An intelligent learning desk with a posture correction function

Abstract

The present invention belongs to the field of household equipment, and particularly relates to an intelligent study desk with a posture correction function; it includes: a desk and chair body, a lamp, a camera, an alarm, and a device manager. Among them, the lamp includes a lamp holder, a lighting source, and a projection lamp. The camera is respectively used to obtain the user's facial image and the user's hand image. The device manager includes a control module and a data processing module. The control module is electrically connected to the projection lamp, the lighting source, and the alarm; the data processing module is electrically connected to the camera, and the data processing module includes an information collection unit, a storage unit, a first judgment unit, a second judgment unit, and a third judgment unit. The first judgment unit is used to judge whether the user's sitting posture is abnormal. The second judgment unit is used to judge whether the user's pen-holding posture is abnormal. The third judgment unit is used to judge whether the user's writing posture is abnormal. The present invention solves the problems that it is difficult to detect, supervise, and correct the sitting posture and writing posture of users during the writing process.

Description

Technical Field

[0001] The present invention belongs to the field of household equipment, and particularly relates to an intelligent study desk with a posture correction function. Background Art

[0002] Students are usually in a critical period of growth and development. Especially for the vast majority of children and adolescents, sitting postures and writing postures during the writing process have an important impact on students' growth and development. In addition, good writing postures also help students improve the comfort of writing and learning efficiency, and enhance the beauty of the fonts written by students and their calligraphy levels.

[0003] In order to help adolescent students develop good sitting posture habits, many parents will specifically purchase study desks with adjustable seat and desk heights for their children to automatically adjust the heights of the desks and chairs according to the students' heights. However, adjustable desks and chairs can only play an auxiliary role and belong to a passive sitting posture correction tool. Such desks and chairs cannot detect and supervise the actual sitting postures and writing postures of students, so it is difficult to effectively achieve the required posture correction effect.

[0004] In response to the above problems, some manufacturers of intelligent study desks have also been constantly innovating and developing products with sitting posture monitoring functions. For example, some study desks developed by certain manufacturers can judge whether the user's sitting posture is normal by sensing the weights of the seat and the backrest. Such adaptive backrest chairs can detect behaviors such as lying on the desk during the user's use, reducing the risk of hunchback caused by improper sitting postures. However, currently, almost all solutions can only detect the user's sitting posture and cannot comprehensively supervise the user's writing posture. If the user has a correct sitting posture but an abnormal writing posture, this will still cause strain on the user's shoulders, waist, arms, etc., and affect the user's writing effect and learning efficiency. Summary of the Invention

[0005] In order to solve the problem that the prior art cannot comprehensively detect the sitting postures and writing postures of users during the writing process, and thus cannot exert effective supervision and correction effects, the present invention provides an intelligent study desk with a posture correction function.

[0006] The present invention is implemented by the following technical solutions:

[0007] An intelligent study desk with a posture correction function, comprising: a desk and chair body, a lamp, at least two groups of cameras, an alarm, and a device manager.

[0008] Among them, the table and chair body includes a table with a horizontal tabletop and a chair. The lamp includes a lamp stand, a lighting source, and a projection lamp. The projection lamp is used to generate guiding information for installing and adjusting the lamp stand on the tabletop. The lamp stand includes a plurality of movable joints and has functions of lifting, rotating, and pitching adjustment. Cameras are respectively installed on the brackets of the lamp; two groups of cameras are respectively used to obtain user facial images and user hand images. The alarm is used to send a posture correction prompt message when receiving any one of the abnormal information.

[0009] The device manager includes a control module and a data processing module. The control module is electrically connected to the projection lamp, the lighting source, and the alarm; the data processing module is electrically connected to the cameras, and the data processing module includes an information acquisition unit, a storage unit, a first judgment unit, a second judgment unit, and a third judgment unit. The information acquisition unit is used to obtain the physiological characteristic data of the user. The storage unit stores a best writing area distribution mapping table and a parameter set of a reasonable writing projection area. The first judgment unit is used to obtain the user facial image collected by the camera, identify and calculate the spatial positions of both eyes; then judge whether the user's sitting posture is abnormal according to whether the relative position between the user's both eyes and the tabletop meets the specification. The second judgment unit is used to obtain the user hand image collected by the camera, identify and calculate the landing position of the pen tip held by the user on the tabletop; then query the best writing area distribution mapping table to obtain the best writing area of the current user; finally judge whether the user's pen-holding posture is abnormal according to whether the real landing position is located in the best writing area. The third judgment unit is used to obtain the user hand image collected by the camera, identify and calculate the spatial position of the pen rod held by the user; then calculate the projection position of the pen rod on the tabletop when the human eye is used as the light source; finally judge whether the projection position of the pen rod is located in the reasonable writing projection area, and further judge whether the user's writing posture is abnormal. The abnormal results generated by the first judgment unit, the second judgment unit, and the third judgment unit are sent to the control module.

[0010] In the present invention, the information acquisition unit requires that the input physiological characteristic data of the user includes at least: age, gender, height, weight, and dominant hand.

[0011] Among them, the second judgment unit judges the distribution direction of the best writing area relative to the human eye according to the information of the dominant hand obtained: when the current user is left-handed, the best writing area is located in the designated area on the left side relative to the human eye; when the current user is right-handed, the best writing area is located in the designated area on the right side relative to the human eye.

[0012] The optimal writing area is used to characterize the allowable range of the pen tip landing point when the current user writes on the desktop in a normal posture; among them, the user's body type is characterized by combining height and BMI index; for two users with the same body type but different dominant hands, the distribution positions of their corresponding optimal writing areas on the desktop are symmetric.

[0013] As a further improvement of the present invention, the distribution range of the optimal writing area corresponding to users with different body types is established in the optimal writing area distribution mapping table. The optimal writing area is rectangular; the data format of the optimal writing area distribution mapping table is defined as: {type, α, L, H}; where, type represents the body type category of the current user; α represents the horizontal angle of the optimal writing area relative to the position of the human eye; L represents the length of the optimal writing area along the length direction of the desktop; H represents the length of the optimal writing area along the width direction of the desktop.

