JP5677804B2 - Fuel-saving driving system - Google Patents

Description

  The present invention relates to a fuel-saving driving system for a vehicle.

  2. Description of the Related Art Conventionally, there is known a system that determines the state of a road on which a vehicle travels and performs fuel-saving driving according to the road state.

  Patent Document 1 discloses a travel pattern generation device that acquires road information of a route on which a vehicle is to travel, generates a travel pattern, and performs fuel-saving driving according to the generated travel pattern. In this travel pattern generation device, fuel-saving driving is performed based on a travel pattern that is generated by predicting the number of stops of a vehicle from the position of a traffic light or the number of times of a right turn across an opposite lane.

JP 2001-183150 A

  However, in the travel pattern generation device of Patent Literature 1, fuel consumption is reduced by predicting the acceleration / deceleration of the vehicle based on the position where the vehicle is predicted to stop. Therefore, a difference may occur between the generated traveling pattern and the actual traveling state of the vehicle.

  The present invention has been made in view of the above problems, and an object thereof is to improve the accuracy of fuel-saving driving in a vehicle.

The present invention includes a position information acquisition unit that acquires position information of a vehicle, a brake determination unit that determines that the braking device of the vehicle is operating, and a braking history that the braking device of the vehicle has operated in the past. A database stored together with the position information, a fuel limiting unit for limiting the amount of fuel supplied to the engine of the vehicle based on the braking history stored in the database, and the vehicle acquired by the position information acquiring unit A braking history acquisition unit that acquires a braking history on the course of the vehicle based on the position information from the database, and a fuel that calculates a fuel restriction start position of the vehicle based on the braking history acquired by the braking history acquisition unit with a restriction start position calculation unit, wherein the fuel limiting portion, when the vehicle reaches the fuel restriction start position, that you limit the amount of fuel supplied to the engine And butterflies.

  According to the present invention, since the amount of fuel supplied to the engine is limited based on the braking history of the braking device stored in the braking history storage unit, it is possible to perform fuel-saving driving in accordance with the actual running state of the vehicle. Is possible. Therefore, the accuracy of fuel-saving driving in the vehicle can be improved.

It is a lineblock diagram of a fuel-saving driving system concerning an embodiment of the invention. It is a block diagram of the fuel-saving driving system which concerns on other embodiment. It is a flowchart figure of a braking history database creation apparatus. It is a figure which shows an example of the database produced by the braking history database creation apparatus. It is a flowchart figure of the fuel-saving driving system concerning an embodiment of the invention. It is a figure explaining the data which the fuel-saving driving system read from the database. It is a figure which shows an example of the map of the speed and acceleration for calculating a fuel restriction start position. It is a figure explaining a fuel restriction start position.

  Hereinafter, a fuel-saving driving system 100 according to an embodiment of the present invention will be described with reference to the drawings.

  First, the configuration of the fuel-saving driving system 100 will be described with reference to FIG.

  The fuel-saving driving system 100 is mounted on a vehicle (not shown), suppresses the fuel consumption of the running vehicle, and performs fuel-saving driving. The fuel-saving operation system 100 is connected to an engine ECU (Electronic Control Unit) 101 that executes engine control, and can adjust the amount of fuel supplied to the engine. The fuel-saving driving system 100 suppresses fuel consumption by performing coasting traveling by limiting the amount of fuel supplied to the engine based on the position where the braking device has been operated in past traveling.

  A vehicle equipped with the fuel-saving driving system 100 includes a vehicle speed sensor 1 that detects the speed of the vehicle, an auxiliary brake sensor 2 that detects the operating state of the auxiliary brake, and a service brake sensor 3 that detects the operating state of the service brake. Is provided. You may detect the operating state of each brake from ECU which controls each brake, without providing the auxiliary brake sensor 2 and the service brake sensor 3 independently.

  The vehicle speed sensor 1 is a sensor that is mounted on a vehicle and detects the rotation of the output shaft of the transmission.

  The auxiliary brake sensor 2 is a sensor that detects an operating state of an auxiliary brake such as an exhaust brake or a retarder of the vehicle.

