Aircraft control device and method

Abstract

To implement more secure flight control of a flying body while suppressing an increase in cost.SOLUTION: A flying body control device 100 for performing flight control onto a flying body 200 comprises: a flight plan preparation section 110 which acquires flight related information indicating conditions relating to a flight of the flying body 200, identifies a flight continuation level indicating a flight capacity in the flying body 200 in accordance with the flight related information, identifies a limit level relating to flight in a flight air space corresponding to the flight continuation level, identifies a flyable area meeting the limit level and uses the flyable area to create a flight plan including a flight route of the flying body; and a guidance control section 130 which performs flight control over the flying body using the flight plan.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to an aircraft control device and an aircraft control method for controlling an aircraft using an aircraft flight plan.

Background Art

[0002] Currently, technologies for controlling aircraft, such as unmanned aircraft like drones, have been proposed. Also, although the flight areas of aircraft are severely restricted, they have been tending to be relaxed in recent years. In order to relax the flight area restrictions of aircraft while ensuring safety, it is important to improve the reliability in the flight of aircraft.

[0003] Regarding this improvement in reliability, Patent Document 1 has been proposed. In Patent Document 1, in order to enable an aircraft to land safely before reaching its destination, the flightable distance of the aircraft 20 is calculated from the remaining battery level, and then the information generation unit 280 determines, among a plurality of landing candidate points stored in the information storage unit 270, a landing candidate point located within the flightable distance (or a value obtained by multiplying the flightable distance by a predetermined coefficient less than 1) from the current position calculated by the control unit 260 as the point where the aircraft 20 should land. A method of selection is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] According to Patent Document 1, when the battery level decreases, the aircraft can be made to land safely before reaching its destination, but it is extremely difficult to address all sudden malfunctions that may occur in the aircraft. Addressing all of these malfunctions is extremely difficult, and attempting to do so may lead to increased costs related to the aircraft and a more complex configuration. Furthermore, relaxing regulations without improving the reliability of the aircraft increases the risk of accidents. Therefore, the present invention aims to achieve safer aircraft flight control while suppressing cost increases. [Means for solving the problem]

[0006] To achieve the above objective, the present invention creates a flight plan that includes a flight path that satisfies the restriction level of the airspace corresponding to the flight continuity level indicating the flight capability of the aircraft. More specifically, the present invention provides an aircraft control device that performs flight control on an aircraft, which acquires flight-related information indicating the flight conditions of the aircraft, identifies the flight continuity level indicating the flight capability of the aircraft according to the flight-related information, and identifies the restriction level for the airspace corresponding to the flight continuity level. From the unit areas obtained by dividing the aforementioned flight airspace into multiple units, a unit area with a restriction level more relaxed than the aforementioned restriction level is selected. The aforementioned limit level of Sufficient flight area as Identify, The continuous or adjacent range from the departure position to the arrival position of the aforementioned aircraft. The aforementioned flightable area By combining these, a flight path candidate is identified, and if multiple flight path candidates are identified, the flight path candidate with the smallest representative value of the restriction level of the unit area constituting the flight path candidate is selected. Flight path of the aforementioned aircraft The identified flight path The present invention includes a flight plan creation unit that creates a flight plan including the aircraft, and a guidance control unit that performs flight control of the aircraft using the flight plan. The present invention also includes an aircraft control method using this aircraft control unit. [Effects of the Invention]

[0007] According to the present invention, it is possible to achieve safer flight control of aircraft while suppressing cost increases. [Brief explanation of the drawing]

[0008] [Figure 1]System configuration diagram including the aircraft control device 100 in one embodiment of the present invention [Figure 2] Functional block diagram of the aircraft control device 100 in one embodiment of the present invention. [Figure 3] A diagram showing the airspace divided by multiple voxels and its flight path in Example 1. [Figure 4] Flowchart showing the flight control processing flow in Example 1 [Figure 5] Figure showing flight plan 330 in Example 1 [Figure 6] A diagram showing the airspace divided by the corridor and its flight path in Example 2. [Figure 7] Figure showing flight plan 330 in Example 2 [Figure 8] A schematic diagram showing the flyable area information 310 in Example 3. [Figure 9] This figure illustrates the procedure for identifying a flight path using the flyable area information 310 in Example 3. [Figure 10] Figure showing flight continuity level information 320 in Example 4, where the flight continuity level is set to three levels. [Figure 11] Figure showing flight continuity level information 320 in Example 4, where the flight continuity level is set to three levels. [Figure 12] Figure 4 shows the flight area information 310 in which the flight airspace restriction levels are set to three stages. [Figure 13] Figure showing flight continuity level information 320 in Example 4, where the flight continuity level is set to four levels. [Figure 14] Figure 4 shows the flight area information 310 in which the flight airspace restriction levels are set to four stages. [Figure 15] The first graph shows the relationship between lift and failure occurrence and the possibility of continuing flight in Example 4. [Figure 16] The second graph shows the relationship between lift and failure occurrence and the possibility of continuing flight in Example 4. [Figure 17]The third graph showing the relationship between lift force and occurrence of failure and the possibility of flight continuation in Example 4 [Figure 18] The fourth graph showing the relationship between lift force and occurrence of failure and the possibility of flight continuation in Example 4 [Figure 19] The second graph showing the relationship between lift force and occurrence of failure and the possibility of flight continuation in Example 4 [Figure 20] The figure showing flight continuation level information 320 including the flight continuation level according to the failure rate in the airframe of the aircraft 200 in Example 5 [Figure 21] The figure showing flight continuation level information 320 indicating the flight continuation level according to the failure rate in the airframe of the aircraft 200 in Example 5 [Figure 22] The figure showing the redundant aircraft 200 in Example 5 [Figure 23] The figure showing flight continuation level information 320 indicating the flight continuation level according to the flight ability and failure rate in the airframe of the aircraft 200 in Example 5 [Figure 24] The figure showing flight continuation level information 320 indicating the flight continuation level according to the flight ability, failure rate and security level in the airframe of the aircraft 200 in Example 5 [Figure 25] The figure showing the security level table in Example 5 [Figure 26] The figure showing the flightable area information 310 in Example 5 [Figure 27] The figure for explaining the concept of flight continuation level information 320 considering the influence of wind in Example 6 [Figure 28] The figure showing flight continuation level information 320 considering the influence of wind on the aircraft 200 in Example 6 [Figure 29] The figure showing flight continuation level information 320 considering the airframe weight of the aircraft 200 in Example 6 [Figure 30] It is a system configuration diagram of a flight control system including an implementation example of the flight control device 100 in Example 7

