An ear-worn temporomandibular joint movement monitoring system

Abstract

The present invention relates to the technical field of temporomandibular joint motion monitoring, and in particular to an ear-worn temporomandibular joint motion monitoring system. The system includes a memory and a processor, and the processor executes a computer program stored in the memory to implement the following steps: using an ear-worn temporomandibular joint motion monitoring device to obtain infrared points on the face of a person to be monitored within a monitoring period, and correcting the modulus of the infrared points according to facial rotation and acceleration; determining the corresponding motion law value based on the corrected modulus values ​​of all infrared points within the time neighborhood of each infrared point; determining the confidence level of each infrared point on the weakened side at each moment based on the corrected modulus values ​​of the infrared points within the time neighborhood of the infrared points on both sides of the face, and then screening the trajectory performance time period; and determining the condylar motion trajectory of the person to be monitored based on the position distribution of the infrared points within the trajectory performance time period. The present invention improves the accuracy of the condylar motion trajectory monitoring results.

Description

Technical Field

[0001] The present invention relates to the technical field of temporomandibular joint movement monitoring, and in particular to an ear-worn temporomandibular joint movement monitoring system. Background Art

[0002] The temporomandibular joint is a mobile joint in the oral craniomaxillofacial region. The fine structure of the temporomandibular joint works in synergy with the nerves and muscles of the oral and maxillofacial region to complete various important activities related to chewing, swallowing, speech, and facial expressions. Among the temporomandibular joint diseases, temporomandibular joint disorder is the most common. Temporomandibular joint disorders include masticatory muscle disorders, joint structure disorders, osteoarthritis, and osteoarthritis. This type of disease is characterized by three major clinical symptoms: abnormal mandibular movement, joint clicking and murmurs, and pain in the temporomandibular joint area and masticatory muscles. Since oral physiological functions such as chewing, swallowing, and speech are all completed through mandibular movement, changes in mandibular movement are one of the important reference factors for diagnosing temporomandibular joint diseases.

[0003] Accurately measuring temporomandibular joint motion is difficult due to its complex, small, and bilateral motion. Existing condylar motion measurement devices, dynamic MRI, and dynamic CT all have shortcomings when measuring condylar motion, resulting in inaccurate monitoring of temporomandibular joint motion. Summary of the Invention

[0004] In order to solve the problem of inaccurate monitoring results in existing methods for monitoring the motion trajectory of the temporomandibular joint, the present invention aims to provide an ear-worn temporomandibular joint motion monitoring system. The technical solutions adopted are as follows:

[0005] The present invention provides an ear-worn temporomandibular joint motion monitoring system, comprising a memory and a processor, wherein the processor executes a computer program stored in the memory to implement the following steps:

[0006] Using an ear-worn temporomandibular joint movement monitoring device to obtain infrared points on the face of the monitored person during the monitoring period and the modulus value of each infrared point;

[0007] The modulus values ​​of the infrared points on both sides of the face are corrected according to the face's rotation and acceleration during the monitoring period to obtain the corrected modulus values; the motion law value corresponding to each infrared point at each moment is determined based on the fluctuation of the corrected modulus values ​​of all infrared points in the time neighborhood of each infrared point;

[0008] Determine the confidence level of the weakened side and each infrared point on the weakened side at each moment based on the difference between the overall distribution of the corrected modulus values ​​of the infrared points in the time neighborhood of the infrared points on both sides of the face and the corrected modulus values ​​of the infrared points at corresponding positions on both sides of the face; and select the trajectory expression time period based on the distribution of the corrected modulus values ​​of the infrared points in the time neighborhood of the infrared points on the weakened side, the motion regularity value, and the confidence level.

[0009] The condylar motion trajectory of the monitored person is determined based on the relative position distribution of the infrared points at the same time and the position changes of the infrared points at different times within the trajectory performance time period.

[0010] Preferably, the step of correcting the modulus values ​​of the infrared points on both sides of the face according to the turning direction and acceleration of the face during the monitoring period to obtain the corrected modulus values ​​includes:

[0011] For any moment during the monitoring period:

[0012] If the monitored person turns his head at any moment, the side of the monitored person's face close to the ear-worn temporomandibular joint movement monitoring device is recorded as the first side, and the other side except the first side is recorded as the second side;

[0013] If the steering acceleration at any moment is less than 0, the difference between the constant 1 and the normalized value of the steering acceleration at any moment is recorded as a first difference, the product of the first difference and the modulus value of each infrared point on the first side is used as the corrected modulus value of each infrared point on the first side, and the modulus value of each infrared point on the second side is used as the corrected modulus value of each infrared point on the second side;

[0014] If the steering acceleration at any moment is greater than or equal to 0, the difference between the constant 1 and the normalized value of the steering acceleration at any moment is recorded as the second difference, the product of the second difference and the modulus value of each infrared point on the second side is used as the corrected modulus value of each infrared point on the second side, and the modulus value of each infrared point on the first side is used as the corrected modulus value of each infrared point on the first side.

