Glasses hanging rope data correction method for correcting eye using posture

Abstract

The invention provides a glasses hanging rope data correction method for correcting an eye using posture, which comprises the following steps of: 1, facing a horizontal calibration plate, acquiring a first left side distance value and a first right side distance value, calculating a first distance difference value, judging whether the first distance difference value exceeds an error threshold value or not, and if not, determining that the horizontal calibration is successful; if yes, adjusting the positions of the first sampling end and the second sampling end, and circulating the step 1; 2, the vertical calibration plate is horizontally viewed, a second left side distance value and a second right side distance value are obtained, a second distance difference value is calculated, whether the second distance difference value exceeds an error threshold value or not is judged, if not, a plurality of sets of X-axis acceleration data, Y-axis acceleration data and Z-axis acceleration data are obtained, a mean value is calculated to generate a three-axis acceleration value of the reference dip angle, and vertical calibration succeeds; if yes, reminding to adjust the head angle, and circulating the step 2. The installation position of the distance sensor can be accurately calibrated through simple steps, the reference dip angle parameter of the motion sensor can be determined, and the detection accuracy is improved.

Description

Technical Field

[0001] The invention relates to the technical field of sensor calibration, and in particular to a method for correcting glasses hanging rope data for correcting eye posture. Background Art

[0002] In the prior art, a myopia prevention and control device with a glasses hanging rope structure is disclosed, in which a motion sensor and a distance sensor are hung on the left and right sides of the glasses frame. The motion sensor is used to collect the reading inclination data when the user is reading, but due to different people's glasses wearing habits, when looking forward after wearing glasses, the inclination of the motion sensor is different, resulting in low accuracy of the reading inclination data.

[0003] The distance sensors on both sides of the frame are used to obtain the reading distance data of the user on the left and right sides, and judge whether the user has strabismus or the severity of strabismus through the reading distance data on the left and right sides. However, the distance sensors are manually installed on the left and right sides of the frame by the user, and it is difficult to ensure that the distance sensors on both sides are aligned, which affects the judgment of the severity of strabismus. Summary of the invention

[0004] In view of this, the problem to be solved by the present invention is to provide a method for correcting eyeglass strap data for correcting eye posture, which can combine the use of difference factors, accurately calibrate the installation position of the distance sensor through simple steps, and determine the reference inclination parameters of the motion sensor, thereby improving detection accuracy.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A method for correcting eye posture eyeglasses hanging rope data, comprising a first sampling end and a second sampling end fixedly mounted on both sides of a frame, wherein the first sampling end comprises a first distance sensor generating a left distance value, the second sampling end comprises a second distance sensor generating a right distance value, and the first sampling end or the second sampling end comprises a motion sensor for acquiring a tilt angle;

[0007] Correction methods based on the above system include:

[0008] Step 1: look at the first viewpoint on the horizontal calibration board at an angle, obtain the first left distance value and the first right distance value, calculate the difference to generate a first distance difference, and judge whether the first difference exceeds the error threshold. If not, give feedback that the horizontal calibration is successful; if yes, remind to adjust the positions of the first sampling end and the second sampling end, and repeat step 1;

[0009] Step 2: Look horizontally at the second viewpoint on the vertical calibration board, obtain the second left distance value and the second right distance value and calculate the difference to generate a second distance difference, and determine whether the second distance difference exceeds the error threshold. If not, obtain several groups of X-axis acceleration data, Y-axis acceleration data and Z-axis acceleration data and calculate the average to generate three-axis acceleration value data of the reference inclination angle, and give feedback on successful vertical calibration; if yes, remind to adjust the head angle and repeat step 2.

[0010] Furthermore, the user faces the horizontal calibration plate and the vertical calibration plate, and the first viewpoint and the second viewpoint are both located directly in front of the user.

[0011] Furthermore, the straight-line distance between the first viewpoint, the second viewpoint and the mirror frame ranges from 30 cm to 100 cm.