Modes for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. First, Figure 1 is a system configuration diagram including the aircraft control device 100 in this embodiment. In Figure 1, the aircraft control device 100 controls the aircraft 200 using flightable area information 310 and flight continuation level information 320. More specifically, the aircraft control device 100 creates a flight plan 330 including the flight path of the aircraft 200 using the flightable area information 310 and flight continuation level information 320, approves and registers the flight path, and guides and controls the aircraft 200 according to the flight path. For this purpose, the aircraft control device 100 includes a flight plan creation unit 110, a flight plan confirmation unit 120, and a guidance control unit 130, as shown in the functional block diagram of Figure 2.

[0010] Furthermore, the aircraft control device 100 includes an input unit and an output unit for inputting and outputting various information and signals. These may be implemented as an input / output unit or a communication unit. In addition, the aircraft control device 100 may have a storage unit for storing flight area information 310, flight continuation level information 320, and flight plan 330, or it may be configured to be connected to such a unit.

[0011] First, the flight plan creation unit 110 uses flight-related information indicating flight conditions for the aircraft, such as flyable area information 310 and flight continuity level information 320, to identify the flight path from the starting point to the destination, and creates a flight plan 330 that includes this path.

[0012] Furthermore, the flight plan confirmation unit 120 confirms the created flight plan 330. To this end, the flight plan confirmation unit 120 performs an approval process for the created flight plan 330 and stores the approved flight plan 330 in the storage unit.

[0013] Furthermore, the guidance control unit 130 uses the created flight plan 330 to perform flight control on the aircraft 200. For this purpose, for example, the guidance control unit 130 creates control signals for flight control and outputs these control signals to the aircraft 200. As a result, the aircraft 200 flies according to the flight plan 330.

[0014] This concludes the description of this embodiment, and now we will describe various examples illustrating more specific aspects of the present invention. [Examples]

[0015] In Example 1, a flight path is identified for an airspace divided into multiple voxels. Figure 3 shows the airspace divided by multiple voxels and its flight path in Example 1. As shown in Figure 3, the aircraft 200 flies from left to right in the diagram. That is, it flies in the z-axis direction, starting from voxel (1,1,0) and passing through each voxel (1,1,z). Therefore, the flight path can be represented as a set of voxels occupied by the aircraft 200 as time progresses. In Example 1, the flight path is identified as a set of voxels occupied by the aircraft 200, and a flight plan 330 including this is created. The processing flow of this example will be described below. Note that this processing flow is common to each example from Example 2 onwards.

[0016] Figure 4 is a flowchart showing the flight control processing flow in Embodiment 1. First, in step S1, the input unit of the aircraft control device 100 acquires flight-related information indicating conditions related to the flight of the aircraft 200. Flight-related information includes, for example, fuel and battery levels, weight, and weather conditions. The input unit may also accept flight-related information input from the user, or it may read flight-related information stored in the memory unit.

[0017] Furthermore, in step S2, the flight plan creation unit 110 identifies the flight continuation level corresponding to the flight-related information acquired in step S1 from the flight continuation level information 320. Here, the flight continuation level information 320 is information indicating the flight capability, which is the content of the flight that the aircraft can perform, for each flight continuation level. Therefore, in step S2, the flight plan creation unit 110 searches for the flight continuation level information 320 that includes the flight capability corresponding to the flight-related information and identifies the flight continuation level indicated by it. In this embodiment and in embodiments 3 and 4 described later, a multi-stage flight continuation level with three or more stages is used as the flight continuation level.

[0018] Furthermore, in step S3, the flight plan creation unit 110 identifies the restriction level of the flight airspace corresponding to the flight continuation level identified in step S2 from the flight-permitted area information 310. Here, the flight-permitted area information 310 is information that indicates the content of flight restrictions based on the positional conditions of the flight airspace for each restriction level. For this reason, the stricter the restriction level (for example, the larger the numerical value), the higher the flight continuation level, i.e., the flight capability required. Thus, in this embodiment, the flight continuation level and the restriction level have a corresponding relationship. For example, if the flight continuation level and the restriction level are both the same value, it can be determined that they are applicable. For this reason, it is desirable that the flight continuation level and the restriction level each have the same level. The positional conditions of the flight airspace refer to conditions indicating the distance and relative position from any object such as important facilities.

[0019] Therefore, in this step, the flight plan creation unit 110 uses this correspondence to identify a restriction level corresponding to the flight continuation level, for example, a restriction level with the same value as the flight continuation level.

[0020] Furthermore, in step S4, the flight plan creation unit 110 identifies a flyable area that satisfies the restriction level identified in step S3 using the flyable area information 310. Here, a flyable area that satisfies the restriction level means that it consists of a unit of airspace in which the aircraft 200 can fly, and which has a restriction level with a predetermined relationship to the restriction level identified in step S3. The predetermined relationship includes the restriction level being less than or equal to the restriction level identified in step S3, that is, being relaxed.

[0021] Furthermore, in Example 1, the airspace is divided into multiple voxels. Therefore, the flight planning unit 110 identifies the positional conditions of each voxel in the target airspace. The flight planning unit 110 also identifies the restriction levels corresponding to the identified positional conditions using the flyable area information 310. The flight planning unit 110 then extracts the restriction levels from among the identified restriction levels that are less than or equal to the restriction level identified in step S3. As a result, the flight planning unit 110 extracts voxels in which the restriction level is more relaxed than the restriction level identified in step S3.

