JP4843967B2 - Vehicle deceleration control device - Google Patents

Description

  The present invention relates to a vehicle deceleration control device, and more particularly to a vehicle deceleration control device that performs vehicle deceleration control by shifting a transmission to a relatively low speed gear stage or gear ratio.

  A shift point control technique is known in which, when vehicle deceleration control is performed based on the size of a corner ahead of a vehicle, the transmission is downshifted, and deceleration due to engine braking force is applied to the vehicle.

  For example, Japanese Patent Laid-Open No. 2000-145937 (Patent Document 1) discloses a technique for performing downshift control according to road conditions based on road information stored in a navigation system.

JP 2000-145937 A

  In a vehicle deceleration control device that performs deceleration control by shifting the transmission to a relatively low speed gear ratio or gear ratio based on the size of the corner at the front of the vehicle, the vehicle stably turns the corner. It is desired to control so that it is possible.

  SUMMARY OF THE INVENTION An object of the present invention is a vehicle deceleration control device that controls deceleration by shifting a transmission based on the size of a corner, and is capable of performing deceleration control suitable in terms of vehicle stability. A vehicle deceleration control device is provided.

A vehicle deceleration control device according to the present invention is a vehicle deceleration control device that performs deceleration control by shifting a transmission based on the shape of a corner ahead of the vehicle, based on the shape of the corner and the vehicle speed. The vehicle stabilizes the corner based on the generated lateral force estimating means for estimating the lateral force generated in the vehicle turning around the corner, and the vehicle speed and the deceleration due to the gear stage or gear ratio of the transmission. A threshold value estimation means for estimating a threshold value related to the turning state of the vehicle for turning automatically, and the deceleration control based on the lateral force generated in the estimated vehicle and the estimated threshold value necessity, and, and means for determining a gear position or speed ratio of the transmission destination of the transmission when the deceleration control is performed, and, said means for determining, in a case where the deceleration control, A deceleration closest to the lateral force a gear position or speed ratio equal to or less than the estimated threshold corner required deceleration for turning by the turning state that occur serial estimated vehicle The gear stage or gear ratio is selected as the temporary gear stage or the temporary gear ratio, and the gear stage or gear shift that is the gear ratio on the high speed stage or the high speed stage side that is equal to or higher than the temporary gear stage or the temporary gear ratio and that has the maximum speed. The ratio is determined as a shift speed or a gear ratio of the transmission destination of the transmission.

  In the vehicle deceleration control apparatus according to the present invention, the threshold value estimation means further estimates the threshold value based on the slipperiness of the road surface of the corner.

  In the vehicle deceleration control apparatus according to the present invention, the turning state estimation means changes the estimation result of the turning state of the vehicle based on the position detection accuracy of the navigation system device of the vehicle.

  According to the present invention, in a vehicle deceleration control device that controls deceleration by shifting a transmission based on the size of a corner, it is possible to perform deceleration control suitable for the stability of the vehicle. It becomes.

  Hereinafter, an embodiment of a vehicle deceleration control device of the present invention will be described in detail with reference to the drawings.

(First embodiment)
The first embodiment will be described with reference to FIGS. 1 to 8.

  In a vehicle deceleration control device that performs deceleration control by downshifting a transmission based on the size of a corner ahead of the vehicle, a downshift command is output and the vehicle turning determination is made before the gearshift is started. It is considered that the shift is canceled when the tire slip determination is made. However, in this case, a shift command that is finally canceled is output. Further, in this case, there is a possibility that the shift is executed halfway. If shifting is executed halfway, a change in deceleration or a change in engine speed may occur, which may cause the driver to feel uncomfortable. It is desirable that such a shift command is not output from the beginning.

  In the present embodiment, whether or not it is reasonable from the viewpoint of vehicle stability to issue a shift command to a specific shift stage is determined before the shift command is output. That is, after a reasonable shift speed is obtained from the viewpoint of vehicle stability, a shift command for the shift speed is output. Thus, in a vehicle deceleration control device that controls deceleration by shifting the transmission based on the size of the corner, it is possible to perform optimum deceleration control in terms of vehicle running stability. .

  In this embodiment, in corner control, the generated lateral force and deceleration force at the time of turning are estimated from the shape of the road ahead, the vehicle speed and the deceleration, and obtained from the tire friction circle determined from this generated lateral force, the estimated deceleration force and the driving environment. The required lateral force is compared, and the necessity of corner control and the regulated gear position are determined based on the comparison result.

As the configuration of the present embodiment, (1) to (4) are assumed as will be described in detail below.
(1) A device that controls the deceleration by shifting at least the shift stage of the automatic transmission when the driver's intention to decelerate is detected based on the driving environment (including the size of the corner and the road gradient).
(2) Means for estimating the lateral force (F ″) and deceleration force (F) generated during a turn from the road shape, vehicle speed, and deceleration ahead of the vehicle.
(3) Means for estimating the limit lateral force (F ′) from the estimated deceleration force (F) and the traveling environment.
(4) Means for comparing the generated lateral force (F ″) with the limit lateral force (F ′) to determine the presence / absence of deceleration control, the regulated shift speed or the gear ratio, and to output the result.

  In FIG. 2, reference numeral 10 is a stepped automatic transmission, and 40 is an engine. The automatic transmission 10 is capable of six-speed shifting by controlling the hydraulic pressure by energization / non-energization of the solenoid valves 121a, 121b, and 121c. In FIG. 2, three electromagnetic valves 121a, 121b, and 121c are illustrated, but the number of electromagnetic valves is not limited to three. The solenoid valves 121a, 121b, and 121c are driven by a signal from the control circuit 130.

  The throttle opening sensor 114 detects the opening of the throttle valve 43 disposed in the intake passage 41 of the engine 40. The engine speed sensor 116 detects the speed of the engine 40. The vehicle speed sensor 122 detects the rotation speed of the output shaft 120c of the automatic transmission 10 that is proportional to the vehicle speed. The shift position sensor 123 detects the shift position. The pattern select switch 117 is used when instructing a shift pattern. The acceleration sensor 90 detects vehicle deceleration (deceleration acceleration).

  The road gradient measurement / estimation unit 118 can be provided as a part of the CPU 131. The road gradient measurement / estimation unit 118 can measure or estimate the road gradient based on the acceleration detected by the acceleration sensor 90. Further, the road gradient measuring / estimating unit 118 may store the acceleration on the flat road in the ROM 133 in advance and obtain the road gradient by comparing with the acceleration actually detected by the acceleration sensor 90.