[0012] Furthermore, the motion sensor is a six-axis sensor.

[0013] Furthermore, the method for calculating the reading inclination by the motion sensor is: obtaining the three-axis acceleration value (x1, y1, z1) of the reference inclination, obtaining the three-axis acceleration value (x2, y2, z2) of the current inclination through the motion sensor, and using the formula:

[0014]

[0015] Calculate the reading inclination angle of the user when reading.

[0016] Furthermore, the first distance sensor and the second distance sensor both implement distance measurement based on the dToF principle, and the first distance sensor includes a transmitting end and a receiving end;

[0017] The distance measurement method of the first distance sensor is: within a single frame measurement time, the transmitting end and the receiving end emit and receive light signals N times, and record the N flight times of the light signals, make a histogram with time as the horizontal axis and number of times as the vertical axis, obtain the flight time t with the highest frequency, and calculate the first distance value through the formula S=Ct / 2, where: S is the distance; C is the speed of the laser in the air; t is the time difference between transmitting and receiving the echo.

[0018] Furthermore, the transmitting end transmits an optical signal, the receiving end receives the optical signal, the reftof value corresponds to the intensity of the optical signal, and in order to improve the receiving efficiency of the optical signal, the step 1 includes temperature calibration;

[0019] The temperature calibration includes: obtaining the current reftof value at the current temperature according to the flight time t of the first distance sensor or the second distance sensor, the distance sensor includes the factory reftof value, comparing the current reftof value with the factory reftof value to adjust the optical power of the transmitting end and the power-off voltage gear of the receiving end to improve the performance of the distance sensor.

[0020] The advantages and positive effects of the present invention are:

[0021] By setting the horizontal calibration and vertical calibration to adjust the reference values ​​of the sensor before the user uses the glasses, the distance sensor and motion sensor can be calibrated simply and accurately based on the user's wearing habits, thereby improving the accuracy of the reading distance and reading inclination detection when the user is reading. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0023] Figure 1 It is an overall flow chart of a method for correcting data of glasses hanging ropes for correcting eye posture of the present invention;

[0024] Figure 2 It is a right triangle diagram formed by the first motion data and the second motion data constant temperature vertical calibration plate in the glasses hanging rope data correction method for correcting eye posture of the present invention;

[0025] Figure 3 It is a dToF principle diagram of a glasses hanging rope data correction method for correcting eye posture of the present invention;

[0026] Figure 4 The invention discloses a histogram of a method for correcting data of a glasses hanging rope for correcting eye posture. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0029] The present invention provides a method for correcting eye posture using eyeglasses hanging rope data, wherein the eyeglasses hanging rope structure comprises a first sampling end and a second sampling end attached to the left and right sides of the frame, wherein a first distance sensor is fixedly installed in the first sampling end, and a second distance sensor is fixedly installed in the second sampling end. When a user reads, the first distance sensor and the second distance sensor simultaneously obtain the linear distance of a book or a tablet to generate reading distance data, and judge whether the reading posture is normal or whether the user is squinting based on the reading distance data.

[0030] A motion sensor is fixedly installed in the first sampling end or the second sampling end. One embodiment of the present application is that the motion sensor can be a six-axis sensor and is fixedly installed in the first sampling end. The three-axis inclination angle and three-axis acceleration value when the user is reading can be obtained, and the inclination angle and movement path of the user when reading can be determined through the three-axis inclination angle.

[0031] Glasses need to be worn every day, and long-term use of the distance sensor will affect the accuracy of the device. Or the performance of different devices of the same model is not exactly the same, which will cause the errors of the two distance sensors to be not exactly the same.

[0032] like Figure 2 As shown, in order to improve the accuracy of the reading distance, a distance calibration strategy is included. Taking the calibration process of a single distance sensor as an example: After the user puts on the glasses, he faces a vertical plane (vertical calibration plate), which can be a wall. The position of the frame is adjusted according to the motion sensor to make the frame horizontal, remind the user that the frame is in the first position, and obtain the first distance data and the first motion data. Remind the user to change the vertical angle of the frame, and manually determine that it has reached the second position, and obtain the second distance data and the second motion data.

