JP4075585B2 - Vehicle speed control device and program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a technique for stably passing a road curve or the like by predicting and controlling a stable traveling speed of a vehicle.
[0002]
[Prior art]
Conventionally, as a technique for reducing a driver's operation burden, for example, in a situation in which the vehicle speed is desired to be kept constant, such as on a highway, a vehicle is driven with a vehicle speed set by the driver maintained. A vehicle speed control device that performs high-speed running control is known. Here, the constant speed running control is control for running the vehicle while maintaining the set vehicle speed by controlling acceleration means and deceleration means for accelerating / decelerating the vehicle.
[0003]
Various proposals have been made to make traveling by such a vehicle speed control device safer. For example, when traveling on a curve, there is one that controls the vehicle speed so as to decelerate to a vehicle speed at which the vehicle can pass through the curve in a stable state (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-96654 (page 4, FIGS. 2, 3 and 4)
[0005]
[Problems to be solved by the invention]
However, when the vehicle speed control as described above is executed, as illustrated in FIG. 11, the vehicle speed until the vehicle can pass through in a stable state before the curve (corresponding to the “curve entrance” in FIG. 11). It may slow down.
[0006]
On the other hand, a general driver controls the vehicle speed as follows when the vehicle approaches a curve. That is, as illustrated in FIG. 2, the driver can safely make the curve in consideration of available information such as the shape of the curve, the current speed of the vehicle, the road surface condition, the condition of the vehicle / curve, and the performance of the vehicle. It quickly predicts the speed of the vehicle to travel and the trajectory of travel, predicts the deceleration required to enter the curve, and operates the brake to decelerate. When a vehicle enters a curve, the driver predicts the vehicle's speed to safely drive the curve peak where the curve is most tight, and the deceleration required to reach that curve peak. And continue running while adjusting the deceleration condition as appropriate by operating the brake. When the vehicle passes the curve peak, the driver waits to reach the curve exit while maintaining the vehicle speed, and the legal speed of the road and the speed that the driver considers safe when driving on the next straight road Accelerate the vehicle until.
[0007]
As described above, the vehicle speed control performed by the conventional vehicle speed control device may be different from the vehicle speed control performed by a general driver, which may make the driver feel uncomfortable. In addition, when there is a following vehicle, if the vehicle speed control device decelerates to a vehicle speed that allows the vehicle to pass in a stable state before the curve as described above, the following vehicle may be too close to the vehicle. is there.
[0008]
The present invention has been made in view of such problems, and an object of the present invention is to realize vehicle speed control that does not give the driver a sense of incongruity.
[0009]
[Means for Solving the Problems and Effects of the Invention]
According to the vehicle speed control device according to claim 1, which has been made to solve the above-mentioned problems, the position detection means (5: In this section, in order to facilitate understanding of the invention, the embodiment is provided as necessary. ) Is used to detect the position of the host vehicle, and the vehicle speed detecting means (16) detects the current speed of the host vehicle. To do. Subsequently, the scheduled passage node detection means (5) detects one or more nodes that the vehicle is scheduled to pass based on the position of the vehicle and the map information in the map information storage means (5). Furthermore, the stable travel speed calculation means (2) calculates a stable travel speed that is a vehicle speed for traveling stably when the vehicle passes through the scheduled passage node. As for the stable travel speed, instead of calculating the stable travel speed for each node that the vehicle is scheduled to pass through as described above, the stable travel speed calculated in advance for each node on the map is used as the map information storage means. You may make it memorize | store and use it. Then, based on the vehicle position, the scheduled passage node, the stable traveling speed at the scheduled passage node, and the current speed of the vehicle, the deceleration calculation means (2) determines the current vehicle speed until the vehicle reaches the scheduled passage node. A deceleration for decelerating from the speed to the stable traveling speed at the node scheduled to pass is calculated. Then, the deceleration target point setting means (2) selects the maximum deceleration node that has the largest deceleration among the scheduled passage nodes based on the deceleration calculated by the deceleration calculation means, and the maximum deceleration A maximum deceleration node is set at the primary deceleration target point, which is the target point for the first deceleration control after the node is selected, and the stable traveling speed is farther than the maximum deceleration node among the planned passing nodes. Select the deceleration end node that reverses from decrease to increase, and set the deceleration end node to the secondary deceleration target point that is the target point for the second deceleration control after selecting the maximum deceleration node . Then, the control means (2) controls the speed of the vehicle so as to reach the stable traveling speed at the maximum deceleration node until the primary deceleration target point is reached by controlling the deceleration means (4), and further the primary deceleration. When the target point and the secondary deceleration target point are different, the speed of the vehicle is controlled so as to reach the stable traveling speed at the deceleration end node by controlling the deceleration means and reaching the secondary deceleration target point. When the control means controls the vehicle speed toward the primary deceleration target point or the secondary deceleration target point in this way, the vehicle may be decelerated at a constant deceleration. You may make it decelerate in steps.
[0010]
Thus, the vehicle speed control executed by the vehicle speed control device is performed by a general driver as illustrated in FIG. 2 as compared with the conventional vehicle speed control in which only the curve entrance as illustrated in FIG. 11 is a deceleration target. It approaches the deceleration control that matches the curve shape, that is, the stepwise deceleration control with the entrance of the curve and the curve peak as the deceleration target. Furthermore, when there is a following vehicle, it is safer because the following vehicle can easily predict the behavior of the vehicle. Therefore, vehicle speed control that does not give the driver a sense of incongruity can be realized.
