Patent Description:
As a conventional technique related to a straddle-type vehicle, a technique of assisting with a rider's operation is available. For example, a rider-assistance system is disclosed in PTL <NUM>. The rider-assistance system warns the rider of the straddle-type vehicle that the straddle-type vehicle inappropriately approaches an obstacle by using a surrounding environment detector that detects the obstacle present in a travel direction or substantially in the travel direction. PTL <NUM> provides a motorcycle comprising a frame mounted on wheels and has a front part and a rear part, a handlebar being located at the front part, means being provided to detect at least the speed and roll angle of the motorcycle when in movement, the frame having a longitudinal median plane (W) joining such front part and the rear part. PTL <NUM> provides a vehicle collision prevention apparatus that activates an automatic brake on the basis of the likelihood of a collision between a host vehicle and a frontward obstruction.

The rider operates the straddle-type vehicle while straddling and being seated on a vehicle body under a situation where a rearview mirror is not provided (that is, a situation where the rider cannot easily recognize what exists right behind the rider). Thus, necessity of assistance operation for the rider regarding a collision by a following vehicle is high. In addition, there is a high probability that the assistance operation is executed in a situation where the rider does not pay attention. Thus, the necessity of the assistance operation has to be determined with high reliability.

The present invention has been made with the above-described problem as the background and therefore obtains a processor and a processing method capable of improving a rider's safety. The present invention also obtains a rider-assistance system that includes the processor. The present invention further obtains a straddle-type vehicle that includes the rider-assistance system.

A processor according to the present invention is a processor for a rider-assistance system of a straddle-type vehicle, as defined by independent claim <NUM>. The processor includes: an acquisition section that acquires surrounding environment information about the straddle-type vehicle; a determination section that determines necessity of assistance operation executed by the rider-assistance system to assist with a rider's operation on the basis of the surrounding environment information acquired by the acquisition section; and a control section that outputs a control command to an execution device to execute the assistance operation in the case where the determination section determines that the assistance operation is necessary. The surrounding environment information includes information on surrounding environment behind the straddle-type vehicle. The surrounding environment information is information corresponding to output of a surrounding environment detector provided to the straddle-type vehicle. The determination section determines the necessity of the assistance operation by using: a collision index value that is an index value depending on the information on the surrounding environment at the rear and is an index value of a collision possibility of a following vehicle against the traveling straddle-type vehicle, wherein the collision possibility becomes higher as the collision index value is increased; and a stability index value that is an index value depending on the information on the surrounding environment at the rear and is an index value of a stability degree of a relative distance of the following vehicle to the traveling straddle-type vehicle. The stability degree of the relative distance becomes higher as the stability index value is increased. The determination section is configured to determine that the assistance operation is necessary in the case where the collision index value is an index value with the higher collision possibility than a determination criterion and the stability index value is an index value with the higher stability degree than a determination criterion.

A rider-assistance system according to the present invention includes the processor.

A straddle-type vehicle according to the present invention includes the rider-assistance system.

A processing method according to the present invention is a processing method for a rider-assistance system of a straddle-type vehicle, as defined by independent claim <NUM>. The method includes: an acquisition step of acquiring surrounding environment information about the straddle-type vehicle by an acquisition section of a processor for the rider-assistance system; a determination step of determining necessity of assistance operation, which is executed by the rider-assistance system, by a determination section of the processor to assist with a rider's operation on the basis of the surrounding environment information acquired by the acquisition section; and a control step of outputting a control command to an execution device to execute the assistance operation by a control section of the processor in the case where the determination section determines that the assistance operation is necessary. The surrounding environment information includes information on surrounding environment behind the straddle-type vehicle. The surrounding environment information is information corresponding to output of a surrounding environment detector provided to the straddle-type vehicle. In the determination step, the determination section determines the necessity of the assistance operation by using: a collision index value that is an index value depending on the information on the surrounding environment at the rear and is an index value of a collision possibility of a following vehicle against the traveling straddle-type vehicle, wherein the collision possibility becomes higher as the collision index value is increased; and a stability index value that is an index value depending on the information on the surrounding environment at the rear and is an index value of a stability degree of a relative distance of the following vehicle to the traveling straddle-type vehicle. The stability degree of the relative distance becomes higher as the stability index value is increased. The determination section is configured to determine that the assistance operation is necessary in the case where the collision index value is an index value with the higher collision possibility than a determination criterion and the stability index value is an index value with the higher stability degree than a determination criterion.