[0033] The coordinates of the first position are defined as the origin coordinates, and the moving path is determined according to the motion sensor to obtain the coordinates of the second position, which are defined as the end point coordinates. The rotation angle of the frame is determined according to the first motion data and the second motion data, and the first distance data and the second distance data are completed according to the rotation angle, the origin coordinates and the end point coordinates. A right triangle can be formed between the first distance data, the second distance data and the vertical plane.

[0034] Since the rotation angle θ obtained by the motion sensor is accurate, the first distance data and the second distance data obtained by the same distance sensor have the same error value X, and the measurement error of the first distance sensor can be calculated by the cosine theorem. The moving paths of the first distance sensor and the second distance sensor are exactly the same, so the two distance sensors should be calibrated synchronously.

[0035] The specific embodiment is: obtaining the completed first distance data L1, the second distance data L2 and the rotation angle θ, wherein: the accuracy interval of the first distance sensor is [a1.a2], the interval of the rotation angle θ is [0.90], and the cosine calculation formula is:

[0036]

[0037] When there are multiple solutions for X in the above formula, the solution close to the accuracy interval [a1.a2] is taken as the final solution. The error of the first distance sensor is calibrated according to the accuracy interval. The operation is simple and fast, which is convenient for users to calibrate by themselves and improve the accuracy of the distance sensor. The distance sensor can be calibrated at intervals of several months. Before the accuracy calibration, the reference of the motion sensor needs to be reset so that the frame can be adjusted according to the motion sensor data so that the frame can be placed horizontally.

[0038] Due to different wearing habits of glasses among different users, the inclination angle of the frame is different when the user looks straight ahead, which affects the accuracy of the reading inclination angle data. Since the first sampling end and the second sampling end on the left and right sides of the frame are manually installed, the positions collected by the first distance sensor and the second distance sensor are not flush, which affects the consistency between the two sets of reading distance data. In order to avoid affecting the judgment of the user's reading posture, the first distance sensor, the second distance sensor and the motion sensor need to be calibrated.

[0039] like Figure 1 As shown in the figure, the calibration process is:

[0040] Step one, look at the first viewpoint on the horizontal calibration plate at an angle, obtain the first left distance value and the first right distance value and calculate the difference to generate a first distance difference, determine whether the first difference exceeds the error threshold, if not, give feedback on successful horizontal calibration; if yes, remind to adjust the positions of the first sampling end and the second sampling end, and repeat step one.

[0041] During horizontal calibration, the user faces forward and looks at the horizontal calibration board for several seconds, and obtains the first left distance value and the first right distance value through the first distance sensor and the second distance sensor. The viewing position is named the viewpoint, and the straight-line distance between the viewpoint and the user is not fixed, and it only needs to be in front of the user.

[0042] The difference between the first left distance value and the first right distance value is calculated and a first distance difference is generated. It is determined whether the first distance difference is less than the error threshold. If yes, it indicates that the distance sensors on the left and right sides are aligned, and a horizontal calibration completion reminder is given. The glasses hanging rope structure can remind the user through vibration that the calibration is successful. The glasses hanging rope structure includes a Bluetooth module, which is wirelessly connected to the sports terminal (mobile phone) and can also be reminded through radial text on the mobile terminal.

[0043] No, through different vibration frequencies, remind the user to adjust the positions of the first distance sensor and the second distance sensor, and re-acquire the first left distance value and the first right distance value, and make a judgment until the horizontal calibration is successful.

[0044] Step 2: Look horizontally at the second viewpoint on the vertical calibration board, obtain the second left distance value and the second right distance value and calculate the difference to generate a second distance difference, and determine whether the second distance difference exceeds the error threshold. If not, obtain several groups of X-axis acceleration data, Y-axis acceleration data and Z-axis acceleration data and calculate the average to generate a three-axis acceleration value of the reference inclination angle, and give feedback on successful vertical calibration; if yes, remind to adjust the head angle and repeat step 2.

