阅读说明：本技术 一种用于测试的仿生口腔结构及其应用 (Bionic oral cavity structure for testing and application thereof ) 是由 俞经虎 曹澍 钱善华 曹毅 周星宇 于浩 于 2019-09-11 设计创作，主要内容包括：本发明提供了一种用于测试的仿生口腔结构及其应用,其能解决现有的仿生口腔结构实际测试还有待改善的技术问题。一种用于测试的仿生口腔结构,其包括上颌、下颌、驱动单元、传感器和控制器,其特征在于：牙龈为软质弹性材料制得,牙龈的基体设有穿孔、自穿孔上端开口向上延伸形成的盖帽部,牙齿包括均由硬质材料制得的磨牙和种植体,种植体的上端贯穿牙龈的穿孔后伸入盖帽部,牙龈和种植体均可拆卸地固定于安装板上,传感器为柔性传感器,柔性传感器覆盖盖帽部,磨牙底部设有沉孔,磨牙安装于牙龈上,由柔性传感器、盖帽部和种植体的上端构成的整体嵌入沉孔内并且与沉孔为紧配合。(The invention provides a bionic oral cavity structure for testing and application thereof, which can solve the technical problem that the actual test of the existing bionic oral cavity structure needs to be improved. A bionic oral cavity structure for testing, which comprises an upper jaw, a lower jaw, a driving unit, a sensor and a controller, and is characterized in that: the gum is made for soft elastic material, the base member of gum is equipped with the perforation, upwards extend the block portion that forms from perforation upper end opening, the tooth includes molar and the implant made by hard material, stretch into the block portion after the perforation that the upper end of implant runs through the gum, the equal detachably of gum and implant is fixed in on the mounting panel, the sensor is flexible sensor, flexible sensor covers the block portion, the molar bottom is equipped with the counter bore, molar installs on the gum, by flexible sensor, in the whole embedding counter bore that the upper end of block portion and implant constitutes and be the tight fit with the counter bore.)

1. a bionic oral cavity structure for testing comprises an upper jaw, a lower jaw, a driving unit, a sensor and a controller, wherein the upper jaw and the lower jaw respectively comprise teeth, gum and a mounting plate, the teeth, the gum and the mounting plate of the upper jaw are mounted on a static platform, the static platform is mounted on a rack, the teeth, the gum and the mounting plate of the lower jaw are mounted on a movable platform, the movable platform is connected with a driving device and can move in the vertical direction and the horizontal direction under the action of the driving unit, and the driving unit and the sensor are respectively in electric control connection with the controller; the method is characterized in that:

the gum is made of soft elastic materials, a base body of the gum is provided with a through hole which is arranged from top to bottom and a cover part which is formed by extending upwards from an opening at the upper end of the through hole, teeth comprise a molar and an implant which are made of hard materials, the upper end of the implant penetrates through the through hole of the gum and then extends into the cover part, the gum and the implant are detachably fixed on the mounting plate, the sensor is a flexible sensor which covers the cover part, the flexible sensor is at least provided with 1 sensing unit which is opposite to the top of the cover part and at least provided with more than 2 sensing units which are uniformly distributed around the side part of the cover part, the bottom of the molar is provided with a counter bore, the molar is arranged on the gum, and the whole body formed by the flexible sensor, the cover part and the upper end of the implant is embedded into the counter bore and is in tight fit with the counter bore, the molar, the flexible sensor, the cap part and the implant are sequentially and tightly attached.

2. a biomimetic oral structure for testing according to claim 1, wherein: the gum adopts silica gel to make, under non-test state, the cap portion is in the elasticity compression state and can further compress under the effect of external force under the effect of molar tight fit.

3. A biomimetic oral structure for testing according to claim 1, wherein: under the non-test state, the inside wall and the top wall of the counter bore are tightly attached to the non-induction detection end of the flexible sensor, the outside wall and the outer top wall of the cap part are tightly attached to the induction detection end of the flexible sensor, and the inside wall and the inner top wall of the cap part are tightly attached to the outside wall and the outer top wall of the upper end of the implant.

