Method of designing a trans-medium vehicle and trans-medium vehicle

Abstract

The application discloses a design method of a cross-medium vehicle and the cross-medium vehicle. The design method of the cross-medium vehicle comprises the following steps: providing a vehicle semi-finished product; obtaining expected cross-medium conditions and a preset load reduction standard; setting rheological parameters of a variable-damping liquid as to-be-solved items, and solving the rheological parameters under the conditions that the expected cross-medium conditions and a load model meet the preset load reduction standard; obtaining the variable-damping liquid according to the rheological parameters and injecting the variable-damping liquid into a piston cylinder to obtain a vehicle assembly; performing a cross-medium test on the vehicle assembly under the expected cross-medium conditions, obtaining test data of impact load of the vehicle body changing with time, and judging whether the preset load reduction standard is met; and replacing an elastic reset part with different damping performance according to a judgment result until the preset load reduction standard is met. According to the embodiment of the application, the cross-medium vehicle can adaptively reduce load at different water entry speeds, and can meet the water entry load reduction requirement of the cross-medium vehicle in multiple cross-medium processes.

Description

Technical Field

[0001] This application relates to the field of cross-medium vehicle technology, and more particularly to a design method for a cross-medium vehicle and a cross-medium vehicle. Background Technology

[0002] When a cross-medium vehicle (such as an air-dropped torpedo or a cross-medium drone) enters water from the air, it experiences an extremely violent "water entry shock." This shock load is characterized by a high peak value, short rise time (milliseconds), and high-frequency nonlinearity, which can easily lead to deformation of the vehicle's outer shell structure, malfunction of internal high-precision sensors, or damage to electronic components. Related technologies employ elastic buffer structures to reduce the water entry load on cross-medium vehicles, or use sacrificial buffer materials or broken outer shells to absorb energy and achieve the same effect.

[0003] However, in related technologies, the use of elastic buffer structures to achieve water entry load reduction is not effective in a wide range of water entry velocities. Using sacrificial buffer materials or broken shells to achieve water entry load reduction cannot meet the water entry load reduction requirements of cross-medium vehicles in multiple cross-medium processes. Summary of the Invention

[0004] This application provides a design method for a cross-medium vehicle and a cross-medium vehicle, which enables the cross-medium vehicle to adapt to different water entry velocities for load reduction and can meet the water entry load reduction requirements of the cross-medium vehicle in multiple cross-medium processes.

[0005] On one hand, embodiments of this application provide a design method for a transmedium-based vehicle, comprising: providing a semi-finished vehicle, the semi-finished vehicle including a vehicle body, a nose cone body, and a variable damping component, the variable damping component being connected between the vehicle body and the nose cone body, the variable damping component including a piston cylinder and a piston plate movably disposed within the piston cylinder along a first direction, the piston cylinder being used to contain variable damping fluid, one of the piston plate and the piston cylinder being connected to the vehicle body, and the other being connected to the nose cone body; obtaining expected transmedium conditions and a preset load reduction standard; setting the rheological parameters of the variable damping fluid contained in the piston cylinder as a solution term, and under the expected transmedium conditions... The process involves obtaining a load model of the impact load on the vehicle body over time; solving for the rheological parameters under the condition that the load model meets the preset load reduction criteria; obtaining a variable damping fluid based on the rheological parameters; injecting the variable damping fluid into the piston cylinder and connecting the elastic reset component between the vehicle body and the nose cone body to obtain the vehicle assembly; conducting a cross-medium test on the vehicle assembly under the expected cross-medium conditions to obtain test data of the impact load on the vehicle body over time, determining whether the test data meets the preset load reduction criteria, and replacing the elastic reset component with different damping performance according to the determination result until the test data meets the preset load reduction criteria.

[0006] In some embodiments, the step of setting the rheological parameters of the variable damping fluid contained in the piston cylinder as the solution term, and obtaining the load model of the impact load on the vehicle body as a function of time under the expected transmedium conditions includes: setting the rheological parameters of the variable damping fluid contained in the piston cylinder as the solution term, obtaining a variable damping mechanical model with rheological parameters, the variable damping mechanical model being used to calculate the damping force applied by the variable damping fluid contained in the piston cylinder to the vehicle body and the nose cone body respectively through the variable damping component; determining the expected impact force on the nose cone body of the semi-finished vehicle under the expected transmedium conditions; performing a force analysis on the semi-finished vehicle under the expected transmedium conditions to obtain the force equations for the nose cone body and the vehicle body; and substituting the variable damping mechanical model and the expected impact force into the force equations to obtain the load model of the impact load on the vehicle body as a function of time.

[0007] In some embodiments, the expected cross-medium conditions include the expected velocity and the medium density. Under the expected cross-medium conditions, the step of determining the expected impact force on the hood body of the semi-finished vehicle includes: acquiring an impact force model, which is used to calculate the expected impact force; acquiring structural data of the hood body; determining the force-bearing area variable of the impact force model based on the structural data; determining the velocity variable of the impact force model based on the expected velocity; and determining the density variable of the impact force model based on the medium density.

[0008] In some embodiments, the anticipated cross-medium condition further includes a cross-medium angle, and the structural data includes the outer contour shape information and bottom area of ​​the headgear body. The step of determining the force area variable of the impact force model based on the structural data includes: determining the force angle variable of the force area variable based on the cross-medium angle, determining the headgear shape coefficient of the force area variable based on the outer contour shape information, and determining the base area variable of the force area variable based on the bottom area.

[0009] In some embodiments, the preset load reduction criteria include a preset upper limit for peak load and a preset upper limit for load change frequency. The step of replacing the elastic reset component with different damping performance according to the judgment result includes: if the judgment result shows that the peak load of the test data is greater than the preset upper limit for peak load, then the damping performance of the elastic reset component is reduced; if the judgment result shows that the frequency of load change over time in the test data is greater than the preset upper limit for load change frequency, then the damping performance of the elastic reset component is increased.

[0010] In some embodiments, the step of obtaining a variable damping fluid based on rheological parameters includes: preparing a variable damping fluid; performing a rheological test on the variable damping fluid to determine whether the variable damping fluid meets the rheological parameters; if the variable damping fluid does not meet the rheological parameters, adjusting the component ratio of the variable damping fluid and preparing it again until the variable damping fluid meets the rheological parameters.

[0011] In some embodiments, the preset load reduction criteria include a preset peak load limit and a preset load change frequency limit, and the rheological parameters include the viscosity coefficient and the velocity index.

[0012] On the other hand, embodiments of this application provide a transmedium vehicle, which is obtained by the design method of the transmedium vehicle provided above. The transmedium vehicle includes: a vehicle body; a helmet body, which is movably disposed on one side of the vehicle body along a first direction; a variable damping member, which is located and connected between the vehicle body and the helmet body along the first direction, the variable damping member including a piston cylinder and a piston plate, the piston cylinder being used to contain variable damping fluid, the piston plate being movably disposed in the piston cylinder along the first direction, one of the piston plate and the piston cylinder being connected to the vehicle body, and the other being connected to the helmet body; and an elastic reset member, which is located and connected between the vehicle body and the helmet body along the first direction, to apply a reset force away from the vehicle body along the first direction to the helmet body.

