JP4615369B2 - Vehicle travel support device - Google Patents

Description

  The present invention relates to a vehicle travel support device that learns a target travel path on which a host vehicle should travel based on a travel locus generated by the travel of the host vehicle.

  In recent years, GPS (Global Positioning System) that detects the position of a vehicle based on position data obtained from an artificial satellite has been widely used in navigation devices for vehicles, and based on the vehicle position information detected by this GPS. Various techniques for running control have been proposed and put into practical use.

For example, in Japanese Patent Laid-Open No. 2001-255937, in a vehicle-mounted navigation system, a driver sets a destination, and automatic steering or automatic acceleration / deceleration is performed using a travel locus to the destination generated by the navigation system as a target travel path. Discloses a technique for automatically controlling the own vehicle.
JP 2001-255937 A

  In the technique disclosed in the above-described document, the travel path (target travel path) on which the host vehicle should travel is unambiguous from the travel trajectory obtained by a single travel (a node sequence composed of a plurality of node points). Therefore, the driver must first input accurate driving data to the navigation system.

  However, once the target travel path of the host vehicle has been established by a single run, if you want to change some travel positions from the center of the vehicle width to the left side, for example, then re-start all travel data from the beginning. It will be necessary to input and generate a travel locus. As a result, there is a problem that the own vehicle has to be repeatedly tested several times before a satisfactory target traveling path is secured, which is inconvenient.

  In order to cope with this, it may be possible to secure the optimum traveling position by traveling the same route a plurality of times, comparing and learning the node points obtained for each traveling.

  However, since the sampling interval time obtained from the GPS is constant, the node points set in time series on the map indicate different passing points depending on the vehicle speed at that time. In other words, even when moving on the same road, if the speed changes, the distance between the node points will be different for each run.

  As a result, when the node points for each run are simply compared according to time series, if the speed difference is large, the distance difference between each node point to be compared becomes large. Therefore, the travel locus (node sequence) obtained by learning The target travel path set based on the vehicle cannot faithfully reproduce the travel locus desired by the driver. For this reason, there is an inconvenience that the driver feels uncomfortable when the vehicle is driven by the automatic steering control along the set target traveling path.

  SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a vehicle travel support device that can construct a target traveling path along a travel locus desired by a driver relatively easily and is easy to use.

Driving support apparatus for a vehicle according to the present invention for achieving the above object, the installation position is specified, the reference station to determine the correction information by correcting the information from the GPS satellites on the basis of the said installation position, the vehicle when a mobile station with mounted calculates the vehicle position based on information from the GPS satellites, the communication between the reference station and the mobile station has been established, the from the correction information and the vehicle position of the reference station Vehicle position calculation means for correcting and calculating the vehicle position, and a storage means for storing a travel locus in which the mobile station guides the vehicle to a destination within a communicable area of the reference station in a node sequence; and the GPS A node point to the destination is set based on the position information transmitted from the satellite at regular intervals and the information transmitted from the reference station, and the node point is set from the set of node points. Control means for generating a node sequence, and the control means sets a node sequence having a smaller total number of node points as a basic node sequence based on the two node sequences in the same route, Select the node point with the smallest distance difference by comparing the node point of the node sequence with the node point of the other node sequence, and select for each node point of the basic node sequence based on each selected node point An average value with the node point is calculated, and a node sequence of a set including the average value is learned as a travel locus for guiding the vehicle to a destination .

  According to the present invention, since one node train is generated by traveling the same traveling path a plurality of times, there is no need to re-enter traveling data repeatedly until a desired target traveling path is obtained. The target travel path along the travel locus desired by the driver can be constructed relatively easily and is easy to use.

  In particular, it is possible to learn node points even for node sequences set with different distance intervals, and a target traveling path can be constructed relatively easily.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an overall configuration diagram of a vehicle travel support apparatus.

  Reference numeral 1 in FIG. 1 denotes a vehicle such as an automobile (own vehicle). The own vehicle 1 is equipped with a travel control device 2 as a mobile station that performs control using RTK (Real-Time Kinematic) -GPS. Yes. The RTK-GPS in this embodiment is configured so that information from an artificial satellite (GPS satellite) 3 orbiting the earth (data such as satellite orbit information necessary for positioning calculation) is transmitted to the reference station 4 and the host vehicle 1. It is received by both the travel control device 2 provided.

