Preparation method of composite electromagnetic wave-absorbing material

The invention discloses a preparation method of a composite electromagnetic wave-absorbing material, and belongs to the technical field of nano materials. The method comprises the following steps: dispersing SiBON powder into a solvent, adding reduced graphene oxide, and uniformly mixing to obtain A; dispersing a silane coupling agent into a solvent, adding acid and controlling the pH value to be 1-3, and carrying out hydrolysis reaction to obtain B; mixing A and B, reacting until layering, and collecting solid substances to obtain SiBON-rGO. According to the invention, the complex dielectric constant and impedance matching of the composite material are successfully adjusted by using SiBON ceramic, a rich interface is introduced to greatly improve the polarization loss of the composite material, and the SiBON content can adjust the balance between the conduction loss and the polarization loss. A composite structure with the SiBON ceramic outer layer and the reduced graphene oxide inner ...

High-maneuverability aircraft fixed time sliding mode accurate guiding method

The invention relates to a high-maneuverability aircraft fixed time sliding mode accurate guiding method. The method comprises the following steps: 1, giving an expected sight angle value, wherein the expected sight angle value is given; giving an initial position and an initial track angle of the aircraft; giving an initial position, an initial track angle and an acceleration of the target; 2, fixed time sliding mode reaching law calculation: calculating a sliding mode surface s1, and calculating a reaching law value required for eliminating an error between an expected line-of-sight angle and an actual line-of-sight angle; 3, estimating the acceleration by using a fixed time observer; and 4, calculating by using a fixed time sliding mode control law: calculating the control quantity u required for enabling the line-of-sight angular rate to approach to zero, wherein the fixed time observer is used for estimating the acceleration component of the target in the line-of-sight coordinate system ...

Unmanned aerial vehicle trajectory tracking method based on reinforcement learning and event triggering

The invention discloses an unmanned aerial vehicle trajectory tracking method based on reinforcement learning and event triggering, and belongs to the technical field of unmanned aerial vehicle automatic control. Establishing a six-degree-of-freedom model of the unmanned aerial vehicle, giving an expected tracking trajectory, and obtaining an expected position, an attitude angle, a speed and an angular speed according to the given trajectory; trajectory tracking error calculation: calculating an error between an actual trajectory and an expected trajectory, defining a filtering tracking error, and deriving the filtering tracking error; performing event triggering mechanism design on the input, designing a state quantity, and designing a reasonable event triggering parameter; an evaluator neural network is designed, and the tracking performance of an evaluation system is designed and used for improving the tracking performance; designing an actuator neural network, and approaching uncertain ...

Flight bus data automatic reading algorithm

The invention belongs to the technical field of test flight data analysis, and particularly relates to a flight bus data automatic reading algorithm. Comprising the following steps: step 1, acquiring bus data, and defining a recording format of each piece of bus data; step 2, loading all bus data into the same working space; step 3, bus data recorded with a predetermined flight mode is searched, one or more time combinations corresponding to the predetermined flight mode are obtained, and each time combination comprises the time for entering the predetermined flight mode and the time for exiting the predetermined flight mode; 4, searching the bus data recorded with the maneuvering numbers, obtaining all the maneuvering numbers in each time combination and the starting time and the ending time corresponding to each maneuvering number, and recording all the maneuvering numbers and the starting time and the ending time corresponding to each maneuvering number into a txt file in a column form ...

Fixed-wing aircraft glide control gain index optimization method based on direct lift force

The invention belongs to the technical field of glide control, and relates to a fixed-wing aircraft glide control gain index optimization method based on direct lift force. According to the control gain optimization method, firstly, the multi-control-surface coordination problem in traditional glide control is considered, the glide control method based on the direct lift force is determined to be adopted, on this basis, the direct lift force control gain is optimized, and compared with a traditional preset gain glide controller, the control gain optimization method has the advantages that when glide control is carried out, the control gain is optimized; the gliding control quality is improved; compared with the basic gain of a traditional control method, after the index-based glide control gain optimization method is optimized, the characteristics of smaller overshoot, higher response speed and rapid convergence are achieved, the situation that the glide quality is poor due to the fact ...

Computer controlled crystal thyratron rectifying arc welding power supply

A computer controlled crystal thyratron rectification arc welding power supply has a rectification unit using thyristor circuit with balance reactor and a control unit composed of synchronous signal generator, sampling amplifier, A/D converter, conduction angle controller and computer. The digital values corresponding to welding current and voltage are compared with presettings in computer and the control angle of main crystal thyratron in feeding circuit is determined based on an algorithm and then converted into synchronous trigger pulse to trigger relative crystal thyratron, so controlling welding current and voltage.

Computer-controlled transistor commutating arc welding power source

Wear-resistant and corrosion-resistant medium-entropy alloy composite protective coating as well as preparation method and application thereof

The invention provides a wear-resistant and corrosion-resistant medium-entropy alloy composite protective coating as well as a preparation method and application thereof, and relates to the technical field of surface engineering. The preparation method of the wear-resistant and corrosion-resistant medium-entropy alloy composite protective coating comprises the following steps that the surface of a metal base material is sequentially electroplated with a metal nickel layer and a graphene oxide modified medium-entropy alloy layer, and the composite coating is obtained; and the composite coating is subjected to heat treatment, and the wear-resistant and corrosion-resistant medium-entropy alloy composite protective coating is obtained. The wear-resistant and corrosion-resistant medium-entropy alloy composite protective coating prepared by the preparation method disclosed by the invention has high binding force with a metal base material, and has good corrosion resistance, wear resistance and ...