Navigation Device

Abstract

To provide a navigation device which can suppress the occurrence of shortage of a hydrogen residual amount after the arrival at a destination location.SOLUTION: A navigation device which is mounted on a fuel cell vehicle having a fuel cell using hydrogen gas as fuel gas and executes route guide of the fuel cell vehicle comprises: an acquisition unit which acquires a current hydrogen amount A and a hydrogen consumption amount X predicted to be consumed by the time arriving at a destination location; a specification unit which specifies a first hydrogen station existing in the periphery of a route from the current location to the destination location and a second hydrogen station closest to the destination location; a calculation unit which calculates a predicted hydrogen residual amount B(B=A-X) at the time of arrival at the destination location and a necessary hydrogen amount C necessary at the time of arrival at the destination location; and a route setting unit. The route setting unit changes the route from the current location to the destination location to a route passing through the first hydrogen station when the predicted hydrogen residual amount B is smaller than the necessary hydrogen amount C(B<C).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a navigation device. [Background technology]

[0002] A fuel cell (FC) is a power generation device that is composed of one unit cell (hereinafter sometimes referred to as a cell) or a fuel cell stack (hereinafter sometimes simply referred to as a stack) made up of multiple stacked unit cells, and produces electrical energy through an electrochemical reaction between a fuel gas such as hydrogen and an oxidant gas such as oxygen. In the following, the fuel gas and the oxidant gas may be simply referred to as "reactant gas" or "gas" without any particular distinction. In addition, both a single cell and a fuel cell stack formed by stacking single cells may be referred to as a fuel cell.

[0003] Various research projects have been conducted on devices that are mounted on fuel cell vehicles (FCEVs, hereinafter sometimes referred to as vehicles). For example, Patent Document 1 discloses a fuel cell vehicle that is configured to identify hydrogen stations (ST) that are within a driving distance range, compare the driving distance with the distance to the destination, and change the route to pass through the hydrogen ST if the distance to the destination is longer than the driving distance.

[0004] Patent Document 2 discloses a route search device that estimates the remaining battery power upon arrival at a destination and determines, as a recommended route, the route that comes closest to a designated amount of power. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2021-110547 A [Patent Document 2] International Publication No. 2013 / 172157 Summary of the Invention

Problems to be Solved by the Invention

[0006] In a fuel cell vehicle, although it can reach the destination, there is a risk that the hydrogen fuel will be exhausted upon arrival at the destination, and the remaining hydrogen amount will be insufficient after arrival at the destination. In a fuel cell vehicle, there are needs such as wanting to leave the amount of hydrogen to the nearest hydrogen station from the destination, and wanting to use the fuel cell vehicle as a generator at a campsite or the like. It is possible.

[0007] In view of the above circumstances, the present disclosure is made, and a main object thereof is to provide a navigation device capable of suppressing the occurrence of insufficient remaining hydrogen amount after arrival at the destination.

Means for Solving the Problems

[0008] The navigation device of the present disclosure is mounted on a fuel cell vehicle having a fuel cell that uses hydrogen gas as a fuel gas, and is a navigation device that executes route guidance for the fuel cell vehicle, an acquisition unit that acquires the current hydrogen amount A and the hydrogen consumption amount X expected to be consumed until the destination; a specifying unit that specifies a first hydrogen station existing around the route from the current location to the destination and a second hydrogen station nearest to the destination; a calculation unit that calculates an expected remaining hydrogen amount B (B = A - X) at the time of arrival at the destination and a required hydrogen amount C required at the time of arrival at the destination; and a route setting unit. The route setting unit is characterized in that, when the expected remaining hydrogen amount B is smaller than the required hydrogen amount C (B < C), the route from the current location to the destination is changed to a route passing through the first hydrogen station.

[0009] In the navigation device of the present disclosure, the required hydrogen amount C may be the minimum required hydrogen amount F that can reach the second hydrogen station from the destination.

[0010] In the navigation device of the present disclosure, the acquisition unit acquires a planned hydrogen usage amount D to be used at the destination, The route setting unit may perform route search so as to leave a minimum required amount of hydrogen F for reaching the second hydrogen station from the destination and the planned amount of hydrogen usage D.