  The navigation system device 95 has a basic function of guiding the host vehicle to a predetermined destination, and includes an arithmetic processing device and information (map, straight road, curve, uphill / downhill, highway) necessary for traveling the vehicle. Etc.), a first information detection device including a geomagnetic sensor, a gyrocompass, and a steering sensor, and a current position of the vehicle by radio navigation. It is for detecting a position, road conditions, etc., and is provided with a second information detection device including a GPS antenna and a GPS receiver.

  The tire slip determination unit 91 detects the presence or absence of tire slip. The tire slip determination unit 91 performs various conditions, for example, a rotational speed (driven wheel speed) of a front wheel (not shown) detected by a front wheel speed sensor (not shown) and a rear wheel (detected by a vehicle speed sensor 122). The presence / absence of tire slip is detected based on the difference in rotational speed (drive wheel speed).

  The specific method of detecting the presence or absence of tire slip by the tire slip determination unit 91 is not particularly limited, and a known method can be appropriately employed. For example, in addition to the wheel speed difference before and after the above, the rate of change of wheel speed, ABS (anti-lock brake system), TRS (traction control system) and VSC (vehicle stability control) operation The presence or absence of tire slip can be detected using at least one of the relationship between the history, the acceleration of the vehicle, and the wheel slip ratio.

  The road surface μ detection / estimation unit 92 detects or estimates the slipperiness of the road surface represented by the road surface friction coefficient μ (whether the road surface is a low μ road). Here, the low μ road includes a bad road (including a case where the road surface has large unevenness or a step on the road surface). That is, the road surface μ detection / estimation unit 92 calculates the friction coefficient μ of the traveling road surface, and determines whether the road is a low μ road depending on whether the calculated friction coefficient μ exceeds a predetermined threshold value. Is determined.

  The road surface μ detection / estimation unit 92 predicts whether the road surface is a low μ road, based on information (navigation information, etc.) about the road surface scheduled to travel in the future. Here, the navigation information includes information on road surfaces (for example, non-paved roads) recorded in advance on a storage medium (DVD, HDD, etc.) as in the navigation system device 95, as well as past actual driving and other information. Information (including information indicating road conditions and information indicating weather conditions) obtained through communication (including vehicle-to-vehicle communication and road-to-vehicle communication) with other vehicles and communication centers. Such communications include road traffic information communication systems (VICS) and so-called telematics.

  The control circuit 130 is a signal indicating detection results of the throttle opening sensor 114, the engine speed sensor 116, the vehicle speed sensor 122, the shift position sensor 123, the acceleration sensor 90, the tire slip determination unit 91, and the road surface μ detection / estimation unit 92. , A signal indicating the switching state of the pattern select switch 117 is input, and a signal from the navigation system device 95 is input.

  The control circuit 130 is configured by a known microcomputer and includes a CPU 131, a RAM 132, a ROM 133, an input port 134, an output port 135, and a common bus 136. The input port 134 includes signals from the sensors 114, 116, 122, 123, and 90, signals from the switch 117, a navigation system device 95, a tire slip determination unit 91, and a road surface μ detection / estimation unit 92. Signals from each are input. Solenoid valve driving units 138a, 138b, and 138c are connected to the output port 135.

  The ROM 133 stores in advance a program in which the operations (control steps) shown in the flowchart of FIG. 1 are described, and a shift map for shifting the shift stage of the automatic transmission 10 and a shift control operation (not shown). ) Is stored.

  The control circuit 130 determines the gear stage of the automatic transmission 10 based on the accelerator opening corresponding to the actual engine load and the vehicle speed from the shift map stored in advance, and establishes the determined gear stage. Automatic shift control for controlling the solenoid valves 121a to 121c of the hydraulic control circuit provided in the automatic transmission 10 is executed.

Next, the operation of this embodiment will be described.
In the following, a description will be given of a case where deceleration control (corner control) is performed by shifting the shift stage of the automatic transmission 10 based on the size of the corner.

  FIG. 7 is a chart for explaining the deceleration control of the present embodiment. In FIG. 7, the abscissa indicates the distance, and the control execution boundary line Lc, the required deceleration 401, the target turning vehicle speed Vreq, the road shape top view, and the point a where the accelerator is OFF (the accelerator opening is fully closed). , Deceleration force (F) 13, running resistance 14, vehicle speed 11, limit lateral force (F ′) 19, and generated lateral force (F ″) 21 are shown.

  As shown in FIG. 7, the previous corner 402 exists from a point 403 to a point 404. A target turn corresponding to the radius (or curvature) R405 of the corner 402 at a point b offset from the entrance 403 of the corner 402 by a predetermined amount in order to turn the corner 402 at a predetermined desired turn G. It has to be decelerated to the vehicle speed Vreq. That is, the target turning vehicle speed Vreq is a value corresponding to R405 of the corner 402.

[Step S10]
In step S10 of FIG. 1, the control circuit 130 determines whether or not the accelerator is in an OFF state (fully closed) based on a signal from the throttle opening sensor 114. If it is determined as a result of step S10 that the accelerator is in an OFF state, the process proceeds to step S20. When the accelerator is fully closed (step S10-Y), it is determined that the driver intends to decelerate, and the deceleration control of this embodiment is performed. On the other hand, if it is not determined that the accelerator is in the OFF state, the process proceeds to step S110. As described above, in FIG. 7, the accelerator opening is zero (fully closed) at the position (time point) a.

[Step S20]
In step S20, the control circuit 130 checks the flag F. If the flag F is 0, the process proceeds to step S30. If the flag F is 1, the process proceeds to step S60. If the flag F is 2, the process proceeds to step S70. When this control flow is executed, the flag F is initially 0, so the process proceeds to step S30.

[Step S30]
In step S30, the control circuit 130 determines whether or not this control is necessary based on, for example, the control execution boundary line Lc. In the determination, in FIG. 7, if it is located above the control execution boundary line Lc in relation to the current vehicle speed and the distance L to the entrance 403 of the corner 402, it is determined that this control is necessary, and the control execution boundary is determined. If it is located below the line Lc, it is determined that this control is unnecessary. As a result of the determination in step S30, if it is determined that this control is necessary, the process proceeds to step S40. If it is determined that this control is not necessary, this control flow is returned.

