JP5597472B2 - Road inclination angle detection device and current position calculation device - Google Patents

Description

  The present invention relates to a road inclination angle detection device and a current position calculation device that calculates a current position.

  A car navigation device is known as a current position calculation device that is mounted on a vehicle and calculates the current position of the vehicle. In this car navigation apparatus, the current position of the vehicle is calculated by calculating the inclination angle of the road from the detected inclination angle of the vehicle in the front-rear direction. In this car navigation device, since the inclination angle of the vehicle front-rear direction is calculated from the inclination angle of the car navigation device itself, if the mounting angle of the car navigation device with respect to the vehicle changes, the inclination angle of the road is correctly calculated. Can not. Therefore, in this car navigation device, assuming that the mounting angle of the navigation device to the vehicle is changed, the previously calculated mounting angle is compared with the mounting angle calculated this time, and the difference is a predetermined amount. If it is above, the learning function which calculates | requires the parameter which correct | amends the output of the acceleration sensor which detects the inclination angle of the front-back direction of a vehicle is reset (refer patent document 1).

JP 2009-14732 A

  However, in the above-described conventional car navigation apparatus, even when the vehicle leans in the front-rear direction that is less than the predetermined amount due to the passenger getting on and off, the learning function for obtaining the parameter for correcting the output of the acceleration sensor is not reset. Therefore, there is a possibility that the calculation accuracy of the current position of the vehicle is lowered.

(1) A road inclination angle detection device according to the invention of claim 1 includes an inclination angle detection sensor for detecting an inclination angle in the front-rear direction of the vehicle, and a horizontal road detection for detecting whether or not the vehicle is on a horizontal road. Means, a reference pitch angle acquisition means for acquiring the inclination angle detected by the inclination angle detection sensor as a reference pitch angle when the horizontal road detection means detects that the vehicle is on a horizontal road, and the weight of the vehicle Reference pitch angle reacquisition instructing means for instructing the reference pitch angle obtaining means to reacquire the reference pitch angle when a signal that assumes that there is a variation in distribution is input, and the front and rear of the vehicle detected by the inclination angle detection sensor The inclination angle of the road on which the vehicle is traveling is estimated based on the inclination angle of the direction and the reference pitch angle acquired by the reference pitch angle acquisition means.
(2) The present position calculation device according to the invention of claim 7 is a vehicle in which the road inclination angle detection device according to any one of claims 1 to 6 and the vehicle estimated by the road inclination angle detection device travel. Travel road determination means for determining the road on which the vehicle is traveling based on the inclination angle of the road being present, and current position calculation means for calculating the current position of the vehicle based on the determination result of the travel road determination means It is characterized by.

  According to the present invention, the detection accuracy of the road inclination angle and the calculation accuracy of the current position are improved.

It is a figure which shows the whole structure of a car navigation apparatus. It is a figure which shows the relationship between a vehicle and the inclined road. It is the flowchart which showed the operation | movement of the process which calculates the present position of a vehicle and displays it on a display monitor. It is the flowchart which showed the operation | movement of the process which outputs the instruction | indication of a learning start among the flowcharts concerning learning of the information of the inclination angle (alpha) of a vehicle. It is the flowchart which showed the operation | movement of the process of the learning of the information of the inclination angle (alpha) of a vehicle, and the update process among the flowcharts concerning learning of the inclination angle (alpha) of a vehicle.

  1 to 5, an embodiment in which the road inclination angle detection device and the current position calculation device according to the present invention are applied to a car navigation device will be described. FIG. 1 is a diagram showing an overall configuration of the car navigation apparatus according to the present embodiment. The car navigation device 1 relates to vehicle travel, such as a function for displaying a road map around a vehicle position, a function for calculating a recommended route from a departure place to a destination, and a function for performing route guidance based on the calculated recommended route. It also has a function to present information. The car navigation device 1 is a device that performs so-called navigation or road guidance.

  In FIG. 1, reference numeral 11 denotes a current position detection device that detects the current position of the vehicle. For example, a gyro sensor 11 a for detecting a change in the traveling direction of the vehicle, an acceleration sensor 11 b for detecting acceleration in the front-rear direction of the vehicle, A GPS sensor 11c that detects a GPS signal from a GPS (Global Positioning System) satellite, a vehicle speed sensor 11d that detects a vehicle speed, and the like. The vehicle speed sensor 11d is a sensor provided in the vehicle.

