JPH0396439A - Kinetic characteristics control device for vehicle - Google Patents

Abstract

PURPOSE:To realize optimum kinetic characteristics to ensure the safety of travelling of a vehicle by detecting driver's states such as a napped state, a fatigued state, a strained state, etc., to change the kinetic characteristics of the vehicle based on operations of the driver. CONSTITUTION:A microcomputer 25 receives state-signals of a driver from a front wheel steering angle sensor 19, a handle pressure sensor 23 for detccting handle gripping pressure of the driver, further receives the number of heartbeats detected by a sensor 27 through a transmitter 26 and a receiver 24, and detects driver's state such as a napped state, a fatigued state, a strained state, etc. In accordance with the detection, a buzzer 29 provides a warning, and actuators 11a-14a are controlled to enhance the damping force of a shock absorber and restrict the change in position of a vehicle due to handle steering. Further, the actuators alter steering characteristics, steering reaction force, steering ratio, steering angle ratio between rear wheels and front wheels. The safety of travelling of the vehicle can thus be ensured.

Description

[Detailed description of the invention]

['m Industrial Application Field 1] The present invention relates to a control device for automatically controlling the motion characteristics of a vehicle, and particularly to a control device for controlling the motion characteristics of a vehicle in which the control is performed using a man-machine control method. Regarding equipment. [Prior Art] Conventionally, for example,
As shown in the publication, the present invention includes a dozing state detection means for detecting the dozing state of the driver from the steering pattern of the vehicle,
If the drowsy state is detected while the vehicle is in a constant speed driving mode in which the vehicle travels at a constant speed at a set speed regardless of whether the accelerator pedal is depressed, the constant speed driving mode is canceled and the vehicle is accelerated. There are some models that activate the horn at the same time as returning to normal driving mode corresponding to pedal operation. According to this, the constant speed driving mode is automatically canceled and the engine brake is activated. Since the W warning sound is pronounced, the attention of N-turners is called to attention. [Problems to be Solved by the Invention] However, the above-mentioned conventional device only arouses the consciousness of the driver who is dozing off, and does not affect the driving state of the vehicle based on the operation of the driver who is dozing off, and the above-mentioned effects. There is no consideration given to the effect on the driving state of the vehicle based on the driver's operations due to surprise immediately after the awakening of consciousness due to arousal, and it is extremely inadequate as a control for a man-machine system consisting of the driver and the vehicle. be. The present invention has been made in order to take the above-mentioned man-machine system control one step further, and its purpose is to optimize the vehicle for driving operations by matching the driver's condition and the vehicle's motion characteristics in response to the driver's operation. An object of the present invention is to provide a motion characteristic control device for a vehicle that can realize the motion characteristics and ensure safe running of the vehicle and ensure ease of driving the vehicle. [Means for Solving the Problems] In order to achieve the above object, the present invention provides a structure of a vehicle dynamic characteristic control device or a dynamic characteristic changing device capable of changing vehicle dynamic characteristics based on a driver's operation. a driver condition detecting means for detecting the condition of the driver; and a vehicle based on the operation of the driver by controlling the motion characteristic changing device according to the condition of the driver detected by the driver condition detecting means. a of
and change control means for changing the driving characteristics according to the condition of the driver.

Effect of the Invention In the present invention configured as described above, the driver's condition such as a dozing state, a fatigued state, a nervous state, etc. is detected by the driver state detecting means while the vehicle is running, and the driver's state is detected by the driver state detecting means. In response to this, the change control means controls the dynamic characteristic changing device to change the dynamic characteristic of the vehicle based on the driver's operation in accordance with the detected state of the driver. In such a case, more specifically, the motion characteristic changing device is, for example, configured with a shock absorber installed in the suspension system and capable of changing the damping force, and is configured to change the dynamic characteristics when the driver is asleep, fatigued, or nervous. At times, the damping force of the absorber is changed to a higher value to suppress changes in the attitude of the vehicle when the vehicle turns due to steering wheel steering. The dynamic characteristic changing device is, for example, a steering characteristic changing mechanism that is installed in the suspension system and can change the steering characteristic (understeer and oversteer) when the vehicle turns, and is configured to change the steering characteristic when the driver is in each of the above states. In this case, the steering characteristic is switched to the understeer side. The motion characteristic changing device is, for example, a power steering device that is installed in a steering device and can change the steering reaction force, and when the driver is in each of the above states, the steering reaction force is increased. (The steering assist force is weakened) and the steering wheel operation becomes heavier, and the vehicle turning characteristics in response to the steering wheel operation are changed. In addition, the motion characteristic changing device is, for example, configured with a steering ratio changing mechanism that is installed in the steering device and can change the steering ratio (steering wheel steering ffi/front wheel turning angle), and is configured to change the steering ratio when the driver is in each of the above states. By setting the steering ratio to a large value, the front wheel steering angle relative to the steering wheel steering angle is changed to a smaller side, and the turning response of the vehicle to the steering operation is slowed down. Further, the dynamic characteristic changing device is, for example, a rear wheel steering device that is installed in a four-wheel steering vehicle and can change the steering angle ratio (rear wheel steering angle/front wing steering angle), and In such a state, the steering angle ratio is switched to the in-phase side, and the turning response of the vehicle to the steering operation is slowed down. Effect 1 of the Invention As is clear from the above description of the operation, according to the present invention, the dynamic characteristics of the vehicle based on the driver's operation can be sharply adjusted depending on the driver's state such as a dozing state, a fatigue state, a nervous state, etc. Since the driver's condition can be made more or less dull, it is possible to match the driver's condition with the motion characteristics of the vehicle in response to the driver's operations, and it becomes possible to realize the optimal vehicle motion characteristics in response to the driver's operation. This makes it possible to ensure safe driving of the vehicle and to ensure ease of driving the vehicle. Embodiments a6 First Embodiment An example in which the present invention is applied to a vehicle equipped with a suspension system capable of changing damping force will be described with reference to the drawings. Figure 1 shows each wheel FWI, FW2, RWI, RW2 (
However, the entire vehicle is schematically shown in which shock absorbers l1 to l14 constituting the dynamic characteristic changing device of the present invention are provided in each suspension system that suspends wheels FW2 and RW2 (not shown). . The shock absorbers 11 to 14 are mounted on the vehicle body B, as shown in FIGS.
