Dummy head injury testing device and method for impact test

Abstract

The invention discloses a dummy head injury testing device and method for an impact test, the testing device comprises a head assembly, the head assembly comprises a skull, brain tissue, head skin and a sensing device, eye sockets are arranged on the skull, and bionic eyeballs are arranged at the eye sockets; the brain tissue comprises bionic brain tissue and bionic cerebrospinal fluid; the head skin comprises a head skin body and flexible sensing skin arranged on the outer surface of the head skin body, the flexible sensing skin comprises a flexible substrate layer, wire electrodes arranged on the two end faces of the flexible substrate layer respectively and insulating layers covering the wire electrodes, and a plurality of wire electrodes are arranged on the two end faces at intervals. The wire electrodes on the two end faces are orthogonally arranged to form an array structure, and raw materials of the flexible substrate layer comprise silicone rubber and a conductive material. The testing device is good in biological simulation degree, the testing result is closer to the real situation, multiple sensor configuration schemes are provided, and more head injury data can be obtained.

Description

Technical Field

[0001] This invention relates to the field of human body impact safety protection testing technology, specifically to a dummy head injury testing device and method for impact testing. Background Technology

[0002] Studies show that more than 60 million people worldwide suffer head injuries each year while engaged in military, fire rescue, industrial production, sports, driving, and other activities. Among these people, about half will experience one or more traumatic brain injuries (TBI), as well as injuries to the eyes, ears, and neck.

[0003] Brain injury has become a characteristic trauma in military operations and fire rescue, with traumatic brain injury caused by blast shock waves being the most prevalent type. The explosive charge generates enormous energy, which, through medium compression, forms a shock wave, causing a sudden increase in temperature and pressure, resulting in damage to the internal structure of the skull, eardrums, and facial organs. Eye injuries mainly occur during sports activities and driving, manifesting as damage to ocular surface tissues such as the cornea, conjunctiva, and sclera, as well as soft tissue injuries, ocular surface abrasions, and orbital fractures, caused by blunt force trauma, sharp object punctures, or airbag ejection. Neck injuries manifest as damage to the neck structures caused by mechanical external forces.

[0004] Manufacturers and scholars have been working to improve protective devices and testing methods to reduce the incidence of head injuries. In the current technology, the protective performance of protective equipment is mainly tested by the following two methods.

[0005] The first approach is to establish a finite element model of the human body based on research on foreign cadaver experiments. All existing finite element models suffer from the following problems: (1) the geometric approximation and discretization level of the finite element model cannot realistically approximate the real human body; (2) how to obtain assumptions about the mechanical properties and material parameters of human tissues to more closely approximate the real human body; and (3) how to conduct experimental verification based on simulation data. Therefore, given the technical and ethical issues of cadaver research, many models have only been verified theoretically or in local mechanical aspects based on existing low-speed impact tests, and in most impact test conditions, they differ significantly from the actual situation.

[0006] The second method is to use HybridIII series dummies for impact testing. However, the physical dummy head model used for impact testing is relatively simple and cannot represent the external and internal anatomical structure of the human head. The test results obtained through physical dummy experiments can only reflect the protective performance of protective equipment in a one-sided way, which has obvious limitations. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of existing technologies by providing a dummy head injury testing device for impact testing. This testing device has good biosimulation and can more realistically and comprehensively assess the risk of head injury.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A dummy head injury testing device for impact testing includes a head assembly, the head assembly comprising:

[0010] A skull having a accommodating cavity, an eye socket being provided on the skull, and a bionic eyeball being provided in the eye socket;

[0011] Brain tissue, including bionic brain tissue and bionic cerebrospinal fluid, both of which fill the accommodating cavity of the skull;

[0012] The head skin has an opening corresponding to the position of the bionic eyeball. An auricle structure is formed on the head skin, and the head skin extends to the dummy's chin and upper neck. The head skin includes a head skin body covering the outside of the skull and a flexible sensing skin disposed on the outer surface of the head skin body. The flexible sensing skin includes a flexible base layer, conductive electrodes disposed on both ends of the flexible base layer, and an insulating layer covering the conductive electrodes. Multiple conductive electrodes are disposed at intervals on both ends, and the conductive electrodes on both ends are orthogonally arranged to form an array structure. The material of the flexible base layer includes silicone rubber and conductive materials. The flexible sensing skin is disposed at the location where skin pressure needs to be tested.