[0015] Preferably, determining the motion regularity value corresponding to each infrared point at each moment according to the fluctuation of the corrected module values ​​of all infrared points in the time neighborhood of each infrared point includes:

[0016] For any moment during the monitoring period:

[0017] Performing curve fitting on the corrected modulus values ​​of all candidate infrared points within the time neighborhood at any moment to obtain a fitting curve;

[0018] According to the discrete degrees of the amplitudes of all extreme value points on the fitting curve and the discrete degrees of the time intervals of all adjacent extreme value points, the motion law value corresponding to the candidate infrared point at any time is obtained, and the discrete degrees of the amplitudes and the discrete degrees of the time intervals are both negatively correlated with the motion law value;

[0019] The candidate infrared point is any infrared point.

[0020] Preferably, determining the weakened side includes:

[0021] For any moment in the monitoring time period: calculate the average modulus value of all infrared points on each side at any moment; and take the side with the largest average modulus value as the weakened side.

[0022] Preferably, obtaining the confidence level of each infrared point on the weakened side at each moment includes:

[0023] The ratio of the average modulus value of all infrared points on the other side except the weakened side at any moment to the average modulus value of all infrared points on the weakened side is used as the weakening coefficient of the weakened side at any moment;

[0024] The product of the corrected modulus value of the infrared point to be analyzed at each moment in the time neighborhood of the any moment and the attenuation coefficient of the weakened side at the any moment is recorded as the first product corresponding to each moment in the time neighborhood; the difference between the first product corresponding to each moment in the time neighborhood and the corrected modulus value of the infrared point at the position corresponding to the infrared point to be analyzed on the other side of the time neighborhood except the weakened side at the same moment in the time neighborhood is calculated;

[0025] Obtaining the confidence level of the infrared point to be analyzed at any moment according to the difference between the module values, wherein the difference between the module values ​​is negatively correlated with the confidence level;

[0026] The infrared point to be analyzed is any infrared point on the weakened side.

[0027] Preferably, the method of comprehensively analyzing the corrected modulus distribution, motion regularity value, and confidence level of infrared points in the time neighborhood of the weakened side infrared point and screening the trajectory performance time period includes:

[0028] For any moment within the monitoring period: the difference between the maximum value and the second maximum value on the fitting curve corresponding to the infrared point to be analyzed is used as the movement performance of the infrared point to be analyzed at any moment;

[0029] Obtaining a preferred index at any moment according to the motion performance, motion regularity value, and confidence level of each infrared point on the weakened side at any moment;

[0030] Based on the optimal index at each moment in the monitoring period, the trajectory performance period is filtered.

[0031] Preferably, the optimal index at any moment is obtained based on the motion performance, motion regularity value, and confidence level of each infrared point on the weakened side at any moment, including:

[0032] For any moment during the monitoring period:

[0033] Calculate the normalized result of the product of the confidence and the motion regularity value of each infrared point on the weakened side at any time, and use the maximum value of the normalized result and the normalized value of the motion performance of each infrared point on the weakened side at any time as the characteristic value of each infrared point;

[0034] The average value of the characteristic values ​​of all infrared points at any moment is used as the preferred index at any moment.

[0035] Preferably, screening the trajectory performance time period based on the preference index of each moment in the monitoring time period includes: taking a time period consisting of adjacent moments whose preference index is greater than a preset preference threshold as the trajectory performance time period.

[0036] Preferably, the method of determining the condylar motion trajectory of the person to be monitored based on the relative position distribution of the infrared points at the same time and the position changes of the infrared points at different times within the trajectory representation time period includes:

[0037] At any moment within the trajectory representation time period: the vector pointed by the infrared camera to each infrared point is used as the vector of each infrared point; the jaw lines of both sides of the face of the monitored person are obtained respectively; the lowest point of the jaw line is used as the starting point, the interception point of a line segment of a preset first length on the jaw line is used as the starting point of the condyle vector, and a vector of a preset second length and a preset angle with the jaw line is obtained as the condyle vector; the position of the condyle feature point is determined based on the condyle vector;

[0038] The condyle motion trajectory of the monitored person is obtained according to the positions of the condyle feature points at all times within the trajectory performance time period.

[0039] Preferably, obtaining the modulus value of the infrared point includes: taking the distance from the infrared camera to the infrared point as the modulus value of the infrared point.