It is provided between the wheel side member and the vehicle body BD so as to pass through the coil springs 15 to 18 that elastically support the wheel D to each wheel FWI, FW2, RWI, RW2, and inside thereof , an electromagnetic actuator that controls the damping force by switching the valve opening of the oil passage into three stages: "high", "medium J", and "low".
14a, respectively. These electromagnetic actuators 11a''l4a are controlled according to the driver's operation, the vehicle condition, and the driver's condition, and the vehicle has a front wheel steering angle sensor 19 to detect the operation and each condition. , a throttle opening sensor 20, a brake switch 21, a vehicle speed sensor 22, a steering wheel pressure sensor 23, and a receiver 24.
It is equipped with a microcomputer 25 that controls 4a. The front wheel steering angle sensor 19 is assembled on the outer periphery of the steering shaft connected to the steering handle WH, and outputs a detection signal representing the steering angle of of the front wheels FWI, FW2 by detecting the rotation angle from the coaxial reference position. . The throttle opening sensor 20 is attached to the rotating shaft of the throttle valve, and outputs a detection signal representing the depression operation amount SLT of the accelerator pedal by detecting the rotation angle from the coaxial reference position. The brake switch 21 is constituted by a switch that operates in conjunction with the brake pedal, and outputs a detection signal indicating whether or not the brake pedal is depressed. The vehicle speed sensor 22 is composed of a rotation speed sensor that detects the rotation speed of the output shaft of the transmission, and outputs a detection signal representing a vehicle speed V that is proportional to the rotation speed. The steering wheel pressure sensor 23 is provided on the outer periphery of the steering wheel WI-1 so as to cover the steering wheel WH, and outputs a detection signal representing the pressure HGP at which the driver grips the steering wheel WH. The receiver 24 receives and outputs a transmission signal representing the driver's heart rate transmitted wirelessly from the transmitter 26. This transmitter 26 wirelessly transmits a detection signal representing the driver's heart rate detected by a heart rate sensor 27 connected to the transmitter 26. For example, the transmitter 26 is built in a wristwatch, a bracelet, etc. It is also attached to a part of the driver's body. The microcomputer 25 has ROMs 25b. CPU25c, RAM25d
, an input port 25e, and an output port 25f. R
The OM 25b stores programs corresponding to the flowcharts in FIGS. 3 and 4, the CPU 25c executes the programs, and the RAM 25d temporarily stores variable data necessary for executing the programs. Input port 25e
is connected to each of the sensors 19 to 24, etc., and inputs each detection signal. The output port 25f outputs a control signal for controlling the electromagnetic actuators lla~14a, and the output port 25f outputs a control signal for controlling the electromagnetic actuators lla~14a.
A drive circuit 28 is connected between the drive circuit 14a and the drive circuit 14a. Further, a buzzer 29 that generates a warning sound to the driver is connected to the output port 25f. Next, jl!, which was organized as above! The operation of one embodiment will be explained with reference to the flowchart in FIG. When the ignition switch (not shown) is closed, the CPU 25c starts executing the program at step 100 in FIG. 3, and performs initialization necessary for executing the program at step 102. After the ignition switch is opened, steps 104-
124 continues to be executed. During this W ring processing, in step 104, the front wheel steering angle of and throttle opening sLT are input as driver operation signals.
Detection signals indicating the presence or absence of the brake pedal depression operation BSW are input from the front wheel steering angle sensor 19, the throttle opening sensor 20, and the brake switch 21 to the input boat 2.
5e, and in step 106, a detection signal representing the vehicle speed V is sent to the vehicle speed sensor 2 as a vehicle status signal.
2 through the input port 25e. next,
In step 108, each detection signal representing the front wheel steering angle of, the pressure HGP of gripping the steering wheel WH, and the heart rate BPN is detected as the driver's status signal by the front wheel steering angle sensor 19,
It is read from the handle pressure sensor 23 and the receiver 24 through the input port 25e. Note that the value read as the driver's operation signal in step 104 may be used as the front wheel steering angle of as the driver's status signal.
In steps 104 to 108, not only the current value but also a plurality of past values over a certain period of time are stored in the RAM 25d in chronological order. After each detection signal is input, a driver state determination routine is executed in step 110. The process of this driver condition determination routine is to determine whether the driver is in an abnormal condition such as dozing off, fatigued, or nervous, or in a normal condition, and is shown in detail in the flowchart in Figure 4. As shown in FIG. 2, the execution is started at step 150, and the driver's state determination processing is performed at steps 152 to 156. In step 152, it is determined whether a series of temporal changes in the front wheel steering angle Of from the past to the present match a specific pattern (drowsy pattern). this is,
When the driver falls asleep, it is based on the vehicle meandering in a specific pattern, and when the temporal change in the front wheel steering angle of matches the specific pattern, the driver falls asleep, that is, in an abnormal state. It is determined that there is
At other times, it is determined that the driver is in a normal state. In step 154, based on the pressure HGP of gripping the steering wheel WH within a predetermined period of time from the past to the present,
It is determined whether the pressure HGP remains below a predetermined value for a predetermined period of time. This is based on the fact that when the driver falls asleep or is fatigued, the pressure in gripping the steering wheel WH decreases, and the pressure HGP remains below a predetermined value for a predetermined period of time. At this time, it is determined that the driver is dozing off or in a fatigued state, that is, in an abnormal state, and at other times, it is determined that the driver is in a normal state. In step 156, it is determined whether the heart rate BPN has suddenly changed based on the heart rate BPN from the past to the present. This is based on the fact that when a driver is extremely nervous, their heart rate BPN increases rapidly.