In the processor, the rider-assistance system, the straddle-type vehicle, and the processing method according to the present invention, the surrounding environment information, which includes the information on the surrounding environment behind the straddle-type vehicle, is acquired. The necessity of the assistance operation for the rider executed by the rider-assistance system is determined by using: the collision index value that is an index value depending on the information on the surrounding environment at the rear and is the index value of the collision possibility of the following vehicle against the traveling straddle-type vehicle; and the stability index value that is the index value depending on the information on the surrounding environment at the rear and is the index value of the stability degree of the relative distance of the following vehicle to the traveling straddle-type vehicle. Thus, it is possible to execute the assistance operation for the rider regarding the collision by the following vehicle on the basis of the determination with high reliability. Therefore, the rider's safety is improved.

A description will hereinafter be made on a processor, a rider-assistance system, a straddle-type vehicle, and a processing method according to the present invention with reference to the drawings.

Note that each of a configuration, operation, and the like, which will be described below, is merely one example, and the processor, the rider-assistance system, the straddle-type vehicle, and the processing method according to the present invention are defined by the appended claims.

For example, a description will hereinafter be made on a case where the rider-assistance system according to the present invention is used for a two-wheeled motor vehicle. However, the rider-assistance system according to the present invention may be used for the straddle-type vehicle other than the two-wheeled motor vehicle. The straddle-type vehicle means a vehicle in general that a rider straddles. The straddle-type vehicles include motorcycles (the two-wheeled motor vehicle and a three-wheeled motor vehicle), an all-terrain vehicle, a pedal-driven vehicle, and the like. The motorcycles include: the two-wheeled motor vehicle or the three-wheeled motor vehicle that has an engine as a propelling source; the two-wheeled motor vehicle or the three-wheeled motor vehicle that has a motor as the propelling source; and the like, and include a motorcycle, a scooter, an electric scooter, and the like, for example. The pedal-driven vehicle means a vehicle in general that can travel forward on a road by a depressing force applied to pedals by the rider. The pedal-driven vehicles include a normal pedal-driven vehicle, an electrically-assisted pedal-driven vehicle, an electric pedal-driven vehicle, and the like.

The same or similar description will appropriately be simplified or will not be made below. In the drawings, the same or similar portions will be denoted by the same reference signs. In addition, a detailed structure will appropriately be illustrated in a simplified manner or will not be illustrated.

A description will hereinafter be made on a rider-assistance system according to an embodiment.

A description will be made on a configuration of the rider-assistance system according to the embodiment.

<FIG> is a view of a mounted state of the rider-assistance system according to the embodiment of the present invention on a straddle-type vehicle. <FIG> is a system configuration diagram of the rider-assistance system according to the embodiment of the present invention.

As illustrated in <FIG>, a rider-assistance system <NUM> is mounted on a straddle-type vehicle <NUM>. The rider-assistance system <NUM> at least includes: a surrounding environment detector <NUM> that detects surrounding environment behind the straddle-type vehicle <NUM>; a travel state detector <NUM> that detects a travel state of the straddle-type vehicle <NUM>; a processor (ECU) <NUM>; and an execution device P that executes assistance operation.

The rider-assistance system <NUM> plays a role of recognizing a collision possibility by a following vehicle against the traveling straddle-type vehicle <NUM> by using the surrounding environment detector <NUM> and assisting a rider by using the execution device P. The processor <NUM> acquires output of the surrounding environment detector <NUM> and output of the travel state detector <NUM>, and outputs a control command to the execution device P. The processor <NUM> also receives output of various detectors (not illustrated) for detecting other information (for example, information on a brake operation state by the rider, information on an accelerator operation state by the rider, and the like). Each section of the rider-assistance system <NUM> may exclusively be used for the rider-assistance system <NUM>, or may be shared with another system.

