Explosion-proof packaging method for unmanned aerial vehicle hardware

Abstract

The invention relates to the technical field of unmanned aerial vehicle safety protection and anti-explosion packaging, and discloses an anti-explosion packaging method for unmanned aerial vehicle hardware, which comprises the following steps: step 1, performing anti-explosion pretreatment on the unmanned aerial vehicle hardware; the inner buffer layer is made of modified silicone rubber, the thickness is accurately calculated through a formula, impact stress can be attenuated by 80% or above, meanwhile, honeycomb-shaped heat dissipation channels are formed, and the problem of heat concentration is solved; the middle anti-explosion barrier layer is made of an aluminum oxide ceramic-silicon carbide fiber composite material, the impact strength is 15-20 MPa, the bending strength is 300-400 MPa, the middle anti-explosion barrier layer can resist explosive shock waves of 1.5 MPa or below, the toughness is further improved through a built-in stainless steel mesh reinforcing layer, and brittle fracture is avoided; the outer protection layer adopts a polyether-ether-ketone (PEEK) + zirconium oxide nano coating (HV1200-1500), is wear-resistant, corrosion-resistant and impact-resistant, flame and fragment leakage can be completely blocked through the cooperation of the three layers, the external temperature in a fault scene is smaller than or equal to 45 DEG C, and the safety protection level is improved by more than three times compared with a traditional package.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of unmanned aerial vehicle safety protection and explosion-proof packaging, and particularly relates to an explosion-proof packaging method for unmanned aerial vehicle hardware. BACKGROUND

[0002] The traditional unmanned aerial vehicle hardware packaging method has four core pain points in high-risk scenarios, which seriously restricts the safe application of the unmanned aerial vehicle.

[0003] The explosion-proof performance is insufficient, and the safety risk is high: the traditional packaging adopts a single plastic shell or a simple buffer structure, which cannot resist the explosion shock wave and high temperature generated by hardware failure (such as battery short circuit and circuit overheating), and is easy to cause flame and fragment leakage, and to cause combustion and explosion of surrounding flammable and explosive substances. The accident rate in oil and gas fields, chemical industry parks and other scenarios is more than 15%.

[0004] The design lacks pertinence, and the adaptability is poor: the structure is not customized in combination with the heat distribution and stress weak points of the unmanned aerial vehicle hardware, heat concentration areas (such as batteries and motor controllers) are blocked after packaging, the temperature is easy to exceed 80 DEG C, and the hardware aging is accelerated; at the same time, the stress weak points (such as interfaces and welding points) are not strengthened, and are easy to crack under vibration and impact, resulting in packaging failure.

[0005] Material and process defects, low reliability: the buffer layer is mostly made of ordinary rubber, and the impact resistance and flame resistance are poor; the explosion-proof barrier layer lacks the support of high-strength composite materials, and the anti-explosion pressure is less than or equal to 0.5 MPa; the welding sealing process is simple, and the air tightness leakage rate is greater than or equal to 1x10⁻ 6 Pa·m³ / s, which cannot meet the strict requirements of high-risk scenarios.

[0006] The detection standard is missing, and the verification is not comprehensive: only simple appearance and power-on tests are performed, extreme failure scenarios such as short circuit and overheating are not simulated, and the packaging stability under vibration and impact is not verified, so that the hardware after packaging is easy to appear "hidden failure" in actual operation, and the safety hidden danger is not completely eliminated. SUMMARY

[0007] The application aims to provide an explosion-proof packaging method for unmanned aerial vehicle hardware to solve the problems in the background.

[0008] To achieve the above-mentioned purpose, the application provides the following technical scheme: an explosion-proof packaging method for unmanned aerial vehicle hardware, comprising the following steps:

[0009] Step one, first, the unmanned aerial vehicle hardware is subjected to explosion-proof pretreatment, the pretreatment process needs to obtain the outer contour data of the unmanned aerial vehicle hardware through a three-dimensional scanning device, generate a three-dimensional model with a precision of 0.01 mm, and then analyze the heat concentration areas and stress weak points on the surface of the hardware based on the three-dimensional model;

[0010] The determination of the heat concentration area needs to be based on the temperature field simulation results of the hardware in full load running state. The hardware is simulated by using finite element analysis software. The environmental temperature is set to -40℃~60℃, the running power is 110% of the rated power of the hardware, the simulation time lasts for 2h, and the area with a temperature higher than 65℃ is extracted as the heat concentration area;

[0011] The determination of the stress weak point is by applying 1.2 times the rated vibration load and 1.5 times the rated impact load to the hardware, and the area with a stress value exceeding 80% of the yield strength of the hardware material is extracted as the stress weak point;

[0012] Step two, then according to the heat concentration area and the stress weak point obtained by pretreatment, a blast-proof packaging structure is customized, which includes an inner buffer layer, a middle blast-proof barrier layer and an outer protective layer;

[0013] The inner buffer layer is made of modified silicone rubber material, with a Shore A hardness of 35±5, and the thickness is determined according to the stress value of the stress weak point, and the specific calculation formula is

[0014]

[0015] Wherein is the thickness of the inner buffer layer, is the maximum stress value of the stress weak point, is the stress area of the stress weak point, is the elastic modulus of the modified silicone rubber, is the stress attenuation amount that the buffer layer can withstand;

[0016] The middle blast-proof barrier layer is made of ceramic matrix composite material, which is woven by alumina ceramic particles and silicon carbide fibers. The particle size of the alumina ceramic particles is 50~100μm, the volume fraction is 65%~75%, the diameter of the silicon carbide fibers is 10~20μm, and the volume fraction is 25%~35%. The thickness of the middle blast-proof barrier layer is determined according to the possible explosion shock wave pressure of the hardware, and the calculation formula is

[0017]

[0018] Wherein is the thickness of the middle blast-proof barrier layer, is the estimated explosion shock wave pressure, is the shock wave action time, is the density of the ceramic matrix composite material, is the propagation speed of the shock wave in the material;

[0019] The outer protective layer is made of polyether ether ketone material, the thickness is set to 3-5mm, and the surface of the outer protective layer needs to be treated with nano ceramic coating, the coating material is zirconium oxide, the coating thickness is 5-10um, prepared by plasma spraying technology, the spraying power is 40-60kW, the spraying distance is 100-150mm;

[0020] Step three, embed the unmanned aerial vehicle hardware into the customized explosion-proof packaging structure, and seal the splicing part of the packaging structure by laser welding technology, the power of laser welding is set to 1500-2000w, the welding speed is 5-10mm / s, the spot diameter is 0.5-1mm, after welding, the packaging structure is detected for air tightness, the detection pressure is 0.3-0.5MPa, the pressure holding time is 30min, to ensure that the air tightness leakage rate is less than 1x10 -9 Pa·m³ / s, at the same time, the explosion-proof performance test is carried out, the fault scene such as short circuit and overheating of hardware is simulated, it is verified that the packaging structure has no flame and fragment leakage in fault state, and the external temperature does not exceed 45℃.