[0013] The sensing device includes at least an eye pressure sensor, an ear overpressure sensor, a head center of mass acceleration sensor, a head angular acceleration sensor, a neck sensor, a skin pressure sensor, a brain tissue strain sensor, and a skull strain sensor.

[0014] In some embodiments, the conductive material includes nickel powder and liquid gallium indium alloy.

[0015] In some embodiments, the conductive material further includes conductive ink.

[0016] In some embodiments, the raw materials of the flexible substrate layer further include an antioxidant stabilizer, which, by mass percentage, comprises 68.0%-72.0% silicone rubber, 13.5%-15.0% liquid gallium indium alloy, 4.5%-5.0% nickel powder, 9.0%-10.0% conductive ink, and 1.0%-2.0% antioxidant stabilizer.

[0017] In some embodiments, the silicone rubber comprises 69.0%-71.0% by weight, liquid gallium indium alloy comprises 14.0%-14.5%, nickel powder comprises 4.6%-4.8%, conductive ink comprises 9.3%-9.8%, and antioxidant stabilizer comprises 1.3%-1.7%.

[0018] In some embodiments, the bionic eyeball includes a cornea, a sclera, and a vitreous body; the sclera is formed into a spherical shell structure from collagen fiber material, with an opening at the front of the shell; the cornea is formed into an arc-shaped sheet structure from hydroxyethyl methacrylate material, and the cornea is disposed at the opening of the sclera; the vitreous body fills the closed space formed by the sclera and the cornea, and the vitreous body is formed from a hydrogel material.

[0019] In some embodiments, the hydrogel material is selected as an injectable, non-swelling Tetra-PEG hydrogel material, and the vitreous body is injected through the cornea into the closed space formed by the sclera and the cornea.

[0020] In some embodiments, the method of forming the skull includes:

[0021] (1) Obtain the geometry of the external and internal structures of the human head through medical MRI or CT scans;

[0022] (2) Establish a 3D model of the skull and divide the skull into an upper skull model and a lower skull model;

[0023] (3) Simplify the original topological structure of the skull and brain in the upper skull model and the lower skull model, ignore small features, and perform smoothing processing;

[0024] (4) Hollow out the interior of the upper skull model and the lower skull model, and hollow out the bottom of the lower skull model to form a sensor mounting platform at the bottom of the lower skull model;

[0025] (5) The upper skull is formed by 3D printing the upper skull model, and the lower skull is formed by 3D printing the lower skull model;

[0026] (6) The upper skull and the lower skull are fixedly connected, and a sealing structure is provided between the joint of the upper skull and the lower skull to seal the cavity formed between them.

[0027] In some embodiments, the biomimetic brain tissue is made of Dow Corning Sylgard 527 silicone rubber material.

[0028] In some embodiments, the biomimetic cerebrospinal fluid is formed from Clearco CAS#107-51-7 low-viscosity silicone oil.

[0029] In some embodiments, the eye pressure sensor is disposed at the eye socket position, and the bionic eyeball is disposed on the eye pressure sensor; the ear overpressure sensor is disposed at the position of the skull corresponding to the human ear, and the ear overpressure sensor extends from the auricular structure of the scalp to the outside of the scalp; the head center of mass acceleration sensor is disposed at the head center of mass position; the skin pressure sensor is disposed on the flexible sensing skin; the brain tissue strain sensor is embedded in the bionic brain tissue; and the skull strain sensor is disposed on the inner surface of the skull.

[0030] The present invention also provides a method for testing head injury of a dummy in an impact test, wherein the test is performed based on the testing device described in any of the above claims, and the testing method includes:

[0031] (1) The flexible sensing skin is installed at the location on the head skin body where skin pressure needs to be measured;

[0032] (2) Install each sensor;

[0033] (3) Fix the head assembly to the test environment and connect each sensor to the data acquisition device;

[0034] (4) Conduct impact tests, acquire data from each sensor through a data acquisition device, and assess the risk of head injury.

[0035] Due to the application of the above technical solutions, the present invention has the following advantages compared with the prior art: The dummy head injury testing device for impact testing of the present invention combines the advantages of finite element dummy models and physical dummy models, has a relatively complex biomimetic head structure, good biosimulation, and is closer to the structure of a real human head, making the test results closer to the real situation; moreover, the testing device has multiple sensor configuration schemes, which can obtain more head injury data for assessing head injury risk, thereby more comprehensively reflecting the protective performance of protective equipment. Attached Figure Description

[0036] Appendix Figure 1 This is a three-dimensional schematic diagram of the dummy head injury testing device for impact testing in this embodiment;

[0037] Appendix Figure 2 This is a three-dimensional schematic diagram of the dummy head injury testing device for impact testing in this embodiment (the head skin is removed from the head assembly);

[0038] Appendix Figure 3 This is an exploded schematic diagram of the skull containing bionic brain tissue in the dummy head injury testing device for impact testing in this embodiment.

