CN114705330B

CN114705330B - Pressure sensitive structure for measuring human body pressure distribution

Info

Publication number: CN114705330B
Application number: CN202210154858.8A
Authority: CN
Inventors: 马玉霞; 韩琳; 燕芳红; 王玉坦; 张园园; 李思君; 苏文丽
Original assignee: Lanzhou University
Current assignee: Lanzhou University
Priority date: 2020-11-03
Filing date: 2020-11-03
Publication date: 2023-02-03
Anticipated expiration: 2040-11-03
Also published as: CN114705330A; CN114563116B; CN114563116A; CN112304476B; CN112304476A

Abstract

The invention relates to a pressure sensitive structure for measuring the pressure distribution of a human body, which at least comprises a sensor array, wherein the sensor array (300) comprises at least one first sensing unit (310) for detecting pressure and at least one second sensing unit (320), and under the condition that the first sensing unit (310) and the second sensing unit (320) deform and/or the contact area changes, the deformation generated by the force or the change of the contact area with a surface layer (700) is converted into the change of resistance correspondingly, or circuit connection relations among a plurality of first sensing units (310) and/or between the first sensing units (310) and the second sensing units (320) change; pressure related information of the first sensing unit (310) is obtained based on the change in resistance, current and/or voltage. According to the invention, the second sensing unit which can be linked with the first sensing unit is used for accurately acquiring the pressure area, and the edge area with less pressure influence is accurately and sensitively characterized.

Description

Pressure sensitive structure for measuring human body pressure distribution

The invention is a divisional application of the invention patent with the application number of 202011207540.9, the application date of which is 2020, 11 and 3, and the invention name of which is a pressure sensing device for measuring the pressure injury of a human body.

Technical Field

The invention relates to the technical field of pressure injury detection, in particular to a pressure sensitive structure for measuring human body pressure distribution.

Background

Pressure injury is also called pressure ulcer and bedsore, and recent guidelines indicate that the pressure injury is caused by tissue ulceration and necrosis due to persistent ischemia, anoxia and malnutrition caused by long-term local tissue compression. For the prevention and detection of pressure injury, the objectivity of detection is increased from the first various mattresses (air cushion bed, water bed, turning pillow) to pressure test blankets, which have only relied on subjective detection (Bradon scale) for a long time.

For example, chinese patent publication No. CN105942981B discloses a human body pressure distribution measuring system, which at least includes an elastic buffer layer, a pressure measuring device, and a support member located below the elastic buffer layer; the pressure measuring device comprises a force sensitive sensor group which is loaded between the elastic buffer layer and the supporting piece and is used for measuring the pressure value of each distribution point on the lower surface of the elastic buffer layer; a signal amplification module for amplifying the sensing signals generated by the force-sensitive sensor group; the A/D converter module is used for converting the amplified sensing signal output by the signal amplification module into a digital signal; the data processing module is used for restoring the digital signals into pressure values of all distribution points on the upper surface of the elastic buffer layer, and the pressure display module is used for displaying the pressure values of all the distribution points on the upper surface of the elastic buffer layer; the force-sensitive sensor group, the signal amplification module, the A/D converter module, the data processing module and the pressure display module are sequentially connected in series; the force-sensitive sensor set is further configured to: and measuring the pressure value of each distribution point on the lower surface of the elastic buffer layer in the process that each part of the supporting piece sequentially ascends and then descends. The pressure of each distribution point on the lower surface of the elastic buffer layer is reduced to the pressure of each distribution point on the upper surface of the elastic buffer layer, so that the pressure distribution of the human body is obtained. However, the pressure measuring device provided by the patent is composed of the elastic buffer layer and the supporting piece, the mechanical performance of the pressure measuring device is limited in flexibility, the shearing force cannot be measured, the measurement accuracy can be seriously affected by folding or twisting caused by the pressure impact of a human body, the air permeability of the pressure measuring device is poor, and the pressure damage can be caused by long-term use.

For example, chinese patent publication No. CN107607233A discloses a method for measuring human body pressure distribution based on a capacitance material and an airbag matrix, which includes the following steps: 1. arranging an electrode array on a flexible material, and arranging an airbag matrix below the flexible material; 2. a human body lies on the flexible material, and capacitance signals obtained by electrode array detection positioned below the position of the human body and air bag pressure signals obtained by air bag matrix detection are collected; 3. amplifying the capacitance signal and the air bag pressure signal with a signal amplification module, and converting the amplified capacitance signal output by the signal amplification module into a digital capacitance signal and a digital air bag pressure signal; 4. and processing the digital capacitance signals to establish a human body sleeping posture image, acquiring the pressure distribution condition of each part of the human body according to the digital air bag pressure signals, and establishing the human body sleeping posture pressure image according to the acquired pressure distribution condition of each part of the human body. However, the human body pressure distribution measuring method provided by the above patent adopts an air bag mode to acquire pressure signals, the air bag acquires the pressure signals in an impact mode, long-term charging is needed, and the noise is high, so that rest of patients and other personnel can be influenced.

Based on the limitations of the pressure sensors made of rigid materials, the existing sensors for measuring the pressure distribution of human bodies adopt flexible pressure sensors which are stretchable and deformable, and the outstanding characteristics of the sensors are thin and soft. The flexible pressure sensor comprises a capacitance sensor, a resistance sensor, a piezoresistance sensor, a sensor adopting a novel material and the like. The novel material can be conductive rubber, silver nanoparticles, graphene, metal and oxide nanomaterials thereof, semiconductors and other novel sensitive materials.

