Abstract: The present disclosure relates to the technical field of autonomous underwater vehicles, in particular to an unmanned cable-free operation type autonomous underwater vehicle. The unmanned cable-free operation type autonomous underwater vehicle includes a bow, a middle and a stern, each of the bow, the middle and the stern is of a hollow structure, the middle is provided with a manipulator lifting device and a cabin door opening and closing mechanism, the bow is provided with a first horizontal channel propeller and a first vertical channel propeller, and the stern is provided with two second vertical channel propellers and four main propellers. High-speed cruising of the unmanned cable-free operation type autonomous underwater vehicle can be achieved, and stable and precise hovering needed by the operation of the unmanned cable-free operation type autonomous underwater vehicle can also be achieved.

Abstract: Embodiments provide a method for geomagnetically detecting a submarine cable, including: performing a preliminary detection by controlling an underwater robot equipped with a proton magnetometer; determining a preliminary direction and location of the cable based on preliminary detection information; controlling the underwater robot equipped with the proton magnetometer and two fluxgate magnetometers to launch into the water; controlling the underwater robot to travel over the cable and determining specific location information of the cable; controlling a heading of the underwater robot to move along the preliminary direction of the cable; and controlling the underwater robot equipped with the proton magnetometer and the two fluxgate magnetometers to launch into the water; determining whether a fault in the submarine cable occurs and a location of a fault point, based on Z-axis components of the general geomagnetic field and launching depth data of the underwater robot.

Abstract: An engineering system for collecting and utilizing regional rainwater includes a rainwater collection system, a water quality treatment system, and a control and allocation system. The rainwater collection system includes a rainwater collection ditch for a hardened underlying surface, a barrier and a water storage tank. The water quality treatment system includes a filter system. The control and allocation system includes a water quality monitoring device, a water level monitor, a control gate and a water pump. The filter system is connected to the underlying surface through the rainwater collection ditch, and the filter system is connected to the water storage tank. The control gate is disposed between the filter system and the water storage tank. The water quality monitoring device and the water level monitor are disposed within the water storage tank. The water pump is used to drain water from the water storage tank.

Abstract: A method of forming a porous three-dimensional (3D) is disclosed. The method comprises (I) printing a first composition on a substrate (16) with the nozzle (12) of the apparatus (10) to form at least one first filament (14) comprising the first composition, (II) selectively controlling the distance and/or the speed such that the at least one first filament coils on the substrate to give a first layer on the substrate, the first layer comprising a coiled filament, optionally repeating steps I) and II) with independently selected composition(s) for any additional layer(s), and (III) exposing the layer(s) to a solidification condition. A porous three-dimensional (3D) article formed in accordance with the method is also disclosed.

Abstract: According to a machining principle of the CNC gear hobbing machine, a functional relation between a geometric error of a gear and a tracking error of each motion axis of the machine tool is constructed; a machining error mathematical model of tooth profile deviation, tooth pitch deviation and tooth direction deviation at each position control time point is established by tracking errors of each motion axis; a compensation quantity required for a workpiece rotation axis at the next position control time point is calculated by establishing a decoupling compensation model; average absolute values of machining errors and a total compensation quantity of the machining errors under the conditions of not adopting the synchronous control method and adopting the synchronous control method in the total position control time are obtained by calculating machining error values of each position controls time point, and the synchronized multi-axis motion control is completed.

Abstract: According to a machining principle of the CNC gear hobbing machine, a functional relation between a geometric error of a gear and a tracking error of each motion axis of the machine tool is constructed; a machining error mathematical model of tooth profile deviation, tooth pitch deviation and tooth direction deviation at each position control time point is established by tracking errors of each motion axis; a compensation quantity required for a workpiece rotation axis at the next position control time point is calculated by establishing a decoupling compensation model; average absolute values of machining errors and a total compensation quantity of the machining errors under the conditions of not adopting the synchronous control method and adopting the synchronous control method in the total position control time are obtained by calculating machining error values of each position controls time point, and the synchronized multi-axis motion control is completed.

Abstract: An engineering system for collecting and utilizing regional rainwater includes a rainwater collection system, a water quality treatment system, and a control and allocation system. The rainwater collection system includes a rainwater collection ditch for a hardened underlying surface, a barrier and a water storage tank. The water quality treatment system includes a filter system. The control and allocation system includes a water quality monitoring device, a water level monitor, a control gate and a water pump. The filter system is connected to the underlying surface through the rainwater collection ditch, and the filter system is connected to the water storage tank. The control gate is disposed between the filter system and the water storage tank. The water quality monitoring device and the water level monitor are disposed within the water storage tank. The water pump is used to drain water from the water storage tank.

Abstract: A method of forming a porous three-dimensional (3D) is disclosed. The method comprises (I) printing a first composition on a substrate (16) with the nozzle (12) of the apparatus (10) to form at least one first filament (14) comprising the first composition, (II) selectively controlling the distance and/or the speed such that the at least one first filament coils on the substrate to give a first layer on the substrate, the first layer comprising a coiled filament, optionally repeating steps I) and II) with independently selected composition(s) for any additional layer(s), and (III) exposing the layer(s) to a solidification condition. A porous three-dimensional (3D) article formed in accordance with the method is also disclosed.