Unmanned aerial vehicle and delivery system

1. An unmanned aerial vehicle that delivers a package, the unmanned aerial vehicle comprising:

a plurality of rotary wings;

a plurality of first motors that rotate the plurality of rotary wings, respectively;

a main body that supports the plurality of first motors;

a connector that is to be connected to a rail, with the main body hanging from the connector, the rail being provided at a position spaced apart from a ground surface;

a movable block that sets an inclination of an imaginary plane containing the plurality of rotary wings relative to a support direction in which the connector is supported on the rail; and

a control circuit that controls the plurality of first motors and the movable block, wherein

the connector includes:

a first end connected to the main body; and

a second end to be slidably connected to the rail,

the support direction extends from the first end toward the second end of the connector, and

when the second end of the connector is connected to the rail, the control circuit:

(i) sets a rotation rate of the plurality of first motors to a rotation rate that is lower than a minimum rotation rate necessary for causing the unmanned aerial vehicle to float and that is higher than a minimum rotation rate necessary for propelling the unmanned aerial vehicle in a direction in which the rail extends; and

(ii) causes the movable block to increase an angle formed by a normal direction of the imaginary plane relative to the support direction of the connector.

2. The unmanned aerial vehicle according to claim 1 , further comprising:

a pair of wings.

3. The unmanned aerial vehicle according to claim 1 , wherein

the control circuit disengages the connector from the rail when a propulsion speed of the unmanned aerial vehicle exceeds a predetermined value after the movable block has increased the angle.

4. The unmanned aerial vehicle according to claim 3 , wherein

when the connector is disengaged from the rail, the control circuit:

causes the movable block to reduce the angle; and

controls the rotation rate of the plurality of first motors to a rotation rate higher than the minimum rotation rate necessary for causing the unmanned aerial vehicle to float.

5. The unmanned aerial vehicle according to claim 1 , wherein

the connector includes:

a support portion swingably connected to the main body; and

a first arm connected to one end of the support portion.

6. The unmanned aerial vehicle according to claim 5 , wherein

the connector further includes a second arm connected to the one end of the support portion.

7. The unmanned aerial vehicle according to claim 6 , wherein

the first arm is a first hanger for hanging the unmanned aerial vehicle from the rail,

the second arm is a second hanger for hanging the unmanned aerial vehicle from the rail, and

the connector further includes:

a first actuator that sets an angle of the first arm relative to the support portion; and

a second actuator that sets an angle of the second arm relative to the support portion.

8. The unmanned aerial vehicle according to claim 7 , wherein

the first arm includes a first hook that extends from a first connected end connected to the first actuator to a first open end,

the second arm includes a second hook that extends from a second connected end connected to the second actuator to a second open end,

the first hook includes a first bent portion that is bent in a first direction and located between the first connected end and the first open end, and

the second hook includes a second bent portion that is bent in a second direction opposite the first direction and located between the second connected end and the second open end.

9. The unmanned aerial vehicle according to claim 8 , wherein

when the unmanned aerial vehicle is slidably hung from a first rail via the first hook and the second hook, the control circuit:

disengages the second hook from the first rail and hooks the second hook onto a second rail by controlling the second actuator, the second rail extending along and adjacent to the first rail; and

disengages the first hook from the first rail and hooks the first hook onto the second mil by controlling the first actuator.

10. The unmanned aerial vehicle according to claim 1 , further comprising:

a hanging wire connected to the main body and provided to hang the package; and

a lift motor that is capable of taking up the hanging wire, wherein

the control circuit:

positions the unmanned aerial vehicle vertically above a storage device for storing the package, with the connector being connected to the rail; and

lets out the hanging wire by actuating the lift motor, lowers the package from the main body, and stores the package into the storage device.

11. The unmanned aerial vehicle according to claim 10 , further comprising:

a thruster device removably attached to the package, wherein

the thruster device includes:

a plurality of propellers;

a plurality of second motors that rotate the plurality of propellers, respectively; and

a support member that supports the plurality of second motors.

12. The unmanned aerial vehicle according to claim 11 , wherein

the plurality of propellers include:

a first propeller disposed on a first side portion of the support member; and

a second propeller disposed on a second side portion of the support member, the second side portion being different from the first side portion.

13. The unmanned aerial vehicle according to claim 12 , wherein

the control circuit causes the thruster device to actuate at least one of the plurality of second motors in at least a portion of a period in which the hanging wire is let out.

14. A delivery system, comprising:

the unmanned aerial vehicle according to claim 1 ;

a plurality of support pillars; and

the rail stretched between two adjacent support pillars of the plurality of support pillars.

15. The delivery system according to claim 14 , wherein

the plurality of support pillars are each a utility pole or a streetlight.