[0011]
After passing the secondary deceleration target point, the vehicle speed may be controlled so that the vehicle speed is maintained until the vehicle passes the curve. Further, by providing acceleration means, the vehicle speed may be controlled so as to accelerate after maintaining the vehicle speed for a while. In this case, as a point where acceleration is started, as illustrated in FIG. 7, a vehicle speed obtained by multiplying a stable traveling speed at the secondary deceleration target point by a coefficient (for example, a numerical value greater than 1 such as a numerical value 1.2) (FIG. 7). Corrected acceleration target vehicle speed V_{twenty one}) (Corresponding to the acceleration start point after the curve in FIG. 7).
[0012]
  By the way, when controlling the speed of the vehicle based on the stable traveling speed at each node, if the vehicle starts decelerating from a distance more than necessary, the vehicle slowly decelerates, which makes the passenger of the vehicle feel uncomfortable. . Therefore, SystemIt is conceivable that the control means does not start the deceleration control when the deceleration at the maximum deceleration node is less than a preset value.
[0013]
Here, “value set in advance (reference deceleration α of the embodiment₀Is equivalent to the maximum value at which the driver of the vehicle, such as the driver, does not feel uncomfortable when the vehicle is decelerated at the deceleration of that value. . In this way, since it is no longer necessary to start decelerating from far away, it is possible for the vehicle occupant to drive without feeling uncomfortable.
[0014]
By the way, it is conceivable that the above-described passing point node is detected based on the following criteria. That is, (a) It is conceivable to select from the map information a node that exists within a certain range from the current vehicle position, such as a distance from the vehicle position of 500 m, for example. (B) When the vehicle decelerates at the reference deceleration, it is conceivable to select a node existing from the current vehicle position to the stop point from the map information.
[0015]
  In addition, since the nodes of the map information are set at intervals, the point where the deceleration is actually the largest may be located between the nodes and may not match the maximum deceleration node. Among them, if the point where the actual deceleration becomes the largest is closer to the front than the maximum deceleration node, there is a possibility that sufficient deceleration will not be performed before reaching the point where the actual deceleration becomes the largest. . Therefore, the claim1As described above, it is conceivable that the deceleration target point setting means resets the primary deceleration target point before the maximum deceleration node. Here, as a specific example of the reset position of the primary deceleration target point, as illustrated in FIG. 5, the value of the vehicle speed is a coefficient (for example, a numerical value of 1.2 or the like) to the stable traveling speed at the maximum deceleration node. It is conceivable that the above-described primary deceleration target point is reset to a point (corresponding to the primary deceleration target point in FIG. 5) that is a value obtained by multiplying by a value greater than 1). In this way, there is an increased possibility of sufficient deceleration before reaching a point where the actual deceleration becomes the largest.
[0016]
  Also, in the case of the deceleration end node, as in the case of the maximum deceleration node described above, the point where the deceleration should actually end may not match the deceleration end node. Therefore, the claim2As described above, it is conceivable that the deceleration target point setting means resets the secondary deceleration target point before the deceleration end node. In this way, the possibility of sufficient deceleration before reaching the point where deceleration actually ends is increased.
[0017]
  By the way, for example, when the vehicle is accelerating when executing deceleration control such as a curve ahead, the acceleration is temporarily stopped and then the deceleration is started. Then, because it was accelerating, the start of deceleration was delayed compared to when it was running at a constant speed, and accordingly, a large deceleration was required before reaching the primary deceleration target point or secondary deceleration target point. Will be uncomfortable. Therefore, the claim3In this way, the deceleration target point setting means sets the primary deceleration target point and the secondary deceleration target point to the near side for the travel distance until the acceleration that is longer than when traveling at a constant speed is completed. You should try again. In this way, even if the vehicle is accelerating, the driver does not feel uncomfortable before reaching the primary deceleration target point and the secondary deceleration target point (if different from the primary deceleration target point). Sufficient deceleration can be performed.
[0018]
  Furthermore, during execution of deceleration control, the vehicle may decelerate more than expected due to traffic jams. Therefore, the claim4In this way, when the speed of the vehicle reaches the stable traveling speed at the maximum deceleration node on the near side of the primary deceleration target point, the acceleration control means for accelerating the vehicle is provided. On the other hand, when the vehicle speed is lower than the stable traveling speed at the maximum deceleration node on the near side of the primary deceleration target point, the vehicle is accelerated by controlling the acceleration means. Can be considered. In this way, vehicle speed control that does not give the driver a sense of incongruity can be realized.
[0019]
  Claims5In the case where the acceleration means for accelerating the vehicle is provided, and the control means reaches the stable traveling speed at the deceleration end node between the primary deceleration target point and the acceleration start point, When deceleration control is stopped and the vehicle is in a constant speed running state, while the vehicle speed is lower than the stable running speed at the deceleration end node between the primary deceleration target point and the acceleration start point. It is conceivable to control the acceleration of the vehicle by controlling the acceleration means. Here, the “acceleration start point” is a point at which the vehicle starts to accelerate (“acceleration start point after curve corresponds to FIG. 8, refer to the embodiment).” This makes the driver feel uncomfortable. Vehicle speed control can be realized.
