Wearable walking posture judgment wireless sensing system

Abstract

The invention relates to a wearable walking posture judgment wireless sensing system, and belongs to the technical field of sensors, plantar pressure analysis and embedded analysis. The wearable walking posture judgment wireless sensing system comprises a rear foot bottom plate, a first three-dimensional force sensor, a rear foot panel, a front foot bottom plate, a pin shaft, two second three-dimensional force sensors and a front foot panel. According to the wearable walking posture judgment wireless sensing system and the identification algorithm of the balance in different walking posture states, the specific phase in the human body gait is judged and the balance of the walking posture of the human body gait is monitored by detecting the mechanical signal and the inertial signal, so that protection measures can be effectively taken when the human body is about to be unstable; the three-dimensional force of the sole of the human body is detected, the specific gait phase of the human body is judged, and a detection and analysis tool can be provided for an exercise rehabilitation type robot.

Description

Technical Field

[0001] The invention relates to the technical fields of sensors, plantar pressure analysis and embedded analysis, and in particular to a wearable walking posture judgment wireless sensor system. Background Art

[0002] The detection and research of plantar pressure distribution has broad and profound significance. By measuring and analyzing the plantar pressure distribution of gait, scientific and reliable information can be provided for the study of foot structure, function and movement control. In rehabilitation medicine, plantar pressure analysis can provide an important basis for the diagnosis and rehabilitation treatment of some diseases, and identify patients according to their real-time status to prevent them from falling. It is also one of the important bases for effectively evaluating the mechanical structure of lower limb rehabilitation training and the feasibility of lower limb rehabilitation training programs. At present, the research on plantar pressure analysis will also have a positive promoting effect on many fields, such as biomedicine, sports training, ergonomics, shoemaking, robot control engineering and digital human body.

[0003] The research on plantar pressure measurement and analysis began in the 1960s and 1970s. The earliest use of copying technology was only to qualitatively explain the distribution of plantar pressure. With the development of sensor technology, the main methods for modern plantar pressure measurement include: force plate technology, force insole technology, plantar pressure platform imaging technology, etc., which are all test technologies developed on the basis of sensors. The main sensing technologies used are vibration, magnetic sensitivity, strain, stress, vacuum, etc. The commonly used force plate uses a flat plate as a support surface, and the tension and compression sensors are installed under the support surface according to a certain rule. The force plate can only measure the one-dimensional force transmitted to the sensor by the sole, while ignoring the three-dimensional force of the sensor's action point. In addition, the system is large, the equipment occupies a large space, and the price is expensive. The general force insole is to attach a piezoelectric sensor to the specified position of the special insole to measure the distribution of plantar force during gait, but this technology also has the same disadvantages as the force plate, which cannot measure three-dimensional force and is expensive. At present, the recognition algorithm is mostly used for tasks such as classification, regression and clustering. The main identification algorithms include least squares method, support vector machine, deep learning and neural network. These algorithms can only process data through software, but cannot collect data in real time for direct identification. They also occupy a lot of resources and are time-consuming, and need to be improved urgently. Summary of the invention

[0004] The present invention aims to solve the technical problems in the prior art and provides a wearable walking posture judgment wireless sensor system.

[0005] In order to solve the above technical problems, the technical solutions of the present invention are as follows:

[0006] A wearable walking posture judgment wireless sensing system comprises: a rear foot sole, a first three-dimensional force sensor, a rear foot panel, a front foot sole, a pin shaft, two second three-dimensional force sensors and a front foot panel;

[0007] The pin passes through the through hole at the corresponding position of the front end of the rear foot panel, then passes through the through hole at the corresponding position of the rear end of the front foot panel, and then passes through the through hole at the corresponding position of the front end of the rear foot panel to fit the gap, so that the rear foot panel and the front foot panel can rotate relative to each other;

[0008] An interference fit is adopted between the lower part of the first three-dimensional force sensor and the inner diameter of the circular stepped groove at the heel position on the rear foot sole to fix the position of the first three-dimensional force sensor;

[0009] The lower parts of the two second three-dimensional force sensors are respectively fitted with the inner diameters of the circular stepped grooves at the positions of the first metatarsal bone, the second metatarsal bone and the third metatarsal bone on the upper surface of the forefoot sole plate by interference fit to fix the positions of the two second three-dimensional force sensors;

[0010] The rear foot sole plate and the front foot sole plate are respectively provided with two grooves at the bottom, the rear foot panel and the front foot panel are provided with through holes at corresponding positions in the middle, and the rear foot panel and the front foot panel are fixedly connected by ropes;

[0011] A certain gap is maintained between the upper part of the first three-dimensional force sensor and the corresponding boss at the lower part of the rear foot panel, and a certain gap is maintained between the upper parts of the two second three-dimensional force sensors and the corresponding bosses at the lower part of the front foot panel, to ensure that the plantar force of the human body can be fully loaded onto the three three-dimensional force sensors to achieve accurate measurement.

[0012] In the above technical solution, the first three-dimensional force sensor includes: a top cover, a first pressure sensor, a first force guide platform, four second force guide platforms, a second pressure sensor, a ball and a first base;

[0013] A first pressure sensor is attached to the upper surface of the first force guiding platform, a groove is opened at the center of the lower surface of the top cover and is coaxially fixed to the first pressure sensor, and is gap-matched with the first force guiding platform; the lower surface of the first force guiding platform is an inverted pyramid, and each side surface is respectively fitted with a second force guiding platform; a second pressure sensor is attached to the opposite side of the four second force guiding platforms respectively fitted with the first force guiding platform; two open grooves are respectively provided at the bottom of the four second force guiding platforms, and a ball is respectively provided in each open groove, which is embedded downward in the groove at the corresponding position of the first base, so that the second pressure sensing surface is tightly pressed and contacted with the inner wall of the groove inside the first base, and the second force guiding platform moves along the groove direction through the rolling of the ball.

