JP6573219B2 - Brake control device for vehicle - Google Patents

Description

  The present invention relates to a vehicle brake control device, and more particularly to a vehicle brake control device capable of controlling the behavior of a vehicle based on a brake characteristic adapted to human perceptual characteristics.

Conventionally, in vehicle control, when an occupant operates a brake pedal, a target operation amount is set based on an operation characteristic (control map) that defines the correlation between the operation amount of the brake pedal and the deceleration of the vehicle, The behavior behavior of the vehicle is controlled.
On the other hand, in order to improve the occupant's operational feeling, many control devices have been proposed that perform vehicle control in accordance with the occupant's sensitivity based on psychophysics.
Weber-Fechner's law and Stevens' law are known as expressions of the relationship between physical quantities and sensory quantities (perceptual quantities).
Fechner's law is the law that the sensory quantity is proportional to the logarithm of the stimulus intensity, and Stevens' law is the law that the sensory quantity is proportional to the power of the stimulus intensity.

  The vehicle control device of Patent Document 1 includes an acceleration generation device that generates acceleration in a vehicle, and a control device that controls the acceleration generation device based on an accelerator opening and a vehicle speed according to an accelerator pedal operation by an occupant, The relationship between the accelerator opening and the required acceleration is changed while maintaining the characteristic by the Weber-Fechner exponent function based on the minimum generated acceleration that can be generated by the acceleration generator.

In recent years, an operating means operated by an occupant, a reaction force generating mechanism that applies an operating reaction force to the operating means, and a driving means that drives a vehicle to operate a predetermined response amount according to an operation amount with respect to the operating means, There is known a by-wire vehicle equipped with
In a vehicle adopting such a by-wire system, the operation means and the drive means are replaced with a connection by an electrical signal instead of a connection by a mechanical mechanism, so that the actual operation amount of the operation means by the occupant, the reaction force amount to the occupant, and the vehicle Each is configured as an independent element in which the response amount is mechanically separated.

The brake device of Patent Document 2 includes an operation amount detection unit that detects an operation amount of a brake pedal, an electric actuator that generates a reaction force of the brake pedal based on the operation amount of the brake pedal, and a motor cylinder that generates a braking force on wheels. And a control means capable of controlling the electric actuator and the motor cylinder, and the hysteresis set between the stepping characteristic and the stepping-back characteristic at the time of the heel and toe operation is made larger than the hysteresis at the time of the normal operation.
Moreover, the brake device of patent document 3 has changed the hysteresis according to the operation amount of the brake pedal, the operation speed, or the vehicle speed.

JP 2011-143915 A JP 2008-2222030 A JP-A-2015-000582

In general, in driving a vehicle, the driving state changes in the order of environmental recognition by the occupant, situation determination by the occupant, device operation by the occupant, and response operation by the vehicle. Here, recognition, determination, and operation are elements that are mainly determined in the sensation area of the occupant, and a response amount associated with the behavior of the vehicle is an element that is mainly determined in the physical area.
Therefore, there is a discrepancy between the amount of perception that the occupant feels through visual or somatic sensation and the physical response amount that the vehicle actually operates, and the amount of perception that the occupant feels through somatic sensation. There is also a divergence from the physical operation amount (or reaction force amount accompanying the operation) for actually operating the operation means.
In other words, in a situation where the occupant is operating the vehicle operating means, it is necessary to appropriately give the occupant a perception amount that takes into account the sensation characteristics of the occupant, based on the perception characteristics of the human limbs.