4. A biomimetic oral structure for testing according to claim 1, wherein: the implant is in threaded fit with the mounting plate and is fastened by a nut.

5. a biomimetic oral structure for testing according to claim 1, wherein: the lower terminal surface of base member with the mounting panel laminating, the planting body runs through from bottom to top the mounting panel with the base member.

6. A biomimetic oral structure for testing according to claim 1, wherein: the lower jaw is provided with a tongue, and the tongue is made of silica gel and is installed on the installation plate.

7. A biomimetic oral structure for testing according to claim 1, wherein: the upper jaw and the lower jaw are respectively provided with an eddy current sensor corresponding to each tooth, the eddy current sensors of the upper jaw part are arranged right above the implant and are arranged at intervals, and the eddy current sensors of the lower jaw part are arranged right below the implant and are arranged at intervals.

8. A biomimetic oral structure for testing according to claim 1, wherein: the driving unit is provided with 3 pairs and uniformly distributed around the movable platform, the driving unit comprises a motor, a screw rod nut, a sliding block, a guide pillar, a connecting rod and a spherical hinge, the output end of the motor is connected with the screw rod, two ends of the screw rod and the guide pillar are respectively supported on the supporting plate and are vertically arranged, the screw rod nut is matched with the screw rod and is fixedly connected with the sliding block, the sliding block is in guiding fit with the guide pillar, two ends of the connecting rod are respectively connected with the sliding block and the movable platform through the spherical hinge, and the motor and the supporting plate are fixed on the rack.

9. use of the biomimetic oral structure of any of claims 1 ~ 8 in food physical property detection.

10. use of a biomimetic oral structure according to any of claims 1 ~ 8 in a denture fatigue test.

Technical Field

The invention relates to the technical field of bionic machinery, in particular to a bionic oral cavity structure for testing and application thereof.

Background

The existing bionic oral cavity structure comprises an upper tooth, a lower tooth and a corresponding sensor, wherein the upper tooth is arranged at the upper part of a frame, the lower tooth is fixed in a cavity of a container and is positioned below the upper tooth, the container is fixed on a movable platform, and the upper part of the container is provided with an opening; the chewing driving device is connected with the movable platform and used for lifting the movable platform upwards to enable the lower teeth to move relative to the upper teeth, and various actions such as up-down occlusion, left-right grinding and cutting, incisor cutting and the like are realized by controlling the driving differently, so that the purpose of bionic chewing is achieved.

Although the existing bionic oral cavity structure achieves the aim of bionic chewing, the actual test of the bionic oral cavity structure still needs to be improved. Chinese patent 201010255196.0 discloses a bionic detection robot for food physical properties, which also has a bionic oral cavity structure, wherein pressure sensors are arranged on the surfaces of upper and lower teeth to collect data information of the force of food acting on the teeth, so as to embody the physical properties of food under different chewing degrees. However, the traditional pressure sensor has a large volume, and the structure of the surface of the tooth can be influenced by being mounted on the surface of the tooth, so that the purpose of bionic chewing is influenced.

Disclosure of Invention

the invention provides a bionic oral cavity structure for testing and application thereof, which can solve the technical problem that the actual test of the existing bionic oral cavity structure needs to be improved.

the technical scheme is that the bionic oral cavity structure for testing comprises an upper jaw, a lower jaw, a driving unit, a sensor and a controller, wherein the upper jaw and the lower jaw respectively comprise teeth, gum and a mounting plate, the teeth, gum and mounting plate of the upper jaw are mounted on a static platform, the static platform is mounted on a rack, the teeth, gum and mounting plate of the lower jaw are mounted on a movable platform, the movable platform is connected with a driving device and can move along the vertical direction and the horizontal direction under the action of the driving unit, and the driving unit and the sensor are respectively in electric control connection with the controller; the method is characterized in that:

