JP5991220B2 - Driving assistance device - Google Patents

Description

  The present invention relates to a driving support device.

  2. Description of the Related Art Conventionally, a technique is known in which a speed pattern is generated according to a travel route of a vehicle, and driving assistance is performed for a vehicle driver based on the speed pattern. For example, Patent Document 1 discloses a technique for setting driving acceleration and deceleration sections on a travel route, generating a target speed control amount in each section, and performing driving support so that traveling with good fuel efficiency can be achieved. Yes.

JP 2011-173524 A

  However, in the prior art, in the setting of the speed pattern and the target speed control amount, the presence of a preceding body such as a preceding vehicle existing in front of the travel route of the vehicle is not taken into consideration. For this reason, even if driving assistance is performed based on the generated vehicle speed pattern, there is a possibility that it may approach the preceding body unnecessarily, and fuel consumption may deteriorate due to sudden braking.

  The present invention has been made in view of the above, and in driving support for a vehicle based on a vehicle speed pattern, a driving support device capable of suppressing unnecessary approach to a preceding body existing in front of the traveling path of the vehicle. The purpose is to provide.

  In order to solve the above problems, a driving support device according to the present invention is a driving support device that generates a speed pattern according to a travel route of a vehicle and performs driving support based on the speed pattern. A plurality of decelerating means, and when the approach to the preceding body is predicted, wherein the distance between the preceding body existing in front of the traveling path of the vehicle and the vehicle is equal to or less than a predetermined value; One of the deceleration means that can avoid the approach is selected, and the driving assistance based on the deceleration speed pattern when the selected deceleration means is executed is changed.

  In addition, when there are a plurality of deceleration means that can avoid the approach, it is preferable that the driving support apparatus selects a deceleration means that requires the least power for deceleration.

  Further, the driving support device estimates a speed pattern of the preceding body based on the current position and current speed of the preceding body, and the deceleration generated by the current position and current speed of the vehicle and the plurality of deceleration units. Based on the above, the deceleration speed pattern when the plurality of deceleration means is executed is estimated, the speed pattern of the preceding body is compared with the deceleration speed pattern, and the preceding body after a predetermined time from the present time It is preferable to estimate the distance to the vehicle and determine that the approach to the preceding body can be avoided when the estimated value of the distance is equal to or greater than a predetermined value.

  In addition, the driving support device described above may accelerate the driver when the average vehicle speed of the vehicle is equal to or lower than a predetermined value after changing to driving support based on the deceleration speed pattern when the selected deceleration unit is executed. It is preferable to provide driving assistance to encourage.

  The driving assistance device according to the present invention selects a deceleration means that can avoid approaching the preceding body in a situation where the vehicle is likely to approach the preceding body when the vehicle is performing driving assistance based on the speed pattern. And since it changes to the driving assistance based on the deceleration speed pattern by this selected deceleration means, it becomes possible to avoid approaching the preceding body of a vehicle in advance. Thereby, there is an effect that unnecessary approach to the preceding vehicle can be suppressed in the driving assistance based on the vehicle speed pattern.

FIG. 1 is a block diagram showing a schematic configuration of a driving support apparatus according to an embodiment of the present invention. FIG. 2 is a flowchart of the deceleration support control when the preceding vehicle approaches, which is performed by the operation control device of the present embodiment. FIG. 3 is a time chart for explaining determination criteria for selecting a deceleration means in the deceleration support control of FIG. FIG. 4 is a flowchart of recovery control after execution of the deceleration support control performed by the operation control device of the present embodiment. FIG. 5 is a time chart for explaining a criterion for changing the support state from the deceleration side to the coasting side in the recovery control of FIG. FIG. 6 is a diagram for explaining determination criteria for selecting the coasting side and acceleration side support states in the recovery control of FIG. 4.

  Embodiments of a driving support apparatus according to the present invention will be described below with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated.

  First, with reference to FIG. 1, the structure of the driving assistance device which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a block diagram showing a schematic configuration of a driving support apparatus according to an embodiment of the present invention.

  As shown in FIG. 1, the driving support device 1 is mounted on a vehicle 2 as a host vehicle, and includes a preceding vehicle recognition device 3, a prefetch information acquisition device 4, a driving state detection device 5, and an ECU (Electronic Control Unit). An electronic control unit) 6 and an HMI (Human Machine Interface) device 7 are provided.

  In the driving support device 1, the ECU 6 controls the HMI device 7 based on information acquired by the preceding vehicle recognition device 3, the prefetch information acquisition device 4, and the driving state detection device 5, and sends various driving support information to the driving of the vehicle 2. By presenting it to the driver, the driver can support safe driving of the vehicle 2. In addition, the driving support device 1 supports safe driving of the vehicle 2 by the ECU 6 appropriately controlling the engine 8, transmission 9, motor generator 10, and hydraulic brake 11 of the vehicle 2.

  In particular, in the present embodiment, the driving support device 1 generates a vehicle speed pattern according to the travel route of the vehicle 2 and performs driving support for the driver so that the vehicle 2 travels according to the generated speed pattern. For example, the driving support device 1 uses the generated speed pattern as a target speed control amount, and supports the target speed control amount so as to be achieved.

The vehicle 2 is a hybrid vehicle that includes an engine 8 and a motor generator 9 as a driving source for traveling for driving the drive wheels to rotate. The vehicle 2 travels by converting the power output from the engine 8 into an appropriate driving force by the transmission 9 and transmitting the driving force to the driving wheels. The transmission 9 has a plurality of gear stages having different gear ratios, and can output a desired driving force by being shifted to an appropriate gear stage according to the traveling state of the vehicle 2. While the vehicle 2 operates with the engine being as efficient as possible, the motor generator 10 can compensate for excess or deficiency of power or engine braking force. The vehicle 2 can perform regenerative power generation by the motor generator 10 during traveling.