[0039] Appendix Figure 4This is a three-dimensional schematic diagram of the lower skull in the dummy head injury testing device for impact testing in this embodiment;

[0040] Appendix Figure 5 This is a three-dimensional schematic diagram of the bionic brain tissue in the dummy head injury testing device for impact testing in this embodiment;

[0041] Appendix Figure 6 This is a schematic diagram of the bionic eyeball in the dummy head injury testing device for impact testing in this embodiment;

[0042] Appendix Figure 7 This is an overall schematic diagram of the flexible sensing skin in the dummy head injury testing device for impact testing in this embodiment.

[0043] Appendix Figure 8 This is a cross-sectional schematic diagram of the flexible sensing skin in the dummy head injury testing device for impact testing in this embodiment.

[0044] Appendix Figure 9 This is a schematic diagram showing the installation positions of the neck sensor, eye pressure sensor, and ear overpressure sensor in the dummy head injury testing device for impact testing in this embodiment.

[0045] Appendix Figure 10 This is a schematic diagram showing the installation positions of the head center of mass acceleration sensor and the head angular acceleration sensor in the dummy head injury testing device for impact testing in this embodiment.

[0046] Appendix Figure 11 This is a three-dimensional schematic diagram of the neck assembly in the dummy head injury testing device for impact testing in this embodiment.

[0047] The components are as follows: 11. Upper skull; 12. Lower skull; 121. Sensor mounting platform; 122. Eye socket; 2. Bionic eyeball; 21. Cornea; 22. Sclera; 23. Vitreous body; 3. Bionic brain tissue; 41. Head skin body; 42. Flexible sensing skin; 421. Flexible basal layer; 422. Conductor electrode; 423. Insulating adhesive; 424. Insulating film; 51. Eye pressure sensor; 52. Ear overpressure sensor; 53. Neck sensor; 54. Head center of mass acceleration sensor; 55. Head angular acceleration sensor; 56. Sensor mounting block; 6. Neck assembly. Detailed Implementation

[0048] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0049] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0050] The dummy head injury testing device for impact testing of the present invention includes a head assembly. In this embodiment, the main external dimensions of the head assembly refer to the head dimensions of the 50th percentile adult male as specified in GB / T 10000-2023 "Anthropometric Dimensions of Chinese Adults". Specific dimensions are as follows: head length 187mm, head and neck length 246mm, head width 158mm, head height 231mm, head circumference 570mm, interpupillary distance 61mm, top-of-eye height 114mm, external width of both ears 187mm, and neck circumference 368mm.

[0051] like Figure 1 and Figure 2 As shown, the head assembly includes the skull, brain tissue, scalp skin, and sensing devices.

[0052] like Figure 3 As shown, the skull is divided into two parts, namely the upper skull 11 and the lower skull 12. The upper skull 11 and the lower skull 12 are fixedly connected by screws. After the upper skull 11 and the lower skull 12 are fixedly connected, a sealed cavity is formed between them, and the brain tissue is filled in the sealed cavity.

[0053] In this embodiment, the skull is formed using the following method:

[0054] (1) Obtain the geometry of the external and internal structures of the human head through medical MRI or CT scans. MRI or CT scan data can be used to construct a highly biomimetic skull model, which can improve the manufacturing success rate and save costs.

[0055] (2) Use the 3D medical image segmentation software Mimics to create a 3D model of the skull and segment the skull into an upper skull model and a lower skull model.

[0056] (3) The original topological structure of the skull and brain in the upper and lower skull models was simplified using Geomagic software, ignoring minor features and smoothing the surface. The model was simplified while maintaining a close resemblance to the real skull, making it easier to fabricate the skull.

[0057] (4) Hollow out the interiors of the upper and lower skull models to create cavities, forming cavities to accommodate brain tissue. Simultaneously, hollow out the bottom of the lower skull model to create a sensor mounting platform 121 at the bottom, such as... Figure 4 As shown.