The surrounding environment detector <NUM> is a radar, a Lidar sensor, an ultrasonic sensor, a camera, or the like, for example, and continuously detects a distance and a direction of an object within a detection range from the straddle-type vehicle <NUM> during travel and a stop of the straddle-type vehicle <NUM>. The surrounding environment detector <NUM> is preferably fixed to a portion behind a seat in the straddle-type vehicle <NUM>.

The travel state detector <NUM> is a wheel speed sensor, an inertia sensor (IMU), and the like, for example, and detects a speed, acceleration, a roll angle, and the like that are generated on the straddle-type vehicle <NUM>, for example.

The processor <NUM> includes an acquisition section <NUM>, a determination section <NUM>, and a control section <NUM>. The sections of the processor <NUM> may collectively be provided in a single casing or may separately be provided in multiple casings. The processor <NUM> may partially or entirely be constructed of a microcomputer, a microprocessor unit, or the like, may be constructed of a member in which firmware or the like can be updated, or may be a program module or the like that is executed by a command from a CPU or the like, for example.

The acquisition section <NUM> acquires surrounding environment information, which includes information on the surrounding environment behind the straddle-type vehicle <NUM>, on the basis of the output of the surrounding environment detector <NUM>. The acquisition section <NUM> also acquires travel state information, which is information on the travel state of the straddle-type vehicle <NUM>, on the basis of the output of the travel state detector <NUM>.

The determination section <NUM> specifies an advancing direction of the straddle-type vehicle <NUM> from the travel state information acquired by the acquisition section <NUM>, and specifies the following vehicle (a vehicle that travels behind the straddle-type vehicle <NUM> while following the straddle-type vehicle <NUM>), the collision possibility of which should be determined, from the surrounding environment information acquired by the acquisition section <NUM>. The determination section <NUM> may specify a travel lane of the straddle-type vehicle <NUM> from the surrounding environment information acquired by the acquisition section <NUM>, and may specify a vehicle that travels on the same travel lane as the travel lane as the following vehicle, the collision possibility of which should be determined (the vehicle that travels behind the straddle-type vehicle <NUM> while following the straddle-type vehicle <NUM>). Then, the determination section <NUM> derives a collision index value I, which is the collision possibility of the following vehicle against the straddle-type vehicle <NUM>, for each of the specified following vehicles. That is, the collision index value I is an index value that depends on the information on the surrounding environment at the rear, and is defined as an index value of the collision possibility of the following vehicle against the straddle-type vehicle <NUM>. The determination section <NUM> determines for each of the specified following vehicles whether the derived collision index value I exceeds a reference value, and thereby determines whether the following vehicle with the high collision possibility exists behind the straddle-type vehicle <NUM>. The reference value may vary according to a setting state by the rider.

The collision index value I may be a reciprocal of a relative distance Dr of the following vehicle to the straddle-type vehicle <NUM>, may be a relative speed Vr of the following vehicle to the straddle-type vehicle <NUM>, may be relative acceleration Ar of the following vehicle to the straddle-type vehicle <NUM>, or a combination of those. For example, the collision index value I is a value that is defined by Formula <NUM> or Formula <NUM> below. Here, it means that the collision possibility becomes higher as the collision index value I is increased. <MAT><MAT>.

The determination section <NUM> also derives a stability index value J for each of the following vehicles specified as the following vehicles, the collision possibility of which should be determined, and the stability index value J represents a stability degree of the relative distance Dr of each of the following vehicles to the straddle-type vehicle <NUM>. That is, the stability index value J is an index value that depends on the information on the surrounding environment at the rear, and is defined as an index value of the stability degree of the relative distance Dr of the following vehicle to the straddle-type vehicle <NUM>. The determination section <NUM> determines for each of the specified following vehicles whether the derived stability index value J exceeds a reference value, and thereby determines whether the following vehicle that travels at a substantially equal speed to that of the straddle-type vehicle <NUM> exists behind the straddle-type vehicle <NUM>. The reference value may vary according to a setting state by the rider.

