Abstract: A piston limiting structure, including: a cylinder, a piston, and a flange provided with a limiting piece, the cylinder has a piston hole perpendicular to an axial direction of the cylinder and penetrating through the cylinder, and a projection of the piston hole in a penetrating direction is circular. The piston is disposed in the piston hole in a form-fit manner and is slid in the piston hole in a reciprocating manner. A side wall of the piston is provided with a thrust groove, a bottom surface of the thrust groove forms a thrust surface on the side wall of the piston, and the thrust groove does not penetrate through two ends of the side wall of the piston along an axial length of the piston. The limiting piece abuts against the thrust surface.

Abstract: A device and a method of anti-unmanned aerial vehicle based on multi-camera tracking and positioning, including: a bracket, defined a center, a circumference surrounding the center and a central axis passing through the center; at least three cameras, the cameras are evenly distributed and inclined outwardly on the circumference of the bracket, and center lines of view of the cameras forms an inverted cone; a directional antenna, configured to be arranged on the central axis of the bracket; an electromagnetic module, configured to be coupled to the directional antenna; a pan-tilt, connected to the center of the bracket and configured to drive the bracket to rotate; and a control unit, configured to control the pan-tilt to track a target and lock on to the target according to the video image provided by the cameras, such that the electromagnetic module is manipulated to attack the target.

Abstract: A device and a method of anti-unmanned aerial vehicle based on multi-camera tracking and positioning, including: a bracket, defined a center, a circumference surrounding the center and a central axis passing through the center; at least three cameras, the cameras are evenly distributed and inclined outwardly on the circumference of the bracket, and center lines of view of the cameras forms an inverted cone; a directional antenna, configured to be arranged on the central axis of the bracket; an electromagnetic module, configured to be coupled to the directional antenna; a pan-tilt, connected to the center of the bracket and configured to drive the bracket to rotate; and a control unit, configured to control the pan-tilt to track a target and lock on to the target according to the video image provided by the cameras, such that the electromagnetic module is manipulated to attack the target.

Abstract: An antenna structure includes a board unit and a coil unit. The board unit includes a metal board and an insulating board connected with or adjacent to the metal board, and the coil unit is disposed beside the same side of the metal board and the insulating board. In one embodiment, when one narrow side of the metal board and one narrow side of the insulating board connects with each other, the coil unit is disposed right under the commissure of the metal board and the insulating board. In addition, more than half or half of the area of the coil unit is covered by the insulating board, and less than half or half of the area of the coil unit is covered by the metal board. The current direction on the metal board and the current direction on the coil unit are the same as clockwise or counterclockwise.

Abstract: An antenna structure includes a board unit and a coil unit. The board unit includes a metal board and an insulating board connected with or adjacent to the metal board, and the coil unit is disposed beside the same side of the metal board and the insulating board. In one embodiment, when one narrow side of the metal board and one narrow side of the insulating board connects with each other, the coil unit is disposed right under the commissure of the metal board and the insulating board. In addition, more than half or half of the area of the coil unit is covered by the insulating board, and less than half or half of the area of the coil unit is covered by the metal board. The current direction on the metal board and the current direction on the coil unit are the same as clockwise or counterclockwise.