The gum is made of soft elastic materials, a base body of the gum is provided with a through hole which is arranged from top to bottom and a cover part which is formed by extending upwards from an opening at the upper end of the through hole, teeth comprise a molar and an implant which are made of hard materials, the upper end of the implant penetrates through the through hole of the gum and then extends into the cover part, the gum and the implant are detachably fixed on the mounting plate, the sensor is a flexible sensor which covers the cover part, the flexible sensor is at least provided with 1 sensing unit which is opposite to the top of the cover part and at least provided with more than 2 sensing units which are uniformly distributed around the side part of the cover part, the bottom of the molar is provided with a counter bore, the molar is arranged on the gum, and the whole body formed by the flexible sensor, the cover part and the upper end of the implant is embedded into the counter bore and is in tight fit with the counter bore, the molar, the flexible sensor, the cap part and the implant are sequentially and tightly attached.

furthermore, the gum adopts silica gel to make, and under non-test state, the cap portion is in the elasticity compression state and can further compress under the effect of external force under the effect of molar tight fit.

Further, under the non-test state, the inside wall, the roof of counter bore all with the non-response sense terminal of flexible sensor closely laminates, the lateral wall, the outer roof of lid portion all with the response sense terminal of flexible sensor closely laminates, the inside wall, the interior roof of lid portion all with the lateral wall, the outer roof of planting body upper end closely laminate.

furthermore, the upper jaw and the lower jaw are respectively provided with an eddy current sensor corresponding to each tooth, the eddy current sensors of the upper jaw part are arranged right above the implant and are arranged at intervals, and the eddy current sensors of the lower jaw part are arranged right below the implant and are arranged at intervals.

Furthermore, the driving unit is provided with 3 pairs and uniformly distributed around the movable platform, the driving unit comprises a motor, a lead screw nut, a sliding block, a guide pillar, a connecting rod and a spherical hinge, the output end of the motor is connected with the lead screw, two ends of the lead screw and the guide pillar are respectively supported on the supporting plate and are vertically arranged, the lead screw nut is matched with the lead screw and is fixedly connected with the sliding block, the sliding block is in guiding fit with the guide pillar, two ends of the connecting rod are respectively connected with the sliding block and the movable platform through the spherical hinge, and the motor and the supporting plate are fixed on the rack.

further, the implant is screw-fitted to the mounting plate and fastened by a nut.

Further, the lower terminal surface of base member with the mounting panel laminating, the planting body runs through from bottom to top the mounting panel with the base member.

further, the lower jaw is provided with a tongue, and the tongue is made of silica gel and is installed on the installation plate.

The bionic oral cavity structure is applied to food physical property detection.

the bionic structure is applied to the fatigue test of the false tooth.

the bionic oral cavity structure has the following beneficial effects:

(1) The sensor and the gum are both of flexible structures, the gum is additionally provided with a cap part for coating the upper end of the implant, the flexible sensor is arranged between the inner side of a counter bore of the molar and the cap part, meanwhile, the molar, the flexible sensor, the cap part and the implant are sequentially and tightly attached to each other, after the upper and lower teeth and food are subjected to extrusion action or/and shearing action, force is transmitted to the cap part of the gum by the molar and the flexible sensor, the cap part and the gum are integrated and are made of soft elastic materials, the molar at the outer side and the implant at the inner part are made of hard materials, and in the force transmission action process, the cap part is subjected to obvious elastic deformation which can be more easily detected by the flexible sensor and converted into the change condition of the load required to be collected;

(2) the flexible sensor is arranged between the counter bore of the molar and the cap part of the gum, and cannot be contacted and rubbed with food, so that on one hand, bionic chewing is prevented from being influenced, and on the other hand, the service life of the flexible sensor is ensured;