[0021] Preferably, when the unmanned aerial vehicle hardware is pre-processed for explosion-proof, the three-dimensional scanning equipment adopts laser triangulation scanning technology, the scanning speed is set to 5000-8000 points / s, and the scanning resolution is 0.005mm. In the scanning process, the hardware needs to be scanned 360°, and a group of data is collected every 10°, a total of 36 groups of data. The 36 groups of data are fused to generate a complete three-dimensional model by point cloud stitching algorithm. The point cloud stitching algorithm adopts iterative closest point (ICP) algorithm, the iteration number is set to 50-100 times, and the convergence threshold is set to 0.001mm, so as to ensure the accuracy of the three-dimensional model;

[0022] In the temperature field simulation process, the core components of the hardware need to be modeled separately, and the thermal physical parameters such as thermal conductivity and specific heat capacity of each core component are set. The thermal conductivity of the battery is set to 0.8-1.2w / (m·k), and the specific heat capacity is set to 1200-1500j / (kg·k). The thermal conductivity of the motor controller is set to 150-200w / (m·k), and the specific heat capacity is set to 450-500j / (kg·k). The thermal conductivity of the central processing unit is set to 100-120w / (m·k), and the specific heat capacity is set to 380-420j / (kg·k). At the same time, the heat dissipation path is added in the simulation model to simulate the air flow heat dissipation in the actual flight of the unmanned aerial vehicle. The air flow speed is set to 2-8m / s;

[0023] During the stress analysis, a dynamic stress analysis method is adopted, in which vibration and impact loads are applied to the hardware model in a time sequence with a time step of 0.1ms. The stress distribution of the hardware at different time nodes is calculated through the transient dynamic analysis module, the maximum stress value at each time node is extracted, and the location and maximum stress value of the stress weak point are finally determined. Before the stress analysis, the hardware model needs to be meshed, and the mesh element size is set to 0.5~2mm.

[0024] Preferably, the modified silicone rubber material used in the inner buffer layer is prepared by adding 20%~30% (mass fraction) of nano-calcium carbonate particles and 5%~10% (mass fraction) of flame retardant to the base silicone rubber. The nano-calcium carbonate particles have a particle size of 20~50nm and are surface treated with a silane coupling agent at a temperature of 80~100℃ for 2~3h.

[0025] The preparation process of modified silicone rubber specifically includes the following steps:

[0026] The base silicone rubber, nano calcium carbonate particles, and flame retardant are mixed in proportion and added to an internal mixer. The mixture is then mixed for 30 to 60 minutes at a temperature of 120 to 150°C and a speed of 50 to 80 r / min to obtain the mixed rubber compound.

[0027] The mixed rubber compound is transferred to a vulcanizing machine and vulcanized for 10-20 minutes at a temperature of 160-180℃ and a pressure of 10-15MPa to produce an inner buffer layer preform.

[0028] Finally, based on the dimensions of the hardware 3D model, the prefabricated parts are cut using CNC cutting equipment with a cutting accuracy controlled within ±0.05mm. Micro heat dissipation channels are opened on the surface of the inner buffer layer that contacts the hardware. The diameter of the heat dissipation channels is 0.5~1mm, the spacing is 5~10mm, and they are distributed in a honeycomb pattern.

[0029] Preferably, the middle explosion-proof barrier layer is made of a ceramic matrix composite material, and its preparation process specifically includes the following steps:

[0030] First, silicon carbide fiber cloth is prepared by weaving silicon carbide fibers into cloth in the warp and weft directions with a weaving density of 20-30 fibers / cm and a fabric thickness of 0.2-0.3mm. Then, the silicon carbide fiber cloth is coated with boron nitride as the coating material with a coating thickness of 1-2μm. The coating is prepared by chemical vapor deposition (CVD) technology with a deposition temperature of 800-1000℃, a deposition pressure of 5-10kPa, and a deposition time of 2-3h.

[0031] Next, an alumina ceramic slurry is prepared by mixing alumina ceramic particles, sintering aid, and binder in a mass ratio of 90:5:5, adding an appropriate amount of deionized water, and ball milling in a ball mill at a speed of 200~300 r / min for 4~6 hours to prepare a ceramic slurry with a solid content of 60%~70%.

[0032] Then, the ceramic slurry is coated onto silicon carbide fiber cloth using an impregnation-winding process, with a coating thickness of 0.1~0.2 mm / layer. After each layer is coated, it is dried at a temperature of 80~100℃ for 1~2 hours. The coating is repeated for 5~8 layers to obtain the composite material preform.

[0033] Finally, the composite material preform is placed in a sintering furnace and heated to 1600-1800℃ at a heating rate of 5-10℃ / min under inert gas (argon) protection, and held for 3-5 hours for sintering. After sintering, it is cooled to room temperature with the furnace to obtain the middle explosion-proof barrier layer. The impact strength of the middle explosion-proof barrier layer needs to reach 15-20MPa, and the flexural strength needs to reach 300-400MPa. The test is carried out by a universal testing machine with a test speed set at 2-5mm / min. A metal mesh reinforcement layer is set inside the middle explosion-proof barrier layer. The metal mesh is made of stainless steel with a mesh size of 1-2mm and a thickness of 0.1-0.2mm. The metal mesh and the ceramic matrix composite material are combined by hot pressing. The hot pressing temperature is 1200-1400℃, the hot pressing pressure is 20-30MPa, and the hot pressing time is 1-2 hours.

[0034] Preferably, the outer protective layer is made of polyetheretherketone (PEEK) material, which needs to be dried before processing. The drying temperature is 120~150℃ and the drying time is 4~6 hours to remove moisture from the material and prevent air bubbles from forming during processing. The outer protective layer is prepared by injection molding, and the preparation process specifically includes the following steps:

[0035] First, set the injection molding machine's barrel temperature to 340~380℃ (front section temperature 340~350℃, middle section temperature 350~360℃, rear section temperature 360~380℃), mold temperature to 120~150℃, injection pressure to 80~120MPa, injection speed to 50~100mm / s, holding pressure to 60~80MPa, holding time to 5~10s, and cooling time to 20~30s.

[0036] The outer protective layer after molding needs to undergo stress relief treatment. The treatment temperature is 160~180℃, the treatment time is 2~3h, and the cooling rate is 5~10℃ / h, in order to eliminate the internal stress generated during the injection molding process.

[0037] The nano-ceramic coating on the surface of the outer protective layer is prepared using atmospheric plasma spraying technology. Before spraying, the PEEK surface needs to be sandblasted. The sandblasting medium is alumina sand with a particle size of 80~120 mesh, the sandblasting pressure is 0.4~0.6MPa, and the sandblasting distance is 50~80mm, so that the roughness Ra of the PEEK surface reaches 3~5μm, thereby improving the adhesion between the coating and the substrate.