  The reference station 4 includes a GPS antenna 4a, a GPS receiver 4b, a wireless device 4c, and the like, and is installed at a position adjacent to the parking space of the host vehicle 1, for example. The installation position of the reference station 4 is accurately specified in advance. Based on the installation position, the phase information of the radio wave from the GPS satellite 3 observed by itself, the pseudo distance, and the position information of the reference station 4 (self-position information) Correction information such as a certain position coordinate, error correction amount, pseudo distance correction amount, and coordinate value is created, and this information is transmitted to the traveling control device 2 mounted on the host vehicle 1 via the wireless device 4c.

  The wireless device 4c is an access point that transmits and receives based on a wireless local area network (LAN) based on a standard such as IEEE 802.11a / b / g, for example, and maintains SSID (Service Set ID), WEP (WEP) to maintain communication security. Wired Equivalent Privacy (MAC) key and MAC (Media Access Control) address authentication settings are specially made. As shown in FIG. 3, in this embodiment, a radius of about 50 to 100 m is set as a communicable area with the wireless device 4c as the center.

  The own vehicle 1 is equipped with a radio device 5c that communicates with the GPS antenna 5a, the GPS receiver 5b, and the reference station 4. When the host vehicle 1 enters the communicable area with the reference station 4 and communication with the reference station 4 is established, the GPS receiver 5b is configured such as an error correction amount, a pseudo distance correction amount, a coordinate value, and the like transmitted from the reference station 4. Data (data received by the wireless device 5c) and information from the GPS satellite 3 received by the host vehicle 1 are compared and analyzed, and the host vehicle position (coordinate value) is detected with an error of about 1 to 5 cm, for example. .

  The travel control device 2 includes a control device 8, and the above-described GPS receiver 5 b and the obstacle recognition unit 7 are connected to the control device 8. A stereo camera 6 is connected to the obstacle recognizing unit 7, and the road environment ahead is examined based on an image captured by the stereo camera 6 to recognize a front obstacle. The vehicle position information is input from the GPS receiver 5 b to the control device 8, and information indicating the presence or absence of a front obstacle is input from the obstacle recognition unit 7.

  The stereo camera 6 is composed of a pair of (left and right) cameras using, for example, a solid-state image sensor such as a charge coupled device (CCD) as a stereo optical system. Is input to the obstacle recognition unit 7.

  The control device 8 includes a GPS receiver 5b, an obstacle recognition unit 7, a vehicle speed sensor 9 for detecting the vehicle speed V, sensors such as a handle angle sensor 10 for detecting the handle angle θH, and a main switch for automatic steering control. 11, switches such as a brake pedal switch 12, an accelerator pedal switch 13, and an ignition switch (not shown) are connected.

  The control device 8 is provided with readable / writable storage means such as an HDD, flash memory, CD, DVD, etc., such as a learning node string γ (described later) generated in an area where communication with the reference station 4 is possible. Map information is stored. The map information read from the storage means is appropriately displayed on, for example, a liquid crystal display 14 as a display means provided on the dashboard, and is guided by the position of the reference station 4, the current position of the host vehicle 1, and automatic piloting. A target travel path, a travel locus (node row) generated in the past, or a currently generated travel locus (node row) is displayed.

  The control device 8 is connected to an electric throttle valve control device 15, a brake control device 16, and an electric power steering control device 17 as actuators that execute automatic steering control. When the own vehicle 1 enters the communicable area and communication with the reference station 4 is established, the control device 8 substantially matches the traveling locus on the map data created in the past. If there is, the autopilot control is performed with the coincident traveling path as the target traveling path.

  Specifically, vehicle speed control is performed to maintain the target vehicle speed by controlling the opening degree of the throttle valve 18 by a drive signal from the electric throttle valve control device 15, and when the target vehicle speed is greatly reduced, brake control is performed. The brake is actuated by a drive signal from the device 16 to perform deceleration control. Further, the electric power steering control device 17 is driven to perform steering control so that the host vehicle 1 travels along the target traveling path.

  This target traveling path is generated based on a learning node sequence γ learned by the driver traveling on the same path a plurality of times. Specifically, the learning node sequence γ is generated according to a learning node sequence generation routine shown in FIG.

  This routine is executed every set calculation cycle after turning on an ignition switch (not shown). First, in step S1, the host vehicle 1 on the return path waits until it enters the communicable area shown in FIG. Then, when the own vehicle 1 enters the communicable area (point A in FIG. 4) and communication between the control device 8 and the reference station 4 is established via the wireless devices 4c and 5c, the process proceeds to step S2, and the travel data To get. The travel data is converted into the XY coordinate axis format on the map according to the position information (latitude, longitude) transmitted from the GPS satellite 3 at regular intervals, and node points are set. Vehicle information (vehicle speed V, steering wheel angle θH, etc.) when the position information is received is linked to the node point and stored.