For example, a direct transfer method is adopted to prepare silver nano ions on materials such as Polydimethylsiloxane (PDMS) or Polystyrene (PS) and the like as a film substrate, so that a sensitive layer film is formed. For example, flexible pressure sensors can be composed based on single-walled carbon nanotubes (SWCNTs), PDMS films, and the like.

For example, document [1] discloses a flexible mechanical sensor with a double-sided structure of a polymer substrate, and discloses a flexible mechanical sensor with a polyethyleneimine/reduced graphene oxide (PEI/rGO) as a sensitive layer, so as to prepare flexible pressure sensors with different substrate structures. The sensitivity of the sensor is improved mainly due to the fact that local strain distribution generated by the positive pattern of the sensor is enhanced, and the negative Poisson's ratio characteristic generated by the back surface of the sensor is generated by the auxetic structure. This document also discloses a flexible pressure sensing fabric based on a conductive network of silver nanowires (AgNWs).

For example, document [2] sunteng. Flexible fabric strain sensor design preparation and performance research [ D ].2020. Discloses that based on good physical properties such as tensile recovery of dust-free cloth and excellent electrical properties of reduced graphene oxide (rGO), further preparation of the flexible fabric strain sensor is realized by reducing Graphene Oxide (GO) with ascorbic acid (L-AA), and a flexible mechanical sensor with good linear strain negative response, lower hysteresis, faster response speed, lower detection limit and better repeatability is obtained.

For example, chinese patent publication No. CN111060238A discloses a method for manufacturing a resistive flexible pressure sensor, which includes: 1. providing a first flexible substrate, and etching one surface of the first flexible substrate by adopting laser to form microstructures with at least two heights; 2. forming a conductive layer on the surface of the first flexible substrate with the microstructure to obtain a first flexible substrate; 3. providing a second flexible substrate, wherein the second flexible substrate comprises a second flexible substrate and electrodes arranged on one surface of the second flexible substrate; and laminating the second flexible substrate on the first flexible substrate, and enabling the electrode to be connected with the conductive layer to obtain the resistance-type flexible pressure sensor.

However, the above-disclosed flexible pressure sensors for measuring the distribution of the body pressure all focus on parameters of the sensors regarding the accuracy of the pressure sensors, such as sensitivity, detection limit, hysteresis, sensing range, etc., but do not consider the problem of accurate monitoring of the pressure area in the distribution of the body pressure, nor consider how to evaluate the mobility and mobility of the target group according to the distribution of the body pressure. Therefore, there is a need for improvement of the prior art to accurately determine the pressure area in the pressure distribution of the human body, so as to objectively evaluate the mobility of the target person, and thus objectively and accurately prevent and detect the pressure injury.

Furthermore, on the one hand, due to the differences in understanding to those skilled in the art; on the other hand, as the inventor studies a lot of documents and patents while making the present invention, but the space is not detailed to list all the details and contents, however, this invention doesn't have these prior art features, but this invention has all the features of the prior art, and the applicant reserves the right to add related prior art in the background art.

Disclosure of Invention

In view of the deficiencies of the prior art, the present invention provides a pressure sensing device for measuring pressure injury of a human body, which at least comprises a sensor array. The sensor array comprises at least one first sensing unit and at least one second sensing unit. The first sensing unit is used for detecting pressure. The second sensing unit is used for detecting the acting force generated by the first sensing unit. The second sensing unit can detect the contact area with the surface layer through the acting force under the condition that the surface layer is deformed or not deformed. The existing pressure sensing device can only detect a small part of pressure injury generating factors, namely, the prior art focuses on the parameters of the pressure sensor in the aspects of accuracy, such as thickness, flexibility, sensitivity, detection limit, hysteresis, sensing range and the like, of the pressure sensor, the detection index only obtains the measured pressure, but the characterization of a pressure area, particularly an edge area of pressure action, is fuzzy or even cannot be characterized, the detection index based on single pressure needs to be matched with a large number of subjective indexes when evaluating the pressure injury and cannot be objectively evaluated, the prevention and detection of the pressure injury are influenced to a great extent, the pressure injury cannot be effectively controlled, and the effective help cannot be provided for reducing the medical cost and the workload of medical workers. The invention is based on the above problems, and can accurately acquire the pressure area by using the second sensing unit which can be linked with the first sensing unit in addition to the first sensing unit to detect the pressure index, and can accurately and sensitively characterize the edge area with less pressure influence. The mode of accurately and sensitively representing the edge area with small pressure influence is to pull or push the second sensing unit to deform by the acting force generated when the first sensing unit deforms. The deformation of the second sensor can transmit corresponding sensing information, and in addition, the invention utilizes the contact of the second sensor with the surface layer when the second sensor is deformed and transmits sensing mechanical information through the change of the contact area, thereby greatly improving the sensitivity. It should be noted that, generally, at the edge of the pressure acting area, the surface layer may not deform or deform less due to weak pressure, and the invention can detect the contact area with the surface layer when the surface layer does not deform or deforms less by pulling or pushing the second sensing unit, and can convert the deformation and the change of the contact area into the change of the resistance value for sensing, so as to accurately obtain the pressure area and the direction and magnitude change of the human body pressure acting, i.e. the pressure distribution of the invention not only can accurately sense the pressure area, but also can sense the magnitude and direction of the force in the pressure acting edge area. In addition, the change of the pressure area and the force and the direction of the pressure action edge area can be converted into objective indexes of the movement ability and the activity ability of the target crowd, so that the movement ability of the target crowd can be objectively evaluated, and the pressure injury can be objectively and accurately prevented and detected.