The brake pedal depression and retraction operation by the occupant is a movement of flexion and extension of the lower limb joint, and is affected by the characteristics of the skeletal system in order to change the direction of the force in the opposite direction. From the viewpoint of muscle activity, it is mainly regarded as the coordinated activity of the lower limb muscles involving the soleus and gastrocnemius muscles for pushing the foot corresponding to the plantar and dorsiflexion movements of the ankle joint, and the anterior tibial muscle for lifting. Can be tricked.
Skeletal muscles are classified into active muscles that cause joint movement by muscle contraction due to motor action, and antagonistic muscles that work oppositely when paired with active muscles. During the stepping operation, the main muscles are the soleus and gastrocnemius muscles, and the antagonistic muscles are the anterior tibial muscles. The operation mainly using the anterior tibial muscle is performed.
In other words, in the braking characteristic consisting of the pedaling force and deceleration, the hysteresis that intervenes between the depression characteristic and the retraction characteristic is changed to the function of the antagonistic muscle (active muscle). By setting so as to correspond to the period required for switching, the so-called function switching period, a braking characteristic that is sensibly excellent in response to the occupant, in other words, a braking characteristic that matches the muscular characteristic of the occupant. Can be obtained.

The brake devices of Patent Documents 2 and 3 are set such that the smaller the pedal force (stroke), the smaller the hysteresis. In other words, when viewed from the side of the muscle characteristics, the hysteresis is set so that the hysteresis becomes smaller as the muscle momentum is lower and the function switching period is shorter, so that it is considered that the sensory responsiveness of the vehicle behavior can be secured.
However, in the brake devices of Patent Documents 2 and 3, when the occupant shifts from the stepping operation to the stepping back operation, there is a possibility that the vehicle behavior with respect to the operation by the occupant may feel uncomfortable.
In other words, since the rate of change in the stepping characteristic is significantly larger than the rate of change in the stepping characteristic, even if the occupant changes the pedaling force to the same extent, the deceleration change tendency due to the stepping operation and the decrease due to the stepping operation are reduced. Unlike the speed change tendency, a sense of discomfort is generated in the passenger. In particular, in the region near zero deceleration, the hysteresis becomes extremely small, and there is a possibility that the vehicle behavior becomes unstable due to a slight change in the pedaling force.

  An object of the present invention is to provide a vehicle brake control device and the like that can ensure the responsiveness of the vehicle without causing the passenger to feel uncomfortable operation.

According to a first aspect of the present invention, there is provided a vehicle brake control device comprising: an operation amount detection unit that detects an operation amount of a brake pedal; a reaction force generation mechanism that generates a reaction force of the brake pedal based on the operation amount of the brake pedal; A vehicle braking control device comprising: a braking force generating mechanism that generates a braking force; and the reaction force generating mechanism and a control unit capable of controlling the braking force generating mechanism. Braking characteristic setting means for setting a braking characteristic comprising a stepping characteristic and a stepping return characteristic offset by a hysteresis to the stepping force decreasing side from the stepping characteristic. the residual depression force when the deceleration zero at the releasing characteristic is set and below 10N or more 2N, said control means, said braking characteristic the lower the deceleration the releasing start hysteresis It is characterized by controlling the braking force generating mechanism on the basis of the braking characteristics as well as reduce the cis.

In this vehicle braking control device, the braking characteristic is set by the depression force according to the reaction force of the brake pedal and the deceleration of the vehicle, and the depression characteristic and the depression characteristic are offset by a hysteresis to the depression force reducing side. The braking characteristic setting means for setting the braking characteristic consisting of the stepping-back characteristic can make the change tendency of the stepping characteristic and the changing tendency of the stepping characteristic almost the same. It is possible to avoid a sense of incongruity when moving to.
The control means reduces the hysteresis of the braking characteristic as the deceleration at the start of stepping back decreases and controls the braking force generation mechanism based on the braking characteristic. Therefore, the function switching period between the active muscle and the antagonistic muscle is large. Can be increased, and when the function switching period between the main and antagonist muscles is reduced, the hysteresis can be reduced. As a result, the responsiveness of vehicle behavior can be reduced. Can be adapted to the properties.
In addition, since the remaining pedal force when the deceleration is zero in the stepping-back characteristic is set to 2N or more and 10N or less, the operability of the brake pedal in the region near zero deceleration can be ensured. This is because when the remaining pedal force is less than 2N, it is difficult to perceive with the tactile sensation and muscles of the sole, and when the remaining pedal force exceeds 10N, the end of stepping back (zero deceleration) cannot be recognized by the sense of leg.