  The preceding vehicle recognition device 3 recognizes a preceding vehicle traveling in front of the vehicle 2 and detects information related to the preceding vehicle (the distance between the vehicle 2 and the preceding vehicle and the relative speed of the preceding vehicle with respect to the vehicle 2). Specifically, the preceding vehicle recognition device 3 is realized by a stereo camera, a millimeter wave radar, or the like that can recognize disturbances such as surrounding vehicles, obstacles, and pedestrians.

  The prefetch information acquisition device 4 acquires prefetch information of the travel route of the vehicle 2. The prefetch information is travel path information such as a gradient and a radius of curvature in a travel path ahead of the current position of the vehicle 2. The prefetch information acquisition device 4 can detect the prefetch information by detecting the own vehicle position and referring to the map information of the travel route based on the own vehicle position. The prefetch information acquisition device 4 can be realized by using, for example, a car navigation system capable of detecting own vehicle position information and travel route map information.

  The driving state detection device 5 detects various information related to the driving state of the vehicle 2. Specifically, the driving state detection device 5 includes a driver operation state such as an accelerator opening degree and a brake depression force, a control state of the power train of the vehicle 2 such as an engine speed, a driving force, and a regeneration amount, and a vehicle speed of the vehicle 2. And sensors that detect information related to the overall driving state of the vehicle 2 such as a traveling state such as acceleration and acceleration.

  The ECU 6 controls each part of the vehicle 2 based on various information input from various state detection devices of the vehicle 2. The preceding vehicle recognition device 3, the prefetch information acquisition device 4, the driving state detection device 5, the HMI device 7, the engine 8, the transmission 9, the motor generator 10, and the hydraulic brake 11 are connected to the ECU 6, respectively.

  In this embodiment, the ECU 6 is a vehicle with optimum fuel consumption based on the pre-read information acquired from the preceding vehicle recognition device 3, the pre-read information acquisition device 4, the driving state detection device 5, the information on the driving state of the vehicle and the driver, and the like. An “optimum fuel consumption speed pattern” that allows the vehicle to travel is generated. Then, according to the generated optimum fuel consumption speed pattern, the HMI device 7, the engine 8, the transmission 9, the motor generator 10, and the hydraulic brake 11 are controlled so that the vehicle 2 travels along the optimum fuel consumption speed pattern. Driving assistance based on fuel consumption speed pattern.

  The optimum fuel consumption speed pattern is generated by appropriately combining a plurality of traveling patterns including, for example, acceleration traveling and deceleration traveling, thereby improving fuel consumption. During acceleration traveling with the optimum fuel consumption speed pattern, the vehicle 2 is accelerated with acceleration with good engine thermal efficiency, for example, by driving the engine 8.

  Further, the ECU 6 predicts an approach to a preceding vehicle (preceding body) that travels in front of the vehicle 2 while the vehicle 2 is traveling, so as to avoid a deterioration in fuel consumption due to the approach, a predetermined inter-vehicle distance from the preceding vehicle So that the vehicle 2 can travel at a reduced speed. The vehicle 2 has a plurality of deceleration means that can generate different decelerations. Since the vehicle 2 of the present embodiment is a hybrid vehicle, the vehicle 2 includes, for example, the following three types of deceleration means (1) to (3).

  (1) Free run: The gear stage of the transmission 9 is switched to the neutral range (N range), and the output of the engine 8 is stopped. Decelerate by inertia. This is an efficient deceleration method with no waste and minimal impact on fuel consumption.

  (2) Emblem regeneration: The accelerator 2 is turned off, the vehicle 2 is decelerated by the engine brake, and the motor generator 10 is operated as a generator to decelerate by the regenerative brake. Although kinetic energy can be recovered by regeneration, a recovery loss (such as an electric conversion loss of a motor or a battery) occurs. The impact on fuel consumption deterioration is relatively small.

  (3) Hydraulic brake: The hydraulic brake 11 is controlled to decelerate. Since all the kinetic energy for deceleration is released as heat energy, it has a large effect on fuel consumption.

  The ECU 6 estimates a “deceleration speed pattern” indicating the movement transition of the vehicle 2 when executing these deceleration means in the deceleration support control when the preceding vehicle approaches, and based on the estimated deceleration speed pattern, A speed reduction means that can secure a predetermined inter-vehicle distance is extracted. Then, driving support for decelerating driving is performed based on the deceleration speed pattern by the extracted deceleration means. Note that the ECU 6 selects the one with less deceleration power when there are a plurality of deceleration units that can ensure the inter-vehicle distance. The deceleration power is power necessary for the deceleration means to decelerate, and is related to deceleration. As the deceleration means has a larger deceleration, the deceleration power increases. From the viewpoint of improving fuel efficiency, it is preferable that the speed reduction means to be selected has as little deceleration power as possible.

  Further, the ECU 6 executes the above-described deceleration assist control when approaching the preceding vehicle, can ensure a sufficient inter-vehicle distance from the preceding vehicle, and avoids the possibility of deterioration in fuel consumption, and then recovers the vehicle traveling state from the deceleration traveling. For recovery control. In the recovery control, considering the pre-reading information, the support state based on the deceleration speed pattern is switched to the inertial support state using the deceleration means whose deceleration is smaller than the deceleration means selected in the deceleration support control, or acceleration. Switch to the support state on the acceleration side where the car is running.

  The ECU 6 allows the preceding vehicle detection unit 61, the speed pattern generation unit 62, the support state selection unit 63, and the driving support so that the deceleration support control when approaching the preceding vehicle and the recovery control after the deceleration support control can be performed. Each function of the control unit 64 is configured to be realized.

  The preceding vehicle detection unit 61 detects the presence of the preceding vehicle based on information on the surrounding disturbance detected by the preceding vehicle recognition device 3. When the preceding vehicle detection unit 61 detects the preceding vehicle, the preceding vehicle detection unit 61 acquires information such as an inter-vehicle distance between the vehicle 2 and the preceding vehicle and a relative speed of the preceding vehicle with respect to the vehicle 2 from the preceding vehicle recognition device 3.