  The service brake sensor 3 is a sensor that detects an operating state of a service brake (main brake) of the vehicle. Here, the service brake and the auxiliary brake are collectively referred to as a braking device.

  The vehicle also includes an engine fuel flow sensor 4 that detects the amount of fuel supplied to the engine, an engine load sensor 5 that detects engine load, an acceleration sensor 6 that detects vehicle acceleration, and vehicle position information. And a GPS (Global Positioning System) sensor 7 for detection. The fuel supply amount and the engine load may be detected by the engine ECU 101 without providing the fuel flow sensor 4 and the engine load sensor 5 independently. Further, the acceleration / deceleration of the vehicle may be calculated based on the change in the vehicle speed detected by the vehicle speed sensor 1 without providing the acceleration sensor 6 independently.

  The GPS sensor 7 acquires the absolute position information of the vehicle from one or a plurality of GPS satellites (not shown). The position information here is latitude and longitude on the earth. As a GPS sensor, you may use GPS which the car navigation system mounted in a vehicle has.

  The GPS sensor 7 detects the number of GPS satellites that can receive radio waves. When the number of GPS satellites is plural, the accuracy of the position information is improved. Therefore, the position information may be output only when the number of GPS satellites capable of receiving radio waves is equal to or greater than a predetermined number. .

  The fuel-saving driving system 100 includes a controller 10 that performs fuel-saving driving control, and a storage device 20 that stores a braking history database 21 of the braking device together with vehicle position information.

  The controller 10 is composed of a microcomputer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an I / O interface (input / output interface). The RAM stores data in the processing of the CPU, the ROM stores a control program of the CPU in advance, and the I / O interface is used for input / output of information with the connected device. Control of the fuel-saving driving system 100 is realized by operating the CPU, RAM, and the like according to a program stored in the ROM.

  The controller 10 is connected to the vehicle speed sensor 1, auxiliary brake sensor 2, service brake sensor 3, fuel flow sensor 4, engine load sensor 5, acceleration sensor 6, and GPS sensor 7 via an I / O interface. Receive signals from ~ 7. The controller 10 is connected to the engine ECU 101 via an I / O interface, and transmits a command for limiting fuel supplied to the engine.

  The controller 10 includes a braking history database creation device 200 that creates in the storage device 20 a database 21 in which braking history of the braking device is stored together with vehicle position information.

  Hereinafter, the braking history database creation device 200 will be described.

  The braking history database creation device 200 creates a braking history database 21 that is used when the fuel-saving driving system 100 performs fuel-saving driving. The database 21 created by the braking history database creation device 200 is, for example, as shown in FIG.

  The braking history database creation device 200 is communicably connected to the storage device 20, and can transmit and receive data to and from each other. The storage device 20 stores a database 21 such as braking history along with vehicle position information. The storage device 20 is configured by a hard disk, a flash memory, or the like.

  The braking history database creation device 200 includes a position information acquisition unit 11 that acquires vehicle position information, and a braking determination unit 12 that determines that the braking device is operating.

  The position information acquisition unit 11 acquires the current absolute position information of the vehicle detected by the GPS sensor 7. The position information acquired by the position information acquisition unit 11 is transmitted to the storage device 20 and stored in the database 21.

  The braking determination unit 12 determines the braking state of the vehicle based on data detected by the vehicle speed sensor 1, the auxiliary brake sensor 2, the service brake sensor 3, and the acceleration sensor 6. Specifically, the braking determination unit 12 determines that the service brake or auxiliary brake of the vehicle has been applied for a certain period of time, the service brake has been applied, and the speed at which the vehicle has decelerated is greater than or equal to a predetermined deceleration width, and The brake device is determined to be operating when a service brake is applied and any one of the three conditions that the vehicle deceleration is equal to or greater than a predetermined value is satisfied. Accordingly, it can be determined that the braking device is reliably operated to the extent that the braking device is operated by the driver and the vehicle decelerates.

  The braking information of the braking device determined by the braking determination unit 12 is transmitted to the storage device 20 as a braking history together with the position information acquired by the position information acquisition unit 11 and stored in the database 21.