[0040] The present invention has at least the following beneficial effects:

[0041] The present invention first uses an ear-worn temporomandibular joint motion monitoring device to obtain infrared points on the face of the person to be monitored and the modulus of each infrared point during the monitoring period. Since the head of the person to be monitored rotates during the monitoring process, the ear-worn device mounted on the ear will rotate accordingly, causing the device on the side facing away from the rotation direction to have a relative displacement with the face, while the device on the side facing the rotation direction does not have a displacement due to being in close contact with the face, resulting in a large deviation in the modulus value of one side of the collected infrared point information. Therefore, the modulus value of the infrared point is corrected in combination with the face's rotation direction and acceleration, and the modulus value of the infrared point is corrected according to the time neighborhood of each infrared point. The fluctuation of the corrected modulus values ​​of all infrared points in the facial area was analyzed, and the movement regularity of each infrared point at each movement moment was evaluated. According to the difference between the overall distribution of the corrected modulus values ​​of the infrared points in the time neighborhood of the infrared points on both sides of the face, and the corrected modulus values ​​of the infrared points at corresponding positions on both sides of the face, the confidence level of each infrared point on the weakened side at each moment was determined. Then, the trajectory performance time period within the monitoring time period was screened out. The movement trajectory of the condyle was determined based on the relative position distribution of the infrared points at the same time within the trajectory performance time period and the position changes of the infrared points at different times, thereby improving the accuracy of the motion trajectory acquisition results. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the prior art descriptions. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0043] Figure 1 A flowchart of a method performed by an ear-worn temporomandibular joint movement monitoring system provided by an embodiment of the present invention;

[0044] Figure 2 A schematic diagram of the condyle vector provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, an ear-worn temporomandibular joint movement monitoring system proposed in accordance with the present invention is described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0046] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0047] The specific scheme of the ear-worn temporomandibular joint movement monitoring system provided by the present invention is described in detail below with reference to the accompanying drawings.

[0048] An embodiment of an ear-worn temporomandibular joint motion monitoring system:

[0049] The specific scenario targeted by this embodiment is: in the process of monitoring the movement of the temporomandibular joint of the monitored person, the monitored person is given an ear-worn temporomandibular joint movement monitoring device to collect information on infrared points on the face of the monitored person during the monitoring period, and the accurate condylar movement trajectory is obtained by analyzing and processing the collected information.

[0050] This embodiment proposes an ear-worn temporomandibular joint motion monitoring system, which includes a memory and a processor. The processor executes a computer program stored in the memory to implement the following Figure 1 The specific steps are as follows:

[0051] Step S1: using an ear-worn temporomandibular joint movement monitoring device to obtain infrared points on the face of a person to be monitored and a modulus value of each infrared point within a monitoring period.

[0052] Currently, when monitoring the movement of the temporomandibular joint of the monitored person, the movement trajectory of the patient's hip bone when opening and closing the mouth is mainly monitored, and the movement trajectory is then analyzed and judged. However, in this process, CT or MRI equipment is needed to detect the monitored person. During the examination, the monitored person is required to move the mandible according to a specific movement method. The detection has great limitations. For example, the abnormal jaw joint movement of the monitored person causes different chewing habits on both sides, resulting in asymmetric temporomandibular joint disorder on both sides. During the detection, the symptoms are not accurate enough due to the uniform force on both sides. However, professional detection equipment such as CT equipment and MRI equipment are too large to realize the daily hip movement trajectory monitoring of the monitored person.

[0053] In this embodiment, the person to be monitored is first monitored using an ear-worn temporomandibular joint motion monitoring device. Specifically, the person to be monitored wears the ear-worn temporomandibular joint motion monitoring device, which includes an ear-hanging assembly and a scanning module. The scanning module is hung on the ear through the ear-hanging assembly. The scanning module is located below the earlobe. The scanning module is divided into an infrared camera and an infrared unit dot matrix projector. The infrared unit dot matrix projector projects onto the face, and the infrared camera collects the facial dot matrix to realize the collection of feature points of the human face. In this embodiment, the infrared dot matrix projector projects a number of infrared dots onto the face of the person to be monitored during the monitoring period, and the distance from the infrared camera to the infrared dot is used as the modulus value of the infrared dot. In this embodiment, the projection frequency of the infrared dot is once every 0.05 seconds. The duration of the monitoring period is set by the implementer according to the specific situation, and will not be elaborated here.

[0054] At this point, the infrared points of the face of the monitored person at each moment during the monitoring period and the modulus value of each infrared point are collected.

[0055] Step S2, correcting the module values ​​of the infrared points on both sides of the face according to the turning direction and acceleration of the face during the monitoring period to obtain the corrected module values; determining the motion law value corresponding to each infrared point at each moment according to the fluctuation of the corrected module values ​​of all infrared points in the time neighborhood of each infrared point.

[0056] Portable devices cannot directly observe the movement trajectory of the condyle through human tissue. It is necessary to keep the shape of the mandible of the monitored person unchanged and quantify the overall movement trajectory of the mandible to obtain the movement trajectory of the condyle. Therefore, it is necessary to first obtain the patient's mandibular modeling.