  The speed pattern generation unit 62 generates speed patterns for the vehicle 2 and the preceding vehicle. The speed pattern generation unit 62 is configured to make the vehicle 2 travel at an optimum fuel consumption based on the prefetch information acquired by the prefetch information acquisition device 4 and information on the driving state of the vehicle 2 detected by the driving state detection device 5. An optimum fuel consumption speed pattern used in fuel consumption control and a deceleration speed pattern used in deceleration support control when a preceding vehicle approaches are generated. Further, the speed pattern generation unit 62 detects the preceding vehicle based on the information related to the driving state of the preceding vehicle acquired by the preceding vehicle recognition device 3 when the preceding vehicle detecting unit 61 detects the presence of the preceding vehicle. Estimate the velocity pattern.

  The assistance state selection unit 63 appropriately selects a speed pattern used for driving assistance according to the degree of approach of the inter-vehicle distance between the vehicle 2 and the preceding vehicle. The support state selection unit 63 compares the speed patterns of the vehicle 2 and the preceding vehicle, and estimates the degree of approach between the two at a predetermined future time, for example. Then, when it is predicted that both approach more than necessary, a deceleration means that can avoid the approach is selected so that a sufficient inter-vehicle distance can be secured, and the deceleration speed pattern when this selected deceleration means is executed The support state for the driver of the vehicle 2 is switched so as to perform the driving support based on it. Further, after avoiding the approach to the preceding vehicle, the support state selection unit 63 appropriately changes from the decelerating travel to the support state such as reacceleration and coasting according to the travel state of the vehicle 2.

  The driving support control unit 64 controls the driving support operation for the driver of the vehicle 2. In the present embodiment, the driving support control unit 64 performs driving support based on the speed pattern selected by the support state selection unit 63. Specifically, the driving support operation controls the HMI device 7 based on the speed pattern selected by the support state selection unit 63 such as the optimum fuel consumption speed pattern and the deceleration speed pattern, and teaches the driver the timing of the accelerator operation. In other words, the engine 8 and the transmission 9 are controlled to automatically travel along the optimum fuel consumption speed pattern.

  The ECU 6 is physically an electronic circuit mainly composed of a known microcomputer including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an interface, and the like. Each of the functions of the ECU 6 described above loads various application programs held in the ROM into the RAM and executes them by the CPU, thereby operating various devices in the vehicle 2 under the control of the CPU, and in the RAM and ROM. This is realized by reading and writing data.

  The HMI device 7 is a support device that can output driving support information that is information for supporting driving of the vehicle 2, and is a device that provides driving support information to the driver. The HMI device 7 is an in-vehicle device, and includes, for example, a display device (visual information display device) or a speaker (auditory information output device) provided in the vehicle interior of the vehicle 2. The HMI device 7 provides driving support information to the driver by outputting visual information (graphic information, character information), auditory information (voice information, sound information), etc., and guides the driving operation of the driver. The HMI device 7 supports the realization of the target value by the driving operation of the driver by providing such information. The HMI device 7 is electrically connected to the ECU 6 and controlled by the ECU 6.

  Next, with reference to FIGS. 2-6, operation | movement of the driving assistance apparatus 1 which concerns on this embodiment is demonstrated.

  First, with reference to FIGS. 2 and 3, the deceleration support control when the preceding vehicle approaches will be described. FIG. 2 is a flowchart of the deceleration support control when the preceding vehicle approaches, which is performed by the driving control device of the present embodiment, and FIG. 3 illustrates a criterion for selecting a deceleration means in the deceleration support control of FIG. It is a time chart for doing.

  In the time chart of FIG. 3, the horizontal axis indicates the future time from the current time, and the vertical axis indicates the travel positions of the vehicle 2 and the preceding vehicle. In FIG. 3, the time transition of the future travel position of the preceding vehicle based on the estimated speed pattern of the preceding vehicle is shown by a solid line. Moreover, the time transition of the future travel position of the vehicle 2 by the several speed pattern of the own vehicle 2 is also shown. More specifically, the time transition of the future travel position of the vehicle 2 based on the optimum fuel consumption speed pattern is indicated by a two-dot chain line, and the future of the vehicle 2 based on the deceleration speed pattern when the vehicle is decelerated by free-run control. The time transition of the travel position is indicated by a dotted line, and the time transition of the travel position of the vehicle 2 based on the deceleration speed pattern when the emblem regeneration is performed is indicated by a dashed line.

  As a premise that the deceleration assistance control shown in the flowchart of FIG. 2 is performed, the driving assistance control unit 64 of the ECU 6 performs driving assistance based on the optimum fuel consumption speed pattern that allows the vehicle to travel with the optimum fuel consumption. And The optimum fuel consumption speed pattern is generated by the speed pattern generation unit 62 based on static information depending on the external infrastructure such as the road surface gradient and curvature of the destination of the vehicle 2, the stop line and the legal speed. As the optimum fuel consumption speed pattern, a steady running maintaining a constant vehicle speed, an acceleration running with a predetermined acceleration, or the like is appropriately selected.

  The processing of the flowchart shown in FIG. 2 is executed by the ECU 6 when, for example, the presence of a preceding vehicle is detected on the travel route while driving support based on a predetermined optimum fuel consumption speed pattern is being performed while the vehicle 2 is traveling. To be implemented. Hereinafter, the deceleration support control when the preceding vehicle approaches will be described according to the flowchart of FIG. 2 with reference to FIG.

  In step S <b> 101, the preceding vehicle is detected by the preceding vehicle detection unit 61. The preceding vehicle detection unit 61 monitors information acquired by the preceding vehicle recognition device 3 and detects the presence of the preceding vehicle. When the preceding vehicle detection unit 61 detects the preceding vehicle, the preceding vehicle detection unit 61 acquires information such as an inter-vehicle distance from the preceding vehicle and a relative speed from the preceding vehicle recognition device 3 and outputs the information to the speed pattern generation unit 62.