When the heart rate BPN suddenly changes, it is determined that the driver is in an extremely tense state, that is, in an abnormal state; otherwise, it is determined that the driver is in a normal state. If it is determined that the driver is normal through the processing in steps 152 to 156, step 1 is performed.
If the driver status flag DSF is set to II O''' in step 58 and it is determined that the driver is abnormal,
At step 160, the driver status flag DSF is set to "1". After processing steps 158 and 160,
At step 162, execution of the driver condition determination routine is terminated, and the program proceeds to step 112 in FIG. 3. In step \112, the driver status flag D
It is determined whether the SF is "II O" or not. Now, the driver's condition is normal and the flag DSF is "0".
”, based on the determination of “YESJ” in step 112, in step 114 the driver’s operation signal of,
The behavior of the vehicle is determined according to the SLT, BSW, and vehicle status signal V, and a damping force flag ADF for setting the damping force of the shock absorbers 1 to 14 is set as follows according to the determination. be done. (2) When the front wheel steering angle θ exceeds a predetermined amount, it is determined that the vehicle starts turning, and the damping force flag ADF is set to "2" representing "high" damping force for a certain period of time. ■When the throttle opening SLT (accelerator pedal depression amount) or the increasing speed of the throttle opening SLT (accelerator pedal depression speed) exceeds a predetermined value, it is determined that the vehicle has started accelerating, and the damping force flag is flagged. The ADF is set to "2" representing "high" damping force for a certain period of time. (2) When the data BSW indicates a depression operation of the brake pedal, it is determined that the vehicle starts decelerating, and the damping force flag ADF is set to "2" representing "high" damping force for a certain period of time. ■When the vehicle speed■ is higher than the predetermined vehicle speed, the damping force flag AD
F is set to "1" representing "medium" damping force. ■ In cases other than the above ■ - ■, the damping force flag ADF is set to "O IF", which indicates "low" damping force. After the process of step 114, the set damping force flag ADF is set in step 116. The program will step 11 depending on the value.
You can proceed from 8 to 122. That is, the damping force flag AD
If F is IT O”, the program goes to step 118.
At step 118, a control signal representing the damping force "low J" is outputted to the deactivation circuit 28 via the output port 25f. If the damping force flag ADF is +11++,
The program advances to step 120, where step 1
At 20, a control signal indicating "damping force r medium" is output to output port 25.
It is output to the drive circuit 28 via f. If the damping force flag ADF is "2", the program proceeds to step 122, and in the same step l22, an ilJ control signal representing "high" damping force is output to the lipostatic circuit 28 via the output port 25f. The drive circuit 28 controls the W1 magnetic actuators lla to 14a to move according to the control signals, and adjusts the damping force of the shock absorbers 11 to 14 according to the control signals.
Control settings for low, medium, and high. As a result, when the vehicle is traveling at high speed or the behavior of the vehicle changes, the damping force of shock absorbers 1 to 14 is set to the higher side, and the amount of change in attitude of the vehicle is reduced. Since the direction is controlled, the vehicle's steering stability is maintained well. In addition, when the vehicle is running normally, the damping force of shock absorbers 1 to 4 is set to the low side, and the vehicle is controlled in a direction that reduces the impact on the occupants due to changes in posture. This improves the ride comfort of the vehicle. On the other hand, if it is determined that the driver's condition is abnormal as a result of the execution of the driver condition determination routine in step 110, the program proceeds to step 124 based on the "NO" determination in step 112. , same step 12
At step 4, a control signal for making the buzzer 29 sound is outputted to the buzzer 29 via the output port 25f. As a result, the buzzer 29 sounds for a predetermined period of time, thereby arousing the driver's awareness. After the processing in step 124, in step 122, as described above, the shock absorber 1~
The damping force of 14 is ri! {J J is set. As a result, irrespective of changes in the vehicle's behavior, when the driver is in an abnormal state, the vehicle is controlled in a direction that reduces changes in attitude with respect to vehicle behavior such as turning. As a result, even if a driver in an abnormal condition makes an incorrect steering wheel operation, the change in the vehicle's attitude in response to the steering wheel operation is reduced, so that the vehicle can deal with the driver's abnormal condition and drive in a safe direction. He will be under control. b. Second Embodiment FIG. 5 is a diagram illustrating an example in which the present invention is applied to a vehicle equipped with a suspension system capable of changing steering characteristics (understeer and oversteer) during turning.
I, FW2, RWI, and RW2 are each suspended in a hydraulic cylinder 3 in which the motion characteristic changing device of the present invention is installed.
1 to 34 are schematically shown as a whole. A pressure control valve 3 is installed in these hydraulic cylinders 31 to 34.
