JPH0740756A - Awakening level deciding device and electronic control type steering device - Google Patents

Abstract

PURPOSE:To provide an awakening level deciding device which can decide the awakening level of a driver securely by grasping the condition of his health, and an electronic control type power steering device which can obtain an optimum steering performance according to the running condition of the driver by applying the awakening level deciding device. CONSTITUTION:In a steering awakening level deciding device, a car speed sensor 41 to detect the running speed V of a vehicle, a steering angle sensor 52 to detect the steering angle ha of the vehicle, and a steering force sensor 53 to detect the steering force hf of the vehicle are provided, the average value of the steering workload is computed depending on the steering angle ha and the steering force hf, and the resaltant steering awakening level detecting value Wd and a standard value Ws are compared to decide the reduction of the awakening level of a driver. The steering awakening level detecting device is applied to an electronic control type power steering device, and an object assist amount is set by a fuzzy operation member 56 by making the car speed V, the steering angle ha, and the steering awakening level coefficient Kw as the input conditions (membership functions).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wakefulness determining device for determining the wakefulness of a human such as a driver of a vehicle, a ship, a pilot of an airplane, and a steering mechanism of a vehicle equipped with the wakefulness determining device. The present invention relates to an electronically controlled power steering device that electronically controls a steering assist amount, for example, by setting a target assist amount by a fuzzy rule.

[0002]

2. Description of the Related Art In recent years, due to the remarkable development of road networks, the mobility of automobiles has been greatly improved, and the radius of action has been expanded. At the same time, the stability of life and the increase in leisure have strengthened the family's leisure orientation. , The opportunity to drive a car is increasing in everyday life. When driving a vehicle, the driver is always required to have stable physical and mental health, but in general, the driver tends to neglect the physical condition and hold the steering wheel in most cases while being aware of the poor physical condition. Although it is desirable to drive a car within an appropriate range that suits one's physical condition, there are cases in which the user is overwhelmed without being aware of his own physical condition. When the vehicle is continuously driven for a long time without any break, fatigue is accumulated in the driver, the health condition is deteriorated, and the concentration is decreased, which may cause an accident.

Therefore, conventionally, a drowsy driving warning device is provided in a vehicle to give a signal to a driver for a response at a certain time interval, and a warning is given by determining a decrease in arousal level depending on the appropriateness of the driver's response time. There is something. However, with this conventional device, the driver may be required to respond when the driver has to concentrate on the nerves, such as when driving in the city or on a curve, and when the alertness is not lowered, the driver is annoyed. won.

Therefore, it is considered to prevent an accident by monitoring the driving condition according to one's own physical condition and notifying the driver of this when the driving limit is exceeded, for example, Japanese Patent Laid-Open No. 1-131648. Is disclosed in. It is generally known that the heart rate of the human heart increases or decreases according to driving intensity, mental tension, or fear. Therefore, in the wakefulness determination device disclosed in this publication, the sensor detects the heart rate of the driver who is driving the vehicle, and the cycle of the heart rate is sequentially calculated.
The driver's arousal level is determined by converting and determining whether or not the value is within the allowable range. Please refer to the official gazette for details.

On the other hand, in recent years, a power steering device has become widespread in order to assist a force for operating a steering wheel (hereinafter referred to as a steering wheel) (hereinafter referred to as a steering wheel operating force or a steering force). As this power steering device, a hydraulic power steering device that assists steering by hydraulic pressure using a hydraulic cylinder mechanism is generally used, but in addition to this, an electric power steering device that assists steering by an electric motor has also been developed. ing.

By using such a power steering device, even a vehicle requiring a large steering wheel operating force such as a large vehicle or a vehicle having wide tires mounted on the steered wheels can be operated with a small steering wheel operating force. The steering wheel can be steered, and the so-called weight of the steering wheel is eliminated. By the way, in general, at low speeds such as when entering a garage, it is desirable to make the handle lighter so that it can be operated lightly. On the other hand, when driving at high speed, if the steering wheel is too light, traveling will be unstable, so we would like to make it heavier so that it can be operated stably. Therefore, a vehicle speed-sensitive power steering device has been developed in which the steering assist amount is increased at low speeds according to the vehicle speed, and the steering assist amount is decreased at high speeds at medium and high speeds.

As such a vehicle speed-sensitive power steering apparatus, a vehicle speed sensor is provided in the vehicle, and a valve or the like for adjusting the hydraulic pressure supplied to the power steering is provided in a part of the hydraulic system of the hydraulic power steering apparatus. There is one in which the steering assist amount is adjusted while electronically controlling the operation of valves and the like based on the vehicle speed detected by a vehicle speed sensor (this is called an electronically controlled power steering device).

FIG. 15 is a schematic configuration of a hydraulic control unit for power steering showing an example of a conventional electronically controlled power steering device, FIG. 16 is a sectional view taken along line XVI-XIVI of FIG.
15 shows a cross section taken along line XVII-XVII of FIG.

As shown in FIGS. 15 to 17, reference numeral 11 denotes an input shaft which receives a steering force from a steering wheel (handle) (not shown), which is rotatably supported in the casing 12 by bearings. A pinion gear 13 is rotatably attached to the lower end of the input shaft 11 via a bush or the like (not shown).
A torsion bar 14 is provided inside the hollow portion of the input shaft 11.
While its upper end is coupled to the input shaft 11 by a pin so that it can rotate integrally, its lower end is free from being restrained with respect to the input shaft 11.

The pinion gear 13 at the lower end of the input shaft 11 is serrated with the lower end of the torsion bar 14 so that the steering force input to the input shaft 11 is transmitted to the pinion gear 13 via the torsion bar 14. There is. The pinion gear 13 meshes with the rack 15, and the steering force by the input shaft 11 is transmitted to the rack 15 via the pinion gear 13, and the rack 15 is driven in the axial direction (the direction orthogonal to the paper surface in FIG. 15) to rotate the wheels (not shown). It is possible to steer.

In the casing 12, a rotary valve 16 is interposed between the input shaft 11 side and the pinion gear 13 side.
Is opened and closed according to the phase difference in the circumferential direction between the input shaft 11 and the pinion gear 13. The rotary valve 16 has an operating oil supply pipe 18 and an oil reservoir 1 of an oil pump 17 provided outside.
The hydraulic oil discharge pipe 20 of 9 is connected. On the other hand, reference numeral 21 is a hydraulic cylinder for power steering, and this hydraulic cylinder 21 is constituted by a piston 23 supported in a hollow cylinder 22 installed in a predetermined member on the vehicle body side so as to be axially movable. The piston shaft 24 is fixed to the middle of the rack 15 described above. Then, the piston 23 partitions the inside of the cylinder 22 into right and left, and the oil chamber 2
5 and 26 are formed.

Therefore, when the steering force is input to the input shaft 11, the input shaft 11 is rigid and hardly twists, but the torsion bar 14 transmits the steering force to the pinion gear 13 while twisting. . Then, the pinion gear 13 is connected to the input shaft 11
As a result, a phase difference is generated on the steering side, and the rotary valve 16 is driven according to this phase difference. The oil pump 17 is opened and closed according to the opening and closing of the rotary valve 16.
The hydraulic oil is supplied from the hydraulic oil supply pipe 18 to the left and right oil chambers 25 and 26 of the hydraulic cylinder 22 to give a steering assist force to the rack 15 and a required steering assist force in the steering direction. It is happening.

