come into contact with the step on the road surface and suddenly stop, the control unit 15 determines that the vehicle 1 has come into contact with the step. When the rear wheels 14 of the vehicle 1 come into contact with the step, the frame 12 starts to swing in a pendulum motion due to inertia.

[0019] In FIG. 4, the platform 12 carrying the load is located at the front of the vehicle 1, so the center of gravity is biased toward the front of the vehicle 1. In other words, the rear wheels 14 that are going over the step are lighter, so at this moment the driving force required to go over the step is smaller, and power consumption is also reduced. Therefore, when the rear wheels 14 of the vehicle 1 come into contact with the step and the platform 12 is located at the front as shown in FIG. 4, the control unit 15 outputs driving force from the drive motor. This allows the rear wheels 14 of the vehicle 1 to go over the step.

[0020] It is known that the period of pendulum motion is expressed by the following formula (1): In the formula (1), l is the length of the pendulum arm, and g is the gravitational acceleration.

[0021]

number

[0022] As shown in the above formula (1), the period of the pendulum motion is independent of the mass of the luggage loaded on the cradle 12. Therefore, the time required from when the front wheels 13 of the vehicle 1 come into contact with the step until the cradle 12 reaches the state shown in FIG. 2 is expressed as "T / 4". Also, the time required from when the front wheels 13 of the vehicle 1 come into contact with the step until the cradle 12 reaches the state shown in FIG. 3 is expressed as "3T / 4". Also, the time required from when the rear wheels 14 of the vehicle 1 come into contact with the step until the cradle 12 reaches the state shown in FIG. 4 is also expressed as "T / 4".

[0023] Therefore, the control unit 15 controls the drive motor to output drive force at "T / 4" and "3T / 4" timings after the front wheel 13 of the vehicle 1 contacts the step (after contact is detected). The control unit 15 also controls the drive motor to output drive force at "T / 4" timing after the rear wheel 14 of the vehicle 1 contacts the step. This allows the vehicle 1 to easily overcome the step with minimal drive force and minimal power consumption. Even if the "T / 4" timing is missed, a similar effect can be achieved, for example, at "5T / 4" timing. That is, the control unit 15 controls the drive motor to output drive force at 1 / 4, 3 / 4, and 5 / 4 times the period of the pendulum motion. By performing the above-described control, the step-over performance of the vehicle 1 can be improved even if the vehicle 1 is equipped with a small drive motor.

[0024] Here, Figure 5 shows the relationship between (a) the vehicle speed of the vehicle 1, (b) the pendulum angle of the base 12, and (c) the current of the drive motor when the vehicle 1 goes over a step in the vehicle control device of the embodiment.

[0025] When the front wheels 13 of the vehicle 1 collide with the step, the frame 12 starts to swing in a pendulum motion due to inertia (see FIG. 5(b)). In this case, the control unit 15 temporarily reduces the current to the drive motor because the vehicle speed has decreased due to the collision with the step (see FIG. 5(c)). Then, T / 4 after the collision, the control unit 15 supplies a current to the drive motor to allow the vehicle to climb over the step (see FIG. 5(c)). If the rear wheels 14 of the vehicle 1 have collided with the step, the rear wheels 14 will have completed climbing over the step at this timing.

[0026] Subsequently, 3T / 4 after the collision, the control unit 15 supplies a current to the drive motor to allow the vehicle 1 to climb over the step (see (c) of FIG. 5). As a result, the front wheels 13 complete climbing over the step, and the vehicle 1 resumes traveling (see (a) of FIG. 5).

[0027] When the vehicle collides with a step, an impact load is applied from the front wheels 13 and rear wheels 14, but in the vehicle control device according to the embodiment, part of the kinetic energy of the vehicle body 11 (the luggage portion) continues to move. This leads to mitigation of the impact load, and is also useful for reducing the load on the vehicle body 11 and protecting the luggage.

[0028] (Variation 1) The vehicle control device according to the embodiment is not limited to vehicle 1, and can also be applied to, for example, vehicle 1A as shown in Fig. 6. Vehicle 1A includes a vehicle body 11, a platform 12, front wheels 13, rear wheels 14, a control unit 15, and a plurality of rollers 16. The configuration of vehicle 1A is the same as that of vehicle 1 except for rollers 16.

[0029] The rollers 16 are used to cause the platform 12 to perform a pendulum motion. The platform 12, which has a curved bottom surface, is placed on the rollers 16. As a result, when the vehicle 1A comes into contact with a step, the platform 12 moves on the rollers 16 by inertia, performing a pendulum motion. Even in the vehicle 1A having such a configuration, the control unit 15 performs control as shown in Fig. 5, making it possible for the vehicle 1A to easily overcome the step with minimum driving force and minimum power consumption.

[0030] (Variation 2) The vehicle control device according to the embodiment is not limited to vehicle 1, and can also be applied to, for example, vehicle 1B as shown in Fig. 7. Vehicle 1B includes a vehicle body 11, a frame 12, front wheels 13, rear wheels 14, a control unit 15, a plurality of rollers 16, and a plurality of springs 17. The configuration of vehicle 1B is the same as that of vehicle 1, except for rollers 16 and springs 17.

[0031] Rollers 16 and springs 17 are used to cause platform 12 to perform pendulum motion. Platform 12, which has a flat bottom, is placed on rollers 16. Expandable springs 17 are attached between the front and rear of platform 12 and vehicle body 11. As a result, when vehicle 1B comes into contact with a step, platform 12 moves on rollers 16 by inertia, performing pendulum motion. Vehicle 1B having such a configuration can also easily overcome the step with minimum driving force and minimum power consumption by having control unit 15 perform control as shown in FIG. 5.

[0032] In addition, in Figs. 1, 6 and 7, the vehicles 1, 1A, 1B are shown to be performing movements equivalent to pendulum motion due to inertia, but it is of course possible to realize these movements by means of actuators or the like.

[0033] In the vehicle control device according to the embodiment described above, luggage to be loaded onto the vehicles 1, 1A, 1B is placed on the platform 12 that performs pendulum motion in the fore-and-aft direction of the vehicles 1, 1A, 1B. When the vehicles 1, 1A, 1B suddenly stop due to an external force, it is determined that they have collided with a step or the like, and the timing at which the platform 12 is at the front or rear end is determined based on the time from that point, and driving force is output from the drive motor at the exact moment when the platform 12 reaches the front or rear end.

[0034] In the vehicle control device according to the embodiment, the step-over-step performance of the vehicle 1 can be improved by outputting driving force from the drive motor the moment the front and rear centers of gravity become lighter. Also, by not flowing current at a time when the possibility of overtaking is low, it is possible to suppress temperature rise in the drive motor. Furthermore, in the vehicle control device according to the embodiment, since the mass of the luggage is on the pedestal 12, it is possible to mitigate the impact load on the luggage in the event of a collision.

[0035] Further advantages and modifications will readily occur to those skilled in the art. Thus, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0036] 1 vehicle 11 Body 12 Mounting stand 13 Front wheel 14 rear wheels 15 Control Unit 16 Laura 17 Spring

Claims

[Claim 1] A control unit is provided, The control unit When it is determined that the vehicle has come into contact with a bump in the road surface due to a sudden stop, the timing of outputting a driving force is controlled in accordance with the swing state of a movable platform that is provided on the vehicle and swings in the front-rear direction of the vehicle, and the elapsed time since the vehicle came into contact with a bump. Vehicle control device.

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