[0013] In some embodiments, the piston cylinder includes: an adapter connected to the vehicle body; and a piston cover disposed on the side of the adapter opposite to the vehicle body, the piston cover being connected to the adapter and forming the piston cylinder.

[0014] In some embodiments, the variable damping element further includes: a piston rod connected between the head cap body and the piston plate; a first sealed bearing sleeved on the piston rod, the inner ring of the first sealed bearing being connected to the piston rod, and the outer ring of the first sealed bearing being connected to the piston cover.

[0015] In some embodiments, the adapter has a mounting groove coaxially disposed with the piston rod, one end of the piston rod away from the head cap body along a first direction can extend into the mounting groove along the first direction, and an elastic reset member is disposed in the mounting groove, the elastic reset member being connected to the piston rod and the adapter respectively.

[0016] In some embodiments, the variable damping element further includes: a second sealed bearing sleeved on the piston rod, the inner ring of the second sealed bearing being connected to the piston rod, and the outer ring of the second sealed bearing being connected to the adapter.

[0017] In some embodiments, the piston plate has at least one through hole disposed along a first direction; and / or, the elastic reset member includes at least one of a mechanical spring and a gas spring.

[0018] In some embodiments, the variable damping element and the elastic reset element are connected in series between the vehicle body and the hood body; or, the variable damping element and the elastic reset element are connected in parallel between the vehicle body and the hood body.

[0019] In some embodiments, both the variable damping element and the elastic reset element are detachably connected to the head cap body; and / or, both the variable damping element and the elastic reset element are detachably connected to the vehicle body.

[0020] This application provides a design method for a cross-medium vehicle. By adjusting the damping performance of the elastic reset component and the rheological parameters of the variable damping fluid, it adapts to the set expected cross-medium conditions and preset load reduction criteria. When the cross-medium vehicle is introduced into the water, under impact load, the head cap body and piston plate gain impact kinetic energy, moving relative to the piston cylinder in a first direction close to the vehicle body. This compresses the elastic reset component and simultaneously squeezes the variable damping fluid inside the piston cylinder. The viscosity of the variable damping fluid passively responds to changes in the piston plate's velocity relative to the piston cylinder, thus enabling the cross-medium vehicle to... The cross-medium vehicle can adapt to different water entry velocities for load reduction. The impact kinetic energy can be converted into the internal energy of the variable damping fluid for dissipation, and also into the elastic potential energy of the elastic reset component for temporary storage. This continues until the relative velocity of the piston plate relative to the piston cylinder reaches zero. The elastic reset component then releases its stored elastic potential energy, propelling the nose cone body and piston plate relative to the piston cylinder along a first direction away from the vehicle body. Under the reset force of the elastic reset component, the nose cone body and piston plate gradually return to their original positions. During this return process, the variable damping fluid continues to provide variable damping force until the nose cone body and piston plate return to their initial positions before the impact load, and the residual energy is completely dissipated. Therefore, the cross-medium vehicle designed using this method can adapt to different water entry velocities for load reduction and can meet the water entry and load reduction requirements of cross-medium vehicles in multiple cross-medium processes. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A flowchart of steps S100 to S700 of a design method for a transmedia vehicle according to some embodiments of this application; Figure 2 This is a schematic diagram of the structure of a transmedium vehicle in some embodiments of this application, in which variable damping elements and elastic reset elements are connected in series. Figure 3 This is a schematic diagram of step S700 of some embodiments of the present application, which involves conducting a cross-medium test on the vehicle assembly under expected cross-medium conditions. Figure 4 A flowchart of steps S310 to S340 of a design method for a cross-medium vehicle according to some embodiments of this application; Figure 5 This is a schematic diagram illustrating step S330 of some embodiments of this application, which involves performing a force analysis on a semi-finished vehicle under expected cross-medium conditions. Figure 6Flowcharts of steps S321 and S322 of the design method for a cross-medium vehicle according to some embodiments of this application; Figure 7 Flowcharts of steps S510 and S530 of a design method for a transmedia vehicle according to some embodiments of this application; Figure 8 This is a schematic diagram of steps S500 to S700 of some embodiments of this application; Figure 9 This is a schematic diagram of the structure of the cap body and piston rod in some embodiments of this application; Figure 10 This is a schematic diagram of the structure of a first or second sealed bearing according to some embodiments of this application; Figure 11 This is a schematic diagram of the piston plate structure in some embodiments of this application; Figure 12 This is a schematic diagram of the structure of the adapter according to some embodiments of this application; Figure 13 This is a schematic diagram of the structure of a transmedium vehicle in which variable damping elements and elastic reset elements are connected in parallel according to some embodiments of this application.

[0023] The above figures include the following reference numerals: 1. Aircraft assembly; 10. The aircraft itself; 20. Head cap body; 21. Bottom surface; 30. Variable damping component; 31. Piston cylinder; 311. Adapter; 3111. Mounting groove; 3112. First threaded section; 3113. Second threaded section; 312. Piston cover; 32. Piston plate; 321. Through hole; 33. Variable damping fluid; 34. Piston rod; 341. Threaded section; 35. First sealed bearing; 36. Second sealed bearing; 40. Elastic reset component; 50. Medium to be introduced; V, expected velocity; F, expected impact force; F1, first damping force; F2, second damping force; X, first direction. Detailed Implementation

[0024] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0025] It should be noted that, in this document, relational terms such as "first" and "second" are used merely 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 a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0026] Currently, to achieve water entry load reduction for cross-medium vehicles, some solutions adopt a rigid shell structure, relying on the structural strength of the rigid shell structure to resist the impact load of water entry; some solutions adopt an elastic buffer structure, utilizing the deformation of the elastic buffer structure to achieve a buffering effect; and some solutions adopt sacrificial buffer materials or break the shell to absorb energy and achieve water entry load reduction for cross-medium vehicles.

[0027] However, relying solely on the structural strength of a rigid outer shell to resist water entry impact loads is insufficient to effectively reduce overload transmission. This can transfer severe high-frequency loads to internal components of the transmedium vehicle, causing damage or malfunction. While elastic buffer structures may exhibit load reduction at specific entry velocities, when the entry velocity of the transmedium vehicle varies significantly, the original stiffness ratio of the elastic buffer structure may cause the system comprised of the transmedium vehicle and the elastic buffer structure to enter an overload zone. In other words, the load reduction effect of the elastic buffer structure is poor across a wide range of entry velocities. Absorbing energy through sacrificing buffer materials and fracturing the outer shell makes the load reduction structure a single-use structure, unable to be reused to meet the load reduction requirements of transmedium vehicles during round trips or cyclic operations. Furthermore, the debris generated from the fracturing or sacrifice may affect the vehicle's entry attitude and trajectory, resulting in high cleaning and replacement costs.

[0028] To address the problems of the prior art, this application provides a design method for a cross-medium vehicle and a cross-medium vehicle in its embodiments. The design method for the cross-medium vehicle provided in this application embodiment is described below.