Further, inside the casing 12, a reaction force plunger 27 is provided on the outer periphery of the lower portion of the input shaft 11 to increase the steering force (steering response) by applying a steering reaction force during steering. A plurality of the reaction force plungers 27 are provided so as to surround the outer circumference of the input shaft 11, receive the hydraulic pressure supplied through the control of the hydraulic control valve 28, and restrain the input shaft 11 according to the hydraulic pressure to steer the input shaft 11. It is designed to give a reaction force.

That is, four reaction force plungers 27 are provided in the casing 12 at equal intervals so as to surround the outer circumference of the input shaft 11. A chamber 29 is formed on the outer end side thereof and a return orifice 30 is provided. Is provided. On the other hand, the hydraulic control valve 18 is provided in the casing 12 adjacent to the side of the input shaft 11 in parallel therewith. In this hydraulic control valve 28, a spool 31 is provided inside the casing 12.
Is movably provided up and down, and the spool 31 is biased and supported downward by a spring 32 provided at the upper portion. Further, a solenoid 33 is provided on the lower outer peripheral piece of the spool 31, and an axial force is applied to the spool 31 by exciting the solenoid 33.

The spool 31 has an oil reservoir 19
Oil passages 34 and 35 communicating with the hydraulic oil discharge pipe 20 and an annular oil passage 36 communicating with the hydraulic oil supply pipe 18 of the oil pump 17 are formed, and the chamber 2 of the reaction force plunger 27 is formed.
An annular oil passage 38, which communicates with the hydraulic oil supply / discharge pipe 37, and an oil passage 39, which communicates the annular oil passages 36, 38 with each other, are formed in the shaft 9. Therefore, normally, when the solenoid 33 is demagnetized, the spool 31 is in the lowered position and the hydraulic oil supply pipe 18
And the annular oil passage 36 communicate with each other. Therefore, the hydraulic oil supplied from the oil pump 17 to the hydraulic control valve 28 via the hydraulic oil supply pipe 18 is transferred from the annular oil passage 36 to the oil passage 3
9. The reaction force is supplied to the chamber 29 of the plunger 27 through the annular oil passage 38. On the other hand, in the excited state of the solenoid 33, the spool 31 is in the raised position, and the hydraulic oil supply pipe 18 and the annular oil passage 36 are not in communication with each other. Therefore, from the oil pump 17 to the hydraulic oil supply pipe 18
The hydraulic fluid supplied to the hydraulic control valve 28 via the is not supplied to the chamber 29 of the reaction force plunger 27.

By adjusting the current applied to the solenoid 33 in this way, the steering assist characteristic can be controlled. Further, a vehicle speed sensor 41, an engine speed sensor 42, etc. are connected to a control unit (CU) 40 that controls the solenoid 33, and the control unit 40 supplies the amount of current to the solenoid 33 based on output signals from these. Can be set to control the solenoid 33.

Thus, for example, the maximum current is applied to the solenoid 33 when the vehicle is stationary or steering at low speed. As a result, the spool 31 moves up to the maximum, the annular oil passage 36 is no longer communicated with the hydraulic oil supply pipe 18 of the oil pump 17, and the oil is not supplied to the chamber 29 of the reaction force plunger 27. Therefore, the input shaft 11 is not restrained by the reaction force plunger 27, and the steering wheel can be steered lightly.

Then, for example, when the vehicle is running at a high speed, the current supplied to the solenoid 33 is decreased as the vehicle speed increases. Then, when the steering wheel is in the neutral position, the axial force of the spool 31 is reduced due to the current phenomenon, and the spool 31 is lowered accordingly, so that the annular oil passage 36 is closed.
7 and the hydraulic oil supply pipe 18 of No. 7, and the oil is supplied to the chamber 29 of the reaction force plunger 27. Therefore, since the input shaft 11 is restrained by the reaction force plunger 27, the handle is held neutral. When the steering wheel is slightly steered in this neutral state, the output of the oil pump 17 tries to increase, but this discharge pressure is hardly controlled by the hydraulic control valve 28 and acts on the chamber 29 of the reaction force plunger 27. . Therefore, in the vicinity of the neutral state of the steering wheel, the steering force is increased, and the response of the neutral steering wheel can be sufficiently obtained, and the sense of steering stability in the neutral state is increased.

Further, when steering is performed during medium-high speed traveling, the output of the oil pump 17 increases in response to steering of the steering wheel (in response to an increase in steering force) within the normal steering range, and steering assist is increased. Acts like. On the other hand, the discharge pressure of the oil pump 17 acts on the chamber 29 of the reaction force plunger 27 while being controlled by the hydraulic pressure control valve 28.
Therefore, the input shaft 11 is restrained by the reaction force plunger 27, and the steering response (steering force) can be increased.

As a result, the steering force at the time of steering at medium and high speeds is increased by the amount of the reaction force plunger 27 acting as compared with that at the time of stationary steering and steering at low speeds. That is, the steering response is increased and a stable steering feeling is obtained. In particular, by decreasing the current supplied to the solenoid 33 according to the increase of the vehicle speed, the steering assist decreases and the steering force (steering response) increases as the vehicle speed increases, and a more stable steering feeling can be obtained. it can.

Further, a vehicle speed sensor 41 and an engine speed sensor 42 are connected to a control unit 40 for controlling the solenoid 33, and an abnormality such as a detection system is detected from the vehicle speed signal and the engine speed signal, and the solenoid 33 is detected. Fail-safe control can be performed by turning off.

[0022]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the conventional wakefulness determination device described in Japanese Patent No. 31648, a heartbeat sensor (photocoupler) detects the heartbeat of a driver who is driving, and the wakefulness of the driver is detected based on the detected heartbeat data. Is being determined. The heart rate sensor is mounted on the steering wheel, and when the thumb of the driver's right hand touches the surface of the insulating substrate so as to cover the light emitting surface of the light emitting diode and the light receiving surface of the phototransistor, the light emitted from the light emitting diode is emitted. Is reflected by blood passing through a blood vessel in the thumb and is incident on the phototransistor, and a light reception signal is generated at a level corresponding to the incident amount, so that the pulse wave of the driver is detected.

When the vehicle is driven without rest for a long time, the driver accumulates fatigue, which reduces concentration and awakening, causing drowsiness and finally falling asleep. In the conventional wakefulness determination device, when detecting the heart rate of the driver, the driver must hold a predetermined position of the steering wheel and place the thumb of the right hand on the heart rate sensor (photocoupler). However, when the driver falls asleep, the gripping force of the hand is also reduced and the driver also releases the steering wheel, and the driver cannot hold the steering wheel at a predetermined position. Therefore, the heart rate sensor may not be able to detect the driver's heart rate, and may not be able to determine the driver's arousal level.

On the other hand, in the power steering device,
Actually, the driving state of the vehicle, that is, whether the vehicle is traveling straight or turning, whether accelerating or braking, and the steering force characteristics required by the driving state of the driver It is different. However, in the above-mentioned conventional electronically controlled power steering device,
Since the steering assist amount is simply controlled according to the vehicle speed, the driver cannot always obtain the optimum steering feeling.

For example, if the driver continuously drives the vehicle for a long time without any break, fatigue accumulates and the steering feeling of the steering wheel becomes dull. That is, in the conventional power steering apparatus, the steering assist amount is controlled in accordance with the vehicle speed, and the steering force is light at low speed traveling and has a certain weight at high speed traveling. Therefore, when the driver's health condition is good, the vehicle can be grasped by an appropriate change in the steering force by performing such control of the steering assist amount. However, as described above, when the driver continuously drives the vehicle without rest, fatigue accumulates, and the steering wheel feels heavier than when the vehicle is in good health. Therefore, when the driver is tired in this way, the optimum steering feeling is usually a burden.

