Intelligent glove based on piezoresistive pressure sensor

Abstract

The invention provides an intelligent glove based on piezoresistive pressure sensors. The intelligent glove comprises a glove body, a plurality of pressure sensors, a steel wire and a main control board, the plurality of pressure sensors are distributed in each detection area of the glove body; each pressure sensor consists of a flexible pressure sensor and a rigid gasket; the rigid gasket is stacked at a sensitive point position of the flexible pressure sensor; the pressure sensor is connected with the main control board through a steel wire. The steel wire is connected to the glove body in the mode that the steel wire vertically penetrates through the material of the glove body in a penetrating mode, and the effect of being sewn in the glove body is achieved. A silica gel film wraps the periphery of the steel wire. When the glove is used for a touch pressure test with higher intensity, the accuracy of signal measurement can be ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of human-computer interaction equipment, and in particular to a smart glove based on a piezoresistive pressure sensor. Background Art

[0002] With the continuous development of intelligent sensing technology, the research and development of wearable sensing devices has become a research hotspot. Among them, wearable smart gloves that integrate flexible sensing technology and machine touch have broad application prospects. In clinical medicine, wearable gloves can be used to assist doctors in achieving more accurate tactile perception and completing more precise surgical operations.

[0003] In industrial production, engineers can use wearable interactive devices to assemble equipment with high precision. In some special application scenarios, such as exoskeleton development, smart gloves can sense external force changes to provide data support for exoskeleton design, and in areas with serious safety hazards such as nuclear power plants, smart gloves can be used to remotely control equipment operation to ensure personnel safety.

[0004] However, in some special scenarios, the smart gloves are subjected to relatively strong forces, and the existing flexible sensors and copper wires are not suitable for use in these scenarios.

[0005] Taking wires as an example, in most existing smart tactile pressure sensing gloves, the connection between the pressure sensor and the main control chip is generally made of copper wires. As the external pressure increases, such as when doing lifting and other actions, the stretching of the gloves may cause the copper wires to deform or break. On the one hand, this limits the range of motion of the tester's hands, and on the other hand, it causes deviation or failure in signal measurement, resulting in the gloves being unable to perform higher-intensity tactile pressure tests. Moreover, the sensors and wires are only arranged on the surface of the gloves by adhesion, which makes the coupling degree of the entire system insufficient, and may cause the sensor part to separate from the glove part.

[0006] In addition, for flexible sensors, their flexible surfaces are difficult to cope with the impact of high-intensity pressure, making them easily damaged. Summary of the invention

[0007] In view of this, the present invention provides a smart glove based on a piezoresistive pressure sensor, which can ensure the accuracy of signal measurement when the glove is subjected to a higher intensity tactile pressure test.

[0008] In order to solve the above technical problems, the present invention is implemented as follows.

[0009] A smart glove based on a piezoresistive pressure sensor, comprising: a glove body, a plurality of pressure sensors, a steel wire and a main control board;

[0010] Multiple pressure sensors are distributed in various detection areas of the glove body; each pressure sensor is composed of a flexible pressure sensor and a rigid gasket; the rigid gasket is stacked at the sensitive point of the flexible pressure sensor;

[0011] The pressure sensor is connected to the main control board through a steel wire; the steel wire is connected to the glove body by inserting the glove body material up and down, forming an effect of being sewn into the glove body; the steel wire is wrapped with a silicone film.

[0012] Preferably, the flexible pressure sensor adopts a flexible pressure sensor array, and the rigid gasket is arranged on the sensitive point corresponding to each electrode.

[0013] Preferably, one rigid spacer covers at least 2 sensitive points.

[0014] Preferably, the flexible pressure sensor is formed by stacking multiple layers of materials, including, from bottom to top, a first flexible substrate layer, a first electrode film layer, a pressure-sensitive film layer, a second electrode film layer, and a second flexible substrate layer.

[0015] Preferably, the rigid gasket is a polymethyl methacrylate (PMMA) gasket.

[0016] Preferably, the pressure sensor is adhered to the surface of the glove by silicone glue.