[0057] The human skeleton does not move with muscle movement. For the human mandible, the skin and tissue at the jawline are thinner than other areas of the bone, and their thickness does not change significantly during movement. Therefore, the jawlines on both sides of the mandible serve as the left and right baselines of the mandible. After modeling the mandible of the monitored individual, when the mandible moves, the baselines will move in space, while the position of the condyle relative to the jawline is relatively fixed. Therefore, once the movement trajectory of the jawline is determined, the movement trajectory of the condyle can be determined.

[0058] Since patients move around in their daily lives, they are more susceptible to the influence of the external environment than when they are stationary and open and close their mouths during a specific examination. Therefore, this embodiment installs an accelerometer in the portable device, and uses the accelerometer to collect the rotation direction and acceleration of the head at each moment, and analyzes the movement of the mandibular joint of the monitored person's face, so as to adjust the collected infrared point information to eliminate interference.

[0059] When the monitored person's head rotates, the ear-worn device attached to the ear rotates with it, causing relative displacement between the device facing away from the rotation direction and the face. However, the device facing the rotation direction, being in close contact with the face, does not move. This results in a significant deviation in the overall modulus of the infrared spot information collected on one side. Furthermore, the greater the acceleration of the angular velocity, the greater the deviation in the modulus of the infrared spot information on the side facing away from the rotation. As rotation gradually stops, the acceleration of the angular velocity becomes negative, causing inertia to cause displacement of the device facing the rotation direction, leading to a deviation in the modulus. The device facing away from the face is in close contact with the face, and the infrared spot information on the side facing away from the rotation is more accurate.

[0060] Based on the above features, this embodiment will be described below using a moment in the monitoring period as an example. The method provided in this embodiment can be used to process other moments in the monitoring period.

[0061] For any moment during the monitoring period:

[0062] If the person to be monitored turns his head at this moment, the side of the person to be monitored that is closer to the ear-worn temporomandibular joint motion monitoring device is recorded as the first side, and the other side other than the first side is recorded as the second side. If the steering acceleration at this moment is less than 0, the difference between the constant 1 and the normalized value of the steering acceleration at this moment is recorded as the first difference, the product of the first difference and the modulus value of each infrared point on the first side is used as the corrected modulus value of each infrared point on the first side, and the modulus value of each infrared point on the second side is used as the corrected modulus value of each infrared point on the second side. If the steering acceleration at this moment is greater than or equal to 0, the difference between the constant 1 and the normalized value of the steering acceleration at this moment is recorded as the second difference, the product of the second difference and the modulus value of each infrared point on the second side is used as the corrected modulus value of each infrared point on the second side, and the modulus value of each infrared point on the first side is used as the corrected modulus value. It should be noted that if the person to be monitored does not turn his head, the initially collected modulus value is used as the corrected modulus value.

[0063] In this embodiment, the calculation formula of the modified modulus value is given, which is specifically expressed as:

[0064]

[0065]

[0066] in, It represents the corrected modulus value of the ith infrared point on the first side of the face of the monitored person at the tth moment within the monitoring period. It represents the corrected modulus value of the jth infrared point on the second side of the face of the monitored person at the tth moment within the monitoring period. represents the turning acceleration of the face at the tth moment during the monitoring period, It represents the modulus value of the ith infrared point on the first side of the face of the monitored person at the tth moment within the monitoring period, It represents the modulus value of the j-th infrared point on the second side of the face of the monitored person at the t-th moment within the monitoring time period.

[0067] when hour, Indicates the first difference; when hour, Represents the second difference. When the acceleration is positive, the device in the first direction is pressed against the face, while the device in the second direction is thrown away due to inertia. Conversely, when the acceleration is negative, the opposite occurs. Therefore, the modulus values ​​of the infrared points on the left and right sides of the face at time t are corrected using the acceleration.

[0068] When analyzing a patient's condition through temporomandibular joint movement, it is necessary to collect targeted trajectory information to achieve an in-depth understanding of the specific conditions of the temporomandibular joint of the monitored person. Therefore, the obtained trajectory information must be close to the daily life of the monitored person and cannot contain much interference. The opening and closing of the monitored person's mouth is mainly due to the lower jaw chewing, talking, yawning, etc. In order to obtain the data segments containing information, it is necessary to screen the jaw joint information on both sides.

[0069] Since the mandible of the monitored person is relatively fixed when opening and closing the mouth, the opening and closing angles on both sides are often the same or similar. Therefore, the closer the modulus changes of the infrared points on both sides are in continuous time, the better, and the amplitude of the change is periodic within a certain period of time. The higher the consistency between the two sides, the more conducive it is to judge the patient's mandibular movement through continuous trajectory analysis.

[0070] For any moment during the monitoring period:

[0071] Taking the moment as the starting moment, a preset number of moments are obtained in chronological order, and these moments are used as moments in the time neighborhood of the moment. In this embodiment, the preset number is 100. In specific applications, the implementer can set it according to specific circumstances.