  Reference numeral 100 denotes a control device, which includes a CPU 101 and its peripheral circuits. The CPU 101 and its peripheral circuits are connected to each other via a bus. The peripheral circuit includes a memory 102, a parallel I / O 103, A / D converters 104a and 104b, a serial I / O 105, a counter 106, a graphic controller 107, an image memory 108, a map storage device 109, a parallel I / O 112, and the like. The door opening / closing switch 12 is a switch provided in the vehicle to detect opening / closing of a vehicle door that opens and closes when a passenger gets on and off, and a door that opens and closes a luggage compartment such as a rear trunk, for example. It is provided to turn on and off the room lamp. In the present embodiment, among the door opening / closing switches 12 provided on the vehicle, all the door opening / closing switches except the door opening / closing switch for the door that opens and closes when the passenger gets on and off the driver's seat (door next to the driver's seat). A switch 12 is connected to the parallel I / O 112.

  Reference numeral 14 denotes a display monitor which is disposed at a position where a passenger in the vehicle can visually recognize and displays a map and various types of information. Reference numeral 15 denotes a switch for an occupant to input various operations such as input of a destination of the vehicle. The switch 15 includes a touch panel switch provided on the screen of the display monitor 14 and a joystick for instructing movement of the cursor or scrolling of the screen. The switch 15 may be a remote control switch or a switch provided around the display screen.

  The memory 102 of the control device 100 is a memory including a ROM for storing a control program, a RAM for a work area, and a nonvolatile memory for storing various setting values. The CPU 101 accesses the memory 102, executes a control program, and performs various controls. The parallel I / O 103 is a parallel I / O port to which individual switches constituting the switch 15 are connected. The A / D converters 104a and 104b are converters that A / D convert analog signals from the gyro sensor 11a and the acceleration sensor 11b, respectively. The serial I / O 105 is a serial I / O port that receives a serial signal from the GPS sensor 11c. The counter 106 is a counter that receives and counts, for example, a pulse signal output from the vehicle speed sensor 11d as the axle rotates, that is, a signal related to the travel distance of the vehicle.

  The graphic controller 107 stores display data output from the CPU 101 as image data in a memory 108 that is an image memory (video RAM), and performs control for displaying the image data stored in the memory 108 on the display monitor 14. Do. The display data output from the CPU 101 includes various character data and various graphic data such as a road map. The control device 100 functions as a display control device for the display monitor 14.

  The map storage device 109 is a map storage device that stores various types of information such as road map data and POI information (point of interest sightseeing spots and various facilities information) used for navigation processing, and uses a hard disk device. In addition to the hard disk device, the map storage device 109 may be a CD-ROM or DVD storing road map data, other recording media, and a reading device thereof.

  As described above, the parallel I / O 112 is a parallel I / O port to which all door opening / closing switches 12 except the door opening / closing switch for the door next to the driver's seat are connected.

--- Data structure ---
The road map data is information related to the map, and includes map display data, route search data, guidance data (intersection name / road name / direction name / direction guide / facility information, etc.) and the like. The map display data is data for displaying the road and the background of the road map. The route search data is data including branch information that is not directly related to the road shape, and is mainly used when calculating (route search) a recommended route. The guidance data is data including names of intersections and the like, and is used when the recommended route is guided to the driver or the like based on the calculated recommended route.

  The car navigation device 1 configured as described above performs various types of navigation based on information acquired by the current location detection device 11 and road map data stored in the map storage device 109. For example, the CPU 101 of the control device 100 calculates the current position of the vehicle based on the information acquired by the current position detection device 11 and displays the road map near the current position and the current position of the vehicle on the display monitor 14. Further, the CPU 101 controls each unit so as to guide the driver along the route (recommended route) obtained by the route search.

  In the car navigation device 1 of the present embodiment, the CPU 101 of the control device 100 calculates the current position of the vehicle by so-called satellite navigation based on the positioning information output from the GPS sensor 11c. At that time, a process using known map matching is also performed. If the GPS sensor 11c cannot receive a GPS signal, the CPU 101 cannot calculate the current position of the vehicle by satellite navigation, estimates the current position of the vehicle by so-called autonomous navigation, and performs processing by known map matching. Estimate the current position of the vehicle.