According to a second aspect of the present invention, there is provided an operation amount detecting means for detecting an operation amount of the brake pedal, a reaction force generating mechanism for generating a reaction force of the brake pedal based on the operation amount of the brake pedal, and a braking force for the wheel. In the vehicle braking control device, comprising: a braking force generation mechanism for controlling the reaction force generation mechanism; and a control unit capable of controlling the braking force generation mechanism; a pedaling force corresponding to the reaction force of the brake pedal; A braking characteristic setting means for setting a braking characteristic that includes a stepping characteristic and a stepping characteristic that is offset from the stepping characteristic by a hysteresis toward the stepping force reduction side . the set under the following depression start pedaling force when the deceleration zero in the remaining pedal force and not more than the pedaling characteristic when deceleration zero at the releasing characteristic, said control means, the releasing opening It is characterized by deceleration of controlling the braking force generating mechanism on the basis of the braking characteristics with reduced hysteresis of the braking characteristic as low.
According to this configuration, when the occupant shifts from the stepping operation to the stepping back operation, it is possible to avoid a sense of incongruity and to adapt the responsiveness of the vehicle behavior to the muscle characteristics of the occupant. In addition, it is possible to ensure the operability of the brake pedal in the region near zero deceleration while ensuring the function switching period between the main muscle and the antagonist muscle.

According to a third aspect of the present invention, there is provided an operation amount detecting means for detecting an operation amount of the brake pedal, a reaction force generating mechanism for generating a reaction force of the brake pedal based on the operation amount of the brake pedal, and a braking force for the wheel. In the vehicle braking control device, comprising: a braking force generation mechanism for controlling the reaction force generation mechanism; and a control unit capable of controlling the braking force generation mechanism; a pedaling force corresponding to the reaction force of the brake pedal; Braking characteristic setting means for setting a braking characteristic which is a braking characteristic set by the stepping characteristic and a stepping return characteristic offset from the stepping characteristic by a hysteresis toward the stepping force reduction side. , the deceleration and the pedal force is set to be a logarithmic relationship, said control means, the control as to reduce the hysteresis of the braking characteristic the lower the deceleration the releasing initiation It is characterized by controlling the braking force generating mechanism on the basis of the characteristics.
According to this configuration, when the occupant shifts from the stepping operation to the stepping back operation, it is possible to avoid a sense of incongruity and to adapt the responsiveness of the vehicle behavior to the muscle characteristics of the occupant. In addition, it is possible to make the occupant perceive a deceleration proportional to the pedal effort, and to improve the operability of the brake pedal.

  According to the vehicle brake control device of the present invention, by adapting the braking characteristics of the vehicle to the muscle characteristics of the occupant, the responsiveness of the vehicle can be ensured without causing the occupant to feel uncomfortable operation.

1 is a schematic configuration diagram of a vehicle brake control device according to a first embodiment. It is a map of the pedaling force characteristic which shows the relationship between a stroke and pedaling force. It is a map of the braking characteristic which shows the relationship between pedal effort and deceleration. It is a map of the braking rigidity characteristic which shows the relationship between deceleration and braking rigidity. It is a time chart about each element at the time of vehicle braking.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The following description is an example in which the present invention is applied to a vehicle brake control device, and does not limit the present invention, its application, or its use.