[0038] During the spraying process, the plasma arc current is set to 400~500A, the voltage is set to 60~80V, the powder feeding rate is set to 20~30g / min, the porosity of the coating needs to be controlled below 5%, and the bonding strength needs to reach 20~30MPa. The tests are verified by cross-cut test and tensile test. The surface hardness of the nano-ceramic coating needs to reach HV1200~1500, which is tested by Vickers hardness tester with a test load of 100g and a loading time of 10s.

[0039] Preferably, the process of embedding the drone hardware into the explosion-proof packaging structure specifically includes the following steps:

[0040] First, apply thermally conductive silicone to the bonding surface of the inner buffer layer. The thermal conductivity of the silicone should be set to 3~5 W / (m・K), the viscosity to be set to 5000~10000 mPa・s, and the coating thickness to be 0.1~0.2 mm. During the coating process, ensure that no air bubbles remain.

[0041] Then, the drone hardware is slowly embedded into the inner buffer layer. During the embedding process, uniform pressure is applied and maintained for 10-20 seconds to ensure that the hardware fits tightly into the inner buffer layer.

[0042] Next, the inner buffer layer embedded with the hardware is placed into the middle explosion-proof barrier layer. The inner wall of the middle explosion-proof barrier layer needs to be coated with high-temperature resistant sealant. The width of the sealant application is 5~10mm and the thickness is 0.2~0.3mm. Then, the inner buffer layer and the middle explosion-proof barrier layer are fixed by positioning clamps. The positioning accuracy is controlled within ±0.1mm. After fixing, it is placed at room temperature for 24~48h to allow the sealant to fully cure.

[0043] Finally, place the assembled inner and middle layers into the outer protective layer. The inner wall of the outer protective layer needs to be lined with cushioning foam to further improve the overall cushioning performance. After placement, fix the upper and lower shells of the outer protective layer with bolts. The bolts are made of titanium alloy with a diameter of 3-5mm and a tightening torque of 5-10N·m. During tightening, use a torque wrench to tighten in a diagonal sequence to avoid uneven force that could cause deformation of the outer protective layer.

[0044] Preferably, the laser welding technology uses a fiber laser with a wavelength set to 1064nm. Before welding, the splicing area of ​​the packaging structure needs to be cleaned by wiping the splicing surface with anhydrous ethanol to remove oil and impurities, and then drying it with compressed air.

[0045] Inert gas protection is used during welding. The flow rate of argon gas is set to 10~15L / min, and the distance between the protective gas nozzle and the welding point is set to 5~10mm to prevent oxidation of the welding area.

[0046] The welding trajectory is controlled by CNC programming according to the splicing shape of the packaging structure. The programming accuracy is controlled within ±0.01mm. For straight splicing sections, the welding speed is kept constant. For curved splicing sections, the welding speed is adjusted according to the curvature of the curve. When the radius of curvature is less than 10mm, the welding speed is reduced to 3~5mm / s.

[0047] After welding, the weld is inspected using ultrasonic testing equipment. The testing frequency is set to 5~10MHz, the probe angle is set to 45°~60°, and the inspection range covers the entire weld area to ensure that the weld is free of defects such as cracks, porosity, and lack of fusion. The defect area should account for less than 0.5% of the weld area. At the same time, the strength of the weld is tested using a tensile test method. The tensile speed is set to 1~2mm / min, and the tensile strength of the weld should reach more than 80% of the tensile strength of the outer layer material (PEEK) of the encapsulation structure.

[0048] Preferably, the airtightness detection uses helium mass spectrometry leak detection, and the specific detection steps are as follows:

[0049] Before testing, the packaged drone hardware must be placed in a sealed container, which is then filled with helium gas at a pressure of 0.3~0.5MPa for 30 minutes.

[0050] Then, the helium concentration outside the sealed container was detected using a helium mass spectrometer leak detector, with the minimum detectable leak rate of the detector set to 1×10⁻⁶. -12 Pa・m³ / s, if the detected leakage rate is less than 1×10 -9 If the pressure is Pa・m³ / s, the airtightness is deemed acceptable.

[0051] The explosion-proof performance test includes two test scenarios:

[0052] The first scenario simulates a battery short circuit fault. The positive and negative terminals of the drone battery are directly short-circuited through an external wire. The short circuit current is set to 5 to 10 times the rated current of the battery, and the duration is 5 to 10 seconds. During the test, a high-speed camera is used to observe whether there is flame or debris leakage in the packaging structure. At the same time, an infrared thermal imager is used to monitor the temperature distribution outside the packaging structure to ensure that the highest external temperature does not exceed 45°C.

[0053] The second scenario simulates a circuit overheating fault. The motor controller of the drone is heated by a heating device at a rate of 5-10℃ / min, so that the temperature of the motor controller reaches 150-200℃ for 10-20 minutes. Similarly, the status of the encapsulation structure is monitored by a high-speed camera and an infrared thermal imager to ensure that there is no flame or debris leakage and that the external temperature does not exceed 45℃.

[0054] This invention provides an explosion-proof packaging method for drone hardware. It has the following beneficial effects:

[0055] 1. This invention utilizes modified silicone rubber in the inner buffer layer, with its thickness precisely calculated using a formula, to attenuate impact stress by more than 80%. Simultaneously, a honeycomb-shaped heat dissipation channel is incorporated to address heat concentration issues. The middle explosion-proof barrier layer is made of alumina ceramic-silicon carbide fiber composite material, possessing an impact strength of 15-20 MPa and a flexural strength of 300-400 MPa, capable of withstanding explosive shock waves below 1.5 MPa. An internal stainless steel mesh reinforcement layer further enhances toughness, preventing brittle fracture. The outer protective layer employs polyetheretherketone (PEEK) + zirconium oxide nano-coating (HV1200-1500), offering wear resistance, corrosion resistance, and impact resistance. The three layers work synergistically to completely block flame and debris leakage. Under fault conditions, the external temperature is ≤45℃, resulting in a safety protection level more than three times higher than traditional packaging.

[0056] 2. This invention uses laser triangulation and finite element simulation to accurately locate areas of concentrated heat and weak stress points. The thickness of the buffer layer is dynamically adjusted according to the stress value, the heat dissipation channel matches the heat distribution, and the thickness of the explosion-proof barrier layer is calculated according to the shock wave pressure. This ensures that each protection link addresses hardware risks in a targeted manner, and the adaptability is improved by 80% compared to traditional general packaging.

[0057] 3. The silicone rubber of this invention is customized through intensive mixing (120~150℃) and vulcanization (160~180℃), with a bonding gap of <0.1mm; the ceramic matrix composite material adopts CVD coating, impregnation-winding molding and high-temperature sintering (1600~1800℃), with performance fluctuation ≤5%; laser welding (1500~2000W) combined with argon protection, with a weld defect rate of <0.5% and an airtightness leakage rate of <1×10⁻ 9 Pa・m³ / s, the process precision is improved by 2 orders of magnitude compared with the traditional method, and the packaging life is extended from 1 year to 3~5 years.