  When the CPU 101 calculates the current position of the vehicle by autonomous navigation, the CPU 101 calculates the turning angle in the left-right direction of the vehicle based on the output from the gyro sensor 11a, and the front-rear direction of the vehicle based on the output from the acceleration sensor 11b. And the travel distance of the vehicle is calculated based on the output from the vehicle speed sensor 11d. Then, the CPU 101 calculates the current position of the vehicle based on the calculated turning angle of the vehicle, the inclination angle in the front-rear direction, and the travel distance.

  When calculating the current position of the vehicle, for example, the CPU 101 determines whether the vehicle is traveling on an elevated road or an elevated road close to the elevated road. Judgment using the data. When calculating the current position of the vehicle by satellite navigation, the CPU 101 calculates the height position of the vehicle based on information related to altitude included in the positioning information output from the GPS sensor 11c. When calculating the current position of the vehicle by autonomous navigation, the CPU 101 calculates the height position of the vehicle by calculating the amount of movement of the vehicle in the vertical direction as follows.

  When the vehicle travels on a sloped road, the vehicle moves in the horizontal direction and the vertical direction. For example, as shown in FIG. 2 (a), when the vehicle travels on a road inclined at an inclination angle θ by a distance L, the vehicle moves by Lcosθ in the horizontal direction and moves by Lsinθ in the vertical direction (height direction). To do. Therefore, if the road inclination angle θ and the travel distance L of the vehicle are known, the amount of movement in the height direction of the vehicle can be calculated. As shown in FIG. 2B, the inclination angle θ is obtained from the output g · sin θ of the acceleration sensor 11b, and the travel distance L is obtained from the output of the vehicle speed sensor 11d.

  A new vehicle height position (altitude) can be calculated by adding the calculated movement amount in the height direction of the vehicle to the original vehicle height position. The calculated new vehicle height position information is stored in the memory 102 for use in the next vehicle height position calculation. That is, a new vehicle height position is calculated by adding the amount of movement of the vehicle in the height direction calculated as described above to the previously calculated vehicle height position stored in the memory 102. it can. It is to be noted that road altitude information is read from road map data stored in the map storage device 109 for roads determined to be running by a known map matching method, and based on the read altitude information. Thus, the vehicle height position calculated as described above may be corrected as appropriate.

  When the vehicle is parallel to the road, the vehicle inclination angle θs calculated based on the acceleration detected by the acceleration sensor 11b coincides with the road inclination angle θ. If the vehicle is stopped or traveling at a constant speed, as shown in FIG. 2 (b), the longitudinal acceleration of the vehicle detected by the acceleration sensor 11b is gsinθ, where g is a gravitational acceleration. When the vehicle is accelerating or decelerating, acceleration in the longitudinal direction of the vehicle due to acceleration or deceleration of the vehicle is also detected by the acceleration sensor 11b. However, since the longitudinal acceleration of the vehicle due to the acceleration or deceleration of the vehicle is equal to the time differential value of the vehicle speed detected by the vehicle speed sensor 11d, the longitudinal acceleration of the vehicle detected by the acceleration sensor 11b and the vehicle speed sensor Only the acceleration detected by the inclination of the vehicle can be calculated from the time differential value of the vehicle speed detected at 11d. Thus, when the vehicle is parallel to the road, the inclination angle θs with respect to the horizontal plane of the vehicle based on the acceleration detected by the acceleration sensor 11b regardless of whether the vehicle is accelerated or decelerated, that is, the road The inclination angle θ can be calculated.

  However, the vehicle is not always parallel to the road due to factors such as passengers and luggage layout. When the vehicle is not parallel to the road, the inclination angle θs of the vehicle with respect to the horizontal plane calculated based on the acceleration detected by the acceleration sensor 11b is, as shown in FIG. This is the sum of the inclination angle α of the vehicle with respect to the road.

  If the vehicle inclination angle α with respect to the road is not taken into account, the road inclination angle θ cannot be calculated correctly, and the amount of movement of the vehicle in the height direction cannot be calculated correctly. Therefore, when the vehicle inclination angle α with respect to the road is not taken into account, the vehicle height position is erroneously calculated, so that the vehicle travels on a different road from the road on which the vehicle actually travels. There is a risk that it will be judged. For example, if a general road and a highway extend at different heights, but the general road and the highway are adjacent to each other on the plane and extend in the same direction, the vehicle inclination angle with respect to the road If α is not taken into consideration, there is a risk of erroneously determining whether the vehicle is traveling on an uphill ramp or a general road without a gradient. For this reason, the current position of the vehicle may not be calculated correctly.