  Next, the process proceeds to step S3, where it is determined whether or not the ignition switch is turned off. When the ignition switch is turned on, the travel data of the host vehicle 1 is continuously obtained until it is turned off.

  When the ignition switch is turned off, it is determined that the host vehicle 1 has been stored in the parking space (point B in FIG. 3), which is the destination, and the process proceeds to step S4, where the number of nodes αn of the node sequence α generated last time is determined. And the number of nodes βn of the node sequence β generated this time are compared. As shown in FIG. 4, the node sequences α and β are sets of node points that are set at regular intervals and displayed in the XY coordinate axis format on the map. The total number is the number of nodes αn, βn. At the time of the first routine execution after the base station 4 is installed near the parking space, the previous node sequence α does not exist, so the routine of step S4 transition is not executed, and based on the currently set node point. After generating the node sequence α, the routine is exited to prepare for the next routine execution.

  In the following description, a case where the second routine is executed for convenience will be described. Accordingly, it is assumed that the data of the node sequence α based on the node points set at the time of the first routine execution is already stored in the control device 8.

  As described above, the node point is set according to the position information transmitted from the GPS satellite 3 at regular intervals. Accordingly, even when traveling on the same route (points A to B in this embodiment), the total number of node points decreases if the vehicle speed at that time is high, and the total number of node points increases if the vehicle speed is low. .

  In step S4, the number of nodes αn of the previous node sequence α is compared with the number of nodes βn of the current node sequence β, and the absolute value (| αn−βn |) of the difference is equal to or less than the set number Kn (| αn -Βn | ≦ Kn), the process proceeds to step S5. If the set number Kn is exceeded (| αn−βn |> Kn), the routine is terminated.

  That is, if the absolute value (| αn−βn |) of the difference between the number of nodes αn of the previous node sequence α and the number of nodes βn of the current node sequence β exceeds the set number Kn, the previous node sequence α The difference between the vehicle speed V when generating the current node sequence β and the vehicle speed V when generating the current node sequence β is large, and the error is large when the node points of both node sequences α and β are compared in the data series (distance series). So, just exit the routine. In this case, both the previous and current generated node sequences α and β may be discarded, and a new node sequence may be generated next time. Alternatively, the node sequences α and β with the smaller number of nodes αn and βn may be left and the node sequences α and β with the larger number of nodes may be discarded.

  When it is determined that | αn−βn | ≦ Kn and the process proceeds to step S5, the node sequence α, β having the smaller number of nodes αn, βn is set as the basic node sequence κ (κ ← min (αn, βn). ). In the following description, the node sequence α is described as a basic node sequence κ for convenience.

  Next, the process proceeds to step S6, in which the node points of the respective node sequences α and β are converted into X-axis coordinates and distance series data obtained by time-integrating time series speed information and expressed in the X-distance coordinate format (FIG. 5 (a)).

  Next, the process proceeds to step S7, with the node points of the basic node sequence κ as a reference, the node points of the other node sequence β are compared in the distance series, and the node point having the smallest distance difference from the node points of the node sequence β is The selection is made as shown in FIG.

  That is, the number of nodes αn. A node having a smaller βn is set as a basic node sequence κ (node sequence α in this embodiment), and a node point of a node sequence having a large number of nodes is selected on the basis of the node points of the basic node sequence κ. The calculation load is reduced, and the calculation time can be shortened.

  Thereafter, in step S8, an average value of the node points of the basic node sequence κ and the corresponding node points of the node sequence β is calculated, and the node points of the basic node sequence κ are learned. The calculation method of the average value may be a simple average, but may be a weighted average weighted in a predetermined manner.

  Then, the process proceeds to step S9, where the node points of the learned basic node sequence κ and the node points of the node sequence β that are not used for learning are integrated into this basic node sequence κ, and the learned node sequence γ is shown in FIG. After generating and storing in memory, the routine is terminated.

  As described above, in this embodiment, the two node sequences α and β are converted into distance series, the smaller number of nodes αn and βn is set as the basic node sequence κ, and the node point of the basic node sequence κ is used as a reference. The node point having the smallest distance difference from the node point of the other node row is selected from the node points of the other node row, and learning is performed by averaging both node points. It is possible to set a learning node sequence γ that is not affected by variations in the travel locus (node sequence).