[0072] A fitting curve is obtained by performing curve fitting on the corrected modulus values ​​of all candidate infrared points within the temporal neighborhood of the moment. This fitting curve is recorded as the fitting curve corresponding to the candidate infrared point at the moment. The time intervals between adjacent extreme value points on the fitting curve are obtained. Based on the time intervals between adjacent extreme value points, the degree of dispersion of the time intervals of all adjacent extreme value points is calculated. Based on the degree of dispersion of the amplitudes of all extreme value points on the fitting curve and the degree of dispersion of all time intervals, the motion law value corresponding to the candidate infrared point at the moment is obtained. The degree of dispersion of the amplitudes and the degree of dispersion of the time intervals are both negatively correlated with the motion law value.

[0073] Among them, the negative correlation relationship means that the dependent variable will decrease as the independent variable increases, and the dependent variable will increase as the independent variable decreases. It can be a subtraction relationship, a division relationship, etc., which is determined by actual application.

[0074] In this embodiment, the variance is used to represent the degree of dispersion.

[0075] In this embodiment, a specific calculation formula for the motion law value is given. The motion law value corresponding to the i-th infrared point at the t-th moment is:

[0076]

[0077] in, Indicates the motion law value corresponding to the i-th infrared point at the t-th moment, It represents the variance of the amplitudes of all extreme points on the fitting curve corresponding to the i-th infrared point at the t-th moment. It represents the variance of the time intervals of all adjacent extreme points on the fitting curve corresponding to the i-th infrared point at the t-th moment, Indicates the preset first adjustment parameter.

[0078] The introduction of a preset first adjustment parameter into the calculation formula for the motion regularity value is intended to prevent the denominator from being zero. In this embodiment, the preset first adjustment parameter is 0.01. In specific applications, the implementer may set this parameter based on specific circumstances. A greater variance in the amplitudes of all extreme points on the fitting curve corresponding to the i-th infrared point at time t indicates a more discrete amplitude distribution of the extreme points. A greater variance in the time intervals between all adjacent extreme points on the fitting curve corresponding to the i-th infrared point at time t indicates a more uneven time interval between extreme points on the fitting curve, i.e., a greater degree of dispersion. When the degree of dispersion of the amplitudes of all extreme points on the fitting curve corresponding to the i-th infrared point at time t and the degree of dispersion of the time intervals between all adjacent extreme points on the fitting curve corresponding to the i-th infrared point at time t are greater, the motion regularity corresponding to the i-th infrared point at time t is lower, i.e., the motion regularity value corresponding to the i-th infrared point at time t is smaller.

[0079] By adopting the above method, the motion law value corresponding to each infrared point at each moment can be obtained.

[0080] Step S3: Determine the confidence level of the weakened side and each infrared point on the weakened side at each moment based on the difference between the overall distribution of the corrected modulus values ​​of the infrared points in the time neighborhood of the infrared points on both sides of the face and the corrected modulus values ​​of the infrared points at corresponding positions on both sides of the face; and select the trajectory expression time period by comprehensively considering the corrected modulus value distribution, motion regularity value, and confidence level of the infrared points in the time neighborhood of the infrared points on the weakened side.

[0081] Because facial muscles shift during facial movement, causing some infrared points to shift position, the facial muscles on the left and right sides of the face are roughly consistent. Therefore, the confidence level of the movement regularity of each infrared point can be determined by analyzing the changes in the modulus curves of corresponding infrared points on both sides. However, considering that chewing often involves inconsistent force on both sides, for example, when chewing only on one side, the amount and hardness of food chewed in a short period of time on both sides may not be exactly the same. Therefore, it is necessary to derive a reduction coefficient based on the overall modulus difference of all infrared points on both sides to reduce the impact of unilateral chewing on the infrared point modulus length.

[0082] For any moment during the monitoring period:

[0083] Calculate the average modulus of all infrared points on each side of the monitored person's face at that moment; the side with the largest average modulus is considered the weakened side. The ratio of the average modulus of all infrared points on the other side (excluding the weakened side) to the average modulus of all infrared points on the weakened side is used as the weakening coefficient of the weakened side at that moment.

[0084] Next, we will use any infrared point on the weakened side as an example to illustrate. The method provided in this embodiment can be used to process other infrared points on the weakened side. Specifically, any infrared point on the weakened side is recorded as the infrared point to be analyzed. The product of the corrected modulus value of the infrared point to be analyzed at each moment in the time neighborhood of that moment and the weakening coefficient of the weakened side at that moment is recorded as the first product corresponding to each moment in the time neighborhood. The difference between the first product corresponding to each moment in the time neighborhood and the corrected modulus value of the infrared point at the position corresponding to the infrared point to be analyzed on the other side of the time neighborhood, excluding the weakened side, at the same moment is calculated. Based on the difference between the modulus values, the confidence level of the infrared point to be analyzed at that moment is obtained. The difference between the modulus values ​​is negatively correlated with the confidence level.