[0022] Furthermore, in step S5, the flight planning unit 110 identifies a flight path by combining the extracted voxels, i.e., the flyable area. To do this, the flight planning unit 110 identifies consecutive or adjacent voxels from the departure position to the arrival position included in the flight-related information, and identifies candidate flight paths composed of these voxels. If there are multiple candidate flight paths, the flight planning unit 110 evaluates them to identify a flight path. For this evaluation, conditions such as short distance, minimum restriction level, or a combination thereof can be used. Here, when using restriction levels for this evaluation, representative values ​​such as the sum of the restriction levels of each voxel constituting the flight path, i.e., each unit of airspace, will be used.

[0023] Furthermore, if there are no flight path candidates, the flight plan creation unit 110 outputs to the output unit that flight is not possible and terminates the process. The flight plan creation unit 110 may also output to the output unit information prompting the user to create a flight plan.

[0024] In this step, the flight plan creation unit 110 performs processing on each voxel of the identified flight path, such as adding the passage time and identification information to identify the target aircraft 200, and creates a flight plan 330.

[0025] Furthermore, in step S6, the flight plan confirmation unit 120 confirms the flight plan created in step S5. To do this, the flight plan confirmation unit 120 outputs the flight plan created in step S5 to the output unit. Then, if the input unit receives approval input from the user, the flight plan confirmation unit 120 determines that the created flight plan 330 has been approved. The flight plan confirmation unit 120 then registers the approved flight plan 330 in the storage unit.

[0026] Furthermore, in step S7, the guidance control unit 130 creates a control signal corresponding to the flight plan 330 determined in step S6. The guidance control unit 130 then outputs this control signal to the aircraft 200 via the output unit. As a result, the aircraft 200 will fly according to the flight plan 330. The guidance control unit 130 also performs its processing so that the aircraft 200 flies within the transit time (including departure time) included in the flight plan 330.

[0027] In this processing flow, for identifying flight paths or creating flight plans, multiple flight paths or flight plans may be identified and created in advance, and the flight plan confirmation unit 120 or the guidance control unit 130 may select the one that corresponds to the aircraft 200 to be controlled. The flight plan confirmation unit 120 may use the evaluation method of step S5, such as the use of restriction levels, for this selection.

[0028] Furthermore, the flight plan creation unit 110 may identify or create these for each flight of the aircraft 200. In addition, the flight plan creation unit 110 may identify and create multiple flight paths or flight plans in advance, and if there are no flight paths or flight plans that correspond to the aircraft 200 to be controlled, it may identify or create new ones. This concludes the explanation of Figure 4, and the flight plan 330 created in this processing flow will now be explained.

[0029] Figure 5 shows the flight plan 330 in Example 1. In Figure 5, the flight plan 330 is represented as a set of voxels occupied by the aircraft 200 at each time point. Specifically, the flight plan 330 is represented as a set of date and time 331, voxel ID 332, aircraft ID 333, and authentication signature 334. In other words, it indicates that "aircraft ID 333" occupies "voxel ID 332" at the time "date and time 331". Note that voxels are represented by their X, Y, and Z coordinates.

[0030] Furthermore, the example in Figure 5 shows that as time progresses, the aircraft 200 occupies voxels (1,1,0), (1,1,1), (1,1,2), (1,1,3), (1,1,4), (1,1,5), (1,1,6), (1,1,7), (1,1,8), (1,0,8), (1,0,9), (0,0,9), and (0,0,10) from 2022 / 12 / 12 00:00:00 to 2022 / 12 / 12 00:00:00. In other words, the aircraft 200 will fly along the flight path indicated by the set of these voxels. At 00:00:07 and 00:00:08 on 12 / 12 / 2022, aircraft 200 occupies two adjacent voxels: (1,1,8), (1,0,8), (1,0,9), and (0,0,9). This means that for aircraft to avoid collisions, the occupation of voxels by aircraft 200 must be spatially and temporally exclusive. In other words, it is necessary that "Date and Time 331" and "Voxel ID 332" are assigned to each aircraft so as not to overlap. In this application, occupation means that, in order for aircraft 200 to pass through the voxel in question, the entry of other aircraft into the voxel in question and / or adjacent voxels is suppressed. As described above, in Example 1, a voxel is used as an example of a unit airspace. This concludes the explanation of Example 1. [Examples]

[0031] In Example 1, the flight path was created using a collection of voxels, but in Example 2, the flight path is created as a collection of corridors (aerial walkways). Figure 6 shows the airspace divided by the corridors and its flight path in Example 2. As shown in Figure 6, the aircraft 200 flies from left to right in the diagram. That is, it flies from corridor 13 through corridor 23.

[0032] In Example 2, the aircraft control device 100 creates a flight plan 330 and controls the aircraft 200 according to the flowchart shown in Figure 4, similar to Example 1. However, a corridor is used instead of voxels in steps S4 and S5.

[0033] As a result, in Example 2, the flight plan 330 shown in Figure 7 is created. As shown in Figure 7, the flight plan 330 in Example 2 is represented as a set of date and time 331, corridor ID 332', aircraft ID 333, and authentication signature 334. In other words, it indicates that "aircraft ID 333" occupies "corridor ID 332'" at the time "date and time 331". In this example, it also indicates that aircraft 200 occupies corridor 13 at 2022 / 12 / 12 00:00:00 and occupies corridor 13 at 2022 / 12 / 12 00:00:10.

[0034] In Example 2, the flight plan confirmation unit 120 writes an authentication signature 334 each time the flight plan 330 is created or updated, provided that the "Date and Time 331" and "Voxel ID 332" or "Date and Time 331" and "Corridor ID 332'" do not overlap. Here, "not overlapping" means that it is not assigned to multiple aircraft IDs 333. The flight plan confirmation unit 120 may use a specific code as the authentication signature 334, perform a sum check of information such as Date and Time 331, Corridor ID 332', and Aircraft ID 333, or generate it according to a predetermined generation polynomial.