  Similarly, when the inclination angle α of the vehicle with respect to the road is not taken into account, the inclination angle θ of the road is not calculated correctly, and the amount of movement of the vehicle in the horizontal direction cannot be calculated correctly. Therefore, when the vehicle inclination angle α with respect to the road is not taken into account, for example, when traveling on a slope such as a three-dimensional parking lot by autonomous navigation, the horizontal position of the vehicle is erroneously calculated. A position different from the actual current position is calculated as the current position of the vehicle. Further, the difference between the calculated current position of the vehicle and the actual current position of the vehicle becomes larger as the travel distance of the vehicle becomes longer.

  Therefore, the car navigation apparatus 1 according to the present embodiment has a learning function of the vehicle inclination angle α with respect to the road (hereinafter simply referred to as vehicle inclination angle α or reference pitch angle α). Specifically, the CPU 101 of the control device 100 accumulates and averages the acceleration values detected by the acceleration sensor 11b when it is determined that the vehicle is traveling on a horizontal road, and the vehicle inclination angle α. Get the information. The CPU 101 determines the road inclination angle (or change in road elevation) obtained based on the information acquired by the current location detection device 11 and the road map data stored in the map storage device 109, and the current position of the vehicle. Referring to FIG. 4, it is determined whether or not the vehicle is traveling on a horizontal road. The CPU 101 stores the obtained information on the vehicle inclination angle α in the memory 102. Then, the CPU 101 calculates (estimates) the road inclination angle θ based on the acceleration value detected by the acceleration sensor 11 b and the information on the vehicle inclination angle α stored in the memory 102.

  As described above, the car navigation device 1 according to the present embodiment has a learning function of the vehicle inclination angle α. However, when the occupant or the arrangement of luggage changes, the vehicle inclination angle α also changes. End up. Therefore, there is a possibility that the information on the vehicle inclination angle α once learned will become obsolete due to changes in the number of passengers and the arrangement of luggage.

  Therefore, in the car navigation apparatus 1 according to the present embodiment, when the doors other than the door next to the driver's seat and the door for opening and closing the luggage compartment such as the rear trunk are opened and closed, the arrangement of passengers and luggage changes. Assuming that the vehicle weight distribution may have changed and that the vehicle inclination angle α may have changed, information on the vehicle inclination angle α is again learned and acquired. That is, when the CPU 101 of the control device 100 detects a change in the output signal of the door opening / closing switch 12, the CPU 101 considers that there is a change in the weight distribution of the vehicle, and re-learns and acquires information on the vehicle inclination angle α. To control.

  Specifically, when the CPU 101 detects a change in the output signal of the door opening / closing switch 12, the CPU 101 accumulates acceleration values detected by the acceleration sensor 11b when it is determined that the vehicle is traveling on a horizontal road. To obtain information on the inclination angle α of the new vehicle. Then, the CPU 101 updates the information on the vehicle inclination angle α already stored in the memory 102 with the newly obtained information on the vehicle inclination angle α.

  Note that the CPU 101 constantly monitors changes in the output signal of the door opening / closing switch 12 regardless of whether the vehicle is traveling or whether an ignition switch (not shown) is on or off.

--- Flow chart for current position calculation processing ---
FIG. 3 is a flowchart showing the operation of processing for calculating the current position of the vehicle and displaying it on the display monitor 14. For example, when the car navigation device 1 is turned on, for example, when an accessory switch is turned on (ACC ON) by an ignition key (not shown) of the vehicle, a program for performing the processing shown in FIG. Executed. In step S1, various data output from the current position detection device 11 and the like are read, and the process proceeds to step S3. In step S3, it is determined whether or not the positioning information output from the GPS sensor 11c has been acquired when various data are read in step S1.

  If an affirmative determination is made in step S3, the process proceeds to step S5, and a vehicle current position calculation process is performed by satellite navigation. Since the vehicle current position calculation process by satellite navigation is known, detailed description thereof is omitted. In step S5, a known map matching process is also performed. If step S5 is performed, it will progress to step S7 and will memorize | store the calculated present position of the vehicle. Note that the information on the current position of the vehicle stored in step S7 is used in the next calculation of the current position of the vehicle.