[0058] (5) The upper skull 11 is formed by 3D printing the upper skull model, and the lower skull 12 is formed by 3D printing the lower skull model.

[0059] Both the upper skull 11 and the lower skull 12 are made of ABS material, which is easy to 3D print. Moreover, this material has the characteristics of high strength, corrosion resistance and high temperature resistance.

[0060] (6) The upper skull 11 and the lower skull 12 are fixedly connected, and a sealing structure is provided between the joint of the upper skull 11 and the lower skull 12 to form a sealed accommodating cavity between the upper skull 11 and the lower skull 12.

[0061] An eye socket 122 is formed on the skull. In this embodiment, the eye socket 122 is formed on the lower skull 12. Given that the HybridIII dummy's head structure lacks detailed facial features and cannot measure eye injuries, in this embodiment, a bionic eyeball 2 is provided at the eye socket 122 for measuring eye injuries during impact testing.

[0062] Because the structure of the eye is very complex, in order to obtain a bionic eyeball 2 that can be used for impact testing, the eye tissue needs to be simplified accordingly. The simplified bionic eyeball 2 includes the cornea 21, sclera 22, and vitreous body 23, such as... Figure 6 As shown.

[0063] The cornea 21 and sclera 22 form the outer layer of the bionic eyeball 2. Specifically, the sclera 22 is a spherical shell structure with an opening at the front. The cornea 21 is an arc-shaped sheet structure, positioned at the opening of the sclera 22. The vitreous humor 23 fills the enclosed space formed by the sclera 22 and cornea 21, as shown below. Figure 6 As shown.

[0064] The sclera 22 is mainly composed of collagen fibers and has a certain mechanical strength, which helps maintain the shape of the eyeball and protect its internal structures; therefore, it is made of polyethylene. The cornea 21 has a certain degree of tear resistance and is therefore made of hydroxyethyl methacrylate (PHEMA).

[0065] The vitreous body 23 is a fluid, transparent gel-like substance. The vitreous body 23, along with other intraocular structures, exerts pressure on external structures such as the sclera 22, creating intraocular pressure and providing support for the retina and the outer layer of the eyeball. Therefore, in this embodiment, the vitreous body 23 is formed using an injectable, non-swelling Tetra-PEG hydrogel material, which is injected through the cornea 21 into the enclosed space formed by the sclera 22 and the cornea 21.

[0066] This embodiment provides a method for preparing a bionic eyeball 2, which specifically includes the following steps:

[0067] (1) The sclera 22 is processed into a shell with an outer diameter of 24 mm and a thickness of 1 mm. An opening is provided at the front of the shell to install the cornea 21.

[0068] (2) The cornea 21 is made into an arc-shaped sheet with an outer diameter of 8 mm and a thickness of 1 mm.

[0069] (3) Adhere the cornea 21 to the opening of the sclera 22 and ensure the adhesion strength.

[0070] (4) 5.6 ml of Tetra-PEG hydrogel was extracted and injected through the cornea 21 into the closed space formed by the sclera 22 and the cornea 21, thereby forming a bionic eyeball 2 with an intraocular pressure of 16 mmHg.

[0071] The brain tissue includes bionic brain tissue 3 and bionic cerebrospinal fluid. The structure of bionic brain tissue 3 is as follows: Figure 5 As shown, the bionic brain tissue 3 and bionic cerebrospinal fluid are both filled in a sealed cavity formed between the upper skull 11 and the lower skull 12.

[0072] In this embodiment, the biomimetic brain tissue 3 is made of Dow Corning Sylgard 527 silicone rubber material to match its properties with those of brain tissue. The material properties of Sylgard 527 silicone rubber are as follows: density ρ = 0.97 g / cm³. 3 The bulk modulus K = 1.07 GPa, the transient shear modulus G0 = 1.2 kPa, and the steady-state shear modulus G ∞ =0.25 kPa.

[0073] Since real cerebrospinal fluid is quite similar in properties to water, in this embodiment, Clearco CAS#107-51-7 low-viscosity silicone oil with a density of 0.8–1.01 kg / m³ was used as a substitute for biomimetic cerebrospinal fluid. 3 Between these values, the kinematic viscosity is approximately 1.0 × 10⁻⁶ m³. 2 / s.