1a to 34a are connected to each other, and each valve 3
1a to 34a are connected to a hydraulic pump 35 and a reservoir 36, respectively. At the same time, the hydraulic pressure in the hydraulic cylinders 31 to 34 is set and controlled according to the supply control signal. This vehicle also includes a front wheel steering angle sensor 19, a vehicle speed sensor 22, a steering wheel pressure sensor 23, a receiver 24, a microcomputer 25, a transmitter 26, a heart rate sensor 27, and a buzzer 29 similar to those in the first embodiment. It is equipped with However, in this microcomputer 25,
The ROM 25b stores programs corresponding to the flowcharts shown in FIGS. 4 and 6, as well as the front-rear load distribution ratio K t r l] when the vehicle turns as shown in FIG. K t
r + is stored in the form of a table. Further, the input port 25e and the output port 25f are combined and represented as an input/output port 25g. This input/output boat 2
5g is connected to a lipid circuit 37 for controlling the pressure control valves 31a to 34a. Next, the operation of the second embodiment configured as described above will be explained with reference to the flowchart shown in FIG. In this embodiment as well, program execution is started in step 200 by closing the ignition switch, and after initialization in step 202, steps 204 to 2 are performed.
A circular process consisting of 24 continues to be executed. During this circulation process, in steps 204 and 206, as in the first embodiment, the front wheel steering angle Of is input as the driver's operation signal.
is read, and the vehicle speed V is read as a vehicle status signal.
After reading, in step 208, the front wheel steering angle o
Based on f and vehicle speed V, load movement amount Δ due to vehicle turning
M is calculated. This load movement amount ΔM is the amount of load that moves from the inside front and rear wheels to the outside front and rear wheels when the vehicle turns.In step 208, first, the front wheel steering angle o
The centrifugal force acting on the vehicle body BD is estimated based on f and the vehicle speed V, and the load movement amount ΔM is estimated based on the estimated calculation result. After the processing in step 208, as in the case of the first embodiment, in steps 210 and 212, the front wheel steering angle of, the pressure HGP of gripping the steering wheel WH, and the driver's heart rate BPN are obtained as the driver's status signals. At the same time, the driver's condition is determined according to the read data and a driver condition flag DSF is set. Now, the driver is in a normal state and the driver state flag DSF
is “O”, rYESJ in step 214
Based on the determination, the table in the ROM 25b is referred to in step 216, and the front-rear load distribution ratio K t r is set to the value K.
+rl1. When bending, front and rear load distribution ratio K
As shown by the solid line in FIG. 7, rrs takes a value closer to the rear wheels at low vehicle speeds, and changes to a value closer to the front wheels as the vehicle speed V increases. In addition, some explanation will be added here regarding the front-rear load distribution ratio near the rear wheel or front wheel. For example, if a load of "10" is transferred from the inside wheel to the outside wheel when the vehicle turns, of this "1o" load, the rear 11IRWI, RW2 will bear the load of "6",
And when the front wheels FWI and FW2 bear the load of "4", the front and rear load distribution ratio is said to be closer to the rear wheels, and in this case, the average cornering power of the rear wheels RWI and RWI is equal to
It becomes smaller than the average cornering power of I, FW,
1 more left! rRW1 and RW2 become more slippery than front wheels FW1 and FW2, and the vehicle tends to oversteer. In addition, when the load of "6" is borne by the front 11tFWl, FW2 out of the load movement amount "10", and the load of "4J is borne by the rear wing RWI, RW2", the front and rear load distribution ratio is closer to the front wheels. In such a case, the previous alIFW1,F
The average cornering power of W is rear wheel RWI, RW1
The average cornering power of the front wheel F.
W1 and FW2 become more slippery than rear wheels RWI and RW2, and the vehicle tends to understeer. After the processing in step 216, in step 218, each target oil pressure {[I P + ~ P4 is calculated, and in step 218 each calculated target oil pressure {lIP1~P
Each control signal representing 4 is outputted to the lipid circuit 37 via the input/output port 25g. As a result, the waste circuit 37 responds to the output control signals to increase or decrease the pressure. 11#
Controls valves 31a to 34a. As a result, each oil pressure value in the hydraulic cylinders 31 to 34 is changed to each target oil pressure value P1 to
P4, and each of the cylinders 31 to 34 supports the vehicle body BD by sharing the load corresponding to each of the target oil pressure values PI-Pa. As a result, when the vehicle is turning, the outer front and rear wheels bear the load movement amount ΔM according to the front and rear load distribution ratio K t r , and when the vehicle is running at low speed, the front and rear load distribution ratio K t r is closer to the rear wheels. Therefore, the vehicle tends to oversteer, improving its turning performance. In addition, when the vehicle is running at high speed, the front and rear load distribution ratio K
r r is closer to the front wheels, and the vehicle tends to understeer, improving driving stability. On the other hand, as a result of the determination process in step 212, if the driver's condition is abnormal and the driver status flag DSF is set to "1", based on the determination of "N○" in step 214, step At step 222, similarly to the first embodiment, the sound of the buzzer 29 is controlled to call the driver's attention. Then, in step 224, the table in the ROM 25b is referred to, and the front-rear load distribution ratio K t r is set to the value K t
r+. In such a case, the front and rear load distribution ratio K
