vertical take-off and landing aircraft

Abstract

To provide a technique which restricts the deterioration of ride quality of a vertical takeoff and landing aircraft (VTOL), even when rotations of rotors of the VTOL are simultaneously stopped.SOLUTION: In a vertical takeoff and landing aircraft 10, a plurality of VTOL rotors 20 are separated into a plurality of groups. Each of the VTOL rotors 20 is included in one group. After lift force by a wing (front wing 14, rear wing 16) is generated, a controller sequentially stops the rotations of the plurality of VTOL rotors 20 by a group unit.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a vertical take-off and landing aircraft having multiple VTOL rotors and one or more cruise rotors. [Background technology]

[0002] In recent years, vertical take-off and landing aircraft, so-called VTOL aircraft, have been developed. Some types of VTOL aircraft are equipped with multiple VTOL rotors and one or more cruise rotors. The VTOL rotor generates vertical thrust. The VTOL rotor is mainly used in the take-off and landing process of the VTOL aircraft. The cruise rotor generates horizontal thrust. The cruise rotor is mainly used in the cruising process of the VTOL aircraft.

[0003] Each blade of a VTOL rotor experiences air resistance while the VTOL aircraft is cruising. In other words, the VTOL rotor generates drag while the VTOL aircraft is cruising. It is preferable to reduce the drag caused by the VTOL rotor while the VTOL aircraft is cruising. Patent Document 1 discloses a technique for reducing drag by stopping the rotation of each VTOL rotor while the VTOL aircraft is cruising. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 10,131,426 Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 does not disclose a procedure for stopping the rotation of multiple VTOL rotors. For example, if the rotation of all VTOL rotors is stopped simultaneously, there is a risk that the ride quality of the VTOL aircraft will deteriorate.

[0006] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0007] One aspect of the present invention is a vertical take-off and landing aircraft comprising a plurality of VTOL rotors that generate vertical thrust, one or more cruise rotors that generate horizontal thrust, one or more wings that generate lift in conjunction with the horizontal movement of the aircraft, and a controller that controls the operation of each of the plurality of VTOL rotors and the one or more cruise rotors, wherein the plurality of VTOL rotors are divided into a plurality of groups, each of the VTOL rotors being included in one of the groups, and the controller sequentially stops the rotation of the plurality of VTOL rotors in groups after lift is generated by the wings. [Effects of the Invention]

[0008] According to the present invention, it is possible to suppress deterioration of the ride comfort of a VTOL aircraft. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a top view of a vertical take-off and landing aircraft. [Figure 2] FIG. 2 is a block diagram of a power supply system for a vertical take-off and landing aircraft. [Figure 3] FIG. 3 is a diagram showing the first grouping. [Figure 4] FIG. 4 is a diagram showing the second grouping. [Figure 5] FIG. 5 is a graph showing the change over time in rotational speed of the VTOL rotors in each row in the first grouping. [Figure 6] FIG. 6 is a graph showing the change over time in rotational speed of the VTOL rotors in each row in the first grouping. [Figure 7] FIG. 7 is a graph showing the change over time in rotational speed of the VTOL rotors in each row in the first grouping. [Figure 8] FIG. 8 is a graph showing the change over time in rotational speed of the VTOL rotors in each row in the second grouping. [Figure 9]FIG. 9 is a graph showing the change over time in rotational speed of the VTOL rotors in each row in the second grouping. [Figure 10] FIG. 10 is a graph showing the change over time in rotational speed of the VTOL rotors in each row in the second grouping. [Figure 11] FIG. 11 is a flowchart of the stop process performed by the control unit. [Figure 12] FIG. 12 is a top view of a vertical take-off and landing aircraft of a different type from the vertical take-off and landing aircraft of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] [1 Vertical Take-Off and Landing Aircraft 10 Configuration] 1 is a top view of a vertical take-off and landing aircraft 10. Hereinafter, the vertical take-off and landing aircraft 10 will also be referred to as a VTOL aircraft 10. The VTOL aircraft 10 is, for example, an electric vertical take-off and landing aircraft, a so-called eVTOL aircraft. The VTOL aircraft 10 includes a fuselage 12, a front wing 14, a rear wing 16, two booms 18, eight VTOL rotors 20, and two cruise rotors 22.

[0011] The VTOL aircraft 10 shown in Figure 1 is one example of an aircraft that uses the present invention. The present invention can be used for any aircraft that stops multiple VTOL rotors 20 in a state where lift is generated by fixed wings as the aircraft moves forward.