The invention also provides a pressure sensing device for measuring the pressure injury of the human body, which at least comprises a surface layer. A first sensing unit and a second sensing unit are arranged in the surface layer. At least one side of the second sensing unit, which is opposite to the surface layer, is not parallel to and perpendicular to the surface layer. The side, which is not parallel and perpendicular to the surface layer, of the second sensing unit can change an angle between the second sensing unit and the surface layer under the action of the first sensing unit.

The invention also provides a pressure sensing device for measuring pressure injury of a human body, which at least comprises a sensor array positioned between the first surface layer and the second surface layer. The sensor array includes at least a first sensing unit and a second sensing unit. The second sensing unit is configured to be capable of sensing the change of the contact area of the second sensing unit and the first surface layer and/or the second surface layer caused by the acting force of the first sensing unit on the second sensing unit and the deformation of the first surface layer and/or the second surface layer under pressure.

According to a preferred embodiment, a first connection for transmitting a force is provided between the first sensor unit and the second sensor unit. One end of the first connecting piece is connected with the first sensing unit, and the other end of the first connecting piece is connected with the second sensing unit. Preferably, one end of the first connecting piece is connected with the first sensing unit, and the other end of the first connecting piece can abut against the second sensing unit under the condition that the first sensing unit is deformed. Preferably, one end of the first connecting piece is connected with the second sensing unit, and the other end of the first connecting piece can abut against the first sensing unit under the condition that the first sensing unit is deformed. Preferably, the first connecting member may be disposed in a manner of surrounding the first and second sensing units.

According to a preferred embodiment, the first sensor unit comprises at least a first segment and a second segment. The first segment is connected/in contact with the first skin of the facing. The second segment is connected/in contact with the second surface layer of the facing layer. The cross-sectional area of the first segment in the third direction decreases/increases in the direction from the first skin to the second skin. The cross-sectional area of the second segment in the third direction decreases/increases in the direction from the second skin to the first skin. Preferably, the first segment and the second segment form an indentation/protrusion at least on a side wall in the first direction towards the second sensing unit.

According to a preferred embodiment, the first sensing unit senses the human body pressure through resistance changes caused by deformation of the first segment body and the second segment body. Under the condition that the first sensing unit bears pressure, the first section body and the second section body deform, so that the distance between the first surface layer and the second surface layer is reduced. The cross section of the fourth direction of the notch/protrusion of the first segment and the second segment extends towards the first direction. Preferably, when the first segment and the second segment are notched and subjected to pressure at least at the side wall facing the first direction of the second sensing unit, the side walls of the first segment and the second segment in the first direction can at least partially adhere to each other.

According to a preferred embodiment, the first sensing unit comprises at least a first segment in connection/contact with the first skin layer and a second segment in contact with the second skin layer. Under the condition that the first surface layer bears pressure, the second section body deforms to increase the contact area with the second surface layer. And under the condition that the pressure is greater than the deformation threshold of the second section body, the first section body deforms, so that the section area of the first section body along the third direction is increased. Under the condition that the pressure continues to increase and exceeds the deformation threshold of the first segment body, the second segment body moves along the second surface layer, so that the side wall of at least one side of the first segment body is in contact with the second surface layer.

According to a preferred embodiment, the second sensor unit comprises at least a third segment and a fourth segment. The third section body is connected/contacted with the first surface layer, and the fourth section body is connected/contacted with the second surface layer. The third segment and the fourth segment form protrusions at least on the side wall in a second direction towards the first sensing unit.

According to a preferred embodiment, when the first sensing unit transmits an acting force through the first connecting member, the third segment body and the fourth segment body are deformed to increase/decrease an included angle between the third segment body and the fourth segment body, so that a side wall of at least one side of the third segment body and/or the fourth segment body can contact a deformed or undeformed surface layer.

According to a preferred embodiment, the third segment is connected to the first skin by a second connection. And the fourth segment is connected with the second surface layer through a third connecting piece. The second connecting piece and the third connecting piece can deform along with the increase/decrease of the angle between the third section body and the fourth section body. Preferably, portions of the second and third connectors are in contact with the facing. The second and third connectors are capable of changing an area in contact with the facing as the angle between the third and fourth segments increases/decreases.

According to a preferred embodiment, at least one side wall of the third segment and/or the fourth segment is provided with at least one protrusion.

The invention also provides a pressure sensitive structure for measuring the pressure distribution of a human body, which at least comprises a sensor array, wherein the sensor array comprises at least one first sensing unit for detecting pressure and at least one second sensing unit,

under the condition that the first sensing units and the second sensing units are deformed and/or the contact areas are changed, the deformation generated by the force or the change of the contact areas with the surface layer is correspondingly converted into the change of the resistance, or the circuit connection relationship among a plurality of first sensing units and/or the first sensing units and the second sensing units is changed; pressure related information of the first sensing unit is obtained based on the change in resistance, current and/or voltage.

Preferably, the second sensing unit is configured to sense, under pressure, a force applied to the second sensing unit by the first sensing unit and a change in a contact area between the second sensing unit and the facing layer caused by deformation of the facing layer.

Preferably, at least one side of the facing layer of the second sensing unit is not parallel and perpendicular to the facing layer,

so that the side of the second sensing unit, which is not parallel and perpendicular to the surface layer, can change the angle between the second sensing unit and the surface layer under the action of the first sensing unit.

Preferably, the first sensing unit at least comprises a first segment body and a second segment body, the first segment body is connected/contacted with the first surface layer of the surface layer, the second segment body is connected/contacted with the second surface layer of the surface layer,

the first segment and the second segment are connected or integrally formed.

