Flexible sensor with multifunctional sensing function

Abstract

The utility model discloses a flexible sensor with a multifunctional sensing function. The flexible sensor with the multifunctional sensing function is arranged in a stacked mode and comprises an upper-layer flexible substrate, a lower-layer flexible substrate, a humidity sensor, a temperature sensor, a pressure sensor and a chemical sensor. According to the utility model, the electrode and the sensing active substance can be prepared on the flexible substrate in a large scale through the full-printing process, so that the cost is potentially reduced. The laminated distribution mode of the multifunctional flexible sensor is simple in structure, the occupied space is saved to a great extent, the flexible sensor develops towards the miniaturization, integration and array direction, the sensors do not interfere with one another, various human physiological signals can be monitored in real time at the same time, and the application range is wide. The method is applied to wearable biological monitoring, health management and intelligent robots.

Description

Technical Field

[0001] This utility model belongs to the field of flexible sensor technology, and specifically relates to a flexible sensor with multifunctional sensing capabilities. Background Technology

[0002] Inspired by the sensory characteristics of human skin, wearable sensing systems, utilizing sensing modules (such as pressure sensors, strain sensors, and temperature sensors), can not only acquire a wealth of information from the external environment in real time but also continuously monitor the body's physiological signals (pulse, temperature, sweat, etc.). These signals provide crucial information for health assessment, disease diagnosis, and treatment. However, due to the complexity of human physiological signals, it is often necessary to integrate multiple pieces of information simultaneously to determine a person's health status, necessitating wearable sensing systems with numerous sensing functions. Compared to single-function sensors, sensors integrating multiple functions help comprehensively monitor individual health and effectively diagnose and prevent various physiological diseases. For example, vital signs (such as heart rate, body temperature, respiratory rate, blood pressure, and blood oxygen saturation) represent the state of basic bodily functions and have significant clinical implications. Early warning systems for hospital patients integrate the values ​​of these five vital signs to make a comprehensive evaluation. Therefore, multifunctional sensors capable of converting two or more different physical quantities are an inevitable trend in the future development of sensor technology.

[0003] Distributed and stacked arrangements of different sensing components are two common methods for fabricating multifunctional flexible sensors. Although distributed structures are simple, each function requires corresponding components, resulting in excessively large sensor areas, low space utilization, and complex integration and manufacturing processes. Furthermore, the sensitivity of sensors located in the middle is limited by the obstruction of surrounding sensors. In contrast, stacked spatial arrangements can reduce the planar size of the sensor and make full use of vertical space, without the layers of sensors interfering with each other.

[0004] A major challenge in wearable sensing systems is the limited number of uses for flexible sensors, necessitating simple and inexpensive fabrication processes. Compared to traditional photolithography, printing processes, including screen printing, inkjet printing, and dispensing printing, are considered a general manufacturing technology for functional flexible electronics. Flexible sensors fabricated using printing processes offer advantages such as simple fabrication, low cost, ease of manufacturing, and miniaturization. The purpose of this invention is to develop a stacked multifunctional sensor using a fully printed process that conforms well to human skin and can be used to monitor human activity (such as pulse, temperature, and pH). This multifunctional sensor not only accurately monitors real-time changes in human physiological signals and various environmental variables but is also suitable for mass production, providing an efficient solution for developing new human-machine interfaces, intelligent robots, bionic prosthetics, and other intelligent systems. Summary of the Invention

[0005] To address the shortcomings and deficiencies of existing technologies, the purpose of this utility model is to provide a flexible sensor with multifunctional sensing capabilities.

[0006] The objective of this utility model is achieved through the following technical solution:

[0007] A flexible sensor with multiple sensing functions is arranged in a stacked manner, including an upper flexible substrate, a lower flexible substrate, a humidity sensor, a temperature sensor, a pressure sensor, and a chemical sensor.

[0008] The humidity sensor is disposed on the upper surface of the upper flexible substrate;

[0009] The temperature sensor and pressure sensor are disposed on the upper surface of the lower flexible substrate;

[0010] The chemical sensor is disposed on the lower surface of the underlying flexible substrate.