[0014] As a further improvement of the present invention, the judgment process of the third judgment unit is as follows:

[0015] (1) Calculate the central position E0 of the human eye, the pen tip position P, and any point position Q' on the pen barrel.

[0016] (2) Determine the vector of the pen barrel as Furthermore, when the central position E0 of the human eye is used as the light source, calculate the vector corresponding to the projection of the pen barrel on the desktop

[0017] (3) Query the parameter set of the reasonable writing projection area, and determine that the boundary vectors of the reasonable writing projection area are respectively and

[0018] (4) Define the Z-axis direction vector of the space above the desktop as e z , calculate the vector mixed product and the vector mixed product values, and make the following judgments and decisions:

[0019] When both are greater than 0, it is determined that the pen barrel projection PQ is distributed in the reasonable writing projection area, and the current writing posture of the user is normal; otherwise, it is determined that the pen barrel projection PQ exceeds the reasonable writing projection area, and the current writing posture of the user is abnormal.

[0020] As a further improvement of the present invention, the criterion for the first judgment unit to judge that the user's sitting posture is normal is to simultaneously meet the following two conditions:

[0021] (1) The average height value of the user's eyes from the rectangular desktop plane is within the preset height range;

[0022] (2) The included angle between the spatial connection line of the user's two eyes and the long side of the rectangular tabletop is within a preset angle range.

[0023] In a more optimized solution of the present invention, pressure sensors are provided at the positions of the chair, the seat cushion and the backrest; the pressure sensors are communicatively connected to the data processing module and send pressure detection signals thereto. At this time, the criteria for the first judgment unit to judge that the user's sitting posture is normal are that the following four conditions are simultaneously satisfied:

[0024] (1) The average height value of the user's two eyes from the plane of the rectangular tabletop is within a preset height range;

[0025] (2) The included angle between the spatial connection line of the user's two eyes and the long side of the rectangular tabletop is within a preset angle range;

[0026] (3) The fluctuation of the pressure signal at the seat cushion is within a preset amplitude;

[0027] (4) The fluctuation of the pressure signal at the backrest is within a preset amplitude.

[0028] As a further improvement of the present invention, the lamp holder includes a vertical frame, a horizontal frame and a connecting frame. The bottom of the vertical frame is fixedly connected to the table, and the top is movably connected to one end of the connecting frame through a hinge I. One end of the horizontal frame is movably connected to the other end of the connecting frame through a hinge II. The hinge I and the hinge II enable the horizontal frame to be adjusted in pitch relative to the vertical frame. The vertical frame adopts a two-section structure, and at least one section adopts a telescopic frame. The two sections of the vertical frame are connected by a joint I and enable the two to rotate coaxially relative to each other. The horizontal frame also adopts a two-section structure, and the two sections of the horizontal frame are connected by a joint II and enable the two to rotate coaxially relative to each other.

[0029] In the intelligent learning table with a posture correction function provided by the present invention, the lighting source, the projection lamp and the camera are respectively installed at different positions on the horizontal frame.

[0030] As a further improvement of the present invention, the process of installing and debugging the lamps by using the projection lamp is as follows:

[0031] 1. When the projection lamp is turned on, a pattern for representing the area range meeting the lighting requirements is generated below.

[0032] 2. Adjust the connection states of the horizontal frame, the vertical frame and the connecting frame in the lamp holder so that the pattern generated by the projection lamp coincides with a specified area on the tabletop below.

[0033] 3. After the above adjustments are completed, fix the states of the hinge I, the hinge II, the joint I and the joint II in the lamp holder. At this time, the specified areas on the tabletop below all meet the lighting requirements after the lighting source is turned on.

[0034] As a further improvement of the present invention, the camera adopts a depth camera or a multi-camera; when the first judgment unit and the second judgment unit in the data processing module fail to detect a face and a hand image within a preset period; the control module automatically turns off the lighting source.

[0035] As a further improvement of the present invention, the device manager further includes a communication unit, which is used to communicate with other devices to perform data transmission between other devices and the device manager; the other devices send physiological feature data input by the user to the device manager.

[0036] The technical solution provided by the present invention has the following beneficial effects:

[0037] The intelligent learning desk provided by the present invention is equipped with a camera in the lamp and has a built-in device manager. The device manager can analyze the sitting posture, pen-holding posture and writing posture of the user by using the image information collected by the camera, and combine the relevant sample data collected in advance by itself to judge whether the sitting posture, pen-holding posture and writing posture of the user are normal.

[0038] The intelligent learning desk of the present invention can supervise the user's posture throughout the use process, and issue a warning in time when the posture is abnormal during the user's writing process, helping the user correct the abnormal writing posture, which has a positive effect on improving the user's learning efficiency, improving the user's calligraphy skills, and protecting the user from labor injuries.

[0039] The intelligent learning desk is also provided with a projection lamp for guiding the adjustment of the lamp holder. With the projection lamp, the user can very intuitively adjust the lighting effect of the lamp, ensuring that the user can be in the best light state during the learning process; avoiding damage to the user's eyes caused by poor lighting effect of the lamp. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The 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 to the present invention. In the drawings:

[0041] Figure 1 It is a step flow chart of a writing posture supervision method provided in Embodiment 1 of the present invention.

[0042] Figure 2 It is a schematic diagram of the spatial position of the writing plane on the desktop in Embodiment 1 of the present invention.

[0043] Figure 3 It is a schematic diagram of the spatial position of the best writing area on the desktop in Embodiment 1 of the present invention.

[0044] Figure 4It is a flowchart of the steps of the method for dividing the optimal writing area in Embodiment 1 of the present invention.

[0045] Figure 5 It is a schematic diagram of the state where the pen tip of the user is located within the optimal writing area in Embodiment 1 of the present invention.

[0046] Figure 6 It is a schematic diagram of the state where the pen tip of the user is located outside the optimal writing area in Embodiment 1 of the present invention.