[0074] The method for creating and implanting brain tissue into the skull is as follows:

[0075] A certain proportion of Sylgard 527 silicone rubber AB material is mixed evenly and poured into a mold for room temperature curing. During the curing process, strain gauges or other sensors are embedded at the brain tissue locations that need to be observed in actual experiments. After curing, the biomimetic brain tissue 3 of this embodiment is formed. Then, the biomimetic brain tissue 3 is placed into the cavity of the lower skull 12, and biomimetic cerebrospinal fluid is poured into the cavity of the lower skull 12. The upper skull 11 and the lower skull 12 are then connected and sealed.

[0076] In this embodiment, the facial organs of the head assembly are specified as follows: Figure 1 As shown, the head skin has an opening corresponding to the position of the bionic eyeball 2, and an ear structure is formed on the head skin. The head skin extends to the dummy's chin and upper neck, thus realistically simulating a person wearing protective equipment such as a helmet and oxygen mask.

[0077] The head skin includes a head skin body 41, which covers the outside of the skull, and facial organs are formed on the head skin body 41. To ensure the head assembly has realistic biomimetic characteristics, the softness and smoothness of the head skin body 41 are close to those of a real person. Factors such as the shape, material, and manufacturing process of the skin have a significant impact on the test results. In this embodiment, the head skin body 41 uses silicone rubber as the matrix to simulate the skin of a dummy, so that the manufactured skin material conforms to the characteristics of human skin in terms of toughness, extensibility, and elasticity. In this embodiment, the head skin body 41 uses vinyl silicone rubber material, and the designed thickness of the head skin body 41 is 8-12 mm.

[0078] The raw materials for the head skin body 41 also include reinforcing agents, and the physical properties after vulcanization are medium strength and a density of 1.1–1.3 g / cm³. 3 Between these conditions, under ambient temperature of 25℃ and humidity of 45% to 75%, the Shore A hardness is 40±5HA, the tensile strength is 4 to 7MPa, the elongation at break is 200 to 300%, and the tear strength is 29 to 40kN / m.

[0079] The scalp also includes a flexible sensing skin 42, which is disposed on the outer surface of the scalp body 41. Specifically, the flexible sensing skin 42 is located on the scalp body 41 at the location where skin pressure needs to be tested.

[0080] The flexible sensing skin includes a flexible base layer 421. In order to enable the flexible sensing skin to have piezoresistive properties so as to convert external pressure signals into resistance signals and thus sense external pressure, in this embodiment, the raw materials of the flexible base layer 421 include silicone rubber and conductive materials.

[0081] Vinyl silicone rubber can be used. Conductive materials include nickel powder and liquid gallium indium alloy. To enhance conductivity and ensure stable conductivity, conductive ink is also included in addition to nickel powder and gallium indium alloy.

[0082] The raw materials for the flexible substrate 421 material also include antioxidant stabilizers.

[0083] The raw materials of the flexible substrate 421 material, by weight percentage, are as follows:

[0084] The composition comprises: vinyl silicone rubber 68.0%-72.0%; liquid gallium indium alloy 13.5%-15.0%; nickel powder 4.5%-5.0%; conductive ink 9.0%-10.0%; and antioxidant stabilizer 1.0%-2.0%. Preferably, the composition is: vinyl silicone rubber 69.0%-71.0%; liquid gallium indium alloy 14.0%-14.5%; nickel powder 4.6%-4.8%; conductive ink 9.3%-9.8%; and antioxidant stabilizer 1.3%-1.7%.

[0085] The preparation method of the flexible substrate 421 includes the following steps:

[0086] (1) Weigh each raw material according to the formula. Using vinyl silicone rubber as the base, add liquid gallium indium alloy and nickel powder as fillers to the liquid vinyl silicone rubber in sequence. Then add conductive ink to produce an elastic composite material with conductive properties. Each time a raw material is added, mix it evenly before adding the next raw material.

[0087] (2) Place the mold for making the flexible substrate 421 in an oven and heat it to 50-60℃ and keep it for 20-50 minutes. Then take out the mold and insert a temperature sensor to monitor the temperature of the mold in real time. Pour the mixed liquid elastic composite material into the heated mold and then immediately put it back into the oven and raise the temperature to 70-80℃. Bake at a constant temperature for 20-50 minutes and then cool it to make the flexible substrate 421.

[0088] In this conductive elastic composite material, the irregular shape of nickel, with its protrusions and sharp corners, increases the number of electrical contacts between the fillers. Gallium-indium alloy, with its high conductivity, forms microdroplets in the elastic composite material, allowing it to deform along with the material. The contact between the metal fillers ensures the conductivity of the elastic composite material. The resistivity of this material decreases significantly under mechanical deformation such as compression, tension, and bending.