[0011] Preferably, the humidity sensor, temperature sensor, pressure sensor, and chemical sensor all include electrodes and active sensing substances, and the electrodes and active sensing substances are in contact.

[0012] Preferably, the flexible sensor with multifunctional sensing capabilities further includes wires, and the electrodes in the sensor are connected to an external circuit via the wires.

[0013] Preferably, the lower surface of the upper flexible substrate and the upper surface of the lower flexible substrate are bonded together with sealant.

[0014] Preferably, the upper flexible substrate and the lower flexible substrate are made of at least one of polyimide film, polyethylene terephthalate film and polyethylene naphthalate film.

[0015] Preferably, the humidity sensor, temperature sensor, pressure sensor, and chemical sensor are all obtained by printing active sensing materials and electrode materials, i.e., printed humidity sensor, printed temperature sensor, printed pressure sensor, and printed chemical sensor.

[0016] Preferably, the electrode material is at least one of a silver electrode and a carbon electrode.

[0017] Preferably, the humidity sensing active material of the humidity sensor is at least one of graphene oxide, tungsten oxide, molybdenum disulfide, and MXene.

[0018] Preferably, the pressure sensing active material of the pressure sensor is at least one of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) and carbon nanotubes.

[0019] Preferably, the temperature-sensing active material of the temperature sensor is at least one of reduced graphene oxide, graphene, and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid).

[0020] Preferably, the chemical sensor is a pH sensor, and its chemical sensing active substance is polyaniline.

[0021] In this invention, the upper flexible substrate encapsulates the temperature and pressure sensors; the pH sensor on the lower surface of the lower flexible substrate can directly contact human skin and be used to monitor the pH value in sweat.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] This invention discloses a flexible sensor with multifunctional sensing capabilities. Electrodes and sensing active materials can be fabricated on a flexible substrate on a large scale using a fully printed process, potentially reducing costs. The multifunctional flexible sensor features a simple stacked distribution structure, which not only saves considerable space and facilitates the miniaturization, integration, and arraying of flexible sensors, but also ensures that the sensors do not interfere with each other, enabling simultaneous real-time monitoring of multiple human physiological signals. This allows for applications in wearable biomonitoring, health management, and intelligent robots. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a flexible sensor with multifunctional sensing in the embodiment; wherein 1 is the lower flexible substrate, 2 is the upper flexible substrate, 3 is the electrode, 4 is the sensing material of the pH sensor, 5 is the sensing material of the pressure sensor, 6 is the sensing material of the temperature sensor, 7 is the sensing material of the humidity sensor, and 8 is the wire.

[0025] Figure 2 The sensing performance of the humidity sensor prepared by printing graphene oxide as the sensing active material in the example is shown.

[0026] Figure 3 The response time of the pressure sensor prepared by printing carbon nanotubes as the sensing active material in the example is shown.

[0027] Figure 4 The temperature sensor prepared by printing graphene as the sensing active material in this example demonstrates its sensing performance.

[0028] Figure 5 The pH sensor in this example demonstrates its sensing performance.

[0029] Figure 6This is a schematic diagram of the distributed arrangement of sensors in the comparative example, where 9 is a flexible substrate, 10 is an electrode, 11 is the sensing material of the pH sensor, 12 is the sensing material of the pressure sensor, 13 is the sensing material of the temperature sensor, 14 is the sensing material of the humidity sensor, and 15 is a wire. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0031] Unless otherwise specified in the embodiments of this utility model, the conditions shall be performed according to conventional conditions or conditions recommended by the manufacturer. All raw materials and reagents used, unless otherwise specified, are commercially available conventional products.

[0032] A flexible sensor with multifunctional sensing capabilities, its structure is as follows: Figure 1 As shown, it includes a lower flexible substrate 1, an upper flexible substrate 2, printed electrodes 3, a printed pH sensor sensing material 4, a printed pressure sensor sensing material 5, a printed temperature sensor sensing material 6, a printed humidity sensor sensing material 7, and wires 8.