[0058] 4. The explosion-proof performance test of this invention simulates battery short circuit and circuit overheating, and combines high-speed camera and infrared thermal imager monitoring to ensure no risk of leakage; additional vibration (10~2000Hz, 15g) and impact (20g, 3ms) tests are conducted to verify stability in harsh environments; electrical performance testing ensures that the hardware function change rate is <5%, fully covers actual application scenarios, and improves the detection integrity by 100% compared with traditional methods, completely eliminating safety hazards. Attached Figure Description

[0059] Figure 1 This is an overview diagram of the core process of this invention;

[0060] Figure 2 This is a flowchart of the explosion-proof pretreatment process of the present invention;

[0061] Figure 3 This is a flowchart illustrating the preparation process of the inner buffer layer of this invention.

[0062] Figure 4 This is a flowchart illustrating the preparation process of the explosion-proof barrier layer in this invention.

[0063] Figure 5 This is a flowchart illustrating the preparation process of the outer protective layer of this invention.

[0064] Figure 6 This is a flowchart of the hardware embedded packaging structure of the present invention;

[0065] Figure 7 This is a flowchart of the laser welding and weld inspection process of the present invention;

[0066] Figure 8 This is a flowchart of the airtightness testing and explosion-proof performance testing of the present invention. Detailed Implementation

[0067] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0068] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0069] Example 1

[0070] A preferred embodiment of the explosion-proof packaging method for drone hardware provided by the present invention is as follows: Figures 1-8As shown: An explosion-proof packaging method for drone hardware includes the following steps:

[0071] Step 1: First, the drone hardware is subjected to explosion-proof pretreatment. This pretreatment process requires obtaining the outer contour data of the drone hardware through a 3D scanning device to generate a 3D model with an accuracy of 0.01mm. Then, the heat concentration areas and stress weak points on the surface of the hardware are analyzed based on the 3D model.

[0072] The determination of the heat concentration area needs to be based on the temperature field simulation results of the hardware under full load operation. The finite element analysis software is used to perform thermal simulation of the hardware, setting the ambient temperature to -40℃~60℃, the operating power to 110% of the hardware's rated power, and the simulation time to last 2 hours. The area with a temperature higher than 65℃ is extracted as the heat concentration area.

[0073] The determination of stress weak points is achieved by applying 1.2 times the rated vibration load (vibration frequency range 10Hz~2000Hz, acceleration 10g) and 1.5 times the rated impact load (impact time 5ms, impact force direction in XYZ triaxial direction) to the hardware, and extracting areas where the stress value exceeds 80% of the yield strength of the hardware material as stress weak points.

[0074] Step 2: Next, based on the heat concentration areas and stress weak points obtained from the pretreatment, a customized explosion-proof encapsulation structure is developed. This explosion-proof encapsulation structure includes an inner buffer layer, a middle explosion-proof barrier layer, and an outer protective layer.

[0075] The inner buffer layer is made of modified silicone rubber with a Shore A hardness of 35±5. Its thickness is determined by calculation based on the stress value at the weakest point. The specific calculation formula is as follows: ,in The thickness of the inner buffer layer (unit: mm). This represents the maximum stress value at the weakest point (unit: MPa). The stress-bearing area of ​​the weakest point (unit: mm²). The elastic modulus of modified silicone rubber (unit: MPa, value range: 1.2~1.8MPa). The stress attenuation that the buffer layer can withstand (unit: MPa, value is...) ×0.6);

[0076] The middle explosion-proof barrier layer is made of ceramic matrix composite material, which is woven from alumina ceramic particles and silicon carbide fibers. The alumina ceramic particles have a particle size of 50-100 μm and a volume percentage of 65%-75%, while the silicon carbide fibers have a diameter of 10-20 μm and a volume percentage of 25%-35%. The thickness of the middle explosion-proof barrier layer is determined based on the potential explosion shock wave pressure generated by the hardware, using the following formula: ,in The thickness of the middle explosion-proof barrier layer (unit: mm). To estimate the pressure of the explosion shock wave (unit: MPa, calculated based on the maximum energy density of the drone's hardware battery and circuitry, with a value range of 0.8~1.5 MPa). The duration of the shock wave (unit: ms, value is 5~10ms). The value represents the density of the ceramic matrix composite material (unit: g / cm³, ranging from 2.8 to 3.2 g / cm³). The propagation speed of the shock wave in the material (unit: m / s, value range: 3500~4500 m / s).

[0077] The outer protective layer is made of polyetheretherketone (PEEK) material with a thickness of 3-5 mm. The surface of the outer protective layer needs to be treated with a nano-ceramic coating. The coating material is zirconium oxide with a thickness of 5-10 μm. It is prepared by plasma spraying technology with a spraying power of 40-60 kW and a spraying distance of 100-150 mm to improve the wear resistance and corrosion resistance of the outer protective layer.

[0078] Step 3: Embed the drone hardware into the customized explosion-proof packaging structure. Use laser welding technology to seal the joints of the packaging structure. The laser welding power is set to 1500~2000W, the welding speed is 5~10mm / s, and the spot diameter is 0.5~1mm. After welding, perform an airtightness test on the packaging structure. The test pressure is 0.3~0.5MPa, and the pressure holding time is 30min, ensuring that the airtightness leakage rate is less than 1×10⁻⁶. -9 Pa・m³ / s, and simultaneously conduct explosion-proof performance tests, simulate hardware short circuits, overheating and other fault scenarios, verify that the packaging structure has no flame or fragment leakage under fault conditions, and the external temperature does not exceed 45℃.

[0079] Example 2

[0080] Please see Figures 1-8 Furthermore, based on Example 1, the following is obtained: When the UAV hardware undergoes explosion-proof preprocessing, the 3D scanning device adopts laser triangulation scanning technology, with a scanning speed set to 5000~8000 points / s and a scanning resolution of 0.005mm. During the scanning process, the hardware needs to be scanned in all directions at 360°, and a set of data is collected every 10°, for a total of 36 sets of data. The 36 sets of data are then fused together using a point cloud stitching algorithm to generate a complete 3D model. The point cloud stitching algorithm adopts the Iterative Closest Point (ICP) algorithm, with the number of iterations set to 50~100 times and the convergence threshold set to 0.001mm to ensure the accuracy of the 3D model.

[0081] During the temperature field simulation, the core hardware components (such as batteries, motor controllers, and central processing units) need to be modeled separately. The thermal physical parameters such as thermal conductivity and specific heat capacity of each core component are set. Specifically, the thermal conductivity of the battery is set to 0.8~1.2 W / (m·K), and the specific heat capacity is set to 1200~1500 J / (kg·K). The thermal conductivity of the motor controller is set to 150~200 W / (m·K), and the specific heat capacity is set to 450~500 J / (kg·K). The thermal conductivity of the central processing unit is set to 100~120 W / (m·K), and the specific heat capacity is set to 380~420 J / (kg·K). At the same time, heat dissipation paths are added to the simulation model to simulate the airflow heat dissipation during actual flight of the UAV. The airflow speed is set to 2~8 m / s to ensure that the temperature field simulation results are consistent with the actual operating conditions.

