CN107328497B - A signal detection sensing structure, its manufacturing method, and signal detection method - Google Patents

Abstract

The invention discloses a signal detection sensing structure, a manufacturing method thereof, and a signal detection method, wherein the signal detection sensing structure includes: a first piezoelectric electret layer, a second piezoelectric electret layer, and a An adhesive layer between the first piezoelectric electret layer and the second piezoelectric electret layer; the side of the first piezoelectric electret layer away from the second piezoelectric electret layer The surface includes a plurality of raised structures; the surface of the second piezoelectric electret layer adjacent to the first piezoelectric electret layer is a smooth surface; the first piezoelectric electret layer is used to detect The contact signal and/or the sliding signal of the touching object, the second piezoelectric electret layer is used to detect the contact signal of the touching object. The stacked structure of the first piezoelectric electret layer and the second piezoelectric electret layer realizes simultaneous detection of contact signals and sliding signals by a single sensing unit, and the signal detection sensing structure provided by the embodiment of the present invention is simple in structure , high sensitivity, basically no pyroelectric effect, basically not affected by temperature changes within the working temperature range, and can realize high-precision detection of contact signals and sliding signals.

Description

A signal detection sensing structure, its manufacturing method, and signal detection method

technical field

Embodiments of the present invention relate to signal detection technology, in particular to a signal detection sensing structure, a manufacturing method thereof, and a signal detection method.

Background technique

The senses related to hand function mainly include contact, pressure, position, sliding, temperature, etc. The survey shows that contact and grasping are more important. In the research, we also found that "contact" and "sliding" are the two most important types of sensory information of the prosthetic hand, which exist in most prosthetic hand movements ("waving" etc. except), is the key to achieve a safe and reliable grip. The touch-slip signal can be obtained by analyzing the interaction force between the prosthetic hand and the object. Generally speaking, the "touch" signal is mainly static force, while the "slide" signal is mainly dynamic force.

The most common static force sensors are capacitive and resistive sensors. Capacitive sensors measure pressure by measuring capacitance changes between parallel plates, but their circuits are complex and subject to electromagnetic interference. Resistive sensors, including piezoresistive and contact resistive, measure pressure by measuring changes in material resistivity, but their sensitivity and signal stability are limited. In addition, methods such as strain gauges can also be used to detect sensory signals of prosthetic hands, but there are also shortcomings such as complex structures and low sensitivity.

Common dynamic force sensors include piezoelectric and triboelectric sensors. The preparation process of these two types of sensors is relatively high, and the signal of the piezoelectric material is affected by the temperature. When grasping a hotter or colder object, the temperature change interferes with the detection of the sensory signal. In addition, an array composed of multiple resistive sensors can also be used to detect sliding signals. There are also photoelectric, acoustic-electric, and electromagnetic sensors that obtain signals indirectly, but they all have complex structures, difficult fabrication, and Low reliability, difficult to guarantee accuracy and other shortcomings.

At present, piezoelectric films such as polyvinylidene can be used to detect contact signals and sliding signals at the same time, but it is difficult to separate the signals, making the detection accuracy of the two signals low.

Contents of the invention

The invention provides a signal detection sensing structure, a manufacturing method thereof, and a signal detection method, so as to realize simultaneous detection of a contact signal and a sliding signal by a single sensing unit, and improve the detection accuracy of the contact signal and the sliding signal.

In the first aspect, an embodiment of the present invention provides a signal detection sensing structure, including: a first piezoelectric electret layer, a second piezoelectric electret layer, and The adhesive layer between the second piezoelectric electret layers; the surface of the first piezoelectric electret layer away from the second piezoelectric electret layer includes a plurality of convex structures; The surface of the second piezoelectric electret layer adjacent to the first piezoelectric electret layer is a smooth surface; the first piezoelectric electret layer is used to detect the contact signal and/or sliding of the touching object signal, the second piezoelectric electret layer is used to detect the contact signal of the touching object.

Further, the first piezoelectric electret layer and the second piezoelectric electret layer have a microporous structure, and the cross-sectional shape of the microporous structure includes at least one of a circle, an ellipse and a polygon. kind.

Further, the material of the first piezoelectric electret layer includes at least one of fluorinated ethylene propylene copolymer and polytetrafluoroethylene.

Further, the material of the second piezoelectric electret layer includes at least one of polypropylene, polyethylene terephthalate and polyethylene naphthalate.

Further, the first piezoelectric electret layer is laminated and adhered to the second piezoelectric electret layer through the adhesive layer by pasting, hot pressing or melting process.