[0011] In the navigation device of the present disclosure, the planned hydrogen usage amount D may be a value that is statistically calculated from a user input value or a destination attribute.

[0012] In the navigation device of the present disclosure, the route setting unit may, when a predetermined location is set during destination setting, issue a command to confirm whether or not hydrogen is required to be used at the destination.

[0013] In the navigation device of the present disclosure, the route setting unit may issue an alarm if there is a risk that the amount of hydrogen F required to reach the second hydrogen station from the destination will fall below the minimum amount of hydrogen F required during use of hydrogen at the destination.

[0014] In the navigation device of the present disclosure, when the planned hydrogen usage amount D is a value statistically calculated from the destination attributes, the acquisition unit may compare the amount of hydrogen consumption E actually consumed at the destination with the planned hydrogen usage amount D to calculate an error, accumulate data on the error, and correct the planned hydrogen usage amount D in accordance with the error.

[0015] In the navigation device of the present disclosure, the route setting unit may, in changing the route, select from among the two or more first hydrogen stations, a hydrogen station that has the smallest amount of hydrogen consumption Y predicted to be consumed from the current location to the destination via the hydrogen station. Effect of the Invention

[0016] According to the navigation device of the present disclosure, it is possible to prevent the occurrence of a shortage of hydrogen after arriving at a destination. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a flowchart showing an example of a procedure for a navigation device of the present disclosure to provide route guidance from a current location to a destination so as to leave a minimum amount of hydrogen necessary to reach the nearest hydrogen station upon reaching the destination. [Diagram 2] FIG. 2 is a diagram showing an example of a case where a route is provided that satisfies the condition B≧C or B'≧C, in which the condition is met without stopping at a hydrogen ST, a case where the condition is met but a stop is made at the ST, and a case where the condition is not met and a case where the condition is met. [Diagram 3] 3 is a flowchart showing an example of a procedure in which the navigation device of the present disclosure changes the route from the current location to the destination in accordance with the planned amount of hydrogen usage D to be used at the destination. First, the destination is input into the navigation device. [Figure 4] FIG. 4 is a diagram showing an example of a case where a route is provided that satisfies the condition B≧F+D or B′≧F+D, where the condition is met without stopping at a hydrogen ST, a case where the condition is not met but a stop is made at the ST, and a case where the condition is met. [Diagram 5] FIG. 5 is a flowchart showing an example of guidance performed by the navigation device of the present disclosure when a destination has not been set. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] A navigation device according to the present disclosure is a navigation device that is mounted on a fuel cell vehicle having a fuel cell that uses hydrogen gas as a fuel gas, and that performs route guidance for the fuel cell vehicle, An acquisition unit that acquires a current amount of hydrogen A and an amount of hydrogen consumption X that is expected to be consumed until the destination is reached; an identification unit that identifies a first hydrogen station located in the vicinity of a route from a current location to the destination and a second hydrogen station that is closest to the destination; A calculation unit that calculates an expected remaining amount of hydrogen B (B=AX) upon arrival at the destination and a required amount of hydrogen C upon arrival at the destination; It has a route setting unit, When the predicted remaining hydrogen amount B is less than the required hydrogen amount C (B < C), the route setting unit is characterized by changing the route from the current location to the destination to a route passing through the first hydrogen station.

[0019] The navigation device of the present disclosure performs route search, searches for hydrogen ST on the route, and guides the route, leaving at least the minimum required hydrogen amount F that can reach the nearest hydrogen ST (second hydrogen station) from the destination as the required hydrogen amount C required when arriving at the destination. Furthermore, when there is hydrogen availability at the destination, the remaining hydrogen amount is increased by the amount of hydrogen planned to be used D at the destination according to the usage purpose. In the present disclosure, each value of the current hydrogen amount A, the predicted remaining hydrogen amount B, the predicted remaining hydrogen amount B' at the time of arriving at the destination from the candidate hydrogen ST (first hydrogen station), the required hydrogen amount C required at the destination, the planned hydrogen usage amount D to be used at the destination, the hydrogen consumption amount E actually consumed at the destination, the required hydrogen amount F from the destination to the nearest hydrogen ST of the destination, the hydrogen amount G required from the current location to the nearest hydrogen ST, the predicted hydrogen consumption amount X expected to be consumed until the destination, the predicted hydrogen consumption amount Y from the current location to the destination via the candidate hydrogen ST, and the predicted hydrogen consumption amount Z from the candidate hydrogen ST to the destination may be represented by a percentage value (%) of hydrogen or by mass (kg).