[0012] The front wings 14 are connected to the front of the fuselage 12. The rear wings 16 are connected to the rear of the fuselage 12. The front wings 14 and the rear wings 16 generate lift as the VTOL aircraft 10 moves forward.

[0013] Of the two booms 18, the boom 18R is disposed on the right side of the fuselage 12. Of the two booms 18, the boom 18L is disposed on the left side of the fuselage 12. Each boom 18 extends in the front-to-rear direction.

[0014] Four motors 40 (FIG. 2) are arranged on the boom 18L in sequence toward the rear. Similarly, four motors 40 are arranged on the boom 18R in sequence toward the rear. The rotation shaft of each motor 40 is connected to the VTOL rotor 20 corresponding to that motor 40. One or more gears may be interposed between the rotation shaft of the motor 40 and the VTOL rotor 20. The axis of the VTOL rotor 20 is parallel to the vertical direction. Alternatively, the axis of the VTOL rotor 20 may be inclined at a predetermined angle relative to the vertical direction. Each VTOL rotor 20 is used in the vertical takeoff process, the takeoff-to-cruise transition process, the cruise-to-landing transition process, the vertical landing process, and the hovering flight process. Each VTOL rotor 20 generates vertical thrust by rotating its propeller.

[0015] As shown in FIG. 1 , the eight VTOL rotors 20 form four rows 24 extending in the left-right direction, i.e., a first row 24a to a fourth row 24d. The first row 24a, the second row 24b, the third row 24c, and the fourth row 24d are arranged in this order from front to rear. Each row 24 is formed by two VTOL rotors 20 that are substantially positioned in the fore-and-aft direction. The first row 24a is formed by a VTOL rotor 20-1L disposed on the left side of the fuselage 12 and a VTOL rotor 20-1R disposed on the right side of the fuselage 12. The second row 24b is formed by a VTOL rotor 20-2L disposed on the left side of the fuselage 12 and a VTOL rotor 20-2R disposed on the right side of the fuselage 12. The third row 24c is formed by a VTOL rotor 20-3L disposed on the left side of the fuselage 12 and a VTOL rotor 20-3R disposed on the right side of the fuselage 12. The fourth row 24d is formed by the VTOL rotor 20-4L disposed on the left side of the fuselage 12 and the VTOL rotor 20-4R disposed on the right side of the fuselage 12.

[0016] Two motors 40 (FIG. 2) are arranged side by side on the fuselage 12. The rotation shaft of each motor 40 is connected to the corresponding cruise rotor 22. A plurality of gears may be interposed between the rotation shaft of the motor 40 and the cruise rotor 22. The axis of the cruise rotor 22 is approximately parallel to the horizontal direction. Each cruise rotor 22 is used during the cruise phase, the transition from takeoff to cruise, and the transition from cruise to landing. Each cruise rotor 22 generates horizontal thrust through the rotation of its propeller.

[0017] [2. Configuration of the power supply system 30] The VTOL aircraft 10 has a power supply system 30 shown in Fig. 2. Fig. 2 is a block diagram of the power supply system 30 of the vertical take-off and landing aircraft 10. The power supply system 30 includes a power storage device 32, a power generation device 34, a converter device 36, an inverter device 38, a motor 40, a sensor group 42, and a control device 44. In Fig. 2, solid arrows indicate power supply lines, and dashed lines indicate signal lines. Note that although the present specification describes a power supply system 30 that includes the power generation device 34, the power supply system 30 does not necessarily have to include the power generation device 34.

[0018] One inverter device 38 and one motor 40 are provided for each rotor (VTOL rotor 20 or cruise rotor 22). On the other hand, one power storage device 32, one power generation device 34, and one converter device 36 are provided for each of a plurality of rotors (VTOL rotors 20 or cruise rotors 22). In other words, the power storage device 32, the power generation device 34, and the converter device 36 are shared by a plurality of power supply systems 30. For example, the same power storage device 32 may be provided for a pair of VTOL rotors 20 (e.g., VTOL rotor 20-1L and VTOL rotor 20-4R) whose torques cancel each other out.