[0047] Figure 7 It is a spatial layout diagram of the writing frame, the writing plane, and the optimal writing area in Embodiment 1 of the present invention.

[0048] Figure 8 It is a flowchart of the steps of the writing frame generation process in Embodiment 1 of the present invention.

[0049] Figure 9 It is a schematic diagram of the state where the projection position of the pen barrel is located within the reasonable projection area in Embodiment 1 of the present invention.

[0050] Figure 10 It is a schematic diagram of the state where the projection position of the pen barrel is located outside the reasonable projection area in Embodiment 1 of the present invention.

[0051] Figure 11 It is a flowchart of the steps of the generation process of the reasonable projection area for writing in Embodiment 1 of the present invention.

[0052] Figure 12 It is a flowchart of the steps of determining whether the writing posture of the user is abnormal according to the projection vector of the pen barrel in Embodiment 1 of the present invention.

[0053] Figure 13 It is a schematic structural diagram of an intelligent learning desk with a posture correction function provided in Embodiment 2 of the present invention.

[0054] Figure 14 It is a schematic structural diagram of the lamp holder part in the intelligent learning desk of Embodiment 2 of the present invention.

[0055] Figure 15 It is a module block diagram of the control part in the intelligent learning desk of Embodiment 2 of the present invention.

[0056] Figure 16 It is a schematic diagram of the state of using a projection lamp to guide the adjustment of the lighting area of the lamp during the lamp holder debugging process in Embodiment 2 of the present invention.

[0057] Figure 17 It is a flowchart of the intelligent learning desk in Embodiment 2 executing the posture supervision and correction process.

[0058] The markings in the figure are:

[0059] 1. Table; 2. Chair; 3. Lamp; 4. Camera; 5. Alarm; 31. Lamp stand; 32. Lighting source; 33. Projection lamp; 311. Vertical stand; 312. Connecting stand; 313. Horizontal stand. Detailed implementation manner

[0060] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0061] Embodiment 1

[0062] This embodiment provides a writing posture supervision method for supervising the sitting posture, pen-holding posture and writing posture of a writing user. The writing posture supervision method provided in this embodiment generally includes the following processes: First, detect the relative position of the user's eyes and the desktop, and judge whether the user's sitting posture is normal. Secondly, under the condition that the user's sitting posture is normal, determine the optimal pen-down range of the pen tip on the desktop when the user holds the pen for writing according to the user's body size data, that is, the optimal writing area. And detect whether the actual pen tip position of the user is within the optimal writing area, and use this as a basis for judging whether the user's pen-holding posture is normal. Finally, detect whether the spatial projection of the pen shaft relative to the eyes when the user holds the pen is within a preset reasonable spatial range, and use this as a basis for judging whether the user's writing posture is normal.

[0063] Specifically, as Figure 1 shown, the writing posture supervision method provided in this embodiment includes the following steps:

[0064] S1: Take the long side and the short side of the horizontal rectangular desktop as the X and Y axes respectively, and the vertical direction as the Z axis to establish a spatial coordinate system.

[0065] S2: Obtain the lighting effects of the lighting lamps on various parts of the rectangular desktop, and define the area on the rectangular desktop that meets the daylighting and lighting hygiene standards as the writing plane. The position distribution of the writing plane is as Figure 2 shown.

[0066] The concept of the writing plane proposed in the solution of this embodiment refers to: under lighting conditions, the area on the desktop where the daylighting and lighting hygiene standards can meet the needs of normal writing. Generally speaking, for a specific model of lamp, after it is installed at a specified position above the desktop at a specific irradiation angle, the area within the lighting range of the lamp that meets the writing needs is actually fixed; therefore, technicians can determine the actual distribution range of the writing plane above the desktop through actual measurement and prompt the user of the distribution area of this "writing plane" through corresponding indication information. Of course, for a specific model of lamp, when parameters such as the relative position and irradiation angle between the light source and the desktop are adjusted, the distribution area of the "writing plane" will also be adjusted accordingly.

[0067] The solution provided in this embodiment refers to two national standards, namely "Hygienic Standards for Daylighting and Lighting in Primary and Middle School Classrooms (GB 7793-2010)" and "Performance Requirements for Reading and Writing Desk Lamps (GB / T 9473-2008)", and sets relevant indicators for the area above the desktop that meets the daylighting and lighting hygiene standards. Among them, the items of the test indicators include: average illuminance value, surface uniformity of illumination, color temperature and color rendering index, anti-glare performance, anti-blue light performance, and low-frequency flicker performance, etc.

[0068] In order to indicate the distribution area of the writing plane, a projection spotlight is provided on one side of the lamp corresponding to the lighting light source in this embodiment. The projection spotlight is used to project a pattern that coincides with the area that meets the daylighting and lighting hygiene standards generated by the lighting light source on the surface of the lower rectangular desktop to prompt the user of the position of the writing plane.

[0069] S3: Real-time collect the positions of the user's two eyes in the space coordinate system, and judge whether the user's sitting posture is correct according to the relative position between the two eyes and the rectangular desktop:

[0070] (1) When the relative position between the two eyes and the rectangular desktop meets the requirements, proceed to the next step.

[0071] (2) When the relative position between the two eyes and the rectangular desktop does not meet the requirements, send a warning message indicating abnormal sitting posture;

[0072] The indicators used in this embodiment to judge the correct sitting posture of the user include the following two items, and only when the user meets both of the following two indicators at the same time, it is determined that the user's sitting posture is normal:

[0073] A. The average height value of the user's two eyes from the plane of the rectangular desktop is within the preset height range.

[0074] B. The angle between the spatial connection line of the user's two eyes and the long side of the rectangular desktop is within the preset angle range.