[0033] The multifunctional flexible sensor structure includes a lower flexible substrate 1 and an upper flexible substrate 2. The printed electrodes 3 are on the upper and lower surfaces of the lower flexible substrate 1 and the upper surface of the upper flexible substrate 2. The printed humidity sensor sensing active material 7 is on the electrode 3 of the upper flexible substrate 2. The printed temperature sensor sensing active material 6 and the printed pressure sensor sensing active material 5 are on the electrode 3 on the upper surface of the lower flexible substrate 1. The printed chemical sensor sensing active material 4 is on the electrode 3 on the lower surface of the lower flexible substrate 1. The electrodes of the four sensors are connected to an external circuit through wires 8. The lower surface of the upper flexible substrate and the upper surface of the lower flexible substrate are bonded together with sealant.

[0034] The materials of the lower flexible substrate 1 and the upper flexible substrate 2 are at least one of polyimide film, polyethylene terephthalate film, and polyethylene naphthalate film.

[0035] Figure 2 The image shows the sensing performance of a humidity sensor under different humidity levels, where the printed humidity sensing active material is graphene oxide.

[0036] Figure 3 The figure shows the response time of the pressure sensor, where the printed pressure-sensing active material is carbon nanotubes.

[0037] Figure 4 The image shows the sensing performance of a temperature sensor at different temperatures, where the printed temperature-sensing active material is graphene.

[0038] Figure 5 The image shows the sensing performance of the chemical sensor at different pH levels, where the printed chemical sensing active material is polyaniline.

[0039] Figure 6 This diagram illustrates a multi-functional sensor using a distributed layout for comparison. As can be seen, under the same conditions, the distributed arrangement occupies twice the area of ​​a stacked arrangement. Additionally, when the sensor is in close contact with the skin, the pH sensor can detect the pH value of human sweat; however, at this point, the sensor is soaked in sweat, which can affect the normal operation of humidity and other sensors.

[0040] The results show that the multifunctional flexible sensor with a stacked structure provided by this invention can simultaneously detect pressure, temperature, humidity and pH signals, and has broad application prospects in wearable biological monitoring and health management.

[0041] The multifunctional flexible sensor described in the above embodiments, which is fabricated using a simple and efficient all-printing process, not only saves a great deal of space but also ensures that the sensors do not interfere with each other, demonstrating broad application potential in the wearable field.

[0042] The above embodiments are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model shall be considered equivalent substitutions and shall be included within the protection scope of the present utility model.

Claims

1. A flexible sensor having multi-functional sensing, characterized by, It adopts a stacked arrangement, including an upper flexible substrate, a lower flexible substrate, a humidity sensor, a temperature sensor, a pressure sensor, and a chemical sensor; The humidity sensor is disposed on the upper surface of the upper flexible substrate; The temperature sensor and pressure sensor are disposed on the upper surface of the lower flexible substrate; The chemical sensor is disposed on the lower surface of the underlying flexible substrate.

2. The flexible sensor with multi-functional sensing according to claim 1, wherein, The humidity sensor, temperature sensor, pressure sensor, and chemical sensor all include electrodes and active sensing substances, and the electrodes and active sensing substances are in contact. 3.The flexible sensor with multi-functional sensing of claim 1 or 2, wherein, The flexible sensor with multifunctional sensing also includes wires, through which the electrodes in the sensor are connected to an external circuit. 4.The flexible sensor with multi-functional sensing of claim 1 or 2, wherein, The lower surface of the upper flexible substrate and the upper surface of the lower flexible substrate are bonded together with sealant. 5.The flexible sensor with multi-functional sensing of claim 1 or 2, wherein, The humidity sensor is a printed humidity sensor. 6.The flexible sensor with multi-functional sensing of claim 1 or 2, wherein, The temperature sensor is a printed temperature sensor. 7.The flexible sensor with multi-functional sensing of claim 1 or 2, wherein, The pressure sensor is a printed pressure sensor. 8.The flexible sensor with multi-functional sensing of claim 1 or 2, wherein, The chemical sensor is a printed chemical sensor.

9. The flexible sensor with multi-functional sensing according to claim 2, wherein, The electrodes in the sensor are printed electrodes. 10.The flexible sensor with multi-functional sensing of claim 1 or 2, wherein, The chemical sensor is a pH sensor.

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