JP6971446B2 - Travel control device to prevent mistaken stepping on the accelerator - Google Patents

Description

The present invention relates to a traveling control device for an automobile that prevents a runaway caused by stepping on the accelerator by mistake for a brake in an automobile traveling by using two pedals, an accelerator and a brake.

In recent years, two-pedal type accelerators and brakes have become common in automobiles powered by internal combustion engines such as gasoline engines and diesel engines. This is due to the generalization of multi-speed automatic transmissions and continuously variable transmissions. In addition, the number of electric vehicles powered by motors and hybrid vehicles with motors and internal combustion engines is increasing, but since the operation system of vehicles driven by internal combustion engines is followed, two pedals, accelerator and brake, are common. (Hereinafter, these are referred to as two-pedal type automobiles).

On the other hand, Japan is aging and the absolute number of elderly drivers is increasing. Due to the increase in the number of elderly drivers and the generalization of two-pedal type automobiles, runaway accidents caused by mistaken the accelerator for a brake occur frequently, which has become a social problem. For example, when the car was started slowly, but suddenly a child, dog, or cat jumped out in front of the car, and the accelerator was stepped on with the intention of stepping on the brake in a hurry, causing the car to run away and lead to an accident. Hereinafter, there is case 1). The same applies to the case where the car runs out of control and leads to an accident (hereinafter referred to as case 2) because the accelerator is depressed with the intention of stepping on the brake while the car is being parked in the stop frame in the parking lot of a convenience store.

A conventional manual shifting vehicle (hereinafter referred to as a 3-pedal type vehicle) having three pedals of an accelerator, a brake, and a clutch does not run out of control even if the accelerator is mistaken for a brake and the vehicle is continuously stepped on alone. The reason will be explained below, and the fundamental problems of the two-pedal type automobile will be pointed out. In a 3-pedal car, when you stop, you always step on the clutch with the brake. This is because the engine, which is the prime mover, must be stalled unless it is separated from the tire that stops it, and a person who drives a three-pedal type automobile always unknowingly does it. Therefore, even if you mistakenly step on the accelerator when stopping, the engine is disengaged from the tires by stepping on the clutch, so the engine will just be empty and will not run away. On the other hand, in a two-pedal type automobile, "the accelerator and the brake can be used independently with the same operation", so that a mistake in stepping leads to a runaway.

So far, many running control devices for preventing runaway have been considered. For example, the brake has a patent that utilizes the feature of stepping deeper than the accelerator (Reference 1, Japanese Patent Application Laid-Open No. 2007-170232, Toyota Motor Corporation). In this patent, when the accelerator is depressed deeper than a certain threshold value, it is judged as an erroneous operation and decelerated. In addition, since the human body stiffens (stretches) in an emergency when the brake is suddenly stepped on, there is also a patent that utilizes the feature of pressing the steering wheel or pushing the body into the seat back while applying the brake (Reference 2, Japanese Patent Application Laid-Open No. 2013-233893, Mitsubishi Motors Corporation). In this patent, when the steering wheel is pressed or the accelerator is stepped on while pushing the body into the seat back, it is judged as an erroneous operation and the vehicle is decelerated. As a similar patent, there is a patent in which a pedaling force sensor is provided on the accelerator, and if a pedaling force higher than normal is detected when the accelerator is fully opened, it is judged to be an erroneous operation and decelerated (Reference 3, JP-A-11-278092, Isuzu Motors Ltd.). ..

In all of the above-mentioned conventional examples, when the operation characteristics of a person who steps on the brake are found and the situation is found, it is determined that the operation is erroneous and the prime mover such as an engine is decelerated or stopped. The idea is not to eliminate the erroneous operation of accidentally stepping on the accelerator as a brake, but to take measures when a situation that seems to be an erroneous operation is detected. That is, it does not solve the fundamental problem of the two-pedal type automobile, that "the accelerator and the brake can be used independently with the same operation".