(3) in the food texture detection experiment, different ways of chewing action of food materials are required, for example, the food materials are bitten up and down to generate extrusion action, the food materials are ground and cut left and right to generate shearing action, the flexible sensor covering the cap part can simultaneously detect forces in different directions generated by the extrusion action and the shearing action for detection, particularly, when the top of the cap part is further compressed in the up-and-down biting process, the part of the flexible sensor covering the top can feed back the stress condition in the up-and-down direction, when the side part of the cap part is further compressed in the left and right grinding and cutting processes, the part of the flexible sensor covering the top part can feed back the stress condition in the left and right directions, meanwhile, the stress condition is directly fed back from the flexible sensor of each tooth contacted with food, and the detected load is closer to the real load condition of a single tooth, so that the detection mode is more consistent with the bionic design;

(4) In the artificial tooth fatigue test experiment, implants of teeth at different positions need to be detected respectively, in the bionic oral cavity structure, the implants, the mounting plate and the gum are detachably connected, the implants of the teeth at different positions are convenient to replace and detect, the stress threshold and the fracture condition of the implants are detected through feedback of the flexible sensor, the implants generate displacement after loosening and are fed back through the metal eddy current sensor, and the stress threshold, the fracture and the damage condition of the molar teeth are accurately judged through stress feedback and displacement feedback, so that the detection is more accurate.

drawings

fig. 1 is a schematic structural diagram of a bionic oral cavity structure of the invention.

Fig. 2 is a schematic view of the structure of the lower jaw of the present invention, wherein some teeth are not installed.

Figure 3 is a cross-sectional view of the mating of the teeth, gums and mounting plate of the present invention.

Fig. 4 is a schematic structural diagram of a driving unit according to the present invention.

Detailed Description

as shown in fig. 1 to 4, a bionic oral cavity structure for testing comprises an upper jaw, a lower jaw, a driving unit, a sensor and a controller, wherein the upper jaw and the lower jaw respectively comprise teeth 4, gum 5 and a mounting plate 6, the lower jaw is further provided with a tongue 7, the teeth 4, the gum 5 (namely, upper teeth and upper gums) of the upper jaw and the mounting plate 6 are mounted on a static platform 1, the static platform 1 is mounted on an upper mounting seat 3d of a rack, the teeth 4, the gum 5 (namely, lower teeth and lower gums) of the lower jaw and the mounting plate 6 are mounted on a movable platform 2, the tongue 7 is made of silica gel and is mounted on the mounting plate 6 of the lower jaw, the movable platform 2 is connected with a driving device and can move along the vertical direction and the horizontal direction under the action of the driving unit, and the sensor;

The gum 5 is made of soft elastic material, in the embodiment, the gum is made of silica gel material, the gum comprises a base body and a cap part which are integrally formed, the lower end surface of the base body 5a is attached to the mounting plate 6, the base body 5a is provided with a through hole which is arranged from top to bottom, and the cap part 5b is formed by extending upwards from an opening at the upper end of the through hole;

The teeth 4 comprise molars and implants 8 which are made of hard materials, the lower end of the implant 8 is in threaded fit with a mounting plate 6 and is fastened through a nut 10, the upper end of the implant 8 penetrates through a perforation of a gum 5 and then extends into a cap part 5b, the gum 5 and the implant 8 are both detachably fixed on the mounting plate 6, the sensor is a flexible sensor 9, the flexible sensor 9 covers the cap part 5b, the flexible sensor is provided with 1 sensing unit opposite to the top of the cap part and more than 2 sensing units uniformly distributed around the side part of the cap part, the bottom of the molars is provided with counter bores 4a, the molars are installed on the gum 5, the whole body formed by the flexible sensor 9, the cap part 5b and the upper end of the implant 8 is embedded into the counter bores 4a and is in tight fit with the counter bores 4a, under the non-test state, the cap part 5b is in an elastic compression state under the action of tight fit of the molars and can be further compressed under the action of external force, molar, flexible sensor 9, block portion 5b and planting body 8 closely laminate the setting in proper order, it is concrete, counter bore 4 a's inside wall, the roof all closely laminates with flexible sensor 9's non-response sense terminal (lateral surface promptly, outer roof), block portion 5 b's lateral wall, outer roof all closely laminates with flexible sensor 9's response sense terminal (medial surface promptly, interior roof), the inside wall of block portion 9, interior roof all with the lateral wall of the upper end of planting body 8, outer roof closely laminates.