[0014] In the above technical solution, the second three-dimensional force sensor includes: a force-bearing platform, a first force guide ring, a first force measuring piece, a support, a second force guide ring, a second force measuring piece, a main control and a second base;

[0015] Blind holes are respectively arranged on the four walls of the bearing platform, and the supporting platform in the supporting member is embedded in the blind hole of the bearing platform for interference fit; the first telescopic rod in the first force measuring member is embedded in the blind hole at the corresponding position on the front side of the bearing platform and is fixedly connected;

[0016] The inner wall of the first force guide ring is provided with a boss and a slide rail which are pressed and contacted with the force bearing platform through two support members and two first force measuring members; the four walls of the first force guide ring are respectively provided with blind holes, and the support platform in the support member is inserted into the blind hole at the corresponding position of the first force guide ring with interference fit;

[0017] The inner wall of the second force guide ring is provided with a boss and a slide rail which are pressed and contacted by two first force measuring pieces and two support pieces. The second force measuring piece is coaxially fixedly connected to the center of the bottom of the force bearing platform through a second telescopic rod. The second force measuring piece is pressed and contacted with the inner upper surface of the second base through a third rigid ball, so that the second force measuring piece can slide freely in the inner groove of the second base, and the main control is fixedly connected to the corresponding position of the inner groove of the second base;

[0018] The first force measuring member includes: a first rigid ball, a slide rail, a first electrode plate, a first telescopic rod, a second electrode plate and a first spring; the first spring is coaxially nested in the first telescopic rod and fixedly connected to the corresponding position of the slide rail, and the other end of the first spring is fixedly connected to the corresponding position of the force bearing platform; the slide rail has a groove, and a first rigid ball is arranged in the groove, which is pressed and contacted with the groove at the corresponding position on the inner side of the first force guide ring; the first electrode plate is coaxially embedded in the groove at the corresponding position of the slide rail and fixedly connected, and the second electrode plate is coaxially embedded in the groove at the corresponding position of the side of the force bearing platform and fixedly connected; the first telescopic rod is embedded in the blind hole at the corresponding position of the first force guide ring and fixedly connected;

[0019] The support member includes: a second rigid ball and a support platform; four opening slots are distributed in a square shape at four points on the left side surface of the support platform, and four second rigid balls are respectively arranged in each opening slot, which are pressed and contacted with the boss at the corresponding position of the first force guide ring, and the support platform is coaxially fixedly connected with the blind hole at the corresponding position of the bearing platform, thereby fixing the limitation of the bearing platform in the left and right directions;

[0020] The second force measuring piece includes: a second telescopic rod, an electrode rod, a third electrode plate, a fourth electrode plate, a sleeve, a second spring, a fifth electrode plate, a bottom plate and a third rigid ball; the second telescopic rod is coaxially interference fit with the blind hole at the center of the bottom of the bearing platform, passes through the second spring and is coaxially fixedly connected to the corresponding position of the center of the bottom plate, and there are 4 opening grooves distributed in a square at the corresponding positions on the lower surface of the bottom plate, and a third rigid ball is arranged in each opening groove, which is pressed and contacted with the second base, the upper end of the electrode rod is coaxially matched with the blind hole at the corresponding position of the lower end of the bearing platform, and the lower end passes through the third electrode plate and is fixedly connected to the fourth electrode plate. The fourth electrode plate is located at the center of the sleeve, the third electrode plate is fixedly connected to the top of the sleeve, the fifth electrode plate is nested upwardly in the bottom end of the sleeve and is fixedly connected, and is embedded downwardly in the opening groove at the corresponding position of the bottom plate.

[0021] An algorithm for identifying the balance of a wearable walking posture judgment wireless sensor system in different walking posture states includes the following steps:

[0022] Step 1: Collect the foot force of the user during walking;

[0023] Step 2: Collect inertial signals from the soles of the user's feet when the user is walking normally, and compare them in real time with the database of angle changes between the soles of the feet and the ground during the walking process of healthy people to determine the gait cycle of the user's body;

[0024] The plantar pressure signal of the user's body during normal walking is collected, and the ground reaction force value change law database during the walking process of healthy people is compared in real time to determine the balance of the user's gait phase.

[0025] In the above technical solution, step 1 specifically includes the following steps:

[0026] Step 1.1: Establish a three-dimensional coordinate system with the center of the left and right ankles of the user standing in the coronal plane as the origin and the front of the user as the positive direction of the X-axis;

[0027] Step 1.2: Calculation of plantar force Based on 8 groups of subjects with different standard heights, the data was further standardized and the original data was subjected to multiple regression to obtain the following calculation formula:

[0028]

[0029] Where: F X 、F Y 、F Z It is the pressure of the sole of the foot on the ground in three axes during normal walking.

[0030] In the above technical solution, step 2 also includes: selecting a range of pressure sensitivity for the first three-dimensional force sensor according to the formula in step 1.2, taking the vertical pressure of a healthy human body on the ground during normal walking as a reference, and taking the plantar pressure in the front and back and left and right directions as a supplement, so as to select a suitable pressure sensitivity range, and the calculation formula is as follows:

[0031]

[0032] Where: It is divided into the range of pressure sensitivity required in the X, Y and Z axis directions, and θ is the angle between the plane where the side of the first force guide table is located and the horizontal plane;

[0033] In the above technical solution, step 2 also includes: selecting the stiffness of the spring used by the second three-dimensional force sensor according to the formula in step 1.2 and according to Hooke's law, and the calculation formula is as follows:

[0034] Fi =K i d i (i=X,Y,Z)

[0035] Where: F i is the magnitude of the three axial forces, K i Use the spring stiffness constants for the three axial forces, d i Elastic deformation of the spring used in the three axial directions.

[0036] In the above technical solution, step 2 specifically includes the following steps:

[0037] Step 2.1: Use the wearable walking posture judgment wireless sensor system to measure the three-dimensional force and inertial parameters of the plantar during walking;

[0038] Step 2.2: The specific calculation formula of the first three-dimensional plantar force is as follows:

[0039]

[0040] Where: F X 、F Y 、F Z They are the pressure of the sole of the foot on the ground in three axes during normal walking;

[0041] F 1 F is the indication of the second pressure sensor in the forward direction; 2 F is the indication of the second pressure sense in the rear direction; 3 F is the indication of the second pressure sensor in the right direction; 4 F is the indication of the second pressure sensor in the left direction; 5 is the indication of the first pressure sense;

[0042] Step 2.3: The specific calculation formula of the second three-dimensional plantar force is as follows:

[0043]

[0044] Where: F X 、F Y 、F Z They are the pressure of the sole of the foot on the ground in three axes during normal walking; K i The spring stiffness coefficient used for the axial force i; K z Use the spring stiffness coefficient for the z-axis force; A i A is the cross-sectional area of ​​the electrode plate used for the axial force; z is the cross-sectional area of ​​the electrode plate used for the z-axis force; C is the capacitance; ε is the dielectric constant of air;

[0045] Step 2.4: Determine the specific phase of the user's gait cycle and the balance in this phase based on the change pattern of the ground support reaction force and the angle between the sole of the foot and the ground during walking of a healthy person who is comparable to the user.