As shown by the broken line in FIG. 7, t r + is a value larger on the positive side than {[[K+,9], that is, a value closer to the front wheels, which is set when the driver is normal. As a result, when the driver is in an abnormal state, as a result of the processing in steps 218 and 220, the vehicle is set to have a tendency to understeer more than normal. It will be done. This means that when the driver falls into an abnormal state, the vehicle is controlled so that the amount of change in the vehicle's attitude in response to the steering wheel operation is reduced. Also in the second embodiment, the vehicle is The vehicle is controlled to drive safely in response to abnormal conditions of the driver, and the vehicle turns responsiveness to steering wheel operations is slowed down, making it easier to drive the vehicle even when the driver is fatigued. C. Third Embodiment An example in which the present invention is applied to a vehicle equipped with a power steering system PS capable of changing the steering assist force will be described with reference to the drawings. FIG. 8 schematically shows this power steering device PS, which is composed of a control valve 41, a vane pump 42, a flow divider valve 43, an electromagnetic valve 44, a reservoir 45, etc. In conjunction, supply and discharge of hydraulic oil to and from the power cylinder 46 are controlled to assist the rotational operation. In addition, in this power steering system PS, by controlling the hydraulic pressure in the hydraulic reaction force chamber 41a provided in the control valve 41 according to the opening degree of the electromagnetic valve 44, the reaction force against the driver's steering operation is changed. It's about to be controlled. In such a case, the electromagnetic valve 44 is configured to increase the valve opening as the current to the solenoid 44a built in the valve 44 increases, and the hydraulic reaction force chamber increases as the valve opening increases. The hydraulic pressure inside 41a is reduced, and the steering reaction force is reduced. In the third embodiment, the motion characteristic changing device of the present invention capable of changing the amount of change in attitude of the vehicle in response to steering wheel operation corresponds to the hydraulic reaction force chamber 41a and the electromagnetic valve 44. This power steering system PS includes a front wheel steering angle sensor 19, a vehicle speed sensor 22, a steering wheel pressure sensor 23, and a receiver similar to those in the first embodiment, in order to control the amount of electricity supplied to the solenoid 44a in the electromagnetic valve 44. r! 24,
It includes a microcomputer 25, a transmitter 26, a heart rate sensor 27, and a buzzer 29. However, in this microcomputer 25, the ROM 25b stores programs corresponding to the flowcharts of FIGS. 4 and 9, and also stores the valve opening degree VLV with respect to the vehicle speed V as shown in FIG. 10 in the form of a table. I remember. Further, an excitation circuit 47 for controlling excitation of the solenoid 44a is connected to the output port 25f. Next, the operation of the third embodiment configured as described above will be explained with reference to the flow chart of FIG. In this embodiment as well, when the ignition switch is closed, execution of the program is started in step 300, and after initialization in step 302, steps 304 to 3 are started.
A circular process consisting of 18 continues to be executed. During this circulation process, in step 304, the vehicle speed V is read as a vehicle status signal, as in the case of each of the above embodiments, and then in step 306, RO is determined based on the read vehicle speed V.
The table in M25b is referred to, and as shown by the solid line in FIG. 10, the valve opening degree V that changes depending on the vehicle speed
LV is derived. After processing in step 306, in steps 308 and 310, the front wheel steering angle θf, the pressure on the steering wheel WH gripping the steering wheel WH, and the driver's heart rate BPN are determined in steps 308 and 310, as in the case of each of the embodiments described above. At the same time, the driver's condition is determined according to the read data and a driver condition flag DSF is set. Now, the driver is in a normal state and the driver state flag DSF
is "O'", rYES in step 312
Based on the determination of J, in step 318, a control signal representing the derived valve opening degree VLV is outputted to the excitation circuit 47 via the output boat 25f. The excitation circuit 47 controls the output of the solenoid 44a based on the supply control signal. The opening degree of the electromagnetic valve 44 is adjusted to the derived valve opening degree VL by controlling the amount.
Control so that it becomes V. In this case, the derived valve opening VLV is designed to decrease as the vehicle speed increases, as shown by the solid line in FIG. 10, so the oil pressure in the hydraulic reaction chamber 41a increases as the vehicle speed V increases. However, according to the power steering device PS, a light steering operation is realized when the vehicle is running at low speed, and a responsive steering operation is realized when the vehicle is running at high speed, resulting in a good steering feeling. On the other hand, as a result of the determination process in step 310, if the driver is abnormal and the driver status flag DSF is set to "work", the process proceeds to step 314 based on the determination of "N○" in step 312. As in each of the above embodiments,
The sound of the buzzer 29 is controlled to call the attention of the person returning. Then, in step 316, the step 30
A predetermined value Δ is calculated from the valve distance VLV derived by the process in step 6.
V is calculated by M, the corrected valve opening degree VLV-Δ■ is determined, and in step 318 the electromagnetic valve 4 is
The valve opening degree of No. 4 is controlled to be set to this corrected valve opening degree VLV - ΔV (see the broken line in FIG. 10). As a result, in such a case, the valve opening degree of the IT magnetic valve 44 is lowered by ΔV than in the above case, and the hydraulic pressure in the hydraulic reaction force chamber 41a is increased, so that when the driver is in an abnormal state, , the operation of the steering wheel WH becomes heavier than normal. This means that when the driver falls into an abnormal state, the steering assistance force of the front wheels FWI, FW2 in response to the steering wheel operation is reduced, that is, the vehicle is controlled to the side where the amount of change in attitude of the vehicle in response to the steering wheel operation is reduced. This means that in the third embodiment as well, the vehicle is directed to deal with the driver's abnormal condition and drive safely! Il
l# will be done. d. Fourth Embodiment An example in which the present invention is applied to a vehicle equipped with a steering device capable of changing the steering ratio (handle steering amount/front wheel turning angle) will be described with reference to the drawings. FIG. 11 schematically shows this steering device, and the steering device includes a housing 51 formed in a cylindrical shape and supported on a vehicle body (not shown) so as to be displaceable in the axial direction. A rack par 52 is supported in the housing 51 so as to be displaceable in the axial direction, and the bar 52 includes a pinion 53 that meshes with the bar 52, and an intermediate shaft 54a (which allows slight bending of the steering shaft 54). It is connected to the steering handle WH via a steering shaft 54 including a steering shaft 54, and is connected to the left and right front wheels FWI at both ends thereof via left and right tie rods 55a, 55b and left and right knuckle arms 56'a, 56b. FW2 is connected so that it can be steered. A power cylinder 57 for driving the rack par 52 is integrally formed inside the housing 5.