[0020]
  by the way1You may comprise so that a driver | operator can change at least any one of the value of the stable traveling speed in a next deceleration target point, or the value of the stable traveling speed in a secondary deceleration target point. As an example, it can be considered to multiply the value of the stable traveling speed at each point by a coefficient and reset the value. It should be noted that the coefficient value in this case is set to a value larger than 1 such as the numerical value 1.2 when it is desired to increase the vehicle speed as a whole, while this coefficient is set to a value that is lower than the vehicle speed as a whole. May be set to a value less than 1 such as 0.8. In this way, the driver can correct the vehicle speed control to his / her preference, so that it is possible to realize vehicle speed control that does not make the driver feel uncomfortable. In this case, the setting of the coefficient described above may be configured such that the driver inputs a numerical value, or the option set by the manufacturer to reflect the driving preference of the driver (for example, a numerical value of 0.8, The driver may select from 1.0, 1.2, etc.). In addition, instead of presenting the numerical values of the coefficients, it is desirable that the names of the soft mode, the normal mode, the sports mode, and the like are given in order from the smallest coefficient values so that the driver can easily understand. In addition, the setting of the above-described coefficient options may be set in advance when manufacturing the vehicle speed control device of the present invention, and if the setting can be changed later, the driver sets it. Also good.
[0021]
  Claims6As shown, the deceleration calculation means, the deceleration target point setting means, the control means, and the stable travel speed calculation means in the vehicle speed control device can be realized as a program that causes a computer to function. Therefore, the present invention can be realized as a program invention. In the case of such a program, for example, the program is recorded on a computer-readable recording medium such as an FD, MO, DVD-ROM, CD-ROM, or hard disk, and is used by being loaded into a computer and started up as necessary. be able to. In addition, the ROM or backup RAM may be recorded as a computer-readable recording medium, and the ROM or backup RAM may be incorporated into the computer for use.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments to which the present invention is applied will be described below with reference to the drawings. Needless to say, the embodiments of the present invention are not limited to the following examples, and can take various forms as long as they belong to the technical scope of the present invention.
[0023]
FIG. 1 is a block diagram schematically showing a system configuration of a cruise control apparatus to which the above-described invention is applied, an inter-vehicle control electronic control device (hereinafter referred to as “inter-vehicle control ECU”) 2, an engine control. An electronic control device (hereinafter referred to as “engine ECU”) 6 and a brake electronic control device (hereinafter referred to as “brake ECU”) 4 are mainly configured.
[0024]
[Description of configuration of inter-vehicle control ECU 2 and the like]
The inter-vehicle control ECU 2 is an electronic circuit mainly composed of a microcomputer, and controls the current vehicle speed (Vn) signal, steering angle signal, yaw rate signal, target inter-vehicle time signal, wiper switch information, idle control and brake control. A signal or the like is received from the engine ECU 6. The inter-vehicle control ECU 2 also receives travel route information from the navigation device 5 described later. Further, based on the received data, the inter-vehicle control ECU 2 estimates the curve curvature radius R, calculates the inter-vehicle control, and a speed for stably driving the vehicle at each node described later (hereinafter referred to as a stable travel speed). )), Calculation of deceleration at each node described later, setting of a deceleration target point described later, vehicle speed control, and the like. The inter-vehicle control ECU 2 corresponds to a stable travel speed calculation means, a deceleration calculation means, a deceleration target point setting means, and a control means.
[0025]
The laser radar sensor 3 is an electronic circuit mainly composed of a laser scanning range finder and a microcomputer. The angle and relative speed of the preceding vehicle detected by the scanning range finder and the inter-vehicle distance control ECU 2 Based on the received current vehicle speed (Vn) signal, curve curvature radius R, etc., the vehicle lane probability of the preceding vehicle is calculated as a part of the function of the inter-vehicle control device, and the preceding vehicle information including information such as relative speed is It transmits to control ECU2. The diagnostic signal of the laser radar sensor 3 itself is also transmitted to the inter-vehicle control ECU 2.
[0026]
The scanning distance measuring device scans and radiates a transmission wave or laser light within a predetermined angle range in the vehicle width direction, and based on the reflected wave or reflected light from the object, the distance between the vehicle and the front object is a scan angle. It functions as a distance measuring means that can be detected corresponding to
[0027]
Further, the inter-vehicle control ECU 2 determines a preceding vehicle to be subjected to the inter-vehicle distance control based on the own lane probability included in the preceding vehicle information received from the laser radar sensor 3, and appropriately adjusts the inter-vehicle distance with the preceding vehicle. As a control command value, a target acceleration / deceleration signal, a fuel cut request signal, an OD cut request signal, a third speed shift down request signal, and a brake request signal are transmitted to the engine ECU 6. Further, it determines whether an alarm has occurred and transmits an alarm sound request signal or transmits an alarm sound release request signal. Further, a diagnosis signal, a display data signal, and the like are transmitted.