There is a conventional example that solves the fundamental problem of a two-pedal type automobile, "the accelerator and the brake can be used independently with the same operation" (Reference 4, Japanese Patent Application Laid-Open No. 2012-164067). This patent proposes a one-pedal vehicle with an integrated accelerator and brake. This one pedal functions as a brake when stepped on and an accelerator that slides sideways. Therefore, in an emergency or panic, if you press this pedal strongly, it will act as a sudden brake. The normal accelerator operation is performed slowly, and the driver should be aware of it and slide his / her foot sideways. This patent solves the fundamental problem of the accelerator and brake of a two-pedal vehicle because the accelerator operation is changed from the conventional stepping operation to the sideways sliding operation. However, the operation of sliding the accelerator sideways with the foot is a major change in the history of the automobile industry, which has a long history, and has not reached rapid spread.

Problems to be solved by the invention

There is a need for a driving control device for automobiles that eliminates runaway accidents caused by an elderly driver mistakenly stepping on the accelerator for a brake. Reference patents 1 to 3 as a conventional example are proposals for a traveling control device that decelerates or stops the prime mover when a situation presumed to be an erroneous operation is detected in a two-pedal vehicle. It was not an invention that solved the fundamental problem of the same brake operation and prevented erroneous operation. Reference Patent 4 solves the fundamental problem that the accelerator and brake operations of a two-pedal vehicle are the same by introducing the operation of sliding the accelerator sideways with the foot, but the accelerator operation is different from the conventional one. , Has not reached rapid spread. As described above, a vehicle running control device that solves the fundamental problem that the accelerator and brake operations of a two-pedal vehicle are the same while following the conventional accelerator operation has not yet been realized.

JP-A-2007-170232 JP 2013-233893 Japanese Patent Application Laid-Open No. 11-278902 JP 2012-16067

Means to solve problems

The present invention relates to a vehicle traveling control device that solves the fundamental problem that the accelerator and brake operations of a two-pedal vehicle are the same while following the conventional accelerator operation. Instead of detecting the mistake of stepping on the accelerator as a brake, the idea is changed 180 degrees, and the operation of the accelerator is changed within the range that the driver can accept so as not to make a mistake in the operation in the first place.

There are three notable facts to solve the problem. The first is the rapid spread of advanced driver assistance systems (ADAS) for autonomous driving or risk prevention. A typical ADAS mechanism is to recognize surrounding people and objects with a CCD camera or millimeter-wave sensor mounted on an automobile to avoid a collision. When automatic driving by ADAS is set, the vehicle in front is recognized and tracked within the range of the preset maximum speed, and the speed is automatically accelerated / decelerated while maintaining the optimum inter-vehicle distance. At this time, the driver did not operate the accelerator or the brake, and both feet did nothing. However, once the driver steps on the brakes at his / her own will to stop at a traffic light, the next time he / she starts driving, he / she decides whether to start the car by stepping on the normal accelerator or to start again by automatic driving by ADAS. Must instruct. Generally, an ADAS vehicle has a lever or switch near the steering wheel for setting ADAS (maximum speed, inter-vehicle distance, setting / cancellation) (hereinafter referred to as ADAS lever). If the maximum speed and the inter-vehicle distance are set in advance, the ADAS lever can be pulled to start automatic driving in order to start running again with ADAS after stopping once at a traffic light or the like. At this time, the driver starts the car without operating the accelerator or the brake at all. The first fact to note is that with the rapid spread of ADAS, drivers are beginning to use not only the accelerator but also the ADAS lever to start the vehicle.

The next point to be noted is the behavior of the driver immediately before the accelerator is mistaken for a brake.
In Case 1, which is the accident described in [0003], when the driver shifts from the state where the accelerator is loosely stepped on to the state where the brake is stepped on, the right foot temporarily separates from the accelerator that was stepped on, and the accelerator is mistakenly recognized as a brake again. Is stepping on strongly. The second fact to note is that just before the accelerator is mistaken for a brake, the foot is temporarily released from the accelerator.