  The control execution boundary line Lc is a relationship between the current vehicle speed and the distance to the point b just before the entrance 403 of the corner 402, as long as the deceleration exceeding the deceleration set by the normal braking does not act on the vehicle. This is a line corresponding to a range in which the target turning vehicle speed Vreq cannot be reached at the point b before the entrance 403 of the corner 402 (the corner 402 cannot be turned with the desired turning G). That is, when the vehicle is positioned above the control execution boundary line Lc, in order to reach the target turning vehicle speed Vreq at the point b before the entrance 403 of the corner 402, the deceleration by the normal braking set in advance is exceeded. It is necessary for the deceleration to act on the vehicle.

  Therefore, when the position is higher than the control execution boundary line Lc, the deceleration control corresponding to the size of the corner of the present embodiment is executed (step S50), and the braking of the driver by the increase of the deceleration is performed. Even if there is no operation amount or the operation amount is relatively small (even if the foot brake is stepped on only a little), the target turning vehicle speed Vreq can be reached at the point b before the entrance 403 of the corner 402. Yes.

  As the control execution boundary line Lc of the present embodiment, a control execution boundary line used for shift point control corresponding to a conventional general corner R can be applied as it is. The control execution boundary line Lc is created by the control circuit 130 based on the data input from the navigation system device 95 and indicating the distance between R405 of the corner 402 and the corner.

  In the present embodiment, in FIG. 7, the time point corresponding to the symbol a at which the accelerator opening is zero is located above the control execution boundary line Lc, so it is determined that this control is necessary (step S30-Y). ), Go to step S40. The contents of step S40 will be described with reference to FIG. As shown in FIG. 3, step S40 includes steps S41 to S46.

[Step S41]
In step S <b> 41 of FIG. 3, the control circuit 130 obtains a temporary shift stage for the shift control (shift down) of the automatic transmission 10. In determining the temporary shift speed, first, the required deceleration is obtained, and then the temporary shift speed is determined based on the required deceleration. Hereinafter, the calculation of the required deceleration will be described as (A), and then the determination of the temporary gear position will be described as (B).

(A) Calculation of Required Deceleration The required deceleration is calculated by the control circuit 130. The necessary deceleration is a deceleration required to turn the other corner at a predetermined desired turning G (in order to enter the corner at a desired vehicle speed Vreq). In FIG. 7, the necessary deceleration is indicated by reference numeral 401.

  In order to decelerate from the vehicle speed at the location a where the accelerator is determined to be fully closed in step S10 to the target turning vehicle speed Vreq required at the point b before the entrance 403 of the corner 402, this is indicated by the required deceleration 401. Such deceleration is required. The control circuit 130 is based on the current vehicle speed input from the vehicle speed sensor 122, the distance from the current position to the entrance 403 of the corner 402 (point b before) and the R405 of the corner 402, which are input from the navigation system device 95. The necessary deceleration 401 is calculated.

(B) Determination of Temporary Shift Stage In the ROM 133, vehicle characteristic data indicating the deceleration G for each vehicle speed at each shift stage when the accelerator is OFF as shown in FIG. 8 is registered in advance.

  Here, assuming that the output rotational speed is 1000 [rpm] and the required deceleration 401 is −0.12 G, in FIG. 8, this corresponds to the vehicle speed when the output rotational speed is 1000 [rpm]. In addition, it can be seen that the shift speed at which the deceleration closest to −0.12G of the required deceleration 401 is the fourth speed. Thus, in the case of the above example, in step S41, the provisional shift speed is determined to be the fourth speed.

  In this case, the shift speed that is the closest to the required deceleration 401 is selected as the temporary shift speed. However, the temporary shift speed is the required deceleration 401 or lower (or higher) and the required deceleration. A gear position that provides the closest deceleration to 401 may be selected. After step S41, step S42 is executed.

[Step S42]
In step S42, the control circuit 130 predicts how the vehicle speed and deceleration force (F) will change in the future. In FIG. 5, reference numeral 11 indicates a vehicle speed, reference numeral 12 indicates a shift speed, reference numeral 13 indicates a deceleration force (F) by the shift speed, reference numeral 14 indicates a running resistance, and reference numeral 15 indicates a deceleration acting on the vehicle. (Α) is shown.

  In step S42, a deceleration force converted value 13 of the deceleration torque for each gear stage 12 corresponding to the current vehicle speed 11 is obtained. The deceleration force (F) 13 by the gear stage 12 is a function of the vehicle speed 11. Further, the running resistance 14 is obtained based on the vehicle speed 11 and the road gradient obtained by the road gradient measuring / estimating unit 118. In other words, from the current vehicle speed 11, the deceleration torque (deceleration force conversion value 13) and the running resistance 14 by a certain gear stage 12 at the present time are obtained. The sum of the deceleration force (F) 13 and the running resistance 14 is obtained as the vehicle deceleration (α) 15.

  Based on the vehicle deceleration (α) 15, the vehicle speed V ′ (11) and the travel distance (ΔL) 17 after the predetermined short time Δt has elapsed can be estimated. From the estimated vehicle speed V ′ (11), the deceleration force (F) 13 and the running resistance 14 at that time are estimated, and the vehicle deceleration (α) 15 is obtained from the deceleration force (F) 13 and the running resistance 14. Presumed. In this way, by repeating the calculation every time the predetermined time (Δt) elapses, future changes in the vehicle speed 11 and the deceleration force (F) 13 are estimated. That is, as shown in FIG. 7, a change mode of the vehicle speed 11 and the deceleration force (F) 13 from the current point (a point where the accelerator is turned off) a is obtained. Following step S42, step S43 is performed.

[Step S43]
In step S <b> 43, the control circuit 130 obtains a limit lateral force (F ′) 19 based on the deceleration force (F) 13 estimated in step S <b> 42 and the traveling environment 18. The traveling environment 18 includes the road surface μ obtained by the road surface μ detection / estimation unit 92 and the road gradient obtained by the road gradient measurement / estimation unit 118. Even if the deceleration force (F) 13 is the same, the limit lateral force (F ′) 19 varies depending on the traveling environment 18. This corresponds to the fact that the radius of the tire friction circle shown in FIG. 4 varies depending on the traveling environment 18 such as the road surface μ.