[0035] Based on the above, the flight plan confirmation unit 120 can determine whether the flight plan is valid or not based on the match or mismatch between the value of the authentication signature 334 and the expected value given from information such as the date and time 331, corridor ID 332', and aircraft ID 333. If the result of this determination is that the plan is valid, the flight plan confirmation unit 120 may consider the flight plan 330 to be approved. This process can also be applied to Example 1. In this case, the flight plan confirmation unit 120 will use voxel ID 332 instead of corridor ID 332'.

[0036] As described above, the guidance control unit 130 controls the flight of the aircraft 200 using the flight plan 330. Specifically, the guidance control unit 130 creates control signals according to the date and time 331, corridor ID 332', and aircraft ID 333 registered in the flight plan 330. The guidance control unit 130 then outputs control signals to the aircraft 200. It is also desirable for the guidance control unit 130 to create and output corrective control signals if there is a risk of deviation from the flight path included in the flight plan 330. These processes can also be applied to Embodiment 1. In this case, the guidance control unit 130 will use voxel ID 332 instead of corridor ID 332'.

[0037] This concludes the explanation of Example 2, but Examples 1 and 2 can be combined. In other words, voxels and corridors, which represent unit airspace, can be used in combination. For example, the aircraft control device 100 can represent airspace near an airport or near a branching point of a flight path with voxels as shown in Figure 3, and the flight path connecting them with corridors as shown in Figure 6, and create flight paths and perform flight control. In this case, it is assumed that the aircraft control device 100 will share the fields for voxel ID 332 and corridor ID 332' in the flight plan 330, and add an identifier to indicate whether it represents a voxel or corridor ID, which represent unit airspace. For example, "V" is prefixed to voxel IDs, and "C" is prefixed to corridor IDs. As described above, in Example 2, corridors are used as an example of unit airspace. [Examples]

[0038] Next, as Example 3, an example of flyable area information 310 will be described. Figure 8 is a schematic diagram showing the flyable area information 310 in Example 3. Figure 8 shows that it consists of the coordinates of important facilities 311, 312, and 313 on the airspace map, and the coordinates of the corresponding Level L1 no-fly zones (314, 315, 316)...Level Lx no-fly zones (317, 318, 319). Note that the coordinates of the Level L1 no-fly zones (314, 315, 316)...Level Lx no-fly zones (317, 318, 319) may also be represented as a set of voxel IDs.

[0039] The above shows an example of setting no-fly zones on the airspace map in advance. However, the flyable area information 310 may also be generated from the coordinate information of important facilities on the airspace map, and from the flight airspace restriction information as shown in Figures 12, 14, and 25 described later, to determine the no-fly zones (coordinates) at each level. The flyable area information 310 may be created by the flight plan creation unit 110, or it may be created by other devices or by manual input by the user.

[0040] Here, we will explain the concept of determining the flight path using the flyable area information 310 (step S5 in Figure 4). Figure 9 is a diagram illustrating the procedure for determining the flight path using the flyable area information 310 in Example 3. In Figure 9, the aircraft 200 is scheduled to fly from point A to point B. This is included in the flight-related information. In this case, depending on the flight continuity level, a predetermined distance (X1~X4 [m], where X1≦X2≦X3≦X4) must be maintained between the aircraft 200 and important facilities, etc., located between point A and point B.

[0041] Therefore, the flight planning unit 110 selects flight paths 4, 3, 2, and 1 in order of increasing flight continuity level. As a result, when flying from point A to point B, the aircraft 200 with a high flight continuity level can fly a shorter flight path. In other words, the flight planning unit 110 identifies the flight paths with small numerical values, such as flight paths 0 and 1 in the figure, as the flight paths for the aircraft 200 with a high flight continuity level. Here, the aircraft control device 100 may be configured to display the contents of Figure 9 via an output unit. In particular, selecting flight path 0, which flies over important facilities (including flights for maintenance and inspection), is limited to cases where the flight continuity level is extremely high, the failure rate is low, and the security level is high. Note that this flight path procedure can also be applied to other embodiments. [Examples]

[0042] Next, as Example 4, we will describe an example where the flight continuity level of the flight continuity level information 320 has three or more levels. By setting the flight continuity level in this way, cases where flight is possible under certain conditions arise between flight possible and flight impossible, creating room for optimization under the conditions in which flight is possible. Therefore, in this implementation, the flight continuity level in the flight continuity level information 320 is set to three or more levels (3 levels, 4 levels, 5 levels).

[0043] Figures 10 and 11 show the flight continuation level information 320 in Example 4, where the flight continuation level is set to three levels. First, Figure 10 shows the flight continuation level information 320, where Level 1 is the flight continuation level at which the aircraft can fly to the destination, Level 2 is the flight continuation level at which the impact upon landing can be mitigated, and Level 3 is the flight continuation level that does not fall into either category. Of these, Level 1, the "flight continuation level at which the aircraft can fly to the destination," is the level at which the aircraft 200 can maintain a lift greater than its own weight to the destination, as shown in Figure 15, in terms of the output level and output duration. In order to achieve this Level 1, the aircraft 200 needs to have redundancy to prepare for failures in the propulsion mechanism and the mechanism that generates lift. Figure 15 is the first graph showing the relationship between lift and failure occurrence and the possibility of flight continuation in Example 4.

[0044] Furthermore, Level 2, the "flight continuation level that can mitigate impact upon landing," indicates a level where "sufficient output is possible to mitigate impact upon landing," as shown in Figures 16 and 19. Here, Figures 16 and 19 are second graphs showing the relationship between lift and failure occurrence and the possibility of continuing flight in Example 4. First, expressed in terms of the output level of the aircraft 200, as shown in Figure 19, it is a level where "sufficient output is possible to mitigate impact upon landing." Here, "mitigating impact" means not only preventing damage to the aircraft 200 itself, but also preventing damage to buildings, structures, people, etc. on the ground. For example, this can be achieved by descending by autorotation in a helicopter, which is a type of aircraft 200, or by mitigating the descent speed by drag such as a parachute provided on the aircraft 200. In addition, in the case of an electric aircraft, which is a type of aircraft 200, it is not possible to generate enough lift to support the freedom of the electric aircraft, but it is required that it be able to generate enough lift to reduce the rate of descent.