  In step S102, the speed pattern generator 62 estimates the speed pattern of the preceding vehicle. The speed pattern generation unit 62 estimates the speed pattern of the preceding vehicle using information such as the inter-vehicle distance and the relative speed with the preceding vehicle acquired by the preceding vehicle detection unit 61 in step S101. The speed pattern of the preceding vehicle may be estimated, for example, assuming that the vehicle travels constantly at the current vehicle speed of the preceding vehicle, or when the preceding vehicle is currently accelerating, the current acceleration is maintained at a constant acceleration. It may be estimated on the assumption that a uniform acceleration motion is performed. Alternatively, the prefetch information may be acquired from the prefetch information acquisition device 4 and the speed pattern may be estimated based on the prefetch information, for example, “Decelerate to 30 km / h after 100 m”. In the example of FIG. 3, a speed pattern for steady running at the current vehicle speed of the preceding vehicle is estimated.

  In step S103, the support state selection unit 63 compares the optimum fuel consumption speed pattern used for the current driving support with the speed pattern of the preceding vehicle estimated in step S102. Specifically, as shown in FIG. 3, the inter-vehicle distance between the optimum fuel consumption speed pattern and the speed pattern of the preceding vehicle is compared, and the vehicle crosses before any future time T (for example, after 3 seconds). It is determined whether or not the distance between the vehicle 2 and the preceding vehicle is equal to or less than a predetermined value at a future time T. In addition, the predetermined value of the inter-vehicle distance used for this determination is set in consideration of an arbitrary margin considering the safety of the vehicle 2.

  In step S <b> 104, the support state selection unit 63 confirms whether or not the vehicle 2 has a possibility of fuel consumption deterioration based on the result of the determination process in step 103. In step S103, the support state selection unit 63 determines that the optimal fuel consumption speed pattern intersects the preceding vehicle speed pattern by the future time T, or the optimal fuel consumption speed pattern and the preceding vehicle speed pattern at the future time T. When the inter-vehicle distance is close to a predetermined value or less, it is determined that there is a possibility that the vehicle 2 may come into contact with the preceding vehicle, and that the driver may perform a brake operation to deteriorate fuel consumption. On the other hand, if the inter-vehicle distance between the optimum fuel consumption speed pattern and the speed pattern of the preceding vehicle is greater than or equal to a predetermined value at the future time T, the inter-vehicle distance can be sufficiently ensured between the vehicle 2 and the preceding vehicle. The brake operation is not performed, and it is determined that the fuel consumption does not deteriorate. If the result of determination in step S104 is that there is a possibility of fuel consumption deterioration, the process proceeds to step S106, and if there is no possibility of fuel consumption deterioration, the process proceeds to step S105.

  In the example of FIG. 3, at the time t before the future time T, the optimum fuel consumption speed pattern intersects the preceding vehicle speed pattern. That is, if the vehicle 2 continues traveling in the current driving state, there is a high possibility that the vehicle 2 will come into contact with the preceding vehicle. Therefore, the driver may perform a braking operation before that, and the fuel efficiency may deteriorate. It is determined to be a thing.

  In step S105, as a result of the determination in step S104, there is no possibility of deterioration in fuel consumption, and no contact with the preceding vehicle has been predicted. Therefore, the assistance state selection unit 63 maintains the assistance state based on the optimum fuel consumption vehicle speed pattern. In response to this, the driving support control unit 64 continues driving support based on the optimum fuel efficiency vehicle speed pattern. The driving support operation by the driving support control unit 64 may notify the driver of information related to driving support via the HMI device 7, or the vehicle 2 is automatically controlled by controlling the engine 8 and the transmission 9. Further, control intervention may be performed so that the vehicle travels based on a desired optimum fuel consumption speed pattern. When the process of step S105 is completed, this control flow ends.

  In step S106, as a result of the determination in step S104, there is a possibility that the fuel consumption may deteriorate, and contact with the preceding vehicle is predicted. Therefore, the assist state selection unit 63 selects the deceleration means with the least deceleration power, and generates the speed pattern. The unit 62 estimates a deceleration vehicle speed pattern when executing the selected deceleration means.

  In the process of step S <b> 106, first, the support state selection unit 63 selects the deceleration unit with the minimum deceleration power among the plurality of deceleration units included in the vehicle 2. When returning from the subsequent step S108, that is, when the deceleration means has already been selected, the one having the smallest deceleration power is selected next to the currently selected deceleration means. The deceleration power increases as the deceleration increases. As the deceleration power increases, the degree of fuel consumption deterioration increases. In the present embodiment, as described above, there are three speed reducing means: (1) free run, (2) emblem regeneration, and (3) hydraulic brake. The deceleration that can be generated by these deceleration means increases in the order of (1) free run → (2) emblem regeneration → (3) hydraulic brake. Therefore, the deceleration power also increases in this order. In other words, in the present embodiment, there are the following three patterns (i) to (iii) for selecting the deceleration means in step S106.

(I) If the current deceleration means is not selected, select free run. (Ii) If the currently selected deceleration means is free run, select emblem regeneration. (Iii) Currently selected deceleration. If the means is emblem regeneration, select hydraulic brake

In the process of step S106, next, the speed pattern generation unit 62 estimates a deceleration speed pattern when the deceleration means selected by the support state selection unit 63 is executed in this way. The speed pattern generation unit 62 dynamically generates a deceleration speed pattern in consideration of the characteristics of the power train (power transmission system) of the vehicle 2 related to each deceleration means. The speed pattern generation unit 62 can calculate, for example, a vehicle deceleration that can be generated by each deceleration unit by the following equation.
Vehicle deceleration = deceleration power / (vehicle weight x current vehicle speed) + gradient resistance + other vehicle resistance

  Here, the “deceleration power” in the above formula is the power (kW) required for deceleration set for each deceleration unit as described above. An example of the setting value of the deceleration power is, for example, 0 (kW) for free run, 5 (kW) for emblem regeneration, and 20 (kW) for hydraulic brake. Further, the deceleration power of each deceleration unit may be variable depending on the state of the vehicle 2 such as the remaining battery level. The speed pattern generation unit 62 generates the deceleration speed pattern from the present time by sequentially calculating the vehicle deceleration calculated in this way by predicting the future in 1 second, 2 seconds, 3 seconds, and the like. . When the process of step S106 is completed, the process proceeds to step S107.