[0046] In the above technical solution, the inertial sensor used in the wearable walking posture judgment wireless sensor system collects the inertial parameter value of the angle of the sole of the foot to the ground during human walking at 200 Hz / s.

[0047] The present invention has the following beneficial effects:

[0048] The wearable walking posture judgment wireless sensor system of the present invention and the identification algorithm of balance in different walking posture states can judge the specific phase in human gait and monitor the balance of human gait and walking posture through the detection of mechanical signals and inertial signals, so as to effectively take protective measures when the human body is about to become unstable; detect the three-dimensional force of the human plantar and judge the specific phase of human gait, which can provide a detection and analysis tool for sports rehabilitation robots.

[0049] The wearable walking posture judgment wireless sensor system of the present invention is designed to be suitable for use in a home environment and can be used for multiple functions. It fills the technical gap in this field under the social background of an aging population and can reduce the occurrence of a series of diseases caused by falls in the elderly.

[0050] The wearable walking posture judgment wireless sensor system of the present invention has low cost and light weight, fills the technical gap in the field of healthy human walking kinematics detection and evaluation products, reduces the expenses caused by the occurrence of diseases, and has broad market application prospects.

[0051] The wearable walking posture judgment wireless sensor system of the present invention can effectively and accurately measure the three-axis forces of plantar pressure, and identify the walking posture balance through the core of the single-chip microcomputer itself, so as to obtain the best result with the most saved resources. In addition, the Internet of Things is used to realize the switching of the sensor, and Bluetooth is used for wireless transmission of data. The structure is simple, compact and low-cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0053] Figure 1 The figure is a hardware wiring diagram of the wearable walking posture determination wireless sensor system of the present invention.

[0054] Figure 2 This is a schematic diagram of the structure explosion of the plantar pressure measuring device of the wearable walking posture judgment wireless sensor system of the present invention.

[0055] Figure 3It is a schematic diagram of the explosion of the first three-dimensional force sensor structure of the wearable walking posture judgment wireless sensing system of the present invention.

[0056] Figure 4 It is a schematic diagram of the explosion of the second three-dimensional force sensor structure of the wearable walking posture judgment wireless sensing system of the present invention.

[0057] Figure 5 The figure is a cross-sectional schematic diagram of a second three-dimensional force sensor of the wearable walking posture determination wireless sensing system of the present invention.

[0058] Figure 6 This is a schematic diagram of the explosion structure of the first force measuring piece of the wearable walking posture judgment wireless sensor system of the present invention.

[0059] Figure 7 The figure is an exploded schematic diagram of the supporting structure of the wearable walking posture judgment wireless sensor system of the present invention.

[0060] Figure 8 This is a schematic diagram of the explosion of the second force measuring member structure of the wearable walking posture judgment wireless sensor system of the present invention.

[0061] Fig. 9 The present invention is a schematic diagram of a pressure collection circuit of a wearable walking posture judgment wireless sensor system.

[0062] Fig.10 This is a schematic diagram of a plantar pressure measuring device system of the wearable walking posture judgment wireless sensor system of the present invention.

[0063] Fig.11 The present invention is a schematic diagram of a walking posture judgment balance process of the wearable walking posture judgment wireless sensor system.

[0064] The reference numerals in the figures indicate:

[0065] 1- rear foot sole; 2- first three-dimensional force sensor; 3- rear foot panel; 4- front foot sole; 5- pin shaft; 6- second three-dimensional force sensor; 7- front foot panel;

[0066] 201-top cover; 202-first pressure sensor; 203-first force guide platform; 204-second force guide platform; 205-second pressure sensor; 206-ball; 207-first base;

[0067] 601-force bearing platform; 602-first force guide ring; 603-first force measuring piece; 604-supporting piece; 605-second force guide ring; 606-second force measuring piece; 607-main control; 608-second base;

[0068] 6031-first rigid ball; 6032-slide rail; 6033-first electrode plate; 6034-first telescopic rod; 6035-second electrode plate; 6036-first spring;

[0069] 6041-second rigid ball; 6042-supporting platform;

[0070] 6061 - second telescopic rod; 6062 - electrode rod; 6063 - third electrode plate; 6064 - fourth electrode plate; 6065 - sleeve; 6066 - second spring; 6067 - fifth electrode plate; 6068 - bottom plate; 6069 - third rigid ball. DETAILED DESCRIPTION

[0071] The inventive concept of the present invention is:

[0072] The wearable walking posture judgment wireless sensor system of the present invention is a system for studying the measurement and analysis of the three-dimensional force of the sole of the foot. The system can collect the sole force of the human body during walking, and judge whether the state of the person is stable through the sole force.

[0073] The three-dimensional force sensor module and inertial sensor provided by the wearable walking posture judgment wireless sensor system of the present invention, combined with the identification algorithm of the present invention in different walking posture states, can detect the mechanical state of the human plantar in real time, and be used for comparative analysis with the plantar mechanical laws and the plantar posture angle change laws of the normal human body process, to determine whether the specific phase of the human body's gait cycle is stable, which can provide necessary reference for the development of external auxiliary force rehabilitation equipment.

[0074] The present invention is described in detail below with reference to the accompanying drawings.