  In the case of automatic steering control, after the main switch 11 for automatic steering control is turned on, when the own vehicle 1 enters the communicable area and communication with the reference station 4 is established, the current position of the own vehicle 1 is displayed on the map. If the learning node sequence γ (traveling locus) generated on the data is substantially the same, a target traveling path is generated based on the learning node array γ, and the host vehicle 1 is automatically steered along the target traveling path. Control.

  In this case, in the learning node sequence γ, node points that have not been used for learning of the node sequence (β in this embodiment) are integrated as interpolation values of the learning data, and therefore based on only the node points obtained by learning. Compared to the node sequence generated in this way, the target traveling path that the host vehicle 1 should travel can be reproduced more faithfully.

  In this embodiment, the learning node sequence γ is set by one learning, but the learning node sequence γ may be generated by the second learning. In this case, in the routine shown in FIG. 2, the node sequence α is replaced with the learning node sequence γ, and the node sequence generated after the third time is applied as the node sequence β. As described above, in this embodiment, a node string having a small number of nodes is set as the basic node string κ, and node points not used for learning are integrated as interpolation values of learning data. Therefore, if the number of learning is increased, learning is performed. The number of nodes in the node sequence γ inevitably increases, and the target travel path generated based on the learning node sequence γ becomes finer, and the travel locus desired by the driver can be faithfully reproduced.

  In the present embodiment, the configuration for acquiring the travel route based on the own vehicle position measured by the control device 8 has been described. However, the present invention is not limited to this, and the vehicle position based on the information from the satellite by the mobile station is determined as the reference station 4. The vehicle position can be calculated based on the information of the reference station and the vehicle position in the reference station 4. That is, vehicle position calculation means may be provided on the reference station 4 side. In this case, information such as the target traveling route can be accumulated on the reference station side.

  It is possible to receive information from the reference station and the mobile station at a station other than the reference station 4 instead of the reference station 4 and accumulate information such as the vehicle position and travel route.

Overall configuration diagram of the driving support device Flowchart showing learning node sequence generation routine Explanatory diagram showing the communicable area centered on the reference station Explanatory drawing displaying node sequence on XY coordinate axes (A) is explanatory drawing of the state which converted the node row | line | column into X-distance coordinate, (b) is explanatory drawing which compares the node point of the node row | line | column (beta) by a distance series on the basis of the node row | line | column (alpha). Explanatory drawing showing generation of learning node sequence

Explanation of symbols

1 own vehicle,
2 travel control device,
3 GPS satellites,
4 reference stations,
5a antenna,
8 control device,
9 Vehicle speed sensor,
10 Handle angle sensor,
15 electric throttle valve control device,
16 brake control device,
α, β node sequence,
αn, βn number of nodes,
γ learning node sequence,
κ basic node sequence,
Kn set number,
θH Handle angle,
V vehicle speed

Claims (3)

A reference station for obtaining correction information by correcting the information from the GPS satellite with the installation position as a reference while the installation position is specified;
A mobile station for calculating the vehicle position based on information from the GPS satellites with mounted on the vehicle,
Vehicle position calculation means for correcting and calculating the vehicle position from the correction information of the reference station and the vehicle position when communication between the reference station and the mobile station is established;
Have
The mobile station
Storage means for storing a traveling locus for guiding the vehicle to a destination within a communicable area of the reference station in a node sequence;
A node point to the destination is set based on position information transmitted from the GPS satellite at regular intervals and information transmitted from the reference station, and the node sequence is generated from a set of the node points. Control means,
The control means sets a node sequence having a smaller total number of node points as a basic node sequence based on the two node sequences in the same route, and sets the node point of the basic node sequence and the other node sequence. Compare the node points and select the node point with the smallest distance difference. Based on the selected node points, calculate the average value of the selected node points for each node point in the basic node sequence. A vehicle travel support apparatus that learns a node sequence of a set including the average value as a travel locus for guiding the vehicle to a destination . The control means, the node points which have not been subjected to the learning on other hand node sequence of drive assist apparatus for a vehicle according to claim 1, characterized in that the integration as an interpolation value of the learned the node point. The control means, when the difference between the total number of node points of the node row of the basic node series and the other side is equal to or greater than the set value, claims characterized in that it does not implement the learning of the node points based on these node series Item 3. The vehicle travel support device according to Item 1 or 2 .

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