[0019] The power storage device 32 has, for example, a high-voltage battery. The power generation device 34 has a generator. The rotating shaft of the generator is connected to the rotating shaft of, for example, a gas turbine engine. The converter device 36 has a converter circuit. One converter device 36 is provided for one power generation device 34. Primary terminals of the converter circuit are connected to the power generation device 34. Secondary terminals of the converter circuit are connected to the power storage device 32 and the inverter device 38. The converter device 36 can convert AC power output from the power generation device 34 into DC power and output it to the power storage device 32 and the inverter device 38. The converter device 36 can also transform the voltage of the power output from the power generation device 34 and output it to the power storage device 32 and the inverter device 38.

[0020] The inverter device 38 has, for example, a three-phase inverter circuit. The inverter circuit has a plurality of switching elements. A primary terminal of the inverter circuit is connected to the power storage device 32 and the converter device 36. A secondary terminal of the inverter circuit is connected to the motor 40. The inverter device 38 can convert DC power output from at least one of the power storage device 32 and the converter device 36 into AC power and output it to the motor 40.

[0021] The motor 40 is, for example, a three-phase motor. As described above, the rotating shaft of the motor 40 is connected to the hub of one of the rotors (the VTOL rotor 20 or the cruise rotor 22) directly or via one or more gears.

[0022] The sensor group 42 includes sensors provided in the VTOL aircraft 10. For example, the sensor group 42 includes one or more angular velocity sensors. The one or more angular velocity sensors detect at least one of the pitch, roll, and yaw of the VTOL aircraft 10. Each sensor outputs a signal indicating the detected information to the control device 44.

[0023] The control device 44 controls the power supply system 30. The control device 44 may be, for example, a flight controller for the VTOL aircraft 10, or may be a slave controller managed by the flight controller. The control device 44 has a control unit 46, a memory unit 48, and a driver 50.

[0024] The control unit 46 has a processing circuit. The processing circuit may be a processor such as a CPU. The processing circuit may be an integrated circuit such as an ASIC or an FPGA. The processor can perform various processes by executing programs stored in the storage unit 48. At least some of the processes may be performed by electronic circuits including discrete devices.

[0025] The control unit 46 outputs a control signal to the driver 50 to control each motor 40. As a result, the control unit 46 sequentially stops the rotation of the eight VTOL rotors 20 in groups, for example, after lift is generated by the wings (front wings 14, rear wings 16).

[0026] The storage unit 48 has a volatile memory and a non-volatile memory. Examples of the volatile memory include RAM. The volatile memory is used as a working memory for the processor. The volatile memory temporarily stores data required for processing or calculation. Examples of the non-volatile memory include ROM and flash memory. The non-volatile memory is used as a storage memory. The non-volatile memory stores programs, tables, maps, etc. At least a part of the storage unit 48 may be provided in the processor, integrated circuit, etc. as described above.

[0027] The non-volatile memory stores the stopping order (see [4] below) of the multiple VTOL rotors 20. For example, the non-volatile memory stores the correspondence between each group (see [3] below) and each VTOL rotor 20, and the stopping order assigned to each group. Alternatively, the non-volatile memory may store the stopping order assigned to each VTOL rotor 20 instead of the stopping order assigned to each group. In this case, one stopping order is assigned to multiple VTOL rotors 20.

[0028] The driver 50 has a gate driver circuit. The driver 50 outputs an on / off signal to each switching element of the inverter circuit of the inverter device 38 in response to a control signal output from the control unit 46. Furthermore, if the converter device 36 has switching elements, the driver 50 outputs an on / off signal to each switching element of the converter device 36.

[0029] [3 Grouping of multiple VTOL rotors 20] In the present invention, the eight VTOL rotors 20 are divided into a plurality of groups in advance. The groups are divided, for example, according to the distance from the center of gravity G (FIG. 1) of the VTOL aircraft 10 to each VTOL rotor 20. This distance is also called the separation distance. Several examples of grouping patterns are shown below.

[0030] [3-1 First Grouping] FIG. 3 is a diagram showing a first grouping. The distance from the center of gravity G to two VTOL rotors 20 in the same row is the same. Therefore, in the first grouping, two VTOL rotors 20 in the same row constitute the same group. In other words, multiple VTOL rotors 20 that are positioned in the same fore-and-aft direction constitute the same group. For example, in the configuration shown in FIG. 3, the two VTOL rotors 20 in the first row 24a constitute group A. The two VTOL rotors 20 in the second row 24b constitute group B. The two VTOL rotors 20 in the third row 24c constitute group C. The two VTOL rotors 20 in the fourth row 24d constitute group D.