  In addition, the braking history database creation device 200 is configured so that the cumulative braking number obtained by integrating the number of times the braking device has been operated in the past at the same point of the vehicle and the point at which the vehicle passes through the same point at the end. The number of times of continuous braking in which the braking device has been operated continuously is transmitted to the storage device 20 and stored in the database 21.

  The accumulated braking number is the accumulated number of times that the braking device is operated when the vehicle travels at the same point. The accumulated number of times of braking is accumulated one by one every time the braking device is operated at that point. When the cumulative number of braking times increases, it is predicted that the brake device is likely to operate at that point.

  The number of times of continuous braking is the number of times that the braking device is operated continuously every time the vehicle passes through the same point until the vehicle passes through the same point. The number of continuous brakings is accumulated one by one every time the braking device is operated at that point, but is reset to zero when the braking device has never been operated at that point. Therefore, if the number of times of continuous braking is used, it is predicted that the braking device will surely operate at that point. Further, when the number of continuous braking is reset to zero, it is predicted that the road condition has changed like a point where a signal has been installed in the past but has now been removed.

  Further, the braking history database creation device 200 further transmits the vehicle speed of the vehicle at that point and the deceleration applied to the vehicle during deceleration to the storage device 20 and stores it in the database 21.

  By configuring the braking history database creating apparatus 200 as described above, the database 21 in which data such as the braking history of the vehicle is stored together with the position information is created.

  The controller 10 includes a braking history acquisition unit 15 that acquires data such as a braking history from the database 21, a fuel limit start position calculation unit 16 that calculates a fuel limit start position, and an engine based on the braking history stored in the database 21. And a fuel restricting unit 17 for restricting the amount of fuel supplied to the fuel.

  The braking history acquisition unit 15 acquires data such as a braking history on the course of the vehicle from the database 21 based on the vehicle position information acquired by the position information acquisition unit 11. The data acquired by the braking history acquisition unit 15 is, for example, as shown in FIG.

  The fuel restriction start position calculation unit 16 calculates a fuel restriction start position for starting restriction of the amount of fuel supplied to the vehicle based on data such as the braking history acquired by the braking history acquisition unit 15. The fuel limit start position calculation unit 16 calculates a fuel limit start position based on a map created in accordance with the vehicle speed and deceleration as shown in FIG.

  When the vehicle reaches the fuel limit start position calculated by the fuel limit start position calculation unit 16, the fuel limit unit 17 limits the amount of fuel supplied to the engine. The fuel limiting unit 17 limits the amount of fuel supplied to the engine when the cumulative number of brakings is equal to or greater than a predetermined number. Further, the fuel restriction unit 17 restricts the amount of fuel supplied to the engine when the number of times of continuous braking is equal to or greater than a predetermined number.

  As shown in FIG. 2, in the case of a vehicle including an in-vehicle network 30 such as CAN (Controller Area Network) communication, the controller 10, the engine ECU 101, and the like are connected via the in-vehicle network 30 so that communication can be performed alternately. Connected.

  Hereinafter, the operation of the fuel-saving driving system 100 will be described with reference to FIGS. 3 to 8.

  First, the operation of the braking history database creation device 200 will be described with reference to FIGS. 3 and 4.

  In step 301 in the flowchart of FIG. 3, the position information of the vehicle detected by the GPS sensor 7 is read by the position information acquisition unit 11.

  In step 302, vehicle information detected by the vehicle speed sensor 1, the auxiliary brake sensor 2, the service brake sensor 3, the fuel flow sensor 4, the engine load sensor 5, and the acceleration sensor 6 is read.

In step 303, the average vehicle speed V _ave (m / s) is calculated. Specifically, first, the past vehicle speed data stored at the current position of the vehicle is read from the database 21 of the storage device 20. And the average value of the vehicle speed data memorize | stored as a statistical value of vehicle speed until now is calculated, and it is set as average vehicle speed _Vave .

  In step 304, the braking determination unit 12 determines whether or not the vehicle braking device is operating. If it is determined in step 304 that the braking device is operating, the process proceeds to step 305 and the average deceleration is calculated. On the other hand, if it is determined in step 304 that the braking device is not operating, the process proceeds to step 306.