Preferably, the first segment and the second segment are arranged in such a way that, under the condition that the first sensing unit is under pressure, the cross section of the first segment becomes larger gradually, and certain displacement is generated in the radial direction of the first segment, so that the first sensing unit generates acting force,

the first sensing unit senses the force to the second sensing unit for evaluating the effect of the force on a local area around the second sensing unit.

Preferably, the arrangement mode of the first segment body and the second segment body at least comprises:

the cross-sectional area of the first segment body in the third direction is reduced/increased along the direction from the first surface layer to the second surface layer;

the cross-sectional area of the second segment in the third direction decreases/increases in the direction from the second skin to the first skin.

Preferably, the arrangement mode of the first segment body and the second segment body at least comprises the following steps:

the first segment and the second segment form a notch/protrusion at least on a side wall in the first direction toward the second sensing unit.

Preferably, a first connection for transmitting a force is provided between the first and second sensor units, wherein,

one end of the first connecting piece is connected with the first sensing unit, the other end of the first connecting piece is connected with the second sensing unit,

or the other end of the first sensing unit can abut against the second sensing unit under the condition that the first sensing unit is deformed;

or alternatively

One end of the first connecting piece is connected with the second sensing unit, and the other end of the first connecting piece can abut against the first sensing unit under the condition that the first sensing unit deforms;

or alternatively

The first connecting member may be disposed in a manner to surround the first and second sensing units.

Preferably, the second sensing unit comprises at least a third segment and a fourth segment, wherein,

under the condition that the first sensing unit transmits acting force through the first connecting piece, the third segment body and the fourth segment body deform to increase/reduce an included angle between the third segment body and the fourth segment body, so that the side wall of at least one side of the third segment body and/or the fourth segment body can contact a deformed or undeformed surface layer.

Preferably, the third segment is connected/in contact with the first skin layer and the fourth segment is connected/in contact with the second skin layer, wherein,

under the condition that the first sensing unit generates thrust to the second sensing unit through the first connecting piece, the angle between the third section body and the fourth section body is increased, and then the third section body and the end part of the second connecting piece at least have the condition of moving upwards, and the fourth section body and the end part of the third connecting piece at least have the condition of moving downwards, so that the second connecting piece rotates towards the first surface layer and the contact area between the second connecting piece and the first surface layer is increased.

Drawings

FIG. 1 is a schematic structural diagram of a preferred embodiment of a first sensing unit and a second sensing unit of the present invention;

FIG. 2 is a schematic structural diagram of another preferred embodiment of the first sensing unit and the second sensing unit of the present invention;

FIG. 3 is a schematic structural diagram of another preferred embodiment of the first and second sensing units of the present invention;

FIG. 4 is a schematic structural diagram of a preselected embodiment of a second sensing unit of the present invention;

FIG. 5 is a schematic view of a preferred embodiment of a sensor array of the present invention;

fig. 6 is a block diagram of a preferred embodiment of the present invention.

List of reference numerals

100: a control module; 200: a scanning module; 300: an array of sensors; 400: a signal processing module; 500: a communication module; 600: a power supply module; 700: a surface layer; 310: a first sensing unit; 320: a second sensing unit; 330: a first connecting member; 311: a first segment; 312: a second segment; 313: a fourth connecting member; 314: a fifth connecting member; 321: a third segment; 322: a fourth segment; 323: a second connecting member; 324: a third connecting member; 325: a convex portion; 710: a first surface layer; 720: a second surface layer.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings. First, relevant terms and principles are introduced.

Preferably, the flexible pressure sensor is the most important type of flexible electronic device, which can conform to any curved surface shape and generate an electrical signal under the pressure generated during electrical human body activities such as body contact and the regular physiological processes of the human body. PDMS films of various surface and layered microstructures are developed at present, and are all of nanometer and micron-sized microstructures. The facing layer 700 of the present invention may be a flexible film made of PDMS film, polyester film, or other materials. Preferably, a conductive layer can be deposited, spin-coated and cured on the surface layer 700, or a thin film having conductive properties can be used. Preferably, the conductive layer may be a conductive material such as metal, graphene oxide, or the like, or a piezoresistive material (nano force-sensitive material). Preferably, the sensor array 300 of the present invention can be made of piezoelectric material, semiconductor material, organic polymer material (conductive rubber, conductive fabric, etc.), and the like. The first sensing element 310 and the second sensing element 320 in the sensor array 300 of the present invention may also be a conductive layer that is spin coated or cured on the elastic piezoresistive material. Preferably, the size of the sensing structure such as the first sensing unit 310, the second sensing unit 320, and the first connection 330 of the present invention may be on the order of centimeters to nanometers. For micro and nano-scale microstructures, the microstructures can be manufactured by processes such as photoresist, spin coating, curing, magnetron sputtering, ICP plasma etching and the like or similar processes such as COMOS, silicon On Insulator (SOI) and the like, and the invention is not repeated.