[0029] like Figures 1 to 3 As shown, this application provides a design method for a cross-medium vehicle, including the following steps S100 to S700.

[0030] S100. Provide a semi-finished vehicle, which includes a vehicle body 10, a nose cone body 20, and a variable damping component 30. The variable damping component 30 is connected between the vehicle body 10 and the nose cone body 20. The variable damping component 30 includes a piston cylinder 31 and a piston plate 32 movably disposed in the piston cylinder 31 along a first direction X. The piston cylinder 31 is used to contain variable damping fluid 33. One of the piston plate 32 and the piston cylinder 31 is connected to the vehicle body 10, and the other is connected to the nose cone body 20.

[0031] The helmet body 20 is the component that directly bears the hydrodynamic impact when the aircraft hits the water surface. Its material and shape can be customized and replaced according to different water entry speeds and / or water entry angles.

[0032] The variable damping fluid 33 has the rheological properties of a non-Newtonian fluid. The variable damping fluid 33 can be a shear thickening fluid or a shear thinning fluid, depending on the rheological parameters obtained in step S400.

[0033] The piston plate 32 is movably disposed in the piston cylinder 31 along the first direction X, so as to form a gap between the piston plate 32 and the cavity wall of the piston cylinder 31 for supplying the variable damping fluid 33. When the piston plate 32 moves relative to the piston cylinder 31 along the first direction X, the piston plate 32 interacts with the variable damping fluid 33, and the viscosity of the variable damping fluid 33 can passively respond to the change in the movement speed of the piston plate 32 relative to the piston cylinder 31.

[0034] If the variable damping fluid 33 is a shear-thickening fluid, when the speed of the piston plate 32 relative to the piston cylinder 31 increases, the viscosity of the variable damping fluid 33 increases nonlinearly and transiently. The faster the speed, the stronger the variable damping force provided by the variable damping fluid 33. The displacement of the piston plate 32 relative to the piston cylinder 31 is significantly suppressed. The kinetic energy of the piston plate 32 is mainly converted into the heat energy generated by the violent collision and friction between the suspended particles inside the variable damping fluid 33, thus achieving short-stroke, high-dissipation impact buffering.

[0035] If the variable damping fluid 33 is a shear-thinning fluid, when the movement speed of the piston plate 32 relative to the piston cylinder 31 increases, the viscosity of the variable damping fluid 33 decreases. The faster the movement speed, the stronger the fluidity of the variable damping fluid 33, and the smaller the variable damping force provided. The piston plate 32 can generate a large displacement relative to the piston cylinder 31. Part of the kinetic energy of the piston plate 32 is converted into the dissipation of viscous shear heat energy inside the variable damping fluid 33, and the other part is converted into the flow kinetic energy of the variable damping fluid 33 and the pressure potential energy that pushes the variable damping fluid 33, which can realize flexible absorption of impact load.

[0036] When the semi-finished vehicle impacts the water surface, the head cap body 20 first bears the impact and forces the piston plate 32 to move in the piston cylinder 31 along the first direction X.

[0037] If the water entry speed of the semi-finished vehicle changes, it will change the movement speed of the piston plate 32 relative to the piston cylinder 31. The viscosity of the variable damping fluid 33 passively responds to the change in the movement speed of the piston plate 32 relative to the piston cylinder 31, thereby improving the load reduction effect of the variable damping component 30 in a wide speed range, without the need for a complex electronic control system.

[0038] Furthermore, the shearing motion between the piston plate 32 and the variable damping fluid 33 can also convert the impact kinetic energy of the water into heat energy dissipation, introducing a dissipation path for the impact energy.

[0039] S200, obtain the expected cross-medium conditions and preset deceleration criteria.

[0040] The expected cross-medium conditions include at least one of the vehicle's entry angle, entry velocity, and density of the medium 50 to be crossed.

[0041] The preset load reduction standard can be selected according to design requirements. The preset load reduction standard may include reducing the peak value of the impact load on the vehicle body 10 during the water entry process. The preset load reduction standard may also include reducing the impact pulsation frequency on the vehicle body 10 during the water entry process.

[0042] S300, set the rheological parameters of the variable damping fluid 33 contained in the piston cylinder 31 as the terms to be solved, and obtain the load model of the impact load on the vehicle body 10 as a function of time under the expected cross-medium conditions.

[0043] S400. Under the condition that the load model meets the preset load reduction criteria, solve for the rheological parameters.

[0044] In step S300, the rheological parameters of the variable damping fluid 33 are set as unknowns to be solved, and a load model is obtained showing the time-varying impact load on the vehicle body 10 under expected transmedium conditions. The load model includes the rheological parameters of the variable damping fluid 33. In step S400, under the condition that the load model meets the preset load reduction criteria, an inverse solution operation is performed based on the load model to obtain the rheological parameters of the variable damping fluid 33.

[0045] S500, Obtain the variable damping fluid 33 based on the rheological parameters.

[0046] The variable damping fluid obtained in step S500 can ensure that the load model of the impact load on the vehicle body 10 changes with time under the expected cross-medium conditions, which meets the preset load reduction standard.

[0047] Step S500 can select the finished variable damping fluid 33 according to the rheological parameters, or step S500 can prepare the variable damping fluid 33 according to the rheological parameters.

[0048] S600, inject the variable damping fluid 33 into the piston cylinder 31, and connect the elastic reset member 40 between the vehicle body 10 and the head cap body 20 to obtain the vehicle assembly 1.

[0049] With the aid of the elastic reset member 40 connected between the vehicle body 10 and the nose cone body 20, when the vehicle assembly 1 impacts the water surface, under the action of the impact load, the nose cone body 20 and the piston plate 32 gain impact kinetic energy and move relative to the piston cylinder 31 in the first direction X and close to the vehicle body 10. This compresses the elastic reset member 40 while simultaneously squeezing the variable damping fluid 33 inside the piston cylinder 31. Due to elastic deformation, the elastic reset member 40 converts a portion of the impact kinetic energy into elastic potential energy for storage. The variable damping fluid 33 interacts with the piston plate 32, generating a variable damping force opposite to the relative velocity of the piston plate 32. This variable damping force is related to the relative velocity of the piston plate 32 relative to the piston cylinder 31, converting another portion of the impact kinetic energy into the shear internal energy of the variable damping fluid 33 and dissipating it as heat. As the piston... The piston plate 32 moves continuously relative to the piston cylinder 31, and the kinetic energy of the cap body 20 and the piston plate 32 is continuously converted into elastic potential energy and shear internal energy until the relative velocity of the piston plate 32 relative to the piston cylinder 31 is zero. At this time, the elastic potential energy stored in the elastic reset member 40 reaches its peak value. The elastic reset member 40 releases its stored elastic potential energy, pushing the cap body 20 and the piston plate 32 to move relative to the piston cylinder 31 in the first direction X and away from the vehicle body 10. Under the action of the reset force of the elastic reset member, the cap body 20 and the piston plate 32 gradually return to their original positions. During the return process, the variable damping fluid 33 continues to provide variable damping force until the cap body 20 and the piston plate 32 return to their initial positions before being subjected to the impact load. The residual energy is completely dissipated, realizing the cross-medium shape restoration of the vehicle assembly 1 and supporting reuse.