[0045] Furthermore, expressing Level 2 as output duration, as shown in Figure 16, it is the level where "it is possible to maintain lift exceeding the aircraft's own weight for a sufficient time to mitigate the impact upon landing." This includes, for example, applying a collective flare (increasing the rotor blade pitch to convert the rotational energy of the rotor blades into lift) at the moment of landing during autorotation descent by a helicopter, which is a type of aircraft 200. It also includes inflating the airbags on the underside of the aircraft 200 to absorb and mitigate the impact of landing.

[0046] Furthermore, in the case of electric aircraft, another type of aircraft 200, Level 2 requires that it cannot generate enough lift to support the aircraft's freedom for an extended period. However, it is required that it be able to generate enough lift to reduce the rate of descent for a short time at the moment of landing.

[0047] Level 3 is a flight continuation level that does not fall under either Level 1 or Level 2. This will be explained later when describing Figure 11.

[0048] Next, we will explain the flight continuation level information 320 shown in Figure 11. In the flight continuation level information 320 shown in Figure 11, Level 1 is the flight continuation level at which it is possible to fly to the destination, Level 2 is the flight continuation level at which it is possible to land at an alternative landing site, and Level 3 is the flight continuation level that does not fall into either category. If we express Level 2 shown in Figure 11 in terms of output level, it indicates that it is possible to generate enough power to land at an alternative landing site. Furthermore, if we express this in terms of output duration, it is the level at which it is possible to maintain a lift greater than the aircraft's own weight until landing at an alternative landing site, as shown in Figure 17. Here, Figure 17 is a third graph showing the relationship between lift and failure occurrence and the possibility of flight continuation in Example 4.

[0049] Furthermore, Level 3 is a flight continuation level that does not fall under either Level 1 or Level 2. As shown in Figure 18, Level 3 is the level at which the aircraft cannot generate lift exceeding its own weight after a malfunction occurs. Figure 18 is a fourth graph showing the relationship between lift and malfunction occurrence and the possibility of continuing flight in Example 4.

[0050] Furthermore, the flight continuation level is associated with the flight airspace restriction level. In other words, the restriction level in Example 4 is set in three stages, similar to the flight continuation level. The restriction level in Example 4 will be described below. Figure 12 shows the flightable area information 310 in Example 4, where the flight airspace restriction level is set in three stages.

[0051] In Figure 12, restriction level 1 corresponds to flight continuation level 1. Restriction level 1 is a flight restriction that allows flight only within x1 [m] of critical infrastructure, and there are no restrictions on distance from densely populated areas or from third parties or third-party objects.

[0052] Furthermore, in Figure 12, restriction level 2 corresponds to a flight continuation level (level 2) where landing at an alternative landing site is possible or impact mitigation is possible upon landing. In this case, the flight restriction is that flight is only permitted within x2 [m] of critical infrastructure and within y1 [m] of densely populated areas, and there are no restrictions on distance from third parties or third-party objects.

[0053] Furthermore, restriction level 3, which does not meet any of the above conditions, indicates that flight is permitted only at a distance of x4 [m] from critical facilities, y3 [m] from densely populated areas, and z2 [m] from third parties or third-party objects within densely populated areas. Note that under current Japanese law, restrictions on flight airspace are not categorized into levels as in this example, and it is believed that all are classified as the lowest restriction level 3. In this case, x4 = 300m (Law Prohibiting Flights of Small Unmanned Aircraft, etc.) and z2 = 30m (Aviation Law). The above describes the horizontal distances that must be maintained, but similarly, vertical and height distances that must be maintained can also be defined for each restriction level.

[0054] Next, we will explain an example where the flight continuity level information 320 has four levels. Figure 13 shows the flight continuity level information 320 in Embodiment 4, where the flight continuity level is set to four levels. In Figure 13, Level 1 is set as the flight continuity level at which it is possible to fly to the destination, Level 2 is set as the flight continuity level at which it is possible to land at an alternative landing site, Level 3 is set as the flight continuity level at which the impact upon landing can be mitigated, and Level 4 is set as the flight continuity level that does not fall under any of the above. Then, in correspondence with this flight continuity level information 320, the flyable area information 310, which has four restriction levels, is used.

[0055] Figure 14 shows the flight area information 310 in Example 4, where the flight airspace restriction levels are set to four stages. In Figure 14, the flight restriction at restriction level 1 is that flight is only permitted at a distance of x1 [m] or more from critical facilities, and there are no restrictions on distance from densely populated areas or from third parties or third objects.

[0056] Furthermore, flight restrictions at restriction level 2 allow flights only within x2[m] of critical infrastructure and within y1[m] of densely populated areas, with no restrictions on distance from third parties or third objects. Similarly, flight restrictions at restriction level 3 allow flights only within x4[m] of critical infrastructure, within y2[m] of densely populated areas, and within z1[m] of third parties or third objects from densely populated areas. Finally, flight restrictions at restriction level 4, which do not meet any of the above criteria, allow flights only within x4[m] of critical infrastructure, within y3[m] of densely populated areas, and within z2[m] of third parties or third objects from densely populated areas. [Examples]

[0057] Next, we will describe Example 5, which uses flight continuation levels corresponding to the failure rate. Figure 20 shows the flight continuation level information 320 indicating the flight continuation level according to the failure rate of the aircraft 200 in Example 5. In Example 5, flight continuation level information 320 showing five levels of flight continuation is used. Therefore, using the failure rate is merely one example, and other flight capabilities may be used. In Figure 20, levels 1a, 1b, 2, and 3 correspond to the safety levels SIL (Safety Integrity Level) 4, 3, 2, and 1 specified in the functional safety standard (IEC 61508), respectively. In other words, the failure rate decreases in the order of levels 1a to 4, and therefore the flight capability increases in this order. In this example, flightable area information 310 indicating the restriction levels corresponding to these levels 1a to 4 is used.