[0020] The navigation device of the present disclosure is mounted on a fuel cell vehicle having a fuel cell that uses hydrogen gas as a fuel gas and is used to execute route guidance for the fuel cell vehicle.

[0021] The fuel cell vehicle has a fuel cell as a power source for a traction motor. The fuel cell may have only one power generation element that can generate electricity even as a single unit called a single cell, or may be a fuel cell stack that is a laminate in which a plurality of single cells are stacked. The number of stacked single cells is not particularly limited, and may be, for example, 2 to several hundred. In this embodiment, the fuel cell is a solid polymer fuel cell, and hydrogen gas is used as the fuel gas and air is used as the oxidizing gas. In addition to a fuel cell, a fuel cell vehicle is equipped with a hydrogen gas system that supplies hydrogen gas to the fuel cell, including a hydrogen tank for storing hydrogen gas, a hydrogen gas supply line for supplying hydrogen gas from the hydrogen tank to the fuel cell, a main stop valve, a pressure sensor, etc.

[0022] The navigation device of the present disclosure includes an acquisition unit, an identification unit, a calculation unit, and a route setting unit, and typically includes a display unit and the like.

[0023] The acquisition unit, the identification unit, the calculation unit, and the route setting unit may be controlled by a control unit that controls the entire navigation device. The control unit is composed of a computer equipped with a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a GNSS function unit. The CPU reads out a control program stored in the ROM, expands it in the RAM, and executes it, thereby functioning as an acquisition unit, a specification unit, a calculation unit, and a route setting unit.

[0024] The ROM stores map information in advance in addition to the control program described above. This map information includes information such as the location and size of roads and intersections, as well as the size and type of buildings. Therefore, information about hydrogen stations is also included in the map information. Information about hydrogen stations included in the map information includes, for example, the name of each hydrogen station, i.e., "first hydrogen station" and "second hydrogen station," as well as the location of each hydrogen station, and information about the outline and size of the site and buildings.

[0025] The GNSS function unit determines the current location (latitude and longitude) of the fuel cell vehicle using the Global Navigation Satellite System (GNSS). The GNSS may be any type of GNSS, such as GPS (Global Positioning System), Galileo, or QZSS.

[0026] The acquisition unit acquires the current hydrogen amount A and the hydrogen consumption amount X that is expected to be consumed up to the destination. The acquisition unit may, for example, use the pressure inside the hydrogen tank detected by a pressure sensor to determine the current hydrogen amount A. The current hydrogen amount A may be determined, for example, by storing in advance in a ROM a map that associates the pressure inside the hydrogen tank with the remaining amount of hydrogen (current hydrogen amount A) and by referring to the map. Alternatively, for example, an arithmetic expression that expresses the relationship between pressure and remaining amount of hydrogen may be determined in advance, and the remaining amount of hydrogen may be calculated by applying the pressure value to the arithmetic expression. The acquisition unit may acquire the hydrogen consumption amount X from the average vehicle speed and the amount of hydrogen consumed from when the fuel cell vehicle was started to the present time.

[0027] The identification unit identifies a first hydrogen station that is present in the vicinity of a route from a current location to a destination, and a second hydrogen station that is closest to the destination. The first hydrogen station may be a hydrogen station located on the shortest route from the current location to the destination, or a nearest hydrogen station located in the vicinity of the shortest route.