Further, the signal detection sensing structure further includes: a signal processing module; a first electrode is provided on the side of the first piezoelectric electret layer away from the second piezoelectric electret layer, and the first piezoelectric electret layer A piezoelectric electret layer is provided with a second electrode on a side close to the second piezoelectric electret layer; a side of the second piezoelectric electret layer close to the first piezoelectric electret layer A third electrode is provided on one side of the piezoelectric electret layer, the second electrode and the third electrode are insulated from each other, and a fourth piezoelectric electret layer is provided on the side away from the first piezoelectric electret layer. Electrodes; the signal processing module is electrically connected to the first electrode, the second electrode, the third electrode, and the fourth electrode, respectively, and is used to calculate a contact signal and/or a sliding signal of a touching object.

In the second aspect, the embodiment of the present invention also provides a method for manufacturing the signal detection sensing structure according to the first aspect, including: providing a second piezoelectric electret layer; One side of the polar body layer is attached with an adhesive layer; a first piezoelectric electret layer is provided, and the first piezoelectric electret layer is bonded to the second piezoelectric electret layer through the adhesive layer. On the electret layer; wherein, the surface of the first piezoelectric electret layer away from the second piezoelectric electret layer includes a plurality of convex structures; the second piezoelectric electret layer The side surface adjacent to the first piezoelectric electret layer is a smooth surface; the first piezoelectric electret layer is used to detect the contact signal and/or sliding signal of the touch object, and the second piezoelectric electret layer The polar body layer is used to detect contact signals of touching objects.

Further, the first piezoelectric electret layer and/or the second piezoelectric electret layer are formed by an expansion method, a template method or an etching method.

Further, the first piezoelectric electret layer is laminated and adhered to the second piezoelectric electret layer through the adhesive layer by pasting, hot pressing or melting process.

In the third aspect, the embodiment of the present invention also provides a signal detection method of the signal detection sensing structure according to the first aspect, including: acquiring the first signal detected by the first piezoelectric electret layer and the second piezoelectric electret layer The second signal detected by the electroelectret layer; determining the contact signal and/or sliding signal of the touching object according to the first signal, and determining the contact signal of the touching object according to the second signal.

Further, the detecting the contact signal and/or sliding signal of the touching object according to the first signal, and detecting the contact signal of the touching object according to the second signal; include: if the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, then it is determined that the first signal is a contact signal of a touching object; if the number of signal peaks of the first signal is greater than 1, and the number of signal peaks The amplitudes are all less than the first preset value, and when the signal variance of the first signal is less than the second threshold, it is determined that the first signal is a sliding signal of the touching object; if the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, then it is determined that the second signal is a contact signal of a touching object.

Further, the detecting the contact signal and/or the sliding signal of the touching object according to the first signal, and detecting the contact signal of the touching object according to the second signal; include: if the number of signal peaks of the first signal is greater than 1 and the amplitude of one of the signal peaks is greater than the first preset value, the difference between the absolute value of the first signal and the absolute value of the second signal is used as a third signal, and the third signal is determined is a sliding signal of the touching object; determining the second signal as a contact signal of the touching object.

Further, if the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, and the signal peak value of the first signal is greater than 0, it is determined that the touching object is in a gradual contact state ; If the number of signal peaks of the first signal changes from 1 to 0, it is determined that the touch object is from a gradual contact state to a clenched state; if the number of signal peaks of the first signal is equal to 1 and the signal If the amplitude of the peak is greater than a first preset value, and the signal peak value of the first signal is less than 0, it is determined that the touching object is in a disengaged state.

Further, if the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than the first preset value, and the signal peak value of the second signal is greater than 0, it is determined that the touching object is in a gradual contact state ; If the number of signal peaks of the second signal changes from 1 to 0, it is determined that the touch object is from a gradual contact state to a clenched state; if the number of signal peaks of the second signal is equal to 1 and the signal If the amplitude of the peak is greater than the first preset value, and the signal peak value of the second signal is less than 0, then it is determined that the touching object is in a disengaged state.

