# US 12,181,892 B2 · Aircraft position control system, aircraft, and aircraft position control method

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 12,181,892 B2
- Document ID: US12181892B2
- Status: Granted
- Kind: B2
- Application number: 17/767,159
- Filed: 2020-09-01
- Published: 2022-12-01
- Granted: 2024-12-31
- Earliest claimed: 2019-10-11
- Assignees: Mitsubishi Heavy Industries, Ltd.
- Applicants: Mitsubishi Heavy Industries, Ltd.
- Inventors: Toru Kojima
- Web page: https://patentgrep.com/patent/US12181892B2

## CPC

- G05D 1/101: {specially adapted for aircraft}
- B64C 13/18: using automatic pilot
- B64D 45/08: optical
- B64U 20/87: Mounting of imaging devices, e.g. mounting of gimbals
- B64U 70/30: for capturing UAVs in flight by ground or sea-based arresting gear, e.g. by a cable or a net
- B64U 70/92: Portable platforms
- G05D 1/0684: {on a moving platform, e.g. aircraft carrier}
- G05D 1/46: Control of position or course in three dimensions [3D]
- G08G 5/21: located onboard the aircraft
- G08G 5/54: for approach or landing
- G08G 5/74: for monitoring terrain
- B64C 27/04: Helicopters
- B64C 29/00: Aircraft capable of landing or taking-off vertically, e.g. vertical take-off and landing [VTOL] aircraft (rotorcraft B64C27/00)
- B64F 1/02: for arresting aircraft, e.g. nets or cables
- B64U 2101/30: for imaging, photography or videography
- G05D 2109/20: Aircraft, e.g. drones
- G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- B64C: AEROPLANES; HELICOPTERS
- B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
- B64U: UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
- G08G: TRAFFIC CONTROL SYSTEMS (guiding railway traffic, ensuring the safety of railway traffic B61L; arrangement of road signs or traffic signals E01F9/00; radar or analogous systems, sonar systems, lidar systems specially adapted for traffic control G01S13/91, G01S15/88, G01S17/88; {radar or analogous systems, sonar systems, lidar systems specially adapted for anti-collision purposes G01S13/93, G01S15/93, G01S17/93})
- B64F: GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT; DESIGNING, MANUFACTURING, ASSEMBLING, CLEANING, MAINTAINING OR REPAIRING AIRCRAFT, NOT OTHERWISE PROVIDED FOR; HANDLING, TRANSPORTING, TESTING OR INSPECTING AIRCRAFT COMPONENTS, NOT OTHERWISE PROVIDED FOR

## Abstract

An aircraft position control system includes a processor configured to calculate a feedback manipulated variable of an aircraft by feedback control so that the aircraft heads toward a target landing point, based on at least a relative position and a relative velocity. The processor is further configured to set an addition value, by referring to a switching line preliminarily provided in a manner passing through an origin of a coordinate plane having orthogonal axes representing the relative position and the relative velocity and separating an acceleration region in which the relative velocity is to be increased and a deceleration region in which the relative velocity is to be decreased. The addition value tends to increase the relative velocity when a coordinate point of a current relative position and a current relative velocity is located in the acceleration region to calculate a manipulated variable of the aircraft.

## Claims

### Claim 1

An aircraft position control system comprising:
a processor,
wherein the processor is configured to:
acquire a relative position between an aircraft and a target landing point;
acquire a relative velocity of the aircraft with respect to the target landing point; and
control the aircraft by:
calculating a feedback manipulated variable of the aircraft by feedback control so that the aircraft heads toward the target landing point, based on at least the relative position and the relative velocity;
setting an addition value, by referring to a switching line preliminarily provided in a manner passing through an origin of a coordinate plane having orthogonal axes representing the relative position and the relative velocity and separating an acceleration region in which the relative velocity is increased and a deceleration region in which the relative velocity is decreased, wherein the addition value is set so as to: (i) increase the relative velocity when a coordinate point of a current relative position and a current relative velocity is located in the acceleration region with respect to the switching line; or (ii) decrease the relative velocity when the coordinate point is located in the deceleration region with respect to the switching line; and
calculating a manipulated variable of the aircraft by adding the addition value, which has been set, to the feedback manipulated variable.

### Claim 2 (depends on 1)

The aircraft position control system according to claim 1, wherein the switching line is a straight line extending on the coordinate plane between a quadrant in which a velocity of the aircraft is higher than a velocity of the target landing point and the aircraft is behind the target landing point in a forward direction, and a quadrant in which the velocity of the aircraft is lower than the velocity of the target landing point, and the aircraft is ahead of the target landing point in the forward direction.

### Claim 3 (depends on 1)

The aircraft position control system according to claim 1, wherein the addition value is set in a stepwise manner so that an absolute value thereof becomes: (i) larger for a further distance on the coordinate plane between the coordinate point and the switching line; or (ii) smaller for a closer distance between the coordinate point and the switching line.

### Claim 4 (depends on 1)

The aircraft position control system according to claim 1, wherein the processor is configured to calculate the feedback manipulated variable by Proportional-Integral-Derivative (PID) control, and skip an integration operation of the PID control when the relative velocity is equal to or higher than a predetermined value.

### Claim 5 (depends on 1)

The aircraft position control system according to claim 1, wherein the processor is configured to set a plurality of the addition values in accordance with an altitude of the aircraft or a control mode of the aircraft.

### Claim 6 (depends on 1)

The aircraft position control system according to claim 1, wherein the processor is configured to calculate the relative velocity by adding: (i) a first value acquired by applying, to a differential value of the relative position, a low-pass filter configured to attenuate frequencies equal to or higher than a cutoff frequency; and (ii) a second value acquired by applying, to a velocity of the aircraft, a high-pass filter configured to attenuate frequencies below the cutoff frequency.

### Claim 7 (depends on 1)

The aircraft position control system according to claim 1, wherein the processor is configured to acquire a velocity of the aircraft and a velocity of the target landing point, and calculate the relative velocity based on a difference between the velocity of the aircraft and the velocity of the target landing point.

### Claim 8 (depends on 1)

The aircraft position control system according to claim 1, further comprising an imaging device configured to be mounted on the aircraft, wherein the processor is configured to perform image processing on a captured image of a marker provided at the target landing point taken by the imaging device, and calculate the relative position.

### Claim 9 (depends on 1)

An aircraft comprising the aircraft position control system according to claim 1.

### Claim 10

An aircraft position control method comprising:
acquiring, by a processor, a relative position between an aircraft and a target landing point;
acquiring, by the processor, a relative velocity of the aircraft with respect to the target landing point;
calculating, by the processor, a feedback manipulated variable of the aircraft by feedback control so that the aircraft heads toward the target landing point, based on at least the relative position and the relative velocity;
setting, by the processor, an addition value, by referring to a switching line preliminarily provided in a manner passing through an origin of a coordinate plane having orthogonal axes representing the relative position and the relative velocity and separating an acceleration region in which the relative velocity is increased and a deceleration region in which the relative velocity is decreased, wherein the addition value is set so as to: (i) increase the relative velocity when a coordinate point of a current relative position and a current relative velocity is located in the acceleration region with respect to the switching line; or (ii) decrease the relative velocity when the coordinate point is located in the deceleration region with respect to the switching line;
calculating, by the processor, a manipulated variable of the aircraft by adding the addition value, which has been set, to the feedback manipulated variable; and
controlling, by the processor, the aircraft automatically to head toward the target landing point, based on at least the feedback manipulated variable.