[0082] During the stress analysis, a dynamic stress analysis method is adopted. Vibration and impact loads are applied to the hardware model in a time sequence with a time step of 0.1ms. The stress distribution of the hardware at different time nodes is calculated through the transient dynamic analysis module, and the maximum stress value at each time node is extracted. Finally, the location and maximum stress value of the stress weak point are determined. Before the stress analysis, the hardware model needs to be meshed with a mesh cell size of 0.5~2mm to ensure that the mesh quality meets the standards (mesh distortion less than 5% and aspect ratio less than 10).

[0083] Further, it was found that the modified silicone rubber material used in the inner buffer layer was prepared by adding 20%~30% (mass fraction) of nano-calcium carbonate particles and 5%~10% (mass fraction) of flame retardant (decabromodiphenyl ether) to the base silicone rubber. The nano-calcium carbonate particles have a particle size of 20~50nm and are surface-treated with silane coupling agent (KH-550) at a temperature of 80~100℃ for 2~3h to improve the compatibility between the nano-calcium carbonate particles and the silicone rubber matrix.

[0084] The preparation process of modified silicone rubber specifically includes the following steps:

[0085] The base silicone rubber, nano calcium carbonate particles, and flame retardant are mixed in proportion and added to an internal mixer. The mixture is then mixed for 30 to 60 minutes at a temperature of 120 to 150°C and a speed of 50 to 80 r / min to obtain the mixed rubber compound.

[0086] The mixed rubber compound is transferred to a vulcanizing machine and vulcanized for 10-20 minutes at a temperature of 160-180℃ and a pressure of 10-15MPa to produce an inner buffer layer preform.

[0087] Finally, based on the dimensions of the hardware 3D model, the prefabricated parts are cut using CNC cutting equipment with a cutting precision controlled within ±0.05mm to ensure complete adhesion between the inner buffer layer and the hardware surface, with a gap of less than 0.1mm. Micro heat dissipation channels are opened on the surface of the inner buffer layer in contact with the hardware. The diameter of the heat dissipation channels is 0.5~1mm, the spacing is 5~10mm, and they are distributed in a honeycomb pattern to improve the heat dissipation efficiency of the heat concentration area. The total heat dissipation area of ​​the heat dissipation channels accounts for 15%~20% of the contact area of ​​the inner buffer layer. Through thermal resistance calculation verification, it is ensured that the heat dissipation channels can reduce the temperature of the heat concentration area by 8~15℃.

[0088] Further, it was found that the ceramic matrix composite material used in the middle explosion-proof barrier layer is prepared by the following steps:

[0089] First, silicon carbide fiber cloth is prepared by weaving silicon carbide fibers into cloth in the warp and weft directions with a weaving density of 20-30 fibers / cm and a fabric thickness of 0.2-0.3mm. Then, the silicon carbide fiber cloth is coated with boron nitride as the coating material with a coating thickness of 1-2μm. The coating is prepared by chemical vapor deposition (CVD) technology with a deposition temperature of 800-1000℃, a deposition pressure of 5-10kPa, and a deposition time of 2-3h to improve the bonding strength between the fiber and the ceramic matrix.

[0090] Next, an alumina ceramic slurry is prepared by mixing alumina ceramic particles, sintering aid (silicon dioxide and magnesium oxide in a mass ratio of 3:1) and binder (polyvinyl alcohol) in a mass ratio of 90:5:5, adding an appropriate amount of deionized water, and ball milling in a ball mill at a speed of 200~300 r / min for 4~6 hours to prepare a ceramic slurry with a solid content of 60%~70%.

[0091] Then, the ceramic slurry is coated onto silicon carbide fiber cloth using an impregnation-winding process, with a coating thickness of 0.1~0.2 mm / layer. After each layer is coated, it is dried at a temperature of 80~100℃ for 1~2 hours. The coating is repeated for 5~8 layers to obtain the composite material preform.

[0092] Finally, the composite material preform is placed in a sintering furnace and heated to 1600-1800℃ at a heating rate of 5-10℃ / min under inert gas (argon) protection, and held for 3-5 hours for sintering. After sintering, it is cooled to room temperature with the furnace to obtain the middle explosion-proof barrier layer. The impact strength of the middle explosion-proof barrier layer needs to reach 15-20MPa, and the flexural strength needs to reach 300-400MPa. The test is carried out by a universal testing machine with a test speed set at 2-5mm / min. A metal mesh reinforcement layer is set inside the middle explosion-proof barrier layer. The metal mesh is made of stainless steel with a mesh size of 1-2mm and a thickness of 0.1-0.2mm. The metal mesh and ceramic matrix composite material are combined by hot pressing composite process. The hot pressing temperature is 1200-1400℃, the hot pressing pressure is 20-30MPa, and the hot pressing time is 1-2 hours to improve the toughness of the middle explosion-proof barrier layer and prevent it from brittle fracture under impact.

[0093] Further findings indicate that the outer protective layer, made of polyetheretherketone (PEEK) material, requires drying before processing. The drying temperature is 120-150℃, and the drying time is 4-6 hours to remove moisture from the material and prevent air bubbles from forming during processing. The outer protective layer is prepared using injection molding, and the specific preparation process includes the following steps:

[0094] First, the barrel temperature of the injection molding machine is set to 340~380℃ (front section temperature 340~350℃, middle section temperature 350~360℃, rear section temperature 360~380℃), the mold temperature is set to 120~150℃, the injection pressure is set to 80~120MPa, the injection speed is set to 50~100mm / s, the holding pressure is set to 60~80MPa, the holding time is set to 5~10s, and the cooling time is set to 20~30s to ensure the molding quality of the outer protective layer.

[0095] The outer protective layer after molding needs to undergo stress relief treatment. The treatment temperature is 160~180℃, the treatment time is 2~3h, and the cooling rate is 5~10℃ / h, in order to eliminate the internal stress generated during injection molding and avoid cracking during subsequent use.

[0096] The nano-ceramic coating (zirconia) on the surface of the outer protective layer is prepared by atmospheric plasma spraying technology. Before spraying, the PEEK surface needs to be sandblasted. The sandblasting medium is alumina sand with a particle size of 80~120 mesh, the sandblasting pressure is 0.4~0.6MPa, and the sandblasting distance is 50~80mm, so that the roughness Ra of the PEEK surface reaches 3~5μm, thereby improving the adhesion between the coating and the substrate.

[0097] During the spraying process, the plasma arc current is set to 400~500A, the voltage is set to 60~80V, the powder feeding rate is set to 20~30g / min, the porosity of the coating needs to be controlled below 5%, and the bonding strength needs to reach 20~30MPa. The tests are verified by cross-cut test and tensile test. The surface hardness of the nano-ceramic coating needs to reach HV1200~1500, which is tested by Vickers hardness tester with a test load of 100g and a loading time of 10s.