the drive unit is equipped with 3 pairs and around moving 2 equipartitions of platform, the drive unit includes motor 11, lead screw 12, screw-nut, slider 15, guide pillar 13, connecting rod 17 and ball pivot 18, lead screw 12 is connected to motor 11's output, lead screw 12, guide pillar 13 both ends support respectively in backup pad 14 and all along vertical setting, screw-nut and lead screw 12 cooperation and with slider 15 fixed connection, slider 15 and guide pillar 13 direction cooperation, connecting rod 17 both ends are respectively through ball pivot 18 and the fixed connection support 16 of slider lateral part, move the platform 2 and be connected, motor 11, backup pad 14 is fixed in the lower installing frame 3b of frame. The 3 pairs of 6 driving units can realize six-degree-of-freedom motion of the movable platform, further realize the simulation of the lower jaw motion of the oral cavity when the person chews, and realize the simulation of the complete oral cavity of the person and the occlusion and grinding motion by matching with the upper jaw arranged on the static platform.

The rack comprises a bottom plate 3a, lower mounting frames 3b which correspond to the 3 pairs of driving units one by one are fixed on the bottom plate 3a, the upper ends of the lower mounting frames 3b are connected through an annular connecting plate 3c, and an upper mounting seat 3d is fixed on the connecting plate 3 c.

The parts of the flexible sensors 9 covering the top and the side of the cap part in the above embodiments are integrally formed, and a split structure may be adopted, that is, the first flexible sensor covers the top of the cap part, and the second flexible sensor covers the side of the cap part.

When the bionic oral cavity structure is used for detecting the physical properties of food, the sensor records the data of the deformation, stress and time of the food in the chewing process, and draws a stress-time curve, wherein the time is used as an abscissa, the stress is used as an ordinate, the detection value of the pressure sensor is positive, and the detection value of the tension sensor is negative; a deformation-time curve, with time as the abscissa and deformation as the ordinate; a stress-deformation curve, with deformation as abscissa and stress as ordinate; from these curves, the method of detecting the relevant physical property data is as follows.

Bite strength (hardness): the higher the force corresponding to the maximum peak on the stress-time curve, the harder the food product, the harder it will bite.

adhesiveness: the area of the inverted peak below the horizontal coordinate line on the stress-time curve represents the stickiness of the food, and the larger the absolute value of the value is, the stronger the stickiness of the food is, and the sticky mouthfeel of the food is.

Elasticity (breaking force): the stress-deformation curve is expressed by the product of the force corresponding to the maximum peak and the stretching distance, and the larger the value, the longer the stretching distance, the better the food elasticity.

Extensibility (stretching time): the larger the time taken from the start of stretching to the stretch-breaking of the food on the deformation-time curve, the better the extensibility.

Toughness: the product of cutting force and cutting distance when the food is cut off by chewing on the stress-deformation curve, namely the work done during cutting off; the larger the value, the better the toughness.

Maximum breaking force: the larger the value of the force corresponding to the maximum peak on the stress-deformation curve, the larger the force used when cutting the food. The bionic structure is applied to the fatigue test of the false tooth.

