CN111289157B - Circuit and method for measuring pressure distribution through piezoresistive sensing array - Google Patents
Circuit and method for measuring pressure distribution through piezoresistive sensing array Download PDFInfo
- Publication number
- CN111289157B CN111289157B CN202010379722.8A CN202010379722A CN111289157B CN 111289157 B CN111289157 B CN 111289157B CN 202010379722 A CN202010379722 A CN 202010379722A CN 111289157 B CN111289157 B CN 111289157B
- Authority
- CN
- China
- Prior art keywords
- port
- piezoresistive
- analog
- sampling
- controller
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/18—Measuring force or stress, in general using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
The invention discloses a circuit for measuring pressure distribution by a piezoresistive sensing array, which belongs to the technical field of pressure measurement and comprises: a piezoresistive sensing array consisting ofM×NArray distributed piezoresistive sensorR ij Composition is carried out; a reverse analog gating module; a forward analog gating module; a controller; an analog-to-digital converter; piezoresistive sensorR ij One end of and a scanning portA i Connected at the other end to a sampling portB j Bonded piezoresistive sensorR ij And a sampling portB j All provided with a controllable tri-state gate therebetweenC j (ii) a Piezoresistive sensorR ij Is connected with a nominal resistorR j (ii) a The controller can enable the scanning port of the reverse analog gating module and the sampling port of the forward analog gating module to be communicated with the piezoresistive sensors in the piezoresistive sensing array, can simply and quickly calculate the pressure of the piezoresistive sensors, forms pressure distribution mapping based on the positions of the piezoresistive sensors, and is high in scanning and sampling speed, small in measurement error, simple and easy to realize in structure, low in cost and low in power consumption, and suitable for industrial application and popularization.
Description
Technical Field
The invention relates to the technical field of pressure measurement, in particular to a circuit and a method for measuring pressure distribution through a piezoresistive sensing array.
Background
With the development of big data and high-speed operation technology, artificial intelligence is applied and developed more deeply and widely in various fields, a set of complete artificial intelligence system or application comprises data acquisition operation, cognitive understanding and action feedback, and the width, precision and speed of data acquisition of system equipment determine the intelligent degree of the system to a great extent. For intelligent equipment, data acquisition basically depends on various sensors, such as an optical sensor, a pressure sensor, a force sensor, a gas sensor and the like, and the various sensors cooperate better, so that the data acquisition breadth can be improved, and the information sensing capability of the intelligent equipment is improved.
The piezoresistive sensor array can measure the size and the position of contact force between objects, track the change condition of force distribution, effectively assist intelligent equipment to automatically sense and acquire force information, and improve the intelligent degree of the equipment. Aiming at the structural characteristics of the piezoresistive sensor array, the invention provides a measuring circuit which is simple, easy to realize, high in speed and small in error and the working time sequence steps of the circuit. According to the invention, through a strict time sequence, key components in the control circuit quickly enter a stable state, and the voltage scanning and sampling are completed at the same time, so that the resistance value of each sensing point is calculated, and further the pressure distribution and change conditions of the whole pressure sensing array coverage area are obtained.
Disclosure of Invention
For the problems in the prior art, the circuit and the method for measuring the pressure distribution through the piezoresistive sensing array can measure the pressure distribution of the piezoresistive sensing array, and have the advantages of high scanning and sampling speed, small measurement error, simple structure, easiness in realization, low cost and low power consumption, and are suitable for industrial application and popularization.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
in one aspect, the present invention provides a circuit for measuring pressure distribution by a piezoresistive sensing array, comprising:
a piezoresistive sensing array consisting ofM×NArray distributed piezoresistive sensorR ij The composition of the components, wherein,Min the case of the number of rows,Nin order to count the number of columns,i=1、2、…、M，j=1、2、…、N；
the reverse analog gating module is provided with a reverse analog gating control port, a voltage input port andMa scanning portA i ，i=1、2、…、M；
The forward analog gating module is provided with a forward analog gating control port, an output port andNa sampling portB j ，j=1、2、…、N；
The controller is respectively connected with the reverse analog gating control port and the forward analog gating control port;
the input end of the analog-to-digital converter is connected with the output port, and the output end of the analog-to-digital converter is connected with the controller;
the piezoresistive sensorR ij And one end of the scanning portA i Connection of said piezoresistive sensorR ij And the other end of (2) and the sampling portB j Connection of said piezoresistive sensorR ij And the sampling portB j All provided with a controllable tri-state gate therebetweenC j Said controllable tri-state gateC j Are all connected with the controller; the piezoresistive sensorR ij Is connected with a nominal resistorR j ，j=1、2、…、N。
As a preferred solution, the piezoresistive sensorR ij And the scanning portA i Diodes are arranged between the two diodes.
As a preferred solution, the controllable tri-state gateC j Are all connected with the ground wire.
As a preferred solution, the nominal resistance isR j Is not more than
WhereinR 0Is one of the piezoresistive sensorsR ij Static resistance value in the no-pressure state.