[0028] The calculation unit calculates the expected remaining amount of hydrogen B (B=AX) upon arrival at the destination, and the required amount of hydrogen C required upon arrival at the destination. The required amount of hydrogen C may be the minimum amount of hydrogen F required to reach the second hydrogen station from the destination. The minimum amount of hydrogen F required may include a margin so that the remaining amount of hydrogen does not become zero when the vehicle reaches the second hydrogen station. When calculating the route via the first hydrogen station, the calculation unit calculates the predicted hydrogen consumption Y from the current location to the destination via the candidate hydrogen ST (the first hydrogen station), calculates the predicted hydrogen consumption Z from the candidate hydrogen ST to the destination, and calculates the predicted remaining hydrogen amount B' at the destination arrival from the candidate hydrogen ST. For example, when assuming that the hydrogen is replenished until it is full at 100 at the candidate hydrogen ST, it may be calculated from Equation 1 (B' = 100 - Z). In Equation 1, 100 is a value when assuming that the hydrogen is replenished until it is full at 100 at the candidate hydrogen ST, and thus it can be appropriately changed according to the amount of hydrogen replenished at the candidate hydrogen ST.

[0029] The route setting unit sets the target route of the fuel cell vehicle. The target route means a route set as the route that the fuel cell vehicle passes through until it reaches the destination. In the present embodiment, the route setting unit causes the display unit to display a menu screen for route setting. When the user sets a destination on such a menu screen, the route from the current location of the fuel cell vehicle to the destination is searched and set according to a predetermined algorithm. The above-mentioned "predetermined algorithm" may be an algorithm for obtaining the shortest distance such as Dijkstra's method in the present embodiment. Note that, as an algorithm for searching the target route by the route setting unit, instead of the algorithm for obtaining the shortest distance, or in addition to such an algorithm, other types of algorithms such as an algorithm for obtaining a route that reaches in the shortest time considering the driving time zone, toll roads, etc., or an algorithm for obtaining the route with the lowest cost may be used. When the predicted remaining hydrogen amount B is smaller than the required hydrogen amount C (B < C), the route setting unit changes the route from the current location to the destination to a route via the first hydrogen station. In the route change, the route setting unit may select the hydrogen station with the minimum predicted hydrogen consumption Y that is expected to be consumed until reaching the destination via the hydrogen station from the current location among two or more first hydrogen stations. When it is not possible to reach the destination even via the first hydrogen station, the route setting unit may search for a route that stops at two or more hydrogen STs, or may notify that it is impossible to reach. The notification may be displayed on the screen which is the display unit.

[0030] The display unit displays, in addition to the map image, various menu screens, messages, alerts, etc. The display unit may be configured by a touch panel and accepts operations by the user.

[0031] (First Embodiment) FIG. 1 is a flowchart showing an example of a procedure for guiding a route from the current location to a destination so that the navigation device of the present disclosure leaves the minimum amount of hydrogen that can reach the nearest hydrogen ST when the destination is reached. First, a destination is input to the navigation device. Thereafter, the acquisition unit acquires the current hydrogen amount A and the hydrogen consumption amount X that is expected to be consumed until the destination. The calculation unit calculates the predicted hydrogen remaining amount B (B = A - X) at the time of arrival at the destination and the required hydrogen amount C required at the time of arrival at the destination. As the required hydrogen amount C required at the time of arrival at the destination, the minimum required hydrogen amount F that can reach the second hydrogen station from the destination may be calculated, or the planned hydrogen usage amount D to be used at the destination described later may be included. When the predicted hydrogen remaining amount B is equal to or greater than the required hydrogen amount C required at the time of arrival at the destination (B ≧ C), the route setting unit sets a route that does not guide to the hydrogen ST. On the other hand, when the predicted hydrogen remaining amount B is less than the required hydrogen amount C required at the time of arrival at the destination (B < C), the specifying unit picks up hydrogen ST candidates that can be reached from the current location and exist around the route from the current location to the destination. For example, by comparing the current hydrogen amount A with the hydrogen amount G required from the current location to the nearest hydrogen ST, it can be determined whether it is reachable from the current location. The calculation unit calculates the predicted hydrogen consumption amount Y from the current location to the destination via the candidate hydrogen ST, calculates the predicted hydrogen consumption amount Z from the candidate hydrogen ST to the destination, and calculates the predicted hydrogen remaining amount B' at the time of arrival at the destination from the candidate hydrogen ST from Equation 1 (B' = 100 - Z). In Equation 1, 100 is used on the premise that the candidate hydrogen ST to stop at is filled with hydrogen to full, but it may be variable. The route setting unit then searches whether there is a hydrogen ST where B'≧C, and if not, notifies the user that it is not possible to reach the destination in a single stop at the hydrogen ST and ends the search, or it may search for a route that includes stops at two or more hydrogen STs. On the other hand, if there is a hydrogen station for which B'≧C, the route setting unit selects the hydrogen station with the smallest Y from among the multiple hydrogen station candidates, and determines it as the first hydrogen station. Then, the route from the current location to the destination is changed to a route that passes through the first hydrogen station, and this route is determined as the guide route.

