Abstract: An automobile hub fixture includes a fixture body and a positioning apparatus. The fixture body includes a fixed platform and a plurality of clamping claws arranged at intervals in a circumferential direction of the fixed platform. The clamping claws are configured to clamp an outer rim of a hub. The plurality of clamping claws are connected to a driving member by using a linkage, and the driving member drives the clamping claws to radially move along the fixed platform. The positioning apparatus includes a movable platform slidably connected to the clamping claws. A positioning module configured to position an inner rim or the outer rim of the hub is mounted to the movable platform. The machining device includes a fixture, a machine tool, and a minimal quantity lubrication apparatus. The production line includes a machining device, a loading system, a loading and unloading manipulator, and a catching table.

Abstract: A high-efficiency particle analysis method includes the following steps: taking representative air-dried samples and measuring a moisture content; boiling, sieving, weighing and adding a dispersant; conducting a particle analysis test; reading four readings of 1st to 59th and 60th to 90th samples; and drawing a particle size distribution curve showing the relationship between the particle size and the percentage of below a certain diameter. According to the method, a time difference is used to change the measurement mode, and the four readings of the 59th and 90th samples are read in a cycling manner; and a novel test method is provided on the premise of ensuring quality, thus greatly improving the efficiency of a particle analysis test and meeting production requirements.

Abstract: The embodiments of the present application provide an indoor positioning system, including an information source module, a gateway, a first leaky cable and a first positioning device; where the information source module is connected to a first end of the first leaky cable through a feeder; the first positioning device is arranged between the first end of the first leaky cable and the feeder, and the first positioning device is configured to transmit a positioning signal through the first leaky cable, so as to enable the terminal to perform positioning according to the positioning signal. There is no need to set up a new positioning system, thus reducing costs for network construction as well as space requirements for the network construction.