[0028]
[Description of Configuration of Navigation Device 5]
The navigation device 5 is mainly composed of a navigation ECU, a GPS (global positioning system) sensor as a position detection means, a DVD-ROM as a map information storage means for recording a map database, and the like. It calculates and outputs information on the travel route on which the host vehicle is traveling to the inter-vehicle control ECU 2 at regular intervals (about every second in this embodiment).
[0029]
Here, as the information regarding the traveling road, there are link information, node information, segment information, inter-link connection information, and the like, which are stored in the road database.
The link information includes a “link ID” that is a unique number for identifying a link, a “link class” for identifying an expressway, a toll road, a general road, an attachment road, and the like, There is information about the link itself such as “coordinates” and “end coordinates” and “link length” indicating the length of the link.
[0030]
The node information includes “node ID” that is a unique number of nodes connecting the links, node latitude, node longitude, right / left turn prohibition at intersections, presence / absence of traffic lights, and the like. The segment information includes information such as segment ID, start point (node) latitude (degrees), start point (node) longitude (degrees), segment direction (dir), and segment length (internode distance, len). is there. Note that the values of the starting point latitude and starting point longitude include decimal places and are converted from “minutes” and “seconds” to “degrees”. Further, the direction of the segment (dir) is set to be counterclockwise with the true east direction on the map as a reference (dir = 0), and one unit (dir = 1) is divided into 360 degrees by 1024 divisions. . For example, “dir = 30” represents a direction rotated counterclockwise (30 × 360/1024) degrees from the true east direction on the map. In addition, as for the length of the segment (distance between nodes, len), one unit (len = 1) is set to the actual 10 cm.
[0031]
In the link connection information, for example, data indicating whether or not traffic is allowed for one-way traffic is set. Even in the case of the same link, for example, in the case of one-way traffic, it is possible to pass from one link but not from another link. Therefore, whether or not traffic is allowed is determined depending on the connection mode between the links.
[0032]
The navigation device 5 corresponds to a scheduled node detection unit.
[Description of configuration of brake ECU 4]
The brake ECU 4 is an electronic circuit mainly composed of a microcomputer. The brake ECU 4 obtains the steering angle and the yaw rate from the steering sensor 8 for detecting the steering angle of the vehicle and the yaw rate sensor 10 for detecting the yaw rate. The brake actuator 25 that controls transmission / opening of the pressure increase control valve / pressure reduction control valve provided in the brake hydraulic circuit to control the braking force is transmitted to the inter-vehicle control ECU 2 via the ECU 6. The brake ECU 4 sounds the alarm buzzer 14 in response to an alarm request signal from the inter-vehicle control ECU 2 via the engine ECU 6. The brake ECU 4 corresponds to a deceleration means.
[0033]
[Description of Configuration of Engine ECU 6]
The engine ECU 6 is an electronic circuit mainly composed of a microcomputer, and includes a throttle opening sensor 15, a vehicle speed sensor 16 as vehicle speed detection means for detecting vehicle speed, a brake switch 18 for detecting whether or not the brake is depressed, and cruise. Detection signals from the control switch 20, the cruise main switch 22, and other sensors and switches, or wiper switch information and tail switch information received via a known communication line such as the body LAN 28 are received. Further, a steering angle signal and a yaw rate signal from the brake ECU 4, or a target acceleration signal, a fuel cut request signal, an OD cut request signal, a third speed shift down request signal, an alarm request signal, a diagnosis signal, and display data from the inter-vehicle control ECU 2 A signal is received.
[0034]
Here, the cruise control switch 20 includes a control start switch, a control end switch, an accelerator switch, a coast switch, and the like. The control start switch is a switch for making cruise control startable, and the cruise control can be started by turning on the control start switch while the main switch is ON. In this cruise control, the inter-vehicle control and the constant speed traveling control are selectively executed under predetermined conditions. The accelerator switch is a switch for gradually increasing the stored set vehicle speed by pressing the accelerator switch. The coast switch gradually decreases the stored set vehicle speed by pressing the accelerator switch. It is a switch for. Further, the inter-vehicle distance between the host vehicle and the preceding vehicle can be set via the cruise control switch 20. The inter-vehicle distance can be set in stages according to the driver's preference.
[0035]
Then, the engine ECU 6 drives the throttle actuator 24 for adjusting the throttle opening degree of the internal combustion engine (here, the gasoline engine) and the actuator drive means of the transmission 26 according to the operating state determined from the received signal. Is output. With these actuators, it is possible to control the output, braking force or shift shift of the internal combustion engine. The transmission 26 in the present embodiment is a 5-speed automatic transmission, the 4-speed reduction ratio is set to “1”, and the 5-speed reduction ratio is smaller than the 4-speed (for example, 0.7). The so-called 4-speed + overdrive (OD) configuration is set. Therefore, when the above-described OD cut request signal is issued, if the transmission 26 has been shifted to the fifth speed (that is, the overdrive shift position), it is shifted down to the fourth speed. When a downshift request signal is issued, the transmission 26 is shifted down to the third speed if the transmission 26 is shifted to the fourth speed. As a result, a large engine brake is caused by these downshifts, and the vehicle is decelerated by the engine brake.
[0036]
The engine ECU 6 transmits necessary display information to a display device such as an LCD provided in the meter cluster via the body LAN 28 for display, or displays the current vehicle speed (Vn) signal, steering angle signal, A yaw rate signal, a target inter-vehicle time signal, a wiper switch information signal, a control state signal for idle control and brake control are transmitted to the inter-vehicle control ECU 2.