  When the size (radius) of the tire friction circle is determined by the traveling environment 18 as shown in FIG. 4, the critical lateral force (F ′) is determined from the size of the tire friction circle and the deceleration force (F) 13. ) 19 is obtained (see FIG. 5). That is, the critical lateral force (F ′) 19 is obtained on the assumption that the resultant force 31 of the deceleration force (F) 13 and the critical lateral force (F ′) 19 does not exceed the tire friction circle. As shown in FIG. 7, the limit lateral force (F ′) 19 is obtained based on the deceleration force (F) 13 and the traveling environment 18 at each point from the current point a. Following step S43, step S44 is performed.

[Step S44]
In step S44, in the control circuit 130, as shown in FIG. 6, the lateral force (F ″) generated in the vehicle based on the destination road shape 23 (including the corner R405) and the vehicle speed 11 estimated above. 21 is obtained by the following equation.

  In the above equation, R (corner turning radius) and ω (angular velocity) are obtained from the destination road shape 23 and the vehicle speed 11, which are updated every predetermined time (Δt), respectively. In the information input from the navigation system device 95, the destination road shape 23 is the initial vehicle position (point a in FIG. 7) where the calculation of FIG. 3 is started, and the travel distance (ΔL) obtained in step S42. 17 from the above. As shown in FIG. 7, the generated lateral force (F ″) 21 is obtained based on the vehicle speed 11 and the ahead road shape 23 (including the corner R405) at each point from the current point a. Following step S44, step S45 is performed.

[Step S45] and [Step S46]
In step S45, the control circuit 130 obtains the maximum shift amount that is a high speed stage that is equal to or higher than the temporary speed stage obtained in step S41. Based on the maximum shift amount, the gear position is determined (step S46). Here, as shown in FIG. 7, the maximum shift amount is obtained in a range in which the generated lateral force (F ″) 21 does not become larger than the limit lateral force (F ′) 19 while turning the corner 402.

  For example, when the gear position at the time when the accelerator is turned off is the sixth speed and the temporary gear position obtained in step S41 is the third speed, the generated lateral force (F ″) 21 is limited at the third speed. If the generated lateral force (F ″) 21 does not become greater than the limit lateral force (F ′) 19 at the fourth speed, the fourth speed is determined as the gear position. (Step S46). Further, for example, when the provisional shift speed obtained in step S41 is the third speed, the generated lateral force (F ″) 21 is larger than the limit lateral force (F ′) 19 at the third speed and the fourth speed. If the generated lateral force (F ″) 21 is greater than the limit lateral force (F ′) 19 at the fifth speed, the fourth speed is determined as the gear position (step S46).

  As shown in FIG. 7, when the generated lateral force (F ″) 21 is smaller than the limit lateral force (F ′) 19, it is determined that there is no problem as the vehicle behavior (running stability). Therefore, the gear stage is determined as the downshift destination gear stage (step S46). On the other hand, when the generated lateral force (F ″) 21 becomes larger than the limit lateral force (F ′) 19, the generated lateral force (F ″) 21 does not become larger than the limit lateral force (F ′) 19. A gear that satisfies the above criteria is obtained (steps S45 and S46).

  In the above, when the maximum shift amount is not obtained in step S45 based on the above criterion that the generated lateral force (F ″) 21 does not become larger than the limit lateral force (F ′) 19, the present embodiment is performed. The downshift control by the form corner control is not performed. In step S45, the high speed stage that is equal to or higher than the temporary shift speed determined in step S41 is selected, and the low speed stage is not selected from the temporary shift speed for the following reason. Since the temporary shift speed is determined so that an appropriate deceleration can be obtained when turning the corner (appropriate vehicle speed can be obtained), the deceleration is excessive at a lower speed than the temporary shift speed. It is. In step S46, the generated lateral force (F ″) 21 and the limit lateral force (F ′) 19 are compared. Instead, the deceleration force (F) 13 and the limit lateral force ( F ′) 19 and the resultant force 31 can be compared with the tire friction circle. Following step S46, step S50 of FIG. 1 is performed.

[Step S50]
In step S50, the control circuit 130 outputs a shift command related to the shift speed determined in step S46. That is, a downshift command (shift command) is output from the CPU 131 of the control circuit 130 to the solenoid valve driving units 138a to 138c. In response to the downshift command, the solenoid valve driving units 138a to 138c energize or de-energize the solenoid valves 121a to 121c. As a result, the automatic transmission 10 performs a shift instructed by the downshift command.

  When the downshift command is determined by the control circuit 130 at the location (time point) corresponding to the symbol a in FIG. Output simultaneously. After step S50, the process proceeds to step S60.

[Step S60]
In step S60, the control circuit 130 determines whether or not the vehicle has entered the corner 402 (vehicle turning determination). The control circuit 130 determines in step S60 based on the size of the lateral G of the vehicle. Alternatively, based on the data input from the navigation system device 95 and indicating the current position of the vehicle and the position of the entrance 403 of the corner 402, the determination in step S60 is performed. If the result of determination in step S60 is that entry has started to the corner 402, the process proceeds to step S70, and if not, the process proceeds to step S140.

  In the first stage in which this control flow is implemented, since the vehicle has not entered the corner 402 (step S60-N), the presence or absence of tire slip is determined in step S140.

[Step S140]
In step S140, the control circuit 130 determines the presence or absence of tire slip based on the signal input from the tire slip determination unit 91. As a result of the determination, if it is determined that there is a tire slip exceeding a predetermined value, the process proceeds to step S70, and if not, the process proceeds to step S150.

  In step S140, it is determined whether or not the road surface is a low μ road based on not only the presence / absence of tire slip but also the signal input from the road surface μ detection / estimation unit 92. If it is determined that there is a low μ road, the process proceeds to step S70. If it is determined that the road is not in any case, the process may proceed to step S150.

[Step S70]
In step S70, the control circuit 130 restricts new upshifts and downshifts. Upshifting to a relatively high speed gear stage is restricted relative to the gear stage according to the latest gear shift command (including the downshift command output in step S50). Further, regarding downshifting, downshifting to a relatively low speed gear stage is restricted as compared with the gear stage according to the latest gear shift command. This is to prevent an increase in deceleration and contribute to vehicle stability.

  In step S70, if the shift related to the latest shift command ends (or a certain point before the shift end), the engagement side of the automatic transmission 10 is canceled to cancel the shift. Reduce clutch hydraulic pressure. In this case, the shift to be canceled can be limited to downshift. After step S70, the process proceeds to step S80.

[Step S150]
In step S150, the flag F is set to 1 and this control flow is reset. In the control flow again, when the accelerator is fully closed (step S10-Y), since the flag F is 1 (step S20-1), the process proceeds to step S60 and is repeated until the condition of step S60 is satisfied. It is.