[0058] Next, a modified example of Embodiment 5 using a flight continuation level corresponding to the redundancy of the aircraft 200 will be described. Figure 21 is a diagram showing the flight continuation level information 320 in Embodiment 5, which indicates the flight continuation level according to the redundancy of each part of the aircraft 200. In Figure 21, the failure rate of the aircraft 200 and the redundancy of each part (components constituting the aircraft 200) are shown for each level. Here, the parts constituting the aircraft 200 include sensors, flight controllers, ESCs (Electronic Speed ​​Controllers), motor windings, motors, and rotors. The flight continuation level information 320 specifies the redundancy of each part as redundant / non-redundant, and the diagnostic coverage (DC) in the case of redundancy. Note that although the battery is not shown as a component of the aircraft 200 in Figure 21, its redundancy may also be included in the flight continuation level information 320. Furthermore, Figure 21 is an example of the flight continuation level information 320 in this embodiment, and the embodiments for achieving the required aircraft reliability (low failure rate) are not limited to this.

[0059] The details of Figure 21 are explained below. In Figure 21, achieving the highest level of safety, Level 1a, requires redundancy of all components and diagnostic coverage exceeding 99%. Furthermore, to achieve diagnostic coverage exceeding 99%, it is necessary to make the flight controllers redundant and to implement self-checking by also making the microprocessors that make up each flight controller redundant.

[0060] To achieve the next level of safety, Level 1b, all components must be redundant, and diagnostic coverage exceeding 90% is required. Furthermore, to achieve Level 2, all parts except the rotor must be redundant, and diagnostic coverage exceeding 90% is required. In addition, the rotor's rotating shaft, which is not redundant, is mechanically connected to a motor redundantly.

[0061] Furthermore, achieving Level 3 requires redundant ESCs and motor windings, resulting in diagnostic coverage exceeding 60%. Motors that are not redundant will have redundant windings, and each winding will be driven by a redundant ESC. Sensors include a GPS receiver; achieving Level 1a requires not only redundant GPS receivers but also other positioning sensors such as an INS (Inertial Navigation System). While GPS receiver redundancy is not required for Level 3, flight can continue even if the GPS signal is lost, thanks to Kalman filtering and dead reckoning (odometric) functions.

[0062] Next, we will describe how the aircraft 200 is made redundant. Figure 22 shows the redundant aircraft 200 in Example 5. In Figure 22, a four-rotor aircraft 200 is shown as an example. Note that when the rotors are made redundant, the four-rotor aircraft 200 will have eight rotors. As shown in Figure 21, depending on the level, there are parts that need to be redundant and parts that do not. For this reason, in Figure 22, parts that need to be redundant depending on the level are shown with dashed lines.

[0063] Using signals from the sensor 202 of the aircraft 200 shown in Figure 22, the flight controller 201 sends rotation speed commands to the ESCs 211-214. The ESCs 211-214 control the current flowing through the motor windings to achieve a predetermined rotation speed according to the rotation speed commands. Rotors 231-244 are attached to the output shafts of the motors 221-224, and the rotation of the motors 221-224 causes the rotors 231-244 to rotate, generating lift. The aircraft 200, which has multiple rotors, does not have a function to control the pitch of the rotors; rather, its attitude and flight direction are controlled by controlling the rotation speed of each rotor.

[0064] Here, sensors 202 can include GPS receivers and attitude sensors. The GPS receiver sends the current position of the aircraft 200 to the flight controller 201, which then controls rotors 231-244 so that the aircraft 200 flies according to the flight path in the flight plan. Furthermore, the attitude sensors also send attitude information of the aircraft 200 to the flight controller 201, which then controls rotors 231-244 so that the aircraft 200 maintains a predetermined attitude suitable for flight.

[0065] Next, another example of the flight continuation level information 320 will be described. Figure 23 shows the flight continuation level information 320 in Example 5, which indicates the flight continuation level according to the flight capability and failure rate of the aircraft 200. In Figure 23, the flight continuation level is the same as the flight continuation level information 320 in Figure 20, but with the added condition of the aircraft's failure rate.

[0066] Figure 24 shows the flight continuation level information 320 for the aircraft 200 in Example 5, indicating the flight capability, failure rate, and flight continuation level according to the security level. In other words, Figure 23 is the flight continuation level information 320 in Figure 22 with the added condition of the security level. Here, as the security level (SL), SL 1 to 4 from the international standard IEC62443-3-3 for control system security can be used. In this case, the security level table shown in Figure 25 can be used. Figure 25 shows the security level table in Example 5. In Figure 25, the security level table classifies the characteristics of countermeasures against attacks (attackers) for each SL.

[0067] Next, we will describe the flightable area information 310 in Example 5, that is, the flightable area information 310 associated with each of the flight continuation level information described above. Figure 26 is a diagram showing the flightable area information 310 in Example 5. In Figure 26, the flightable area information 310 is shown in relation to the flight continuation level information 320 described above, and for each of the five restriction levels set, the restrictions on the flight airspace, which are the content of the restrictions on the location conditions of the flight airspace, are shown. Specifically, in Figure 26, the distance from important facilities such as bases is defined as a location condition for the restrictions on the flight airspace.

[0068] The following describes the restrictions on the airspace when using the flight continuity level information 320 shown in Figure 23 and the flyable area information 310 shown in Figure 26. In the case of flight continuity level 1a, it is possible to fly to the destination, and there are no flight restrictions in the case of an aircraft failure rate of less than 10⁻⁸ [ / hour]. In the case of flight continuity level 1b, it is possible to fly to the destination, and in the case of an aircraft failure rate of less than 10⁻⁷ [ / hour], the flight restriction is limited to a distance of x1 [m] or more from critical facilities, and there are no restrictions on distance from densely populated areas or from third parties or third-party objects.