As the electronically controlled power steering device, in addition to the above-mentioned one, there is a power steering device which changes the assist amount according to a fuzzy rule from a steering direction signal of a steering wheel and a vehicle height value signal of a vehicle. No. 171384. Also,
Japanese Patent Laid-Open No. 2-171385 discloses a power steering device that changes the assist amount according to a fuzzy rule based on a steering direction signal of a steering wheel and a temperature signal inside a vehicle.

However, even in these power steering devices, as described above, the steering assist amount of the steering wheel is controlled so that the running state of the vehicle can be appropriately grasped according to the driving state of the driver, that is, the changed state. Therefore, there is a problem that the optimum steering feeling cannot always be obtained.

The present invention solves such a problem and provides a wakefulness determination device capable of accurately recognizing the health condition of the driver and determining the wakefulness of the driver. It is an object of the present invention to provide an electronically controlled power steering device that can obtain an optimum steering characteristic according to a running state of a driver by applying a wakefulness determination device.

[0029]

SUMMARY OF THE INVENTION To achieve the above-mentioned object, a wakefulness determining device of the present invention comprises a steering angle detecting means for detecting a steering angle of a steering mechanism of a traveling vehicle, and a steering angle detecting means of the traveling vehicle. Steering force detecting means for detecting the steering force of the steering mechanism, and steering for calculating the steering awakening degree by calculating the average value of the steering work amount for each predetermined time based on the detection results of the steering angle detecting means and the steering force detecting means. Awakening degree calculation means,
The steering awakening degree determining means compares the steering awakening degree obtained by the steering awakening degree calculating means with a preset reference value to determine a decrease in the awakening degree.

On the other hand, the electronically controlled power steering device of the present invention for achieving the above object detects the traveling speed of the vehicle in the electronically controlled power steering device which electronically controls the steering assist amount in the steering mechanism of the vehicle. The vehicle speed detection means, the steering angle detection means for detecting the steering angle of the steering mechanism, the steering force detection means for detecting the steering force of the steering mechanism, and the detection results of the steering angle detection means and the steering force detection means. Based on the average value of the steering work amount for each predetermined time calculated on the basis of the steering arousal degree is compared with a preset reference value, a fatigue degree coefficient calculating means for calculating a driver's fatigue degree coefficient, and the vehicle And a target assist amount setting means for setting a target assist amount with the running speed and the driver's fatigue coefficient as input conditions. It is intended.

Further, the electronically controlled power steering device of the present invention is an electronically controlled power steering device for electronically controlling the steering assist amount in a steering mechanism of a vehicle, and a vehicle speed detecting means for detecting a traveling speed of the vehicle, and the steering wheel. Steering angle detecting means for detecting the steering angle of the mechanism, steering force detecting means for detecting the steering force of the steering mechanism, and for every predetermined time calculated based on the detection results of the steering angle detecting means and the steering force detecting means. Fatigue coefficient calculating means for calculating the driver's fatigue coefficient by comparing the steering arousal degree obtained from the average value of the steering work with a preset reference value, and the running speed of the vehicle and the driver's fatigue degree. And a target assist amount setting means for setting a target assist amount based on a fuzzy rule using a coefficient as an input condition. Than it is.

Further, in the electronically controlled power steering device according to the present invention, in the electronically controlled power steering device according to claim 3, the target assist amount setting means is a membership function for evaluating the traveling speed of the vehicle and the driver. Using a membership function for evaluating a fatigue factor, the target assist amount is increased as the traveling speed of the vehicle is decreased, and the target assist amount is increased as the driver's fatigue factor is decreased. It is characterized in that the target assist amount is set based on a fuzzy rule.

[0033]

The steering angle detecting means detects the steering angle of the steering mechanism of the running vehicle, the steering force detecting means detects the steering force of the steering mechanism, and the steering alertness calculating means detects the steering angle detecting means and the steering force. Based on the steering angle and the steering force of the steering mechanism detected by the detection means, the steering wakefulness is calculated by calculating the average value of the steering work amount for each predetermined time, and the steering wakefulness determination means is calculated by the steering wakefulness calculation means. The reduction of the driver's arousal level is determined by comparing the obtained steering arousal level with a preset reference value. Therefore, the awakening degree of the driver can be accurately determined based on the steering work amount of the steering wheel regardless of the steering wheel holding position of the driver.

The vehicle speed detecting means detects the traveling speed of the vehicle,
Further, the steering angle detecting means detects the steering angle of the steering mechanism, the steering force detecting means detects the steering force, and the fatigue coefficient calculating means performs steering at predetermined time intervals calculated based on the steering angle and the steering force. The driver's fatigue degree coefficient is calculated by comparing the steering arousal degree obtained from the average value of the work amount with a preset reference value, and the target assist amount setting means sets the running speed of the vehicle and the driver's fatigue degree coefficient. By setting the target assist amount with and as input conditions, optimum steering characteristics can be obtained according to the running state of the vehicle and the health condition of the driver.

Further, since the target assist amount setting means sets the target assist amount based on the fuzzy rule using the traveling speed of the vehicle and the driver's fatigue coefficient as input conditions, fine control can be performed with a small number of rules. Becomes

The target assist amount setting means uses a membership function for evaluating the traveling speed of the vehicle and a membership function for evaluating the driver's fatigue coefficient, and sets the target assist amount as the traveling speed of the vehicle decreases. The target assist amount is set by a fuzzy rule that increases and increases the target assist amount as the driver's fatigue coefficient decreases. Therefore, as the steering assist amount is increased in accordance with the decrease in the vehicle speed and the fatigue factor, the steering force characteristic becomes lighter as the vehicle speed becomes lower and the driver accumulates fatigue, and the steering operation feeling becomes easy. Becomes

[0037]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a schematic structure of a vehicle drowsiness warning device having a wakefulness determination device according to an embodiment of the present invention, FIG. 2 is a perspective view showing an outer appearance of a vehicle interior in this embodiment, and FIG. FIG. 4 and FIG. 5 are flowcharts showing the flow of the process of determining the driver's steering awakening degree, and FIGS.

In the awakening level determination device of this embodiment, the device shown in FIG.
As shown in FIG. 3, a vehicle speed sensor 41 that detects the traveling speed of the vehicle (hereinafter, referred to as vehicle speed V) is connected to the steering alertness calculating means 71. Further, a steering angle sensor 52 for detecting a deviation from a neutral position of the steering shaft in the steering mechanism (hereinafter referred to as steering angle ha), and a force acting on the steering shaft in the steering mechanism (hereinafter, steering force). A steering force sensor 53 that detects a force hf) is also connected to the steering alertness calculating means 71.

The steering awakening degree calculation means 71 has a vehicle speed V detected by the vehicle speed sensor 41 and a steering angle sensor 52.
The steering awakening degree is calculated by calculating the average value of the steering work amount based on the steering angle ha detected by the steering force sensor 53 and the steering force hf detected by the steering force sensor 53. Reference numeral 71 has a reference value calculation means 72 and a detection value calculation means 73. The reference value calculation means 72 calculates a reference value for determining whether or not the steering wakefulness of the driver is lowered, and it is assumed that the wakefulness is high within a predetermined time when the driver starts driving the vehicle. A reference value is calculated based on the steering angle ha and the steering force hf of the steering wheel. This reference value has individual differences, and is performed every time the driver changes. The detection value calculation means 73 is for obtaining the detection value of the steering awakening degree of the driver who is driving the traveling vehicle, and constantly calculates the detection value based on the steering angle ha and the steering force hf of the steering wheel during traveling. To do.