In step 305, the average deceleration G _ave (m / s) of the vehicle is calculated. Specifically, first, the vehicle deceleration G _n (m / s ² ) in the current braking is calculated. The deceleration G _n is determined by G _n = ΔV / T based on the change amount ΔV (m / s) of the vehicle speed, which is the speed range decelerated in the current braking, and the time T (s) during which the braking device has been operating. Calculated. The vehicle deceleration detected by the acceleration sensor 6 may be used as the vehicle deceleration _Gn .

Subsequently, the average deceleration _Gave is calculated. The average deceleration G _ave is an average deceleration G _ave (n−1) (m / s ² ) stored in the database 21 and an accumulated braking number N (n−1) (times) stored in the database 21. , G _ave = {G _ave (n−1) × N (n−1) + G _n from the deceleration G _n (m / s ² ) in the current braking and the total number of brakes N (n) (times) } / N (n).

In step 306, the total braking number N (n) and the continuous braking number N _C (n) are calculated. When the braking device is activated, the cumulative braking number N (n) is calculated from the cumulative braking number N (n−1) stored in the storage device 20 by N (n) = N (n−1) +1. Is done. Similarly, the continuous braking number N _C (n) is calculated from the continuous braking number N _C (n−1) stored in the storage device 20 by N _C (n) = N _C (n−1) +1. . That is, when the braking device is activated, the accumulated braking number N (n) and the continuous braking number N _C (n) at that point are accumulated one by one.

On the other hand, when the braking device does not operate, the cumulative braking number N (n) is not changed, and the continuous braking number N _C (n) is reset to zero.

In step 307, the absolute position information (latitude, longitude) of the vehicle, average deceleration G _ave , cumulative braking number N (n), continuous braking number N _C (n), vehicle speed after deceleration, and average vehicle speed V _ave Is stored in the database 21 of the storage device 20.

  By periodically repeating the processes in steps 301 to 307 described above, the storage device 20 creates the braking history database 21 as shown in FIG. This database 21 is created based on the history of actual vehicle travel. Therefore, since the database 21 conforms to the actual traveling of the vehicle, if the fuel-saving driving is performed based on the database 21, the accuracy of the fuel-saving driving can be improved.

  The database 21 is updated by the vehicle traveling a plurality of times on the same route, and learns itself. Therefore, the greater the number of times the vehicle travels on the same route, the more reliable the database 21 is.

  In the braking history database creation device 200, data of a point where the braking device is not operated is also stored in the database 21, but if only data of a point where the braking device is operated is stored in the database 21, the database 21 is stored. The capacity of can be suppressed.

  The database 21 may be transmitted to a data center outside the vehicle via a communication device such as a telematics system mounted on the vehicle so that the database 21 of a plurality of vehicles can be shared. In this case, by sharing the database 21 of a plurality of vehicles, it is possible to efficiently collect and use braking information.

  Next, the operation of the fuel-saving driving system 100 will be described with reference to FIGS.

  In step 501 in the flowchart of FIG. 5, the vehicle position information detected by the GPS sensor 7 is read by the position information acquisition unit 11.

  In step 502, vehicle information detected by the vehicle speed sensor 1, the fuel flow sensor 4, the engine load sensor 5, and the acceleration sensor 6 is read.

  In step 503, the braking history acquisition unit 15 reads data such as the braking history of the braking device from the database 21 of the storage device 20. In step 503, data such as a braking history in the traveling direction of the vehicle is read from the position and traveling direction of the vehicle. For example, data in a circular range having a predetermined radius from the current position of the vehicle, or data such as braking history on the road in the traveling direction are read in comparison with map data.

  The read data includes, for example, a history of operating the braking device in the traveling direction of the vehicle as shown in FIG. In FIG. 6, the horizontal axis represents the distance traveled by the vehicle (m), and the vertical axis represents the braking history, the average vehicle speed (m / s), and the number of continuous braking.