[0050] If the variable damping fluid 33 is a shear-thickening fluid, at the moment the vehicle assembly 1 impacts the water surface, the head cap body 20 and the piston plate 32 gain impact kinetic energy. The relative velocity of the piston plate 32 relative to the piston cylinder 31 reaches the peak value during the impact process. The variable damping fluid 33 is subjected to severe shearing action by the piston plate 32 and undergoes shear thickening effect. The variable damping fluid 33 generates a variable damping force that is nonlinearly positively correlated with the relative velocity, so that the variable damping fluid 33 provides strong damping in the peak impact stage. The displacement of the piston plate 32 relative to the piston cylinder 31 is significantly suppressed, effectively suppressing the mechanical load phenomenon caused by resonance or hysteresis effect of the elastic reset component 40 in a specific frequency domain, and avoiding secondary amplification of impact load.

[0051] Furthermore, by converting some of the impact kinetic energy into elastic potential energy for temporary storage, and combined with the characteristic that the variable damping force of the variable damping fluid 33 gradually decreases as the relative velocity decreases, the impact kinetic energy temporarily stored as elastic potential energy is slowly released and dissipated by the variable damping fluid 33, so that the interaction force between the piston plate 32 and the piston cylinder 31 changes from a sharp pulse shape to a smooth waveform with reduced amplitude and extended duration.

[0052] If the variable damping fluid 33 is a shear-thinning fluid, the piston plate 32 can generate a large displacement relative to the piston cylinder 31, and more impact kinetic energy can be converted into elastic potential energy for temporary storage, making the deceleration process of the piston plate 32 smoother and prolonging the impact time.

[0053] S700. Under the expected cross-medium conditions, conduct a cross-medium test on the aircraft assembly 1 to obtain test data on the change of impact load on the aircraft body 10 over time, determine whether the test data meets the preset load reduction standard, and replace the elastic reset component 40 with different damping performance according to the judgment result until the test data meets the preset load reduction standard.

[0054] After the introduction of the elastic reset element 40, the variable damping fluid 33 and the elastic reset element 40 are coupled together. Under the premise that the variable damping fluid 33 is fixed, if the damping performance of the elastic reset element 40 is too low, the elastic reset element 40 will rebound rapidly after the impact, causing the piston plate 32 to oscillate violently relative to the piston cylinder 31 or to transmit the impact secondaryly, and thus failing to effectively absorb and dissipate energy. If the damping performance of the elastic reset element 40 is too high, the response lag of the elastic reset element 40 will be severe, which will suppress the transient hardening characteristics of the variable damping fluid 33 under high-speed impact (for shear thickening fluids) or prevent it from utilizing its flow drag reduction advantage (for shear thinning fluids), thereby weakening the buffering and isolation effect on the impact load.

[0055] In step S700, experiments are conducted by replacing the elastic reset member 40 with different damping properties. In steps S300 to S500, rheological parameters are calculated and solved, and the variable damping fluid 33 is obtained based on the solved rheological parameters. This is because the design method of the cross-medium vehicle provided in this embodiment has a cost advantage compared to conducting experiments by replacing the variable damping fluid 33 with different rheological parameters.

[0056] By applying the design method of the cross-medium vehicle provided in this embodiment, the damping performance of the elastic reset member 40 and the rheological parameters of the variable damping fluid 33 are adjusted to adapt to the set expected cross-medium conditions and preset load reduction standards. This allows the cross-medium vehicle obtained through the design method to, upon entering the water, gain impact kinetic energy under impact load. The head cap body 20 and piston plate 32 then move relative to the piston cylinder 31 along the first direction X, close to the vehicle body 10. This compresses the elastic reset member 40 and simultaneously squeezes the variable damping fluid 33 within the piston cylinder 31. The viscosity of the variable damping fluid 33 passively responds to changes in the velocity of the piston plate 32 relative to the piston cylinder 31, enabling cross-medium navigation. The device can adapt to different water entry velocities for load reduction. The impact kinetic energy can be converted into the internal energy of the variable damping fluid 33 for dissipation, and can also be converted into the elastic potential energy of the elastic reset member 40 for temporary storage. Until the relative velocity of the piston plate 32 with respect to the piston cylinder 31 is zero, the elastic reset member 40 releases its stored elastic potential energy, pushing the head cap body 20 and the piston plate 32 to move relative to the piston cylinder 31 in the first direction X, away from the vehicle body 10. Under the reset force of the elastic reset member, the head cap body 20 and the piston plate 32 gradually return to their original positions. During the return process, the variable damping fluid 33 continues to provide variable damping force until the head cap body 20 and the piston plate 32 return to their initial positions before being subjected to the impact load, and the residual energy is completely dissipated. Therefore, the cross-medium vehicle obtained through the design method of cross-medium vehicle can adapt to different water entry velocities for load reduction and can meet the water entry and load reduction requirements of cross-medium vehicle in multiple cross-medium processes.

[0057] like Figure 4 As shown, in some embodiments, step S300 includes the following steps S310 to S340.

[0058] S310. Set the rheological parameters of the variable damping fluid 33 contained in the piston cylinder 31 as the terms to be solved, and obtain the variable damping mechanical model with rheological parameters. The variable damping mechanical model is used to calculate the damping force F applied by the variable damping fluid 33 contained in the piston cylinder 31 to the vehicle body 10 and the nose cone body 20 through the variable damping component 30. c .

[0059] In step S310, the rheological parameters of the variable damping fluid 33 contained in the piston cylinder 31 are set as unknowns to be solved. Based on the variable damping mechanical model, the damping force F applied by the variable damping component 30 to the vehicle body 10 and the nose cone body 20 is calculated when the rheological parameters of the variable damping fluid 33 in the piston cylinder 31 are unknown. c Damping force F c The size is related to the relative velocity of piston plate 32 with respect to piston cylinder 31, and the damping force F. c It has rheological parameters to be solved.

[0060] S320. Under expected cross-medium conditions, determine the expected impact force F on the head cap body 20 of the semi-finished vehicle.

[0061] In step S320, the expected impact force F is the water impact force borne by the head cap body 20 when the semi-finished vehicle impacts the water surface under the expected cross-medium conditions. The expected impact force F varies with the expected cross-medium conditions.

[0062] S330. Under the expected cross-medium conditions, perform a force analysis on the semi-finished vehicle to obtain the force equations for the head cap body 20 and the vehicle body 10.