The steering alertness calculating means 71 (reference value computing means 72, detection value computing means 73) is connected to the steering alertness determining means 74, and the steering alertness determining means 74 is connected to the alarm means 75. There is. The steering wakefulness determination means 74 compares the detected value of the steering wakefulness calculated by the detected value calculation means 73 with the reference value of the steering wakefulness calculated by the reference value calculation means 72 to reduce the wakefulness of the driver. It is a judgment. Further, the warning means 75 is the steering alertness determination means 74.
An alarm is generated based on the driver's awakening degree lowering state determined in. In this case, this alarm means 7
There may be various types of devices 5, and they may be generated by the deformation of the driver's seat, may be generated by displaying them transparently on the front window of the vehicle, or may be a drowsiness alarm sound.

In this embodiment, as shown in FIG.
The vehicle speed sensor 41 is incorporated in a speedometer 81 in an instrument panel 80 of the vehicle. Steering angle sensor 52
The steering force sensor 53 is attached to a steering shaft (not shown) of the steering wheel 82. Further, in the warning means 75, the deformation of the driver's seat is performed by operating a pair of left and right side supports 84 provided on the seat back 83, and the transparent display on the front window is for transparently displaying the drowsiness warning on the dashboard 85. The display 86 is embedded, and when the power is on, the drowsiness warning mark 87 is transmitted through the front window 88, and the drowsiness warning sound is generated by sounding a warning buzzer 89 incorporated in the instrument panel 80. Although not shown, these alarms can be immediately released by the driver operating the release device.

The flow of processing in the steering wakefulness determination in the wakefulness determination device of this embodiment will be described with reference to FIG. As shown in FIG. 3, in step J1, the vehicle speed V from the vehicle speed sensor 41, the steering angle ha from the steering angle sensor 52, and the steering force hf from the steering force sensor 53 are read, and the routine proceeds to step J2. In step J2,
The steering wakefulness A _w is calculated and the process proceeds to step J3.
Here, the awakening degree of the driver is determined. That is, it is determined whether or not the steering wakefulness A _w is smaller than a determination value, which is 0.2 in this embodiment, and otherwise it is determined that the driver's wakefulness is high. On the other hand, if the steering wakefulness A _w of the driver is smaller than 0.2 in step J3, it is determined that the wakefulness of the driver has decreased, and an alarm is issued in step J4.

In this case, the alarm is issued by activating the side support 84 of the seat back 83, transmitting the drowsiness alarm mark 87 to the front window 88, and sounding the alarm buzzer 89, as described above. Further, the judgment value of the steering alertness A _w may be set in three stages and the alarm may be generated stepwise.

The flow of processing in the steering wakefulness calculation in the above-described steering wakefulness determination processing will be described with reference to FIGS. 4 and 5. As shown in FIGS. 4 and 5, the processing of the steering wakefulness calculation is started by turning on the ignition, and in step L1, the vehicle speed V is 30 km / h or more and the steering angle ha is 10 deg or more. If so, the driver determines that the vehicle is traveling, and proceeds to step L2. Then, in step L2, the steering angular velocity is calculated based on the steering angle ha.
Calculate ha 'from the following formula. ha ′ = | ha _n −ha _n−1 | / t Note that this calculation is performed every 50 milliseconds. Then, in step L3, the steering work amount W is calculated from the following equation based on the steering angular velocity ha 'and the steering force hf. W = ha '× hf

In step L4, the steering work amount W obtained in step L3 is accumulated, and in step L5, the reference value timer T _ws starts counting up. Then, in step L6, it is determined whether or not the count value of the reference value timer T _ws has reached 30 minutes. That is, the reference value W _s of the steering wakefulness is calculated based on the change in the steering work amount W for 30 minutes after the driver starts driving the vehicle,
If T _ws = 30, the process _proceeds to step L7. Then, in step L7, the steering work amount W in 30 minutes
The reference value W _s of the steering wakefulness is obtained from the following equation by calculating the average value of W _s = W _30/30

On the other hand, in step L6, the reference value
Mat T_wsIf the count value of is not 30 minutes, go to step L9.
If you are driving a vehicle that has
Detected value W of steering alertness of iva_dAsk for. That is, step
In step L9, the steering work amount W obtained in step L3 is
Accumulated, and in step L10, the detected value timer T_wdThe cow
Start up. And in step L11
Detection value timer T_wdCount value of 5 minutes
Determine whether. That is, the detected value W of the steering alertness _dDora
Steering work every 5 minutes since Iba started driving the vehicle
It is calculated based on the change in the quantity W, and T_wd= 5
If there is, the process proceeds to step L12. And step
At L12, the average value of the steering work W in 5 minutes is played.
By calculating, the detected value W of the steering alertness is calculated from the following formula._dSeeking
It W_d= W_Five/ 5 Then, in step L13, the reference value timer T_wdThe coun
Value is 0, and the steering work amount W is 5 minutes in step L14.
Cumulative value W between_FiveIs set to 0.

Then, in step L15, the step
Reference value W obtained with L7_s(30 minutes of steering work W
Average value of₃₀/ 30) and the detection obtained in step L12
Value W _d(The average value W of the steering work amount W for 5 minutes_Five/ 5) with
Ratio (W_d/ W_s) Steering arousal A_wTo calculate.

In step L15, the steering awakening is performed.
Degree reference value W_sAnd detection value W_dFrom the ratio with_w
Is calculated, but the reference value W of the steering wakefulness_sThe driver is a car
It is calculated 30 minutes after starting both operations.
This is a value that was not required before that. Therefore,
Less than 30 minutes after the driver starts driving the vehicle (T _ws
Up to <30), the standard value W of the steering alertness_sGeneral number to
Is given, the reference value W of the steering alertness_sCalculation of (W_s=
W₃₀/ 30) and then rewrite
It However, 30 minutes after the driver starts driving the vehicle
The driver's alertness is high until
It is not necessary to judge the rudder awakening degree.

As described above, in the wakefulness determination device of the present embodiment, the steering angle ha and the steering force hf of the steering mechanism of the running vehicle are detected, and the steering work amount for a predetermined time is detected based on the detection results. By calculating the average value of W, the reference value W _s of the steering wakefulness and the detection value W _d are obtained, and the reference value W _s of the steering wakefulness is compared with the detection value W _d to determine the wakefulness of the driver. Since the decrease is determined and the alarm is issued if the awakening level is decreased, it is possible to prevent a decrease in concentration when the driver is tired and prevent an accident.

Then, in the alertness determination device of this embodiment,
The steering angle sensor 52 and the steering force sensor 53 are provided in the steering mechanism, and the steering angle ha detected by the steering angle sensor 52 and the steering force hf detected by the steering force sensor 53 are applied as factors for determining the awakening degree of the driver. However, by performing various calculations based on the steering angle ha and the steering force hf, the driver's steering alertness is determined,
The device can be provided with a simple structure and at a low price.