[0085] In this embodiment, a specific calculation formula for the confidence level is given. The confidence level of the k-th infrared point on the weakened side at the t-th time can be expressed as:

[0086]

[0087] in, represents the confidence of the kth infrared point on the weakened side at the tth moment, represents the number of moments in the time neighborhood of the t-th moment, represents the corrected modulus value of the kth infrared point on the weakened side at the uth moment in the time neighborhood at the tth moment, represents the weakening coefficient of the weakened side at the tth moment, It represents the corrected modulus value of the kth infrared point on the other side except the weakened side at the uth moment in the time neighborhood of the tth moment, Indicates the preset second adjustment parameter.

[0088] The purpose of introducing the preset second adjustment parameter into the calculation formula of the motion law value is to prevent the denominator from being 0. In specific applications, the implementer can set it according to the specific situation, and no further details will be given here. It represents the residual value between the modulus value of the infrared point to be analyzed in the time neighborhood at the t-th moment after being weakened and the modulus value of the infrared point at the corresponding position on the other side except the weakened side. The smaller the residual value is, the more consistent the two sides are. It also means that the point can better show the movement consistency of the two sides, that is, the point can show the information of the mandibular movement process, and the higher the confidence of the point is.

[0089] When the face moves, in addition to regular movements, there are also large mouth openings such as yawning. Due to the disorder of the masticatory muscles or joint structure, the condyle moves forward excessively when the mouth is opened widely. There are also hidden dangers of mandibular dislocation caused by excessive mandibular movement, iatrogenic external force and loosening of the joint capsule ligaments. Therefore, it is also necessary to determine whether there is a large movement at the tth moment. These large mouth openings are also of great significance for monitoring the movement of the mandible.

[0090] Based on the above characteristics, for any moment within the monitoring time period: the difference between the maximum value and the second maximum value on the fitting curve corresponding to the infrared point to be analyzed is used as the motion performance of the infrared point to be analyzed at that moment; the normalized result of the product of the confidence and the motion regularity value of each infrared point on the weakened side at that moment is calculated respectively, and the maximum value of the normalized result and the normalized value of the motion performance of each infrared point on the weakened side at that moment is used as the characteristic value of each infrared point; the average value of the characteristic values ​​of all infrared points at that moment is used as the preferred index at that moment.

[0091] In this embodiment, a specific calculation formula for the preference index is given. The preference index at the t-th moment can be expressed as:

[0092]

[0093] in, represents the optimal index at the tth moment, represents the number of infrared points at the tth moment, represents the confidence of the kth infrared point on the weakened side at the tth moment, Indicates the motion law value of the kth infrared point on the weakened side at the tth moment, It represents the motion performance of the kth infrared point on the weakened side at the tth moment, represents the normalization function, Represents the maximum value function.

[0094] Since the infrared unit dot matrix projectors on both sides are the same, the number of points projected onto the face is consistent. Therefore, this embodiment takes the weakened side as an example for analysis to obtain the optimal index at the tth moment, and then obtains the optimal index at all moments.

[0095] The time period consisting of adjacent moments where the preference index is greater than the preset preference threshold is used as the trajectory representation time period. In this embodiment, the preset preference threshold is 0.68. In specific applications, the implementer can set it according to the amount of collected data.

[0096] So far, the trajectory performance time period has been screened out from the monitoring time period using the above method.

[0097] Step S4, determining the condylar motion trajectory of the person to be monitored based on the relative position distribution of the infrared points at the same time and the position changes of the infrared points at different times within the trajectory representation time period.

[0098] In step S3, this embodiment selects the trajectory performance time period. Next, the condylar motion trajectory of the monitored person is determined based on the relative position distribution of the infrared points at the same time within the trajectory performance time period and the position changes of the infrared points at different times.

[0099] Specifically, for any moment within the trajectory performance time period: the vector pointed by the infrared camera to each infrared point is used as the vector of each infrared point, and the modulus of the vector is the distance between the infrared camera and the infrared point. The jaw line is obtained based on the position distribution of the infrared points at that moment. The jaw line position is also the outermost edge of the chin of the person to be monitored that can be observed by the scanning module; for each side of the face of the person to be monitored: the lowest point in the jaw line is used as the starting point, and the interception point of the line segment of the preset first length on the jaw line is used as the starting point of the condyle vector, and a vector of the preset second length and the angle between the vector and the jaw line is a preset angle is obtained as the condyle vector; the position of the end point of the condyle vector is determined as the position of the condyle feature point; as shown in FIG. Figure 2 As shown in the figure, 1 is the mandibular line, 2 is the interception point, i.e., the starting point of the condyle vector, 3 is the preset angle, and 4 is the condyle vector. In this embodiment, the preset first length is 3 cm, the preset second length is 13 cm, and the preset angle is 36°. In specific applications, the implementer can set it according to specific circumstances.