[0075] like Figure 1-11 As shown, the wearable walking posture judgment wireless sensing system of the present invention comprises seven parts: a rear foot sole 1, a first three-dimensional force sensor 2, a rear foot panel 3, a front foot sole 4, a pin 5, a second three-dimensional force sensor 6 and a front foot panel 7. Among them:

[0076] The pin shaft 5 passes through the through hole at the corresponding position of the front end of the rear foot panel 3 to the left, then passes through the through hole at the corresponding position of the rear end of the front foot panel 7 to the left, and then passes through the through hole at the corresponding position of the front end of the rear foot panel 3 to the left to fit with the gap, ensuring that the rear foot panel 3 and the front foot panel 7 can rotate, so that the user can achieve relative rotation of the forefoot and the rear foot during walking; an interference fit is adopted between the lower part of the first three-dimensional force sensor 2 and the inner diameter of the circular step groove at the heel position on the upper surface of the rear foot sole 1 to fix the position of the first three-dimensional force sensor 2; an interference fit is adopted between the lower part of the second three-dimensional force sensor 5 and the inner diameter of the circular step groove at the first metatarsal and the second and third metatarsal positions on the upper surface of the front foot sole 4 , to fix the second three-dimensional force sensor 6; the rear foot sole 1 and the front foot sole 4 are respectively provided with two grooves at the bottom, and the rear foot panel 3 and the front foot panel 7 are provided with through holes at the corresponding middle positions, and the two are fixedly connected by ropes to connect the soles and the foot panels together to ensure that the rear foot sole 1 and the rear foot panel 3 as well as the front foot sole 4 and the front foot panel 7 are always in close contact; a certain gap is maintained between the upper part of the first three-dimensional force sensor 2 and the corresponding boss at the lower part of the rear foot panel 3, and a certain gap is maintained between the upper part of the two second three-dimensional force sensors 6 and the corresponding boss at the lower part of the front foot panel 7, to ensure that the plantar force of the human body can be fully loaded on the three three-dimensional force sensors to achieve accurate measurement.

[0077] The first three-dimensional force sensor 2 includes: a top cover 201, a first pressure sensor 202, a first force guide platform 203, a second force guide platform 204, a second pressure sensor 205, a ball 206, and a first base 207. The first pressure sensor 202 is attached to the upper surface of the first force guide platform 203. A groove is provided at the center of the lower surface of the top cover 201 and is coaxially fixedly connected to the first pressure sensor 202. The top cover 201 is gap-matched with the first force guide platform 203 to ensure that all pressure is collected on the first pressure sensor 202. The lower surface of the first force guide platform 203 is in an inverted pyramid shape, and each side surface thereof is in contact with a second force guide platform 204 to ensure that all collected pressure can be completely decomposed into components in four directions: front, back, left, and right. A second pressure sensor 205 is attached to each of the opposite sides, and two open grooves are provided at the bottom of the four second force guiding platforms 204. The grooves contain built-in ball bearings 206, which are embedded downwardly in the grooves at the corresponding positions of the first base 207, so that the surface of the second pressure sensor 205 is in close contact with the inner wall of the groove inside the first base 207. The second force guiding platform 204 can move along the groove direction through the rolling of the ball bearings 206, ensuring that each component force can be transmitted to the corresponding second pressure sensor 205 through the second force guiding platform 204 along the corresponding direction, thereby realizing the full collection of force.

[0078] The second three-dimensional force sensor 6 includes: a force-bearing platform 601 , a first force guide ring 602 , a first force measuring piece 603 , a support piece 604 , a second force guide ring 605 , a second force measuring piece 606 , a main control 607 and a second base 608 . Blind holes are provided on the four walls of the load-bearing platform 601. A support platform 6042 in a support member 604 is inserted to the left into the blind hole on the right side of the load-bearing platform 601 for interference fit. A first telescopic rod 6034 in a first force-measuring member 603 is inserted backward into the blind hole at the corresponding position on the front side of the load-bearing platform 601 and is fixedly connected. The above only takes one side of the middle load-bearing platform 601 as an example. The assembly relationship of the middle load-bearing platform 601 and the parts on the other side are the same, ensuring that the load-bearing platform 601 can only move in the front and rear directions but not in the left and right directions when it moves under force, so that the first force-measuring member 603 can measure the force in the front and rear directions exerted on the load-bearing platform 601. The inner wall of the first force guide ring 602 is provided with a boss and a slide rail, which are connected to the load-bearing platform 601 through two support members 604 and two first force-measuring members 603. A force measuring piece 603 is pressed into contact to ensure that the bearing platform 601 can move in the vertical direction when under pressure, so that the pressure is measured by the second force measuring piece 606. Blind holes are also provided on the four walls of the first force guide ring 602. A support platform 6042 in a support piece 604 is embedded backward in the blind hole at the corresponding position on the front side of the first force guide ring 602 with an interference fit. A first telescopic rod 6034 in a first force measuring piece 603 is embedded to the left in the blind hole at the corresponding position on the right side of the force bearing platform 601 and is fixed. The above only takes one side of the middle second force guide ring 602 as an example. The middle first force guide ring 605 has the same assembly relationship with the parts on the other side, ensuring that the first force guide ring 605 can only move in the left and right directions but not in the front and back directions when it moves under force. The inner wall of the second force guide ring 605 is provided with a boss and a slide rail, which are compacted and contacted by two first force measuring pieces 603 and two support pieces 604 to ensure that the first force guide ring 602 can move in the vertical direction. The second force measuring piece 606 is coaxially fixedly connected to the bottom center of the force bearing platform 601 through the second telescopic rod 6061 upward. The bottom of the second force measuring piece 606 is compacted and contacted with the inner upper surface of the second base 608 through the third rigid ball 6069 to ensure that the second force measuring piece 606 can slide freely in the inner groove of the second base 608, thereby ensuring the decoupling of the second force measuring piece 606 in the front, back, left and right directions. The main control 607 is fixedly connected to the corresponding position of the inner groove of the second base 608 to ensure the circuit connection and power supply of the first force measuring piece 603 and the second force measuring piece 606.