The signal detection sensing structure provided by the present invention includes a first piezoelectric electret layer, a second piezoelectric electret layer and a layer located between the first piezoelectric electret layer and the second piezoelectric electret layer The adhesive layer between the electret layers, the surface of the first piezoelectric electret layer away from the second piezoelectric electret layer includes a plurality of convex structures to detect contact signals and/or sliding of touching objects signal, the surface of the second piezoelectric electret layer adjacent to the first piezoelectric electret layer is a smooth surface to detect the contact signal of the touching object, the first piezoelectric electret layer and the second piezoelectric electret layer The laminated structure of the body layer realizes the simultaneous detection of the contact signal and the sliding signal by a single sensing unit. The signal detection and sensing structure provided by the embodiment of the present invention is simple in structure, high in sensitivity, basically free of pyroelectric effect, and can operate within the working temperature range. The inside is basically not affected by temperature changes, and can realize high-precision detection of contact signals and sliding signals.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic diagram of a signal detection sensor structure provided by an embodiment of the present invention.

Fig. 2 is a schematic diagram of the connection between the processing module of the signal detection sensing structure provided by the embodiment of the present invention and the first piezoelectric electret layer and the second piezoelectric electret layer.

Fig. 3 is a flowchart of a method for manufacturing a signal detection sensing structure provided by an embodiment of the present invention.

Fig. 4 is a flowchart of a signal detection method of a signal detection sensing structure provided by an embodiment of the present invention.

Fig. 5 is a schematic diagram of the output of the contact signal detected by the signal detection sensing structure provided by the embodiment of the present invention.

Fig. 6 is a schematic diagram of the sliding signal output detected by the signal detection sensing structure provided by the embodiment of the present invention.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention. In addition, it should be noted that, for the convenience of description, only some structures related to the present invention are shown in the drawings but not all structures.

Fig. 1 is a schematic diagram of a signal detection sensing structure provided by an embodiment of the present invention. The signal detection sensing structure shown in Fig. 1 includes: a first piezoelectric electret layer 1, a second piezoelectric electret layer 2 and an adhesive layer 5 between the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2; the adhesive layer 5 connects the first piezoelectric electret layer 1 and the second piezoelectric electret layer The polar layer 2 is laminated and bonded. The surface of the first piezoelectric electret layer 1 away from the second piezoelectric electret layer 2 includes a plurality of raised structures 3; the second piezoelectric electret layer 2 is adjacent to the first piezoelectric electret layer 1 One side of the surface is a smooth surface; the first piezoelectric electret layer 1 is used to detect the contact signal and/or sliding signal of the touching object, and the second piezoelectric electret layer 2 is used to detect the contact signal of the touching object.

The signal detection sensing structure provided by the embodiment of the present invention can be worn on the artificial skin of a prosthesis or a robotic hand, for example, and the operation of the prosthesis on a touch object includes, for example, sliding operation and pressing operation. The pressing operation is mainly a static force, and the pressing operation can be obtained by detecting the pressure on the contact surface of the prosthesis and the touching object. The sliding operation is mainly a dynamic force. For the sliding operation, the prosthetic skin and the touching object seem smooth, but there are a large number of tiny bumps distributed in the microstructure. When the two slide relative to each other, micro vibrations will be generated. The vibration of the convex peak is obtained. The signal detection sensing structure provided by the present invention uses a piezoelectric electret, and the microporous structure with charges (dipoles) stored inside the piezoelectric electret will deform under the action of an external force (static force, dynamic force). Thereby changing the electric dipole moment, compensating for the change of charge, and showing a corresponding charge or voltage signal to the outside, so that the sliding operation and pressing operation between the prosthesis and the touching object can be detected. Referring to FIG. 1 , the signal detection sensing structure provided by the embodiment of the present invention includes a plurality of protrusion structures 3 on the surface of the first piezoelectric electret layer 1 away from the second piezoelectric electret layer 2 . When a relative sliding occurs between the surface of the piezoelectric electret layer 1 away from the second piezoelectric electret layer 2 and the touching object, the first piezoelectric electret layer 1 can detect the micro-vibration caused by the sliding, so it can Detect swipe signal. When the prosthesis presses the touch object, the first piezoelectric electret layer 1 in the signal detection sensing structure worn on the prosthesis transmits the pressure to the second piezoelectric electret layer 2, and the first piezoelectric electret layer 1 And the second piezoelectric electret layer 2 can detect the contact signal. When the prosthesis wearing the signal detection sensing structure has both sliding touch and force pressing operation on the touching object, the first piezoelectric electret layer 1 can detect the sliding signal and the contact signal, and transmit the pressure to the second piezoelectric electret layer 1. The second piezoelectric electret layer 2 enables the second piezoelectric electret layer 2 to detect a contact signal.