[0075] Among them, for index A, a reasonable height range can be determined in different ways. For example: a determination method based on the individual differences of users (Method 1) and a determination method based on the physiological characteristics of users (Method 2), etc. In Method 1, technicians can pre-collect the vertical height of the eyes of a specified user from the desktop in the normal writing state, then record the corresponding height value as the standard value, and then during the user's writing process, continuously detect the binocular height value of the user and determine whether the deviation between the user's real-time binocular height and the standard value is within a preset fluctuation range (such as ±35%). If so, it is determined that the current index of the user is normal, otherwise it is determined that the current index of the user is abnormal. In Method 2, technicians first test the eye height fluctuation range of users with different heights or body types during normal writing and record a corresponding height interval, then obtain the height or body type data of the current user and match an allowed height fluctuation range for it. Next, continuously detect the binocular height value of the user and determine whether the user's real-time binocular height is within the allowed range. If so, it is determined that the current index is normal, otherwise it is determined that the current index is abnormal.

[0076] For index B, the preset included angle range between the user's binoculars and the long side of the desktop is 45°. When the actual fixture exceeds 45°, it is determined that the current index is abnormal.

[0077] S4: Obtain the body type data of the user, and determine the user's body position according to the positions of the user's binoculars; then specify an ergonomic optimal writing area in the writing plane by combining the body type data and the body position. The position of the optimal writing area is as Figure 3 shown.

[0078] In this embodiment, the reference point of the optimal writing area is the user's body position. The optimal writing area is actually a rectangular area with a specified area on the desktop in the specified direction of the body position. Specifically, as Figure 4 shown, the division method of the optimal writing area in this embodiment includes the following process:

[0079] I. Prior data generation

[0080] (a) Divide the user group into multiple different body types by combining two indicators of height and BMI index.

[0081] In this embodiment, the height index of the user is divided into: below 110 cm, 110 - 125 cm, 125 - 140 cm, 140 - 155 cm, 155 - 170 cm, 170 - 180 cm, and above 180 cm, a total of 7 intervals. The BMI value of the user is divided into 4 intervals: below 20, 20 - 25, 25 - 30, and above 30. Finally, 28 different user body types can be obtained by combining height and weight data.

[0082] In this embodiment, different height intervals are coded from low to high, recorded as 1-7, and different BMI indexes are coded from small to large, recorded as 1-4. At this time, the label HxBy is used to represent the user's body type category, where x represents the group corresponding to the user's height, and y represents the group corresponding to the user's BMI index.

[0083] For example, when a user's height is 175 cm, weight is 70 kg, and BMI is calculated to be 22.9, the user's height belongs to the 6th level, and the BMI index belongs to the 2nd level, so the corresponding user body type category is recorded as H6B2.

[0084] (b) Test the maximum movement range of the pen tip on the desktop when users of different body types are writing normally.

[0085] (c) Generate a circumscribed rectangle corresponding to the maximum motion range of the pen tip, so that each side of the circumscribed rectangle is parallel to each side of the rectangular desktop; and record the current body position of the user.

[0086] (d) The area of ​​the above-mentioned circumscribed rectangle on the side specified by the body position is used as the optimal writing area for the user of the current body shape.

[0087] (e) constructing an optimal writing area distribution database, in which a mapping relationship between each type of user's body shape and the respective optimal writing area distribution relationship is established.

[0088] 2. Current User Matching

[0089] (e) Get the current user’s height and weight and calculate the user’s BMI index.

[0090] (f) Determine the current user's body shape by combining height and BMI index.

[0091] (g) According to the current user's body shape, query the optimal writing area distribution database to determine the current user's optimal writing area.

[0092] S5: The position of the pen tip when the user is writing is collected in real time, and the following judgments and decisions are made based on the position of the pen tip:

[0093] (1) Figure 5 As shown, when the pen tip is located within the optimal writing area, the next step is entered;

[0094] (2) Figure 6 As shown, when the pen tip position is outside the optimal writing area, a warning message indicating an abnormal pen holding posture is issued;

[0095] S6: Combine the pen tip position and the user's posture information in the sitting state to generate a virtual writing frame in the optimal writing area.Figure 7 and Figure 8 As shown in Figure 8 , the method for generating the writing frame in this embodiment is as follows:

[0096] S61: Establish a plane coordinate system with the direction of the line connecting the two eyes as the horizontal axis and the direction of the perpendicular foot from the pen tip to the horizontal axis as the vertical axis.

[0097] S62: Draw a t-shaped grid with a preset size in the plane coordinate system with the pen tip position as the center P.

[0098] S63: Rotate the t-shaped grid around the center P until each side of the t-shaped grid is parallel to the horizontal axis or the vertical axis of the plane coordinate system; the t-shaped grid at this time is the required writing frame.

[0099] S7: Combine the reasonable offset range of the human body during the writing process, calculate the projection range limit of the pen shaft within the writing frame, and generate a corresponding reasonable writing projection area;

[0100] S8: Real-time collect the position of any sampling point on the pen shaft near the pen cap side when the user is writing, and establish a virtual pen shaft model in the space coordinate system;

[0101] S9: Take the eye position as the light source position and the rectangular desktop as the projection surface; calculate the projection position of the pen shaft model on the projection surface under the light source irradiation condition according to the spatial projection geometry, and make the following decisions based on the projection position:

[0102] (1) As Figure 9 shown, when the projection position is within the reasonable writing projection area, it is confirmed that the user's writing posture is normal;

[0103] (2) As Figure 10 shown, when the projection position exceeds the reasonable writing projection area, it is confirmed that the user's writing posture is abnormal and a warning is issued.

[0104] In the solution provided in this embodiment, the reasonable writing projection area reflects the spatial projection relationship between the eyes and the pen shaft corresponding to all users in the normal writing posture. This projection relationship has a relatively small correlation with the physiological differences between users, so it can be used to characterize the user's current pen-holding posture and writing posture. This embodiment uses the spatial projection relationship between the eyes and the pen shaft as the criterion for evaluating the user's writing posture.