[0089] The working principle of the flexible sensing skin 42 is as follows:

[0090] When the flexible sensing skin 42 is compressed, the nickel microparticles do not deform, while the gallium indium alloy, along with the vinyl silicone rubber substrate, is compressed along the direction of the force. The thickness of the vinyl silicone rubber substrate decreases in this direction, and the distance between the liquid gallium indium alloy droplets and the adjacent nickel microparticles also shortens, thus establishing a new conductive path and reducing resistivity. After the load is removed, the elastic composite material returns to its original shape due to its elasticity, and the resistance returns to its maximum. Rapid traversal and real-time transmission of array matrix signals are achieved through upper-computer programming control, and dynamic visualization of the array signals is realized by combining serial port interrupt programming.

[0091] To further achieve high-resolution sensing of skin impact signals, this embodiment designs a high-density array sensing structure based on flexible sensing skin with piezoresistive characteristics, ensuring that each array point can accurately sense changes in load when impacted.

[0092] Specifically, such as Figure 7 and Figure 8 As shown, the flexible sensing skin also includes wire electrodes 422, which are respectively disposed on both ends of the flexible substrate layer 421. Multiple wire electrodes 422 are disposed at intervals on both ends of the flexible substrate layer 421. The wire electrodes 422 on both ends of the flexible substrate layer 421 are orthogonally arranged to form an array structure. Each intersection point forms a piezoresistive sensing unit of "wire - flexible substrate layer 421 - wire".

[0093] The conductive electrodes 422 on both ends of the flexible substrate 421 are covered and fixed to the flexible substrate 421 by insulating adhesive 423, which also insulates them from the outside environment. An insulating film 424 is further covered on top of the insulating adhesive 423 for insulation and to encapsulate the entire structure. The insulating adhesive 423 and the insulating film 424 together form an insulating layer, such as... Figure 7 and Figure 8 As shown.

[0094] In this embodiment, a 12×12 array of units is used as the array structure of the flexible sensory skin. The specific preparation method includes the following steps:

[0095] (1) Take a flexible substrate 421 sample with a length of 6cm, a width of 6cm and a thickness of 0.2mm. The wire electrode 422 is made of copper wire with a diameter of 0.3mm.

[0096] (2) Punch 12 holes through the top and bottom ends of the sample at each edge of the sample. The two ends of each copper wire on each end of the sample pass through the corresponding two holes, and the copper wires are arranged in sequence on the top and bottom ends of the sample.

[0097] (3) Use double-sided tape to initially fix each copper wire to the end face of the sample to ensure that the copper wires are neatly arranged and do not touch each other.

[0098] (4) Cover the entire structure with insulating adhesive 423 to insulate it from the outside world, fix the copper wire to ensure the copper wire adheres to the sample, and wrap the exposed copper wire extending from the pinhole with heat shrink tubing for insulation.

[0099] (5) Cover both ends of the sample with insulating film 424, and then connect each copper wire to the piercing insulation displacement connector and connect it to the ribbon cable.

[0100] According to the test requirements, the size, shape, dimensions, and array point arrangement characteristics of the sample can be adjusted. The formulation of the flexible substrate 421 can also be adjusted to make it more conductive and suitable for high-speed impact scenarios in different parts of the human body.

[0101] The sensing device is used to measure head injury data after impact. The test data mainly includes: head center of mass acceleration, head angular acceleration, neck six-dimensional force, eye pressure, ear overpressure, skin pressure, brain tissue strain, skull strain, etc. By placing corresponding sensors in appropriate locations, detailed head injury data can be obtained, thereby evaluating the biomechanical damage indicators of head injury.

[0102] The sensing device includes at least an eye pressure sensor 51, an ear overpressure sensor 52, a neck sensor 53, a head center of mass acceleration sensor 54, a head angular acceleration sensor 55, a skin pressure sensor, a brain tissue strain sensor, and a skull strain sensor.

[0103] like Figure 9 As shown, the eye pressure sensor 51 is fixed to the eye socket 122 of the skull with fastening screws, and the bionic eyeball 2 is attached to the surface of the eye pressure sensor 51. When an object hits or scratches the eye, the eye pressure sensor 51 can detect the impact force, and by observing the physical state of the bionic eyeball 2, it can be determined whether there is a risk of eye damage.