Now, a case where the awakening degree determination device described above is applied to an electronically controlled power steering device for electronically controlling the steering assist amount in a steering mechanism of a vehicle will be described. That is, in the following examples, replace the steering awareness A _w of the driver as the fatigue coefficient K _w, and controls the steering assist amount in the steering mechanism by the increase or decrease of the fatigue factor K _w.

FIG. 6 is a schematic configuration of a hydraulic control unit for power steering according to an embodiment of an electronically controlled power steering device of the present invention, FIG. 7 is a graph showing a membership function of vehicle speed used for fuzzy control, and FIG. A graph showing the membership function of vehicle speed x lateral acceleration used for fuzzy control,
FIG. 9 is a graph showing the membership function of the fatigue coefficient used for fuzzy control, FIG. 10 is a graph showing the calculation processing for obtaining the power steering assist amount from the fitness of each membership function by the center of gravity method, and FIGS. FIG. 13 is a flowchart showing a flow of processing of fatigue factor calculation, FIG. 13 is a flowchart showing fuzzy control, and FIG. 14 is a flowchart showing calculation of the assist amount by the center of gravity method from each membership function of vehicle speed and vehicle speed × lateral acceleration, and fatigue coefficient. A specific control example will be shown. It should be noted that the members having the same functions as those of the related art are designated by the same reference numerals, and the duplicate description will be omitted.

The electronically controlled power steering device of this embodiment controls the hydraulic power steering control unit by fuzzy reasoning. The mechanical part (hardware configuration) of the electronically controlled power steering device is as described above. The configuration is almost the same as that of the conventional example, and that point will be briefly described.

As shown in FIG. 6, the input shaft 1
The reference numeral 1 receives a steering force from a steering wheel (handle) (not shown), and is rotatably supported in the casing 12. A pinion gear 13 is relatively rotatably mounted on the lower end of the input shaft 11, and a torsion bar 14 is provided inside the hollow portion of the input shaft 11, and only the upper end of the torsion bar 14 is connected to the input shaft 11. The pinion gear 13 is serrated with the lower end of the torsion bar 14, and
The pinion gear 13 meshes with the rack 15,
The steering force generated by the input shaft 11 is transmitted to the pinion gear 13 via the torsion bar 14 and further transmitted to the rack 15, and the rack 15 is axially driven to steer the wheels. .

The rotary valve 16 in the casing 12 is adapted to open and close in accordance with the phase difference in the circumferential direction between the input shaft 11 and the pinion gear 13, and the operation of the hydraulic oil supply pipe 18 and the oil reservoir 19 of the oil pump 17 is performed. The oil discharge pipe 20 is connected. On the other hand, the power steering hydraulic cylinder 21 is configured such that a piston 23 is supported in a cylinder 22 so as to be movable in the axial direction, and a piston shaft 24 of the piston 23 is fixed in the middle of the rack 15. The piston 23 divides the inside of the cylinder 22 into right and left to form oil chambers 25 and 26.

Therefore, when the steering force is input to the input shaft 11, the torsion bar 14 twists and transmits the steering force to the pinion gear 13, and the pinion gear 13 causes a phase difference with respect to the input shaft 11 on the steering side. As a result, the rotary valve 16 is driven according to this phase difference. The hydraulic pump 17 supplies hydraulic oil to the oil chambers 25 and 26 of the hydraulic cylinder 22 in response to the opening and closing of the rotary valve 16 to give a steering assist force to the rack 15 and a required steering direction. Steering assist force is generated.

A reaction force plunger 27 is provided on the outer periphery of the lower portion of the input shaft 11 to increase the steering force (steering response) at the time of steering, and the input shaft 11 is controlled by the hydraulic control valve 28.
The steering reaction force is applied by restraining the vehicle. That is,
In this embodiment, four reaction force plungers 27 are provided in the casing 12 at equal intervals so as to surround the outer circumference of the input shaft 11, and a chamber 29 is formed on the outer end side thereof. On the other hand, the hydraulic control valve 28 is provided in the casing 12 adjacent to the side of the input shaft 11 and in parallel therewith. In this hydraulic control valve 18, the spool 3 is provided in the casing 12.
1 is movably provided up and down, and the spool 31 is biased and supported downward by a spring 32 provided at the upper portion. Further, a solenoid 33 is provided on the lower outer peripheral piece of the spool 31, and an axial force is applied to the spool 31 by exciting the solenoid 33.

The spool 31 has an oil reservoir 19
Oil passages 34 and 35 communicating with the hydraulic oil discharge pipe 20 and an annular oil passage 36 communicating with the hydraulic oil supply pipe 18 of the oil pump 17 are formed, and the chamber 2 of the reaction force plunger 27 is formed.
An annular oil passage 38, which communicates with the hydraulic oil supply / discharge pipe 37, and an oil passage 39, which communicates the annular oil passages 36, 38 with each other, are formed in the shaft 9. Therefore, in the demagnetized state of the solenoid 33, the spool 31 is at the lowered position, the hydraulic oil supply pipe 18 and the annular oil passage 36 are in communication, and the hydraulic oil is pumped by the oil pump 17.
Is supplied to the hydraulic control valve 28 from the hydraulic oil supply pipe 18, and is supplied from the annular oil passage 36 to the chamber 29 of the reaction force plunger 27 through the oil passage 39 and the annular oil passage 38.
On the other hand, in the energized state of the solenoid 33, the spool 31 is in the raised position, the hydraulic oil supply pipe 18 and the annular oil passage 36 are not communicated, and the hydraulic oil is not supplied to the hydraulic control valve 28.

The hydraulic control valve 28 as described above is controlled by a control unit (CU) 51. That is, a vehicle speed sensor 41, a steering angle sensor 52, a steering force sensor 53, an engine speed sensor 42, etc. are connected to the control unit 51.
The control unit 51 has a lateral acceleration calculator 54, a fatigue coefficient calculator 55, and a fuzzy calculator 56 that sets a target assist amount by fuzzy calculation. Then, in the control unit 51, the lateral acceleration calculating unit 54 calculates the lateral acceleration G _Y generated in the vehicle based on the vehicle speed V input from the vehicle speed sensor 41 and the steering angle ha input from the steering angle sensor 52. Further, the lateral acceleration calculation unit 54 multiplies the vehicle speed V by the calculated lateral acceleration G _Y to obtain a calculation value V · G _Y, which is output to the fuzzy calculation unit 56.

Further, the fatigue coefficient calculating section 55 is based on the vehicle speed V input from the vehicle speed sensor 41, the steering angle ha input from the steering angle sensor 52, and the steering force hf input from the steering force sensor 53. Fatigue coefficient K acting on the driver
_{The w} is obtained and output to the fuzzy calculation unit 56. The fuzzy calculation unit 56 uses the vehicle speed V input from the vehicle speed sensor 41, the calculated value V · G _Y input from the lateral acceleration calculation unit 54, and the fatigue coefficient K _w input from the fatigue coefficient calculation unit 55 to fuzzy. Calculation is performed, the calculation result is output to the hydraulic control valve 28, and the amount of current supplied to the solenoid 33 is set to control the solenoid 33.

In the fuzzy calculation section 56, as shown in FIG. 7, a membership function for obtaining the degree of conformity (grade) from the vehicle speed V with respect to the running state, and as shown in FIG.
By applying a membership function for obtaining a goodness of fit regarding the calculated value V · G _Y obtained by multiplying the vehicle speed V by the lateral acceleration G _Y , and a membership function for obtaining a goodness of fit regarding the fatigue coefficient K _w as shown in FIG. , The suitability of the vehicle speed V, the suitability of the calculated value V · G _Y , and the suitability of the driver's fatigue coefficient K _w in the traveling state of the vehicle, respectively. As shown in FIG. 10, the control amount, that is, the steering assist amount is determined from the graph showing the base set based on these conformances, and the amount of current supplied to the solenoid 33 is controlled. .