[0032] FIG. 2 is a diagram showing an example of a case where a route is provided that satisfies the condition B≧C or B'≧C, in which the condition is met without stopping at a hydrogen ST, a case where the condition is met but a stop is made at the ST, and a case where the condition is not met and a case where the condition is met. As a premise, the hydrogen tank is full at 100 when the vehicle is currently at the destination and when it stops at the hydrogen station. The minimum amount of hydrogen required to reach the second hydrogen station from the destination, F, is set to a minimum of 30, which is the amount of hydrogen required to reach the destination, C (C=F). (i) Route 1 in Case 1 is a case in which condition B≧C is met without hydrogen refueling, (ii) Route 1 in Case 2 is a case in which condition B≧C is not met without hydrogen refueling, Route 2 is a case in which hydrogen is refueled but condition B'≧C is not met (a case in which hydrogen is wasted due to a nearby hydrogen ST), Route 3 is the first example of a case in which hydrogen is refueled and condition B'≧C is met, and Route 4 is the second example of a case in which hydrogen is refueled and condition B'≧C is met. When stopping at a hydrogen station (ii), routes 3 and 4 in case 2 both satisfy the conditions, but route 3 may be selected since it has a shorter total distance from the departure point to the destination via the hydrogen station.

[0033] Second embodiment The acquisition unit may acquire a planned hydrogen usage amount D to be used at the destination. The route setting unit may perform route search so as to leave the minimum amount of hydrogen F required to reach the second hydrogen station from the destination and the planned amount of hydrogen D to be used at the destination as the amount of hydrogen C required upon arrival at the destination. In other words, in this case, the amount of hydrogen C required upon arrival at the destination includes the minimum amount of hydrogen F required to reach the second hydrogen station from the destination and the planned amount of hydrogen D to be used at the destination (C=F+D). For example, when the destination is a specific location such as a campsite, the recommended route may be changed according to the planned amount D of hydrogen to be used at the destination. In the example shown in Figure 1, the amount of hydrogen remaining at the time of arrival at the destination is set to "the amount that can be filled up at the nearest hydrogen station at the very least," but depending on the purpose of use at the destination, there may be a need to increase the remaining amount (e.g., the destination is a campsite and you want to charge up on-site). Therefore, the guided route is changed according to the planned amount of hydrogen D to be used at the destination.

[0034] The planned amount of hydrogen used at the destination D may be a user-entered value or a value statistically calculated from the destination attributes. If the planned amount of hydrogen usage D to be used at the destination is a value statistically calculated from destination attributes, the acquisition unit may compare the amount of hydrogen consumption E actually consumed at the destination with the planned amount of hydrogen usage D to be used at the destination to calculate an error, accumulate data on the error, and correct the planned amount of hydrogen usage D in accordance with the error. The data collected by the vehicle may be transmitted to an information center. Data may be transmitted using any type of wireless communication, such as mobile communications provided by telecommunications carriers, such as 4G (4th Generation) communication, LTE (Long Time Evolution) communication, 5G (5th Generation) communication, or wireless LAN (Local Area Network).