[0098] Further analysis reveals that the process of embedding drone hardware into an explosion-proof packaging structure specifically includes the following steps:

[0099] First, apply thermally conductive silicone to the bonding surface of the inner buffer layer. The thermal conductivity of the silicone should be set to 3~5 W / (m・K), the viscosity to be set to 5000~10000 mPa・s, and the coating thickness to be 0.1~0.2 mm. During the coating process, ensure that no air bubbles remain.

[0100] Then, the drone hardware is slowly embedded into the inner buffer layer. During the embedding process, uniform pressure (0.5~1MPa) is applied and maintained for 10~20 seconds to ensure that the hardware and the inner buffer layer fit tightly together.

[0101] Next, the inner buffer layer embedded with the hardware is placed into the middle explosion-proof barrier layer. The inner wall of the middle explosion-proof barrier layer needs to be coated with high-temperature resistant sealant (temperature range -60℃~300℃). The width of the sealant application is 5~10mm and the thickness is 0.2~0.3mm. Then, the inner buffer layer and the middle explosion-proof barrier layer are fixed by positioning clamps. The positioning accuracy is controlled within ±0.1mm. After fixing, it is placed at room temperature for 24~48h to allow the sealant to fully cure.

[0102] Finally, place the assembled inner and middle layers into the outer protective layer. The inner wall of the outer protective layer needs to be lined with cushioning foam (made of polyurethane, with a density of 30~50kg / m³ and a thickness of 1~2mm) to further improve the overall cushioning performance. After placement, fix the upper and lower shells of the outer protective layer with bolts. The bolts are made of titanium alloy, with a diameter of 3~5mm, and the tightening torque is set to 5~10N・m. During the tightening process, use a torque wrench to tighten in a diagonal sequence to avoid uneven force that could cause deformation of the outer protective layer.

[0103] Further findings revealed that the laser welding technology uses a fiber laser with a wavelength set at 1064nm. Before welding, the splicing area of ​​the packaging structure needs to be cleaned by wiping the splicing surface with anhydrous ethanol to remove oil and impurities, and then drying it with compressed air.

[0104] Inert gas (argon) is used for protection during welding. The flow rate of argon is set to 10~15L / min, and the distance between the protective gas nozzle and the welding point is set to 5~10mm to prevent oxidation of the welding area.

[0105] The welding trajectory is controlled by CNC programming according to the splicing shape of the packaging structure, with programming accuracy controlled within ±0.01mm. For straight splicing sections, the welding speed is kept constant (5~10mm / s). For curved splicing sections, the welding speed is adjusted according to the curvature of the curve. When the radius of curvature is less than 10mm, the welding speed is reduced to 3~5mm / s to ensure welding quality.

[0106] After welding, the weld is inspected using ultrasonic testing equipment. The testing frequency is set to 5~10MHz, the probe angle is set to 45°~60°, and the inspection range covers the entire weld area to ensure that the weld is free of defects such as cracks, porosity, and lack of fusion. The defect area must account for less than 0.5% of the weld area. At the same time, the strength of the weld is tested using a tensile test method. The tensile speed is set to 1~2mm / min. The tensile strength of the weld must reach more than 80% of the tensile strength of the outer layer material (PEEK) of the encapsulation structure (PEEK tensile strength is 90~100MPa, so the tensile strength of the weld must be ≥72MPa).

[0107] Further findings indicate that the airtightness test employed helium mass spectrometry leak detection, with the specific testing steps as follows:

[0108] Before testing, the packaged drone hardware must be placed in a sealed container, which is then filled with helium gas at a pressure of 0.3~0.5MPa for 30 minutes.

[0109] Then, the helium concentration outside the sealed container was detected using a helium mass spectrometer leak detector, with the minimum detectable leak rate of the detector set to 1×10⁻⁶. -12 Pa・m³ / s, if the detected leakage rate is less than 1×10 -9 If the pressure is Pa・m³ / s, the airtightness is deemed acceptable.

[0110] The explosion-proof performance test includes two test scenarios:

[0111] The first scenario simulates a battery short circuit fault. The positive and negative terminals of the drone battery are directly short-circuited through an external wire. The short-circuit current is set to 5 to 10 times the rated current of the battery, and the duration is 5 to 10 seconds. During the test, a high-speed camera (shooting frame rate of 1000 to 2000 frames / s) is used to observe whether there is flame or debris leakage in the packaging structure. At the same time, an infrared thermal imager (temperature measurement range -20℃ to 300℃, temperature measurement accuracy ±1℃) is used to monitor the temperature distribution outside the packaging structure to ensure that the highest external temperature does not exceed 45℃.

[0112] The second scenario simulates a circuit overheating fault. A heating device is used to heat the drone's motor controller at a rate of 5-10°C / min, raising its temperature to 150-200°C (exceeding its normal operating temperature limit of 50-100°C) for 10-20 minutes. A high-speed camera and infrared thermal imager monitor the packaging structure to ensure no flame or debris leakage and that the external temperature does not exceed 45°C. Furthermore, vibration and shock tests are performed on the packaged drone hardware. Vibration test conditions are: frequency range 10Hz-2000Hz, acceleration 15g, vibration time 2 hours (40 minutes each for the XYZ axes). Shock test conditions are: impact acceleration 20g, impact time 3ms, 3 impacts each for the XYZ axes. After testing, the packaging structure is disassembled to check for hardware damage, and the electrical performance (such as voltage, current, and signal transmission efficiency) is tested to ensure the rate of change in electrical performance indicators is less than 5%, verifying the reliability of the explosion-proof packaging structure in harsh environments.

[0113] When using it, ...

[0114] In conclusion, ...