[0105] When using the projection relationship between the eyes and the pen shaft as the criterion for evaluating the user's writing posture, it is also necessary to determine the typical distribution range of the spatial projection between the eyes and the pen shaft when the user is writing normally. This embodiment defines the concept of a reasonable writing projection area to refer to this interval, and uses a large number of representative sample data collected to finally determine the confidence interval of a reasonable writing projection area. Specifically, in step S7 of this embodiment, as Figure 11As shown in the figure, the method for determining the reasonable writing projection area is as follows:

[0106] S01: Select people of different ages, body types, and genders as testers.

[0107] S02: Obtain the relative positions of the eyes and the pen shaft of each tester during normal writing.

[0108] S03: Record multiple sets of sample data generated when the body and the pen tip positions of each tester are reasonably adjusted to form a sample data set.

[0109] S04: Determine the writing frame corresponding to each set of sample data in the sample data set, and calculate the projection generated by the pen shaft within the writing frame for each set of sample data.

[0110] S05: Define the distribution area of the projections corresponding to all sample data during the test process as the reasonable writing projection area.

[0111] In the actual application process of the solution of this embodiment, the judgment process of the writing posture in step S9 can be selected to be analyzed by means of vector operations. Combining Figure 12 , the specific operation process of this embodiment is as follows:

[0112] 1. Assume that the collected pen tip position is P, and any point on the pen shaft is Q', then the vector of the pen shaft is Furthermore, the vector corresponding to the projection of the pen shaft on the writing plane can be calculated as

[0113] 2. According to the pre-generated reasonable writing projection area, determine that its boundary vectors are respectively and

[0114] 3. Define the Z-axis direction vector as e z , and make the following judgments:

[0115] (1) If it satisfies: the vector mixed product and the vector mixed product Then it is determined that the pen shaft projection PQ is distributed in the reasonable writing projection area, and the user's current writing posture is normal.

[0116] (2) If it does not satisfy: the vector mixed product and the vector mixed product Then it is determined that the pen shaft projection PQ exceeds the reasonable writing projection area, and the user's current writing posture is abnormal.

[0117] In the actual application process, various different means can be used to determine the spatial positions of the user's eyes and the pen. In this embodiment, the position detection of the target object is mainly achieved by using an image recognition algorithm and an image-based spatial position detection algorithm. In steps S3, S5, and S8, sample images of the corresponding areas of the user's face and hand are respectively collected by a camera; then, the areas of the eyes, pen tip, and pen barrel included in the sample images are identified through the image recognition algorithm, and finally, an image-based target spatial position calculation method is used to determine the spatial positions of the corresponding targets in the sample images. Among them, in order to obtain higher-precision position information, in steps S3, S5, and S8, a multi-camera or depth camera is selected to obtain the sample images of the target. There are already mature related solutions for target recognition and positioning based on images in the prior art, and the technical content of this part will not be elaborated in this embodiment.

[0118] Embodiment 2

[0119] Based on the writing posture supervision method provided in Embodiment 1, this embodiment further provides an intelligent learning desk with a posture correction function. As Figure 13 shown, it includes: a desk and chair body, a lamp 3, at least two groups of cameras 4, an alarm 5, and a device manager.

[0120] Among them, the desk and chair body includes a table 1 with a horizontal desktop and a chair 2. The lamp 3 includes a lamp stand 31, a lighting light source 32, and a projection lamp 33. The projection lamp 33 is used to generate guiding information for the installation and adjustment of the lamp stand 31 on the desktop. The lamp stand 31 includes a plurality of movable joints and has functions of lifting, rotating, and pitching adjustment. The cameras 4 are respectively installed on the brackets of the lamp 3; the two groups of cameras 4 are respectively used to obtain the user's face image and the user's hand image. The alarm 5 is used to send a posture correction prompt message when receiving any abnormal information.

[0121] In the intelligent learning desk with a posture correction function provided in this embodiment, as Figure 14 shown, the lamp stand 31 includes a vertical stand 311, a horizontal stand 313, and a connecting stand 312. The bottom of the vertical stand 311 is fixedly connected to the table 1, and the top is movably connected to one end of the connecting stand 312 through a hinge one. One end of the horizontal stand 313 is movably connected to the other end of the connecting stand 312 through a hinge two. The hinge one and the hinge two enable the horizontal stand 313 to perform pitching adjustment relative to the vertical stand 311. The vertical stand 311 adopts a two-section structure, and at least one section adopts a telescopic stand. The two sections of the vertical stand 311 are connected by a joint one, and the two can rotate coaxially relative to each other. The horizontal stand 313 also adopts a two-section structure, and the two sections of the horizontal stand 313 are connected by a joint two, and the two can rotate coaxially relative to each other.

[0122] In this embodiment, the illumination light source 32, the projection lamp 33, and the camera 4 are respectively installed at different positions on the lamp holder 31. Specifically, the illumination light source 32 is installed at the bottom of the crossbar 313. The camera 4 includes a first camera 4 on the side of the lamp 3 close to the user and a second camera 4 on the side of the lamp holder 31 close to the desktop. The first camera 4 captures the user's face image, and the second camera 4 captures the user's hand image. In this embodiment, both the first camera 4 and the second camera 4 are selected to be depth cameras or multi-cameras. The projection lamp 33 is installed on the same side as the illumination light source 32 and is used to project patterns onto the desktop.

[0123] The device manager includes a control module and a data processing module. As Figure 15 shown, the control module is electrically connected to the projection lamp 33, the illumination light source 32, and the alarm 5; the data processing module is electrically connected to the camera 4. The data processing module includes an information collection unit, a storage unit, a first judgment unit, a second judgment unit, and a third judgment unit. The first judgment unit, the second judgment unit, and the third judgment unit are used to respectively judge whether the user's sitting posture, pen-holding posture, and writing posture are normal. When any of the three detects an abnormality, the abnormal result is sent to the control module.

[0124] The device manager in this embodiment also includes a communication unit, which is used to communicate and connect with other devices to perform data transmission between other devices and the device manager; other devices send physiological characteristic data input by the user to the device manager.