[0017] Preferably, the rigid gasket is fixed on the surface of the flexible pressure sensor by gluing.

[0018] Preferably, there are 13 pressure sensors, and their layout positions include: the first pulp of the index finger, middle finger, ring finger and little finger; the third pulp of the index finger, middle finger, ring finger and little finger; the metacarpophalangeal joints corresponding to the index finger, middle finger, ring finger and little finger; and the first pulp of the thumb.

[0019] Preferably, the diameter of the steel wire is 0.45 mm; the thickness of the coated silicone film is 0.5 mm.

[0020] Preferably, the silicone film is prepared by mixing polydimethylsiloxane PDMS and a curing agent in a mass ratio of 9:1, vacuum degassing the mixture until no bubbles appear, pouring it into an aluminum alloy mold, heating and curing it, and peeling off the mold after cooling to obtain the silicone film.

[0021] Beneficial effects:

[0022] (1) The present invention replaces the copper wire with a steel wire, whose Young's modulus and tensile strength are much higher than those of ordinary copper wires. The steel wire is not easily damaged during hand activities. Under the same force conditions, the strength of the steel wire can ensure stable signal transmission and can support higher-intensity tactile pressure testing.

[0023] (2) The wire routing method of the present invention adopts a sewing method of upper and lower routing, and the wiring is routed inside the glove, so that the wire is tightly combined with the fabric, and it is not easy to separate the sensing part from the glove part, thereby improving the firmness and reliability of the entire system. At the same time, the internal routing can isolate the wire from the external environment of the glove, further protecting the transmission of the signal, and can support higher-intensity tactile pressure testing.

[0024] (3) The flexible pressure sensor of the present invention is provided with a rigid gasket, which evenly distributes the pressure received on the sensor, thereby improving the measurement accuracy and protecting the pressure sensor.

[0025] (4) In a preferred embodiment, the electrodes in the flexible pressure sensor are arranged in an array, and a rigid gasket is set at the sensitive point corresponding to each electrode. The high-density array of array-type flexible pressure sensors with rigid contacts can overcome the shortcomings of poor adaptability and accuracy affected by the pressure area brought by a single rigid pressure sensor. When the sensing position where the rigid contact is located is subjected to a large bend, it does not bend or stretch, thereby overcoming the output error caused by bending and stretching, and ensuring the accuracy of the sensor measurement.

[0026] (5) A rigid gasket can cover multiple electrodes, and the force direction of the sensor can be calculated by the different pressures at each sensing point.

[0027] (6) The conductive wire of the present invention is wrapped with a silicone film, which isolates the steel wire from the outside world to prevent the signal from being interfered with. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is the overall structure diagram of the smart glove of the present invention.

[0029] Figure 2 This is the internal circuit diagram of the smart glove of the present invention.

[0030] Figure 3 It is a cross-sectional view of a flexible pressure sensor with rigid contacts in the smart glove of the present invention.

[0031] Figure 4 It is a cross-sectional view of another flexible pressure sensor with rigid contacts according to the present invention.

[0032] Figure 5 The bending diagram of the present invention with a rigid contact array is compared with that of the existing flexible contacts.

[0033] Figure 6 This is a control block diagram of the smart gloves of the present invention.

[0034] Figure numerals: 1-pressure sensor; 2-glove body; 3-steel wire; 4-main control board; 11-first flexible base layer; 12-first electrode film layer; 13-pressure-sensitive film layer; 14-second electrode film layer; 15-second electrode film layer; 16, 17-rigid gaskets. DETAILED DESCRIPTION

[0035] The present invention provides an intelligent glove based on a piezoresistive pressure sensor, which has three characteristics: first, the pressure sensor is connected to the main control board through a steel wire, and the steel wire is used to replace the copper wire, which can withstand higher-intensity pressure, is not easily damaged during hand activities, and can support higher-intensity tactile pressure tests.

[0036] Secondly, the wire routing method adopts the sewing method of upper and lower routing, and the wiring is routed inside the glove, so that the wire and the fabric are closely combined, and it is not easy to separate the sensing part and the glove part, which improves the firmness and reliability of the whole system. At the same time, the internal routing can isolate the wire from the external environment of the glove, further protecting the signal transmission, and can support higher intensity tactile pressure testing.