[0031] [3-2 Second Grouping] Fig. 4 is a diagram showing a second grouping. In the second grouping, all VTOL rotors 20 that are spaced the same distance from the center of gravity G form the same group. For example, in the configuration shown in Fig. 4, two VTOL rotors 20 in the first row 24a and two VTOL rotors 20 in the fourth row 24d form group A. Two VTOL rotors 20 in the second row 24b and two VTOL rotors 20 in the third row 24c form group B.

[0032] [3-3 Third Grouping] A pair of VTOL rotors 20 that cancel each other's torque may constitute the same group. For example, the VTOL rotor 20-1L in the first row 24a and the VTOL rotor 20-4R in the fourth row 24d cancel each other's torque. The VTOL rotor 20-1R in the first row 24a and the VTOL rotor 20-4L in the fourth row 24d cancel each other's torque. The VTOL rotor 20-2L in the second row 24b and the VTOL rotor 20-3R in the third row 24c cancel each other's torque. The VTOL rotor 20-2R in the second row 24b and the VTOL rotor 20-3L in the third row 24c cancel each other's torque. These four pairs of VTOL rotors 20 may constitute four groups.

[0033] [3-4 Other Groupings] Groupings other than the first to third groupings may also be used. For example, in each of the first to third groupings, two or more groups may be further grouped into the same group.

[0034] Note that the multiple VTOL rotors 20 may be grouped together regardless of the separation distance. For example, the multiple VTOL rotors 20 may be grouped according to the positions of the VTOL rotors 20. A VTOL aircraft 10 may include three or more VTOL rotors 20 in the same row. This row includes VTOL rotors 20 that are relatively far from the center of gravity G and VTOL rotors 20 that are relatively far from the center of gravity G. In such a VTOL aircraft 10, three or more VTOL rotors 20 in the same row may be grouped together regardless of the separation distance.

[0035] [4 Stopping Sequence of Multiple VTOL Rotors 20] As described above, the memory unit 48 stores the stopping order of the VTOL rotors 20. The memory unit 48 also stores the rotating VTOL rotors 20 and the stopped VTOL rotors 20. This allows the control unit 46 to determine the next VTOL rotor 20 to be stopped. Several examples of stopping orders are shown below.

[0036] [4-1 Stopping order of each group in the first grouping (1)] In the case of the first grouping shown in FIG. 3, the control unit 46 may stop the rotation of the VTOL rotor 20 in order from the group farthest from the center of gravity G. Note that there may be multiple groups that are the same distance from the center of gravity G. In such a case, the control unit 46 may stop the rotation of the VTOL rotor 20 in order from the group located at the rear among the multiple groups that are the same distance from the center of gravity G. Alternatively, the control unit 46 may stop the rotation of the VTOL rotor 20 in order from the group located at the front among the multiple groups that are the same distance from the center of gravity G. Note that the distance from the center of gravity G to each group may be the distance (separation distance) from the center of gravity G to the VTOL rotor 20 in each group, or may be the distance from the center of gravity G to the center of gravity of each group.

[0037] In this embodiment, the distance from the center of gravity G to group A (the two VTOL rotors 20 in the first row 24a) is the same as the distance from the center of gravity G to group D (the two VTOL rotors 20 in the fourth row 24d). Also, the distance from the center of gravity G to group B (the two VTOL rotors 20 in the second row 24b) is the same as the distance from the center of gravity G to group C (the two VTOL rotors 20 in the third row 24c).

[0038] The control unit 46 may stop the rotation of each of the VTOL rotors 20 in the order of the first row 24a, the fourth row 24d, the second row 24b, and the third row 24c. Alternatively, the control unit 46 may stop the rotation of each of the VTOL rotors 20 in the order of the fourth row 24d, the first row 24a, the third row 24c, and the second row 24b.

[0039] The control unit 46 may stop the rotation of the VTOL rotor 20 by controlling a mechanical rotor fixing mechanism (not shown). The control unit 46 may stop the rotation of the VTOL rotor 20 by controlling the switching element of the inverter device 38 to stop the motor 40. The control of the inverter device 38 performed by the control unit 46 to stop the rotation of the VTOL rotor 20 is referred to as stop control. Furthermore, the control unit 46 may fix the rotation angle of the VTOL rotor 20 to a predetermined angle.