The discharge of hydraulic oil to the steering wheel 7 is controlled by a control valve 58 provided in the housing 51 in accordance with the steering torque acting on the steering shaft 54. A hydraulic pump 59 and a reservoir 60 are connected to this control valve 58 . Further, a bracket 61 is integrally fixed to the housing 51, and the bracket 61 is connected to a piston rod 62a of a hydraulic cylinder 62 so that it can be displaced and rotated with respect to the vehicle body by the cylinder 62. There is. A servo valve 63 is connected to the hydraulic cylinder 62 , and the valve 63 is controlled by a servo amplifier 64 to supply oil discharged from the hydraulic pump 59 to one oil chamber of the hydraulic cylinder 62 . The hydraulic oil in the other oil chamber is discharged to the reservoir 60. The housing 5 is connected to the positive input (+) of the servo amplifier 64.
A corrected steering amount Δθ representing an axial displacement amount of 1 is supplied,
A displacement sensor 65 that detects the displacement of the piston rod 62a is connected to the negative input (1) of the amplifier 64, and the amplifier 64 switches the servo valve 63! 1 to feedback control the amount of movement of the housing 21 by the corrected steering amount Δθ. In the fourth embodiment, the steering angles of the left and right front wheels FWI, FW2 are controlled by the axial displacement of the rack par 52 and the axial displacement of the housing 51, and the posture of the vehicle with respect to steering wheel operation is controlled. The motion characteristic changing device of the present invention capable of changing the amount of change corresponds to the housing 5l, the hydraulic cylinder 62, the servo valve 63, and the like. In addition, in order to form and output the corrected steering amount Δθ, this vehicle also includes a front wheel steering angle sensor l9, a steering wheel pressure sensor 23, a steering wheel pressure sensor 23, and a receiver It. vessel 2 4,
It is equipped with a microcomputer 25, a transmitter 26, a heart rate sensor 27, and a buzzer 29. However, in this microcomputer 25, the ROM 25b stores programs corresponding to the flowcharts of FIGS. 4 and 12. Further, the input/output boat 25g is connected to the positive input (+) of the servo amplifier 64. Next, the operation of the fourth embodiment configured as described above will be explained in the 12th embodiment.
This will be explained with reference to the flowchart shown in the figure. In this embodiment as well, when the ignition switch is closed, execution of the program is started in step 400, and after initialization in step 402, steps 404 to 4 are started.
A circular process consisting of 18 continues to be executed. During this circulation process, as in each of the above embodiments, the front wheel steering angle of is read as the driver's operation signal in step 404, and then the front wheel steering angle of is read as the driver's status signal in steps 408 and 408. Angle θf, pressure H to grip the steering wheel WH
The GP and the driver's heart rate BPN are read, and the driver's condition is determined according to the read data, and a driver condition flag DSF is set. Now, the driver is in a normal state and the driver state flag DSF
is “O”, rYESJ in step 410
Based on the determination, the corrected steering amount Δθ is set to rOJ in step 412, and in step 414, the corrected steering amount Δθ representing the rOJ is input to the positive side input (+) of the servo amplifier 64 via the input/output port 25g. ). The servo amplifier 64 is connected to the displacement sensor 65! supply and discharge of hydraulic oil to and from a hydraulic cylinder 62 via a servo valve 63 is controlled by m, and the cylinder 62 maintains the housing 5 in a neutral position. In this state, the driver turns the steering wheel W.
When H is rotated, the rotation is transmitted to the rack bar 52 via the steering shaft 54 and pinion 53, and the bar 52
is displaced in the axial direction by an amount corresponding to the amount of rotation of the steering handle WH while being assisted by the power cylinder 57, and the left and right front wheels FWI, FW2 are steered left and right by the amount of displacement of the rack par 52. On the other hand, as a result of the determination process in step 408, if the driver is abnormal and the driver status flag DSF is set to "1", the process proceeds to step 416 based on the determination of "N○" in step 410. As in each of the above embodiments,
The sound of the buzzer 29 is controlled to call the driver's attention. Then, in step 418, the corrected steering amount ΔO is set to the value 1k·o obtained by multiplying the front wheel steering angle of by a negative constant “1k”.
f, and in step 414, the value -k·θf is supplied to the net input (+) of the servo amplifier 64 as the corrected steering amount Δθ. As a result, the hydraulic cylinder 62 is controlled by the servo amplifier 64, displacement sensor 65, and servo valve 63, and the cylinder 62 moves the housing 5l in the axial direction by an amount corresponding to the corrected steering amount Δθ (=-k・Of). Displace. The direction of displacement of the housing 5l is opposite to the direction in which the rack par 52 is displaced by rotation of the steering handle WH,
The amount of displacement of the rack par 52 in the axial direction with respect to the vehicle body is reduced by the corrected steering amount Δθ. As a result, when the driver is in an abnormal condition, the left and right front wheels FWI and FW2 are adjusted according to the rotation angle of the steering wheel WH.