  In step 504, it is determined whether or not there is a braking history in which the braking device is activated in the read data. If it is determined in step 504 that there is a braking history as in the case where the data shown in FIG. 6 is read, the process proceeds to step 505. If it is determined that there is no braking history, the process returns to step 501. To do.

In step 505, it is determined whether or not the number of continuous braking times N _C is equal to or greater than a predetermined number. If it is determined in step 505 that the number of consecutive braking times N _C is equal to or greater than the predetermined number, the process proceeds to step 506. On the other hand, in step 505, when the continuous number of braking N _C is determined to less than the predetermined number of times, the process returns to step 501.

When the number of times of continuous braking N _C is zero, there is a possibility that the road condition has changed, for example, the signal has been removed as described above. By determining whether or not the number of times of continuous braking N _C is equal to or greater than a predetermined number, it is possible to cope with changes in road conditions.

Note that it may be determined whether the cumulative braking number N is equal to or greater than a predetermined number, instead of the continuous braking number N _C. In this case, when the cumulative braking number N is equal to or greater than the predetermined number, the process proceeds to step 506. Thus, for example, fuel-saving operation is executed by data with low certainty, for example, the amount of fuel supplied to the engine is limited based on the fact that the braking device has been activated when this point is passed only once last time. Can be prevented.

Further, it may be determined whether or not the cumulative braking number N is equal to or greater than a predetermined number, and whether or not the continuous braking number N _C is equal to or greater than a predetermined number. In this case, if the integrated braking number N is equal to or greater than the predetermined number and the continuous braking number N _C is equal to or greater than the predetermined number, the process proceeds to step 506. Thereby, the certainty of data is improved, and the accuracy of fuel-saving driving is further improved.

  In step 506, the fuel limit start position calculation unit 16 calculates a fuel limit start position for starting the limit of the amount of fuel supplied to the engine. The fuel restriction start position is determined based on a map created corresponding to the vehicle speed and deceleration as shown in FIG.

As shown in FIG. 7, in the map, the horizontal axis is the speed change amount V _d (km / h) between the current vehicle speed and the average vehicle speed after deceleration, and the vertical axis is the deceleration stored in the database 21. (M / s ² ). Each numerical value in the map is the fuel limit distance X (m) from the point where the braking device operates to the fuel limit start position. In step 506, the fuel limit distance X (m) is obtained based on this map. The fuel limit distance X is set to a longer distance as the speed change amount V _d increases and the deceleration increases.

  The fuel restriction start position is set as shown in FIG. In FIG. 8, the horizontal axis represents the distance (m) traveled by the vehicle, and the vertical axis represents the braking history and the fuel restriction start position. As shown in FIG. 8, the fuel limit start position is set in front of the fuel limit distance X from the point where the braking history exists.

For example, based on the data such as the braking history shown in FIG. 6, consider a case where the vehicle is currently traveling at 30 (km / h) and has a temporary stop in front and stops. When there is a braking history before the temporary stop position and the average vehicle speed after deceleration read from the database 21 is (0 km / h), the speed change amount V _d is 30−0 = 30 (km / h). It is. If the average deceleration G _ave in the braking history just before the temporary stop position read from the database 21 is 2.0 (m / s ² ), the fuel limit distance X = 60 (m ) Is required. Thus, when the vehicle reaches a point 60 (m) before the point where there is a braking history before the temporary stop position, the fuel supply amount restriction to the engine is started.

  In step 507, it is determined whether or not the vehicle has reached the fuel limit start position. If it is determined in step 507 that the vehicle has reached the fuel restriction start position, the process proceeds to step 508, where fuel restriction is executed. On the other hand, if it is determined in step 507 that the vehicle has not reached the fuel limit start position, the process returns to step 501.

  In step 508, fuel restriction is performed to limit the amount of fuel supplied to the engine. As a result, the amount of fuel supply can be limited just before the position where the vehicle braking device actually operates, and coasting can be performed. Therefore, since it is possible to perform fuel-saving driving according to the actual running state of the vehicle, the accuracy of fuel-saving driving in the vehicle can be improved.