Embodiment 1 of the present invention will be described below with reference to FIGS.
As shown in FIG. 1, the braking control device 1 includes a master cylinder 3 that forms a brake-by-wire mechanism and can generate brake fluid pressure according to the stroke (depressed state) of the brake pedal 2, and the front, rear, left, and right wheels FL of the vehicle. , FR, RL, and RR are provided with a brake fluid pressure generating mechanism 5 (braking force generating mechanism) that can supply brake fluid pressure to the wheel cylinders 4a to 4d that brake the rotation of the wheel cylinders 4a to 4d, respectively.
When the brake fluid pressure generating mechanism 5 is normal, the brake fluid pressure generating mechanism 5 supplies a brake fluid pressure that is boosted (for example, twice or more) to the operation of the brake pedal 2 to the wheel cylinders 4a to 4d. When the brake fluid pressure generating mechanism 5 is abnormal, the master cylinder 3 supplies the brake fluid pressure corresponding to the operation of the brake pedal 2 to the wheel cylinders 4a to 4d.
Furthermore, a reaction force generation mechanism 6 is provided that causes the brake pedal 2 to generate a reaction force corresponding to the stroke of the brake pedal 2 when the brake fluid pressure generation mechanism 5 is normal.

First, the master cylinder 3 will be described.
The master cylinder 3 includes a first pressure generation chamber 3a and a second pressure generation chamber 3b.
The first and second pressure generating chambers 3a and 3b are respectively connected to the reservoir tank 7 and have compression springs therein. These first and second pressure generating chambers 3 a and 3 b are configured to be able to pump substantially the same brake fluid pressure in accordance with the depression operation of the brake pedal 2.
The first pressure generating chamber 3a communicates with the wheel cylinders 4a and 4b via the electromagnetic valve 11 that can be opened and closed, and the second pressure generating chamber 3b communicates with the wheel cylinders 4c and 4d via the electromagnetic valve 14 that can be opened and closed. Has been. The solenoid valves 11 and 14 are closed when being energized, and are opened while being deenergized when the brake fluid pressure generating mechanism 5 is abnormal.

Next, the brake fluid pressure generating mechanism 5 will be described.
The brake fluid pressure generating mechanism 5 is connected to the reservoir tank 7 and is constituted by an electric motor, a hydraulic pump, and the like.
The brake fluid pressure generating mechanism 5 is communicated with the wheel cylinders 4a and 4b via an electromagnetic valve 12 that can be opened and closed, and is communicated with the wheel cylinders 4c and 4d via an electromagnetic valve 13 that can be opened and closed. The solenoid valves 12 and 13 are opened when energized.

As shown in FIG. 1, when the solenoid valves 11 and 14 are opened and the solenoid valves 12 and 13 are closed, the brake fluid pressure is directly supplied from the master cylinder 3 to the wheel cylinders 4a to 4d. When the solenoid valves 11 and 14 are closed and the solenoid valves 12 and 13 are opened, the brake fluid pressure is supplied from the brake fluid pressure generating mechanism 5 to the wheel cylinders 4a to 4d.
A return flow path for returning the brake hydraulic pressure to the reservoir tank 7 is provided in the upstream flow path of each of the wheel cylinders 4a to 4d.

Next, the reaction force generation mechanism 6 will be described.
The reaction force generation mechanism 6 is configured by a stroke simulator that simulates the amount of oil consumption and can absorb and consume the brake fluid pressure fed from the master cylinder 3.
The reaction force generating mechanism 6 is connected to a flow path that connects the first pressure generating chamber 3a and the electromagnetic valve 11, and includes, for example, a cylinder, a piston slidable in the cylinder, and an urging force for the piston. It is formed by force means or the like.
As a result, when the occupant depresses or returns the brake pedal 2, a reaction force (stepping force) having a preset characteristic can be applied to the occupant via the brake pedal 2. Since the reaction force acting on the occupant's leg from the brake pedal 2 and the pedaling force by which the occupant operates the brake pedal 2 are in a relation of action and reaction, the expression will be unified and described below.

The brake pedal 2 is provided with a stroke sensor 8 (operation amount detection means) that detects a pedal stroke St, which is an amount of depression or retraction of the brake pedal 2 by an occupant.
An occupant stroke operation amount St detected by the stroke sensor 8 is output as a detection signal to an ECU (Electronic Control Unit) 10 (control means).