[Step S80]
In step S80, the control circuit 130 determines whether or not the vehicle has exited the corner 402. The control circuit 130 determines whether or not the vehicle has escaped the corner 402 based on the lateral G acting on the vehicle. Alternatively, based on the data input from the navigation system device 95 and indicating the current position of the vehicle and the position of the exit 404 of the corner 402, the determination in step S80 is performed. As a result of the determination in step S80, if it is after exiting the corner 402, the process proceeds to step S90, and if not, the process proceeds to step S160.

  Since the vehicle has not escaped from the corner 402 at the first stage in which this control flow is performed (step S80-N), the flag F is set to 2 in step S160, and this control flow is reset. In the control flow again, when the accelerator is fully closed (step S10-Y), since the flag F is 2 (step S20-2), the shift restriction is kept (step S70), and the process goes to step S80. The process is repeated until the condition of step S80 is satisfied. If the condition of step S80 is satisfied (step S80-Y), the process proceeds to step S90.

[Step S90]
In step S90, the shift restriction is canceled by the control circuit 130. As a result, the restriction on the upshift and the downshift performed in step S70 is released. Following step S90, step S100 is performed.

[Step S100]
In step S100, the control circuit 130 sets the flag F to 0. Following step S100, the control flow is reset.

[Step S110] to [Step S130]
If the accelerator is not fully closed (step S10-N), it is determined whether cornering is being performed (step S110). If the result of this determination is cornering (step S110-Y), this control flow is reset. When cornering is not in progress (step S110-N), the shift restriction is canceled (step S120), and the flag F is cleared and reset (step S130). Note that in the initial state when this control is started, the shift is not restricted and the flag F is also 0, so it remains as it is. If the accelerator is stepped on until a negative determination is made in step S60 or a negative determination is made in step S80, and a positive determination is made in each case, the same determination as above in step S110 Is performed, and treatment is performed as necessary.

  According to this embodiment described above, the following effects can be obtained.

  In FIG. 7, when the accelerator is turned off at point a, the vehicle speed is equal to or higher than the control execution boundary line Lc, and thus corner control is performed (step S30-Y). As described above, it is possible to estimate changes in the deceleration force (F) 13 and the vehicle speed 11 (step S42). Based on the deceleration force (F) 13 and the travel environment 18 at each point, a limit lateral force (F ') 19 is obtained (step S43). Based on the vehicle speed 11 at each point and the destination road shape 23 (including corner R405), a generated lateral force (F ″) 21 that will be generated is obtained (step S44). When the generated lateral force (F ″) 21 is smaller than the limit lateral force (F ′) 19, it is determined that there is no problem in the vehicle behavior (running stability). Downshift control to the first gear (step S45 to step S50).

  As shown in FIG. 7, there is a time delay (ta) from the time when the accelerator is turned off or the time when the shift command is output (a) until the deceleration occurs, or the inertia torque (Ge) ) Occurs, the deceleration force (F) 13 during this period (ts) can be given as a value indicated by a broken line.

  That is, as described with reference to FIG. 5, the deceleration force (F) 13 used when the vehicle deceleration (α) 15 and the limit lateral force (F ′) 19 are obtained in steps S42 and S43, respectively. As an example, the speed reduction command (F) 13 obtained from the vehicle speed 11 (step S42) is not used, but a speed change command is output for the speed reduction power (F) 13 in the predetermined section ts in FIG. A value (a value corresponding to the broken line in the predetermined section ts in FIG. 7) set in advance according to the elapsed time from the time point (reference a in FIG. 7) is used. This makes it possible to take into account an increase in deceleration during the inertia phase during the shift.

  Further, in consideration of the detection accuracy related to the current position of the vehicle detected by the navigation system device 95, the generation point of the generated lateral force (F ″) 21 is set in front and calculated by the maximum amount of the detection error. It is preferable. That is, in FIG. 7, the generated lateral force (F ″) 21 is set to be generated from the entrance 403 (point c) of the corner 402, and the position detection error by the navigation system device 95 is not taken into consideration. However, in consideration of the detection error, it is preferable to set the generation point of the generated lateral force (F ″) 21 in the direction b in the figure.

  In this case, the position detection accuracy by the navigation system device 95 varies depending on the travel distance from the time when the map matching of the navigation system device 95 is performed. For this reason, the amount of setting the generated lateral force (F ″) 21 to the near side (how far from the point c) depends on the distance traveled from the time when the map matching of the navigation system device 95 was performed. It is possible to change.

  According to the present embodiment, as described above, after obtaining the deceleration force (F) 13, the limit lateral force (F ′) 19, and the generated lateral force (F ″) 21 for a certain shift stage, the vehicle The optimum gear position is determined in terms of stability. Conventionally, when performing deceleration control corresponding to the other corner, there has been an idea that a smaller deceleration force (F) 13 acting on the vehicle is better in terms of vehicle stability. In contrast, in the present embodiment, as shown in the relationship between the tire friction circle, the deceleration force (F) 13 and the limit lateral force (F ′) 19 (the resultant force 31) in FIG. 4, the deceleration force (F). 13 and the limit lateral force (F ′) 19 are taken into consideration, and an optimal gear position in terms of vehicle stability can be selected. That is, the optimum gear is selected in consideration of the following points.

  When the deceleration force (F) 13 is large enough to exceed the tire friction circle, it is disadvantageous in terms of vehicle stability, but on the other hand, the vehicle speed 11 decreases due to the application of the deceleration force (F) 13, thereby When the generated lateral force (F ″) 21 is reduced, it is advantageous in terms of vehicle stability. Further, in this case, when there is a sufficient distance from the point where the accelerator is turned off to the entrance 403 of the corner 402, the reference turning vehicle speed Vreq (or the road speed μ taking into consideration the road surface μ) at the time of entering the corner 402 The deceleration force (F) 13 for decelerating to) does not have to be so large, but when the distance to the entrance 403 of the corner 402 is small, the reference turning speed that takes into account the target turning vehicle speed Vreq (or road surface μ) It is necessary to increase the deceleration force (F) 13 for decelerating up to (3). In this case, if the deceleration force (F) 13 is large enough to exceed the tire friction circle, it is disadvantageous in terms of vehicle stability. . In the present embodiment, the deceleration force (F) 13, the limit lateral force (F ′) 19 and the generated lateral force (F ″) 21 for a certain shift speed are obtained by calculation. The optimum gear position is selected in terms of performance.