Preferably, the sensing principle of the sensor array 300 of the present invention is as follows:

the sensing principle of the present invention is similar to that of a piezoresistive flexible pressure sensor, and the first sensing unit 310 and the second sensing unit 320 of the present invention are sensing units capable of correspondingly converting the deformation generated by the force applied to the sensing units or the change of the contact area with the surface layer 700 into the change of the resistance. When the resistance changes, the corresponding current and/or voltage also correspondingly changes, and then information sensing such as pressure, pressure area, direction and magnitude of the acting force generated by the first sensing unit 310 due to the pressure, and the range of the acting region can be obtained. Specifically, a preferred embodiment may be that the first surface 710 and the second surface 720 of the facing 700 may be conductive. The first sensing unit 310 and the second sensing unit 320 may be made of piezoresistive material, and the resistance changes when the piezoresistive material is deformed. Or the surfaces of the first and

second sensing units

310 and 320 may be conductive, and the resistance thereof changes when the contact area with the first and second skin layers 710 and 720 changes. Alternatively, the first sensing unit 310 and the second sensing unit 320 may be made of piezoresistive material, and at least the surfaces thereof may be conductive. For example, a conductive layer may be formed on the surface of the piezoresistive material, and when the first sensing unit 310 and the second sensing unit 320 are deformed and/or the contact area is changed, the resistance thereof is also changed. Through the arrangement mode, the pressure sensing device is equivalent to the parallel connection of a plurality of resistors with variable resistance values, so that the current corresponding to the resistance value change can also change. Preferably, the first skin layer 710 and the second skin layer 720 are further patterned to change the circuit connection relationship between the first sensing unit 310 and the second sensing unit 320, or between the first sensing unit 310 and other first sensing units 310 and second sensing units 320, so as to obtain the pressure related information, for example, the distribution of the first sensing unit 310 and the second sensing unit 320 as shown in fig. 5. As shown in fig. 5, a plurality of second sensing units 320 are circumferentially spaced apart from one first sensing unit 310. The first sensing units 310 are individually connected with the second sensing units 320 distributed circumferentially thereof. Preferably, the circumferentially distributed second sensing units 320 may also be connected in parallel or in series, and when the resistance value of one of the second sensing units 320 changes, the current or voltage of the one of the second sensing units changes correspondingly. Preferably, as shown in fig. 5, data of each of the first sensing unit 310 and/or the second sensing unit 320 may be acquired by scanning each of the first sensing unit 310 and/or the second sensing unit 320 one by one, respectively.

Preferably, the pressure sensing device of the present invention may also be built in, external or package the power module 600, the communication module 500, the control module 100, the signal processing module 400 and the scanning module 200. Preferably, as shown in fig. 6, the control module 100 controls the scanning module 200 to scan the sensor array 300 in a certain order. The sensor array 300 transmits the sensing signal to the signal processing module 400. The signal processing module 400 transmits the signal to the control module 100. The control module 100 transmits data to the communication module 500. The communication module 500 transmits data to the upper computer.

Preferably, the control module 100 may be a Central Processing Unit (CPU), a Micro Control Unit (MCU), a general purpose Processor, a Digital Signal Processor (DSP), an Application-Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other Programmable logic device, a transistor logic device, a hardware component, or any combination thereof. The control module 100 is used for controlling the scanning mode and timing of the scanning module 200. The control module 100 transmits the data transmitted by the signal processing module 400 to the communication module 500. The control module 100 controls the communication module 500 to transmit to the upper computer in a wireless and/or wired manner. Preferably, the scan module 200 may be composed of a plurality of analog selection switches, a decoder and a buffer. Preferably, the signal processing module 400 converts the signal output by the sensor array 300 into a voltage signal or a current signal, amplifies the voltage signal or the current signal, conditions the signal (reduces noise), and transmits the signal to the control module 100. Preferably, the signal processing module 400 includes at least an operational amplifier.

Preferably, as shown in fig. 1 to 4, the present invention provides a pressure sensing device for measuring pressure injury of a human body, comprising at least a sensor array 300. The sensor array 300 includes at least one first sensing unit 310 and at least one second sensing unit 320. The first sensing unit 310 is used to detect pressure. The second sensing unit 320 is used for detecting the acting force generated by the first sensing unit 310. The second sensing unit 320 can detect a contact area with the surface layer 700 by an acting force in a state where the surface layer 700 is deformed or not deformed. The existing pressure sensing device can only detect a small part of the pressure damage occurrence factors, namely, the prior art focuses on the parameters of the pressure sensor in terms of the accuracy of the pressure sensor, such as the thickness, the flexibility degree, the sensitivity, the detection limit, the hysteresis, the sensing range and the like, the detection index only obtains the measured pressure, the characterization of the pressure area, particularly the edge area of the pressure action, is fuzzy or even can not be characterized, the detection index based on single pressure needs to be matched with a large number of subjective indexes when evaluating the pressure damage and cannot be objectively evaluated, the prevention and the detection of the pressure damage are influenced to a great extent, the control cannot be effectively realized, and the effective help cannot be provided for reducing the medical cost and the workload of medical workers. The present invention is based on the above problems, and can precisely obtain a pressure area by using the second sensing unit 320 capable of interlocking with the first sensing unit 310 in addition to the first sensing unit 310 to detect a pressure index, and can accurately and highly sensitively represent an edge region having a small pressure influence. The way to accurately and sensitively characterize the edge region with less pressure influence is to pull or push the second sensing unit 320 to deform by the acting force generated when the first sensing unit 310 deforms. The deformation of the second sensor 320 can transmit corresponding sensing information, and in addition, the invention utilizes the contact between the second sensor 320 and the surface layer 700 when the second sensor is deformed and transmits sensing mechanical information through the change of the contact area, thereby greatly improving the sensitivity. It should be noted that, generally, at the edge of the pressure acting area, because the pressure is weak, the surface layer 700 may not deform or deform less, the second sensing unit 320 may be pulled or pushed to detect the contact area between the surface layer 700 and the surface layer 700 when the surface layer 700 does not deform or deforms less, and the change of the deformation and the contact area may be converted into the change of the resistance value to sense, so that the pressure area and the direction and magnitude change of the human body pressure acting may be accurately obtained, that is, the pressure distribution of the present invention may not only accurately sense the pressure area, but also sense the magnitude and direction of the force in the edge area where the pressure acts. In addition, the change of the pressure area and the force and the direction of the pressure action edge area can be converted into objective indexes of the movement ability and the activity ability of the target crowd, so that the movement ability of the target crowd can be objectively evaluated, and the pressure injury can be objectively and accurately prevented and detected.