[0100] By using the above method, the position of the condyle feature point at each moment in the abdominal muscle performance time period can be obtained. According to the position of the condyle feature point at all moments in the trajectory performance time period, the condyle motion trajectory of the monitored person can be obtained.

[0101] Thus, the condyle motion trajectory has been determined using the method provided in this embodiment.

[0102] This embodiment first uses an ear-worn temporomandibular joint motion monitoring device to obtain infrared points on the face of the person to be monitored and the modulus value of each infrared point during the monitoring period. Since the head of the person to be monitored rotates during the monitoring process, the ear-worn device mounted on the ear will rotate accordingly, causing the device on the side facing away from the rotation direction to have a relative displacement with the face, while the device on the side facing the rotation direction does not have a displacement due to being in close contact with the face, resulting in a large deviation in the modulus value of one side of the collected infrared point information. Therefore, the modulus value of the infrared point is corrected in combination with the face's rotation direction and acceleration, and the time neighborhood of each infrared point is used to calculate the modulus value of each infrared point. The fluctuation of the corrected modulus values ​​of all infrared points in the facial area was analyzed, and the movement regularity of each infrared point at each movement moment was evaluated. According to the difference between the overall distribution of the corrected modulus values ​​of the infrared points in the time neighborhood of the infrared points on both sides of the face, and the corrected modulus values ​​of the infrared points at corresponding positions on both sides of the face, the confidence level of each infrared point on the weakened side at each moment was determined. Then, the trajectory performance time period within the monitoring time period was screened out. The movement trajectory of the condyle was determined based on the relative position distribution of the infrared points at the same time within the trajectory performance time period and the position changes of the infrared points at different times, thereby improving the accuracy of the motion trajectory acquisition results.

[0103] In other embodiments, an ear-worn temporomandibular joint motion monitoring device is provided, comprising a memory and a processor. The memory is used to store executable program code, and the processor is used to retrieve and execute the executable program code from the memory, causing the device to execute the method performed by the ear-worn temporomandibular joint motion monitoring system described above. The device can be specifically a chip, component, or module, and the chip may include a connected processor and memory; the memory is used to store instructions, and when the processor retrieves and executes the instructions, the chip can execute the method performed by the ear-worn temporomandibular joint motion monitoring system provided in the above embodiments.

[0104] In other embodiments, a computer program product is also provided. When the computer program product is run on a computer, it enables the computer to execute the above-mentioned related steps to implement the method executed by the ear-worn temporomandibular joint movement monitoring system provided in the above embodiment.

[0105] In other embodiments, a computer-readable storage medium is also provided, which stores computer program code. When the computer program code is run on a computer, the computer executes the above-mentioned related method steps to implement the method performed by the ear-worn temporomandibular joint motion monitoring system provided in the above-mentioned embodiment.

[0106] Among them, the provided devices, computer program products, and computer-readable storage media are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0107] It should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An ear-worn temporomandibular joint motion monitoring system, comprising a memory and a processor, characterized in that: The processor executes the computer program stored in the memory to implement the following steps: Using an ear-worn temporomandibular joint movement monitoring device to obtain infrared points on the face of the monitored person during the monitoring period and the modulus value of each infrared point; The modulus values ​​of the infrared points on both sides of the face are corrected according to the face's rotation and acceleration during the monitoring period to obtain the corrected modulus values; the motion law value corresponding to each infrared point at each moment is determined based on the fluctuation of the corrected modulus values ​​of all infrared points in the time neighborhood of each infrared point; Determine the confidence level of the weakened side and each infrared point on the weakened side at each moment based on the difference between the overall distribution of the corrected modulus values ​​of the infrared points in the time neighborhood of the infrared points on both sides of the face and the corrected modulus values ​​of the infrared points at corresponding positions on both sides of the face; and select the trajectory expression time period based on the distribution of the corrected modulus values ​​of the infrared points in the time neighborhood of the infrared points on the weakened side, the motion regularity value, and the confidence level. Determine the condylar motion trajectory of the monitored person based on the relative position distribution of the infrared points at the same time and the position changes of the infrared points at different times within the trajectory performance time period; Determination of the weakened side, including: For any moment in the monitoring period: calculate the average modulus of all infrared points on each side at any moment; take the side with the largest average modulus as the weakened side; The confidence level of each infrared point on the weakened side at each moment is obtained, including: The ratio of the average modulus value of all infrared points on the other side except the weakened side at any moment to the average modulus value of all infrared points on the weakened side is used as the weakening coefficient of the weakened side at any moment; The product of the corrected modulus value of the infrared point to be analyzed at each moment in the time neighborhood of the any moment and the attenuation coefficient of the weakened side at the any moment is recorded as the first product corresponding to each moment in the time neighborhood; the difference between the first product corresponding to each moment in the time neighborhood and the corrected modulus value of the infrared point at the position corresponding to the infrared point to be analyzed on the other side of the time neighborhood except the weakened side at the same moment in the time neighborhood is calculated; Obtaining the confidence level of the infrared point to be analyzed at any moment according to the difference between the module values, wherein the difference between the module values ​​is negatively correlated with the confidence level; The infrared point to be analyzed is any infrared point on the weakened side.