[0037] Third, the pressure sensor on the smart glove is composed of a flexible pressure sensor and a rigid gasket. The rigid gasket evenly distributes the pressure on the sensor, improving the measurement accuracy and protecting the pressure sensor.

[0038] The present invention is described in detail below with reference to the accompanying drawings and embodiments.

[0039] like Figure 1 , 2 As shown, the smart glove based on the piezoresistive pressure sensor of the present invention, for a single glove, specifically includes: a pressure sensor 1, a glove body 2, a signal transmission wire 3, and a main control board 4.

[0040] The pressure sensors 1 are distributed in various detection areas of the glove body 2. Preferably, the distribution positions can be selected as follows: Figure 1 13 positions as shown. Among them, 12 sensors are distributed on the first and third finger webs and corresponding metacarpophalangeal joints of the index finger, middle finger, ring finger and little finger, and the 13th sensor is arranged on the first finger web of the thumb. Preferably, the pressure sensor is adhered to the surface of the glove by silicone glue to make it fully fit.

[0041] In one embodiment, the pressure sensor uses a flexible pressure sensor and a rigid gasket to form a flexible pressure sensor with rigid contacts. The rigid gasket is stacked on the flexible pressure sensor. The material of the rigid gasket is selected to be a material that is not easily deformed or deformed when subjected to external force. If measured by stiffness, it must reach the GPa level. Specifically, high molecular polymers such as polyethylene, polypropylene, nylon, etc. can be used, and organic glass, metal, etc. can also be selected. Preferably, polymethyl methacrylate (PMMA) has a stiffness of about 3GPa. Polymethyl methacrylate (PMMA) material is preferred. The stacking method can be adhesive. For example, laser processing of polymethyl methacrylate material with double-sided tape is used to obtain a rigid gasket, which is adhered to the pressure-sensitive point of the flexible pressure sensor. The rigid gasket faces the contact surface of the object.

[0042] Flexible pressure sensors can adopt multi-layer structures. Figure 4 As shown, it includes, from bottom to top, a first flexible substrate layer 11 , a first electrode film layer 12 , a pressure-sensitive film layer 13 , a second electrode film layer 14 , a second flexible substrate layer 15 and a rigid gasket 16 .

[0043] Preferably, the first flexible substrate layer 11 may also be connected to a rigid gasket 17, and the rigid gasket on this side can better concentrate the force on the force sensitive area. The shape of the rigid gasket may be circular or square. In this embodiment, an example of a circular rigid gasket is given, which has a diameter of 10 mm, a thickness of 1 mm, and is made of PMMA.

[0044] Figure 4 A more preferred flexible pressure sensor with rigid contacts is shown. The electrodes in the flexible pressure sensor are arranged in an array, and rigid gaskets are set at the sensitive points corresponding to each electrode. The high-density array of array-type flexible pressure sensors with rigid contacts can overcome the shortcomings of poor adaptability and accuracy affected by the pressure area brought by a single rigid pressure sensor. The sensing position where the rigid contact is located does not bend or stretch when subjected to a large bend, such as Figure 5 As shown, the output error caused by bending and stretching is overcome, ensuring the accuracy of sensor measurement.

[0045] Furthermore, a rigid gasket can cover multiple electrodes. Through the different pressures at each sensing point, the force direction of the sensor can be calculated, and then the pressure calculation can be corrected, ensuring the mechanical accuracy of the sensor during use.

[0046] The pressure sensor can be attached to the surface of the glove using silicone glue.

[0047] The signal transmission wire 3 of the pressure sensor is used to connect the pressure sensor and the main control board 4 . Figure 2Each line in the figure represents a pair of transmission lines, which are connected to the two pads of the pressure sensor, and the pressure sensor is connected in series to the circuit. The signal transmission wire 3 is a steel wire, and the outer surface of the steel wire is wrapped with a silicone film. The silicone film isolates the steel wire from the outside to prevent the signal from being interfered. The steel wire is connected to the glove body by inserting the glove body material up and down, forming an effect of sewing into the glove body. The sewing method makes the wire and the glove more closely integrated, making the entire system more solid and reliable.

