Ornithopter

Patent metadata

Field	Value
Publication number	US-9745058-B2
Application number	US-201414759321-A
Country	US
Kind code	B2
Filing date	Feb 19, 2014
Priority date	Feb 21, 2013
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

An ornithopter includes a main wing mounted on a fuselage, and a control system configured to control a flapping motion of the main wing. The main wing includes an inner spar, an outer spar, and a wrist portion disposed between the inner spar and the outer spar and which varies a bending angle, which is a relative angle between the inner spar and the outer spar, within a predetermined angle range. The control system includes an actuator which performs a raising motion and a lowering motion of the inner spar by moving the inner spar in an upward direction and in a downward direction, an angle sensor which measures the bending angle, and a control unit which controls the actuator to move the inner spar in response to the measured bending angle.

First claim

The invention claimed is:

1. An ornithopter comprising:
a main wing mounted on a fuselage; and
a control system configured to control a flapping motion of the main wing,
wherein the main wing comprises:
an inner spar extending outwardly from the fuselage;
an outer spar extending outwardly from the inner spar; and
a wrist portion disposed between the inner spar and the outer spar, and configured to vary a bending angle within a predetermined angle range, the bending angle being a relative angle between the inner spar and the outer spar,
wherein the control system comprises:
an actuator configured to perform a raising motion of the inner spar by moving the inner spar in an upward direction and to perform a lowering motion of the inner spar by moving the inner spar in a downward direction;
an angle sensor mounted in the wrist portion, and configured to measure the bending angle, which is the relative angle between the inner spar and the outer spar; and
a control unit configured to control the actuator to move the inner spar in response to the measured bending angle of the angle sensor,
wherein the outer spar is arranged to move in a passive manner by following the lowering and raising motion of the inner spar.

2. The ornithopter according to claim 1 , wherein the bending angle in a state in which the outer spar is located at a top position within the predetermined angle range is defined as an upper limit angle,
wherein the control unit is configured to start the lowering motion of the inner spar by controlling the actuator when a state in which the bending angle reaches the upper limit angle is detected after the raising motion of the inner spar.

3. The ornithopter according to claim 1 , wherein the bending angle in a state in which the outer spar is located at a bottom position within the predetermined angle range is defined as an lower limit angle,
wherein the control unit is configured to start the raising motion of the inner spar by controlling the actuator when a state in which the bending angle reaches the lower limit angle is detected after the lowering motion of the inner spar.

4. The ornithopter according to claim 1 , further comprising:
a cushioning member mounted in the wrist portion, and configured to mitigate momentum of relative movement of the outer spar with respect to the inner spar.

5. The ornithopter according to claim 1 , wherein the main wing comprises a main spar including said inner spar and said outer spar,
wherein the main wing further comprises a rib extending rearwardly from the main spar, and
wherein the rib has an S-shaped camber.

6. The ornithopter according to claim 5 , wherein an actuator which directly and mechanically moves the rib is not provided.

7. The ornithopter according to claim 1 , wherein said control unit is configured to control the actuator to move the inner spar when the bending angle measured by the angle sensor equals a set reference value.

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Kuroda Satoshi
• Mori Tomoyuki
• Hattori Kazuya
• Tahara Masato
• TAKAYAMA Oki

Classifications

• B64U10/40

  Ornithopters · CPC title

• A63H27/008

  Propelled by flapping of wings (driving mechanisms with extensible rubber bands for toys in general A63H29/18) · CPC title

• B64C33/02 Primary

  Wings; Actuating mechanisms therefor · CPC title

• B64C2201/025

  Operations & Transport · mapped topic