[0069] Furthermore, at flight continuity level 2, landing at an alternative landing site is possible, and in the case of an aircraft failure rate of less than 10⁻⁶[ / hour], flight restrictions are limited to a distance of x2[m] from critical facilities and y1[m] from densely populated areas, with no restrictions on distance from third parties or third objects. Also, at flight continuity level 3, impact mitigation is possible upon landing, and in the case of an aircraft failure rate of less than 10⁻⁵[ / hour], flight restrictions are limited to a distance of x3[m] from critical facilities, y2[m] from densely populated areas, and z1[m] from densely populated areas to third parties or third objects. At flight continuity level 4, where none of the above conditions are met, in the case of an aircraft failure rate, flight is possible only at a distance of x4[m] from critical facilities, y3[m] from densely populated areas, and z2[m] from densely populated areas to third parties or third objects.

[0070] Next, we will discuss the restrictions on flight airspace using the flight continuity level information 320 shown in Figure 24 and the flyable area information 310 shown in Figure 26. In particular, near critical facilities, there is a risk of the aircraft being hijacked by a cyberattack and used for terrorist attacks. For this reason, the security level of the remote control function of the aircraft 200 and positioning sensors such as GPS receivers, as defined in the flight continuity level information 320 shown in Figure 24, are particularly important indicators.

[0071] Under Flight Continuity Level 1a, if the aircraft is capable of flying to its destination, has a failure rate of less than 10⁻⁸ [ / hour], and is at Security Level 4, there are no flight restrictions. Under Flight Continuity Level 1b, if the aircraft is capable of flying to its destination, has a failure rate of less than 10⁻⁷ [ / hour], and is at Security Level 3, the following flight restrictions apply. These restrictions allow flight only within x1 [m] of critical infrastructure, and there are no restrictions on distance from densely populated areas or from third parties or third-party objects.

[0072] Furthermore, in the case of Flight Continuity Level 2, if landing at an alternative landing site is possible, the aircraft failure rate is less than 10⁻⁶ [ / hour], and the security level is SL 2, the following flight restrictions apply. These restrictions allow flight only within x2 [m] of critical infrastructure and y1 [m] of densely populated areas, with no restrictions on distance from third parties or third-party objects.

[0073] Furthermore, in the case of Flight Continuity Level 3, if impact mitigation is possible upon landing, the aircraft failure rate is less than 10⁻⁵[ / hour], and the security level is SL 1, the following flight restrictions apply. These restrictions mean that flight is only permitted beyond x3[m] from critical facilities, beyond y2[m] from densely populated areas, and beyond z1[m] from densely populated areas to third parties or third objects. In the case of Flight Continuity Level 4, which does not meet any of the above conditions, flight is only permitted beyond x4[m] from critical facilities, beyond y3[m] from densely populated areas, and beyond z2[m] from densely populated areas to third parties or third objects. This concludes the explanation of Example 5. [Examples]

[0074] Next, we will describe Example 6, which uses flight continuity level information 320 that takes into account the effects of wind, which is an example of weather conditions, and the weight of the aircraft 200. Figure 27 is a diagram to explain the concept of flight continuity level information 320 that takes into account the effects of wind in Example 6. In Figure 27, the distances that should be maintained from important facilities, etc., are concentric circles for each flight continuity level when there is no wind. However, when there is wind, it is necessary to take into account that the aircraft will be carried away by the wind and to set a larger distance to be maintained upwind (for example, X'=X+Ku, u: wind speed, K: proportionality constant). In other words, the concentric circles will change from dashed lines to solid lines in Figure 27.

[0075] Here, Figure 28 shows the flight continuation level information 320 considering the effects of wind in Example 6. In this example, the wind resistance characteristics (steady wind, gusts) of the aircraft 200 are used as the flight capability to reflect the effects of wind. Security levels may also be added. A security level may be added to this flight continuation level information 320.

[0076] Next, Figure 29 shows the flight continuation level information 320 considering the aircraft weight of the aircraft 200 in Example 6. The heavier the aircraft, the greater the damage in the event of a collision with another object. Therefore, as shown in Figure 28, in the flight continuation level information 320 of Example 6, the heavier the aircraft, the stricter the flight restrictions will be. In the figure, 1a, 1b, 2, ... 4 shown below the aircraft weight column indicate the flight continuation level. This concludes the explanation of Example 6. [Examples]

[0077] Next, we will describe Embodiment 7, in which the aircraft control device 100 is implemented as a computer. Figure 30 is a system configuration diagram of the aircraft control system, including an implementation example of the aircraft control device 100 in Embodiment 7. In Figure 30, the aircraft control device 100 is connected to the aircraft 200 and the terminal device group 400 via the network 500. For this reason, the aircraft control device 100 can be implemented as a server, also known as a cloud or in-house system, among other computers. Figure 30 shows the hardware configuration of the aircraft control device 100. In other words, the aircraft control device 100 has a processing unit 101, a communication device 102, a memory 103, and a secondary memory device 104, which are connected to each other via a communication path.

[0078] First, the processing unit 101 can be implemented using a processor such as a CPU (Central Processing Unit), and it performs calculations according to the flight control program 105 stored in the secondary memory device 104, which will be described later.

[0079] Furthermore, the communication device 102 has an interface function with other devices. That is, the communication device 102 accepts input from users on the terminal device group 400 and outputs content to be displayed on the terminal device group 400. In this case, the terminal device group 400 and the communication device 102 have the functions of the input and output units described above. The communication device 102 also communicates with the aircraft 200 via the network 500 or directly. More specifically, the communication device 102 outputs control signals to the aircraft 200 according to the calculations of the processing unit 101. The communication device 102 also receives flight status (including flight path and flight attitude) from the aircraft 200.

[0080] Furthermore, the memory 103 and the secondary storage device 104 correspond to the storage units described above. The memory 103 is where the flight control program 105 and information used for processing by the processing unit 101, which are stored in the secondary storage device 104, are loaded. The secondary storage device 104 can be implemented as a so-called storage device. The secondary storage device 104 stores the flight control program 105, the flyable area information 310, the flight continuation level information 320, and the flight plan 330. It is also desirable that the secondary storage device 104 stores other information mentioned above, such as flight-related information. The secondary storage device 104 can be implemented as various storage media such as an external HDD (Hard Disk Drive), SSD (Solid State Drive), or memory card. The secondary storage device 104 may also be implemented as a separate device from the aircraft control device 100, such as a file server.