  In step S107, the support state selection unit 63 compares the deceleration speed pattern estimated in step S106 with the speed pattern of the preceding vehicle. Specifically, as in the process of step S103, the support state selection unit 63 compares the inter-vehicle distance between the deceleration speed pattern and the speed pattern of the preceding vehicle as shown in FIG. It is determined whether or not the vehicle crosses before time T (for example, after 3 seconds), and whether or not the distance between the vehicle 2 and the preceding vehicle is equal to or less than a predetermined value at future time T.

  In step S108, based on the result of the determination process in step 107, the support state selection unit 63 determines whether or not deterioration of fuel efficiency can be avoided by vehicle support of the deceleration speed pattern. As in the process of step S104, the support state selection unit 63 determines that the deceleration speed pattern intersects the preceding vehicle speed pattern by the future time T in step S107 or the preceding deceleration speed pattern at the future time T. When the inter-vehicle distance between the vehicle and the vehicle speed pattern is close to a predetermined value or less, the vehicle 2 may still come into contact with the preceding vehicle, and the driver's braking operation may occur. It is determined that it cannot be avoided. On the other hand, when the inter-vehicle distance between the deceleration speed pattern and the speed pattern of the preceding vehicle is greater than or equal to a predetermined value at the future time T, a sufficient inter-vehicle distance can be secured between the vehicle 2 and the preceding vehicle. Therefore, it is determined that deterioration in fuel consumption can be avoided. If the result of determination in step S108 is that it is possible to avoid deterioration in fuel efficiency, the process proceeds to step S109. If the fuel efficiency deterioration cannot be avoided, the process returns to step S106, the speed reduction means having the smallest deceleration power is selected again after the speed reduction means selected this time, and the determination of the fuel efficiency deterioration avoidance is repeated.

  In the example of FIG. 3, first, a free run having the smallest deceleration power is selected from among a plurality of deceleration means, and the free-run deceleration speed pattern and the vehicle speed pattern of the preceding vehicle are compared. As a result, at the future time T, the inter-vehicle distance between the deceleration speed pattern and the preceding vehicle speed pattern becomes a predetermined value or less, and the inter-vehicle distance between the vehicle and the preceding vehicle becomes insufficient. Deterioration can be predicted.

  For this reason, next, the emblem regeneration with the least deceleration power after the free run is selected from among the plurality of deceleration means, and the deceleration speed pattern of the emblem regeneration is compared with the vehicle speed pattern of the preceding vehicle. As a result, the inter-vehicle distance between the deceleration speed pattern and the preceding vehicle speed pattern becomes greater than a predetermined value at a future time T, and a sufficient inter-vehicle distance can be ensured between the vehicle and the preceding vehicle. It is determined that deterioration in fuel consumption can be avoided. Then, the support state based on the current optimum fuel consumption speed pattern is switched to the support state based on the deceleration vehicle speed pattern of the emblem regeneration.

  In the processing of steps S106 to S108, there may be a case where deterioration in fuel consumption cannot be avoided even by using a deceleration means having the maximum deceleration power ("hydraulic brake" in this embodiment). In this case, there is a possibility of a collision with the preceding vehicle, and it is necessary to start deceleration immediately. For example, the deceleration is set as deceleration = (relative speed with the preceding vehicle) / (future time T). Based on the deceleration, driving support for decelerating driving can also be performed. In order to realize this deceleration, for example, a plurality of deceleration means may be combined and executed.

  In addition, the “future time T”, which is the main comparison reference when comparing the speed patterns, is appropriately changed according to the current vehicle state (EV traveling, engine operation, regeneration, hydraulic brake), etc. May be. For example, in response to a request such as not wanting to apply a hydraulic brake during regeneration, it is possible to make the transition difficult by taking a longer time T. Similarly, the margin of the inter-vehicle distance may be changed as appropriate.

  In step S109, as a result of the determination in step S108, it has become possible to avoid deterioration in fuel consumption. Therefore, in order to respond to the preceding vehicle, the support state based on the current optimum fuel consumption speed pattern is displayed in step S106. The state is changed to the support state based on the deceleration speed pattern of the selected deceleration means. In response to this, the driving support control unit 64 executes driving support based on the deceleration speed pattern changed by the support state selection unit 63.

  The driving support operation by the driving support control unit 64 may notify the driver of information related to driving support based on the deceleration speed pattern via the HMI device 7, or the engine 8, the transmission 9, the motor generator 10, Control intervention may be performed by controlling the hydraulic brake 11 so that the vehicle 2 automatically travels based on a desired deceleration speed pattern. When information is presented by the HMI device 7, for example, when the selected decelerating means is emblem regeneration, information that prompts the accelerator to be turned off, and in the case of brake, information that informs that it is necessary to start the brake. Can be notified by screen or sound. Further, when performing control intervention, the deceleration of the selected speed reduction means may be output as it is through control intervention, or may be gradually performed by looking at the driver's condition. When the process of step S109 is completed, this control flow ends.

  In the flowchart of FIG. 2 described above, the process of estimating the deceleration speed pattern of the deceleration means selected from a plurality and comparing with the vehicle speed pattern of the preceding vehicle is performed until the avoidance determination for the deterioration of fuel consumption is made. Although the deceleration power is gradually increased in order from the smallest, the deceleration speed pattern of all the deceleration means is estimated at one time and compared with the preceding vehicle vehicle speed pattern. Alternatively, a configuration in which the one with the least power is selected may be used.