[0040] Each of Figures 5 to 7 is a graph showing the change over time in the rotational speed of the VTOL rotors 20 of each row in the first grouping. For ease of explanation, Figures 5 to 7 show simplified graphs. Figures 5 to 7 show graphs of three stop control patterns. As shown in Figure 5, the control unit 46 may synchronize the timing at which the stop control is started and adjust the order in which the stop control is ended. Alternatively, as shown in Figure 6, the control unit 46 may adjust the order in which the stop control is started and synchronize the timing at which the stop control is ended. Alternatively, as shown in Figure 7, the control unit 46 may adjust both the order in which the stop control is started and the timing at which the stop control is ended.

[0041] [4-2 Stopping order of each group in the first grouping (2)] In the case of the first grouping shown in Fig. 3, the control unit 46 may stop the rotation of the VTOL rotor 20 in order starting from the group closest to the center of gravity G. The other stopping rules are the same as the rule [4-1] above.

[0042] The control unit 46 may stop the rotation of each of the VTOL rotors 20 in the order of the third row 24c, the second row 24b, the fourth row 24d, and the first row 24a. Alternatively, the control unit 46 may stop the rotation of each of the VTOL rotors 20 in the order of the second row 24b, the third row 24c, the first row 24a, and the fourth row 24d.

[0043] [4-3 Stopping order of each group in the first grouping (3)] The control unit 46 may stop the rotation of the VTOL rotors 20 in a predetermined order regardless of the center of gravity G. The eight VTOL rotors 20 may be divided into small groups (first row 24a to fourth row 24d) by a first grouping, and the small groups may be further divided into multiple large groups. In this grouping, the control unit 46 selects small groups from the multiple large groups in order and stops the rotation of the VTOL rotors 20 in the selected small groups in order.

[0044] For example, the four small groups (first row 24a to fourth row 24d) may be divided into two large groups: a front group (first row 24a, second row 24b) and a rear group (third row 24c, fourth row 24d). In this grouping, the control unit 46 may alternately select small groups from the front group and the rear group and stop the rotation of the VTOL rotors 20 in the selected small group in order. As a specific example, the control unit 46 may stop the rotation of each VTOL rotor 20 in the order of the first row 24a, the fourth row 24d, the second row 24b, and the third row 24c. This order is ultimately the same as the stopping order shown in FIG. 5 and the like. Alternatively, the control unit 46 may stop the rotation of each VTOL rotor 20 in the order of the fourth row 24d, the first row 24a, the third row 24c, and the second row 24b. Alternatively, the control unit 46 may stop the rotation of each of the VTOL rotors 20 in the order of the first row 24a, the third row 24c, the second row 24b, and the fourth row 24d. Alternatively, the control unit 46 may stop the rotation of each of the VTOL rotors 20 in the order of the fourth row 24d, the second row 24b, the third row 24c, and the first row 24a.

[0045] [4-4 Stopping order of each group by second grouping (1)] In the case of the second grouping shown in FIG. 4, the control unit 46 may stop the rotation of the VTOL rotors 20 in order from the group farthest from the center of gravity G.

[0046] The control unit 46 may first stop the rotation of each of the VTOL rotors 20 in the first row 24a and the fourth row 24d. Next, the control unit 46 may stop the rotation of each of the VTOL rotors 20 in the second row 24b and the third row 24c.

[0047] Each of Figures 8 to 10 is a graph showing the change over time in the rotational speed of the VTOL rotors 20 of each row in the second grouping. For ease of explanation, Figures 8 to 10 show simplified graphs. Figures 8 to 10 show graphs of three stop control patterns. As shown in Figure 8, the control unit 46 may synchronize the timing at which the stop control is started and adjust the order in which the stop control is ended. Alternatively, as shown in Figure 9, the control unit 46 may adjust the order in which the stop control is started and synchronize the timing at which the stop control is ended. Alternatively, as shown in Figure 10, the control unit 46 may adjust both the order in which the stop control is started and the timing at which the stop control is ended.

[0048] [4-5 Stopping order of each group by second grouping (2)] In the case of the second grouping shown in FIG. 4, the control unit 46 may stop the rotation of the VTOL rotors 20 in order from the group closest to the center of gravity G.

[0049] The control unit 46 may first stop the rotation of each of the VTOL rotors 20 in the second row 24b and the third row 24c. Next, the control unit 46 may stop the rotation of each of the VTOL rotors 20 in the first row 24a and the fourth row 24d.

