Abstract: A method for accurately positioning a navigation target point includes: selecting a navigation reference with a fixed position, acquiring positions of the navigation reference and the navigation target point in a navigation coordinate system respectively, and calculating a position of the navigation target point relative to the navigation reference, so as to further obtain a position of the navigation target point in a coordinate system of the navigation reference. As long as the navigation reference does not move, the coordinate system of the navigation reference will not change during the entire navigation process, and spatial position coordinates of the navigation target point in the coordinate system of the navigation reference will not be interfered by the navigation coordinate system.

Abstract: A lock pin-type automobile synchronizer includes a higher gear conical ring (1) and a lower gear conical ring (4) which are arranged at the sides of a sliding gear sleeve (3). A higher gear lock pin (2) is fixed to one side of the higher gear conical ring (1). A lower gear lock pin (5, 6) is fixed to one side of the lower gear conical ring (4). A pin hole corresponding to the higher gear (2) lock pin and the lower gear lock pin (5, 6) is arranged on the sliding gear sleeve (3). The number of lower gear lock pins (5, 6) is higher than the number of higher gear lock pins (2).

Abstract: A lock pin-type automobile synchronizer includes a higher gear conical ring (1) and a lower gear conical ring (4) which are arranged at the sides of a sliding gear sleeve (3). A higher gear lock pin (2) is fixed to one side of the higher gear conical ring (1). A lower gear lock pin (5, 6) is fixed to one side of the lower gear conical ring (4). A pin hole corresponding to the higher gear (2) lock pin and the lower gear lock pin (5, 6) is arranged on the sliding gear sleeve (3). The number of lower gear lock pins (5, 6) is higher than the number of higher gear lock pins (2).

Abstract: This invention relates to a main-box-and-auxiliary-box-structural twin-countershaft twelve-speed transmission, with a main box and an auxiliary box mainly. Said main box has an input shaft (1), a main shaft (10) and two countershafts (14) arranged symmetrically at the two sides of the main shaft, there being provided corresponding gear drive between the main shaft and the countershafts, there being provided six gears positioned independently and three synchronizers (4) on the main shaft, shift forks (5) for the synchronizers are connected to a shift lever via shift fork shafts (16) and via an operation mechanism.

Abstract: A multi-speed compound vehicular transmission having an auxiliary section with three countershafts, including: a main section; and an auxiliary section, wherein the main section includes an input shaft, an output shaft, a synchronizer and two countershafts symmetrically arranged on both sides of the output shaft; the auxiliary section includes an auxiliary section main shaft and a synchronizer; wherein a reduction gear is arranged on the main shaft, three countershafts are distributed with equal distance around the main shaft, and an output end of the main shaft of auxiliary section is connected to a flange.