Next, the ECU 10 will be described.
The ECU 10 includes a CPU (Central Processing Unit), a ROM, a RAM, an in-side interface, an out-side interface, and the like. The ROM stores various programs, data, and maps for controlling the pedal effort and braking force, and the RAM is provided with a processing area used when the CPU performs a series of processes.
The ECU 10 is electrically connected to the brake fluid pressure generating mechanism 5, the reaction force generating mechanism 6, the stroke sensor 8, and the electromagnetic valves 11 to 14, and is configured to be able to execute a deceleration control process and a pedaling force control process. ing.

First, the deceleration control process will be described.
As shown in FIG. 2, the ECU 10 has a pedaling force characteristic map M1.
As shown in the following equation (1), the sensation of the occupant is proportional to the logarithm of the stimulation intensity (Weber-Fechner's law). A is a sensory quantity, B is a physical quantity, k is a gain, and K is an integral constant.
A = klogB + K (1)
Therefore, the pedaling force characteristic map M1 is preset with a pedaling force characteristic L1 in which the pedaling force F by which the occupant operates the brake pedal 2 and the stroke St of the brake pedal 2 are in a logarithmic relationship.
The ECU 10 sets a pedaling force F that is an initial value based on the stroke St detected by the stroke sensor 8 and the pedaling force characteristic map M1.
Thereby, the relationship between the pedaling force F (operating force) of the brake pedal 2 perceived by the occupant and the stroke St (operation amount) of the brake pedal 2 can be made linear in terms of human perception characteristics, and the occupant can feel somatic sensation. The discrepancy between the perceived amount felt through the physical operation amount of the brake pedal 2 is avoided.

As shown in FIG. 3, the ECU 10 has a braking characteristic map M2.
The ECU 10 sets the pedal effort F set through the detected stroke St as the first pedal effort F1, and uses the first pedal effort F1 and the braking characteristic map M2 to reduce the deceleration corresponding to the target deceleration of the vehicle. D is set, and an operation command signal corresponding to the deceleration D is output to the brake fluid pressure generating mechanism 5 in a state where the solenoid valves 11 and 14 are closed and the solenoid valves 12 and 13 are opened.
Thereby, each wheel cylinder 4a-4d is driven and the braking of the deceleration D based on the braking characteristic map M2 is performed.
The ECU 10 corresponds to deceleration detection means.

The braking characteristic map M2 is defined by the first pedaling force F1 corresponding to the operating force of the brake pedal 2 by the occupant and the deceleration D of the vehicle. A braking characteristic T composed of a hysteresis T3 corresponding to a stepping force difference (offset amount) between the stepping characteristic T1 and the stepping back characteristic T2 is set.
The stepping characteristic T1 is set on the characteristic L2 in which the first pedaling force F1 when the occupant operates the brake pedal 2 and the vehicle deceleration D are in a logarithmic relationship when the first pedaling force F1 is less than the threshold value α. When F1 is greater than or equal to the threshold value α, it is set on the characteristic L3 that is higher than the characteristic L2 and has a linear relationship (the first pedaling force F1 and the deceleration D are proportional). The stepping-back characteristic T2 is offset from the stepping-characteristic T1 to the stepping force reduction side, for example, 15 to 20N.
In the present embodiment, the characteristic L3 is formed by a tangent line at the coordinates (α, β) of the characteristic L2.