[0079] The first force measuring member 603 includes: a first rigid ball 6031 , a slide rail 6032 , a first electrode plate 6033 , a first telescopic rod 6034 , a second electrode plate 6035 and a first spring 6036 . The first spring 6036 is coaxially nested in the first telescopic rod 6034 and is fixedly connected to the corresponding position on the right side of the slide rail 6032. The other end of the first spring 6036 is fixedly connected to the corresponding position of the force-bearing platform 601, ensuring that the force-bearing platform 601 can only move left and right along the first telescopic rod 6034 when the first spring 6036 is compressed by force, and ensuring that the first spring 6036 can only be vertically compressed and stretched, that is, the left and right forces on the force-bearing platform 601 are completely converted into elastic deformation of the first spring 6036 by Hooke's theorem through the first spring 6036; the left side of the slide rail 6032 has a groove, and a first rigid ball 6031 is arranged in the groove, which is pressed and contacted with the groove at the corresponding position on the inner side of the first force guide ring 602, ensuring that when the force-bearing platform 601 is forced to move downward, it can drive the first force measuring piece 603 to move downward at the same time, so that the force in the vertical direction can be collected by the second force measuring piece 606; the first electrode plate 6033 is moved to The left coaxially embedded in the groove at the corresponding position of the slide rail 6032 is fixedly connected, and the second electrode plate 6035 is coaxially embedded in the corresponding groove on the side of the force-bearing platform 601 to the right and is fixedly connected. The first electrode plate 6033 and the second electrode plate 6035 are connected through the main control 607 wire to form a capacitor, and then form a half-bridge circuit with the corresponding capacitor in the first force measuring piece 603 on the other side of the force-bearing platform 601, and the elastic deformation of the first spring 6036 is converted into the distance between the two plates of the capacitor, so that the capacitance signal is converted into an analog signal and measured by the circuit board. The above only takes the assembly of one side of the force-bearing platform 601 and one side of the first force guide ring 602 through a first force measuring piece 603 as an example. The other side of the force-bearing platform 601 and the other side of the first force guide ring 602 are assembled in the same relationship through a first force measuring piece 603. The corresponding positions on both sides of the first force guide ring 602 and the corresponding positions on both sides of the second force guide ring 605 are respectively assembled through a first force measuring piece 603.

[0080] The support member 604 includes: a second rigid ball 6041 and a support platform 6042. Four opening grooves are distributed in a square shape at four points on the left surface of the support platform 6042, and four second rigid balls 6041 are built in the grooves, which are pressed and contacted with the boss at the corresponding position of the first force guide ring 602 to the left, and the right side of the support platform 6042 is coaxially fixedly connected with the blind hole at the corresponding position of the bearing platform 601, thereby limiting the movement of the bearing platform 601 in the left and right directions. The above only takes the assembly of the bearing platform 601 and the first force guide ring 602 through a support member 604 as an example. The other side of the bearing platform 601 is assembled with the other side of the first force guide ring 602 through a support member 604 in the same manner, and the corresponding positions on both sides of the first force guide ring 602 and the corresponding positions on both sides of the second force guide ring 605 are assembled through a support member 604 in the same manner.

[0081] The second force measuring member 606 includes: a second telescopic rod 6061 , an electrode rod 6062 , a third electrode plate 6063 , a fourth electrode plate 6064 , a sleeve 6065 , a second spring 6066 , a fifth electrode plate 6067 , a bottom plate 6068 and a third rigid ball 6069 . The second telescopic rod 6061 is coaxially interference fit with the blind hole at the bottom center of the bearing platform 601 upwards, and passes through the second spring 6066 downwards and is coaxially fixedly connected to the corresponding position in the center of the bottom plate 6068, ensuring that when the bearing platform 601 is under pressure, all the pressure is transmitted to the second spring 6066 through the top of the second telescopic rod 6061, thereby converting the pressure into elastic deformation of the second spring 6066; there are 4 square opening grooves distributed at the corresponding positions on the lower surface of the bottom plate 6068, and the third rigid ball 6069 is built in the groove, which is pressed downward with the second base 608 and simultaneously ensures that the bearing platform 601 can move in the corresponding direction when subjected to the front, back, left and right forces, thereby ensuring that the second spring 6066 always maintains vertical deformation; the upper end of the electrode rod 6062 is coaxially matched with the blind hole at the corresponding position at the lower end of the bearing platform 601, and the lower end first passes through the third electrode plate 6063 and is fixedly connected to the fourth electrode plate 6064, and the fourth electrode plate 6064 is located in the sleeve 606 5 center position, the third electrode plate 6063 is fixedly connected to the top end of the sleeve 6065, the fifth electrode plate 6067 is upwardly nested and fixedly connected to the bottom end of the sleeve 6065, and downwardly embedded in the corresponding position slot of the bottom plate 6068, so as to ensure that the electrode rod 6062, the third electrode plate 6063, the fourth electrode plate 6064, the sleeve 6065 and the fifth electrode plate 6067 are coaxially matched; the third electrode plate 6063 and the upper surface of the fourth electrode plate 6064 form a capacitor, and the lower surface of the fourth electrode plate 6064 and the fifth electrode plate 6067 form a capacitor. When the bearing platform 601 is compressed, the electrode rod 6062 drives the fourth electrode plate 6064 to move along the sleeve 6065, resulting in changes in the two capacitors here, and the changes are equal. The capacitors are connected through the wires of the main control 607 to form a half-bridge circuit, so that the capacitance signal is converted into an analog signal and then collected using the circuit board, and the deformation of the second spring 6066 is twice the change of the distance between the two electrode plates of the capacitor.