[0063] like Figure 5 As shown, a force analysis of the semi-finished vehicle under expected transmedium conditions is performed. The semi-finished vehicle impacts the water surface under expected transmedium conditions. The nose cone body 20 is subjected to the impact of water entry, which forces the piston plate 32 to move in the piston cylinder 31 along the first direction X. The piston plate 32 interacts with the variable damping fluid 33. The variable damping fluid 33 applies a first damping force F1 along the first direction from the vehicle body 10 to the nose cone body 20 through the piston plate 32. At the same time, the variable damping fluid 33 applies a second damping force F2 along the first direction from the nose cone body 20 to the vehicle body 10 through the piston cylinder 31. The first damping force F1 and the second damping force F2 are equal in magnitude but opposite in direction. In the force equations of the helmet body 20 and the vehicle body 10, along the first direction, the helmet body 20 and the piston plate 32 are subjected to the expected impact force F from the helmet body 20 to the vehicle body 10 and the first damping force F1 from the vehicle body 10 to the helmet body 20. The resultant force of the expected impact force F and the first damping force F1 determines the acceleration of the helmet body 20 and the piston plate 32. The piston cylinder 31 and the vehicle body 10 are subjected to the second damping force F2 from the helmet body 20 to the vehicle body 10. The second damping force F2 determines the acceleration of the piston cylinder 31 and the vehicle body 10.

[0064] S340. Substitute the variable damping mechanical model and the expected impact force F into the force equations to obtain the load model of the impact load on the vehicle body 10 as a function of time.

[0065] It should be noted that the load model of the impact load on the vehicle body 10 over time refers to the data of the acceleration of the vehicle body 10 over time.

[0066] Substituting the variable damping mechanical model with unsolved rheological parameters obtained in step S310 and the expected impact force F obtained in step S320 into the force equation set obtained in step S330, the first damping force F1 and the second damping force F2 are both equal to the variable damping mechanical model. According to the force equation set, the resultant force of the expected impact force F and the first damping force F1 determines the acceleration of the head cap body 20 and the piston plate 32, and the second damping force F2 determines the acceleration of the piston cylinder 31 and the vehicle body 10. Since the variable damping mechanical model has unsolved rheological parameters and the variable damping mechanical model is related to the relative velocity of the piston cylinder 31 and the piston plate 32, the acceleration of the vehicle body 10 has unsolved rheological parameters and changes with time.

[0067] like Figure 5 and Figure 6 As shown, in some embodiments, the expected transmedium conditions include the expected velocity V and the medium density, and step S320 includes the following steps S321 and S322.

[0068] S321. Obtain the impact force model, which is used to calculate the expected impact force F.

[0069] The impact force model is used to calculate the water impact force experienced by the head cap body 20 when the semi-finished vehicle impacts the water surface under the expected cross-medium conditions, given that the expected cross-medium conditions are determined. The impact force model contains several variables determined according to the expected cross-medium conditions.

[0070] S322. Obtain the structural data of the headgear body 20, determine the force-bearing area variable of the impact force model based on the structural data, determine the velocity variable of the impact force model based on the expected velocity V, and determine the density variable of the impact force model based on the medium density.

[0071] When the semi-finished vehicle impacts the water surface under the expected cross-medium conditions, the water impact force borne by the head cap body 20 is related to its impact velocity, the area of ​​impact, and the density of the medium 50 to be entered. Therefore, the impact force model includes variables of the area of ​​impact, velocity, and density.

[0072] The expected cross-medium conditions include the expected velocity and the medium density. The medium density refers to the density of the medium to be crossed, and the expected velocity refers to the velocity at which the semi-finished vehicle impacts the water surface under the expected cross-medium conditions.

[0073] Based on the structural data of the helmet body 20, the force area variable of the helmet body 20 under the impact of the medium 50 to be entered when the semi-finished vehicle impacts the water surface under the expected cross-medium conditions is determined.

[0074] The impact force model is both a fixed formula and a calculation tool that can be adjusted according to the expected changes in cross-medium conditions. It helps engineers assess the expected impact force F on the head cap body 20 when the semi-finished vehicle impacts the water surface under the expected cross-medium conditions during the design phase.

[0075] In some embodiments, the anticipated cross-medium condition further includes a cross-medium angle, and the structural data includes the outer contour shape information and bottom area of ​​the headgear body 20. The step of determining the force area variable of the impact force model based on the structural data includes: determining the force angle variable of the force area variable based on the cross-medium angle, determining the headgear shape coefficient of the force area variable based on the outer contour shape information, and determining the base area variable of the force area variable based on the bottom area.

[0076] The force-bearing area of ​​the helmet body 20 that is subjected to the impact of the medium 50 to be entered is related to the shape of the helmet body 20 and the water entry angle of the semi-finished vehicle. Therefore, the force-bearing area variable includes the force angle variable, the helmet shape coefficient and the base area variable.

[0077] The expected cross-medium conditions also include the cross-medium angle, which refers to the water entry angle at which the semi-finished vehicle impacts the water surface under the expected cross-medium conditions, that is, the angle between the normal of the bottom surface 21 of the head cap body 20 and the liquid surface of the medium 50 to be crossed.

[0078] The structural data includes the outer contour shape information and bottom area of ​​the headgear body 20. The headgear body 20 has a bottom surface 21 facing the vehicle body 10 and other surfaces. The bottom area refers to the area of ​​the bottom surface 21, and the outer contour shape information refers to the shape formed by the other surfaces, such as a cone, cylinder or bullet shape.

[0079] In some examples, the expected impact force, expected velocity, medium density, transmedium angle, headgear shape factor, and base area must satisfy formula (1): (1) Where F is the expected impact force, ρ is the medium density, α is the cross-medium angle, A is the base area, C is the headgear shape factor, and V is the expected velocity.

[0080] In some embodiments, the preset load reduction criteria include a preset peak load upper limit and a preset load change frequency upper limit. The step of replacing the elastic reset element 40 with different damping performance according to the judgment result includes: S710. If the judgment result shows that the peak load of the test data is greater than the preset peak load upper limit, then reduce the damping performance of the elastic reset member 40.

[0081] After the introduction of the elastic reset component 40, the variable damping fluid 33 and the elastic reset component 40 are coupled to each other. Under the premise that the variable damping fluid 33 is determined, if the judgment result shows that the load peak value of the test data is greater than the preset load peak value upper limit, it indicates that the damping performance of the elastic reset component 40 is too high and the response lag of the elastic reset component 40 is serious, which inhibits the transient hardening characteristics that the variable damping fluid 33 should have under high-speed impact (for shear thickening fluids) or cannot utilize its flow drag reduction advantage (for shear thinning fluids). Therefore, it is necessary to reduce the damping performance of the elastic reset component 40.

[0082] S720. If the judgment result shows that the frequency of load change with time in the test data is greater than the preset upper limit of load change frequency, then increase the damping performance of the elastic reset member 40.

[0083] After the introduction of the elastic reset component 40, the variable damping fluid 33 and the elastic reset component 40 are coupled to each other. Under the premise that the variable damping fluid 33 is determined, if the judgment result shows that the frequency of load change with time in the test data is greater than the upper limit of the preset load change frequency, it indicates that the damping performance of the elastic reset component 40 is too low. The elastic reset component 40 rebounds rapidly after the impact, causing the piston plate 32 to oscillate violently relative to the piston cylinder 31 or to transmit the impact twice. It cannot effectively absorb and dissipate energy, so it is necessary to increase the damping performance of the elastic reset component 40.

[0084] like Figure 7 and Figure 8 As shown, in some embodiments, step S500 includes the following steps S510 to S530.

[0085] S510, Preparation of variable damping fluid 33.