[0104] like Figure 1 , Figure 2 and Figure 9 As shown, the ear overpressure sensor 52 is fixed to the left and right sides of the skull via its own threads, corresponding to the position of the human ear. The ear overpressure sensor 52 extends from the auricle structure of the scalp to the outside of the scalp. When a pressure shock wave occurs, the ear overpressure sensor 52 will measure the overpressure data, and the test data will be used to assess whether there is a risk of ear damage.

[0105] like Figure 9As shown, the neck sensor 53 is a six-dimensional force sensor for the neck. The sensor is mounted on the sensor mounting platform 121 of the lower skull 12 by screws. When subjected to impact, the force and torque of the neck can be measured by the sensor, and the risk of neck injury can be assessed by the test data.

[0106] like Figure 10 As shown, a sensor mounting block 56 is provided on the neck sensor 53. Three head center-of-gravity acceleration sensors 54 and three head angular acceleration sensors 55 are mounted on the sensor mounting block 56. The three head center-of-gravity acceleration sensors 54 are mounted at the head center of gravity position by screws and can measure the acceleration of the head center of gravity in the XYZ directions. The three head angular acceleration sensors 55 are used to measure the angular acceleration of the head in the XYZ directions.

[0107] A skin pressure sensor is installed on the flexible sensing skin 42. The skin pressure sensor, in conjunction with the flexible sensing skin 42, enables real-time display of the skin's pressure process.

[0108] Brain tissue strain sensors are pre-embedded at the locations of the brain tissue to be observed during the curing of the bionic brain tissue 3 within the mold. When a shock wave occurs, the brain tissue strain sensors will measure the strain data of the brain tissue, and the test data will be used to assess the risk of brain tissue damage.

[0109] Skull strain sensors are placed on the inner surface of the skull to measure the deformation of the skull after it has been subjected to an impact.

[0110] The testing device may also include a neck assembly 6, which may adopt the neck assembly structure of the HybridIII series dummy, such as... Figure 11 As shown. During impact testing, the head assembly is mounted on the neck assembly. Of course, the testing device may not include the neck assembly 6, and other fixtures may be used to secure the head assembly during impact testing.

[0111] The testing method for testing dummy head injuries using this testing device in impact tests includes the following steps:

[0112] (1) A flexible sensing skin 42 is set at the location on the head skin body 41 where skin pressure needs to be measured.

[0113] (2) Install the eye pressure sensor 51, ear overpressure sensor 52, neck sensor 53, head center of mass acceleration sensor 54, head angular acceleration sensor 55, skin pressure sensor and skull strain sensor into their respective positions.

[0114] (3) Fix the head assembly in the test environment and connect each sensor to the data acquisition device.

[0115] (4) Conduct impact tests, acquire data from each sensor through a data acquisition device, and assess the risk of head injury.

[0116] In summary, this testing device has the following advantages:

[0117] (1) The head assembly has both the structure of human head anatomy and can be connected to a physical dummy, with good biosimulation and good versatility.

[0118] (2) The skull of the device is constructed using MRI or CT scan data, which is close to the human body and has a good biosimulation.

[0119] (3) The device has multiple sensor configuration options, which can obtain more head injury data for assessing head injury risk.

[0120] (4) The head skin of the device has flexible sensing skin with piezoresistive properties. By adding a material with conductive properties to the vinyl silicone rubber base material and designing an array sensing matrix structure, the real-time status display of the skin under pressure can be realized.

[0121] (5) The device has a certain degree of bionic structure in the eye. The impact force of the eye can be obtained through the eye pressure sensor. By observing the physical state of the bionic eyeball, it can be determined whether there is a risk of eye damage.

[0122] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A dummy head injury testing device for impact testing, comprising a head assembly, characterized in that: The head assembly includes: A skull having a accommodating cavity, an eye socket being provided on the skull, and a bionic eyeball being provided in the eye socket; Brain tissue, including bionic brain tissue and bionic cerebrospinal fluid, both of which fill the accommodating cavity of the skull; The head skin has an opening corresponding to the position of the bionic eyeball. An auricle structure is formed on the head skin, and the head skin extends to the dummy's chin and upper neck. The head skin includes a head skin body covering the outside of the skull and a flexible sensing skin disposed on the outer surface of the head skin body. The flexible sensing skin includes a flexible base layer, conductive electrodes disposed on both ends of the flexible base layer, and an insulating layer covering the conductive electrodes. Multiple conductive electrodes are disposed at intervals on both ends, and the conductive electrodes on both ends are orthogonally arranged to form an array structure. The material of the flexible base layer includes silicone rubber and conductive materials. The flexible sensing skin is disposed at the location where skin pressure needs to be tested. The sensing device includes at least an eye pressure sensor, an ear overpressure sensor, a head center of mass acceleration sensor, a head angular acceleration sensor, a neck sensor, a skin pressure sensor, a brain tissue strain sensor, and a skull strain sensor.