  When step S7 is executed, the process proceeds to step S9, and based on the calculated current position of the vehicle, each part is controlled to superimpose and display a car mark indicating the current position of the vehicle on the map displayed on the display monitor 14. And return.

  If a negative determination is made in step S3, the process proceeds to step S11. Based on the voltage value of the acceleration sensor 11b read in step S1 and information on the vehicle inclination angle α stored in the memory 102, the road inclination angle θ. Is calculated and the process proceeds to step S13. In step S13, the travel distance L of the vehicle is calculated based on the vehicle speed data read in step S1, and the vertical movement amount Lsinθ of the vehicle and the horizontal direction based on the road inclination angle θ calculated in step S11. Is calculated, and the process proceeds to step S15.

  In step S15, the vehicle movement amounts Lsinθ and Lcosθ calculated in step S13 are added to the height position and horizontal position of the vehicle calculated in the previous process and stored in the memory 102, respectively. The position is calculated and the process proceeds to step S17. In step S17, the vehicle current position calculation process by autonomous navigation is performed using the vehicle position calculated in step S15 as the current vehicle position. Note that the vehicle current position calculation processing by autonomous navigation is well known, and thus detailed description thereof is omitted. In step S17, a known map matching process is also performed. When step S17 is executed, the process proceeds to step S7.

--- Flow chart for learning information of vehicle inclination angle α ---
FIG. 4 is a flowchart showing an operation of a process for outputting an instruction to start learning, among the flowcharts related to learning of information on the vehicle inclination angle α. The program for performing the process shown in FIG. 4 is always executed by the CPU 101 as long as backup power is supplied from the vehicle to the car navigation apparatus 1. In step S21, for example, it is determined whether or not it is an initial state in which learning of the information of the vehicle inclination angle α is not performed as in the factory shipment state.

  If a negative determination is made in step S21, the process proceeds to step S23 and waits until a change in the output signal of the door open / close switch 12 is detected. If an affirmative determination is made in step S23, the process proceeds to step S25, where 1 is set in a flag (learning start instruction flag) for instructing the start of learning of information on the vehicle tilt angle α, and the process returns to step S23. If step S21 is affirmed, the process proceeds to step S25.

  FIG. 5 is a flowchart showing an operation of acquiring information on the vehicle tilt angle α, that is, learning and updating information on the vehicle tilt angle α, among the flowcharts related to learning of the vehicle tilt angle α. It is. For example, when the car navigation device 1 is turned on, for example, when an accessory switch is turned on (ACC ON) by an ignition key (not shown) of the vehicle, a program for performing the process shown in FIG. Executed. In step S31, the process waits until 1 is set in the learning start instruction flag.

  When an affirmative determination is made in step S31, the process proceeds to step S33, and learning of information on the vehicle inclination angle α is started. Specifically, as described above, the acceleration value detected by the acceleration sensor 11b when it is determined that the vehicle is traveling on a horizontal road is accumulated and averaged, and information on the vehicle inclination angle α is obtained. Start the operation to get If step S33 is performed, it will progress to step S35 and will wait until the learning of the information of the inclination-angle (alpha) of a vehicle is complete | finished. When an affirmative determination is made in step S35, the process proceeds to step S37, where the information on the vehicle inclination angle α already stored in the memory 102 is updated with the newly obtained information on the vehicle inclination angle α. Note that when the vehicle 102 is in an initial state in which the information on the vehicle inclination angle α is not stored (the factory default value is stored), the obtained information on the vehicle inclination angle α is stored in the memory 102. 102.

  When step S37 is executed, the process proceeds to step S39, the learning start instruction flag is set to 0, and the process returns to step S31.

The car navigation device 1 described above has the following operational effects.
(1) When there is a possibility that the weight distribution of the vehicle may fluctuate due to changes in personnel or luggage arrangement, the information on the vehicle inclination angle α is learned and acquired again. As a result, the inclination angle θ of the road on which the vehicle travels is correctly calculated, and the height position and the horizontal position of the vehicle are correctly calculated. Accordingly, the current position of the vehicle is correctly calculated, and the current position calculation accuracy of the car navigation device 1 can be improved. For example, a general road and a highway extend at different heights, but a general road and a highway are adjacent to each other on the plane and extend in the same direction. It is possible to improve the accuracy of determining whether the vehicle is traveling on an uphill ramp or a general road with no gradient.