[0045] After the horizontal calibration is successful, it means that the two distance sensors are aligned. Make sure your head does not swing left and right, raise your head and look vertically at the vertical calibration board, stop for a few seconds, and obtain the second left distance value and the second right distance value.

[0046] Calculate the difference between the second left distance value and the second right distance value to generate a second distance difference value, determine whether the second distance difference value exceeds the error threshold, if not, it means that there is no left-right offset of the frame, obtain several sets of X-axis acceleration data, Y-axis acceleration data and Z-axis acceleration data, and calculate the average to generate three-axis acceleration value data of the reference inclination angle. The mobile terminal gives a vertical calibration completion reminder in the form of a text reminder, or the glasses hanging rope structure reminds the user through vibration that the vertical calibration is completed.

[0047] The three-axis acceleration value data of the reference inclination angle indicates that when the user wears the glasses normally and looks straight ahead, the three-axis acceleration value data of the motion sensor is defined as the reference data. Combined with the wearing habits of the user's frame, the reference data of the motion sensor is adjusted to improve the accuracy of the reading inclination angle data. For example, different nose bridge heights result in different frame inclination angles.

[0048] If yes, it means that the user's head has shifted left or right and the vertical calibration has failed. The user is reminded to adjust the synchronization angle position and then re-obtain the second left distance value and the second right distance value and make a judgment.

[0049] The reading inclination calculation method based on the three-axis acceleration value data of the reference inclination is: obtain the three-axis acceleration value (x1, y1, z1) of the reference inclination, obtain the three-axis acceleration value (x2, y2, z2) of the current inclination through the motion sensor, and use the formula:

[0050]

[0051] Calculate the reading angle when the user is reading. Reading angles above 180 degrees require additional calculation of flipping, because wearable devices cannot flip more than 180 degrees when worn. To simplify the calculation, only applications with a reading angle of 0-180 degrees are considered.

[0052] Before calibrating the sensor, it is necessary to determine a horizontal calibration plate and a vertical calibration plate. The horizontal calibration plate can be a desktop, and the vertical calibration plate can be against a wall. An embodiment of the present application is that the vertical calibration plate can be a flat wall or a computer screen.

[0053] like Figure 3 and Figure 4 As shown, both the first distance sensor and the second distance sensor realize ranging based on the dToF principle, and the first distance sensor includes a transmitter and a receiver. Take the ranging process of the first distance sensor as an example: the transmitter sends out a light signal, and the receiver receives the light signal. Within the single-frame measurement time, the light signal is continuously sent and received N times, and the time of sending and receiving the light signal is obtained to calculate the flight time t of the N light signals. According to the flight time t and the number N of the light signal, a histogram is constructed with the flight time t as the horizontal axis and the number as the vertical axis. According to the histogram, the flight time t with the highest frequency is obtained, and the first distance value is calculated by the formula S=Ct / 2, where: S is the distance; C is the speed of the laser in the air; t is the time difference between the emission and reception of the echo.

[0054] The transmitter sends out a light signal, and the receiver collects the light signal. Due to the different operating temperatures of the distance sensor, the power-off voltage detection at the receiver is inaccurate, which affects the collection of the light signal. The reftof value corresponds to the intensity of the light signal received by the receiver. In order to improve the receiving efficiency of the light signal, the temperature calibration is set in step 1;

[0055] Temperature calibration includes: obtaining the current reftof value at the current temperature based on the flight time t of the first distance sensor or the second distance sensor, the distance sensor includes the factory reftof value tested during the factory test, comparing the current reftof value with the factory reftof value, and adjusting the optical power of the transmitting end and the power-off voltage position of the receiving end based on the ratio to improve the performance of the distance sensor.