[0050] [5. Stop processing performed by the control unit 46] FIG. 11 is a flowchart of the stop processing performed by the control unit 46. The control unit 46 starts the processing shown in FIG. 11 after the VTOL aircraft 10 transitions from the takeoff process to the cruising process. For example, when the VTOL aircraft 10 is moving forward at a predetermined speed or higher, the wings (front wings 14 and rear wings 16) generate sufficient lift. For this reason, the control unit 46 may operate the cruise rotor 22 and then stop the rotation of each VTOL rotor 20 in response to the forward speed reaching a predetermined speed or higher. The control unit 46 constantly stores the operating state (rotating or stopped) of each VTOL rotor 20 in the memory unit 48.

[0051] In step S1, the control unit 46 determines whether the attitude of the aircraft is stable. The control unit 46 may determine the degree of stability of the aircraft's attitude based on, for example, each of the pitch, roll, and yaw. The control unit 46 determines that the behavior in the pitch direction is stable when the pitch is within a predetermined pitch range. The control unit 46 determines that the behavior in the roll direction is stable when the roll is within a predetermined roll range. The control unit 46 determines that the behavior in the yaw direction is stable when the yaw is within a predetermined yaw range. Each of the pitch range, roll range, and yaw range is stored in advance in the storage unit 48. The control unit 46 determines that the aircraft's attitude is stable when the behavior of each of the pitch, roll, and yaw directions is stable. On the other hand, the control unit 46 determines that the aircraft's attitude is not stable when at least one of the behaviors of the pitch, roll, and yaw directions is not stable. If the aircraft's attitude is stable (step S1: YES), the process proceeds to step S2. On the other hand, if the attitude of the aircraft is not stable (step S1: NO), the determination in step S1 is repeated.

[0052] In step S2, the control unit 46 selects the group that is first in the stopping order from among the groups that are rotating the VTOL rotors 20. The control unit 46 simultaneously stops the rotation of all of the VTOL rotors 20 included in the selected group. That is, the control unit 46 performs stopping control. The control unit 46 stores the stopped VTOL rotors 20 in the memory unit 48. When the processing of step S2 is completed, the processing proceeds to step S3.

[0053] In step S3, the control unit 46 determines whether or not the rotation of all of the VTOL rotors 20 has been stopped. If the rotation of all of the VTOL rotors 20 has been stopped (step S3: YES), the stop processing shown in Fig. 11 ends. On the other hand, if some of the VTOL rotors 20 are rotating (step S3: NO), the processing proceeds to step S4.

[0054] In step S4, the control unit 46 starts timing. In step S5, the control unit 46 determines whether a predetermined time has elapsed. The predetermined time is pre-stored in the memory unit 48. If the predetermined time has elapsed (step S5: YES), the process proceeds to step S6. On the other hand, if the predetermined time has not elapsed (step S5: NO), the process of step S5 continues. The control unit 46 continues timing until the predetermined time has elapsed. In step S6, the control unit 46 ends timing. Thereafter, the process returns to step S2.

[0055] As described above, in this embodiment, the control unit 46 does not stop the rotation of all of the VTOL rotors 20 simultaneously, but stops the rotation of the VTOL rotors 20 in predetermined groups. This gradually reduces the vertical thrust, minimizing changes in vertical thrust. Therefore, the ride comfort of the VTOL aircraft 10 is not adversely affected.

[0056] [6 Other] When the control unit 46 stops the power supplied to the motor 40, the VTOL rotor 20 may rotate due to an external force (air resistance, wind, etc.). When the VTOL rotor 20 rotates due to the external force, the motor 40 generates electricity. The control unit 46 may rotate the VTOL rotor 20 due to the external force before fixing the rotation angle of the VTOL rotor 20 at a predetermined angle. In this case, the control unit 46 may control the switching elements of the inverter device 38 so that the power storage device 32 is charged with the power generated by the motor 40.

[0057] FIG. 12 is a top view of a vertical take-off and landing aircraft 10' of a type different from the vertical take-off and landing aircraft 10 of FIG. 1. In the VTOL aircraft 10' shown in FIG. 12, eight VTOL rotors 20 are arranged in the longitudinal direction. 2 In such a VTOL aircraft 10', the eight VTOL rotors 20 may be divided into a plurality of groups, and the stopping order of the VTOL rotors 20 may be determined for each group.