[0125] In the data processing module of the device manager, the information collection unit is used to obtain the user's physiological characteristic data. The information collection unit requires that the physiological characteristic data input by the user at least includes: age, gender, height, weight, and dominant hand. The information about the dominant hand is mainly used for the second judgment unit to determine the distribution direction of the optimal writing area relative to the human eye: when the current user is left-handed, the optimal writing area is located in the specified area on the left side relative to the human eye; when the current user is right-handed, the optimal writing area is located in the specified area on the right side relative to the human eye.

[0126] The storage unit stores an optimal writing area distribution mapping table and a parameter set of a reasonable writing projection area. The optimal writing area is used to represent the allowable range of the pen tip landing point when the current user writes on the desktop in a normal posture; among them, the user's body type is characterized by combining height and BMI index; for two users with the same body type but different dominant hands, the distribution positions of their corresponding optimal writing areas on the desktop are symmetric.

[0127] Among them, the distribution range of the optimal writing area corresponding to users with different body types is established in the optimal writing area distribution mapping table. The optimal writing area is rectangular. CombiningFigure 12 The data format for defining the optimal writing area distribution mapping table is: {type, α, L, H}; where type represents the body type category of the current user; α represents the horizontal angle between the optimal writing area and the position of the human eyes; L represents the length of the optimal writing area along the length direction of the desktop; H represents the length of the optimal writing area along the width direction of the desktop.

[0128] There is a trained face recognition model running in the first judgment unit. When the first judgment unit obtains the user's facial image collected by the camera 4, the face recognition model can identify and locate the two eyes from the collected user's facial image, and then calculate the true spatial positions of the two eyes by combining the camera parameters and the pixel positions of the human eyes in the user's facial image. Finally, it is judged whether the user's sitting posture is abnormal according to whether the relative position between the user's two eyes and the desktop meets the specification. If the relative position between the human eyes and the desktop meets the specification, it means that the user's sitting posture is normal, otherwise it is determined that the user's sitting posture is abnormal.

[0129] In this embodiment, the criteria for the first judgment unit to judge that the user's sitting posture is normal are that the following two conditions are met simultaneously:

[0130] (1) The average height value of the user's two eyes from the plane of the rectangular desktop is within a preset height range;

[0131] (2) The angle between the spatial connection line of the user's two eyes and the long side of the rectangular desktop is within a preset angle range.

[0132] In a more optimized solution of other embodiments, pressure sensors are also provided at the positions of the chair 2, the seat cushion and the backrest; the pressure sensors are communicatively connected to the data processing module. The detection results of the pressure sensors are introduced into the determination of the user's sitting posture. At this time, the criteria for the first judgment unit to judge that the user's sitting posture is normal are that the following four conditions are met simultaneously:

[0133] (1) The average height value of the user's two eyes from the plane of the rectangular desktop is within a preset height range;

[0134] (2) The angle between the spatial connection line of the user's two eyes and the long side of the rectangular desktop is within a preset angle range;

[0135] (3) The fluctuation of the pressure signal at the seat cushion is within a preset amplitude;

[0136] (4) The fluctuation of the pressure signal at the backrest is within a preset amplitude.

[0137] There is an image recognition model for a human hand or pen running in the second judgment unit. The image recognition model can identify and calculate the landing position of the pen tip held by the user on the desktop based on the user hand image collected by the camera 4. Then, it queries the optimal writing area distribution mapping table to obtain the optimal writing area of the current user. Finally, it determines whether the user's pen-holding posture is abnormal based on whether the actual landing position is within the optimal writing area. When the pen tip held by the user lands within the optimal writing area, it is determined that the current pen-holding posture of the user is normal; otherwise, it is determined that the current pen-holding posture of the user is abnormal.

[0138] The third judgment unit is used to obtain the user hand image collected by the camera 4, identify and calculate the spatial position of the pen shaft held by the user. Then, it calculates the projection position of the pen shaft on the desktop when the human eye is used as the light source. Finally, it determines whether the projection position of the pen shaft is within the reasonable writing projection area, and further determines whether the user's writing posture is abnormal.

[0139] The judgment process of the third judgment unit is as follows:

[0140] (1) Calculate the central position E0 of the human eye, the pen tip position P, and any point position Q' on the pen shaft.

[0141] (2) Determine the vector of the pen shaft as Furthermore, calculate the vector corresponding to the projection of the pen shaft in the desktop when the central position E0 of the human eye is used as the light source

[0142] (3) Query the parameter set of the reasonable writing projection area, and determine that the boundary vectors of the reasonable writing projection area are respectively and

[0143] (4) Define the Z-axis direction vector in the space above the desktop as e z , calculate the vector mixed product and the vector mixed product values, and make the following judgments and decisions:

[0144] When both are greater than 0, it is determined that the pen shaft projection PQ is distributed in the reasonable writing projection area, and the current writing posture of the user is normal; otherwise, it is determined that the pen shaft projection PQ exceeds the reasonable writing projection area, and the current writing posture of the user is abnormal.

[0145] To make the advantages of the intelligent learning desk with posture correction function provided by this embodiment more obvious, the following further describes it in combination with the installation test and use process of this intelligent school desk:

[0146] The desk and chair body in the intelligent learning desk provided in this embodiment is the same as that of a conventional desk and chair product, and the product assembly can be completed by using an assembly method similar to that of a conventional desk and chair. In particular, for some upgraded products with pressure sensors installed at the seat cushion and backrest, the pressure sensors of the chair 2 need to be paired and connected with the device manager built into the desk 1 through a wireless communication module. After the pairing is completed, the pressure sensors will send detection data to the device manager at a preset sampling frequency. To ensure the flexibility of the product, the device manager, lamp 3, alarm 5, and camera 4 in the desk 1 of this embodiment are connected to the 220V mains power supply. The pressure sensors and wireless communication modules in the chair 2 are powered by removable batteries.