  2 is based on the premise that the vehicle 2 is traveling in the optimum fuel consumption speed pattern, but the first decelerating means selected according to the state of the vehicle 2 may be appropriately changed. In this case, for example, when the state of the vehicle 2 is accelerating (accelerator on), a free run with the least deceleration power is selected as in the flowchart of FIG. 2, but the vehicle state is coasting (free run). In the case of, the emblem regeneration with the least deceleration power after the free run is selected first. Further, when the vehicle is in the accelerator off state, the regenerative brake is selected.

  Next, recovery control after execution of deceleration support control will be described with reference to FIGS. FIG. 4 is a flowchart of recovery control after execution of the deceleration support control performed by the operation control device of the present embodiment.

  The recovery control process shown in the flowchart of FIG. 4 is performed by the ECU 6 after the deceleration support control when the preceding vehicle approaches as described with reference to FIGS. Hereinafter, the recovery control after execution of the deceleration support control will be described with reference to FIGS.

  As a premise that the recovery control after execution of the deceleration support control shown in FIG. 4 is performed, the drive support control unit 64 of the ECU 6 performs the drive support based on the deceleration speed pattern of the deceleration means selected by the above-described deceleration support control. It shall be. In this recovery control, depending on the traveling state of the vehicle 2 after the deceleration support control, the driving support by the deceleration means selected in the deceleration support control (also described as “deceleration-side support state”) is continued. Change from the speed reduction means selected in the speed reduction support control to driving support by speed reduction means with a small one-step deceleration power (also referred to as “coast side support”), or driving support based on acceleration travel (acceleration side support) ).

  In step S <b> 201, the speed pattern generation unit 62 acquires prefetch information (information such as a gradient, a curvature, and a pause position) ahead of the travel route of the vehicle 2 from the prefetch information acquisition device 4.

  In step S202, the speed pattern generation unit 62 estimates a coasting speed pattern when coasting at the current speed.

  If the vehicle 2 continues to be decelerated with the deceleration by the deceleration means selected in the deceleration support control, the fuel consumption can be prevented from deteriorating. However, if the vehicle is decelerated excessively by the deceleration support control, re-acceleration is required thereafter, and as a result, the fuel consumption may deteriorate. Therefore, it is important at which timing the deceleration support control ends. In order to determine this timing, a future inertial speed pattern is calculated using a deceleration that is slower than the deceleration by the deceleration means selected in the deceleration support control.

  Here, as described above, the running state in the case where the deceleration means with a small one-step deceleration power is executed from the deceleration means selected in the deceleration support control is expressed as “coasting”. For example, in the present embodiment, the deceleration means used for “coasting” can be selected as follows.

-Select emblem regeneration when the deceleration means being executed in deceleration support control is a hydraulic brake-Select free run when the deceleration means being executed in deceleration support control is emblem regeneration

  In step S203, it is determined by the support state selection unit 63 whether or not there is no possibility of deterioration in fuel consumption when the support is changed to the coasting support selected in step S202. As in step S104 of the flowchart of FIG. 2, the support state selection unit 63 compares the inertia speed pattern estimated in step 202 with the estimated speed pattern of the preceding vehicle, so that an arbitrary future time T (for example, after 3 seconds). It is determined whether or not the inter-vehicle distance is equal to or greater than a predetermined value. Then, when the inter-vehicle distance is equal to or greater than a predetermined value, it is determined that a sufficient inter-vehicle distance from the preceding vehicle can be secured even if the driving assistance based on the coasting speed pattern is executed, and there is no possibility of deterioration in fuel consumption. As a result of the determination in step S203, if there is no possibility that the fuel consumption deteriorates, the process proceeds to step S205, and if not, the process proceeds to step S204.

  Here, the determination process in step S203 will be described with reference to FIG. FIG. 5 is a time chart for explaining a criterion for changing the support state from the deceleration side to the coasting side in the recovery control of FIG.

  The outline of the configuration of the time chart of FIG. 5 is the same as the time chart of FIG. In FIG. 5, the time transition of the future travel position of the preceding vehicle based on the speed pattern of the preceding vehicle is shown by a solid line. Further, the time transition of the future traveling position of the vehicle 2 based on the deceleration speed pattern by the deceleration means selected in the deceleration support control is indicated by a one-dot chain line, and the future traveling position of the vehicle 2 when the coasting speed pattern is executed. The time transition of is shown by a dotted line.

  In the example of FIG. 5, the coasting speed pattern when the support state is changed to the coasting side is compared with the vehicle speed pattern of the preceding vehicle. As a result, the inter-vehicle distance between the coasting speed pattern and the preceding vehicle speed pattern at the future time T becomes larger than a predetermined value, and a sufficient inter-vehicle distance can be secured between the vehicle 2 and the preceding vehicle. It is determined that no operation has occurred and there is no possibility of deterioration in fuel consumption. On the other hand, although not shown in FIG. 5, if the inter-vehicle distance between the coasting speed pattern and the preceding vehicle speed pattern is equal to or less than a predetermined value at the future time T, the coasting speed pattern has no possibility of deterioration in fuel consumption. It is determined that it is not.

  In step S204, if the support state is changed to the coasting side as a result of the determination in step S203, there is a possibility that the fuel consumption is deteriorated. Therefore, the support state selection unit 63 continues the support state on the deceleration side. That is, the support state selection unit 63 continues the deceleration support control, and continues the support state using the deceleration speed pattern of the deceleration unit selected in the deceleration support control. In response to this, the driving support control unit 64 continues to perform driving support for deceleration traveling based on the deceleration speed pattern of the deceleration means selected by the deceleration support control.