[0082] A first three-dimensional force sensor 2 and two second three-dimensional force sensors 6 are respectively built into the corresponding grooves of the rear foot sole 1 and the corresponding grooves of the front foot sole 4, and the user wears the shoe through the upper shoelaces of the rear foot panel 3 and the front foot panel 7. When the user starts walking, the weight starts to press down the rear foot panel 3 and the front foot panel 7 and is transmitted to the first three-dimensional force sensor 2 and the second three-dimensional force sensor 6. When the pressure is transmitted to the first three-dimensional force sensor 2, it is collected by the top cover 201 and then pressed on the first pressure sensor 202, and the detection of the vertical load is realized at this time. Although the movement load of the human body in the front-to-back and left-to-right directions is smaller than that in the vertical direction, the top cover 201 drives the first force guide platform 203 to press on the four second force guide platforms 204, and then transmits it to the four second pressure sensors 205, so as to realize the movement load detection in the front-to-back and left-to-right directions in the horizontal plane. For example, when the first force guide platform 203 is subjected to the front-to-back force, it will force the two second force guide platforms 204 in the front-to-back direction to slip, so that the forces collected by the corresponding two second pressure sensors 205 have a certain difference, which is the magnitude of the force in the front-to-back direction of the human body during walking. Similarly, when the first force guide platform 203 is subjected to the left-to-right force, it will cause the readings of the two second pressure sensors 205 in the left-to-right direction to have a difference, which is the magnitude of the force in the left-to-right direction of the human body during walking. When the pressure is transmitted to the second three-dimensional force sensor 6, the body weight begins to press the bearing platform 601 downward, and then the load in the vertical direction is limited by the second telescopic rod 6061 so that the second spring 6066 can only produce elastic deformation in the vertical direction, and the elastic deformation is converted into a change in the spacing between the two plates of the capacitor, and the capacitance value is measured by the half-bridge circuit, so that the detection of the vertical load can be realized. Although the motion load of the human body in the front and back and left and right directions is smaller than that in the vertical direction, the load detection of the human body in the front and back and left and right directions can be realized by the mutual cooperation of the bearing platform 601, the first force guide ring 602, the first force measuring piece 603, the support piece 604 and the second force guide ring 605. For example, when the bearing platform 601 is subjected to the front and back load, due to the cooperation of the two support pieces 604, the bearing platform 601 can only move in the front and back direction, at this time, the first spring 6036 will be elastically deformed, and then the elastic deformation is converted into a change in the spacing between the two plates of the capacitor, and then the motion load detection of the human body in the front and back direction can be realized by measuring the capacitance value. When the bearing platform 601 is subjected to loads in the left and right directions, the bearing platform 601 will drive the first force guide ring 602 to move in the left and right directions due to the pressure of the two support members 604 on the first force guide ring 602, and then the left and right movement load detection of the human body is realized through the first force measuring member 603. The present invention realizes the decoupling effect of loads in various directions through multiple groups of balls 206, the first rigid ball 6031, the second rigid ball 6041 and the third rigid ball 6069, and realizes the accurate measurement of the three-dimensional force of the sole through zeroing calibration after the initial assembly.

[0083] The wearable walking posture judgment wireless sensor system of the present invention is applicable to the identification algorithm of balance in different walking posture states, comprising the following steps:

[0084] Step 1: Collect the foot force of the user during walking;

[0085] Step 2: Collect inertial signals from the soles of the user's feet when the user is walking normally, and compare them in real time with the database of angle changes between the soles of the feet and the ground during the walking process of healthy people to determine the gait cycle of the user's body;

[0086] Collect the plantar pressure signal of the user when walking normally, compare it with the database of ground reaction force value changes during the walking process of healthy people in real time, and judge the balance of the user's gait phase;

[0087] In the identification algorithm of balance in different walking posture states of the present invention, step 1 specifically includes the following steps:

[0088] The first step is to establish a three-dimensional coordinate system with the center of the left and right ankles of the user when standing in the coronal plane of the human body as the origin and the front of the user as the positive direction of the X-axis;

[0089] In the second step, the plantar force was calculated based on 8 groups of subjects with different standard heights. The data was further standardized and the original data was subjected to multivariate regression. The final calculation formula was as follows:

[0090]

[0091] Where: F X 、F Y 、F Z It is the pressure of the sole of the foot on the ground in three axes during normal walking.

[0092] According to the above formula, the first three-dimensional force sensor 2 uses pressure sensing to select a range, taking the vertical pressure of a healthy human body on the ground during normal walking as a reference, and the pressure of the sole of the foot in the front and back and left and right directions as a supplement, so as to select a suitable pressure sensing range, and the calculation formula is as follows:

[0093]

[0094] Where: It is divided into the range of pressure sensitivity required in the X, Y and Z axis directions, and θ is the angle between the plane where the side surface of the first force guiding platform 203 is located and the horizontal plane.

[0095] According to the above formula, the stiffness of the spring used by the second three-dimensional force sensor 6 is selected according to Hooke's law, and the calculation formula is as follows:

[0096] F i =K i di (i=X,Y,Z)

[0097] Where: F i is the magnitude of the three axial forces, K i Use the spring stiffness constants for the three axial forces, d i Elastic deformation of the spring used in the three axial directions.

[0098] In the identification algorithm of the balance in different walking posture states of the present invention, step 2 specifically includes the following steps:

[0099] The first step is to use the designed plantar force measuring device to measure the three-dimensional force and inertia parameters of the plantar during walking;

[0100] Step 2: The specific calculation formula for the first three-dimensional plantar force is as follows:

[0101]

[0102] Where: F X 、F Y 、F Z They are the pressure of the sole of the foot on the ground in three axes during normal walking; F 1 F is the indication of the second pressure sensor 205 in the forward direction; 2 F is the indication of the second pressure sensor 205 in the rear direction; 3 F is the indication of the second pressure sensor 205 in the right direction; 4 F is the indication of the second pressure sensor 205 in the left direction; 5 is the indication of the first pressure sensor 202;

[0103] Step 3: The specific calculation formula for the second three-dimensional plantar force is as follows:

[0104]

[0105] Where: F X 、F Y 、F Z They are the pressure of the sole of the foot on the ground in three axes during normal walking; K i The spring stiffness coefficient used for the axial force i; K z Use the spring stiffness coefficient for the z-axis force; A i A is the cross-sectional area of ​​the electrode plate used for the axial force; z is the cross-sectional area of ​​the electrode plate used for the z-axis force; C is the capacitance; ε is the dielectric constant of air;

[0106] Step 4: Determine the specific state of the user's exercise based on the change rules of the ground support reaction force and the angle between the sole of the foot and the ground during exercise in healthy people who are comparable to the user.

[0107] In the algorithm for identifying balance in different walking postures of the present invention, the inertial sensor used in the wearable walking posture judgment wireless sensor system collects inertial parameter values ​​such as the angle of the sole of the foot to the ground during human walking at 200 Hz / s.