2. The dummy head injury testing device for impact testing according to claim 1, characterized in that: The conductive material includes nickel powder and liquid gallium indium alloy.

3. The dummy head injury testing device for impact testing according to claim 2, characterized in that: The conductive material also includes conductive ink.

4. The dummy head injury testing device for impact testing according to claim 3, characterized in that: The raw materials of the flexible substrate layer also include an antioxidant stabilizer, which, by mass percentage, comprises 68.0%-72.0% silicone rubber, 13.5%-15.0% liquid gallium indium alloy, 4.5%-5.0% nickel powder, 9.0%-10.0% conductive ink, and 1.0%-2.0% antioxidant stabilizer.

5. The dummy head injury testing device for impact testing according to claim 4, characterized in that: The composition, by weight percentage, is 69.0%-71.0% silicone rubber, 14.0%-14.5% liquid gallium indium alloy, 4.6%-4.8% nickel powder, 9.3%-9.8% conductive ink, and 1.3%-1.7% antioxidant stabilizer.

6. The dummy head injury testing device for impact testing according to claim 1, characterized in that: The bionic eyeball includes a cornea, a sclera, and a vitreous body; the sclera is a spherical shell structure formed of collagen fiber material, with an opening at the front of the shell; the cornea is an arc-shaped sheet structure formed of hydroxyethyl methacrylate material, and the cornea is located at the opening of the sclera; the vitreous body fills the closed space formed by the sclera and the cornea, and the vitreous body is formed of hydrogel material.

7. The dummy head injury testing device for impact testing according to claim 6, characterized in that: The hydrogel material is selected as injectable Tetra-PEG non-swelling hydrogel material, and the vitreous body is injected through the cornea into the closed space formed by the sclera and the cornea.

8. The dummy head injury testing device for impact testing according to claim 1, characterized in that: The method of forming the skull includes: (1) Obtain the geometry of the external and internal structures of the human head through medical MRI or CT scans; (2) Establish a 3D model of the skull and divide the skull into an upper skull model and a lower skull model; (3) Simplify the original topological structure of the skull and brain in the upper skull model and the lower skull model, ignore small features, and perform smoothing processing; (4) Hollow out the interior of the upper skull model and the lower skull model, and hollow out the bottom of the lower skull model to form a sensor mounting platform at the bottom of the lower skull model; (5) The upper skull is formed by 3D printing the upper skull model, and the lower skull is formed by 3D printing the lower skull model; (6) The upper skull and the lower skull are fixedly connected, and a sealing structure is provided between the joint of the upper skull and the lower skull to seal the cavity formed between them.

9. The dummy head injury testing device for impact testing according to claim 1, characterized in that: The biomimetic brain tissue is made of Dow Corning Sylgard 527 silicone rubber material.

10. The dummy head injury testing device for impact testing according to claim 1, characterized in that: The biomimetic cerebrospinal fluid is formed from Clearco CAS#107-51-7 low-viscosity silicone oil.

11. The dummy head injury testing device for impact testing according to claim 1, characterized in that: The eye pressure sensor is located at the eye socket, and the bionic eyeball is located on the eye pressure sensor; the ear overpressure sensor is located on the skull at the position corresponding to the human ear, and the ear overpressure sensor extends from the auricular structure of the scalp to the outside of the scalp. The head center of mass acceleration sensor is located at the head center of mass; the skin pressure sensor is located on the flexible sensing skin; and the brain tissue strain sensor is embedded in the bionic brain tissue. The skull strain sensor is disposed on the inner surface of the skull.

12. A method for testing head injury in a dummy during impact testing, characterized in that: The test is performed using the testing apparatus according to any one of claims 1 to 11, and the testing method includes: (1) The flexible sensing skin is installed at the location on the head skin body where skin pressure needs to be measured; (2) Install each sensor; (3) Fix the head assembly to the test environment and connect each sensor to the data acquisition device; (4) Conduct impact tests, acquire data from each sensor through a data acquisition device, and assess the risk of head injury.

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