The signal detection sensing structure provided by the embodiment of the present invention includes a laminated structure of the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2. The laminated structure not only realizes a single sensing unit for contact signal Simultaneous detection of sliding signals, and compared to traditional capacitive, resistive, piezoelectric and friction sensors, the quality of the first piezoelectric electret layer and the second piezoelectric electret layer in the embodiments of the present invention It is light, thin, soft and bendable, and has a certain degree of stretchability, so it can be easily embedded into the surface of the artificial skin of the prosthetic hand. In addition, since the first piezoelectric electret layer and the second piezoelectric electret layer have high sensitivity, good linearity, basically no pyroelectric effect, and are basically not affected by temperature changes in the working temperature range, it is possible to realize contact High-precision detection of signal and sliding signal, and the signal detection sensor provided by the embodiment of the present invention has a simple structure, so the preparation process is simple, the cost is low, and the application potential is very large.

Specifically, the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2 have a microporous structure 4. It should be noted that the second piezoelectric electret layer shown in FIG. 1 The cross-sectional shape of the microporous structure 4 of 2 is exemplary elliptical, and the cross-sectional shape of the microporous structure 4 in the first piezoelectric electret layer 1 shown in FIG. 1 is exemplary set to a half-elliptical shape , which is just an example and not limiting. In other embodiments, the cross-sectional shape of the microporous structure 4 in the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2 includes a circular shape At least one of , ellipse and polygon. It should be noted that the microporous structures 4 of the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2 may be the same or different, and may be determined according to actual preparation conditions, raw materials and other factors.

Optionally, the material of the first piezoelectric electret layer 1 includes at least one of fluorinated ethylene propylene copolymer and polytetrafluoroethylene. Optionally, the material of the second piezoelectric electret layer 2 includes at least one of polypropylene, polyethylene terephthalate and polyethylene naphthalate.

Optionally, the first piezoelectric electret layer 1 is laminated and bonded to the second piezoelectric electret layer 2 through the adhesive layer 5 by pasting, hot pressing or melting process, which can not only ensure that when the object is pressed, The pressure can be transmitted from the first piezoelectric electret layer 1 to the second piezoelectric electret layer 2 without distortion, and also without damaging the overall flexibility of the signal detection sensing structure.

Specifically, the signal detection sensing structure also includes: a signal processing module 6, as shown in FIG. and the connection schematic diagram of the second piezoelectric electret layer 2, it should be noted that, in order to clearly describe the electrical connection between the processing module 6 and the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2, FIG. Connection relationship, the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2 are shown separately, but the first piezoelectric electret 1 and the second piezoelectric electret 2 are actually stacked and bonded together. Between the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2 is an insulating adhesive layer 5, which not only plays the role of bonding, but also plays the role of insulating the second electrode 8 and the third electrode 9. effect. The adhesive layer 5 is made of a flexible film material, which does not affect the overall flexibility of the sensing structure, and can transmit pressure signals from the first piezoelectric electret layer 1 to the second piezoelectric electret layer 2 well. The side of the first piezoelectric electret layer 1 away from the second piezoelectric electret layer 2 is provided with a first electrode 7, and the first piezoelectric electret layer 1 is close to a side of the second piezoelectric electret layer 2. A second electrode 8 is provided on the side; a third electrode 9 is provided on the side of the second piezoelectric electret layer 2 close to the first piezoelectric electret layer 1, and the second electrode 8 and the third electrode 9 are insulated from each other. A fourth electrode 10 is provided on the side of the second piezoelectric electret layer 2 away from the first piezoelectric electret layer 1 . The first electrode 7, the second electrode 8, the third electrode 9 and the fourth electrode 10 can be, for example, very thin metal electrode layers, including but not limited to conductive materials such as aluminum, silver, gold, etc., and the preparation method of the metal electrode layer includes but It is not limited to methods such as evaporation deposition, magnetron sputtering, and the like. The signal processing module 6 is electrically connected to the first electrode 7 , the second electrode 8 , the third electrode 9 , and the fourth electrode 10 , and is used to calculate the contact signal and/or the sliding signal of the touching object.

Optionally, the first piezoelectric electret layer 1 and the second piezoelectric electret layer 2 can share a signal processing module, or can give the first piezoelectric electret 1 and the second piezoelectric electret 2 Set up a signal processing module respectively, and take the first case as an example here.