  In step S205, as a result of the determination in step S203, there is no possibility of deterioration in fuel consumption even if the support state is changed to the coasting side. Therefore, in the case of the support state using the coasting speed pattern by the support state selection unit 63, It is determined whether or not the target position can be reached. For example, the support state selection unit 63 determines whether the target position (the next re-acceleration position calculated in advance) can be reached as it is by combining the coasting speed pattern and the prefetch information. As a result of the determination in step S205, if the next target position can be reached by the coasting speed pattern, the process moves to step S206, and if not, the process moves to step S208.

  Here, the determination process in step S205 will be described with reference to FIG. FIG. 6 is a diagram for explaining determination criteria for selecting the coasting side and acceleration side support states in the recovery control of FIG. 4.

  In FIG. 6, the horizontal axis represents the travel position of the vehicle 2, and the vertical axis represents the vehicle speed of the vehicle 2. In FIG. 6, the optimum fuel consumption speed pattern set before the deceleration support control is indicated by a dotted line, and the vehicle speed transition of the vehicle 2 by the deceleration support control and the recovery control is indicated by a solid line. The right side of FIG. 6 illustrates a pattern in which it is determined that the target position can be reached by changing the coasting support state, and the left side of FIG. 6 determines that the support state change to the acceleration side is necessary. A pattern is illustrated.

  As shown on the right side of FIG. 6, even if the vehicle speed of the vehicle 2 is relatively close to the optimum fuel consumption speed pattern even after the vehicle is decelerated by the deceleration support control, the predetermined speed range is maintained even if the support state is switched to the coasting side. It can be estimated that the target position can be sufficiently reached within (for example, a range from the target speed calculated in advance to about −10 (km / h)). In this case, in step S205, it is determined that the next target position can be reached.

  On the other hand, as shown on the left side of FIG. 6, when the vehicle speed of the vehicle 2 decelerates relatively large from the optimum fuel consumption speed pattern due to deceleration by the deceleration assist control, the deceleration further proceeds when the assist state is switched to the coasting side. It can be estimated that the speed divergence from the optimum fuel consumption speed pattern becomes too large near the position and does not reach the target position within the predetermined speed range. In this case, in step S205, it is determined that the next target position cannot be reached, and in subsequent processing, the vehicle 2 is re-accelerated by changing to assistance on the acceleration side so that the vehicle 2 can reach the target position.

  In step S206, as a result of the determination in step S205, when the next target position can be reached by the coasting speed pattern, the support state selection unit 63 confirms whether or not the average speed in the current traveling state is within the allowable range. . In this step, it is determined whether conditions such as the set average speed (arrival time to the destination) are not impaired when the optimal fuel consumption speed pattern is calculated in advance. If the average speed of the current vehicle undermines these conditions, the current speed of the vehicle will be extremely low, making it difficult to improve fuel efficiency. Therefore, in the subsequent processing, the vehicle 2 is re-accelerated by changing to assistance on the acceleration side so that the average speed of the vehicle 2 is within the allowable range.

  In step S206, whether or not the average speed of the vehicle 2 is within the allowable range is determined by, for example, the target average speed V1 (target elapsed time T1 at the current position) when a travel plan based on the optimum fuel consumption speed pattern is made in advance. ) And the current average speed V2 (current elapsed time T2). When the average speeds V1 and V2 satisfy the condition of V1> V2 + α (T1 <T2-β), the average speed V2 in the current traveling state is considerably slower than the target average speed V1, and the allowable range is exceeded. (Α and β are parameters that determine the allowable range and are defined in advance). In this step, not only the target average speed information of the own vehicle 2, but also the speed of the following vehicle may be set as the target average speed when the succeeding vehicle can be recognized. The average speed may be used. As a result of the determination in step S206, if the average speed of the coasting speed pattern is within the allowable range, the process proceeds to step S207, and if not, the process proceeds to step S208.

  In step S207, when driving support of the coasting speed pattern is executed, there is no possibility of deterioration in fuel consumption, the next target position can be reached, and the current average speed of the vehicle 2 is within an allowable range. Therefore, it is determined that the coasting speed pattern can be executed, and the support state selection unit 63 changes the coasting side support state to the coasting support state. As described above, the support state on the coasting side is a support state using the deceleration unit one stage before the current deceleration unit. The driving support control unit 64 performs driving support on the coasting side based on the coasting speed pattern. When the process of step S207 is completed, this control flow ends.

  In step S208, although there is no possibility of deterioration in fuel efficiency when driving support of the coasting speed pattern is executed, the next target position cannot be reached, or the current average speed of the vehicle 2 is outside the allowable range. Therefore, the support state selection unit 63 determines that the coasting speed pattern cannot be executed and the acceleration side support should be performed, and the acceleration is calculated in consideration of the powertrain characteristics. The support state selection unit 63 selects an acceleration with no waste (minimizing fuel consumption deterioration) based on pre-read information such as the shape of the road ahead on the travel route of the vehicle 2 and information on the preceding vehicle. In addition, as a method for selecting acceleration without waste, for example, an acceleration that can minimize the total amount of energy required for acceleration traveling, such as energy consumption for acceleration traveling and energy consumption for engine start for acceleration traveling, is derived. It is possible to apply a technique such as

  In step S209, the support state selection unit 63 changes to the acceleration side support state using the acceleration calculated in step S208. The driving support control unit 64 performs driving support for acceleration traveling using the acceleration calculated in step S208. When the process of step S209 is completed, this control flow ends.

  Next, the effect of the driving support device according to the present embodiment will be described.

  The driving support device 1 of the present embodiment generates a speed pattern according to the travel route of the vehicle 2 and performs driving support based on the speed pattern. The vehicle 2 has a plurality of deceleration means. When the driving support device 1 predicts the approach to the preceding vehicle in which the distance between the preceding vehicle existing in front of the traveling route of the vehicle 2 and the vehicle 2 is a predetermined value or less, among the plurality of deceleration units, A vehicle that can avoid the approach to the preceding vehicle is selected, and the driving assistance is changed based on the deceleration speed pattern when the selected deceleration means is executed.