The third point to be noted is the digitization of automobiles. Conventionally, a unit for operating a vehicle such as a steering wheel, an accelerator, and a brake in the driver's seat has been mechanically connected to the corresponding vehicle equipment. For example, the rotation of the steering wheel was connected to the steering wheel of the front wheel by the gear, the accelerator was connected to the throttle valve that takes in the air of the engine by the wire, and the brake was connected to the disc brake of the wheel by the hydraulic pressure. Recently, the digitization of automobiles is advancing, in which the operation of the steering wheel, accelerator, brake, etc. is electrically read and the control signal is instructed to the motor provided in the corresponding vehicle equipment. It is called drive-by-wire because it is connected by a signal line (electric line, wire). In particular, the accelerator is the most electronic, and the accelerator installed in the vehicle only moves the variable resistor. The resistance value, which indicates the degree of depression of the accelerator, is electrically transmitted to the motor that moves the throttle valve to accelerate or decelerate the prime mover. The third fact to note is that the accelerator is becoming more electronic, and the driving control device can preferentially open and close the throttle valve regardless of the amount of depression of the accelerator by the driver. be.

The present invention in consideration of the above three notable facts will be described below. In the present invention, in an automobile in which driving is operated by two pedals, an accelerator and a brake, a means for detecting a fully closed state of the accelerator, a means for detecting that the automobile is stopped or at a speed equal to or lower than a preset speed, and a driver. Is equipped with a means to release the output restriction of the prime mover by operating a switch or a lever (hereinafter referred to as an accelerator start lever), and the prime mover is triggered by the vehicle stopping or the accelerator being fully closed at a speed below a preset speed. Control to limit the output and operate the prime mover normally if the accelerator is depressed after operating the accelerator start lever even if the vehicle stops or detects that the accelerator is fully closed at a speed below a preset speed. It is characterized by performing.

Hereinafter, an operation example of the present invention will be described with a preset speed of 10 km / h. For example, consider the situation of Case 1 in which an elderly person slowly starts a car, but suddenly a child, a dog, or a cat jumps out in front of the car. When the vehicle is moving forward at a speed of 8 km / h, and when the user takes his / her foot off the accelerator and tries to put his / her foot on the brake, the traveling control device of the present invention states that the speed of 8 km / h is 10 km / h or less, which is preset, and that the foot is from the accelerator. By releasing, the engine output is limited by triggering that the accelerator is temporarily fully closed. Next, even if you mistakenly step on the accelerator for a brake, the engine output is already limited, so a runaway accident will not occur. After calmly stopping the car, when restarting, operate the accelerator start lever and then step on the accelerator that enables normal engine control to restart. At this time, the driver is conscious of stepping on the accelerator and is operating the accelerator start lever, and does not suddenly step on the accelerator.

For example, consider the situation of Case 2 in which a car is parked in a stop frame in a parking lot of a convenience store. When moving backward at 8 km / h, trying to stop at the stop frame, taking the foot off the accelerator, and trying to put the foot on the brake, the traveling control device of the present invention has a speed of 8 km / h which is 10 km / h or less, which is preset. Then, by taking the foot off the accelerator, the engine output is limited by the trigger that the accelerator is temporarily fully closed. Next, even if you mistakenly step on the accelerator for a brake, the engine output is already limited, so a runaway accident will not occur. When restarting to correct the stop position again, operate the accelerator start lever and then step on the accelerator to accelerate the motor. At this time, the driver is conscious of stepping on the accelerator and is operating the accelerator start lever, and does not suddenly step on the accelerator.

When traveling on a general road or a highway at a speed of 50 km / h, the amount of depression of the accelerator is not constant, and acceleration / deceleration is performed by changing the amount of depression. Occasionally, the accelerator may speak once and the vehicle may be running with engine braking. In such a case, the traveling control device according to the present invention detects that the speed is not 10 km / h or less, and can operate normally even if the accelerator is stepped on again after the foot is taken off the accelerator.