[0147] Combined with Figure 13 it can be known that: The lamp 3 in this embodiment is installed on one side of the desk 1, and the irradiation angle of the illumination light source 32 is adjusted through the lamp holder 31. Considering that the illumination effect of the light source will affect the user's experience and even the user's physical health. In this embodiment, the bracket is designed as a multi-joint adjustable type as Figure 14 . Among them, the vertical frame 311 of the telescopic frame can be used to adjust the height of the light source from the lower desktop. The two ends of the vertical frame 311 are rotatable designs, allowing the user to rotate the horizontal frame 313 into or out of the desktop. The two ends of the connecting frame 312 are respectively connected to the vertical frame 311 and the horizontal frame 313 by hinges, so that the three parts of the lamp holder 31 can perform bending actions similar to those of an arm, thereby realizing the pitching adjustment of the illumination light source 32. The user can change the coverage range of the light source and the illumination intensity above the desktop through the above various adjustment methods to meet their own lighting needs during the writing process. In this embodiment, the horizontal frame 313 in the lamp holder 31 also adopts a two-section rotatable structure, which enables the user to flexibly adjust the irradiation angle or viewing direction of the illumination light source 32, projection lamp 33, and camera 4 installed thereon.

[0148] Among them, after the lamp 3 is assembled, the lighting area also needs to be debugged. In this embodiment, the projection lamp 33 under the horizontal frame 313 is used to assist in adjusting the lighting area of the lamp 3, as Figure 16 shown. The specific operation process is as follows:

[0149] 1. Turn on the projection lamp 33. When the projection lamp 33 is turned on, a pattern for characterizing the area range that meets the lighting requirements is generated below.

[0150] 2. Adjust the connection states of the horizontal frame 313, vertical frame 311, and connecting frame 312 in the lamp holder 31 so that the pattern generated by the projection lamp 33 coincides with the specified area on the lower desktop. Among them, guiding lines are added to the specified area on the desktop.

[0151] 3. After the above adjustments are completed, fix the states of Hinge 1, Hinge 2, Joint 1, and Joint 2 in the lamp holder 31. At this time, the specified areas on the lower desktop all meet the lighting requirements after the lighting source 32 is turned on.

[0152] After the intelligent study desk is installed, the user should interact with the device manager to bind the user and input user information to the device manager. This part of the content can refer to the interaction logic of currently very mature intelligent household appliances. For example, the user binds the intelligent study desk to an electronic device (such as: mobile phone, bracelet, watch, tablet computer, etc.) running a specific application (APP) in the user's hand by scanning the code. Then upload user data to the device manager in the application. The uploaded user data includes at least: age, gender, height, weight, dominant hand, and so on. In addition, for products with pressure sensors installed in the chair 2, the user should also try out the product in advance, and the device manager records the initial pressure signals detected by each pressure sensor when the user is sitting on the chair 2 under normal use conditions. In addition, considering that the physiological characteristic data of the user is a key parameter for the normal operation of the intelligent study desk and will also affect the correction effect of the intelligent study desk; therefore, these data should be updated regularly. In this embodiment, for underage users, the initial pressure signal and other physiological characteristic data are re-collected and updated monthly, while for corresponding adults, the data update cycle can be appropriately extended.

[0153] After completing the above initialization settings, the user can use this type of intelligent study desk with posture correction function to supervise and correct their own writing postures. The usage process of the intelligent study desk is as Figure 17 shown, including the following processes:

[0154] In the initial state, the lighting source 32 is turned off, and the device manager remains in the standby state. When the lighting source 32 is powered on, the intelligent device manager runs, and the first camera 4 captures the face image of the user at the position of the opposite chair 2. When the face image capture fails repeatedly for multiple times, it is determined that the light source is turned on by mistake, and the device manager turns off the lighting source 32 and returns to the standby state.

[0155] When the face image is captured successfully, the device manager enters the supervision stage, and the device manager repeatedly executes the following tasks in the supervision stage:

[0156] The first judgment unit first analyzes whether the user's current sitting posture is normal. If so, it proceeds to the next step; otherwise, it drives the alarm 5 to give a reminder that the user's sitting posture is abnormal until the user adjusts the sitting posture to normal. Next, the second judgment unit obtains the user's hand image collected by the second camera 4, identifies and calculates the position of the tip of the pen held by the user, and then determines whether the tip position is within the specified optimal writing area. If so, it proceeds to the next step; otherwise, it drives the alarm 5 to give a reminder that the user's pen-holding posture is abnormal until the user adjusts the pen-holding posture to normal. Finally, the third judgment unit identifies the spatial positions of any two points on the pen held by the user and calculates the spatial position of the pen shaft held by the user. Then it calculates the projection position of the pen shaft on the desktop when the human eye is used as the light source; finally, it determines whether the projection position of the pen shaft is within the reasonable writing projection area. If so, it determines that the user's writing posture is normal; otherwise, it drives the alarm 5 to give a reminder that the user's writing posture is abnormal until the user adjusts the writing posture to normal.

[0157] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An intelligent learning desk with a posture correction function; It is characterized in that, It includes: A desk and chair body, which includes a table with a horizontal desktop and a chair; A lamp, which includes a lamp stand, a lighting source and a projection lamp, and the projection lamp is used to generate guiding information for adjusting the lamp stand on the desktop; the lamp stand includes a plurality of movable joints and has functions of lifting, rotating and pitching adjustment; At least two groups of cameras, which are respectively installed on the brackets of the lamp; the two groups of cameras are respectively used to acquire user's facial images and user's hand images; An alarm, which is used to send a posture correction prompt message when receiving any abnormal information; A device manager, which includes a control module and a data processing module; the control module is electrically connected to the projection lamp, the lighting source and the alarm; the data processing module is electrically connected to the camera, and the data processing module includes an information acquisition unit, a storage unit, a first judgment unit, a second judgment unit, and a third judgment unit; the information acquisition unit is used to acquire the physiological characteristic data of the user; The storage unit stores a best writing area distribution mapping table and a parameter set of a reasonable writing projection area; the first judgment unit is used to acquire the user's facial image collected by the camera, identify and calculate the spatial positions of both eyes; then judge whether the user's sitting posture is abnormal according to whether the relative positions of the user's both eyes and the desktop meet the specifications; the second judgment unit is used to acquire the user's hand image collected by the camera, identify and calculate the landing position of the pen tip held by the user on the desktop; then query the best writing area distribution mapping table to obtain the best writing area of the current user; finally judge whether the user's pen-holding posture is abnormal according to whether the actual landing position is located in the best writing area; the third judgment unit is used to acquire the user's hand image collected by the camera, identify and calculate the spatial position of the pen shaft held by the user; then calculate the projection position of the pen shaft on the desktop when the human eye is used as the light source; finally judge whether the projection position of the pen shaft is located in the reasonable writing projection area, and then judge whether the user's writing posture is abnormal; the abnormal results generated by the first judgment unit, the second judgment unit and the third judgment unit are sent to the control module.