[0115] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0116] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for explosion-proof packaging of unmanned aerial vehicle (UAV) hardware, characterized in that, Includes the following steps: Step 1: First, the drone hardware is subjected to explosion-proof pretreatment. This pretreatment process requires obtaining the outer contour data of the drone hardware through a 3D scanning device to generate a 3D model with an accuracy of 0.01mm. Then, the heat concentration areas and stress weak points on the surface of the hardware are analyzed based on the 3D model. The determination of the heat concentration area needs to be based on the temperature field simulation results of the hardware under full load operation. The finite element analysis software is used to perform thermal simulation of the hardware, setting the ambient temperature to -40℃~60℃, the operating power to 110% of the hardware's rated power, and the simulation time to last 2 hours. The area with a temperature higher than 65℃ is extracted as the heat concentration area. The determination of stress weak points is achieved by applying 1.2 times the rated vibration load and 1.5 times the rated impact load to the hardware, and extracting areas where the stress value exceeds 80% of the yield strength of the hardware material as stress weak points. Step 2: Next, based on the heat concentration areas and stress weak points obtained from the pretreatment, a customized explosion-proof encapsulation structure is developed. This explosion-proof encapsulation structure includes an inner buffer layer, a middle explosion-proof barrier layer, and an outer protective layer. The inner buffer layer is made of modified silicone rubber with a Shore A hardness of 35±5. Its thickness is determined by calculation based on the stress value at the weakest point, using the following formula: in The thickness of the inner buffer layer. This represents the maximum stress value at the weakest point. The stress-bearing area of ​​the weakest point. The elastic modulus of modified silicone rubber, This represents the amount of stress attenuation that the buffer layer can withstand. The middle explosion-proof barrier layer is made of ceramic matrix composite material, which is woven from alumina ceramic particles and silicon carbide fibers. The alumina ceramic particles have a particle size of 50-100 μm and a volume percentage of 65%-75%, while the silicon carbide fibers have a diameter of 10-20 μm and a volume percentage of 25%-35%. The thickness of the middle explosion-proof barrier layer is determined based on the potential explosion shock wave pressure generated by the hardware, using the following formula: in The thickness of the middle explosion-proof barrier layer, To predict the pressure of the explosion shock wave, The duration of the shock wave. The density of the ceramic matrix composite material. This refers to the propagation speed of the shock wave within the material. The outer protective layer is made of polyetheretherketone material with a thickness of 3-5 mm. The surface of the outer protective layer needs to be treated with a nano-ceramic coating. The coating material is zirconium oxide with a thickness of 5-10 μm. It is prepared by plasma spraying technology with a spraying power of 40-60 kW and a spraying distance of 100-150 mm. Step 3: Embed the drone hardware into the customized explosion-proof packaging structure. Use laser welding technology to seal the joints of the packaging structure. The laser welding power is set to 1500~2000W, the welding speed is 5~10mm / s, and the spot diameter is 0.5~1mm. After welding, perform an airtightness test on the packaging structure. The test pressure is 0.3~0.5MPa, and the pressure holding time is 30min, ensuring that the airtightness leakage rate is less than 1×10⁻⁶. -9 Pa・m³ / s, and simultaneously conduct explosion-proof performance tests, simulate hardware short circuits, overheating and other fault scenarios, verify that the packaging structure has no flame or fragment leakage under fault conditions, and the external temperature does not exceed 45℃.

2. The explosion-proof packaging method for UAV hardware according to claim 1, characterized in that: When the UAV hardware undergoes explosion-proof preprocessing, the 3D scanning device uses laser triangulation scanning technology with a scanning speed of 5000~8000 points / s and a scanning resolution of 0.005mm. During the scanning process, the hardware needs to be scanned in all directions of 360°, and a set of data is collected every 10°, for a total of 36 sets of data. The 36 sets of data are then fused together using a point cloud stitching algorithm to generate a complete 3D model. The point cloud stitching algorithm uses the Iterative Closest Point (ICP) algorithm, with the number of iterations set to 50~100 times and the convergence threshold set to 0.001mm to ensure the accuracy of the 3D model. During the temperature field simulation, the core components of the hardware need to be modeled separately, and the thermal physical parameters such as thermal conductivity and specific heat capacity of each core component are set. The thermal conductivity of the battery is set to 0.8~1.2W / (m·K) and the specific heat capacity is set to 1200~1500J / (kg·K). The thermal conductivity of the motor controller is set to 150~200W / (m·K) and the specific heat capacity is set to 450~500J / (kg·K). The thermal conductivity of the central processing unit is set to 100~120W / (m·K) and the specific heat capacity is set to 380~420J / (kg·K). At the same time, heat dissipation paths are added to the simulation model to simulate the airflow heat dissipation during the actual flight of the UAV. The airflow speed is set to 2~8m / s. During the stress analysis, a dynamic stress analysis method is adopted, in which vibration and impact loads are applied to the hardware model in a time sequence with a time step of 0.1ms. The stress distribution of the hardware at different time nodes is calculated through the transient dynamic analysis module, the maximum stress value at each time node is extracted, and the location and maximum stress value of the stress weak point are finally determined. Before the stress analysis, the hardware model needs to be meshed, and the mesh element size is set to 0.5~2mm.

3. The explosion-proof packaging method for UAV hardware according to claim 1, characterized in that: The modified silicone rubber material used in the inner buffer layer is prepared by adding 20%~30% (mass fraction) of nano-calcium carbonate particles and 5%~10% (mass fraction) of flame retardant to the base silicone rubber. The nano-calcium carbonate particles have a particle size of 20~50nm and are surface treated with silane coupling agent at a temperature of 80~100℃ for 2~3h. The preparation process of modified silicone rubber specifically includes the following steps: The base silicone rubber, nano calcium carbonate particles, and flame retardant are mixed in proportion and added to an internal mixer. The mixture is then mixed for 30 to 60 minutes at a temperature of 120 to 150°C and a speed of 50 to 80 r / min to obtain the mixed rubber compound. The mixed rubber compound is transferred to a vulcanizing machine and vulcanized for 10-20 minutes at a temperature of 160-180℃ and a pressure of 10-15MPa to produce an inner buffer layer preform. Finally, based on the dimensions of the hardware 3D model, the prefabricated parts are cut using CNC cutting equipment with a cutting accuracy controlled within ±0.05mm. Micro heat dissipation channels are opened on the surface of the inner buffer layer that contacts the hardware. The diameter of the heat dissipation channels is 0.5~1mm, the spacing is 5~10mm, and they are distributed in a honeycomb pattern.

4. The explosion-proof packaging method for UAV hardware according to claim 1, characterized in that: The ceramic-based composite material used in the middle explosion-proof barrier layer is prepared through the following steps: First, silicon carbide fiber cloth is prepared by weaving silicon carbide fibers into cloth in the warp and weft directions with a weaving density of 20-30 fibers / cm and a fabric thickness of 0.2-0.3mm. Then, the silicon carbide fiber cloth is coated with boron nitride as the coating material with a coating thickness of 1-2μm. The coating is prepared by chemical vapor deposition (CVD) technology with a deposition temperature of 800-1000℃, a deposition pressure of 5-10kPa, and a deposition time of 2-3h. Next, an alumina ceramic slurry is prepared by mixing alumina ceramic particles, sintering aid, and binder in a mass ratio of 90:5:5, adding an appropriate amount of deionized water, and ball milling in a ball mill at a speed of 200~300 r / min for 4~6 hours to prepare a ceramic slurry with a solid content of 60%~70%. Then, the ceramic slurry is coated onto silicon carbide fiber cloth using an impregnation-winding process, with a coating thickness of 0.1~0.2 mm / layer. After each layer is coated, it is dried at a temperature of 80~100℃ for 1~2 hours. The coating is repeated for 5~8 layers to obtain the composite material preform. Finally, the composite material preform is placed in a sintering furnace and heated to 1600-1800℃ at a heating rate of 5-10℃ / min under inert gas (argon) protection, and held for 3-5 hours for sintering. After sintering, it is cooled to room temperature with the furnace to obtain the middle explosion-proof barrier layer. The impact strength of the middle explosion-proof barrier layer needs to reach 15-20MPa, and the flexural strength needs to reach 300-400MPa. The test is carried out by a universal testing machine with a test speed set at 2-5mm / min. A metal mesh reinforcement layer is set inside the middle explosion-proof barrier layer. The metal mesh is made of stainless steel with a mesh size of 1-2mm and a thickness of 0.1-0.2mm. The metal mesh and the ceramic matrix composite material are combined by hot pressing. The hot pressing temperature is 1200-1400℃, the hot pressing pressure is 20-30MPa, and the hot pressing time is 1-2 hours.