(2) When a change in the output signal of the door opening / closing switch 12 is detected, it is assumed that there is a change in the weight distribution of the vehicle, and information on the vehicle inclination angle α is learned again and acquired. That is, the change in the output signal of the door opening / closing switch 12 was used as a trigger for relearning the information on the vehicle inclination angle α. Thereby, it is not necessary to add new sensors, and an increase in cost can be suppressed.

(3) If the driver is not present, the vehicle cannot travel. When the vehicle travels, the driver is always seated in the driver's seat. There is no need to relearn information on the inclination angle α. Therefore, in the present embodiment, changes in the output signal of the door opening / closing switch 12 for doors other than the door next to the driver's seat and doors for opening and closing the luggage compartment such as the rear trunk are relearned as information on the vehicle inclination angle α. The trigger was Thereby, unnecessary relearning can be suppressed and the calculation load of the CPU 101 can be suppressed.

(4) A change in the output signal of the door opening / closing switch 12 is constantly monitored regardless of whether the vehicle is traveling or whether an ignition switch (not shown) is on or off. Accordingly, it is possible to suppress a problem that information on the vehicle inclination angle α is not relearned even though the vehicle inclination angle α is changed due to a change in the number of passengers and luggage.

---- Modified example ---
(1) In the above description, when it is determined that the vehicle is traveling on a horizontal road, the acceleration values detected by the acceleration sensor 11b are accumulated and averaged to obtain information on the vehicle inclination angle α. Although configured as described above, the present invention is not limited to this. For example, even when it is determined that the vehicle is traveling on a non-horizontal road, information on the inclination angle of the road obtained by referring to the road map data and the acceleration value detected by the acceleration sensor 11b Based on the above, the vehicle inclination angle α may be obtained.

(2) As described above, only the acceleration detected by the inclination of the vehicle can be calculated from the longitudinal acceleration of the vehicle detected by the acceleration sensor 11b and the time differential value of the vehicle speed detected by the vehicle speed sensor 11d. . Therefore, even if the acceleration value is detected by the acceleration sensor 11b when the vehicle is accelerating / decelerating, it can be used to obtain information on the vehicle inclination angle α.

(3) From the positional relationship between the seat and the wheel, the opening / closing of the door next to the seat need not be monitored for a seat that has little influence on the vehicle inclination angle α due to the presence or absence of a passenger. For example, in the case of a vehicle having a passenger seat near the center of the front and rear wheels, such as a general sedan type passenger car, it is not necessary to monitor the opening and closing of the door next to the passenger seat.

(4) In the above description, when the current position of the vehicle is calculated by satellite navigation, the CPU 101 calculates the height position of the vehicle based on information related to altitude included in the positioning information output from the GPS sensor 11c. However, the present invention is not limited to this. For example, during the vehicle current position calculation process by satellite navigation, the CPU 101 stores the acceleration value detected by the acceleration sensor 11b and the memory 102, as in the case of calculating the vehicle current position by autonomous navigation. Based on the information on the inclination angle α of the existing vehicle, the road inclination angle θ may be calculated to calculate the height position of the vehicle.

(5) In the above description, when calculating the current position of the vehicle, for example, whether the vehicle is traveling on an elevated road or an elevated road adjacent to the elevated road, Although the CPU 101 is configured to make a determination using the vehicle height position data, the present invention is not limited to this. For example, when the current position of the vehicle is calculated, the road inclination angle θ estimated based on the acceleration value detected by the acceleration sensor 11 b and the information on the vehicle inclination angle α stored in the memory 102. By comparing the inclination angle of the road obtained based on the road map data stored in the map storage device 109, for example, whether the vehicle is traveling on an elevated road or close to the elevated road You may comprise so that it may be judged whether it is drive | working the road under an overpass.

(6) In the above description, when a change in the output signal of the door opening / closing switch 12 is detected, it is considered that there is a change in the weight distribution of the vehicle, and the information on the vehicle inclination angle α is learned and acquired again. However, the present invention is not limited to this. For example, instead of a change in the output signal of the door opening / closing switch 12, a change in the output signal of a sensor that detects the attachment / detachment of the seat belt may be detected.