[0108] The wearable walking posture judgment wireless sensor system of the present invention and the identification algorithm of balance in different walking posture states can judge the specific phase in human gait and monitor the balance of human gait and walking posture through the detection of mechanical signals and inertial signals, so as to effectively take protective measures when the human body is about to become unstable; detect the three-dimensional force of the human plantar and judge the specific phase of human gait, which can provide a detection and analysis tool for sports rehabilitation robots.

[0109] The wearable walking posture judgment wireless sensor system of the present invention is designed to be suitable for use in a home environment and can be used for multiple functions. It fills the technical gap in this field under the social background of an aging population and can reduce the occurrence of a series of diseases caused by falls in the elderly.

[0110] The wearable walking posture judgment wireless sensor system of the present invention has low cost and light weight, fills the technical gap in the field of healthy human walking kinematics detection and evaluation products, reduces the expenses caused by the occurrence of diseases, and has broad market application prospects.

[0111] The wearable walking posture judgment wireless sensor system of the present invention can effectively and accurately measure the three-axis forces of plantar pressure, and identify the walking posture balance through the core of the single-chip microcomputer itself, so as to obtain the best result with the most saved resources. In addition, the Internet of Things is used to realize the switching of the sensor, and Bluetooth is used for wireless transmission of data. The structure is simple, compact and low-cost.

[0112] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A wearable walking posture judgment wireless sensor system, characterized in that: include: A rear foot sole (1), a first three-dimensional force sensor (2), a rear foot panel (3), a front foot sole (4), a pin (5), two second three-dimensional force sensors (6) and a front foot panel (7); The pin (5) passes through a through hole at a corresponding position on the front end of the rear foot panel (3), then passes through a through hole at a corresponding position on the rear end of the front foot panel (7), and then passes through a through hole at a corresponding position on the front end of the rear foot panel (3) to fit the gap, so that the rear foot panel (3) and the front foot panel (7) can rotate relative to each other; An interference fit is adopted between the lower part of the first three-dimensional force sensor (2) and the inner diameter of the circular stepped groove at the heel position on the rear foot sole (1) to fix the position of the first three-dimensional force sensor (2); The lower parts of the two second three-dimensional force sensors (6) are respectively fitted with the inner diameters of the circular stepped grooves at the positions of the first metatarsal bone and the second and third metatarsal bones on the upper surface of the forefoot sole (4) by interference fit, so as to fix the positions of the two second three-dimensional force sensors (6); The rear foot sole plate (1) and the front foot sole plate (4) are respectively provided with two grooves at the bottom, the rear foot panel (3) and the front foot panel (7) are provided with through holes at corresponding positions in the middle, and the rear foot panel (3) and the front foot panel (7) are fixedly connected by a rope; A certain gap is maintained between the upper part of the first three-dimensional force sensor (2) and the boss at the corresponding position of the lower part of the rear foot panel (3), and a certain gap is maintained between the upper parts of the two second three-dimensional force sensors (6) and the bosses at the corresponding positions of the lower part of the front foot panel (7), respectively, to ensure that the plantar force of the human body can be fully loaded onto the three three-dimensional force sensors, thereby achieving accurate measurement.

2. The wearable walking posture determination wireless sensor system according to claim 1, characterized in that: The first three-dimensional force sensor (2) comprises: a top cover (201), a first pressure sensor (202), a first force guide platform (203), four second force guide platforms (204), a second pressure sensor (205), a ball (206) and a first base (207); A first pressure sensor (202) is attached to the upper surface of the first force-guiding platform (203); a groove is provided at the center of the lower surface of the top cover (201) and is coaxially fixedly connected to the first pressure sensor (202) and is clearance-matched with the first force-guiding platform (203); the lower surface of the first force-guiding platform (203) is in the shape of an inverted pyramid, and each side surface is respectively fitted with a second force-guiding platform (204); a second pressure sensor (205) is respectively attached to the opposite side of the four second force-guiding platforms (204) respectively fitted with the first force-guiding platform (203); two open grooves are respectively provided at the bottom of the four second force-guiding platforms (204), and a ball (206) is respectively provided in each open groove, which is embedded downwardly in the groove at the corresponding position of the first base (207), so that the surface of the second pressure sensor (205) is in close compaction contact with the inner wall of the inner groove of the first base (207), and the second force-guiding platform (204) moves along the groove direction through the rolling of the ball (206).