For example, the stability index value J is a value that varies according to a time in which an absolute value of the relative speed Vr of the following vehicle to the straddle-type vehicle <NUM> is maintained to be equal to or smaller than a reference amount, that is, a time in which a fluctuation amount of the relative distance Dr is maintained to be equal to or smaller than the reference amount. In addition, for example, the stability index value J is a value that varies according to an average value of the absolute value of the relative speed Vr in a reference time, that is, the fluctuation amount of the relative distance Dr in the reference time. Here, it means that the stability degree of the relative distance Dr becomes higher as the stability index value J is increased.

Then, if it is determined that the following vehicle with the high collision possibility exists behind the straddle-type vehicle <NUM> and that the following vehicle travels behind the straddle-type vehicle <NUM> at the substantially equal speed to that of the straddle-type vehicle <NUM>, the determination section <NUM> determines that the assistance operation is necessary. If not, the determination section <NUM> determines that the assistance operation is not necessary. In the case where the determination section <NUM> determines that the assistance operation is necessary, the control section <NUM> makes the execution device P execute the assistance operation.

The execution device P includes an alarm <NUM>. The alarm <NUM> executes notification operation to the rider as the assistance operation. The alarm <NUM> may notify the rider by sound (that is, a sensation through an auditory organ as a sensory organ), may notify the rider by a display (that is, a sensation through a visual organ as the sensory organ), may notify the rider by vibrations (that is, a sensation through a tactile organ as the sensory organ), or may notify the rider by a combination of those. More specifically, the alarm <NUM> is a speaker, a display, a lamp, a vibrator, or the like, may be provided to the straddle-type vehicle <NUM>, or may be provided to an accessory such as a helmet that is associated with the straddle-type vehicle <NUM>. In addition the alarm <NUM> may be constructed of a single output device or may be constructed of multiple output devices of the same type or different types. The multiple output devices may be provided integrally or may be provided separately.

The execution device P includes a warning device <NUM>. The warning device <NUM> executes warning operation to the following vehicle as the assistance operation. The warning device <NUM> may warn the following vehicle by the display (that is, the sensation through the visual organ as the sensory organ), may warn the following vehicle by the sound (that is, the sensation through the auditory organ as the sensory organ), or may warn the following vehicle by a combination of those. More specifically, the warning device <NUM> is the lamp, the display, the speaker, or the like, may be provided to the straddle-type vehicle <NUM>, or may be provided to the accessory such as the helmet that is associated with the straddle-type vehicle <NUM>. In particular, the warning device <NUM> is preferably a brake lamp of the straddle-type vehicle <NUM>. In addition, the warning device <NUM> may be constructed of the single output device or may be constructed of the multiple output devices of the same type or the different types. The multiple output devices may be provided integrally or may be provided separately.

The execution device P includes a speed controller <NUM> that is provided to the straddle-type vehicle <NUM>. The speed controller <NUM> executes speed correction operation as the assistance operation. The speed correction operation is operation to correct acceleration/deceleration or the speed that is generated on the straddle-type vehicle <NUM> by adaptive cruise control of the straddle-type vehicle <NUM>. The speed controller <NUM> may control operation of a mechanism that generates a propelling force on the straddle-type vehicle <NUM>, or may control operation of a mechanism that generates a braking force on the straddle-type vehicle <NUM>. For example, under a situation where the straddle-type vehicle <NUM> is automatically decelerated by the adaptive cruise control, in the case where the determination section <NUM> determines that the assistance operation is necessary, the execution device P executes the speed correction operation to reduce target deceleration in the automatic deceleration for correction. The execution device P may execute the speed correction operation to increase a target speed in the automatic deceleration for the correction. In addition, for example, under a situation where the straddle-type vehicle <NUM> is automatically accelerated by the adaptive cruise control, in the case where the determination section <NUM> determines that the assistance operation is necessary, the execution device P executes the speed correction operation to increase target acceleration in the automatic acceleration for the correction. The execution device P may execute the speed correction operation to increase the target speed in the automatic acceleration for the correction.