[0037]
[Explanation of deceleration control processing]
Next, the deceleration control process executed by the above-mentioned inter-vehicle control ECU 2 will be described with reference to the flowchart for explaining the deceleration control process in FIG. 3 and the explanatory diagrams 1 to 7 for the deceleration control in FIGS. 4 to 10, the distance L from the current position of the vehicle is set on the horizontal axis, and the speed of the vehicle (vehicle speed v in the figure) is set on the horizontal axis. Travel speed V_TEtc. are plotted, and the approximate curve connecting these plotted points is represented. In the figure, points relating to deceleration control such as a primary deceleration target point described later are appropriately shown.
[0038]
In the first step 110 (hereinafter, “step” is simply referred to as “S”), the navigation device 5 calculates the vehicle position, the vehicle speed sensor 16 detects the current vehicle speed, and then the vehicle position. To standard deceleration rate α₀Stop distance L to the point to stop when decelerating at₀(M) is calculated using the following equation (1).
[0039]
L₀= V₀ ²/ 2α₀= V₀ ²/(2×0.784) (1)
V₀: Current speed of vehicle (m / s)
α₀: Standard deceleration (m / s²)
Here, “reference deceleration α₀"" Refers to a deceleration that does not cause the driver or other passengers of the vehicle to feel uncomfortable when the vehicle is decelerated at that deceleration, and may be defined in advance by experiments or the like. In this embodiment, 0.08 G (= 0.784 m / s²) Is set. Then, as shown in FIG. 4, the navigation device 5 determines the stop distance L from the position of the vehicle based on the map database.₀The first point, that is, the vehicle is the reference deceleration α from the current position₀When the vehicle decelerates, a node existing until the point where the vehicle stops is detected, and information on the node is output to the inter-vehicle control ECU 2.
[0040]
Next, a stable traveling speed V that is a speed for traveling stably when the vehicle passes through each node._T, And the deceleration α required for accelerating / decelerating to the stable traveling speed at each node until the vehicle reaches each node_nAre calculated in order.
Specifically, first, a segment l connecting a reference node that is one of the detected nodes and a node on the front side of the reference node._n-1And the segment l that connects the reference node and the node on the opposite side of the reference node_nIs calculated by using the following expression (2) or (2 ′).
[0041]
dθ = (dir_n―Dir_n-1) × 360/1024 (2)
dθ = {1024- (dir_n―Dir_n-1)} × 360/1024 (2 ′)
dθ: Segment l_n-1And segment l_nAngle between and (degrees)
dir_n: Segment l_nDirection
dir_n-1: Segment l_n-1Direction
In this case, (dir_n―Dir_n-1) Is less than the numerical value 512, equation (2) is used and (dir_n―Dir_n-1When the absolute value of) is greater than or equal to 512, Equation (2 ′) is used. Also, (dir_n―Dir_n-1) Is a negative value, its absolute value is used in the calculation.
[0042]
Next, the angle dθ is corrected using the following equation (3) for the following reason. That is, a vehicle traveling on a curve travels in a straight line in a portion corresponding to a segment on the road, and does not turn at the angle dθ at each node. This is because the vehicle travels while drawing an arc outside the portion corresponding to. L_nAnd l_n-1Here is the segment l_n, L_n-1Represents the length of. In this case, since the length of each segment on the map database is expressed using len, a value calculated using the calculation formula len × 0.1 (m) is used here.
[0043]
dθ₁= (L_n/ (L_n-1+ L_n)) × dθ (3)
dθ₁: Segment l_n-1And segment l_nCorrected for the angle dθ between and the segment l_n-1The vehicle having passed through the angle dθ described above at the reference node₁The lateral movement distance S (m) required to reach the next node position when traveling straight at is calculated using the following equation (4).
[0044]
S = l_n× sindθ₁... (4)
And the stable traveling speed V which is a vehicle speed for driving | running | working stably when a vehicle passes each node._T(M / s) is calculated for each node using the following equation (5).
V_T= L_n× (N / 2S)^1/2(5)
N: Specified value (m / s²)
The specified value N is 0.3 G (= 2.94 m / s) in this embodiment.²) Is set.
[0045]
Also, the deceleration α required for the vehicle to accelerate and decelerate to the stable traveling speed at each node before reaching each node._n(M / s²) Is calculated for each node using the following equation (6).
α_n= (V₀ ²―V_T ²) / 2L_T... (6)
L_T: Distance from the current position of the vehicle to the node (m)
In subsequent S120, as shown in FIG. 5, the deceleration α of each node calculated in S110._nIs selected as the “primary deceleration target node”, and the stable traveling speed at the primary deceleration target node is set to “primary deceleration target vehicle speed V”.₁" Here, when there are a plurality of candidates for the primary deceleration target node, the node closer to the vehicle is set as the primary deceleration target node. The “primary deceleration target node” corresponds to the maximum deceleration node.
