Abstract: A helical antenna, including a printed circuit board and a radiating body provided above the printed circuit board. The radiating body includes at least one main helical arm and at least one parasitic helical arm. Each main helical arm corresponds to at least one parasitic helical arm. Each main helical arm is arranged in parallel with and is spaced with its corresponding parasitic helical arm. A first terminal of each main helical arm is electrically connected to a first terminal of the corresponding parasitic helical arm. A second terminal of the main helical arm and a second terminal of the parasitic helical arm are both in a floating state, and a length of the parasitic helical arm is greater than a length of its corresponding main helical arm.

Abstract: A helical antenna, including a printed circuit board and a radiating body provided above the printed circuit board. The radiating body includes at least one main helical arm and at least one parasitic helical arm. Each main helical arm corresponds to at least one parasitic helical arm. Each main helical arm is arranged in parallel with and is spaced with its corresponding parasitic helical arm. A first terminal of each main helical arm is electrically connected to a first terminal of the corresponding parasitic helical arm. A second terminal of the main helical arm and a second terminal of the parasitic helical arm are both in a floating state, and a length of the parasitic helical arm is greater than a length of its corresponding main helical arm.

Abstract: A two-degree-of-freedom rotation control device includes a rotary body having a friction spherical surface, wherein a load mounting platform is provided on a top of the rotating body or inside the rotating body; a fixing and supporting structure configured to hold the rotating body, to allow the rotating body to have only a rotational degree of freedom; and a driving motor, wherein, a driving end of the driving motor is in direct contact with the friction spherical surface of the rotating body, to form a friction transmission pair tangent to the friction spherical surface. An application system has the two-degree-of-freedom rotation control device and a working unit on the two-degree-of-freedom rotation control device.

Abstract: A method for guiding a terrestrial vehicle along a desired path can include receiving a position signal from a global navigation satellite system (GNSS) antenna and a gyro signal from a gyro sensor that is indicative of: (i) at least one of a pitch and a roll of the terrestrial vehicle, and (ii) a gyro-based heading direction. A position of a point of interest of the terrestrial vehicle at a location different than the GNSS antenna can be determined based on the position signal, the gyro signal, and a positional relationship between the first location and the second location. A position-based heading direction of the point of interest of the terrestrial vehicle can be determined based on the determined position of the point of interest and at least one previously determined position of the point of interest.

Abstract: A two-degree-of-freedom rotation control device includes a rotary body having a friction spherical surface, wherein a load mounting platform is provided on a top of the rotating body or inside the rotating body; a fixing and supporting structure configured to hold the rotating body, to allow the rotating body to have only a rotational degree of freedom; and a driving motor, wherein, a driving end of the driving motor is in direct contact with the friction spherical surface of the rotating body, to form a friction transmission pair tangent to the friction spherical surface. An application system has the two-degree-of-freedom rotation control device and a working unit on the two-degree-of-freedom rotation control device.

Abstract: A method for guiding a terrestrial vehicle along a desired path can include receiving a position signal from a global navigation satellite system (GNSS) antenna and a gyro signal from a gyro sensor that is indicative of: (i) at least one of a pitch and a roll of the terrestrial vehicle, and (ii) a gyro-based heading direction. A position of a point of interest of the terrestrial vehicle at a location different than the GNSS antenna can be determined based on the position signal, the gyro signal, and a positional relationship between the first location and the second location. A position-based heading direction of the point of interest of the terrestrial vehicle can be determined based on the determined position of the point of interest and at least one previously determined position of the point of interest.