Note that the adaptive cruise control is defined as control to make the straddle-type vehicle <NUM> travel according to a distance from the straddle-type vehicle <NUM> to a preceding vehicle, motion of the straddle-type vehicle <NUM>, and the rider's instruction. Since details of the adaptive cruise control is already well-known for other vehicles such as an automobile, the description thereon will not be made. The straddle-type vehicle <NUM> is provided with a surrounding environment detector (not illustrated) that acquires forward surrounding environment information.

The execution device P may include a device other than the alarm <NUM>, the warning device <NUM>, and the speed controller <NUM>. In addition, any of the alarm <NUM>, the warning device <NUM>, and the speed controller <NUM> may not be provided. Furthermore, the rider-assistance system <NUM> may actuate the alarm <NUM>, the warning device <NUM>, and the speed controller <NUM> simultaneously, or may actuate the alarm <NUM>, the warning device <NUM>, and the speed controller <NUM> at different timing.

A description will be made on operation of the rider-assistance system according to the embodiment.

<FIG> is a chart of an operation flow of the processor in the rider-assistance system according to the embodiment of the present invention.

The processor <NUM> repeatedly executes the operation flow illustrated in <FIG> during the travel of the straddle-type vehicle <NUM>.

In step S101, the acquisition section <NUM> acquires the surrounding environment information that corresponds to the output of the surrounding environment detector <NUM>. The acquisition section <NUM> also acquires the travel state information that corresponds to the output of the travel state detector <NUM>.

In step S102, on the basis of the information acquired in step S101, the determination section <NUM> determines whether the following vehicle with the high collision possibility exists behind the straddle-type vehicle <NUM> and the following vehicle travels behind the straddle-type vehicle <NUM> at the substantially equal speed to that of the straddle-type vehicle <NUM>. If Yes, the processing proceeds to step S103. If No, the processing returns to step S101.

In step S103, the control section <NUM> makes the execution device P execute the assistance operation.

A description will be made on effects of the rider-assistance system.

The processor <NUM> includes: the acquisition section <NUM> that acquires the surrounding environment information about the straddle-type vehicle <NUM>; the determination section <NUM> that determines the necessity of the assistance operation executed by the rider-assistance system <NUM> to assist with the rider's operation; and the control section <NUM> that makes the execution device P execute the assistance operation in the case where the determination section <NUM> determines that the assistance operation is necessary. The surrounding environment information includes the information on the surrounding environment behind the straddle-type vehicle <NUM>. The determination section <NUM> determines the necessity of the assistance operation by using: the collision index value I, which is the index value depending on the information on the surrounding environment at the rear and is the index value of the collision possibility of the following vehicle against the traveling straddle-type vehicle <NUM>; and the stability index value J, which is the index value depending on the information on the surrounding environment at the rear and is the index value of the stability degree of the relative distance Dr of the following vehicle to the traveling straddle-type vehicle <NUM>. Thus, it is possible to execute the assistance operation for the rider regarding the collision by the following vehicle on the basis of the determination with high reliability. Therefore, the rider's safety is improved.

The determination section <NUM> determines that the assistance operation is necessary in the case where the collision index value I is the index value with the higher collision possibility than a determination criterion and the stability index value J is the index value with the higher stability degree than a determination criterion. With such a configuration, the assistance operation for the rider can be executed in a state where the following vehicle, the collision possibility of which is not extremely high, travels at the substantially equal speed to that of the straddle-type vehicle <NUM>. Therefore, the rider's safety is improved.

Preferably, the collision index value I is a value that varies according to at least one of the relative distance Dr, the relative speed Vr, and the relative acceleration Ar of the following vehicle to the traveling straddle-type vehicle <NUM>. With such a configuration, it is possible to execute the assistance operation for the rider regarding the collision by the following vehicle on the basis of the determination with higher reliability. Therefore, the rider's safety is improved.