The braking characteristic T is, for example, up to the threshold value β of the deceleration D required during emergency braking (the corresponding threshold value α of the first pedaling force F1), that is, during normal driving, the first pedaling force F1 and the vehicle deceleration D. Is a logarithmic relationship, it is possible to secure linearity between the amount of operation perceived by the occupant (the amount of perception of the first pedaling force F1) and the behavior of the vehicle (deceleration D), and a good operational feeling can be obtained. it can.
On the other hand, during emergency braking, the vehicle deceleration D is controlled to increase so as to be equal to or greater than the linearity relationship between the occupant's perceived operation amount and the behavior of the vehicle. Brake performance with good responsiveness can be exhibited.
As shown in FIG. 3, in the braking characteristic T, the remaining pedal force γ when the deceleration D in the stepping-back characteristic T2 is zero is set to 2N or more and 10N or less.
When the remaining pedal force γ is less than 2N, it is difficult to perceive the operation of the brake pedal 2 with the tactile sensation of the soles and the leg muscles. This is because the speed D cannot be recognized.

Further, as shown in FIG. 3, the ECU 10 sets the braking characteristic T (one-dot chain line) so that the hysteresis T3 becomes smaller as the deceleration D at the start of stepping back becomes lower, and the deceleration D at the start of stepping back is higher. The braking characteristic T (two-dot chain line) is set so that the hysteresis T3 increases as the time increases.
As a result, when the deceleration D at the start of stepping back is high when the amount of exercise is large and the function switching period of the main and antagonist muscles is long, the hysteresis T3 is increased and the function switching period of the main and antagonist muscles is short and the momentum is small. When the deceleration D at the start of stepping back is low, the response of the vehicle behavior is adapted to the muscle characteristics of the occupant by reducing the hysteresis T3.
The setting range of the hysteresis T3 is set to be equal to or greater than the remaining depression force γ and equal to or less than the depression start depression force δ (for example, 30 N) when the deceleration D in the depression characteristic T1 is zero.
This is to ensure the operability of the brake pedal 2 when the deceleration D is in the vicinity of zero while securing the function switching period between the main and antagonist muscles.

Next, the pedal force control process will be described.
As shown in FIG. 4, the ECU 10 has a braking stiffness characteristic map M3.
The ECU 10 sets the second pedaling force F2 using the detected stroke St, the set deceleration D and the braking stiffness characteristic map M3, and outputs an operation command signal corresponding to the second pedaling force F2 to the reaction force generating mechanism 6. Is output. The second pedaling force F2 set here is a reaction force that actually acts on the occupant, and is set as the occupant's pedaling force F necessary for operating the brake pedal 2.
In the braking rigidity characteristic map M3, the braking rigidity characteristic L4 is set by the deceleration D and the braking rigidity S. The braking rigidity S is obtained by substituting the second pedaling force F2 of the brake pedal 2 by the occupant and the stroke St of the brake pedal 2 into the following equation (2).
S = F2 / St (2)
As a precondition, the second pedaling force F2 and the deceleration D have a logarithmic relationship.

Here, the reason why the braking rigidity characteristic L4 is set will be described.
Usually, as shown in FIG. 5, the driving operation of the vehicle is performed by the occupant's stepping on the brake pedal 2 (t0 to t2), holding step (t2 to t3), stepping back step of the brake pedal 2 (t3 to t4), It consists of a stop holding process (t4 to t5) and a relapse progress of the vehicle (t5).
The spring constant indicates the physical operating characteristic of the brake pedal 2.
In the stepping-in process, the occupant moves his / her foot to the brake pedal 2 and consciously has a footrest area (t0 to t1) in which the mechanical play of the brake pedal 2 and the like is canceled by the operation of the brake pedal 2 (t0 to t1). There is a stepping area (t1 to t2) where the stepping operation is performed.
In the brake-by-wire mechanism, the coincidence between the end time of the footrest area and the play cancellation time (inflection point of the stroke St) and the coincidence between the start time of the deceleration D and the play cancellation time are determined by the brake pedal 2. Therefore, instead of using the first pedaling force F1, the second pedaling force F2 is set based on the braking stiffness characteristic L4 and the stroke St, and this second pedaling force F2 is set via the brake pedal 2. To the passengers.