Preferably, the pressure sensing device includes at least a facing 700. Disposed within the facing 700 are a first sensing unit 310 and a second sensing unit 320, as shown in fig. 1-3. At least one side of the facing layer 700 opposite the second sensing unit 320 is not parallel and perpendicular to the facing layer 700, as shown in fig. 1 to 3. The side of the second sensing unit 320 that is not parallel and perpendicular to the surface layer 700 can change the angle with the surface layer 700 under the force of the first sensing unit 310. By the arrangement, the non-parallel and non-perpendicular side of the second sensing unit 320 and the surface layer 700 enables the contact area of the second sensing unit 320 and the surface layer 700 to be changed, and the direction and the magnitude of the force of the edge on which the pressure acts can be obtained through the change. In addition, the edge of the region where the pressure is applied is generally weak and the surface layer 700 may not be deformed, and the force applied by the first sensing unit 310 causes the deformation of the second sensing unit 320 and the double change of the contact area, thereby significantly improving the sensing sensitivity to the edge force and sensing the change of the force in the region even though the surface layer 700 is not changed.

Preferably, the pressure sensing device includes at least the sensor array 300 positioned between the first skin 710 and the second skin 720. The sensor array 300 includes at least a first sensing unit 310 and a second sensing unit 320. The second sensing unit 320 is configured to sense a change in a contact area of the second sensing unit 320 and the first skin layer 710 and/or the second skin layer 720, which is caused by a combination of an acting force of the first sensing unit 310 on the second sensing unit 320 and a deformation of the first skin layer 710 and/or the second skin layer 720 under a pressure. On the basis of increasing the sensing sensitivity of the edge force of the pressure action area, the area where the pressure acts and the direction and the size of the force of the pressure acting on the area can be accurately obtained, and further the movement capacity and the activity capacity of a target crowd can be obtained or evaluated through the change of the area, the size and the direction of the pressure, so that a data basis is provided for objective and accurate evaluation of the pressure injury.

Preferably, as shown in fig. 1 to 3, a first connection 330 for transmitting an acting force is provided between the first sensing unit 310 and the second sensing unit 320. The first connector 330 has one end connected to the first sensing unit 310 and the other end connected to the second sensing unit 320. Preferably, one end of the first connecting member 330 is connected to the first sensing unit 310, and the other end can abut against the second sensing unit 320 when the first sensing unit 310 is deformed. Preferably, one end of the first connecting member 330 is connected to the second sensing unit 320, and the other end can abut against the first sensing unit 310 under the condition that the first sensing unit 310 is deformed. Preferably, as shown in fig. 3, the first connector 330 may be disposed in a manner of surrounding the first and

second sensing units

310 and 320. Preferably, the first connector 330 needs to have a certain rigidity to ensure the transmission of force. With this arrangement, the first sensing unit 310 can transmit a pulling force or a pushing force to the second sensing unit 320. Preferably, the first sensing unit 310 shown in fig. 1 is capable of generating a pushing force to the second sensing unit 320. As shown in fig. 2, the cross-section of the first sensing unit 310 is increased by the pressure, thereby generating a tensile force to the second sensing unit 320. As shown in fig. 3, under the action of the pressure, the second segment 312 of the first sensing unit 310 moves in the opposite direction of the first direction, i.e., the second direction, so as to generate a pulling force on the second sensing unit 320.

Preferably, as shown in fig. 1 and 2, the first sensing unit 310 includes at least a first segment 311 and a second segment 312. The first segment 311 is connected/in contact with the first skin 710 of the facing 700. The second segment 312 is attached to/in contact with the second skin 720 of the facing layer 700. Preferably, first segment 311 and second segment 312 are connected. Or the first segment 311 and the second segment 312 are integrally formed. Preferably, first segment 311 may be connected to first skin 710 by fourth connector 313. Second segment 312 may be connected to second skin 720 via fifth connection 314. By the arrangement mode, the difficulty of the manufacturing process can be reduced, and the mechanical property of the first sensor 310 can be improved.

Preferably, as shown in fig. 1 and 2, the cross-sectional area of the first segment 311 in the third direction decreases/increases in the direction from the first skin 710 to the second skin 720. Preferably, the third direction may be a direction perpendicular to the first sensing unit 310. The third direction cross-sectional area of the second segment 312 decreases/increases in the direction from the second skin 720 to the first skin 710. Preferably, the first segment 311 and the second segment 312 form notches/protrusions at least on the side walls in the first direction facing the second sensing unit 320, as shown in fig. 1 and 2. Preferably, the first sensing unit 310 may be circular, directional, or irregular in shape. Through the above arrangement, under the condition that the first sensing unit 310 is under pressure, the cross sections of the first segment 311 and the second segment 312 become larger gradually, and then certain displacement is generated in the radial direction, so as to generate an acting force, and the influence of the pressure on the surrounding area can be evaluated by sensing the acting force to the second sensing unit 320. For example, in the case that the first connecting member 330 is connected to the first sensing unit 310 and the second sensing unit 320 at two ends, respectively, the first connecting member 330 may be configured to have certain elasticity and rigidity, and only under a certain applied force, the first connecting member 330 pushes/pulls the second sensing unit 320 after being deformed to the limit. Alternatively, the first connecting member 330 has no elasticity, and the other end of the first connecting member 330 is spaced from the second sensing unit 320 by a certain distance, and only after the first sensing unit 310 is deformed to a certain degree, the first connecting member will abut against the second sensing unit 320, so as to push/pull the second sensing unit 320. At least the range of the pressure acting area of the first sensing unit 310 can be adjusted by the deformation threshold of the first connecting member 330 itself or the distance between the first connecting member 330 and the second sensing unit 320.