Preferably, the stability index value J is the value that varies according to the time in which the fluctuation amount of the relative distance Dr is maintained to be equal to or smaller than the reference amount. With such a configuration, it is possible to execute the assistance operation for the rider regarding the collision by the following vehicle on the basis of the determination with higher reliability. Therefore, the rider's safety is improved.

Preferably, the stability index value J is the value that varies according to the fluctuation amount of the relative distance Dr in the reference time. With such a configuration, it is possible to execute the assistance operation for the rider regarding the collision by the following vehicle on the basis of the determination with higher reliability. Therefore, the rider's safety is improved.

Preferably, the determination section <NUM> changes at least one of the determination criterion of the collision index value I and the determination criterion of the stability index value J according to the setting state by the rider. With such a configuration, the rider's comfort and the rider's safety can be realized simultaneously.

Preferably, the execution device P includes the alarm <NUM>, and the assistance operation includes the notification operation to the rider executed by the alarm <NUM>. With such a configuration, the rider's safety against the collision by the following vehicle is improved.

Preferably, the execution device P includes the warning device <NUM>, and the assistance operation includes the warning operation to the following vehicle that is executed by the warning device <NUM>. With such a configuration, the rider's safety against the collision by the following vehicle is improved.

Preferably, the execution device P includes the speed controller <NUM> that is provided to the straddle-type vehicle <NUM>. The assistance operation includes the speed correction operation, which is executed by the speed controller <NUM> to correct the acceleration/deceleration or the speed generated on the straddle-type vehicle <NUM> by adaptive cruise control of the straddle-type vehicle <NUM>. With such a configuration, the rider's safety against the collision by the following vehicle is improved.

The description has been made so far on the case where the surrounding environment detector <NUM> is provided to the straddle-type vehicle <NUM>. However, according to an example not covered by the claims, the surrounding environment detector <NUM> may be provided to a different vehicle from the straddle-type vehicle <NUM>. That is, the acquisition section <NUM> may acquire the surrounding environment information by inter-vehicular communication. In particular, the surrounding environment detector <NUM> is preferably provided to the following vehicle with the collision possibility.

Claim 1:
A processor (<NUM>) for a rider-assistance system (<NUM>) of a straddle-type vehicle (<NUM>), the processor (<NUM>) comprising:
an acquisition section (<NUM>) that acquires surrounding environment information about the straddle-type vehicle (<NUM>);
a determination section (<NUM>) that determines necessity of assistance operation executed by the rider-assistance system (<NUM>) to assist with a rider's operation on the basis of the surrounding environment information acquired by the acquisition section (<NUM>); and
a control section (<NUM>) that outputs a control command to an execution device (P) to execute the assistance operation in the case where the determination section (<NUM>) determines that the assistance operation is necessary, wherein
the surrounding environment information includes information on surrounding environment behind the straddle-type vehicle (<NUM>),
the surrounding environment information is information corresponding to output of a surrounding environment detector (<NUM>) provided to the straddle-type vehicle (<NUM>),
the determination section (<NUM>) determines the necessity of the assistance operation by using:
a collision index value (I) that is an index value depending on the information on the surrounding environment at the rear and is an index value of a collision possibility of a following vehicle against the traveling straddle-type vehicle (<NUM>), wherein the collision possibility becomes higher as the collision index value (I) is increased; and
a stability index value (J) that is an index value depending on the information on the surrounding environment at the rear and is an index value of a stability degree of a relative distance (Dr) of the following vehicle to the traveling straddle-type vehicle (<NUM>),characterized in that
the stability degree of the relative distance (Dr) becomes higher as the stability index value (J) is increased ; and
the determination section (<NUM>) is configured to determine that the assistance operation is necessary in the case where the collision index value (I) is an index value with the higher collision possibility than a determination criterion and the stability index value (J) is an index value with the higher stability degree than a determination criterion.