2. The intelligent learning desk with a posture correction function according to claim 1, It is characterized in that: The information acquisition unit requires that the physiological characteristic data input by the user at least includes: age, gender, height, weight, and dominant hand; Among them, the second judgment unit judges the distribution direction of the best writing area relative to the human eye according to the information of the dominant hand obtained: when the current user is left-handed, the best writing area is located in the designated area on the left side relative to the human eye; when the current user is right-handed, the best writing area is located in the designated area on the right side relative to the human eye.

3. The intelligent learning desk with a posture correction function according to claim 2, It is characterized in that: The optimal writing area is used to characterize the allowable range of the pen tip landing point when the current user writes on the desktop in a normal posture; among them, the user's body type is characterized by combining height and BMI index; for two users with the same body type but different dominant hands, the distribution positions of their corresponding optimal writing areas on the desktop are symmetrical; In the optimal writing area distribution mapping table, the distribution ranges of the optimal writing areas corresponding to users with different body types are established, and the optimal writing area is rectangular; the data format of the optimal writing area distribution mapping table is defined as: {type, α, L, H}; where type represents the body type category of the current user; α represents the horizontal angle of the optimal writing area relative to the position of the human eye; L represents the length of the optimal writing area along the length direction of the desktop; H represents the length of the optimal writing area along the width direction of the desktop.

4. The intelligent study desk with a posture correction function according to claim 1, characterized in that: The judgment process of the third judgment unit is as follows: (1) Calculate the central position E0 of the human eye, the pen tip position P, and any point position Q' on the pen barrel; (2) Determine the vector of the pen barrel as Furthermore, when the center position E0 of the human eye is used as the light source, calculate the vector corresponding to the projection of the pen barrel on the desktop (3) Query the parameter set of the reasonable writing projection area, and determine that the boundary vectors of the reasonable writing projection area are respectively and (4) Define the Z-axis direction vector of the space above the desktop as e z , calculate the vector triple product and the vector triple product values, and make the following judgments and decisions: When both are greater than 0, it is determined that the pen barrel projection PQ is distributed in the reasonable writing projection area, and the user's current writing posture is normal; otherwise, it is determined that the pen barrel projection PQ exceeds the reasonable writing projection area, and the user's current writing posture is abnormal.

5. The intelligent study desk with a posture correction function according to claim 1, characterized in that: The criterion for the first judgment unit to judge that the user's sitting posture is normal is that the following two conditions are met simultaneously: (1) The average height value of the user's eyes from the plane of the rectangular desktop is within a preset height range; (2) The angle between the spatial connection line of the user's eyes and the long side of the rectangular desktop is within a preset angle range.

6. The intelligent study desk with a posture correction function according to claim 5, characterized in that: Pressure sensors are provided at the positions of the chair, seat cushion and backrest; the pressure sensors are communicatively connected to the data processing module and send detection signals to the data processing module; the criterion for the first judgment unit to judge that the user's sitting posture is normal is that the following four conditions are met simultaneously: (1) The average height value of the user's eyes from the plane of the rectangular desktop is within a preset height range; (2) The angle between the spatial connection line of the user's eyes and the long side of the rectangular desktop is within a preset angle range; (3) The fluctuation of the pressure signal at the seat cushion is within a preset amplitude; (4) The fluctuation of the pressure signal at the backrest is within a preset amplitude.

7. The intelligent study desk with a posture correction function according to claim 1, characterized in that: The lamp holder includes a vertical frame, a horizontal frame and a connecting frame. The bottom of the vertical frame is fixedly connected to the table, and the top is movably connected to one end of the connecting frame through a first hinge; one end of the horizontal frame is movably connected to the other end of the connecting frame through a second hinge; the first hinge and the second hinge enable the horizontal frame to be adjusted in pitch relative to the vertical frame; the vertical frame adopts a two-section structure, and at least one section adopts a telescopic frame; the two sections of the vertical frame are connected by a first joint and can rotate coaxially relative to each other; the horizontal frame also adopts a two-section structure, and the two sections of the horizontal frame are connected by a second joint and can rotate coaxially relative to each other.

8. The intelligent study desk with posture correction function as claimed in claim 7, characterized in that: The process of installing and debugging the lamp using the projection lamp is as follows: First, when the projection lamp is turned on, a pattern for representing the area range meeting the lighting requirements is generated below; Second, adjust the connection states of the horizontal frame, vertical frame and connecting frame in the lamp holder so that the pattern generated by the projection lamp coincides with the specified area on the table below; Third, after the above adjustment, fix the states of the first hinge, second hinge, first joint and second joint in the lamp holder. At this time, the specified area on the table below meets the lighting requirements after the lighting source is turned on.

9. The intelligent study desk with posture correction function as claimed in claim 1, characterized in that: The camera adopts a depth camera or a multi-camera; and / or When the first judgment unit and the second judgment unit in the data processing module fail to detect the face and hand images within a preset period; the control module automatically turns off the lighting source.

10. The intelligent study desk with posture correction function as claimed in claim 1, characterized in that: The device manager further includes a communication unit, which is used for communication connection with other devices to perform data transmission between other devices and the device manager; the other devices send the physiological characteristic data input by the user to the device manager.

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