According to a preferred embodiment, the first sensing unit 310 senses the human body pressure through the resistance change caused by the deformation of the first segment 311 and the second segment 312. Under the condition that the first sensing unit 310 is under pressure, the first segment 311 and the second segment 312 deform so that the distance between the first surface layer 710 and the second surface layer 720 is reduced. The fourth direction cross section of the notches/projections of the first segment 311 and the second segment 312 extends in the first direction. Preferably, the fourth direction may be a direction perpendicular to the surface layer 700. Preferably, in a case where the first segment 311 and the second segment 312 are notched and subjected to pressure at least at the side wall in the first direction facing the second sensing unit 320, the side walls of the first segment 311 and the second segment 312 in the first direction can at least partially fit each other, as shown in fig. 1. Through this arrangement, as shown in fig. 1, the first segment 311 and the second segment 312 of the first sensing unit 310 can be attached to each other, so that the conductive area after attachment is increased, and the variation range of the first sensing unit 310 is further improved under the dual effects of deformation and area. In addition, in the case that the pressure does not act vertically, as in the embodiment shown in fig. 1, the displacement of the notch variation can be further aggravated, that is, the radial displacement of the first segment 311 and the second segment 312 can be increased, and the acting force applied to the second sensing unit 320 can be aggravated, so that the second sensing unit 320 can sense the acting force applied to the surrounding area in different application directions of the pressure.

Preferably, as shown in fig. 3, the first sensing unit 310 includes at least a first segment 311 connected/contacted with the first skin 710 and a second segment 312 contacted with the second skin 720. Under the pressure of the first skin 710, the second segment 312 deforms to increase the contact area with the second skin 720. In the case that the pressure is greater than the deformation threshold of the second segment 312, the first segment 311 deforms such that the cross-sectional area of the first segment 311 in the third direction increases. In the event that the pressure continues to increase beyond the deformation threshold of the first segment 311, the second segment 312 moves along the second skin 720 such that at least one side wall of the first segment 311 contacts the second skin 720. Through the arrangement mode, sensing is carried out through deformation and contact area change in different stages, so that pressure calibration and adjustment of the pressure sensing range corresponding to conversion are facilitated. Moreover, as shown in fig. 2, when the second segment 312 slides, the pulling force generated by the second segment on the first connecting member 330 is increased, so as to amplify the acting force of the first sensing unit 310 on the second sensing unit 320, thereby improving the sensitivity of the second sensing unit 320.

Preferably, as shown in fig. 1 to 4, the second sensing unit 320 includes at least a third segment 321 and a fourth segment 322. The third segment 321 is connected to/in contact with the first skin 710. The fourth block 322 is connected/in contact with a second skin 720. The third segment body 321 and the fourth segment body 322 form protrusions at least at sidewalls in the second direction toward the first sensing unit 310.

According to a preferred embodiment, in case that the first sensing unit 310 transmits a force through the first connecting member 330, the third segment 321 and the fourth segment 322 are deformed to increase/decrease an included angle between the third segment 321 and the fourth segment 322, so that at least one side of the third segment 321 and/or the fourth segment 322 can contact the deformed or undeformed surface layer 700. With this arrangement, when the surface layer 700 is deformed, the third segment 323 and the fourth segment 324 are not parallel or perpendicular to the surface layer 700, and therefore can be in contact with at least the surface layer 700, and the magnitude and direction of the force applied to the edge region by the pressure can be obtained from the change in resistance due to the change in the area of contact. Under the condition that the surface layer 700 is not deformed, the third segment 323 and the fourth segment 324 can be deformed under the action of the first connecting piece 330, and can move towards the first surface layer 710 and/or the second surface layer 720 to be in contact with the first surface layer 710 and/or the second surface layer 720, so that the magnitude and the direction of the acting force of the pressure on the surrounding area can be obtained through the resistance value change caused by the contact area.

Preferably, third segment 321 is connected to first skin 710 by second connector 323. The fourth segment 322 is connected to the second skin 720 by the third connecting member 324. With this arrangement, the second and

third coupling members

323 and 324 can be deformed as the angle between the third and

fourth bodies

321 and 322 increases/decreases. Preferably, the second and third connecting

members

323 and 324 may be square or round-like, as shown in fig. 2 and 3. Preferably, as shown in fig. 1, portions of the second and third connecting

members

323 and 324 are in contact with the facing 700. The second and

third coupling members

323 and 324 may be coupled to the cover 700 by elastic members. The second and

third coupling members

323 and 324 can change an area contacting the face layer 700 as the angle between the third and

fourth segments

321 and 322 increases/decreases. Preferably, as shown in fig. 1, when the first sensing unit 310 generates a pushing force on the second sensing unit 330 through the first connecting member 330, an angle between the third segment 321 and the fourth segment 322 is increased, and further, at least the end portions of the third segment 321 and the second connecting member 323 move upward, and at least the end portions of the fourth segment 322 and the third connecting member 324 move downward, so that the second connecting member 323 rotates toward the first skin 710 and a contact area with the first skin 710 is increased. The third connecting member 324 rotates toward the second skin 720 and the contact area with the second skin 720 becomes larger.