5. The explosion-proof packaging method for UAV hardware according to claim 1, characterized in that: The outer protective layer uses polyetheretherketone (PEEK) material, which needs to be dried before processing. The drying temperature is 120~150℃, and the drying time is 4~6 hours to remove moisture from the material and prevent air bubbles from forming during processing. The outer protective layer is prepared by injection molding, and the specific preparation process includes the following steps: First, set the injection molding machine's barrel temperature to 340~380℃ (front section temperature 340~350℃, middle section temperature 350~360℃, rear section temperature 360~380℃), mold temperature to 120~150℃, injection pressure to 80~120MPa, injection speed to 50~100mm / s, holding pressure to 60~80MPa, holding time to 5~10s, and cooling time to 20~30s. The outer protective layer after molding needs to undergo stress relief treatment. The treatment temperature is 160~180℃, the treatment time is 2~3h, and the cooling rate is 5~10℃ / h, in order to eliminate the internal stress generated during the injection molding process. The nano-ceramic coating on the surface of the outer protective layer is prepared using atmospheric plasma spraying technology. Before spraying, the PEEK surface needs to be sandblasted. The sandblasting medium is alumina sand with a particle size of 80~120 mesh, the sandblasting pressure is 0.4~0.6MPa, and the sandblasting distance is 50~80mm, so that the roughness Ra of the PEEK surface reaches 3~5μm, thereby improving the adhesion between the coating and the substrate. During the spraying process, the plasma arc current is set to 400~500A, the voltage is set to 60~80V, the powder feeding rate is set to 20~30g / min, the porosity of the coating needs to be controlled below 5%, and the bonding strength needs to reach 20~30MPa. The tests are verified by cross-cut test and tensile test. The surface hardness of the nano-ceramic coating needs to reach HV1200~1500, which is tested by Vickers hardness tester with a test load of 100g and a loading time of 10s.

6. The explosion-proof packaging method for UAV hardware according to claim 1, characterized in that: The process of embedding the drone hardware into the explosion-proof packaging structure specifically includes the following steps: First, apply thermally conductive silicone to the bonding surface of the inner buffer layer. The thermal conductivity of the silicone should be set to 3~5 W / (m・K), the viscosity to be set to 5000~10000 mPa・s, and the coating thickness to be 0.1~0.2 mm. During the coating process, ensure that no air bubbles remain. Then, the drone hardware is slowly embedded into the inner buffer layer. During the embedding process, uniform pressure is applied and maintained for 10-20 seconds to ensure that the hardware fits tightly into the inner buffer layer. Next, the inner buffer layer embedded with the hardware is placed into the middle explosion-proof barrier layer. The inner wall of the middle explosion-proof barrier layer needs to be coated with high-temperature resistant sealant. The width of the sealant application is 5~10mm and the thickness is 0.2~0.3mm. Then, the inner buffer layer and the middle explosion-proof barrier layer are fixed by positioning clamps. The positioning accuracy is controlled within ±0.1mm. After fixing, it is placed at room temperature for 24~48h to allow the sealant to fully cure. Finally, place the assembled inner and middle layers into the outer protective layer. The inner wall of the outer protective layer needs to be lined with cushioning foam to further improve the overall cushioning performance. After placement, fix the upper and lower shells of the outer protective layer with bolts. The bolts are made of titanium alloy with a diameter of 3-5mm and a tightening torque of 5-10N·m. During tightening, use a torque wrench to tighten in a diagonal sequence to avoid uneven force that could cause deformation of the outer protective layer.

7. The explosion-proof packaging method for UAV hardware according to claim 1, characterized in that: The laser welding technology uses a fiber laser with a wavelength set to 1064nm. Before welding, the splicing area of ​​the packaging structure needs to be cleaned. The splicing surface is wiped with anhydrous ethanol to remove oil and impurities, and then dried with compressed air. Inert gas protection is used during welding. The flow rate of argon gas is set to 10~15L / min, and the distance between the protective gas nozzle and the welding point is set to 5~10mm to prevent oxidation of the welding area. The welding trajectory is controlled by CNC programming according to the splicing shape of the packaging structure. The programming accuracy is controlled within ±0.01mm. For straight splicing sections, the welding speed is kept constant. For curved splicing sections, the welding speed is adjusted according to the curvature of the curve. When the radius of curvature is less than 10mm, the welding speed is reduced to 3~5mm / s. After welding, the weld is inspected using ultrasonic testing equipment. The testing frequency is set to 5~10MHz, the probe angle is set to 45°~60°, and the inspection range covers the entire weld area to ensure that the weld is free of defects such as cracks, porosity, and lack of fusion. The defect area should account for less than 0.5% of the weld area. At the same time, the strength of the weld is tested using a tensile test method. The tensile speed is set to 1~2mm / min, and the tensile strength of the weld should reach more than 80% of the tensile strength of the outer layer material (PEEK) of the encapsulation structure.

8. The explosion-proof packaging method for UAV hardware according to claim 1, characterized in that: The airtightness test employs helium mass spectrometry leak detection, and the specific testing steps are as follows: Before testing, the packaged drone hardware must be placed in a sealed container, which is then filled with helium gas at a pressure of 0.3~0.5MPa for 30 minutes. Then, the helium concentration outside the sealed container was detected using a helium mass spectrometer leak detector, with the minimum detectable leak rate of the detector set to 1×10⁻⁶. -12 Pa・m³ / s, if the detected leakage rate is less than 1×10 -9 If the pressure is Pa・m³ / s, the airtightness is deemed acceptable. The explosion-proof performance test includes two test scenarios: The first scenario simulates a battery short circuit fault. The positive and negative terminals of the drone battery are directly short-circuited through an external wire. The short circuit current is set to 5 to 10 times the rated current of the battery, and the duration is 5 to 10 seconds. During the test, a high-speed camera is used to observe whether there is flame or debris leakage in the packaging structure. At the same time, an infrared thermal imager is used to monitor the temperature distribution outside the packaging structure to ensure that the highest external temperature does not exceed 45°C. The second scenario simulates a circuit overheating fault. The motor controller of the drone is heated by a heating device at a rate of 5-10℃ / min, so that the temperature of the motor controller reaches 150-200℃ for 10-20 minutes. Similarly, the status of the encapsulation structure is monitored by a high-speed camera and an infrared thermal imager to ensure that there is no flame or debris leakage and that the external temperature does not exceed 45℃.

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