The bionic oral cavity structure is used for detecting the fatigue strength of the implant, an eddy current sensor 19 is additionally loaded corresponding to each tooth, taking the lower jaw as an example, the eddy current sensor 19 is connected with a counter bore 6a of a mounting plate of the lower jaw in an interference fit manner (or can be directly and fixedly mounted on a movable platform and extend into the counter bore 6 a), the position of a probe of the eddy current sensor 19 is adjusted to enable the probe to be opposite to the lower end face of the implant and arranged at intervals under a non-stressed or non-detection stressed state, the distance is about 1mm, the eddy current sensor of the upper jaw part is mounted opposite to the eddy current sensor of the lower jaw part, namely the probe is mounted above the implant at intervals and corresponds to the upper end face of the implant. The mounting plate and the nut simulate bone tissues, loosening generally occurs at the threaded connection position of the implant and the mounting plate, when the implant loosens, displacement can occur in the chewing stress process, for example, the implant rotates or deviates around the loosened part, the distance between a probe of the eddy current sensor 19 and the bottom surface of the implant can also change, the impedance of the eddy current sensor 19 also changes, and therefore displacement signals are converted into electric signals.

the method for detecting the fatigue strength of the implant by using the bionic oral cavity structure comprises the following steps:

(1) calibration is as follows

a. When the movable platform is unloaded, setting the current position as an initial position, and vertically moving upwards from the initial position;

b. when the upper jaw and the lower jaw are contacted with teeth, the movable platform immediately stops moving, and the current displacement S1 is recorded;

c. moving the platform to the initial position and placing a food sample;

d. the movable platform bears the food sample to move upwards, the movement is stopped after the food is contacted with the static platform, the displacement S2 is recorded, and the thickness of the food sample is S1-S2;

e. The movable platform returns to zero.

(2) Inputting preset parameters and modes of chewing operation, wherein the parameters of the chewing operation comprise a food compression ratio M, a shearing displacement coordinate, a preset cycle number N and the like.

(3) And (4) circularly executing the chewing operation until the test meets the preset circulation end condition.

The modes of the chewing operation include a compression chewing operation and/or a shear chewing operation;

the compression chewing operation of one cycle is embodied in that,

a. The movable platform moves vertically upwards, and the displacement amount is S2;

b. The movable platform continues to move vertically upwards, the displacement is d, and d is (S1-S2) M;

c. The movable platform moves vertically downwards, and the displacement is d.

Before the shearing chewing operation and circulation, a compression operation is also included;

The compression operation is, in particular,

a. The movable platform moves vertically upwards, and the displacement amount is S2;

b. the movable platform continues to move vertically upwards, the displacement is d, and d is (S1-S2) M;

The one-cycle shear chewing operation is embodied in that,

a. Horizontally moving the movable platform to (x, y);

b. The movable platform moves horizontally to (-x, -y).

The preset cycle end condition includes any one of the following end conditions,

a. Reaching the preset cycle times;

b. exceeding a preset stress threshold;

c. Exceeding a preset sample looseness amount;

d. The sample was broken.

And if the end condition a is met and the end conditions b, c and d are not met, determining that the to-be-detected implant is qualified. In the process of detecting the fatigue strength of the implant, if the physical property change of food is not considered, the stress detected by the flexible sensor is stable, but after a certain number of cycles of detection, the implant breaks, the stress changes suddenly and exceeds the stable stress value, the stable stress value is obtained according to the first several cycles of recording and can be an average value, the stress threshold value is increased by 5% -10% (other values can be also made and are related to the material characteristics) on the basis of the average value, and when the actually measured stress value exceeds the preset stress threshold value, the cycle is finished, and the implant is judged to be unqualified.

Unlike sample fracture after a certain number of cycles, which typically occurs in the initial cycle, it is associated with internal defects in the implant, such as cracks.

in the present invention,

the circuit portion of the flexible sensor is mounted as follows: the signal output end of the flexible sensor is connected with the amplifying circuit, the analog signal conditioned by the amplifying circuit is sent to the A/D converter, the analog signal is converted into a digital signal by the A/D converter and finally transmitted to a computer for analysis, and the external signal wire of the flexible sensor can be wired from the gum base body part.

The circuit part of the eddy current sensor is mounted as follows: the electric eddy current sensor is connected with the pre-processor, the pre-processor is connected with the power supply input end of the electric eddy current sensor, the output line is connected with the input port of the signal acquisition analyzer, and the output line of the final acquisition device is connected with the host of the computer.