Preferably, as shown in fig. 4, at least one side wall of the third segment 321 and/or the fourth segment 322 is provided with at least one protrusion 325. With this arrangement, the convex portion 325 is deformed under the action of the surface layer 700, so that the contact area with the surface layer 700 can be increased, and the sensitivity of the second sensing unit 320 can be further improved.

The present specification encompasses multiple inventive concepts and the applicant reserves the right to submit divisional applications according to each inventive concept. The present description contains a plurality of inventive concepts such as "preferably", "according to a preferred embodiment" or "optionally" each indicating that the respective paragraph discloses a separate concept, the applicant reserves the right to apply for divisional applications according to each inventive concept.

It should be noted that the above-mentioned embodiments are exemplary, and that those skilled in the art, having benefit of the present disclosure, may devise various arrangements that are within the scope of the present disclosure and that fall within the scope of the invention. It should be understood by those skilled in the art that the present specification and figures are illustrative only and are not limiting upon the claims. The scope of the invention is defined by the claims and their equivalents.

Claims

1. A pressure sensitive structure for measurement of the pressure distribution in a human body, characterized by at least a sensor array (300),

the sensor array (300) comprises at least one first sensor unit (310) for detecting a pressure and at least one second sensor unit (320),

in case of deformation and/or change of contact area of the first sensing unit (310) and the second sensing unit (320),

the deformation caused by the force or the change of the contact area with the surface layer (700) is converted into the change of the resistance or

The circuit connection relation between a plurality of first sensing units (310) and/or between the first sensing units (310) and second sensing units (320) is changed;

acquiring pressure related information of the first sensing unit (310) based on the change of the resistance, the current and/or the voltage;

the first sensing unit (310) at least comprises a first section body (311) and a second section body (312), the first section body (311) is connected with/contacted with a first surface layer (710) of the surface layer (700), the second section body (312) is connected with/contacted with a second surface layer (720) of the surface layer (700),

the first segment (311) and the second segment (312) are connected, or the first segment (311) and the second segment (312) are integrally formed.

2. The pressure-sensitive structure for human body pressure distribution measurement according to claim 1, wherein the second sensing unit (320) is configured to sense the acting force of the first sensing unit (310) on the second sensing unit (320) under pressure and the change of the contact area of the second sensing unit (320) and the facing layer (700) caused by the deformation of the facing layer (700).

3. The pressure-sensitive structure for human body pressure distribution measurement according to claim 1 or 2, wherein at least one side of the second sensing unit (320) facing the face layer (700) is not parallel and perpendicular to the face layer (700),

so that the side of the second sensing unit (320) which is not parallel and perpendicular to the surface layer (700) can change the angle with the surface layer (700) under the action of the first sensing unit (310).

4. The pressure sensitive structure for measurement of human body pressure distribution of claim 1,

the first section body (311) and the second section body (312) are arranged in a way that the cross section of the first section body is gradually enlarged and certain displacement is generated in the radial direction under the condition that the first sensing unit (310) bears pressure, so that the first sensing unit (310) generates acting force,

the first sensing unit (310) senses the force to the second sensing unit (320) for evaluating the effect of the force on its surrounding area.

5. The pressure sensitive structure for measurement of human body pressure distribution according to claim 1, wherein the first segment (311) and the second segment (312) are arranged in a manner comprising at least:

the cross-sectional area of the first segment (311) in the third direction decreases/increases in the direction from the first skin (710) to the second skin (720);

the cross-sectional area of the second segment (312) in the third direction decreases/increases in the direction from the second skin (720) to the first skin (710).

6. Pressure sensitive structure for measurement of the distribution of human body pressure according to claim 1, characterized in that the first segment (311) and the second segment (312) are arranged in a way comprising at least:

the first segment (311) and the second segment (312) form indentations/protrusions at least at the side walls in the first direction towards the second sensing unit (320).

7. The pressure sensitive structure for human body pressure distribution measurement according to claim 1,

a first connection (330) for transmitting a force is arranged between the first sensor unit (310) and the second sensor unit (320), wherein,

one end of the first connecting member (330) is connected with the first sensing unit (310), and the other end is connected with the second sensing unit (320),

or the other end can abut against the second sensing unit (320) under the condition that the first sensing unit (310) is deformed;

or alternatively

One end of the first connecting piece (330) is connected with the second sensing unit (320), and the other end of the first connecting piece can abut against the first sensing unit (310) under the condition that the first sensing unit (310) is deformed;

or

The first connection member (330) may be disposed in a manner of surrounding the first and second sensing units (310, 320).

8. Pressure sensitive structure for human body pressure distribution measurement according to claim 7, wherein the second sensing unit (320) comprises at least a third segment (321) and a fourth segment (322), wherein,

under the condition that the first sensing unit (310) transmits acting force through the first connecting piece (330), the third section body (321) and the fourth section body (322) deform to increase/decrease the included angle between the third section body (321) and the fourth section body (322), so that the side wall of at least one side of the third section body (321) and/or the fourth section body (322) can contact the deformed or undeformed surface layer (700).

9. Pressure sensitive structure for human body pressure distribution measurement according to claim 8, wherein the third segment (321) is connected/in contact with a first skin (710) and the fourth segment (322) is connected/in contact with a second skin (720), wherein,

when the first sensing unit (310) generates a pushing force on the second sensing unit (320) through the first connecting piece (330), the angle between the third segment body (321) and the fourth segment body (322) is increased, further, at least the end parts of the third segment body (321) and the second connecting piece (323) move upwards, and at least the end parts of the fourth segment body (322) and the third connecting piece (324) move downwards, so that the second connecting piece (323) rotates towards the first surface layer (710) and the contact area between the second connecting piece and the first surface layer (710) is increased.