  In addition, by limiting the fuel supply amount before the position where the braking device operates, deceleration can be started by the engine brake from the position before the position where the braking device operates. Therefore, it is possible to prevent the vehicle from suddenly braking and to avoid a dangerous state.

  In the fuel restriction, the control is performed so that the fuel restriction amount is increased, that is, the fuel supply amount is decreased as the fuel restriction start position is approached to a point having a braking history. As a result, the amount of fuel supplied to the engine is gradually limited, so that the driver of the vehicle is prevented from feeling uncomfortable.

  Since fuel-saving driving only needs to be performed, fuel limitation is not performed, but vehicle speed limitation for limiting vehicle speed or acceleration limitation for limiting vehicle acceleration is performed. Good.

  Further, for example, when the driver tries to accelerate by depressing the accelerator while the fuel-saving driving is being executed, the fuel-saving driving is canceled. As described above, when the driver performs an operation contrary to the fuel-saving driving, the fuel-saving driving is canceled to prevent the driver from feeling uncomfortable.

  According to the above embodiment, the following effects are produced.

  The database 21 created based on the history of actual traveling of the vehicle stores data such as the braking history of the actual operation of the braking device. Since this database 21 conforms to the actual traveling of the vehicle, if fuel-saving driving is performed based on the database 21, the accuracy of fuel-saving driving can be improved.

  Further, by restricting the amount of fuel supplied to the engine based on data such as the braking history of the braking device stored in the database 21 of the storage device 20, the fuel is placed before the position where the braking device of the vehicle actually operates. It is possible to carry out coasting travel by limiting the amount of supply. Therefore, it is possible to perform fuel-saving driving in accordance with the actual traveling state of the vehicle. Therefore, it is possible to improve the accuracy of fuel-saving driving in the vehicle.

  The present invention is not limited to the above-described embodiment, and it is obvious that various modifications can be made within the scope of the technical idea.

  The fuel-saving driving system of the present invention can be used for promoting fuel-saving driving in a vehicle.

DESCRIPTION OF SYMBOLS 100 Fuel-saving driving system 200 Brake history database creation apparatus 1 Vehicle speed sensor 2 Auxiliary brake sensor 3 Service brake sensor 4 Fuel flow sensor 5 Engine load sensor 6 Acceleration sensor 7 GPS sensor 10 Controller 11 Position information acquisition part 12 Brake determination part 15 Brake history Acquisition unit 16 Fuel limit start position calculation unit 17 Fuel limit unit 20 Storage device 21 Database 101 Engine ECU

Claims (4)

A position information acquisition unit for acquiring position information of the vehicle;
A braking determination unit for determining that the braking device of the vehicle is operating;
A database in which a braking history in which the braking device of the vehicle has been operated in the past is stored together with the position information;
A fuel limiter that limits the amount of fuel supplied to the engine of the vehicle based on the braking history stored in the database ;
A braking history acquisition unit that acquires a braking history on the course of the vehicle from the database based on the position information of the vehicle acquired by the position information acquisition unit;
A fuel limit start position calculation unit that calculates a fuel limit start position of the vehicle based on the braking history acquired by the braking history acquisition unit,
The fuel limiting portion, when the vehicle reaches the fuel restriction start position, fuel-saving driving system characterized that you limit the amount of fuel supplied to said engine. The database further stores the speed of the vehicle and the deceleration of the vehicle during braking,
2. The fuel-saving driving system according to claim 1 , wherein the fuel restriction start position is determined based on a map created corresponding to a speed at which the vehicle decelerates and a deceleration of the vehicle. The database further stores the cumulative number of braking times obtained by integrating the number of times the braking device has been operated in the past at the same point,
3. The fuel-saving driving system according to claim 1, wherein the fuel restriction unit restricts a fuel supply amount to the engine when the cumulative number of brakings is equal to or greater than a predetermined number. The database further stores the number of times of continuous braking in which the braking device is continuously operated at the point where the vehicle has finally passed the same point,
The fuel limiting portion, when the continuous number of braking is above a predetermined number of times, saving according to claim 1, any one of 3, characterized in that to limit the amount of fuel supplied to the engine Fuel efficient driving system.

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