[0046]
In S130, a primary deceleration target point is set. The primary deceleration target point is a target point for the first deceleration control after the node having the largest deceleration value is selected in S120. Specifically, as shown in FIG. 5, the primary deceleration target vehicle speed V₁Is multiplied by “deceleration target speed ratio (numerical value 1.2 in this embodiment)” to obtain a corrected primary deceleration target vehicle speed V₁₁And And the corrected primary deceleration target vehicle speed V in a substantially curved line connecting the nodes.₁₁Is set as the primary deceleration target point. This setting is made for the following reason. In other words, since the nodes of the map information are set at an interval, the point where the deceleration is actually greatest may not coincide with the position on the road corresponding to the primary deceleration target node. is there.
[0047]
In subsequent S140, it is determined whether or not the vehicle is accelerating. If the vehicle is accelerating (S140: YES), the moving distance L until the acceleration becomes zero._S(M) is calculated using the following equation (7).
L_S= ΑV₀/ Dα (7)
α: Current acceleration of the vehicle (m / s²)
dα: Maximum acceleration change rate (m / s^Three)
The maximum acceleration change rate dα is determined so that the acceleration of the vehicle does not change abruptly. In this embodiment, the maximum acceleration change rate dα is 1.0 m / s.^ThreeIs set to
[0048]
Then, as shown in FIG. 9, the primary deceleration point is set as the moving distance L._S(In FIG. 9, this corresponds to the “deceleration target shift amount during acceleration”.) Correction processing is performed to move to the near side (S145), and the process proceeds to S150. On the other hand, if the vehicle is not accelerating (S140: NO), the process proceeds to S150 as it is.
[0049]
In S150, it is determined whether or not the deceleration value of the primary deceleration target node is greater than or equal to the reference deceleration. If the deceleration value of the primary deceleration target node is less than the reference deceleration (S150: NO), the vehicle speed control process is canceled and the process returns to S110. On the other hand, if the deceleration of the primary deceleration target node is equal to or greater than the reference deceleration (S150: YES), it is determined that it is necessary to decelerate such as a curve in front of the vehicle, and the process proceeds to S160.
[0050]
In S160, the corrected primary deceleration target vehicle speed V is reached until the primary deceleration target point is reached.₁₁The deceleration is calculated so as to decelerate until the deceleration starts (see area A in FIG. 8).
In subsequent S170, the corrected primary deceleration target vehicle speed V is reached until the primary deceleration target point is reached.₁₁(S170: NO), when the primary deceleration target point is reached (S170: YES), the process proceeds to S180.
[0051]
In S180, as shown in FIG. 7, based on the acceleration / deceleration of each node calculated in the previous S120, a node that ends deceleration and starts acceleration is selected. If the node is the same as the primary deceleration target node (S180: NO), the node is set as the “secondary deceleration target node”, the process proceeds to S210 and the vehicle speed is maintained (S210). On the other hand, if the node is not the same as the primary deceleration target node (S180: YES), the node is set as the “secondary deceleration target node”, and the stable traveling speed at the secondary deceleration target node is set to “secondary deceleration target vehicle speed”. V₂The process proceeds to S190. This secondary deceleration target node is a target point for the second deceleration control after the determination that the deceleration of the “primary deceleration target node” is equal to or greater than the reference deceleration in the previous S130. . The “secondary deceleration target node” corresponds to a deceleration end node and a secondary deceleration target point.
[0052]
In S190, deceleration is started toward the secondary deceleration target node set in the previous S180 (see area B in FIG. 8), and the process proceeds to S200.
In S200, the secondary deceleration target vehicle speed V is reached before reaching the secondary deceleration target node.₂(S200: NO), when the secondary deceleration target node is reached (S200: YES), the vehicle speed is maintained thereafter (S210).
[0053]
In subsequent S220, a post-curve acceleration start point is set, which is a point where acceleration starts after the vehicle passes the curve. Specifically, as shown in FIG. 7, the secondary deceleration target vehicle speed V₂Is multiplied by the acceleration target speed ratio (in this embodiment, the numerical value 1.2) to obtain a corrected acceleration target vehicle speed V_{twenty one}And Then, the corrected acceleration target vehicle speed V in a substantially curved line connecting the nodes._{twenty one}The point that becomes the value of is set as the acceleration start point after the curve.
[0054]
Then, the vehicle speed until then is maintained until the post-curve acceleration start point is reached (S230: NO, refer to “constant speed running” in FIG. 2), and when the post-curve acceleration start point is reached (S230: YES). Then, the deceleration control is finished and the vehicle is accelerated (see S240, area E in FIG. 8).
[0055]
As described above, for example, every time deceleration control is required, such as when the vehicle approaches a curve, the cruise control device of this embodiment sets the primary deceleration target point and the secondary deceleration target node as described above. As a result, stepwise deceleration control is executed with the curve entrance and curve peak as the deceleration target.
[0056]
As shown in area A of FIG. 8, before the vehicle passes the primary deceleration target point, the vehicle speed may be decelerated more than necessary due to the influence of the preceding vehicle or traffic jam. In such a case, deceleration control is stopped and acceleration control is performed according to the situation. Specifically, a travel distance (hereinafter, simply referred to as a travel distance) L when the vehicle travels at a deceleration release coefficient time with an allowable acceleration._U(M) is calculated using the following equation (8).