Specifically, the signal processing module is provided with a first signal terminal, a first ground terminal, a second signal terminal and a second ground terminal, and the first signal terminal is electrically connected to the first electrode 7 for obtaining a contact signal of a touching object and/or Or sliding signal, the first ground terminal is electrically connected with the second electrode 8, used to realize electromagnetic shielding, and reduces other external signal interference; the second signal terminal is electrically connected with the third electrode 9, used to obtain the contact signal of the touching object, the second The two ground terminals are electrically connected to the fourth electrode 10 for realizing electromagnetic shielding and reducing interference from other external signals. It should be noted that the connection between the first signal terminal and the first ground terminal and the first electrode 7 and the second electrode 8 and the connection between the second signal terminal and the second ground terminal and the third electrode 9 and the fourth electrode 10 are selected as follows: It is not specifically limited, and it may also be that the first signal terminal is electrically connected to the second electrode 8, the first ground terminal is electrically connected to the first electrode 7, the second signal terminal is electrically connected to the fourth electrode 10, and the second ground terminal is electrically connected to the fourth electrode 10. The third electrode 9 is electrically connected.

The embodiment of the present invention also provides a method for manufacturing the signal detection and sensing structure as described in the above embodiments. FIG. 3 is a flow chart of the method for manufacturing the signal detection and sensing structure provided by the embodiment of the present invention. As shown in FIG. 3 , it includes :

S101. Provide a second piezoelectric electret layer.

S102. Attach an adhesive layer on one side of the second piezoelectric electret layer.

S103, providing a first piezoelectric electret layer, and laminating and bonding the first piezoelectric electret layer on the second piezoelectric electret layer through the adhesive layer.

Specifically, the surface of the first piezoelectric electret layer away from the second piezoelectric electret layer includes a plurality of convex structures; the second piezoelectric electret layer is adjacent to one side of the first piezoelectric electret layer. The side surface is a smooth surface; the first piezoelectric electret layer is used to detect the contact signal and/or sliding signal of the touching object, and the second piezoelectric electret layer is used to detect the contact signal of the touching object.

Optionally, the first piezoelectric electret layer and/or the second piezoelectric electret layer are formed by an expansion method, a template method or an etching method.

Optionally, the first piezoelectric electret layer is laminated and bonded to the second piezoelectric electret layer through an adhesive layer by using paste, hot pressing or melting process, which can not only ensure the contact signal from the first piezoelectric electret layer The polar body layer is transmitted to the second piezoelectric electret layer without distortion, and also without damaging the overall flexibility of the signal detection sensing structure.

The embodiment of the present invention also provides the signal detection method of the signal detection sensing structure as described in the above embodiments, and FIG. 4 is a flow chart of the signal detection method of the signal detection sensing structure provided by the embodiment of the present invention, as shown in FIG. 4 ,include:

S201. Acquire a first signal detected by the first piezoelectric electret layer and a second signal detected by the second piezoelectric electret layer.

S201. Determine a contact signal and/or a sliding signal of a touching object according to a first signal, and determine a contact signal of a touching object according to a second signal.

Specifically, the signal detection method of the signal detection sensing structure provided by the embodiment of the present invention can, for example, perform signal detection on the signal detection sensing structure worn on the prosthesis, and the operation of the prosthesis on the touch object includes sliding operation and pressing operation. The pressing operation is mainly a static force, and the pressing operation can be obtained by detecting the pressure on the contact surface between the prosthetic hand and the touching object. The sliding operation is mainly a dynamic force. For the sliding operation, the prosthetic skin and the touching object seem smooth, but there are a large number of tiny bumps distributed in the microstructure. When the two slide relative to each other, micro vibrations will be generated. The vibration of the convex peak is obtained. The signal detection method of the signal detection sensing structure provided by the embodiments of the present invention is based on the characteristics of the piezoelectric electret, and the microporous structure with charges (dipoles) stored inside the piezoelectric electret is subjected to external forces (static force, dynamic force) ) will produce deformation, thereby changing the electric dipole moment, compensating for the change of charge, and showing a corresponding charge or voltage signal to the outside, so it can detect the sliding operation and pressing operation between the prosthesis and the touching object. Referring to FIG. 1 , the signal detection method of the signal detection sensing structure provided by the embodiment of the present invention includes a plurality of convex structures 3 on the surface of the first piezoelectric electret layer 1 away from the second piezoelectric electret layer 2 , When a relative sliding occurs between the surface of the first piezoelectric electret layer 1 away from the second piezoelectric electret layer 2 and the touching object, the first piezoelectric electret layer 1 can detect the micro vibration caused by sliding , so the sliding signal can be detected, and the detected sliding signal is used as the first signal. When the prosthesis presses the touch object, the first piezoelectric electret layer 1 in the signal detection sensing structure worn on the prosthesis transmits the pressure to the second The two piezoelectret layers 2 , the first piezoelectret layer 1 and the second piezoelectret layer 2 can all detect contact signals, and use the detected contact signals as the second signal. When the prosthesis wearing the signal detection sensing structure has both sliding touch and force pressing operation on the touching object, the first piezoelectric electret layer 1 can detect the sliding signal and the contact signal, and transmit the pressure to the second piezoelectric electret layer 1. The second piezoelectret layer 2 enables the second piezoelectret layer 2 to detect the contact signal, the detected sliding signal is used as the first signal, and the detected contact signal is used as the second signal.