[0035] When a predetermined location is set when setting the destination, the route setting unit may issue a command to confirm whether or not hydrogen is required at the destination in order to prompt the user to input the planned amount D of hydrogen to be used at the destination. The command may be displayed on a screen serving as a display unit.

[0036] The route setting unit may sound an alarm if, during the use of hydrogen at the destination, there is a risk that the amount of hydrogen will fall below the minimum amount F required to reach the second hydrogen station from the destination. The alarm may be displayed on a screen that is the display unit, or an alarm may be emitted. The point at which there is a risk that the amount of hydrogen will fall below the minimum amount F required to reach the second hydrogen station from the destination may be when the remaining amount of hydrogen reaches the minimum amount of hydrogen F required to reach the second hydrogen station from the destination, or when the remaining amount of hydrogen reaches a predetermined amount before reaching the minimum amount of hydrogen F required to reach the second hydrogen station from the destination.

[0037] FIG. 3 is a flowchart showing an example of a procedure for changing a route from a current location to a destination in accordance with a planned amount D of hydrogen to be used at the destination by the navigation device of the present disclosure. First, the destination is input into the navigation device. Thereafter, the acquisition unit acquires the current hydrogen amount A and the hydrogen consumption amount X that is expected to be consumed up to the destination. The calculation unit calculates the expected remaining hydrogen amount B (B=AX) upon arrival at the destination, and the minimum required amount of hydrogen F to reach the second hydrogen station from the destination. The acquisition unit acquires the planned amount of hydrogen usage D to be used at the destination (the planned amount of hydrogen usage D may be determined by the system based on the destination attributes, or may be determined by the user's will). If the estimated remaining hydrogen amount B is equal to or greater than the minimum required hydrogen amount F to reach the second hydrogen station from the destination plus the planned hydrogen usage amount D (B≧F+D), the route setting unit sets a route that does not guide the vehicle to the hydrogen ST. On the one hand, when the predicted hydrogen remaining amount B is less than the minimum required hydrogen amount F to reach the second hydrogen station from the destination plus the planned hydrogen usage amount D to be used at the destination (B < F + D), the specifying unit picks up hydrogen ST candidates reachable from the current location that exist around the route from the current location to the destination. The calculating unit calculates the predicted hydrogen consumption amount Y from the current location to the destination via the candidate hydrogen ST, calculates the predicted hydrogen consumption amount Z from the candidate hydrogen ST to the destination, and calculates the predicted hydrogen remaining amount B' at the time of reaching the destination from the candidate hydrogen ST using Equation 1 (B' = 100 - Z). In Equation 1, 100 is assumed on the premise that the candidate hydrogen ST to stop at is filled with hydrogen to full capacity, but it can be variable depending on the situation. Then, the route setting unit searches for whether there is a hydrogen ST such that B' ≥ F + D. If not, it notifies that it is impossible to reach with a single stop at a hydrogen ST and ends the search, or it may search for a route that stops at two or more hydrogen STs. On the other hand, when there is a hydrogen ST such that B' ≥ F + D, the route setting unit selects the hydrogen ST with the minimum Y among the plurality of hydrogen ST candidates and determines it as the first hydrogen station. Then, the route from the current location to the destination is changed to a route passing through the first hydrogen station and determined as the guidance route.

[0038] FIG. 4 is a diagram showing an example of a case where the condition is satisfied without stopping at a hydrogen ST, a case where the condition is not satisfied when stopping, and a case where the condition is satisfied when guiding a route that satisfies the condition of B ≥ F + D or B' ≥ F + D. On the premise that the current location and the time of stopping at a hydrogen ST are in a full hydrogen state of 100, assuming that the minimum required hydrogen amount F to reach the second hydrogen station from the destination is at least 30 hydrogen, and the planned hydrogen usage amount D to be used at the destination is at least 20 hydrogen, a total of 50 is left as the required hydrogen amount C (C = F + D) required at the time of reaching the destination. (i) Route 1 in Case 1 is a case in which the condition B≧F+D is met without hydrogen refueling, (ii) Route 1 in Case 2 is a case in which the condition B≧F is not met without hydrogen refueling, Route 2 is a case in which hydrogen is refueled but the condition B'≧F is not met (a case in which hydrogen is wasted due to a nearby hydrogen ST), Route 3 is a case in which hydrogen is refueled and the condition B'≧F is met but the condition B'≧F+D is not met, and Route 4 is a case in which hydrogen is refueled and the condition B'≧F+D is met. In the example of Figure 2, when stopping at a hydrogen station, routes 3 and 4 in (ii) Case 2 both satisfy the conditions, but in the example of Figure 4, only route 4 in (ii) Case 2 satisfies the conditions, so route 4 is selected.

