Position estimation device and position estimation method

1. A flight vehicle, comprising:

a plurality of rotors;

a Global Positioning System (GPS) receiver configured to receive a GPS signal from a GPS satellite;

a lower side camera on a lower side of the flight vehicle, wherein an optical axis of the lower side camera is toward a vertical direction;

an ultrasonic sensor configured to emit an ultrasonic wave toward the vertical direction and receive a reflected wave of the ultrasonic wave; and

circuitry configured to:

control a flight of the flight vehicle based on the plurality of rotors, wherein

the flight corresponds to at least one of a hovering operation of the flight vehicle, a movement of the flight vehicle, and a turning operation of the flight vehicle, and

the flight is based on flight route information; and

estimate, during the flight in a flight area, a position of the flight vehicle based on at least the received GPS signal, the lower side camera, and the received reflected wave.

2. The flight vehicle according to claim 1 , further comprising an inertial sensor,

wherein the circuitry is further configured to estimate, during the flight, the position and a posture of the flight vehicle based on the inertial sensor.

3. The flight vehicle according to claim 2 , wherein

the circuitry is further configured to obtain a weight of a position estimation system, and

the position estimation system includes at least two of the GPS receiver, the lower side camera, the ultrasonic sensor, and the inertial sensor.

4. The flight vehicle according to claim 3 , wherein the weight of the position estimation system is determined based on a status of the GPS receiver.

5. The flight vehicle according to claim 3 , wherein

the position estimation system includes simultaneous localization and mapping (SLAM) based on the lower side camera, and

the weight of the position estimation system is determined based on feature points of the SLAM.

6. The flight vehicle according to claim 3 , wherein the weight of the position estimation system corresponds to a reliability associated with the position estimation system.

7. The flight vehicle according to claim 2 , wherein

the circuitry is further configured to estimate the position of the flight vehicle based on a time delay parameter,

the time delay parameter indicates a time delay between a position estimation system by the GPS receiver and a position estimation system by the inertial sensor.

8. The flight vehicle according to claim 2 , wherein the inertial sensor includes a gyro sensor and an acceleration sensor.

9. The flight vehicle according to claim 1 , wherein

the flight area includes a first area in which a sufficient GPS signal reaches from the GPS satellite and a second area in which an insufficient GPS signal reaches from the GPS satellite, and

a strength of the sufficient GPS signal is greater than a strength of the insufficient GPS signal.

10. The flight vehicle according to claim 9 , wherein

the first area is in outdoor environment and the second area is in indoor environment, and

the flight vehicle is configured to reciprocate between the outdoor environment and the indoor environment.

11. The flight vehicle according to claim 1 , further comprising a gimbal for the lower side camera.

12. A method, comprising:

in a flight vehicle that includes a plurality of rotors, a Global Positioning System (GPS) receiver, a lower side camera on a lower side of the flight vehicle, an ultrasonic sensor, and circuitry, wherein an optical axis of the lower side camera is toward a vertical direction:

receiving, by the GPS receiver, a GPS signal from a GPS satellite;

emitting, by the ultrasonic sensor, an ultrasonic wave toward the vertical direction and receiving a reflected wave of the ultrasonic wave;

controlling, by the circuitry, based on the plurality of rotors, a flight of the flight vehicle, wherein

the flight corresponds to at least one of a hovering of the flight vehicle, a movement of the flight vehicle, and a turning of the flight vehicle, and

the flight is based on flight route information; and

estimating, by the circuitry, during the flight in a flight area, a position of the flight vehicle based on at least the received GPS signal, the lower side camera, and the received reflected wave.

13. A non-transitory computer-readable medium having stored thereon computer-executable instructions, which when executed by a computer in a flight vehicle, cause the computer to execute operations, the operations comprising:

receiving, by a Global Positioning System (GPS) receiver of the flight vehicle, a GPS signal from a GPS satellite, wherein

the flight vehicle includes a lower side camera on a lower side of the flight vehicle, and

an optical axis of the lower side camera is toward a vertical direction;

emitting, by an ultrasonic sensor of the flight vehicle, an ultrasonic wave toward the vertical direction and receiving a reflected wave of the ultrasonic wave;

controlling, by circuitry of the flight vehicle, a flight of the flight vehicle, wherein

the flight corresponds to at least one of a hovering of the flight vehicle, a movement of the flight vehicle, and a turning of the flight vehicle, and

the flight is based on flight route information; and

estimating, by the circuitry of the flight vehicle, during the flight in a flight area, a position of the flight vehicle based on at least the received GPS signal, the lower side camera, and the received reflected wave.