[0081] Here, the flight control program 105 consists of a flight plan creation module 106, a flight plan confirmation module 107, and a guidance and control module 108, each with its own function. Note that each of these modules may be implemented as an individual program or a combination of some of them. Furthermore, the aircraft control device 100 may be implemented as multiple devices, each with its own function. In addition, the aircraft control device 100 can also be referred to as a control device for the aircraft 200.

[0082] Furthermore, the configuration shown in Figure 2, which performs the same function as each module, is as follows: Flight plan creation module 106: Flight plan creation section 110 Flight plan confirmation module 107: Flight plan confirmation section 120 Induction control module 108: Induction control unit 130 Therefore, the processing unit 101 executes the processing of the flight plan creation unit 110, the flight plan confirmation unit 120, and the guidance control unit 130 shown in Figure 2, in accordance with the flight control program 105. The flight control program 105 can also be stored in a storage medium.

[0083] Furthermore, the terminal device group 400 is a group of terminal devices operated by the user and can be implemented using a computer. The terminal device group 400 will have input and output functions as described above. While this embodiment uses a group of terminal devices, a single terminal device may also be used.

[0084] This concludes the explanation of each embodiment. In each embodiment, it is possible to balance the cost of increased reliability with the resulting benefits to improve efficiency and optimize the cost-effectiveness ratio (for example, shortening the flight path according to the "reliability rank" of the aircraft). In other words, it is possible to balance the cost of increased reliability with the resulting benefits to improve efficiency and optimize the cost-effectiveness ratio (for example, shortening the flight path according to the "reliability rank" of the aircraft).

[0085] Furthermore, the present invention is not limited to the embodiments described above, but can be applied to various applications and modifications. The aircraft 200 also includes not only so-called unmanned aerial vehicles (UAVs) but also manned aircraft, and its power source can be electric or an engine. [Explanation of symbols]

[0086] 100...Aircraft control unit, 110...Flight plan creation unit, 120...Flight plan confirmation unit, 130...Guidance control unit, 200...Aircraft, 310...Flightable area information, 320...Flight continuation level information, 330...Flight plan

Claims

1. In an aircraft control system that performs flight control for an aircraft, Obtain flight-related information indicating the flight conditions of the aforementioned aircraft, In accordance with the aforementioned flight-related information, the flight continuation level indicating the flight capability of the aircraft is identified. Identify the flight restriction levels for the airspace corresponding to the aforementioned flight continuation levels, From the unit areas obtained by dividing the aforementioned flight airspace into multiple units, a unit area with a restriction level relaxed compared to the aforementioned restriction level is identified as a flyable area that satisfies the aforementioned restriction level. A candidate flight path is identified by combining the continuous or adjacent flyable areas from the departure position to the arrival position of the aforementioned aircraft. If multiple flight path candidates are identified, the flight path candidate that has the smallest representative value of the restriction level of the unit area constituting the flight path candidate is identified as the flight path of the aircraft. A flight plan creation unit that creates a flight plan including the identified flight path, An aircraft control device having a guidance control unit that performs flight control of the aircraft using the aforementioned flight plan.

2. In the aircraft control device according to Claim 1, The unit region is a flight control device which is a voxel or corridor that divides the flight airspace into multiple parts.

3. In the aircraft control device according to claim 1, The aforementioned flight plan creation unit identifies multiple flight paths in advance and selects the flight path corresponding to the aircraft using the identified restriction level.

4. In the aircraft control device according to claim 3, The aforementioned flight plan creation unit is an aircraft control device that identifies a new flight path corresponding to the aircraft if there is no flight path corresponding to the aircraft among the multiple flight paths.

5. In the aircraft control device according to claim 1, The aforementioned flight plan creation unit is an aircraft control device that identifies the flight path for each flight of the aircraft.

6. In the aircraft control device according to claim 1, The aforementioned flight continuation level and the aforementioned limitation level are each comprised of three or more levels in the aircraft control device.

7. In an aircraft control method that performs flight control on an aircraft using an aircraft control device, By the Flight Planning Department, Obtain flight-related information indicating the flight conditions of the aforementioned aircraft, In accordance with the aforementioned flight-related information, the flight continuation level indicating the flight capability of the aircraft is identified. Identify the flight restriction levels for the airspace corresponding to the aforementioned flight continuation levels, From the unit areas obtained by dividing the aforementioned flight airspace into multiple units, a unit area with a restriction level relaxed compared to the aforementioned restriction level is identified as a flyable area that satisfies the aforementioned restriction level. A candidate flight path is identified by combining the continuous or adjacent flyable areas from the departure position to the arrival position of the aforementioned aircraft. If multiple flight path candidates are identified, the flight path candidate that has the smallest representative value of the restriction level of the unit area constituting the flight path candidate is identified as the flight path of the aircraft. Create a flight plan that includes the identified flight path, An aircraft control method in which a guidance control unit performs flight control on the aircraft using the flight plan.

8. In the aircraft control method according to Claim 7, The aforementioned unit region is a voxel or corridor that divides the flight airspace into multiple parts, in an aircraft control method.

9. In the aircraft control method according to claim 7, An aircraft control method comprising the flight planning unit identifying multiple flight paths in advance and selecting the flight path corresponding to the aircraft using the identified restriction level.

10. In the aircraft control method according to claim 9, An aircraft control method in which, if the flight plan creation unit does not have a flight path corresponding to the aircraft among the multiple flight paths, a new flight path corresponding to the aircraft is identified.

11. In the aircraft control method according to claim 7, An aircraft control method in which the flight plan creation unit determines the flight path for each flight of the aircraft.

12. In the aircraft control method according to claim 7, The aforementioned flight continuation level and the aforementioned limiting level are each comprised of three or more levels in the aircraft control method.

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