The steering angle (steering ratio) becomes smaller than normal. This means that when the driver falls into an abnormal state, the turning characteristics of the vehicle in response to the steering wheel operation are controlled to tend toward understeer, that is, the vehicle is controlled to the side where the amount of change in the vehicle's attitude in response to the steering wheel operation is reduced. This means that in the fourth embodiment as well, the vehicle is controlled in a direction in which the turning response to steering wheel operations becomes slower in response to the driver's abnormal condition, that is, in a direction in which it runs safely. Become. e. Fifth Embodiment An example in which the present invention is applied to a four-wheel steering vehicle in which the steering angle ratio (rear wheel steering angle/front wheel steering angle) can be changed will be described with reference to the drawings. FIG. 13 schematically shows this four-wheel steering vehicle, in which front wheel steering is transmitted from the front wheel steering device to the rear wheel steering device via a rotating shaft 71. . The front wheel steering device includes a rack bar 74 connected to the steering handle WH via a pinion 72 and a steering shaft 73, and left and right tie rods 75a, 75 are attached to both ends of the bar 74.
b and left and right knuckle arms 7 6 a, 7 6 b
The left and right front wheels FW↓ and FW2 are connected to each other so that they can be steered. Also, this rack par 74 has a rotating shaft 7.
A pinion 77 provided at the front end of the shaft is engaged. The rear wheel steering device adjusts the left and right rear wheels RWl, R by axial displacement.
Equipped with relay rod 78 to steer W2, the same Rondo 78
is connected to the left and right rear wheels RWI at both ends via left and right tie rods 79a, 79b and left and right knuckle arms 80a, 80b.
, RW2 are connected in a steerable manner. Eight steering angle ratio setting mechanisms are interposed between the relay rod 78 and the rear end of the rotary shaft 71. The steering angle ratio setting mechanism 8l controls the rotation of the rotary shaft 71 by relay iron 78.
By converting the displacement in the axial direction to the left and right rear wheels RWI,
The RW2 is steered in conjunction with the left and right front wheels FWl, FW2, and the steering angle ratio is set and controlled by variably controlling the displacement direction and displacement amount of the relay rod 78 with respect to the rotation of the rotary shaft 71. 1986-16
A known method disclosed in Japanese Patent No. 3064 can be used. Further, an electric motor 82 is assembled in the steering angle ratio setting mechanism 81, and the motor 82 changes the steering angle by driving a steering angle ratio changing member (not shown) in the mechanism 8. The ratio is controlled to change from a predetermined anti-phase value to a predetermined in-phase value. In this fifth embodiment, the steering angle ratio setting mechanism 81 and the electric motor 82
corresponds to the motion characteristic changing device of the present invention that can change the amount of change in the attitude of the vehicle. A servo amplifier 83 is connected to this electric motor 82. The servo amplifier 83 performs feedback control of the rotational position of the electric motor 82, and its positive side input (+) is supplied with a control signal representing the steering angle ratio K, and its negative side input (1) is supplied with a control signal representing the steering angle ratio K. A rotational position sensor 84 for detecting the rotational position of 82 is connected. In addition, in order to set and control the steering angle ratio, this front and rear wheel steered vehicle also includes a front wheel steering angle sensor 9 similar to that in each of the embodiments described above;
Vehicle speed sensor 22, steering wheel pressure sensor 23, receiver 24
, a microcomputer 25, a transmitter 26, a heart rate sensor 27, and a buzzer 29. However, in this microcomputer 25, the ROM 25b stores programs corresponding to the flowcharts in FIGS. The ratio K is memorized in the form of a table. Further, the positive side input (+) of the servo amplifier 83 is connected to the input/output boat 25g. Next, the operation of the fifth embodiment configured as described above will be explained in the 14th embodiment.
This will be explained with reference to the flowchart shown in the figure. In this embodiment as well, when the ignition switch is closed, execution of the program is started in step 500, and after initialization in step 502, steps 504 to 5 are started.
A circular process consisting of 18 continues to be executed. During this circulation process, in step 504, the vehicle speed ■ is read as the vehicle status signal, as in the case of each of the above embodiments, and then in step 506, the RO is determined based on the read vehicle speed V.
The table in M25b is referred to, and the steering angle ratio K, which changes depending on the vehicle speed V, is derived as shown by the solid line in FIG. After the processing in step 506, in steps 508 and 510, as the driver's status signals, the front wheel steering angle Of, the pressure HGP in gripping the steering wheel WH, and the driver's heart rate BPN are determined as in each of the above embodiments. At the same time, the driver's condition is determined according to the read data and a driver condition flag DSF is set. Now, the driver is in a normal state and the driver state flag DSF
is “O”, rYEsJ in step 512
Based on the determination, in step 518, the derived steering angle ratio K
A control signal representing this is output to the servo amplifier 83 via the input/output port 25g. The servo amplifier 83 cooperates with the rotational position sensor 84 to control the rotational position of the electric motor 82 to a position corresponding to the steering angle ratio K. As a result, the steering angle ratio setting member in the steering angle setting mechanism 8l is controlled by the electric motor 82, and the mechanism 81 sets and controls the set steering angle ratio to the derived steering angle ratio K. When the steering handle WH is rotated in this state, the rotation is transmitted to the rack par 7 via the steering shaft 73 and the pinion 72.
4, the bar 74 is displaced in the axial direction by an amount corresponding to the rotation angle of the steering handle WH, and the left and right front wheels FWI
, FW2 are steered left and right in response to the rotation of the steering handle WH. On the other hand, the rotation shaft 71 rotates due to the axial displacement of the rack par 74, and the rotation is transmitted to the steering angle ratio setting mechanism 81. As a result, left and right rear 1! IRW1
, RW2 are steered in conjunction with the steering of the left and right front wheels FWI, FW2, but the left and right rear wheels 11rRW1, RW2 are steered in conjunction with the steering of the left and right front wheels FWI, FW2.