[0056] During calibration, the user faces the horizontal calibration plate and the vertical calibration plate. Determine by visual inspection that the linear distance between the frame and the horizontal calibration plate and the vertical calibration plate is between 30cm and 100cm. Avoid a distance that is too short, which will result in a too short flight time t and affect the calibration of the first distance sensor and the second distance sensor.

[0057] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of this patent.

Claims

1. A method for correcting eyeglass strap data for correcting eye posture, characterized in that: It includes a first sampling end and a second sampling end fixedly mounted on both sides of the frame, the first sampling end includes a first distance sensor that generates a left distance value, the second sampling end includes a second distance sensor that generates a right distance value, and the first sampling end or the second sampling end includes a motion sensor that obtains acceleration data; Correction methods based on the above system include: Step 1: calibrate the installation positions of the first sampling end and the second sampling end, look down at the first viewpoint on the horizontal calibration plate, obtain the first left distance value and the first right distance value and calculate the difference to generate a first distance difference, and determine whether the first difference exceeds the error threshold. If not, give feedback that the horizontal calibration is successful; if yes, remind to adjust the positions of the first sampling end and the second sampling end, and repeat step 1; Step 2, calibrate the horizontal reference value of the motion sensor, look horizontally at the second viewpoint on the vertical calibration board, obtain the second left distance value and the second right distance value and calculate the difference to generate a second distance difference, and determine whether the second distance difference exceeds the error threshold. If not, obtain several groups of X-axis acceleration data, Y-axis acceleration data and Z-axis acceleration data and calculate the average to generate a three-axis acceleration value of the reference inclination angle, and give feedback on successful vertical calibration; if yes, remind to adjust the head angle and repeat step 2.

2. The method for correcting eye posture using eyeglasses strap data according to claim 1, characterized in that: The user faces the horizontal calibration plate and the vertical calibration plate, the first viewpoint is located directly in front of the user, and the second viewpoint is located directly in front of the user's face.

3. The method for correcting eye posture using eyeglasses strap data according to claim 2, characterized in that: The straight-line distance between the first viewpoint, the second viewpoint and the mirror frame ranges from 30cm to 100cm.

4. The method for correcting eyeglass strap data for correcting eye posture according to claim 1, characterized in that: The motion sensor is a six-axis sensor.

5. The method for correcting eye posture using eyeglasses strap data according to claim 1, characterized in that: The calculation method of the reading inclination data is: obtain the three-axis acceleration value (x1, y1, z1) of the reference inclination, obtain the three-axis acceleration value (x2, y2, z2) of the current inclination through the motion sensor, and use the formula: Calculate the reading inclination angle of the user when reading.

6. The method for correcting eyeglass strap data for correcting eye posture according to claim 1, characterized in that: The first distance sensor and the second distance sensor both implement distance measurement based on the dToF principle, and the first distance sensor includes a transmitting end and a receiving end; The distance measurement method of the first distance sensor is: within a single frame measurement time, the transmitting end and the receiving end transmit and receive light signals N times, and record the flight time of the light signals N times, make a histogram with time as the horizontal axis and number of times as the vertical axis, obtain the flight time t with the highest frequency, and calculate the first distance value through the formula S=Ct / 2, where: S is the distance; C is the speed of the laser in the air; t is the time difference between transmitting and receiving the echo.

7. The method for correcting eyeglass strap data for correcting eye posture according to claim 6, characterized in that: The transmitting end transmits an optical signal, the receiving end receives the optical signal, the reftof value corresponds to the intensity of the optical signal, and in order to improve the receiving efficiency of the optical signal, the step 1 includes temperature calibration; The temperature calibration includes: obtaining the current reftof value at the current temperature according to the flight time t of the first distance sensor or the second distance sensor, the distance sensor includes the factory reftof value, comparing the current reftof value with the factory reftof value to adjust the optical power of the transmitting end and the power-off voltage gear of the receiving end to improve the performance of the distance sensor.

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