[0048] In one example, the diameter of the steel wire is 0.45 mm; the thickness of the coated silicone film is 0.5 mm. The silicone film is prepared by mixing polydimethylsiloxane PDMS and a curing agent in a mass ratio of 9:1, vacuum degassing the mixture until no bubbles appear, pouring it into an aluminum alloy mold, heating and curing it, and peeling off the mold after cooling to obtain the silicone film.

[0049] The main control board 4 includes a voltage divider module, an acquisition module, a main control module, a battery module and a wireless communication module. The voltage divider module adopts a voltage follower type voltage divider circuit to convert the resistance change of the pressure sensor into a voltage change, which is convenient for measurement; the acquisition module is connected to the voltage divider module to convert the analog signal into a digital signal and send it to the main control module; the acquisition module can use the ADC built into the main control chip. The main control module, for example, adopts an STM32 series chip, which converts the measured voltage value into a pressure value, distinguishes the pressure position at the same time, and controls the wireless communication module to transmit the data to the host computer. The battery module is a 3.3V lithium battery, which is used to power the entire main control board. The wireless communication module is a Bluetooth module or a wired transmission module, which is used to conveniently transmit the collected data to the host computer.

[0050] The above specific embodiments only describe the design principle of the present invention. The shapes and names of the components in the description may be different and are not limited. Therefore, those skilled in the art in the field of the present invention may modify or replace the technical solutions recorded in the above embodiments; and these modifications and replacements do not deviate from the creative purpose and technical solutions of the present invention and should all fall within the protection scope of the present invention.

Claims

1. A smart glove based on a piezoresistive pressure sensor, characterized in that: include: The glove body, multiple pressure sensors, steel wires and main control board; Multiple pressure sensors are distributed in various detection areas of the glove body; Each pressure sensor is composed of a flexible pressure sensor and a rigid gasket; the rigid gasket is stacked at the sensitive point of the flexible pressure sensor; The pressure sensor is connected to the main control board through a steel wire; the steel wire is connected to the glove body by inserting the glove body material up and down, forming an effect of being sewn into the glove body; the steel wire is wrapped with a silicone film.

2. The smart glove according to claim 1, characterized in that: The flexible pressure sensor adopts a flexible pressure sensor array, and the rigid gasket is arranged on the sensitive point corresponding to each electrode.

3. The smart glove according to claim 2, characterized in that: A rigid spacer covers at least 2 sensitive points.

4. The smart glove according to any one of claims 1 to 3, characterized in that: The flexible pressure sensor is formed by stacking multiple layers of materials, including, from bottom to top, a first flexible substrate layer, a first electrode film layer, a pressure-sensitive film layer, a second electrode film layer, and a second flexible substrate layer.

5. The smart glove according to any one of claims 1 to 3, characterized in that: The rigid gasket is a polymethyl methacrylate (PMMA) gasket.

6. The smart glove according to claim 1, characterized in that: The pressure sensor is adhered to the surface of the glove by silicone glue.

7. The smart glove according to claim 1, characterized in that: The rigid gasket is fixed on the surface of the flexible pressure sensor by gluing.

8. The smart glove according to claim 1, characterized in that: There are 13 pressure sensors, which are arranged at the following locations: the first pulp of the index finger, middle finger, ring finger and little finger; the third pulp of the index finger, middle finger, ring finger and little finger; the metacarpophalangeal joints corresponding to the index finger, middle finger, ring finger and little finger; and the first pulp of the thumb.

9. The smart glove according to claim 1, characterized in that: The diameter of the steel conductor is 0.45 mm; the thickness of the coated silicone film is 0.5 mm.

10. The smart glove according to claim 1 or 8, characterized in that: The silicone film is prepared by mixing polydimethylsiloxane (PDMS) and a curing agent in a mass ratio of 9:1, vacuum degassing the mixture until no bubbles appear, pouring the mixture into an aluminum alloy mold, heating and curing, and peeling off the mold after cooling to obtain the silicone film.

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