[0057]
L_U= V₀k + α_Uk²/2...(8)
α_U: Allowable acceleration (m / s²)
k: Deceleration release coefficient time (s)
Where allowable acceleration α_UThe acceleration is such that a vehicle occupant such as a driver does not feel uncomfortable. In this embodiment, 0.08 G (= 0.784 m / s).²) Is set. The deceleration cancellation coefficient time k is a minimum acceleration time that a vehicle passenger such as a driver does not feel uncomfortable, and is set to 1.0 s in this embodiment.
[0058]
Then, as shown in FIG. 10, the primary deceleration point is set to the travel distance L._U(In FIG. 9, “deceleration release target shift amount” corresponds to this position.) The position that has been moved to the near side is set as the deceleration release target point. Stop and perform acceleration control. This prevents the driver from feeling uncomfortable. When the vehicle speed is reduced more than necessary and becomes lower than the secondary deceleration target vehicle speed as described above, the deceleration control is canceled and the “secondary deceleration target vehicle speed V₂To control.
[0059]
[effect]
Thus, according to the cruise control apparatus of this embodiment, each node existing in front of the vehicle is detected, and the stable traveling speed V that is a vehicle speed for traveling stably when the vehicle passes through each node._TAnd the deceleration α necessary for the vehicle to decelerate to the stable traveling speed at that node before reaching the node._nAre calculated in order (S110). And the deceleration α of each node_nBased on the above, the point at which the value of the deceleration becomes the largest is selected, and the vehicle is decelerated and controlled so that the stable traveling speed at that point is reached before reaching that point (S140 to S170). Further, when the point at which the curve curve is the largest is different from the point at which the previous deceleration value is the largest and exists ahead of the vehicle (S180: present), further necessary deceleration control is performed. (S190, S200). That is, the vehicle speed control by the cruise control device of the present embodiment approaches the stepwise deceleration control on the curve performed by a general driver. Furthermore, when there is a following vehicle, it is safer because the following vehicle can easily predict the behavior of the vehicle. Therefore, vehicle speed control that does not give the driver a sense of incongruity can be realized.
[0060]
[Another example]
(1) In the cruise control device of the above embodiment, the primary deceleration target point and the secondary deceleration target point are set based on the node information detected by the navigation device 5 from the map database. You may make it set based on the receiving information from the laser radar sensor 3, the image information from an image processing apparatus, etc.
(2) In the cruise control device according to the above embodiment, the inter-vehicle control ECU 2 performs the stable travel speed V_TIs calculated for each node, but the navigation device 5 has a stable running speed V_TIs stored in advance in the map database together with the node information, and the stable traveling speed V_TMay be transmitted to the inter-vehicle control ECU 2 together with the node information. In addition, the navigation device 5 has a stable running speed V_TMay be calculated. In this way, the inter-vehicle control ECU 2 can control the stable traveling speed V_TNeed not be calculated each time, the burden on the inter-vehicle control ECU 2 can be reduced. Also, traveling speed V during traveling_T, Its running speed V_TThe navigation device 5 may store the information together with corresponding node information. In this way, for example, when traveling again on a road that has traveled before, the travel speed V when traveling previously is_TCan be read out from the navigation device 5 and used, so that the vehicle can travel at the same speed as before.
(3) In the deceleration control process of the above embodiment, the inter-vehicle control ECU 2 performs control so as to decelerate at a constant deceleration until reaching the primary deceleration target point or the secondary deceleration target node. You may make it decelerate.
(4) In the deceleration control process of the above embodiment, the navigation device 5 determines that the vehicle is at the reference deceleration rate α from the current position.₀Detects nodes that exist up to the point where the vehicle stops when decelerating at_THowever, a node having a distance from the vehicle position within 500 m, for example, may be detected from the map database. In this way, the processing is less than in the case of the above embodiment, and the burden on the navigation device 5 can be reduced.
(5) In the deceleration control process of the above embodiment, the secondary deceleration target node as the secondary deceleration target point may be reset to the near side. Specifically, the secondary deceleration target vehicle speed V is set in the same manner as the primary deceleration target point is reset in S140.₂Is multiplied by the deceleration target speed ratio, and the point that is the value in the approximate curve connecting the nodes is reset to the secondary deceleration target point. In this way, the possibility of sufficient deceleration before reaching the point where deceleration actually ends is increased.
(6) Stable travel speed V at each of the primary deceleration target point, secondary deceleration target point, and post-curve acceleration start point set by the inter-vehicle control ECU 2_TThe value may be configured to be changed by the driver. Specifically, the stable running speed V of each point_TIs multiplied by a coefficient and the value is used as the stable running speed V_TIt is conceivable to set again. In this case, the coefficient value is set to a value larger than 1 such as the numerical value 1.2 when it is desired to increase the vehicle speed as a whole. What is necessary is just to set to numerical values less than 1, such as numerical value 0.8. In this way, the driver can correct the vehicle speed control to his / her preference, so that it is possible to realize vehicle speed control that does not make the driver feel uncomfortable. In this case, the driver may input a numerical value to be set as a coefficient, or a coefficient option (for example, a coefficient numerical value 0. 0) set by the manufacturer to reflect the driver's driving preference. 8, 1.0, 1.2, etc.), and the driver may select one of these options. In addition, instead of presenting the numerical values of the coefficients, it is desirable that the names of the soft mode, the normal mode, the sports mode, and the like are given in order from the smallest coefficient values so that the driver can easily understand. It should be noted that the above-mentioned options may be set in advance when manufacturing the cruise control apparatus of the present embodiment, or the driver may set it if it can be changed later. Good.