The signal detection method of the signal detection sensor structure provided by the embodiment of the present invention first obtains the first signal detected by the first piezoelectric electret and the second signal detected by the second piezoelectric electret layer, and then determines the The contact signal and/or the sliding signal of the touching object, the contact signal of the touching object is determined according to the second signal, and the simultaneous detection of the contact secondary signal and the sliding signal is realized. In addition, due to the first piezoelectric electret layer and the second piezoelectric The electret layer has high sensitivity, good linearity, basically no pyroelectric effect, and is basically not affected by temperature changes within the working temperature range, so it can realize high-precision detection of contact signals and sliding signals.

Fig. 5 is a schematic diagram of the contact signal output of the signal detection sensing structure detection provided by the embodiment of the present invention. As shown in Fig. 5, when touching an object, the signal output of the contact signal is an isolated signal peak, and the amplitude of the signal peak bigger. Fig. 6 is a schematic diagram of the sliding signal output of the signal detection sensor structure detection provided by the embodiment of the present invention. As shown in Fig. 6, the signal output of the sliding signal is a series of irregular micro-vibrations, there are multiple signal peaks, and the signal peaks magnitudes are small. Therefore, the first threshold and the second threshold can be set, and the touch signal and the sliding signal can be distinguished according to the number of signal peaks and the comparison of the amplitude of the signal peak with the first threshold and the variance of the signal with the second threshold.

Optionally, detecting the contact signal and/or sliding signal of the touching object according to the first signal, and detecting the contact signal of the touching object according to the second signal; including:

If the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, then determining that the first signal is a contact signal of a touching object;

If the number of signal peaks of the first signal is greater than 1, and the amplitudes of the signal peaks are all less than the first preset value, and when the signal variance of the first signal is less than the second threshold, it is determined that the first signal is a sliding signal of the touching object ;

If the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, then it is determined that the second signal is a contact signal of a touching object.

Since the first piezoelectric electret layer can detect both the contact signal and the sliding signal, the embodiment of the present invention can also realize the separation of the detected contact signal and sliding signal through the above method. If the number of signal peaks of the first signal detected by the first piezoelectric electret is equal to 1, and the amplitude of the signal peak is greater than the first preset value, it means that there is only one isolated signal peak in the first signal, and the signal peak The amplitude of is relatively large, that is, only the contact signal exists in the first signal, and at this time, the first signal is determined as the contact signal of the touching object. If the number of signal peaks of the first signal is greater than 1, and the amplitudes of the signal peaks are all less than the first preset value, it means that there is no contact signal in the first signal, and if the signal variance of the first signal is less than the second threshold, then it means The first signal is a series of irregular tiny vibrations, there are multiple signal peaks, and the amplitudes of the signal peaks are all small, that is, there is only a sliding signal in the first signal, and at this time, the first signal is determined to be the sliding of the touching object Signal. Since the second piezoelectric electret layer can only detect contact signals, there is no need for signal separation, only when the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peaks is greater than the first preset value, then The second signal is determined to be a contact signal of the touching object.

Optionally, detecting the contact signal and/or sliding signal of the touching object according to the first signal, and detecting the contact signal of the touching object according to the second signal; including:

If the number of signal peaks of the first signal is greater than 1 and the amplitude of one of the signal peaks is greater than the first preset value, the difference between the absolute value of the first signal and the absolute value of the second signal is used as the third signal, and the third The signal is determined to be a sliding signal of the touching object;

The second signal is determined as a contact signal of the touching object.

If the number of signal peaks of the first signal detected by the first piezoelectric electret is greater than 1, and the amplitude of one of the signal peaks is greater than the first preset value, it means that there are both contact signals and Swipe signal. Since the second signal detected by the second piezoelectric electret layer is a contact signal, and the contact signal detected by the second piezoelectric electret layer is transmitted by the first piezoelectric electret layer, the two detected The touch signals are equal in magnitude. Specifically, the touch signal in the first signal can be removed by making a difference between the absolute value of the first signal and the absolute value of the second signal. The difference is used as the third signal, and the third signal is the touch object. the sliding signal.