[0086] In some examples, step S510 uses deionized water or pure water as the base liquid and slowly adds organic microparticles (such as starch microparticles or composite colloidal suspensions) as the dispersed phase in a specific mass fraction range to prepare variable damping fluid 33.

[0087] S520. Perform rheological tests on the variable damping fluid 33 to determine whether the variable damping fluid 33 meets the rheological parameters.

[0088] S530. If the variable damping fluid 33 does not meet the rheological parameters, adjust the component ratio of the variable damping fluid 33 and re-prepare it until the variable damping fluid 33 meets the rheological parameters.

[0089] In some examples, if the variable damping fluid 33 does not meet the rheological parameters, step S530 can adjust the component ratio of the variable damping fluid 33 by changing the mass fraction of the dispersed phase or the particle gradation, thereby controlling and obtaining variable damping fluid 33 with different rheological parameters.

[0090] In some embodiments, the preset load reduction criteria include a preset peak load limit and a preset load change frequency limit, and the rheological parameters include the viscosity coefficient and the velocity index.

[0091] The preset load reduction standard includes a preset peak load upper limit and a preset load change frequency upper limit. The preset load reduction standard of the cross-medium vehicle obtained through the design method of the cross-medium vehicle means that during the process of the cross-medium vehicle entering the water, the peak value of the impact load on the vehicle body 10 is less than or equal to the preset peak load upper limit, and the frequency of the impact load on the vehicle body 10 fluctuating with time is less than or equal to the preset load change frequency upper limit, so as to achieve the predictability and verifiability of the protection performance.

[0092] The viscosity coefficient reflects the overall consistency of the variable damping fluid 33. When the piston plate 32 moves at the same speed relative to the piston cylinder 31, the larger the viscosity coefficient, the greater the damping force generated by the variable damping fluid 33 on the movement of the piston plate 32 relative to the piston cylinder 31.

[0093] The velocity index characterizes the sensitivity of the viscosity of the variable damping fluid 33 to the movement speed of the piston plate 32 relative to the piston cylinder 31. For example, when the velocity index is less than 1, the variable damping fluid 33 is a shear-thinning fluid, and the viscosity of the variable damping fluid 33 decreases as the movement speed of the piston plate 32 relative to the piston cylinder 31 increases; when the velocity index is greater than 1, the variable damping fluid 33 is a shear-thickening fluid, and the viscosity of the variable damping fluid 33 increases as the movement speed of the piston plate 32 relative to the piston cylinder 31 increases.

[0094] By measuring the viscosity coefficient and velocity index, the damping characteristics of the variable damping fluid 33 under different expected transmedium conditions can be predicted and optimized.

[0095] In some embodiments, the elastic reset member 40 includes a mechanical spring, and the step of replacing the elastic reset member 40 with a different damping performance according to the judgment result includes: replacing the mechanical spring with a different elastic coefficient according to the judgment result.

[0096] Mechanical springs rely on the elastic deformation of metallic materials to store and release energy. Their restoring force is basically linearly related to the amount of deformation, and they have the advantages of simple structure, rapid response, long life and high energy density. For example, mechanical springs include nickel-titanium alloy springs.

[0097] In some embodiments, the elastic reset member 40 includes a gas spring, and the step of replacing the elastic reset member 40 with a different damping performance according to the judgment result includes: replacing the gas spring with a different initial gas pressure according to the judgment result.

[0098] Gas springs utilize the compressibility of enclosed gas to store energy. In the initial stage of compression, gas springs release heat and have low stiffness. As the compression increases, the stiffness increases. The initial stiffness and preload can be changed by adjusting the initial gas pressure.

[0099] In some embodiments, the variable damping member 30 further includes a piston rod 34, which is connected between the head cap body 20 and the piston plate 32. The piston rod 34 is movably inserted through the piston cylinder 31 along the first direction X. A sliding pair is formed between the piston rod 34 and the piston cylinder 31 to generate frictional damping, which serves as another energy dissipation path for the impact kinetic energy of the vehicle entering the water. After step S700, the preload of the sliding pair between the piston rod 34 and the piston cylinder 31 can be adjusted.

[0100] like Figure 2 as well as Figures 9 to 13 As shown, another embodiment of this application provides a cross-medium vehicle, which is obtained by the design method of the cross-medium vehicle provided above. The cross-medium vehicle includes a vehicle body 10, a helmet body 20, a variable damping element 30, and an elastic reset element 40. The helmet body 20 is movably disposed on one side of the vehicle body 10 along a first direction X. The variable damping element 30 is located and connected between the vehicle body 10 and the helmet body 20 along the first direction X. The variable damping element 30 includes a piston cylinder 31 and a piston plate 32. The piston cylinder 31 is used to contain variable damping fluid 33. The piston plate 32 is movably disposed in the piston cylinder 31 along the first direction X. One of the piston plate 32 and the piston cylinder 31 is connected to the vehicle body 10, and the other is connected to the helmet body 20. The elastic reset element 40 is located and connected between the vehicle body 10 and the helmet body 20 along the first direction X to apply a reset force away from the vehicle body 10 along the first direction X to the helmet body 20.

[0101] The cross-medium vehicle provided in this embodiment is obtained by the design method described above. The cross-medium vehicle includes a vehicle body 10, a nose cone body 20, a variable damping element 30, and an elastic reset element 40. By adjusting the damping performance of the elastic reset element 40 and the rheological parameters of the variable damping fluid 33, it adapts to the set expected cross-medium conditions and preset load reduction standards. When the cross-medium vehicle, obtained through the design method, enters the water, under impact load, the nose cone body 20 and piston plate 32 gain impact kinetic energy, moving relative to the piston cylinder 31 along the first direction X, close to the vehicle body 10. This compresses the elastic reset element 40 while simultaneously squeezing the variable damping fluid 33 within the piston cylinder 31. The viscosity of the variable damping fluid 33 is passively adjusted. The change in the velocity of the piston plate 32 relative to the piston cylinder 31 allows the cross-medium vehicle to adapt to different water entry velocities for load reduction. The impact kinetic energy can be converted into the internal energy of the variable damping fluid 33 for dissipation, and also into the elastic potential energy of the elastic reset member 40 for temporary storage. This continues until the relative velocity of the piston plate 32 relative to the piston cylinder 31 reaches zero. The elastic reset member 40 then releases its stored elastic potential energy, pushing the head cap body 20 and the piston plate 32 along the first direction X, away from the vehicle body 10, relative to the piston cylinder 31. Under the reset force of the elastic reset member, the head cap body 20 and the piston plate 32 gradually return to their original positions. During this return process, the variable damping fluid 33 continues to provide variable damping force until the head cap body 20 and the piston plate 32 return to their initial positions before the impact load, and the residual energy is completely dissipated. Therefore, the cross-medium vehicle designed using this method can adapt to different water entry velocities for load reduction and can meet the water entry and load reduction requirements of cross-medium vehicles in multiple cross-medium processes.

[0102] like Figure 2 and Figure 12 As shown, in some embodiments, the piston cylinder 31 includes an adapter 311 and a piston cover 312. The adapter 311 is connected to the vehicle body 10, and the piston cover 312 is disposed on the side of the adapter 311 away from the vehicle body 10. The piston cover 312 is connected to the adapter 311 and surrounds the piston cylinder 31.