[Brief description of the drawings]
FIG. 1 is a schematic block diagram illustrating a system configuration of a cruise control apparatus according to an embodiment.
FIG. 2 is a time chart of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 3 is a flowchart of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 4 is an explanatory diagram 1 of deceleration control executed by the cruise control device according to the embodiment.
FIG. 5 is an explanatory diagram of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 6 is an explanatory diagram of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 7 is an explanatory diagram of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 8 is an explanatory diagram of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 9 is an explanatory diagram of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 10 is an explanatory diagram of deceleration control executed by the cruise control apparatus according to the embodiment.
FIG. 11 is a time chart of deceleration control executed by a conventional cruise control device.
[Explanation of symbols]
2 ... Electronic controller for inter-vehicle distance control (inter-vehicle distance control ECU), 3 ... Laser radar sensor,
4 ... Brake electronic control device (brake ECU), 5 ... Navigation device,
6 ... Electronic control unit for engine control (engine ECU),
8 ... steering sensor, 10 ... yaw rate sensor, 14 ... alarm buzzer,
15 ... throttle opening sensor, 16 ... vehicle speed sensor, 18 ... brake switch,
20 ... Cruise control switch, 22 ... Cruise main switch,
24 ... Throttle actuator, 25 ... Brake actuator,
26 ... Transmission, 28 ... Body LAN

Claims (6)

Position detecting means for detecting a position where the vehicle exists;
Map information storage means for storing map information including node information;
Based on the position of the vehicle and the map information, a scheduled passage node detecting means for detecting one or more nodes that the vehicle is scheduled to pass (hereinafter referred to as a scheduled passage node);
A stable travel speed calculating means for calculating a speed for traveling stably (hereinafter referred to as a stable travel speed) when the vehicle passes through the scheduled passage node;
Vehicle speed detection means for detecting the current speed of the vehicle;
Based on the position of the vehicle, the scheduled passage node, the stable traveling speed at the scheduled passage node, and the current speed of the vehicle, the vehicle passes from the current speed of the vehicle before reaching the scheduled passage node. Deceleration calculation means for calculating a deceleration (hereinafter referred to as deceleration) for decelerating to a stable traveling speed at the scheduled node;
Based on the deceleration calculated by the deceleration calculation means, the node that has the largest deceleration (hereinafter referred to as the maximum deceleration node) is selected from the scheduled passage nodes, and the maximum deceleration node is selected. The maximum deceleration node is set as a target point (hereinafter referred to as a primary deceleration target point) when the deceleration control is performed for the first time from the start, and the stable node is located farther than the maximum deceleration node among the scheduled passing nodes. A target point (hereinafter referred to as a secondary deceleration target) for the second deceleration control after selecting the maximum deceleration node after selecting the one whose traveling speed reverses from decreasing to increasing (hereinafter referred to as a deceleration end node). A deceleration target point setting means for setting the deceleration end node to
Deceleration means for decelerating the vehicle;
The speed of the vehicle is controlled so as to reach a stable traveling speed at the maximum deceleration node before the deceleration means is controlled to reach the primary deceleration target point, and the primary deceleration target point and the secondary deceleration are further controlled. A control means for controlling the speed of the vehicle so as to reach a stable traveling speed at the deceleration end node before reaching the secondary deceleration target point by controlling the deceleration means when the target point is different;
Equipped with a,
The deceleration target point setting means resets the primary deceleration target point closer to the front than the maximum deceleration node . The vehicle speed control device according to claim 1 , wherein
The vehicle speed control device, wherein the deceleration target point setting means resets the secondary deceleration target point in front of the deceleration end node. The vehicle speed control device according to claim 1 or 2 ,
When the vehicle is accelerating, the deceleration target point setting means sets the primary deceleration target point and the secondary deceleration for the travel distance that is longer than when the vehicle is traveling at a constant speed due to the acceleration. A vehicle speed control device characterized by resetting the target point to the near side. In the vehicle speed control device according to any one of claims 1 to 3 ,
Accelerating means for accelerating the vehicle,
The control means stops the deceleration control when the speed of the vehicle reaches the stable traveling speed at the maximum deceleration node on the near side of the primary deceleration target point, while the primary deceleration The vehicle is accelerated by controlling the acceleration means when the vehicle speed is lower than the stable travel speed at the maximum deceleration node on the near side of the target point. Vehicle speed control device. In the vehicle speed control device according to any one of claims 1 to 4 ,
Accelerating means for accelerating the vehicle,
The control means sets the vehicle speed to a stable traveling speed at the deceleration end node between the primary deceleration target point and a point at which the vehicle starts acceleration (hereinafter referred to as an acceleration start point). When it reaches, the deceleration control is stopped, while the speed of the vehicle becomes lower than the stable traveling speed at the deceleration end node between the primary deceleration target point and the acceleration start point. In this case, the vehicle speed control apparatus controls the acceleration by controlling the acceleration means. A program for causing a computer to function as deceleration calculation means, deceleration target point setting means, control means, and stable traveling speed calculation means in the vehicle speed control device according to any one of claims 1 to 5 .

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