In this embodiment, the traveling state is divided into three stages as shown in FIG. 7 as a membership function of the vehicle speed V, and the vehicle speed V is 0 to 75 km / h in the "low speed traveling mode".
30 to 120km / h in "medium speed driving mode", 75km / h
The above is set as the “high-speed traveling mode”, and the suitability for these modes is determined corresponding to the vehicle speed V. On the other hand, as shown in FIG.
It is divided into stages and is set as "S (small)", "M (medium)", and "B (big)". The evaluation amount is 100% and the evaluation amount is 0%. I am trying.

For the low speed running mode of the membership function of the vehicle speed V, the assist control amount evaluation S, and
Evaluation M corresponds to the medium speed running mode, and evaluation B corresponds to the high speed running mode. That is, the rule is set such that when the vehicle speed V increases, the steering assist amount is reduced and the steering wheel is made heavier.

Further, as shown in FIG. 8, the traveling state is shown as a membership function of the calculated value V · G _Y obtained by multiplying the vehicle speed V by the lateral acceleration G _Y , and the calculated value V · G _Y is 0 to 100 Gkm / h.
Until the area, fitness is increased linearly according to the increase of the calculated value V · G _Y, the operation value V · G _Y is 100Gkm / h or more areas, regardless of the increase of the calculated value V · G _Y The suitability is set to be constant. And this calculated value V
The membership function of G _Y corresponds to the evaluation B of the assist control amount according to the degree of conformity. That is, the calculated value V
・ We set a rule to reduce the steering assist amount and make the steering wheel heavier when G _Y rises.

Furthermore, as shown in FIG. 9, the running state is shown as a membership function of the driver's fatigue coefficient K _w , and as shown in FIG. 9, the fatigue coefficient K _w increases until the fatigue coefficient K _w is in the range of 0 to 1. Accordingly, the goodness of fit decreases linearly, and the goodness of fit is set to be constant at 0 in a region where the fatigue coefficient K _w is 1 or more. The membership function of the fatigue coefficient K _w corresponds to the evaluation S of the assist control amount according to the fitness. That is, the rule is set such that when the fatigue coefficient K _w decreases, the steering assist amount increases and the steering wheel becomes lighter.

From the goodness of fit of the vehicle speed V, the goodness of fit of the calculated values V · G _Y , and the goodness of fit of the fatigue coefficient K _w , the center of gravity method is used by using the graph of the calculation process shown in FIG. The target assist amount can be obtained.

Here, the method of calculating the fatigue coefficient K _w by the fatigue coefficient calculator 55 will be described with reference to the flowcharts of FIGS. 11 and 12. As shown in FIGS. 11 and 12, the process of the fatigue coefficient calculation is started by turning on the ignition, and in step M1,
The vehicle speed V from the vehicle speed sensor 41, the steering angle ha from the steering angle sensor 52, and the steering force hf from the steering force sensor 53 are read, and the routine proceeds to step M2. In step M2, it is determined whether the vehicle speed V is 30 km / h or more and the steering angle ha is 10 deg or more, and if so, the driver determines that the vehicle is traveling and the process proceeds to step M3. .
Then, in step M3, the steering angular velocity ha 'is calculated from the following equation based on the steering angle ha. ha ′ = | ha _n −ha _n−1 | / t Note that this calculation is performed every 50 milliseconds. Then, in step M4, the steering work amount W is calculated from the following equation based on the steering angular velocity ha 'and the steering force hf. W = ha '× hf

In step M5, the steering work amount W obtained in step M4 is accumulated, and in step M6, the reference value timer T _ws starts counting up. Then, in step M7, it is determined whether or not the count value of the reference value timer T _ws has reached 30 minutes. That is, the reference value W _s of the steering wakefulness is calculated based on the change in the steering work amount W for 30 minutes after the driver starts driving the vehicle,
If T _ws = 30, the process _proceeds to step M8. Then, in step M8, the steering work amount W in 30 minutes
The reference value W _s of the steering wakefulness is obtained from the following equation by calculating the average value of W _s = W _30/30

On the other hand, in step M7, if the count value of the reference value timer T _ws is not 30 minutes, step M10
Then, the detected value W _d of the steering awakening degree of the driver who is driving the running vehicle is obtained by the following process. That is, in step M10, the steering work amount W obtained in step L3 is accumulated, and in step M11, the detection value timer T _wd starts counting up. Then, in step M12, it is determined whether the count value of the detection value timer T _wd has reached 5 minutes. That is, the detected value W _d of the steering wakefulness is calculated based on the change in the steering work amount W every 5 minutes after the driver starts driving the vehicle, and T _wd =
If it is 5, the process proceeds to step M13. Then, in step M13, the detected value W _d of the steering awakening degree is obtained from the following equation by calculating the average value of the steering work amount W in 5 minutes. W _d = W _5/5 Then, the count value of the reference value the timer T _wd to 0 at step M14, the cumulative value W ₅ of 5 minutes of the steering work amount W in step M15 to 0.

Then, in step M16, the step
Reference value W determined by M8_s(30 minutes of steering work W
Average value of₃₀/ 30) and the detection obtained in step M13
Value W _d(The average value W of the steering work amount W for 5 minutes_Five/ 5) with
Ratio (W_d/ W_s) To the fatigue factor K_wTo calculate.

In step M16, steering awakening
Degree reference value W_sAnd detection value W_dAnd the fatigue factor K_w
Is calculated, but the reference value W of the steering wakefulness_sThe driver is a car
It is calculated 30 minutes after starting both operations.
This is a value that was not required before that. Therefore,
Less than 30 minutes after the driver starts driving the vehicle (T _ws
Up to <30), the standard value W of the steering alertness_sGeneral number to
Is given, the reference value W of the steering alertness_sCalculation of (W_s=
W₃₀/ 30) and then rewrite
It However, 30 minutes after the driver starts driving the vehicle
The driver's alertness is high until
It is not necessary to judge the rudder awakening degree.

The control procedure of the control unit 51 in the above-described electronically controlled power steering apparatus of this embodiment will be described with reference to the flow chart of FIG.

As shown in FIG. 13, first, step S1
At the vehicle speed sensor 41, the traveling speed V of the traveling vehicle is detected.
Is detected, the sensor signal of the vehicle speed is output to the CU 51 (the lateral acceleration calculation unit 54 and the fuzzy calculation unit 56), and step S
Move to 2. In step S2, the steering angle sensor 5
2 detects the steering angle ha of the vehicle and outputs the sensor signal of the steering angle to C
U51 (lateral acceleration calculation unit 54, fatigue coefficient calculation unit 55)
Output to. Further, in step S3, the steering force sensor 53 detects the steering force hf of the vehicle, outputs a sensor signal of the steering force to the CU 51 (fatigue coefficient calculation unit 55), and proceeds to step S4. In step S4, the CU 51 converts an analog signal as a sensor signal of the vehicle speed V and the steering angle ha into a digital signal, and the lateral acceleration calculating unit 54 processes the vehicle speed V.
The lateral acceleration G _Y occurring in the vehicle is calculated based on the steering angle ha and the steering angle ha. Further, in step S5, the vehicle speed V is changed to the lateral acceleration G
_Y is multiplied to obtain the calculated value V · G _Y.