The steering angle ratio for WI and FW2 changes according to the characteristics shown by the solid line in FIG. In other words, when the vehicle is running at low speed, the steering angle ratio is set in the opposite phase, improving the vehicle's tight turning performance. Furthermore, when the vehicle is running at high speed, the steering angle ratios are set to be in phase, and the steering angle ratios are set to be in phase. The line stability is improved. Further, as a result of the determination process in step 510, if the driver is abnormal and the driver status flag DSF is set to "■", the process proceeds to step 514 based on the determination of "N○" in step 512. As in each of the above embodiments,
The sound of the buzzer 29 is controlled to call the driver's attention. Then, in step 516, the step 50
A predetermined value ΔK is added to the steering angle ratio K derived in step 6 to determine a corrected steering angle ratio K+ΔK, and in step 518, the set steering angle ratio in the steering angle ratio setting mechanism 81 is adjusted as described above. The steering angle ratio is set to K+ΔK (first
(See dashed line in Figure 5). As a result, in such a case, the steering angle ratio K is set to a value larger on the ΔK partial pressure side, that is, on the in-phase side, than in the above case, so that when the driver is in an abnormal state,
Compared to normal conditions, the left and right rear wheels RW1 and RW2 are now the left and right front wheels FW.
The tendency to be steered toward the same phase side with respect to I and FW2 increases, and driving stability becomes better. In other words, this means that when the driver falls into an abnormal state, the turning characteristics of the vehicle in response to the steering wheel operation are controlled to tend toward understeer, that is, the vehicle is controlled to the side where the amount of change in the vehicle's attitude in response to the steering wheel operation is reduced. Also in the fifth embodiment, the vehicle is controlled in a direction in which the turning response to steering wheel operations becomes slower in response to the driver's abnormal condition, that is, in a direction in which the vehicle runs safely. It turns out. f. Other Modifications In each of the above embodiments, when the driver falls into an abnormal state such as falling asleep, the buzzer 29 is sounded to call the driver's attention. Showa 6
As shown in Japanese Patent Publication No. 0-135331 and Japanese Patent Publication No. 59-16968, etc., the seat is vibrated, the blower is activated to blow cold air to the driver, and the radio and cassette tape device are activated. The driver may be alerted by playing music or automatically opening the windows. Furthermore, in each of the embodiments described above, the driver's condition is classified into two types, normal and abnormal, and the dynamic characteristics of the vehicle in response to the driver's operation are switched and controlled between the two types according to the determination. The condition of the driver, especially fatigue,
The motion characteristics of each of the above embodiments may be continuously controlled depending on the degree of fatigue (size of handle grip force).

[Brief explanation of drawings]

FIG. 1 is a perspective view schematically showing a vehicle according to a first embodiment of the present invention, FIG. 2 is a control circuit diagram for controlling the suspension system shown in FIG. 2 is a flowchart of a program executed by the microcomputer, FIG. 5 is an overall schematic diagram of a vehicle suspension system according to a second embodiment of the present invention, and FIG. 7 is a characteristic diagram of the front-rear load distribution ratio when the vehicle turns in the suspension system of FIG. 5, and FIG. 8 is an overall schematic diagram of a power steering system for a vehicle according to a third embodiment of the present invention. , FIG. 9 is a flowchart of a program executed by the microcomputer shown in FIG. 8, FIG. 10 is a characteristic diagram of the steering reaction force in the power steering device shown in FIG. 8, and the first drawing is a fourth embodiment of the present invention. FIG. 12 is a flowchart of a program executed by the microcomputer shown in FIG. 1l, and FIG. 13 is an overall schematic diagram of a front wheel steering device of a vehicle according to a fifth embodiment of the present invention. 14 is a flowchart of a program executed by the microcomputer shown in FIG. 13, and FIG. 15 is a characteristic diagram of the steering angle ratio in the four-wheel steered vehicle shown in FIG. 13. Explanation of symbols BD...Vehicle body, WH...Steering handle, FW1,F
W2...Front wheel, RWI, RW2... Rear wheel, PS...
・Power steering device, 11 to 14・・Shock absorber, lla to 14a・Electromagnetic actuator,
15-18...Coil spring, . 19... Front wheel steering angle sensor, 2o... Throttle opening sensor, 2
l... Brake switch, 22... Vehicle speed sensor, 2
3. Handle pressure sensor, 24. Receiver, 25.
・Microcomputer, 26...Transmitter, 27・
...Heart rate sensor, 29...Buzzer 31-34...
Hydraulic cylinder, 31a to 34a...pressure control valve,
41. Control valve, 41a... Hydraulic counter chamber, 42... Hydraulic pump, 44... Solenoid valve, 4
4a・Solenoid, 46...Power cylinder, 51・
...Housing, 52...Rack par 62...Hydraulic cylinder, 63...Servo valve, 64...Servo amplifier, 71...Rotating shaft, 74...Rack bar, 78...Relay rod, 81... - Steering angle ratio setting mechanism, 82. - Electric motor, 83... Servo amplifier.

Claims (1)

[Claims] a motion characteristic changing device capable of changing vehicle motion characteristics based on a driver's operation; a driver condition detection means for detecting a driver condition; and a driver condition detection means according to the driver condition detected by the driver condition detection means. and a change control means for controlling the dynamic characteristic changing device to change the dynamic characteristic of the vehicle based on the driver's operation according to the condition of the driver. .