초록 ▼

An ornithopter with two set of opposed wings maintains powered flight by flapping each set of wings. To dampen vibration, each set of wings move 180 degrees out of phase. To further dampen vibration, the empennage and cockpit are articulated to move vertically in response to the movement of the wing

An ornithopter with two set of opposed wings maintains powered flight by flapping each set of wings. To dampen vibration, each set of wings move 180 degrees out of phase. To further dampen vibration, the empennage and cockpit are articulated to move vertically in response to the movement of the wings. Changes of flight direction result from wing warping and changing the center of gravity of the ornithopter.

대표청구항 ▼

An ornithopter with two set of opposed wings maintains powered flight by flapping each set of wings. To dampen vibration, each set of wings move 180 degrees out of phase. To further dampen vibration, the empennage and cockpit are articulated to move vertically in response to the movement of the wing

An ornithopter with two set of opposed wings maintains powered flight by flapping each set of wings. To dampen vibration, each set of wings move 180 degrees out of phase. To further dampen vibration, the empennage and cockpit are articulated to move vertically in response to the movement of the wings. Changes of flight direction result from wing warping and changing the center of gravity of the ornithopter. nitude such that said magnetic attraction force exceeds the weight of the pre-wound bobbin yet allows the bobbin to be rotated on the post by pulling the thread tangentially away from the bobbin; wherein the bobbin comprises a single-flange bobbin. 8. The pre-wound bobbin of claim 7, wherein the magnetized material of the flange adheres flat against a bare, planar steel surface with a magnetic force of about 0.2 to 0.4 pounds per square inch of the magnetic material. 9. The pre-wound bobbin of claim 8, wherein the flange has a surface area of about 0.2 to 0.5 square inch. 10. The pre-wound bobbin of claim 7, wherein the thread has a coating of an adhesive substance such that the thread adheres to itself. 11. A pre-wound bobbin for removably mounting in a steel bobbin case formed as a generally cup-shaped housing having an end wall at one end thereof and being open at the other end thereof and having a post mounted on the end wall, the pre-wound bobbin comprising: a hollow cylindrical non-magnetized core for fitting over the post of the bobbin case such that the core rotates freely relative to the post; a continuous length of thread wound onto the core; and a magnetized flange attached to one end of the core and extending radially outwardly therefrom, the flange exerting a magnetic attraction force on the end wall of the bobbin case when the bobbin is mounted therein with the flange in contact with the end wall such that the flange provides a magnetic drag force resisting rotation of the bobbin. 12. The pre-wound bobbin of claim 11, wherein the flange comprises a flexible sheet magnet. 13. The pre-wound bobbin of claim 11, wherein the flange adheres against a bare, planar steel surface with a magnetic force of about 10 to 20 times the weight of the bobbin. 14. The pre-wound bobbin of claim 11, wherein the core is non-metallic. 15. The pre-wound bobbin of claim 11, wherein the bobbin comprises a single-flange bobbin. 16. The pre-wound bobbin of claim 11, wherein the flange is formed of a magnetized material that adheres flat against a bare, planar steel surface with a magnetic force of about 0.2 to 0.4 pounds per square inch of the magnetized material. 17. The pre-wound bobbin of claim 11, wherein the flange has a circular outer periphery defining an outer diameter of the flange, and the thread is wound to form a substantially cylindrical roll having an initial outer diameter prior to usage of any of the thread, and wherein the outer diameter of the flange does not exceed the initial outer diameter of the roll of thread. 18. The pre-wound bobbin of claim 17, wherein the outer diameter of the flange is less than the initial diameter of the roll of thread. 19. The pre-wound bobbin of claim 11, further comprising a second non-magnetized flange attached to an opposite end of the core from the end having the magnetized flange. 20. The pre-wound bobbin of claim 19, wherein the magnetized and non-magnetized flanges are visually distinct from each other such that it is readily determinable in which direction the bobbin should be loaded into the bobbin case. 21. The pre-wound bobbin of claim 20, wherein both flanges are relatively flexible and the core is relatively rigid. 22. A single-flange pre-wound bobbin for removably mounting in a steel bobbin case formed as a generally cup-shaped housing having an end wall at one end thereof and being open at the other end thereof and having a post mounted on the end wall, the pre-wound bobbin comprising: a hollow cylindrical non-magnetized core for fitting over the post of the bobbin case such that the core rotates freely relative to the post; a continuous length of thread wound onto the core; and a flange formed from a flexible sheet magnet attached to one end of the core and extending radially outwardly therefrom, the flange exerting a magnetic attraction force on the end wall of the bobbin case when the bobbin is mounted therein with the flange in contact with the end wall such