Further, in step S5, the CU 51 converts the analog signal as the sensor signal of the steering force hf into a digital signal, and the fatigue coefficient calculating unit 55 performs the steering force hf.
Based on the above, the driver's fatigue coefficient K _w is calculated.

Then, in step S7, the fuzzy operation unit 56 obtains the degree of conformity with respect to the traveling state of the vehicle speed V from the graph of the membership function shown in FIG.
Seeking fit about the traveling state of the operation value V · G _Y from the graph of the membership function shown in, goodness of fit about the traveling state of fatigue coefficient K _w from the graph of the membership function shown in FIG. Then, in step S8, a target assist amount is determined by the center of gravity method from the respective degrees of conformity using the graph of the arithmetic processing shown in FIG. Furthermore,
In step S9, this target assist amount is converted into a current amount to be applied to the solenoid 33 of the corresponding hydraulic control valve 28, and in step S10, this current amount for controlling the steering assist amount is converted into the drive circuit, that is, the hydraulic control valve 28.
To the solenoid 33.

Here, the fuzzy control in a concrete running state of the vehicle will be described based on the calculation process for obtaining the assist amount by the center of gravity method shown in FIG. For example, consider a situation where the vehicle speed V is turning at 60 km / h. In this case, the lateral acceleration G _Y when the vehicle is turning at a vehicle speed V of 60 km / h is 0.2 G, and the fatigue coefficient K _w is 0.5.

Therefore, when the vehicle speed V is 60 km / h, the compatibility in the medium speed traveling mode is 0.67 and the compatibility in the low speed traveling mode is 0.33, which is the assist control amount corresponding to the medium speed traveling. Is evaluated as M, and the assist control amount corresponding to low speed traveling is evaluated as S. The lateral acceleration G _{Y at} this time is 0.2 G, and the calculated value V · G _Y obtained by multiplying the vehicle speed V (60 km / h) by the lateral acceleration G _Y (0.2 G) is 12 Gkm.
/ H, and the compatibility becomes 0.12. Further, the fatigue coefficient K _{w at} this time is 0.5, and the fitness is 0.5.

Then, from the conformity of the vehicle speed V, the calculated value V · G _Y , and the fatigue coefficient K _w thus obtained, the center of gravity method is used, that is, the center of gravity of the total area corresponding to the conformity is obtained and the target is obtained. And determine the amount of assistance. That is, in the turning traveling state where the vehicle speed V is 60 km / h, the evaluation of the assist control amount relating to the vehicle speed V is M, the degree of conformity is 0.67, and the evaluation S is the degree of conformity, which is 0.33. Value V
The evaluation of the assist control amount relating to G _Y is B, the degree of conformity thereof is 0.12, and the evaluation of the assist control amount regarding the fatigue coefficient K _w is S, and the degree of conformity thereof is 0.5. Therefore, the assist amount is 64%.

As described above, when the vehicle is turning at the vehicle speed V = 60 km / h, the vehicle speed V is high, but the lateral acceleration G _Y increases. Therefore, generally, the steering assist amount of the power steering slightly increases. The steering wheel is slightly heavy. However, at this time, since the driver's fatigue degree coefficient K _w is high, the driver is tired, and the steering wheel feels heavy and becomes a burden. Thus, in this embodiment, by applying the fatigue factor K _w drivers obtained based on the steering force speed hf 'handles the driver operates as a membership function, the driver continuously operated around the clock When the fatigue accumulates, the steering assist amount of the power steering is increased by increasing / decreasing the fatigue coefficient K _w to make the steering wheel slightly lighter than usual.

As described above, in the electronically controlled power steering system of this embodiment, in addition to the increase / decrease in vehicle speed V, the fatigue coefficient K _w is applied as a membership function,
Since the steering assist amount is controlled by fuzzy reasoning corresponding to these membership functions, the fatigue amount coefficient K _w increases when the driver is fatigued, so the assist amount increases, and the steering wheel is moved by this amount. It gets lighter. Therefore, even if the vehicle is traveling at a high speed to some extent, when the driver is tired, the steering force of the steering wheel is reduced and the driver can easily steer the vehicle.

Further, the electronically controlled power steering of this embodiment
In the ring device, the vehicle speed V is increased by the lateral acceleration G._YMultiply by
Calculated value V / G_YAs a membership function,
By fuzzy reasoning corresponding to these membership functions
The steering assist amount is controlled by the
Lateral acceleration G_Y(Steering angle) is large
As a result, the degree of decrease in the amount of assist increases,
The handle becomes heavy. Therefore, even if the vehicle speed is different
When entering a corner, the driver should always
You can maneuver while feeling the approach with the steering wheel. Well
Lateral acceleration G _YThis lateral addition to the membership function for
Speed G_YSteering linear whose fitness changes linearly with respect to
Since the steering area is provided, the steering linearity
Reserved.

Further, in the electronically controlled power steering system of this embodiment, the calculated value V · G _Y obtained by multiplying the vehicle speed V and the lateral acceleration G _Y is applied as the membership function for controlling the steering assist amount. Therefore, when the vehicle is traveling at a high speed, the vehicle speed V is sufficiently high even if the steering angle decreases and the lateral acceleration G _Y decreases, so that the calculated value V · G _Y does not decrease significantly, and the target assist amount increases significantly. There is no significant increase and the handle is not so light. Therefore, the feeling of steering operation when the vehicle is traveling at high speed is sufficiently maintained, and the stability of steering operation of the steering wheel is improved.

Further, in the electronically controlled power steering system of this embodiment, the "vehicle speed V
Is increased, the steering assist amount is reduced and the steering wheel is made heavier, the rule that “the steering assist amount is reduced and the steering wheel is made heavier when the calculated value V · G _Y is increased”, and the fatigue factor K By controlling the steering assist amount based on three rules that "the steering assist amount is increased and the steering wheel is lightened when _w is decreased", it is possible to perform finer control with a small number of rules.

Although the control system of the electronically controlled power steering device has been described as a hydraulic system in the above-described embodiments, the present invention is not limited to this, and an electric power steering device using a motor can be used. Even if it is applied, the same effect can be obtained, and the mechanical system of the electronically controlled power steering device is not limited to the above-mentioned embodiment, and it can be applied to any of them. Is something that can be done.

In the above embodiment, the controller
The lateral acceleration calculation unit 54 is provided in the
The vehicle speed V input from the vehicle speed sensor 41 by the speed calculator 54
And the steering angle ha input from the steering angle sensor 52
Lateral acceleration G generated in the vehicle_YWas calculated,
This lateral acceleration G _Y
May be measured directly. Furthermore, vehicle speed V and lateral
Acceleration G_YCalculated value V / G_Y, Fatigue factor K_wMember of
Ship function and steering assist amount are each evaluated by 3
Although it is divided into stages, five stages may be used, for example. And this
The steering assist amount was calculated by the center of gravity method.
Even if calculated by the height method (skeleton method), area method, etc.
It's good.

Further, in the above embodiment, the control unit (target assist amount setting means) 51 sets the target assist amount based on the fuzzy rule.
The target assist amount may be set based on other control means.