As shown in FIG. 4, since the slope characteristic of the braking stiffness S is changed from negative to positive at the minimum point P of the braking stiffness characteristic L4, the minimum point P is determined by the occupant in the depression operation of the brake pedal 2. It is the recognition starting point. Therefore, the more the minimum point P shifts to the increase side of the deceleration D, the slower the recognition of the stepping by the occupant, in spite of the fact that the deceleration D is actually generated in the vehicle. There is a discrepancy between behavior and operation recognition. Therefore, from the viewpoint of operability, the minimum point P is set to be the deceleration D in the near zero region.
In this embodiment, the minimum point P is set to be a deceleration D slightly larger than the minimum threshold value ε of the deceleration D that can be perceived by the occupant. As a result, the occupant can foresee the start of actual depression operation of the brake pedal 2 (recognition of play cancellation) by the operation with the negative braking rigidity S while improving the braking response of the vehicle.

Further, the inclination angle on the increasing side of the minimum point P of the braking rigidity characteristic L4 is set to, for example, 0.10 to 0.30 ((N / mm) / (m / s ² )).
When the inclination angle of the braking stiffness characteristic L4 is less than 0.10, it is difficult to perceive the feeling of operation of the brake pedal 2 (the sponge feeling is high) because the response of the brake pedal 2 by the occupant is small, and 0.30 This is because the pedaling force F required for the operation of the brake pedal 2 is high, the pedaling of the brake pedal 2 is difficult (the feeling of stepping on the plate is high) and the operability is lowered.

Next, functions and effects of the vehicle brake control device 1 will be described.
According to the braking control apparatus 1 according to the first embodiment, the braking characteristic T is set by the first pedaling force F1 of the brake pedal 2 and the deceleration D of the vehicle, and the pedaling force T1 is greater than the pedaling characteristic T1. Since the ECU 10 sets the braking characteristic T including the stepping-back characteristic T2 offset by the hysteresis T3 on the decrease side, the change tendency of the stepping-back characteristic T2 and the change tendency of the stepping characteristic T1 can be made substantially the same. When the occupant shifts from the stepping operation to the stepping back operation, it is possible to avoid a sense of discomfort. Since the ECU 10 decreases the hysteresis T3 of the braking characteristic T as the deceleration D at the start of stepping back decreases and controls the braking fluid pressure generating mechanism 5 based on the braking characteristic T, the function of the main muscle and antagonist muscle is large. When the switching period becomes long, the hysteresis T3 can be increased, and when the function switching period between the active muscle and the antagonistic muscle becomes short and the function switching period becomes short, the hysteresis T3 can be decreased. As a result, the response of the vehicle behavior Can be adapted to the muscle characteristics of the occupant.

  Since the remaining pedal force γ when the deceleration D in the stepping-back characteristic T2 is zero is set to 2N or more and 10N or less, the operability of the brake pedal 2 in the region where the deceleration D is near zero can be ensured.

  The hysteresis T3 is set to be equal to or greater than the remaining pedaling force γ when the deceleration D in the stepping-back characteristic T2 is zero and equal to or smaller than the pedaling start pedaling force δ when the deceleration D in the stepping characteristic T1 is zero. While ensuring the function switching period, the operability of the brake pedal 2 in the region where the deceleration D is near zero can be ensured.

  The braking characteristic T is set so that the first pedaling force F1 and the deceleration D are in a logarithmic relationship, so that the passenger can perceive the deceleration D proportional to the first pedaling force F1, and the brake pedal 2 Operability can be improved.

Next, a modified example in which the embodiment is partially changed will be described.
1] In the above embodiment, when the first pedaling force is less than the threshold value, the first pedaling force by which the occupant operates the brake pedal and the deceleration of the vehicle are set on the logarithmic relationship, and the first pedaling force is equal to or greater than the threshold value. In this case, the example of the braking characteristic higher than the characteristic and set on the linear relation characteristic has been described. However, a braking characteristic in which the first pedaling force and the deceleration of the vehicle are simply in a logarithmic relationship may be used.