  Further, according to the present embodiment, when cornering is being performed (step S60-Y), or when non-cornering is being performed (running on a straight road) and there is tire slip (step S140-Y). Until the corner is escaped (step S80-Y), a new upshift and downshift are restricted (step S90), and an incomplete shift (downshift) is canceled so that the shift command is canceled. The hydraulic pressure of the clutch is reduced (step S70). If cornering is in progress, an increase in vehicle deceleration may impair vehicle stability, so an unfinished downshift command is canceled. Also, when there is tire slip on a straight road, an unfinished downshift command is canceled for the same reason.

(First modification of the first embodiment)
Next, a first modification of the first embodiment will be described.
In this modification, the description of parts common to the first embodiment is omitted.

  In the first embodiment, the temporary gear position in step S41 is determined based on the required deceleration 401. In the present modification, for example, a preset map is referred to as shown in FIG. , Based on the road slope and the size of the corner 402 ahead of the vehicle. According to the map, for example, when the road gradient is a gentle downhill and the corner 402 is a gentle corner, the provisional shift stage is determined to be the fourth speed. A plurality of maps shown in FIG. 9 can be prepared for each distance to the corner and for each vehicle speed.

(Second modification of the first embodiment)
Next, a second modification of the first embodiment will be described.
In this modification, the description of parts common to the first embodiment is omitted.

  In the second modification, the shift restriction command (step S70) is output only when the road surface μ detection / estimation unit 92 determines that the road is a low μ road. As described above, if the gear shift command is canceled during the inertia phase or after the gear shift is finished, the feeling of deceleration is lost, and the engine speed also changes from increasing to decreasing, which may cause discomfort. For this reason, the shift command is canceled during the inertia phase or after the end of the shift only when the vehicle stability is to be emphasized.

(Third Modification of First Embodiment)
Next, a third modification of the first embodiment will be described with reference to FIG.
The present modification relates to a vehicle deceleration control device that performs cooperative control of a brake (braking device) and an automatic transmission. In this modification, the description of parts common to the first embodiment is omitted.

  In the first embodiment, the deceleration control is performed using only the deceleration due to the downshift of the transmission. In the present modification, the deceleration control is performed by the cooperative control of the brake and the automatic transmission.

  FIG. 10 is a diagram showing a schematic configuration of the present modification. In FIG. 10, the same components as those in FIG. 2 are given the same reference numerals, and detailed descriptions thereof are omitted.

  A brake braking force signal line L 1 to the brake control circuit 230 is connected to the output port 135 of the control circuit 130. A brake braking force signal SG1 is transmitted through the brake braking force signal line L1.

  The brake device 200 is controlled by a brake control circuit 230 that receives a brake braking force signal SG1 from the control circuit 130, and brakes the vehicle. The brake device 200 includes a hydraulic control circuit 220 and braking devices 208, 209, 210, and 211 provided on the wheels 204, 205, 206, and 207 of the vehicle, respectively. Each of the braking devices 208, 209, 210, and 211 controls the braking force of the corresponding wheels 204, 205, 206, and 207 when the hydraulic pressure is controlled by the hydraulic control circuit 220. The hydraulic control circuit 220 is controlled by the brake control circuit 230.

  The hydraulic control circuit 220 performs brake control by controlling the braking hydraulic pressure supplied to each braking device 208, 209, 210, 211 based on the brake control signal SG2. The brake control signal SG2 is generated by the brake control circuit 230 based on the brake braking force signal SG1. The brake braking force signal SG1 is output from the control circuit 130 of the automatic transmission 10 and input to the brake control circuit 230. The brake force applied to the vehicle during the brake control is determined by a brake control signal SG2 generated by the brake control circuit 230 based on various data included in the brake braking force signal SG1.

  The brake control circuit 230 is configured by a known microcomputer and includes a CPU 231, a RAM 232, a ROM 233, an input port 234, an output port 235, and a common bus 236. A hydraulic control circuit 220 is connected to the output port 235. The ROM 233 stores an operation for generating the brake control signal SG2 based on various data included in the brake braking force signal SG1. The brake control circuit 230 controls the brake device 200 (brake control) based on each input control condition.

  In the present embodiment, not only the shift control of the automatic transmission 10 but also the feedback control of the brake device 200 is executed by the brake control circuit 230. The brake feedback control means that the braking force is controlled according to the deviation between the target deceleration and the actual vehicle deceleration.

  The brake feedback control is started at the location (point a in FIG. 7) where the downshift command is output. That is, a signal indicating the target deceleration is output from the control circuit 130 to the brake control circuit 230 via the brake braking force signal line L1 as the brake braking force signal SG1. The brake control circuit 230 generates a brake control signal SG2 based on the brake braking force signal SG1 input from the control circuit 130, and outputs the brake control signal SG2 to the hydraulic control circuit 220.

  The hydraulic control circuit 220 controls the hydraulic pressure supplied to the braking devices 208, 209, 210, and 211 based on the brake control signal SG2, thereby generating a braking force as instructed in the brake control signal SG2.

  In the feedback control of the brake device 200, the target value is the target deceleration, the control amount is the actual deceleration of the vehicle, the control target is the brake (braking devices 208, 209, 210, 211), and the operation amount is the brake The disturbance is mainly a deceleration due to the shift of the automatic transmission 10. The actual deceleration of the vehicle is detected by the acceleration sensor 90 or the like.

  That is, in the brake device 200, the brake braking force (brake control amount) is controlled so that the actual deceleration of the vehicle becomes the target deceleration. That is, the brake control amount is set so as to cause a deceleration that is insufficient for the deceleration due to the shift of the automatic transmission 10 when the target deceleration is generated in the vehicle.

  In the above, the target deceleration is determined through steps corresponding to steps S41 to S46 in FIG. That is, first, the necessary deceleration 401 is obtained as the temporary target deceleration, and the temporary shift speed is obtained based on the temporary target deceleration (corresponding to step S41), and then the future vehicle speed 11 and the deceleration force (F ) 13 is estimated (corresponding to step S42), and then the lateral lateral force (F ') 19 is estimated from the deceleration force (F) 13 and the traveling environment 18 (corresponding to step S43), and the destination road shape 23 and the vehicle speed 11 are estimated. The generated lateral force (F ″) 21 is estimated from the above (corresponding to step S44), and the target deceleration is determined in a range where the generated lateral force (F ″) 21 does not become larger than the limit lateral force (F ′) 19. Based on the target deceleration (corresponding to step S45), the gear position is determined (corresponding to step S46).