[0103] In some optional embodiments of this application, the transition section is used to connect the vehicle body 10 and the piston cover 312, and together with the piston cover 312, forms a chamber for accommodating the variable damping fluid 33.

[0104] In some examples, the transition section includes a first threaded section 3112 and a second threaded section 3113 connected along a first direction X. Both the first threaded section 3112 and the second threaded section 3113 have external threads. The first threaded section 3112 extends into the piston cover 312 and is threadedly connected to the piston cover 312. The second threaded section 3113 extends into the vehicle body 10 and is threadedly connected to the vehicle body 10, thereby improving the coaxiality and reliability of the assembly of the piston cylinder 31 and the vehicle body 10.

[0105] like Figure 2 , Figure 9 as well as Figure 10 As shown, in some embodiments, the variable damping element 30 further includes a piston rod 34 and a first sealed bearing 35. The piston rod 34 is connected between the head cap body 20 and the piston plate 32. The first sealed bearing 35 is sleeved on the piston rod 34. The inner ring of the first sealed bearing 35 is connected to the piston rod 34, and the outer ring of the first sealed bearing 35 is connected to the piston cover 312.

[0106] In some optional embodiments of this application, the first sealing bearing 35 can guide the movement of the piston rod 34 along the first direction X, which helps the piston rod 34 to move smoothly, avoids off-center loading and jamming, and improves the sealing effect of the chamber containing the variable damping fluid 33.

[0107] like Figure 2 As shown, in some embodiments, the adapter 311 has a mounting groove 3111 coaxially disposed with the piston rod 34. One end of the piston rod 34 away from the head cap body 20 along the first direction X can extend into the mounting groove 3111 along the first direction X. The elastic reset member 40 is disposed in the mounting groove 3111 and is connected to the piston rod 34 and the adapter 311 respectively.

[0108] In some optional embodiments of this application, the mounting groove 3111 provides a stable mounting space for the elastic reset member 40. The groove wall of the mounting groove 3111 can limit the deformation direction of the elastic reset member 40, which helps the reset force provided by the elastic reset member 40 to act on the piston rod 34 along the first direction X. The groove wall of the mounting groove 3111 can also be used to guide the movement direction of the piston rod 34 relative to the piston cylinder 31.

[0109] like Figure 2 As shown, in some embodiments, the variable damping member 30 further includes a second sealed bearing 36, which is sleeved on the piston rod 34. The inner ring of the second sealed bearing 36 is connected to the piston rod 34, and the outer ring of the second sealed bearing 36 is connected to the adapter 311.

[0110] In some optional embodiments of this application, the second sealing bearing 36 can guide the movement of the piston rod 34 along the first direction X, which helps the piston rod 34 to move smoothly, avoids off-center loading and jamming, and improves the sealing effect of the chamber containing the variable damping fluid 33.

[0111] like Figure 11 As shown, in some embodiments, the piston plate 32 has at least one through hole 321 disposed along the first direction X.

[0112] In some optional embodiments of this application, when the piston plate 32 moves relative to the piston cylinder 31 along the first direction X, the variable damping fluid 33 located on both sides of the piston plate 32 in the first direction X is connected through the through hole 321, and the variable damping fluid 33 can flow on both sides of the piston plate 32 through the through hole 321.

[0113] The number, size, and distribution of through holes 321 can be designed as needed.

[0114] The structure of the piston plate 32 can be designed as a conical or flat plate as needed.

[0115] In some embodiments, at least one piston plate 32 is provided on the piston rod 34 and distributed along the first direction X.

[0116] The piston rod 34 has a threaded section 341, and the piston plate 32 is sleeved on the threaded section 341 and threadedly connected to the threaded section 341.

[0117] In some embodiments, the resilient reset member 40 includes at least one of a mechanical spring and a gas spring.

[0118] Mechanical springs rely on the elastic deformation of metallic materials to store and release energy. Their restoring force is basically linearly related to the amount of deformation. They have the advantages of simple structure, rapid response, long life and high energy density.

[0119] Gas springs utilize the compressibility of enclosed gas to store energy. In the initial stage of compression, gas springs release heat and have low stiffness. As the compression increases, the stiffness increases. The initial stiffness and preload can be changed by adjusting the initial gas pressure.

[0120] Using the cross-medium vehicle provided in this embodiment, the variable damping element 30 and the elastic reset element 40 can be connected in series between the vehicle body 10 and the helmet body 20, or the variable damping element 30 and the elastic reset element 40 can be connected in parallel between the vehicle body 10 and the helmet body 20.

[0121] like Figure 2 As shown, in some embodiments, the variable damping element 30 and the elastic reset element 40 are connected in series between the vehicle body 10 and the helmet body 20.

[0122] The variable damping element 30 and the elastic reset element 40 are distributed sequentially along the first direction X. One of the piston plate 32 and the piston cylinder 31 is connected to one end of the elastic reset element 40 along the first direction X. The other of the piston plate 32 and the piston cylinder 31 is connected to one of the vehicle body 10 and the helmet body 20. The other end of the elastic reset element 40 along the first direction X is connected to the other of the vehicle body 10 and the helmet body 20.

[0123] In some optional embodiments of this application, the variable damping element 30 and the elastic reset element 40 are connected in series between the vehicle body 10 and the helmet body 20, which helps to save structural dimensions along the first direction X.

[0124] In some examples, the variable damping element 30 and the elastic reset element 40 are arranged coaxially.

[0125] like Figure 13 As shown, in some other embodiments, the variable damping element 30 and the elastic reset element 40 are connected in parallel between the piston cylinder 31 and the head cap body 20.

[0126] That is, one of the piston plate 32 and the piston cylinder 31 is connected to the vehicle body 10, and the other is connected to the head cap body 20. The elastic reset member 40 is connected to the vehicle body 10 at one end along the first direction X, and to the head cap body 20 at the other end.

[0127] In some embodiments, the variable damping element 30 and the elastic reset element 40 are both detachably connected to the headgear body 20.

[0128] In some optional embodiments of this application, the variable damping element 30 and the elastic reset element 40 are both detachably connected to the head cap body 20, so as to replace different models of the head cap body 20 according to different water entry speeds and / or water entry angles.

[0129] The material and shape of the headgear body 20 can be customized according to different water entry speeds and / or water entry angles.

[0130] In some embodiments, the variable damping element 30 and the elastic reset element 40 are both detachably connected to the vehicle body 10.

[0131] In some optional embodiments of this application, when the vehicle body 10 needs to be repaired or replaced, only the vehicle body 10 needs to be disassembled, reducing maintenance costs and time.

[0132] It should be noted that the cross-medium vehicle provided in this application has the beneficial effects of the design method of the cross-medium vehicle in any of the foregoing embodiments. For details, please refer to the foregoing description of the beneficial effects of the design method of the cross-medium vehicle. This application will not repeat the description.