3. The wearable walking posture determination wireless sensor system according to claim 1, characterized in that: The second three-dimensional force sensor (6) comprises: a force bearing platform (601), a first force guide ring (602), a first force measuring member (603), a support member (604), a second force guide ring (605), a second force measuring member (606), a main control (607) and a second base (608); Blind holes are respectively provided on the four walls of the bearing platform (601); the supporting platform (6042) in the supporting member (604) is inserted into the blind hole of the bearing platform (601) with interference fit; the first telescopic rod (6034) in the first force measuring member (603) is inserted into the blind hole at the corresponding position on the front side of the bearing platform (601) and fixedly connected; The inner wall of the first force guide ring (602) is provided with a boss and a slide rail which are pressed and contacted with the force bearing platform (601) through two support members (604) and two first force measuring members (603); the four walls of the first force guide ring (602) are respectively provided with blind holes, and the support platform (6042) in the support member (604) is inserted into the blind hole at the corresponding position of the first force guide ring (602) to form an interference fit; The inner wall of the second force guide ring (605) is provided with a boss and a slide rail which are pressed and contacted by two first force measuring pieces (603) and two support pieces (604); the second force measuring piece (606) is coaxially fixedly connected to the center of the bottom of the force bearing platform (601) through a second telescopic rod (6061); the second force measuring piece (606) is pressed and contacted with the inner upper surface of the second base (608) through a third rigid ball (6069), so as to ensure that the second force measuring piece (606) can slide freely in the inner groove of the second base (608); and the main control (607) is fixedly connected to the corresponding position of the inner groove of the second base (608); The first force measuring member (603) comprises: a first rigid ball (6031), a slide rail (6032), a first electrode plate (6033), a first telescopic rod (6034), a second electrode plate (6035) and a first spring (6036); the first spring (6036) is coaxially nested in the first telescopic rod (6034) and fixedly connected to a corresponding position of the slide rail (6032); the other end of the first spring (6036) is fixedly connected to a corresponding position of the force bearing platform (601) The slide rail (6032) has a groove, in which a first rigid ball (6031) is arranged, which is pressed and contacted with the groove at the corresponding position on the inner side of the first force guide ring (602); the first electrode plate (6033) is coaxially embedded in the groove at the corresponding position of the slide rail (6032) and fixedly connected; the second electrode plate (6032) is coaxially embedded in the corresponding groove on the side of the bearing platform (601) and fixedly connected; the first telescopic rod (6034) is embedded in the blind hole at the corresponding position of the first force guide ring (602) and fixedly connected; The support member (604) comprises: a second rigid ball (6041) and a support platform (6042); four opening slots are distributed in a square shape at four points on the left surface of the support platform (6042), and four second rigid balls (6041) are respectively arranged in each opening slot, which are pressed and contacted with the boss at the corresponding position of the first force guide ring (602), and the support platform (6042) is coaxially fixedly connected with the blind hole at the corresponding position of the force bearing platform (601), thereby fixing the restriction of the force bearing platform (601) in the left and right directions; The second force measuring member (606) comprises: a second telescopic rod (6061), an electrode rod (6062), a third electrode plate (6063), a fourth electrode plate (6064), a sleeve (6065), a second spring (6066), a fifth electrode plate (6067), a bottom plate (6068) and a third rigid ball (6069); the second telescopic rod (6061) is coaxially interference fit with a blind hole at the bottom center of the force bearing platform (601), passes through the second spring (6066) and is coaxially fixedly connected to a corresponding position at the center of the bottom plate (6068), and the corresponding position on the lower surface of the bottom plate (6068) has four openings distributed in a square shape. A third rigid ball (6069) is arranged in each opening groove, which is pressed and contacted with the second base (608); the upper end of the electrode rod (6062) is coaxially matched with the blind hole at the corresponding position of the lower end of the bearing platform (601); the lower end passes through the third electrode plate (6063) and is fixedly connected to the fourth electrode plate (6064); the fourth electrode plate (6064) is located at the center of the sleeve (6065); the third electrode plate (6063) is fixedly connected to the top of the sleeve (6065); the fifth electrode plate (6067) is nested upwardly and fixedly connected to the bottom end of the sleeve (6065), and is embedded downwardly in the corresponding position of the bottom plate (6068).

4. An algorithm for identifying the balance of a wearable walking posture judgment wireless sensor system in different walking posture states applicable to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1: Collect the foot force of the user during walking; Step 2: Collect inertial signals from the soles of the user's feet when the user is walking normally, and compare them in real time with the database of angle changes between the soles of the feet and the ground during the walking process of healthy people to determine the gait cycle of the user's body; The plantar pressure signal of the user's body during normal walking is collected, and the ground reaction force value change law database during the walking process of healthy people is compared in real time to determine the balance of the user's gait phase.

5. The algorithm for identifying balance in different walking postures according to claim 4 is characterized in that: Step 1 specifically includes the following steps: Step 1.1: Establish a three-dimensional coordinate system with the center of the left and right ankles of the user standing in the coronal plane as the origin and the front of the user as the positive direction of the X-axis; Step 1.2: Calculation of plantar force Based on 8 groups of subjects with different standard heights, the data was further standardized and the original data was subjected to multiple regression to obtain the following calculation formula: Where: F X 、F Y 、F Z It is the pressure of the sole of the foot on the ground in three axes during normal walking.

6. The algorithm for identifying balance in different walking postures according to claim 5, characterized in that: Step 2 also includes: selecting a range of pressure sensitivity for the first three-dimensional force sensor (2) according to the formula in step 1.2, taking the vertical pressure of a healthy human body on the ground during normal walking as a reference, and taking the pressure of the sole of the foot in the front-back and left-right directions as a supplement, so as to select a suitable pressure sensitivity range, and the calculation formula is as follows: Where: The pressure sensing range required in the X, Y and Z axis directions is divided into two types, and θ is the angle between the plane where the side surface of the first force guiding platform (203) is located and the horizontal plane.

7. The algorithm for identifying balance in different walking postures according to claim 5, characterized in that: Step 2 also includes: selecting the stiffness of the spring used by the second three-dimensional force sensor (6) according to the formula in step 1.2 and according to Hooke's law, and the calculation formula is as follows: F i =K i d i (i=X,Y,Z) Where: F i is the magnitude of the three axial forces, K i Use the spring stiffness constants for the three axial forces, d i Elastic deformation of the spring used in the three axial directions.

8. The algorithm for identifying balance in different walking postures according to claim 4, characterized in that: Step 2 specifically includes the following steps: Step 2.1: Use the wearable walking posture judgment wireless sensor system to measure the three-dimensional force and inertial parameters of the plantar during walking; Step 2.2: The specific calculation formula of the first three-dimensional plantar force is as follows: Where: F X 、F Y 、F Z They are respectively the pressure of the sole of the foot on the ground in three axes during normal walking; F1 is the indication of the second pressure sense (205) in the forward direction; F2 is the indication of the second pressure sense (205) in the backward direction; F3 is the indication of the second pressure sense (205) in the right direction; F4 is the indication of the second pressure sense (205) in the left direction; F5 is the indication of the first pressure sense (202); Step 2.3: The specific calculation formula of the second three-dimensional plantar force is as follows: Where: F X 、F Y 、F Z They are the pressure of the sole of the foot on the ground in three axes during normal walking; K i The stiffness coefficient of the spring used for the axial force i; K z Use the spring stiffness coefficient for the z-axis force; A i A is the cross-sectional area of ​​the electrode plate used for the axial force; z is the cross-sectional area of ​​the electrode plate used for the z-axis force; C is the capacitance; ε is the dielectric constant of air; Step 2.4: Determine the specific phase of the user's gait cycle and the balance in this phase based on the change pattern of the ground support reaction force and the angle between the sole of the foot and the ground during walking of a healthy person who is comparable to the user.

9. The algorithm for identifying balance in different walking postures according to any one of claims 5 to 8, characterized in that: The inertial sensor used in the wearable walking posture judgment wireless sensor system collects the inertial parameter value of the angle between the sole of the foot and the ground during human walking at 200 Hz / s.

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