  In the above, the target deceleration requires that the deceleration force (F) 13 corresponding to the elapsed time from when the downshift command (the brake control command is also output) is output is known in advance. .

  Note that the brake control in the present embodiment may be performed by using a braking device that generates a braking force on the vehicle, such as a regenerative braking by an MG device provided in the power train system, instead of the brake.

(Fourth modification of the first embodiment)
In the first embodiment, the corner control is described as being performed by controlling the gear position of the stepped automatic transmission 10, but instead, the control of the gear ratio of the CVT can be performed.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG.
In the second embodiment, description of parts common to the first embodiment is omitted, and only characteristic parts will be described.

  In the second embodiment, the shift speed is determined by a method different from the shift speed determination method (steps S42 to S45) in the first embodiment (step SA41, step S46). In the first embodiment, the vehicle speed 11, the deceleration force (F) 13, the limit lateral force (F ′) 19, and the generated lateral force (F ″) 21 are changed every time a predetermined time (Δt) elapses. You are asked to be updated. On the other hand, in the present embodiment, the optimum gear position is determined by a simpler method.

  FIG. 11 is a flowchart for explaining operations unique to the second embodiment, and only the differences from the flowchart of FIG. 1 are described.

[Step SA41]
As shown in FIG. 11, when it is determined that corner control is necessary (step S30-Y), in step SA41, it is assumed that deceleration control with the destination gear stage being N stage is performed. Vehicle stability is estimated.

  Specifically, at the point where the accelerator is turned off (point a in FIG. 7), the vehicle speed at the entrance 403 of the corner 402 (corner approaching vehicle speed) when it is assumed that the deceleration control is performed at the N shift stage. The speed is estimated based on the shift speed (N speed) and the current vehicle speed. Based on the corner approaching vehicle speed and the corner R405 of the corner 402, the generated lateral force (F ") 21 that will be generated during the turn is estimated.

  When the generated lateral force (F ″) 21 is larger than a predetermined turning G during corner turning which is set in advance, it is determined that the vehicle becomes unstable. When the generated lateral force (F ″) 21 obtained by the above method is equal to or less than the desired turning G, the gear stage (N stage) is determined as the downshift destination gear stage (step S46). In this case, corner control is not performed when there is no shift speed (N speed) at which the generated lateral force (F ″) 21 is equal to or less than the desired turning G.

  In the first embodiment, in order to determine the limit lateral force (F ′) 19 from the tire friction circle (running environment 18) and the deceleration force (F) 13 (step S43), the running stability of the vehicle is estimated. The deceleration force (F) 13 was used. On the other hand, in this embodiment, as described below, the running stability of the vehicle is estimated by a simple method without using the deceleration force (F) 13.

  The difference in the deceleration force (F) 13 at the entrance 403 of the corner 402 due to the shift speed is not so large. At any shift stage, a certain degree of deceleration is performed up to the entrance 403 of the corner 402, and the deceleration force (F) 13 at the entrance 403 of the corner 402 is reduced regardless of the shift stage. The difference of the deceleration force (F) 13 at the entrance 403 of the corner 402 due to is reduced.

  On the other hand, the difference in the deceleration force (F) 13 depending on the shift stage has a great influence on the corner approaching vehicle speed (the integrated value of the deceleration force (F) 13 affects the vehicle speed). The difference in the deceleration force (F) 13 depending on the shift speed is represented by the corner approaching vehicle speed. Based on this, in this embodiment, the value of the deceleration force (F) 13 is not used, and the running stability of the vehicle is estimated based only on the corner approaching vehicle speed and the corner R405 of the corner 402.

(Third embodiment)
Next, a third embodiment will be described with reference to FIG.
In the third embodiment, description of parts common to the above embodiment is omitted, and only characteristic parts are described.

  In this embodiment, the vehicle speed at the time of entering the corner is estimated based on the vehicle speed and the deceleration at each shift stage, and the estimated vehicle speed and the reference vehicle speed determined by the corner R405 of the corner 402 and the road surface μ are obtained. Based on the comparison result, the necessity of the deceleration control and the restriction gear position at the time of the deceleration control are determined.

  In the first embodiment, the generated lateral force (F ″) 21 with respect to the limit lateral force (F ′) 19 determined from the tire friction circle (running environment 18) and the deceleration force (F) 13 in FIG. The running stability of the vehicle has been determined based on the magnitude relationship.

  On the other hand, in the present embodiment, the running stability of the vehicle is ensured (the road surface μ is taken into consideration and the vehicle can turn below the desired turn G). It is assumed that the corner 402 is turned after the vehicle is decelerated to the required reference vehicle speed at the corner 402 entry point (point b in FIG. 7) corresponding to the corner R405. Therefore, in this embodiment, the magnitude of the generated lateral force (F ″) 21 is not a problem.

  That is, in the present embodiment, the optimum speed for decelerating to the reference vehicle speed up to the entry point of the corner 402 based on the vehicle speed at the current position (point where the accelerator is turned off) and the deceleration at each gear position. The gear position is determined. In this case, among the gears that can be decelerated to the reference vehicle speed before the entry point of the corner 402, the gear that does not exceed the tire friction circle is determined as the optimum gear that does not exceed the tire friction circle. Is done. In this case, there is theoretically a gear stage that can be decelerated to the reference vehicle speed by the entry point of the corner 402, but the deceleration force (F) 13 by the gear stage is the tire friction circle for any of the gear stages. If it exceeds, the optimum gear position is not determined and downshift control is not performed.

  FIG. 12 is a map prepared in advance for determining the optimum gear position based on the above-described criterion that the gear position can be decelerated to the reference vehicle speed before the corner 402 enters. A plurality of maps in FIG. 12 can be prepared for each value of the road surface μ. In the map, the regulated shift speed is determined based on the corner R405 of the corner 402 and the vehicle speed at the current position. Here, the magnitude of the vehicle speed at the current position is the magnitude of the vehicle speed that should be reduced from the vehicle speed at the current position to the reference vehicle speed from the entry point of the corner 402, in other words, from the vehicle speed at the current position. It corresponds to the value obtained by subtracting the vehicle speed. The optimum gear (corresponding to the gear determined in step S46) is a gear that is one gear lower (for low speed) than the regulated gear.