[0133] While the embodiments disclosed in this application are as described above, the content is merely for the purpose of facilitating understanding of this application and is not intended to limit the invention. Any person skilled in the art to which this application pertains may make any modifications and changes in form and detail of the implementation without departing from the spirit and scope disclosed in this application; however, the scope of protection of this application shall still be determined by the scope defined in the appended claims.

[0134] The above description is merely a specific embodiment of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, substitutions for other connection methods described above can be made by referring to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application.

Claims

1. A design method for a cross-medium vehicle, characterized in that, include: A semi-finished vehicle is provided, comprising a vehicle body, a nose cone body, and a variable damping component. The variable damping component is connected between the vehicle body and the nose cone body. The variable damping component includes a piston cylinder and a piston plate movably disposed in the piston cylinder along a first direction. The piston cylinder is used to contain variable damping fluid. One of the piston plate and the piston cylinder is connected to the vehicle body, and the other is connected to the nose cone body. Obtain the expected cross-medium conditions and preset load reduction criteria; The rheological parameters of the variable damping fluid contained in the piston cylinder are set as the terms to be solved. Under the expected transmedium conditions, the load model of the impact load on the vehicle body as a function of time is obtained. Under the condition that the load model meets the preset load reduction criteria, the rheological parameters are solved; The variable damping fluid is obtained based on the rheological parameters; The variable damping fluid is injected into the piston cylinder, and the elastic reset member is connected between the vehicle body and the head cap body to obtain the vehicle assembly. Under the expected cross-medium conditions, the aircraft assembly is subjected to a cross-medium test to obtain test data on the impact load on the aircraft body over time. It is then determined whether the test data meets the preset load reduction standard. Based on the determination result, the elastic reset component with different damping performance is replaced until the test data meets the preset load reduction standard.

2. The design method for a cross-medium vehicle according to claim 1, characterized in that, The steps of setting the rheological parameters of the variable damping fluid contained in the piston cylinder as the terms to be solved, and obtaining the load model of the impact load on the vehicle body as a function of time under the expected transmedium conditions, include: The rheological parameters of the variable damping fluid contained in the piston cylinder are set as the terms to be solved, and a variable damping mechanical model with the rheological parameters is obtained. The variable damping mechanical model is used to calculate the damping force applied by the variable damping fluid contained in the piston cylinder to the vehicle body and the head cap body through the variable damping component. Under the expected cross-medium conditions, determine the expected impact force on the headgear body of the semi-finished vehicle. Under the expected cross-medium conditions, the semi-finished vehicle was subjected to a stress analysis to obtain the set of force equations for the headgear body and the vehicle body. Substituting the variable damping mechanical model and the expected impact force into the force equations, a load model showing the time-varying impact load on the vehicle body is obtained.

3. The design method for a cross-medium vehicle according to claim 2, characterized in that, The expected cross-medium conditions include expected velocity and medium density. Under these conditions, the steps for determining the expected impact force on the hood body of the semi-finished vehicle include: Obtain an impact force model, which is used to calculate the expected impact force; Obtain the structural data of the headgear body, determine the force-bearing area variable of the impact force model based on the structural data, determine the velocity variable of the impact force model based on the expected velocity, and determine the density variable of the impact force model based on the medium density.

4. The design method for a cross-medium vehicle according to claim 3, characterized in that, The expected cross-medium condition also includes a cross-medium angle, and the structural data includes the outer contour shape information and bottom area of ​​the headgear body. The step of determining the force area variable of the impact force model based on the structural data includes: The force angle variable of the force area variable is determined based on the cross-medium angle, the head cap shape coefficient of the force area variable is determined based on the outer contour shape information, and the base area variable of the force area variable is determined based on the bottom area.

5. The design method for a cross-medium vehicle according to claim 1, characterized in that, The preset load reduction criteria include a preset peak load upper limit and a preset load change frequency upper limit. The step of replacing the elastic reset component with different damping performance based on the judgment result includes: If the judgment result shows that the peak load of the test data is greater than the preset peak load upper limit, then the damping performance of the elastic reset member is reduced; If the judgment result shows that the frequency of load change over time in the test data is greater than the preset upper limit of load change frequency, then the damping performance of the elastic reset component is increased.

6. The design method for a cross-medium vehicle according to claim 1, characterized in that, The step of obtaining the variable damping fluid based on the rheological parameters includes: Preparation of variable damping fluid; Rheological tests were performed on the variable damping fluid to determine whether the variable damping fluid met the rheological parameters; If the variable damping fluid does not meet the rheological parameters, the component ratio of the variable damping fluid is adjusted and it is prepared again until the variable damping fluid meets the rheological parameters.

7. The design method for a cross-medium vehicle according to claim 1, characterized in that, The preset load reduction criteria include a preset peak load upper limit and a preset load change frequency upper limit, and the rheological parameters include viscosity coefficient and velocity index.

8. A transmedium-based vehicle, characterized in that, The transmedium vehicle is obtained by the design method of the transmedium vehicle according to any one of claims 1 to 7, and the transmedium vehicle comprises: The vessel itself; The headgear body is movably disposed on one side of the vehicle body along a first direction; A variable damping element is located and connected between the vehicle body and the hood body along the first direction. The variable damping element includes a piston cylinder and a piston plate. The piston cylinder is used to contain variable damping fluid. The piston plate is movably disposed in the piston cylinder along the first direction. One of the piston plate and the piston cylinder is connected to the vehicle body, and the other is connected to the hood body. An elastic reset member is located and connected between the vehicle body and the hood body along the first direction to apply a reset force to the hood body away from the vehicle body along the first direction.

9. The transmedium vehicle according to claim 8, characterized in that, The piston cylinder includes: Adapter, connected to the vehicle body; A piston cover is provided on the side of the adapter opposite to the vehicle body. The piston cover is connected to the adapter and surrounds the piston cylinder.

10. The transmedium vehicle according to claim 9, characterized in that, The variable damping element also includes: A piston rod is connected between the headgear body and the piston plate; A first sealed bearing is sleeved on the piston rod, with its inner ring connected to the piston rod and its outer ring connected to the piston cover.

11. The transmedium vehicle according to claim 10, characterized in that, The adapter has a mounting groove coaxially arranged with the piston rod. One end of the piston rod away from the head cap body along the first direction can extend into the mounting groove along the first direction. The elastic reset member is disposed in the mounting groove and is connected to the piston rod and the adapter.

12. The transmedium vehicle according to claim 11, characterized in that, The variable damping element also includes: A second sealed bearing is sleeved on the piston rod, with its inner ring connected to the piston rod and its outer ring connected to the adapter.

13. The transmedium vehicle according to claim 8, characterized in that, The piston plate has at least one through hole extending along the first direction; and / or, The elastic reset element includes at least one of a mechanical spring and a gas spring.

14. The transmedium vehicle according to claim 8, characterized in that, The variable damping element and the elastic reset element are connected in series between the vehicle body and the helmet body; or... The variable damping element and the elastic reset element are connected in parallel between the vehicle body and the helmet body.

15. The transmedium vehicle according to claim 8, characterized in that, Both the variable damping element and the elastic reset element are detachably connected to the headgear body; and / or Both the variable damping component and the elastic reset component are detachably connected to the vehicle body.

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