Optionally, the signal detection method of the signal detection sensing structure provided in the embodiment of the present invention further includes:

If the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, and the signal peak value of the first signal is greater than 0, then it is determined that the touching object is in a gradual contact state;

If the number of signal peaks of the first signal changes from 1 to 0, then it is determined that the touching object is changed from a gradual contact state to a clenched state;

If the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peaks is greater than a first preset value, and the signal peak value of the first signal is less than 0, it is determined that the touching object is in a disengaged state.

If the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than the first preset value, it means that there is only one isolated signal peak in the first signal, and the amplitude of the signal peak is relatively large, that is, the first There is only a contact signal in the first signal, and because the signal peak value of the first signal is greater than 0, it means that the touching object is in the process of gradually contacting; if the number of signal peaks of the first signal changes from 1 to 0, it means that the first signal has changed from The ever-changing signal output becomes no signal output, that is, the touch object changes from a gradually contacted state to a clenched state; if the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than the first preset value, it means that the first There is only one isolated signal peak in the first signal, and the amplitude of the signal peak is relatively large, that is, there is only a contact signal in the first signal, and because the signal peak value of the first signal is less than 0, it means that the touching object is out of contact.

Optionally, the signal detection method of the signal detection sensing structure provided in the embodiment of the present invention further includes:

If the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than the first preset value, and the signal peak value of the second signal is greater than 0, then it is determined that the touching object is in a gradual contact state;

If the number of signal peaks of the second signal changes from 1 to 0, then it is determined that the touching object is changed from a gradual contact state to a clenched state;

If the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peaks is greater than the first preset value, and the signal peak value of the second signal is less than 0, it is determined that the touching object is in a disengaged state.

If the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than the first preset value, it means that there is only one isolated signal peak in the second signal, and the amplitude of the signal peak is relatively large, that is, the first The second signal is a contact signal, and because the peak value of the second signal is greater than 0, it means that the touching object is in the process of gradually contacting; if the number of signal peaks of the second signal changes from 1 to 0, it means that the second signal changes from The ever-changing signal output becomes no signal output, that is, the touching object changes from a gradual contact state to a clenched state; if the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than the first preset value, it means that the first There is only one isolated signal peak in the second signal, and the amplitude of the signal peak is relatively large, that is, the second signal is a contact signal, and because the signal peak value of the second signal is less than 0, it indicates that the touching object is out of contact.

The signal detection method of the signal detection sensor structure provided by the embodiment of the present invention first obtains the first signal detected by the first piezoelectric electret and the second signal detected by the second piezoelectric electret layer, and then determines the The contact signal and/or the sliding signal of the touching object, the contact signal of the touching object is determined according to the second signal, and the simultaneous detection of the contact secondary signal and the sliding signal is realized. In addition, due to the first piezoelectric electret layer and the second piezoelectric The electret layer has high sensitivity, good linearity, basically no pyroelectric effect, and is basically not affected by temperature changes within the working temperature range, so it can realize high-precision detection of contact signals and sliding signals. The signal detection method provided by the present invention provides a method for separating the contact signal and the sliding signal in the first signal according to the characteristics of the contact signal and the sliding signal, and can determine whether the signal detection sensing structure described in the present invention is worn The grasping state of the prosthetic hand, such as judging whether the touching object is in a gradual contact state, a clenched state, or a disengagement state, realizes the practical application of the new sensing unit.

Note that the above are only preferred embodiments of the present invention and applied technical principles. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, rearrangements and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and can also include more other equivalent embodiments without departing from the concept of the present invention, and the present invention The scope is determined by the scope of the appended claims.

Claims (10)