In the map of FIG. 12, the corner R405 of the corner 402 is divided into four stages of a straight line, a gentle corner, a middle corner, and a hairpin, and the vehicle speed at the current position is V ₁ or less, V _{1 to} V ₂ , V _{2 to} V. ₃ and divided into 4 stages of V ₃ or more.

For example, if the vehicle speed at the current position is less than or equal to V ₁ at a gentle corner, it is determined that corner control is not necessary. In this case, it is determined that the corner 402 can be safely turned even if corner control is not performed. When the vehicle speed at the current position is V _{1 to} V ₂ , the restriction gear stage is set to the fifth speed, and the optimum gear stage is set to the fourth speed. When the vehicle speed at the current position is V _{2 to} V ₃ , the restriction gear stage is set to the fourth speed, and the optimum gear stage is set to the third speed. When the vehicle speed at the current position is V ₃ or more, the deceleration force (F) 13 for decelerating to the reference vehicle speed exceeds the tire friction circle, so corner control is not executed.

  In the above description, the deceleration indicating the amount that the vehicle should decelerate has been described using the deceleration acceleration (G), but it is also possible to control based on the deceleration torque.

From the above embodiments, the following items are disclosed.
In the description of each item below, the configuration in parentheses [] is not an essential requirement.

(Claim 1)
A vehicle deceleration control device that changes at least the gear position of an automatic transmission when a driver's intention to decelerate is detected with respect to a front corner, wherein the speed at the front road, the vehicle speed, and the deceleration at each gear stage Based on the estimated vehicle speed and the estimated deceleration, the stable limit turning state is estimated, and the turning state and the turning state of the limit turning state are estimated. A vehicle deceleration control device that determines whether or not deceleration control is necessary and a restriction gear position during deceleration control based on a comparison result.

(Section 2)
In the vehicle deceleration control apparatus according to Item 1, the driving environment includes a road surface friction coefficient, or a TRC (traction control system) capable of estimating a road surface friction coefficient, and an ABS (anti-lock brake system) operating state. A vehicle deceleration control device including an outside air temperature and a rainfall amount.

(Section 3)
The vehicle deceleration control device according to Item 1, wherein the corner entrance (a point / time point at which a predetermined turning degree is reached) is set in front (early) in consideration of the position detection accuracy of the navigation system device. Deceleration control device.

(Claim 4)
In the vehicle deceleration control device according to Item 1, an amount for setting a corner entrance (a point / time point at which a predetermined turning degree is reached) to the front (early) is determined based on the position detection accuracy of the navigation system device. A vehicle deceleration control device.

(Section 5)
A vehicle deceleration control device that changes at least the gear position of an automatic transmission when a driver's intention to decelerate is detected with respect to a preceding corner, depending on the vehicle speed and the deceleration at each gear stage. The vehicle speed at the time of entering the corner is estimated, and the necessity of deceleration control and the regulation at the time of deceleration control are based on the comparison result between the estimated vehicle speed and the reference vehicle speed determined by the road shape [and the driving environment] A vehicle deceleration control apparatus characterized by determining a gear position.

It is a flowchart which shows operation | movement of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a schematic block diagram of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a flowchart which shows other operation | movement of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a figure for demonstrating operation | movement of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a block diagram for demonstrating other operation | movement of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a block diagram for demonstrating other operation | movement of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a chart for demonstrating operation | movement of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. In the first embodiment of the vehicle deceleration control device of the present invention, it is a diagram showing the deceleration for each vehicle speed of each gear stage. 5 is a gear map that can be used in a modification of the first embodiment of the vehicle deceleration control device of the present invention. It is a schematic block diagram of the modification of 1st Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a flowchart which shows operation | movement of 2nd Embodiment of the deceleration control apparatus of the vehicle of this invention. It is a map used in 3rd Embodiment of the deceleration control apparatus of the vehicle of this invention.

Explanation of symbols

10 automatic transmission 11 vehicle speed 12 shift stage 13 deceleration force (F)
14 Driving resistance 15 Vehicle deceleration (α)
17 ΔL
18 Driving environment 19 Limit lateral force (F ')
21 Generated lateral force (F ″)
23 road shape 31 resultant force 40 engine 90 acceleration sensor 91 tire slip determination unit 92 road surface μ detection / estimation unit 95 navigation system device 114 throttle opening sensor 116 engine speed sensor 118 road gradient measurement / estimation unit 122 vehicle speed sensor 123 shift position Sensor 130 Control circuit 131 CPU
133 ROM
200 Brake device 230 Brake control circuit 401 Required deceleration 402 Corner 403 Corner inlet 404 Corner outlet 405 Corner R
a Accelerator off point b Point offset from the corner entrance Vreq Target turning vehicle speed L1 Brake braking force signal line Lc Control execution boundary line SG1 Brake braking force signal SG2 Brake control signal

Claims (3)

A vehicle deceleration control device that performs deceleration control by shifting a transmission based on the shape of a corner at the front of the vehicle,
A generated lateral force estimating means for estimating a lateral force generated in the vehicle turning the corner based on the shape and vehicle speed of the corner;
Threshold value estimation means for estimating a threshold value related to a turning state of the vehicle for the vehicle to stably turn the corner based on the vehicle speed and a deceleration by a gear stage or a gear ratio of the transmission; ,
Based on the estimated lateral force generated in the vehicle and the estimated threshold, whether or not the deceleration control is necessary, and the shift stage or shift of the transmission destination of the transmission when the deceleration control is performed Means for determining the ratio, and
The determining means is a gear stage or a gear ratio at which a lateral force generated in the estimated vehicle is equal to or less than the estimated threshold when the deceleration control is performed, and the corner is in the turning state . The gear stage or gear ratio that is the closest to the required deceleration for turning is selected as the temporary gear stage or the temporary gear ratio, and the higher gear stage or the higher gear stage than the temporary gear stage or the temporary gear ratio is selected . A deceleration control apparatus for a vehicle, characterized in that a gear stage or a gear ratio which is a gear ratio and has a maximum gear shift amount is determined as a gear stage or gear ratio of a destination of the transmission. The vehicle deceleration control device according to claim 1 ,
The threshold value estimation means further estimates the threshold value based on the ease of slipping of the road surface of the corner. The vehicle deceleration control device according to claim 1 or 2 ,
The vehicle deceleration control device, wherein the turning state estimation means changes an estimation result of the turning state of the vehicle based on position detection accuracy of the navigation system device of the vehicle.

Images