2] In the above-described embodiment, the example in which the second pedaling force is set using the deceleration set based on the braking stiffness characteristic map, the stroke, and the braking characteristic map has been described. However, a deceleration detecting means such as a speed sensor is provided, The second pedaling force may be set using the braking stiffness characteristic map, the stroke, and the detected deceleration.

3) In addition, those skilled in the art can implement the present invention in a form in which various modifications are added to the above-described embodiment or a combination of the above-described embodiments without departing from the spirit of the present invention. Various modifications are also included.

DESCRIPTION OF SYMBOLS 1 Braking control apparatus 2 Brake pedal 5 Braking hydraulic pressure generation mechanism 6 Reaction force generation mechanism 8 Stroke sensor 10 ECU
T Braking characteristics T1 Depression characteristics T2 Retraction characteristics T3 Hysteresis

Claims (3)

An operation amount detection means for detecting an operation amount of the brake pedal, a reaction force generation mechanism that generates a reaction force of the brake pedal based on the operation amount of the brake pedal, a braking force generation mechanism that generates a braking force on the wheels, In a vehicle braking control device comprising the reaction force generating mechanism and a control means capable of controlling the braking force generating mechanism,
A braking characteristic set by a pedaling force corresponding to a reaction force of the brake pedal and a deceleration of the vehicle, and comprising a pedaling characteristic and a stepping-back characteristic offset from the pedaling characteristic by a hysteresis toward the pedaling force decreasing side. Having braking characteristic setting means for setting the characteristic;
The remaining pedal force when the deceleration in the stepping-back characteristic is zero is set to 2N or more and 10N or less,
The vehicular braking control device, wherein the control means reduces the hysteresis of the braking characteristic as the deceleration at the start of stepping back decreases, and controls the braking force generation mechanism based on the braking characteristic. An operation amount detection means for detecting an operation amount of the brake pedal, a reaction force generation mechanism that generates a reaction force of the brake pedal based on the operation amount of the brake pedal, a braking force generation mechanism that generates a braking force on the wheels, In a vehicle braking control device comprising the reaction force generating mechanism and a control means capable of controlling the braking force generating mechanism,
A braking characteristic set by a pedaling force corresponding to a reaction force of the brake pedal and a deceleration of the vehicle, and comprising a pedaling characteristic and a stepping-back characteristic offset from the pedaling characteristic by a hysteresis toward the pedaling force decreasing side. Having braking characteristic setting means for setting the characteristic;
The hysteresis is set to be equal to or greater than the remaining pedal effort when the deceleration is zero in the stepping-back characteristic and less than or equal to the depression start pedaling force when the deceleration is zero in the depression characteristic,
It said control means, drive the dual brake control apparatus shall be the controls said braking force generating mechanism based on the brake characteristics with hysteresis to reduce the braking characteristic the lower the deceleration the releasing initiation. An operation amount detection means for detecting an operation amount of the brake pedal, a reaction force generation mechanism that generates a reaction force of the brake pedal based on the operation amount of the brake pedal, a braking force generation mechanism that generates a braking force on the wheels, In a vehicle braking control device comprising the reaction force generating mechanism and a control means capable of controlling the braking force generating mechanism,
A braking characteristic set by a pedaling force corresponding to a reaction force of the brake pedal and a deceleration of the vehicle, and comprising a pedaling characteristic and a stepping-back characteristic offset from the pedaling characteristic by a hysteresis toward the pedaling force decreasing side. Having braking characteristic setting means for setting the characteristic;
The braking characteristic is set so that the pedaling force and the deceleration are in a logarithmic relationship,
It said control means, drive the dual brake control apparatus shall be the controls said braking force generating mechanism based on the brake characteristics with hysteresis to reduce the braking characteristic the lower the deceleration the releasing initiation.