[0088]

As described above in detail with reference to the embodiments, according to the wakefulness determining device of the present invention, the steering angle detecting means detects the steering angle of the steering mechanism of the vehicle while the vehicle is running and the steering is performed. The force detection means detects the steering force of the steering mechanism of the running vehicle, and the steering wakefulness calculation means calculates the average value of the steering work amount for each predetermined time based on the detection results of the steering angle detection means and the steering force detection means. Since the steering wakefulness is calculated and the steering wakefulness determining means compares the steering wakefulness obtained by the steering wakefulness calculating means with a preset reference value to determine a decrease in the wakefulness, There is no need to install a detection device such as a heart rate sensor that interferes with the steering device by the driver, and an average value for a predetermined time is calculated based on the steering force of the steering mechanism and compared with a reference value. It is possible to determine the driver's steering arousal level from the knowledge, and regardless of the driver's driving posture, and without annoying the driver, the driver's health condition can be accurately grasped and accurately measured. Arousal level can be determined.

According to the electronically controlled power steering apparatus of the present invention, the vehicle speed detecting means detects the traveling speed of the vehicle, and the steering angle detecting means detects the steering angle of the steering mechanism and the steering force detecting means. Detects the steering force, and the fatigue coefficient calculation means compares the steering awakening degree calculated from the average value of the steering work amount calculated for each predetermined time based on the steering angle and the steering force with a preset reference value. Then, the driver's fatigue level coefficient is calculated, and the target assist amount setting means sets the target assist amount by using the traveling speed of the vehicle and the driver's fatigue level coefficient as input conditions. The steering force can be controlled according to the situation, the steering feeling can be improved, the optimum steering characteristics can be obtained according to the driver's fatigue state, and the driving condition can be changed. By using the fatigue coefficient, it is possible to improve the ease of steering operation when fatigue is accumulated in the driver.

Further, according to the electronically controlled power steering apparatus of the present invention, the target assist amount setting means sets the target assist amount based on the fuzzy rule with the running speed of the vehicle and the driver's fatigue coefficient as input conditions. As a result, fine steering control can be performed with a small number of rules, and a steering feeling that balances a sense of stability and ease of handling depending on the vehicle speed and fatigue can be obtained, and steering linearity can be increased to help the driver It becomes possible to grasp the traveling situation and improve the steering performance.

Further, according to the electronically controlled power steering system of the present invention, the target assist amount setting means has a membership function for evaluating the traveling speed of the vehicle and a membership function for evaluating the fatigue factor of the driver. The target assist amount is set based on a fuzzy rule that increases the target assist amount as the vehicle traveling speed decreases and reduces the target assist amount as the driver's fatigue coefficient increases. By increasing the steering assist amount in accordance with the decrease in the vehicle speed and the fatigue factor, the steering force characteristic becomes lighter as the vehicle speed becomes lower and the driver accumulates fatigue, and the steering feeling becomes easier. A sense of stability can be obtained.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic structure of a vehicle drowsiness alarm device having a wakefulness determination device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an external appearance of a vehicle compartment in this embodiment.

FIG. 3 is a flowchart showing a flow of processing for determining a driver's steering alertness.

FIG. 4 is a flowchart showing a processing flow of a driver's steering alertness calculation.

FIG. 5 is a flowchart showing a processing flow of a driver's steering alertness calculation.

FIG. 6 is a schematic configuration diagram of a power steering hydraulic control unit according to an embodiment of an electronically controlled power steering device of the present invention.

FIG. 7 is a graph showing a membership function of vehicle speed used for fuzzy control.

FIG. 8 is a graph showing a membership function of vehicle speed × lateral acceleration used for fuzzy control.

FIG. 9 is a graph showing a membership function of a fatigue coefficient used for fuzzy control.

FIG. 10 is a graph showing a calculation process for obtaining the power steering assist amount from the fitness of each membership function by the center of gravity method.

FIG. 11 is a flowchart showing a flow of processing for calculating a fatigue coefficient.

FIG. 12 is a flowchart showing the flow of processing for fatigue factor calculation.

FIG. 13 is a flowchart showing fuzzy control.

FIG. 14 is an explanatory diagram showing a specific control example of a calculation process for obtaining an assist amount from the membership functions of vehicle speed, vehicle speed × lateral acceleration, and fatigue coefficient, by the center of gravity method.

FIG. 15 is a schematic configuration diagram of a power steering hydraulic control unit representing an example of a conventional electronically controlled power steering device.

16 is a sectional view taken along line XVI-XVI of FIG.

17 is a sectional view taken along line XVII-XVII in FIG.

[Explanation of symbols]

 11 Input Shaft 12 Casing 13 Pinion Gear 14 Torsion Bar 15 Rack 16 Rotary Valve 17 Oil Pump 19 Oil Reservoir 21 Hydraulic Cylinder 25, 26 Oil Chamber 27 Reaction Force Plunger 28 Hydraulic Control Valve 29 Chamber 31 Spool 33 Solenoid 41 Vehicle Speed Sensor 51 Control Unit ( CU) 52 steering angle sensor 53 steering force sensor 54 lateral acceleration calculation unit 55 fatigue factor calculation unit 56 fuzzy calculation unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B62D 119: 00 127: 00 137: 00

Claims (4)

[Claims] 1. A steering angle detecting means for detecting a steering angle of a steering mechanism of a traveling vehicle, a steering force detecting means for detecting a steering force of a steering mechanism of a traveling vehicle, the steering angle detecting means and steering. Based on the detection result of the force detection means, the steering wakefulness calculation means for calculating the average value of the steering work amount for each predetermined time to obtain the steering wakefulness and the steering wakefulness calculated by the steering wakefulness calculation means A wakefulness determination device, comprising: steering wakefulness determination means for determining a decrease in wakefulness by comparing with a preset reference value. 2. An electronically controlled power steering device for electronically controlling a steering assist amount in a steering mechanism of a vehicle, a vehicle speed detecting means for detecting a traveling speed of the vehicle, and a steering angle detecting means for detecting a steering angle of the steering mechanism. And steering force detection means for detecting the steering force of the steering mechanism, and steering awakening obtained from the average value of the steering work amount for each predetermined time calculated based on the detection results of the steering angle detection means and the steering force detection means. Degree is compared with a preset reference value to calculate a fatigue degree coefficient of the driver, and a target assist amount is set by using the traveling speed of the vehicle and the fatigue degree coefficient of the driver as input conditions. An electronically controlled power steering device comprising a target assist amount setting means. 3. An electronically controlled power steering device for electronically controlling a steering assist amount in a steering mechanism of a vehicle, a vehicle speed detecting means for detecting a traveling speed of the vehicle, and a steering angle detecting means for detecting a steering angle of the steering mechanism. And steering force detection means for detecting the steering force of the steering mechanism, and steering awakening obtained from the average value of the steering work amount for each predetermined time calculated based on the detection results of the steering angle detection means and the steering force detection means. Degree calculation means for calculating the driver's fatigue degree coefficient by comparing the degree with a preset reference value, and a target based on the fuzzy rule with the vehicle speed and the driver's fatigue degree coefficient as input conditions. An electronically controlled power steering device comprising: a target assist amount setting means for setting an assist amount. 4. The electronically controlled power steering system according to claim 3, wherein the target assist amount setting means includes a membership function for evaluating the traveling speed of the vehicle and a membership function for evaluating the driver's fatigue coefficient. The target assist amount is set based on a fuzzy rule in which the target assist amount is increased as the traveling speed of the vehicle is decreased and the target assist amount is increased as the driver's fatigue coefficient is decreased. An electronically controlled power steering device characterized in that