Consider a situation where the vehicle stops at a red traffic light, the traffic light turns blue, and the car starts moving. During the stop, the driver is stepping on the brakes or using the parking brake and is off the accelerator. The travel control device of the present invention limits the output of the engine by using a preset stop speed of 10 km / h or less and a fully closed accelerator as a trigger. When the traffic light turns green and the vehicle restarts, the engine output is limited even if you step on the accelerator, so you cannot get on the flow of traffic. Therefore, when restarting, the accelerator start lever is operated to make the engine output normal, and then the accelerator is stepped on to restart. This procedure is different from the accelerator operation in a normal automobile (when stepped on, the prime mover speeds up). However, in an automobile equipped with ADAS, in order to restart automatic driving from a stopped state, it is similar to the fact that it has become common to operate the ADAS lever instead of stepping on the accelerator. Therefore, the accelerator start lever and the ADAS lever according to the present invention can be used in common, and the ADAS and the travel control according to the present invention can be switched in advance as the travel mode. In either mode, when the vehicle is stopped and then restarted, the lever is operated, which does not give the driver a sense of discomfort.

When making a left turn at an intersection, release your foot from the accelerator when going straight and slow down with the brakes. When the speed has slowed down sufficiently, the left turn will start. In such a case, the traveling control device according to the present invention limits the output of the engine by using a preset speed of 10 km / h or less and a fully closed accelerator as a trigger. If you limit the accelerator so that the engine does not react at all, you may stop at the intersection while turning left, but the output of the engine that slowly passes through the intersection is sufficient. After passing the intersection, you need to accelerate and speed up. At this point, after operating the accelerator start lever, the output of the motor can be set to normal, and the accelerator can be stepped on to accelerate the speed of the motor.

When making a right turn at this intersection, when you are going straight, release your foot from the accelerator, slow down with the brakes, and stop until the oncoming vehicle stops coming. In such a case, the traveling control device according to the present invention limits the output of the engine by using a preset speed of 10 km / h or less and a fully closed accelerator as a trigger. If you limit the engine to not react to the accelerator at all, you may get stuck in the middle of the intersection, but the output of the engine slowly passing through the intersection is sufficient. After passing the intersection, you need to accelerate and speed up. At this point, after operating the accelerator start lever, the output of the motor can be set to normal, and the accelerator can be stepped on to accelerate the speed of the motor.

As described above, the present invention is characterized in that the accelerator operation is changed under certain conditions, and the problem of the two-pedal type automobile is fundamentally solved. On the other hand, in addition to the operation of stepping on the accelerator, a new procedure of operating the accelerator start lever is required, but since the operability is similar to that of the rapidly spreading ADAS, there is a merit that it can be accepted in the market without discomfort. The present invention, while following the operation called step on the conventional accelerator, the operation of the 2 pedal vehicle accelerator and brake is that it solves the fundamental problem of the same. In the measures for detecting an erroneous operation represented by References 1 to 3, the state in which the accelerator is erroneously depressed as a brake is detected, whereas in the present invention, the state in which the accelerator is released is detected as a normal operation, resulting in an erroneous operation. The big difference is that the prime mover is controlled before it arrives.

In order to provide this travel control system, three new means are required. However, it does not pose a big problem for realization. The means for detecting the fully closed state of the accelerator can be realized without an additional sensor by reading the output of the digitized accelerator. Next, the means for detecting to or less than the set speed car there et beforehand, if utilizing the vehicle speed sensor attached to any vehicle, can be realized additional sensor without. Finally, the accelerator start lever can also be used as the ADAS lever. It is necessary to add or change the software that controls the engine and motor.

The invention's effect

According to the present invention, the fundamental problem that the accelerator and brake operations of a two-pedal vehicle are the same is solved, and an erroneous operation of stepping on the accelerator as a brake is not caused. In addition, although a procedure different from the normal accelerator operation is required, it is accepted in the market without any discomfort because it has similar operability to the rapidly spreading ADAS.

Travel control device in Example 1 of the present invention (in the case of an internal combustion engine) Travel control device (in the case of an electric motor) according to the second embodiment of the present invention. Travel control flowchart according to the first embodiment of the present invention Travel control flowchart according to the second embodiment of the present invention

1 Accelerator pedal 2 Accelerator pedal sensor 3 Signal line 4 Throttle 5 Engine 6 Injector 7 ECU (engine control unit)
8 Operation lever 9 In-vehicle display unit 10 Vehicle speed sensor 11 Motor