  With this configuration, when the vehicle 2 is performing driving assistance based on the speed pattern, in a situation where the vehicle 2 is highly likely to approach the preceding vehicle, the speed reduction means that can avoid the approach to the preceding vehicle is selected, Since it changes to the driving assistance based on the deceleration speed pattern by the selected deceleration means, it becomes possible to avoid the approach of the vehicle 2 to the preceding vehicle in advance. Thereby, unnecessary approach to the preceding vehicle can be suppressed in driving assistance based on the vehicle speed pattern. In addition, if the distance between the vehicle 2 and the preceding vehicle is shortened, the driver of the vehicle 2 feels danger and increases the chance of braking. As a result, wasteful acceleration / deceleration occurs and the fuel consumption is deteriorated. However, in the present embodiment, unnecessary approach to the preceding vehicle can be suppressed, so that deterioration in fuel consumption can be avoided.

  In addition, when there are a plurality of speed reduction means that can avoid the approach to the preceding vehicle, the driving support apparatus 1 of the present embodiment selects the speed reduction means that requires the least power for deceleration.

  With this configuration, driving assistance is performed using the deceleration means with the least deceleration power, so it is possible to minimize deterioration in fuel consumption due to deceleration traveling to avoid approaching the preceding vehicle, and from the viewpoint of improving fuel efficiency Optimal driving assistance can be performed.

  Further, the driving support device 1 of the present embodiment estimates the speed pattern of the preceding vehicle based on the current position and current speed of the preceding vehicle, and the deceleration generated by the current position and current speed of the vehicle 2 and a plurality of deceleration means. Based on the above, the deceleration speed pattern when a plurality of deceleration means is executed is estimated. Then, the speed pattern of the preceding vehicle and the deceleration speed pattern are compared to estimate the inter-vehicle distance between the preceding vehicle and the vehicle 2 after a predetermined time from the present time, and the estimated value of the inter-vehicle distance is equal to or greater than a predetermined value. When it becomes, it determines with the approach to a preceding vehicle being avoidable.

  With this configuration, a deceleration speed pattern that can sufficiently secure the inter-vehicle distance from the preceding vehicle is selected, and driving assistance based on the deceleration speed pattern is performed, so that unnecessary approach to the preceding vehicle can be more reliably suppressed. .

  In addition, the driving support device 1 according to the present embodiment changes the driving support based on the deceleration speed pattern when the selected deceleration unit is executed, and then, when the average vehicle speed of the vehicle 2 is equal to or less than a predetermined value, to the driver. Provide driving assistance to accelerate.

  With this configuration, even when the average vehicle speed of the vehicle 2 becomes extremely low due to too much emphasis on suppression of fuel consumption deterioration due to driving assistance based on the deceleration speed pattern, the vehicle 2 is quickly switched to acceleration traveling and the average speed of the vehicle 2 is set. Can be increased. As a result, it is possible to prevent the surrounding vehicles from being disturbed or obstructing the traffic flow due to the low-speed traveling of the vehicle 2.

  As mentioned above, although embodiment of this invention was described, the said embodiment was shown as an example and is not intending limiting the range of invention. The above-described embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. The above-described embodiments and modifications thereof are included in the invention described in the claims and equivalents thereof, as long as they are included in the scope and gist of the invention.

  In the above-described embodiment, a hybrid vehicle including an engine and a motor generator as a drive source is illustrated as an example of the configuration of the vehicle 2. However, the vehicle 2 may be configured to have a plurality of speed reduction units, and is limited to the hybrid vehicle. Not. For example, the vehicle 2 may be any type of vehicle such as a conventional vehicle using only an engine as a drive source, or an EV vehicle using only a motor generator as a drive source. When the vehicle 2 is a conveyor vehicle, as a plurality of deceleration means, for example, fuel cut control for stopping fuel supply to the engine, coasting control for cutting off power transmission between the engine and driving wheels, engine brake, hydraulic pressure Brake can be included.

  In the above-described embodiment, the configuration in which the approach of the inter-vehicle distance with the preceding vehicle traveling in front of the traveling path of the vehicle 2 is exemplified, but the object that the vehicle 2 avoids approaching is in front of the traveling path of the vehicle 2. It may be a predecessor that exists, and may be an obstacle other than a car or a pedestrian.

1 driving support device 2 vehicle 6 ECU
61 Leading vehicle detection unit 62 Speed pattern generation unit 63 Support state selection unit 64 Driving support control unit

Claims (3)

A driving support device that generates a speed pattern according to a travel route of a vehicle and performs driving support based on the speed pattern,
The vehicle has a plurality of deceleration means;
When approaching the preceding body is predicted when the distance between the preceding body and the vehicle existing in front of the traveling path of the vehicle is equal to or less than a predetermined value, the approach can be avoided among the plurality of deceleration means. Change the driving support based on the deceleration speed pattern when the selected deceleration means is selected ,
Estimating the speed pattern of the preceding body based on the inter-vehicle distance and relative speed with the preceding body,
Based on the current position and current speed of the vehicle and deceleration generated by the plurality of deceleration units, the deceleration rate pattern when the plurality of deceleration units are executed is estimated,
The speed pattern of the preceding body and the deceleration speed pattern are compared to estimate the distance between the preceding body and the vehicle after a predetermined time from the current time, and the estimated value of the distance is greater than or equal to a predetermined value And determining that the approach to the preceding body can be avoided .   2. The driving support device according to claim 1, wherein when there are a plurality of speed reduction means that can avoid the approach, the speed reduction means that requires the least power for deceleration is selected. After changing to driving assistance based on the deceleration speed pattern when the selected deceleration means is executed, driving assistance for urging the driver to accelerate is performed when the average vehicle speed of the vehicle is a predetermined value or less. The driving support device according to claim 1 or 2 .

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