(7) In the above description, after the relearning is completed, the information on the vehicle inclination angle α that has already been stored in the memory 102 is updated with the newly obtained information on the vehicle inclination angle α. However, the present invention is not limited to this. For example, when a change in the output signal of the door opening / closing switch 12 is detected, the information on the vehicle inclination angle α stored in the memory 102 is temporarily deleted, temporary information is stored in the memory 102, and the relearning is completed. Later, provisional information stored in the memory 102 may be updated with information on the newly obtained vehicle inclination angle α.

(8) For example, in order to determine whether the passenger is getting on and off the rear seat or whether the driver has just opened and closed the door next to the rear seat, The above-described relearning may be started when it is estimated that the passenger is getting on and off the rear seat by comparing the opening / closing timing of the door. As an example, for example, if it is detected that the door next to the driver's seat and the door next to the rear seat are closed at the same time, and then the vehicle starts running without opening and closing the door next to the driver's seat, It may be considered that passengers get on and off the rear seats.
(9) You may combine each embodiment and modification which were mentioned above, respectively.

  Note that the present invention is not limited to the embodiment described above, and an inclination angle detection sensor that detects an inclination angle in the front-rear direction of the vehicle, and when the vehicle is detected to be on a horizontal road. The reference pitch angle acquisition means for acquiring the inclination angle detected by the inclination angle detection sensor as the reference pitch angle, and the reference so that the reference pitch angle is re-acquired when a signal that the vehicle weight distribution is considered to be varied is input. Based on the reference pitch angle reacquisition instruction means for instructing the pitch angle acquisition means, the vehicle front-rear direction inclination angle detected by the inclination angle detection sensor, and the reference pitch angle acquired by the reference pitch angle acquisition means Inclination angle detection device for roads of various structures characterized by estimating the inclination angle of the road on which the vehicle is traveling, and current structures of various structures equipped with this road inclination angle detection device It is intended to include 置算 detection device.

DESCRIPTION OF SYMBOLS 1 Car navigation apparatus 11 Present location detection apparatus 11a Gyro sensor 11b Acceleration sensor 11d Vehicle speed sensor 12 Door open / close switch 14 Display monitor 100 Control apparatus 101 CPU 109 Map storage apparatus

Claims (7)

An inclination angle detection sensor for detecting an inclination angle in the front-rear direction of the vehicle;
Horizontal road detection means for detecting whether the vehicle is on a horizontal road;
Reference pitch angle acquisition means for acquiring, as a reference pitch angle, an inclination angle detected by the inclination angle detection sensor when the horizontal road detection means detects that the vehicle is on a horizontal road;
A reference pitch angle reacquisition instructing means for instructing the reference pitch angle obtaining means to reacquire the reference pitch angle when a signal that is regarded as a change in weight distribution of the vehicle is input;
Estimating the inclination angle of the road on which the vehicle is traveling based on the inclination angle in the front-rear direction of the vehicle detected by the inclination angle detection sensor and the reference pitch angle acquired by the reference pitch angle acquisition means. A road inclination angle detecting device characterized by the above. The road inclination angle detecting device according to claim 1,
The road inclination angle detecting device, wherein the signal is an output signal that is output when at least one of a door that opens and closes when a passenger gets on and off and a door that opens and closes a cargo compartment. The road inclination angle detecting device according to claim 2,
The road inclination angle detection is characterized in that the signal is an output signal that is output when at least one of a door that opens and closes when a passenger other than the driver gets on and off and a door that opens and closes the cargo compartment. apparatus. The road inclination angle detecting device according to claim 1,
The road inclination angle detecting device according to claim 1, wherein the signal is an output signal that is output when a seat belt is worn. The road inclination angle detecting device according to claim 4,
The road inclination angle detection device is an output signal that is output when the seat belt other than the driver's seat is changed. In the road inclination angle detection device according to any one of claims 1 to 5,
The reference pitch angle reacquisition instructing means detects whether or not the signal is input regardless of whether or not the vehicle is running. The road inclination angle detection device according to any one of claims 1 to 6,
Traveling road determination means for determining the road on which the vehicle is traveling based on the inclination angle of the road on which the vehicle is traveling, estimated by the road inclination angle detection device;
A current position calculation device comprising: a current position calculation unit that calculates a current position of the vehicle based on a determination result of the traveling road determination unit.

Images