[0039] (Other embodiments) If you do not set a destination and are driving without paying attention to the amount of hydrogen remaining, you may find that you are low on hydrogen before you know it and are already unable to reach the nearest hydrogen station (or that you still have hydrogen remaining but are unable to get to the hydrogen station). Therefore, even if a destination has not been set, the distance between the nearest hydrogen station and the current location can be calculated in the background, and a hydrogen station guidance caution can be displayed on the display before there is a possibility that the vehicle will not be able to reach the nearest hydrogen station.

[0040] FIG. 5 is a flowchart showing an example of guidance performed by the navigation device of the present disclosure when a destination has not been set. First, the acquisition unit acquires the current location. Thereafter, the acquisition unit acquires the current amount of hydrogen A and the amount of hydrogen consumption X that is expected to be consumed up to the nearest hydrogen ST. The calculation unit calculates the expected remaining hydrogen amount B (B=AX) upon arrival at the nearest hydrogen ST, and the required hydrogen amount C (which may be a margin to ensure that hydrogen does not run out upon arrival) required upon arrival at the destination. The path setting unit determines whether the estimated remaining hydrogen amount B is smaller than the required hydrogen amount C (B

Claims

1. A navigation device that is mounted on a fuel cell vehicle having a fuel cell that uses hydrogen gas as a fuel gas and performs route guidance for the fuel cell vehicle, An acquisition unit that acquires a current amount of hydrogen A and an amount of hydrogen consumption X that is expected to be consumed up to the destination; an identification unit that identifies a first hydrogen station that is present in the vicinity of a route from a current location to the destination and a second hydrogen station that is closest to the destination; A calculation unit that calculates an expected remaining amount of hydrogen B (B=A-X) upon arrival at the destination and a required amount of hydrogen C upon arrival at the destination; A path setting unit, when the estimated remaining amount B of hydrogen is smaller than the required amount C of hydrogen (B<C), the route setting unit changes the route from the current location to the destination to a route that passes through the first hydrogen station; The required amount of hydrogen C is a minimum required amount of hydrogen F required to reach the second hydrogen station from the destination, The acquisition unit acquires a planned hydrogen usage amount D to be used at the destination, the route setting unit performs route search so as to leave a minimum required amount of hydrogen F for reaching the second hydrogen station from the destination and the planned amount of hydrogen usage D; The navigation device is characterized in that, when a predetermined location is set when the destination is set, the route setting unit issues a command to confirm whether or not hydrogen is required at the destination.

2. 2. The navigation device according to claim 1, wherein the planned hydrogen usage amount D is a value that is statistically calculated from a user input value or a destination attribute.

3. 3. The navigation device according to claim 1, wherein the route setting unit issues an alarm when there is a risk that the amount of hydrogen F required to reach the second hydrogen station from the destination will fall below a minimum amount F required during use of hydrogen at the destination.

4. A navigation device as described in any one of claims 1 to 3, wherein when the planned hydrogen usage amount D is a value statistically calculated from the destination attributes, the acquisition unit compares the amount of hydrogen consumption E actually consumed at the destination with the planned hydrogen usage amount D to calculate an error, accumulates data on the error, and corrects the planned hydrogen usage amount D in accordance with the error.

5. 5. The navigation device according to claim 1, wherein, in the route change, the route setting unit selects, from among the two or more first hydrogen stations, a hydrogen station that has a minimum amount of hydrogen consumption Y that is expected to be consumed from the current location to the destination via the hydrogen station.

Images