1. A signal detection sensing structure, characterized in that, comprising: a first piezoelectric electret layer, a second piezoelectric electret layer, and an adhesive layer between the first piezoelectric electret layer and the second piezoelectric electret layer; The surface of the first piezoelectric electret layer away from the second piezoelectric electret layer includes a plurality of convex structures; the second piezoelectric electret layer is adjacent to the first piezoelectric electret layer One side surface of the polar body layer is a smooth surface; The first piezoelectric electret layer is used to detect a contact signal and a sliding signal of a touching object, and the second piezoelectric electret layer is used to detect a contact signal of a touching object; Laminating the first piezoelectric electret layer on the second piezoelectric electret layer through the adhesive layer by pasting, hot pressing or melting; The material of the first piezoelectric electret layer includes at least one of fluorinated ethylene propylene copolymer and polytetrafluoroethylene. 2. The signal detection sensing structure according to claim 1, characterized in that, the first piezoelectric electret layer and the second piezoelectric electret layer have a microporous structure, and the micropores The cross-sectional shape of the structure includes at least one of circle, ellipse and polygon. 3. The signal detection sensing structure according to claim 1, wherein the material of the second piezoelectric electret layer comprises polypropylene, polyethylene terephthalate and polyethylene naphthalate at least one of glycol esters. 4. The signal detection sensing structure according to claim 1, further comprising: a signal processing module; A first electrode is provided on the side of the first piezoelectric electret layer away from the second piezoelectric electret layer, and the first piezoelectric electret layer is close to the second piezoelectric electret One side of the layer is provided with a second electrode; the side of the second piezoelectric electret layer close to the first piezoelectric electret layer is provided with a third electrode, and the second electrode and the third The electrodes are insulated from each other, and a fourth electrode is provided on the side of the second piezoelectric electret layer away from the first piezoelectric electret layer; The signal processing module is electrically connected to the first electrode, the second electrode, the third electrode, and the fourth electrode, respectively, and is used for calculating a contact signal and/or a sliding signal of a touching object. 5. A method for making a signal detection sensing structure according to any one of claims 1-4, characterized in that, comprising: providing a second piezoelectric electret layer; attaching an adhesive layer on one side of the second piezoelectric electret layer; providing a first piezoelectric electret layer, and laminating and bonding the first piezoelectric electret layer on the second piezoelectric electret layer through the adhesive layer; Wherein, the surface of the first piezoelectric electret layer away from the second piezoelectric electret layer includes a plurality of convex structures; the second piezoelectric electret layer is adjacent to the first piezoelectric electret layer. One side surface of the electroelectret layer is a smooth surface; the first piezoelectric electret layer is used to detect the contact signal and/or sliding signal of the touching object, and the second piezoelectric electret layer is used to detect contact signal of the touching object; The first piezoelectric electret layer is laminated and bonded on the second piezoelectric electret layer through the adhesive layer by pasting, hot pressing or melting process. 6 . The method according to claim 5 , wherein the first piezoelectric electret layer and/or the second piezoelectric electret layer are formed by an expansion method, a template method or an etching method. 7. A signal detection method of the signal detection sensing structure according to any one of claims 1-4, characterized in that, comprising: acquiring a first signal detected by the first piezoelectric electret layer and a second signal detected by the second piezoelectric electret layer; determining a contact signal and/or a sliding signal of the touching object according to the first signal, and determining a contact signal of the touching object according to the second signal; If the number of signal peaks of the first signal is greater than 1 and the amplitude of one of the signal peaks is greater than a first preset value, the difference between the absolute value of the first signal and the absolute value of the second signal is used as a third signal, determining the third signal as a sliding signal of the touching object; The second signal is determined as a contact signal of a touching object. 8. The method according to claim 7, wherein the determining the contact signal and/or sliding signal of the touching object according to the first signal, and determining the contact signal of the touching object according to the second signal; comprising: If the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, then determining that the first signal is a contact signal of a touching object; If the number of signal peaks of the first signal is greater than 1, and the amplitudes of the signal peaks are all less than a first preset value, and when the signal variance of the first signal is less than a second threshold, determine the first A signal is a sliding signal of the touching object; If the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, then it is determined that the second signal is a contact signal of a touching object. 9. The method according to claim 7, further comprising: If the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, and the signal peak value of the first signal is greater than 0, it is determined that the touching object is in a gradual contact state; If the number of signal peaks of the first signal changes from 1 to 0, it is determined that the touching object is from a gradual contact state to a clenched state; If the number of signal peaks of the first signal is equal to 1 and the amplitude of the signal peaks is greater than a first preset value, and the signal peak value of the first signal is less than 0, it is determined that the touching object is in a disengaged state. 10. The method of claim 7, further comprising: If the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peak is greater than a first preset value, and the signal peak value of the second signal is greater than 0, then it is determined that the touching object is in a gradual contact state; If the number of signal peaks of the second signal changes from 1 to 0, it is determined that the touching object is changed from a gradual contact state to a clenched state; If the number of signal peaks of the second signal is equal to 1 and the amplitude of the signal peaks is greater than a first preset value, and the signal peak value of the second signal is less than 0, it is determined that the touching object is in a disengaged state.

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