[0058] [7 Inventions Obtained from the Embodiments] The invention that can be understood from the above embodiment will be described below.

[0059] An embodiment of the present invention is a vertical take-off and landing aircraft (10, 10') comprising a plurality of VTOL rotors (20) that generate vertical thrust, one or more cruise rotors (22) that generate horizontal thrust, one or more wings (14, 16) that generate lift in conjunction with the horizontal movement of the aircraft, and a controller (46) that controls the operation of each of the plurality of VTOL rotors and one or more cruise rotors, wherein the plurality of VTOL rotors are divided into a plurality of groups, each of the VTOL rotors being included in one of the groups, and the controller sequentially stops the rotation of the plurality of VTOL rotors on a group-by-group basis after lift is generated by the wings.

[0060] In the above configuration, the controller stops the rotation of the VTOL rotors in predetermined groups rather than simultaneously stopping all of the VTOL rotors. This configuration gradually reduces the vertical thrust, minimizing changes in vertical thrust. This prevents the VTOL aircraft from becoming less comfortable.

[0061] In the above aspect, the plurality of groups may be divided according to the distance from the center of gravity (G) of the vertical take-off and landing aircraft to each of the VTOL rotors.

[0062] In the above aspect, each of the groups may be made up of a plurality of the VTOL rotors having the same distance.

[0063] According to the above configuration, it is possible to maintain balance of vertical thrust before and after the rotation of the VTOL rotor stops.

[0064] In the above aspect, each of the groups may further be configured by a plurality of the VTOL rotors that are positioned at the same position in the fore-and-aft direction.

[0065] According to the above configuration, it is possible to maintain a balance of forces in the roll direction before and after the rotation of the VTOL rotor stops.

[0066] In the above aspect, the controller may stop the rotation of the VTOL rotors in order from the group farthest from the center of gravity.

[0067] In the above aspect, the controller may stop the rotation of the VTOL rotors in order starting from the group closest to the center of gravity.

[0068] In the above aspect, when there are multiple groups that have the same distance from the center of gravity, the controller may stop the rotation of the VTOL rotors in order from the group located rearward among the multiple groups that have the same distance from the center of gravity.

[0069] In the above aspect, when there are multiple groups that have the same distance from the center of gravity, the controller may stop the rotation of the VTOL rotors in order from the group located forward among the multiple groups that have the same distance from the center of gravity.

[0070] In the above aspect, the vertical take-off and landing aircraft may include a plurality of motors (40) each connected to one of the VTOL rotors, and the controller may control the motors to stop the rotation of the VTOL rotor and fix the rotation angle of the VTOL rotor at a predetermined angle.

[0071] In the above aspect, the motor may be connected to an electricity storage device (32).

[0072] In the above aspect, the multiple groups may include a first group and a second group, and one of the motors connected to one of the VTOL rotors in the first group and one of the motors connected to one of the VTOL rotors in the second group may each be connected to a common power storage device.

[0073] In the above aspect, the controller may sequentially stop the rotation of the plurality of VTOL rotors in units of the group after detecting that the attitude of the aircraft is stable.

[0074] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present invention. [Explanation of symbols]

[0075] 10...VTOL aircraft (vertical take-off and landing aircraft) 14...Forewing (wing) 16...Rear wing (wing) 20, 20-1L, 20-1R, 20-2L, 20-2R, 20-3L, 20-3R, 20-4L, 20-4R…VTOL rotor 22...cruise rotor 32...electricity storage device 40...Motor 46...Controller

Claims

[Claim 1] a plurality of VTOL rotors that generate vertical thrust; one or more cruise rotors that generate horizontal thrust; one or more wings that generate lift as the aircraft moves in the horizontal direction; a controller for controlling the operation of each of the plurality of VTOL rotors and one or more cruise rotors; A vertical take-off and landing aircraft comprising: The plurality of VTOL rotors are divided into a plurality of groups, and each of the VTOL rotors is included in one of the groups; the plurality of groups are divided according to a distance from a center of gravity of a vertical take-off and landing aircraft to each of the VTOL rotors; Each of the groups is made up of a plurality of the VTOL rotors having the same distance, Each of the VTOL rotors is assigned a stop order; The controller stops the rotation of the multiple VTOL rotors in groups one after another after lift is generated by the wings, and stops the rotation of the VTOL rotors in order, starting with the group closest to the center of gravity.

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