2. The ear-worn temporomandibular joint motion monitoring system according to claim 1, characterized in that: The method of correcting the modulus values ​​of the infrared points on both sides of the face according to the face's rotation direction and acceleration during the monitoring period to obtain the corrected modulus values ​​includes: For any moment during the monitoring period: If the monitored person turns his head at any moment, the side of the monitored person's face close to the ear-worn temporomandibular joint movement monitoring device is recorded as the first side, and the other side except the first side is recorded as the second side; If the steering acceleration at any moment is less than 0, the difference between the constant 1 and the normalized value of the steering acceleration at any moment is recorded as a first difference, the product of the first difference and the modulus value of each infrared point on the first side is used as the corrected modulus value of each infrared point on the first side, and the modulus value of each infrared point on the second side is used as the corrected modulus value of each infrared point on the second side; If the steering acceleration at any moment is greater than or equal to 0, the difference between the constant 1 and the normalized value of the steering acceleration at any moment is recorded as the second difference, the product of the second difference and the modulus value of each infrared point on the second side is used as the corrected modulus value of each infrared point on the second side, and the modulus value of each infrared point on the first side is used as the corrected modulus value of each infrared point on the first side.

3. The ear-worn temporomandibular joint motion monitoring system according to claim 2, characterized in that: The method of determining the motion law value corresponding to each infrared point at each moment according to the fluctuation of the corrected modulus values ​​of all infrared points in the time neighborhood of each infrared point includes: For any moment during the monitoring period: Performing curve fitting on the corrected modulus values ​​of all candidate infrared points within the time neighborhood at any moment to obtain a fitting curve; According to the discrete degrees of the amplitudes of all extreme value points on the fitting curve and the discrete degrees of the time intervals of all adjacent extreme value points, the motion law value corresponding to the candidate infrared point at any time is obtained, and the discrete degrees of the amplitudes and the discrete degrees of the time intervals are both negatively correlated with the motion law value; The candidate infrared point is any infrared point.

4. The ear-worn temporomandibular joint movement monitoring system according to claim 3, characterized in that: The method of comprehensively analyzing the corrected modulus distribution, motion regularity value, and confidence level of infrared points in the time neighborhood of the weakened side infrared point to screen the trajectory performance time period includes: For any moment within the monitoring period: the difference between the maximum value and the second maximum value on the fitting curve corresponding to the infrared point to be analyzed is used as the movement performance of the infrared point to be analyzed at any moment; Obtaining a preferred index at any moment according to the motion performance, motion regularity value, and confidence level of each infrared point on the weakened side at any moment; Based on the optimal index at each moment in the monitoring period, the trajectory performance period is filtered.

5. The ear-worn temporomandibular joint movement monitoring system according to claim 4, characterized in that: According to the motion performance, motion regularity value and confidence of each infrared point on the weakened side at any moment, the optimal index at any moment is obtained, including: For any moment during the monitoring period: Calculate the normalized result of the product of the confidence and the motion regularity value of each infrared point on the weakened side at any time, and use the maximum value of the normalized result and the normalized value of the motion performance of each infrared point on the weakened side at any time as the characteristic value of each infrared point; The average value of the characteristic values ​​of all infrared points at any moment is used as the preferred index at any moment.

6. The ear-worn temporomandibular joint movement monitoring system according to claim 4, characterized in that: The screening of the trajectory performance time period based on the preference index of each moment in the monitoring time period includes: taking a time period consisting of adjacent moments whose preference index is greater than a preset preference threshold as the trajectory performance time period.

7. The ear-worn temporomandibular joint movement monitoring system according to claim 1, characterized in that: Determining the condylar motion trajectory of the person to be monitored based on the relative position distribution of the infrared points at the same time and the position changes of the infrared points at different times within the trajectory representation time period includes: At any moment within the trajectory representation time period: the vector pointed by the infrared camera to each infrared point is used as the vector of each infrared point; the jaw lines of both sides of the face of the monitored person are obtained respectively; the lowest point of the jaw line is used as the starting point, the interception point of a line segment of a preset first length on the jaw line is used as the starting point of the condyle vector, and a vector of a preset second length and a preset angle with the jaw line is obtained as the condyle vector; the position of the condyle feature point is determined based on the condyle vector; The condyle motion trajectory of the monitored person is obtained according to the positions of the condyle feature points at all times within the trajectory performance time period.

8. The ear-worn temporomandibular joint movement monitoring system according to claim 1, characterized in that: Acquiring the modulus value of the infrared point includes: using the distance from the infrared camera to the infrared point as the modulus value of the infrared point.

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