Example 1 according to the present invention will be described. The present embodiment is an automobile using an engine as an internal combustion engine as a prime mover, and is provided with ADAS and a traveling control device according to the present invention in combination, and the operation lever thereof shares the ADAS operation lever and the accelerator start lever. There is. The configuration is shown in FIG. The drive-by-wire accelerator sends the amount of depression as an electric signal to the ECU.
The ECU controls the engine speed by opening and closing the throttle that takes in air and controlling the injector that sends gasoline into the piston according to the amount of depression of the accelerator.
The driver sets one of the three driving modes in advance. When automatic driving by ADAS is selected, the display becomes "automatic". In this ADAS mode, by operating the operation lever, automatic driving that tracks the vehicle in front becomes possible. At this time, the accelerator is not required and only the brake is used. If the brake is stepped on by the driver's intention and the vehicle stops once, the operation lever is operated to restart ADAS the next time the vehicle restarts. If there is a situation in which ADAS cannot respond, such as when another vehicle suddenly interrupts the vehicle in front during automatic driving that tracks the vehicle in front, the driver will be warned as "Yes". To call attention to.
When the traveling control according to the present invention is selected, the display becomes "safe". In this travel control mode, when the accelerator is released at a speed (for example, 10 km / h) or less set in advance, the output of the engine is limited. In this state, the warning is set to "Yes" to alert the driver that the accelerator does not work. Next, even if the accelerator is stepped on, the vehicle cannot be accelerated sufficiently. Therefore, in the case of normal driving, the vehicle is started by stepping on the accelerator after operating the operation lever, as in the case of starting the vehicle tracking running in front of the vehicle with ADAS. Since the driver operates the hands and feet and steps on the accelerator while checking, it does not lead to an erroneous operation in which the accelerator is mistaken for a brake. In the unlikely event that you do not operate the operating lever and mistakenly step on the accelerator for the brake, you will not run out of control.
FIG. 3 shows a flowchart for realizing the traveling control device according to the present invention in the first embodiment. It does not include the procedure for switching ADAS, main driving control, and normal driving mode. When the engine is started, the normal engine output can be controlled by the accelerator. The control program always keeps track of the amount of depression of the accelerator and the vehicle speed, and limits the engine output when the accelerator is fully closed below the preset speed. If the driver operates the operation lever, which is the accelerator start lever, control is performed to return the engine output to the normal level.
When the driver sets the normal driving mode, the display becomes "normal", and neither ADAS nor the driving control according to the present invention is performed, and the engine is controlled only by the accelerator operation by the driver.

Example 2 according to the present invention will be described. Unlike the first embodiment, the second embodiment is an automobile using a motor as a prime mover, and when the accelerator is fully opened in a state where the prime mover output is limited, an emergency stop is performed. The difference from the first embodiment will be described. The configuration is shown in FIG. The drive-by-wire accelerator sends the amount of depression as an electric signal to the ECU. The ECU controls the number of revolutions of the motor according to the amount of depression of the accelerator. According to the traveling control of the present invention, even if the accelerator is mistakenly stepped on as a brake while the output of the motor is limited, it does not lead to a runaway. However, if you accidentally step on the accelerator as a brake, you can forcibly apply the brakes to make an emergency stop, which will increase safety. In the second embodiment, FIG. 4 shows a flowchart for realizing the traveling control device according to the present invention. In addition to FIG. 3 of the flowchart that realizes the traveling control of the first embodiment, a judgment as to whether or not the accelerator is fully opened is added after the output of the motor is limited. In FIG. 4, the accelerator is fully opened to detect the operation of the driver who mistakenly steps on the accelerator as a brake. Instead of fully opening the accelerator, as described in the reference, the accelerator pedaling force and the force with which the waist pushes the seat can also be used.

Claims (1)

In a car that operates with two pedals, the accelerator and the brake, a means for detecting that the speed of the car is below a preset speed, a means for detecting a fully closed state of the accelerator, and a driver operating a switch or a lever. Equipped with a means to lift the output restriction of the prime mover by
The output of the prime mover is limited by triggering that the accelerator is fully closed below the preset speed of the car.
When the above switch or lever is operated after the accelerator is fully closed at a speed lower than the preset speed of the automobile, the output of the prime mover is as usual.

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