As a preferred technical solution, the reverse analog gating control port and the forward analog gating control port both include a control word and/or an enable terminal, and the controller enables the voltage input port and one of the scan ports through the reverse analog gating control portA i The controller enables the output port to be communicated with one sampling port through the forward analog gating control portB j And (4) communicating.
In a second aspect, the present invention provides a circuit for measuring pressure distribution by a piezoresistive sensing array, comprising the steps of:
step A1, the controller controls the voltage input port of the inverse analog gating module to gate the output to the secondiA scanning portA i The controller controls the first of the forward analog gating modulesjA sampling portB j A strobe output to the output port,i=1，j=1；
step A2, the controller setting the tri-state gateC j Operating state of the gating circuit, the sampling portB j Said tri-state gate connectedC j The three-state gate is in a high impedance state, and other three-state gates are in a low impedance state;
step A3, the forward analog gating module gates the sampling portB j The analog voltage is output to the analog-to-digital converter;
step A4, the analog-to-digital converter sends digital signals to the controller to complete the piezoresistive sensorR ij Digital sampling of the pressure values of (a) and storing the data;
step A5, makingj=j+1, the forward analog gating module gates and outputs to the secondjA sampling portB j Repeating the steps A2-A4 until the resistance values of one row of the piezoresistive sensors are sampled;
step A6, makingi=i+1, the reverse analog gating module gates and outputs to the firstiA sampling portA i Repeating steps A1-A5 to complete the sampling of the resistance values of all the piezoresistive sensors in the piezoresistive sensor array;
step A7, calculating the pressure value of each piezoresistive sensor according to the mapping relation between the pressure and the resistance of the piezoresistive sensor; and repeating the steps A1-A6 to realize the real-time dynamic tracking of the pressure change of the piezoresistive sensor.
The beneficial effects of the invention are as follows:
1. the controller can enable the scanning port of the reverse analog gating module and the sampling port of the forward analog gating module to be communicated with each piezoresistive sensor in the piezoresistive sensor array, can simply and quickly measure the real-time resistance value of each piezoresistive sensor in the piezoresistive sensor array, can calculate the pressure of each piezoresistive sensor based on the pressure resistance mapping relation of the piezoresistive sensors, forms pressure distribution mapping based on the position of each piezoresistive sensor, and is high in scanning and sampling speed, small in measurement error, simple and easy in structure, low in cost and low in power consumption, and suitable for industrial application and popularization.
2. The invention increases the circuit discharge channel through the controllable three-state gate, improves the discharge speed, can improve the scanning frequency and the measurement speed on the premise of ensuring the measurement precision, and ensures the measurement instantaneity.
3. The invention can ensure the accuracy of measuring the resistance value of the piezoresistive sensor through the nominal resistor.
4. The invention can play a role of electrostatic protection through the diode between the piezoresistive sensor and the scanning port.
Drawings
FIG. 1 is a schematic structural diagram of a piezoresistive sensor array according to the present invention.
FIG. 2 is a schematic diagram of a piezoresistance mapping relationship of a piezoresistive sensor in accordance with the present invention.
FIG. 3 is a circuit diagram of a piezoresistive sensor array according to the present invention.
Fig. 4 is a functional block diagram of the present invention.
FIG. 5 is an equivalent circuit diagram of the present invention when measuring piezoresistive sensors.
FIG. 6 is a circuit diagram of an embodiment of the present invention.
In the figure: the sensor comprises a 1-piezoresistive sensing array, 11-piezoresistive sensors, a 2-reverse analog gating module, a 21-reverse analog gating control port, a 22-voltage input port, a 23-scanning port, a 3-forward analog gating module, a 31-forward analog gating control port, 311-control words, a 312-enable end, a 32-output port, a 33-sampling port, a 4-controller, a 5-analog-to-digital converter, a 6-controllable three-state gate, a 61-controllable three-state gate bus, a 7-nominal resistor and an 8-diode.
Detailed Description
In order to facilitate understanding for those skilled in the art, the present invention will be further described with reference to the accompanying drawings.
In a first aspect, referring to fig. 1-5, the present invention provides a circuit for measuring pressure distribution by a piezoresistive sensing array, comprising:
the piezoresistive sensing array 1 is composed of a piezoresistive sensing array 1M× N Piezoresistive sensors 11 distributed in an arrayR ij The composition of the components, wherein,Min the case of the number of rows,Nin order to count the number of columns,i=1、2、…、M，j=1、2、…、N；
the reverse analog gating module 2 is provided with a reverse analog gating control port 21, a voltage input port 22 and a voltage output port 22MA scanning port 23A i ，i=1、2、…、M；
The forward direction analog gating module 3 is provided with a forward direction analog gating control port 31, an output port 32 andNa sampling port 33B j ，j=1、2、…、N；
The controller 4 is connected with the reverse analog gating control port 21 and the forward analog gating control port 31 respectively;
the input end of the analog-to-digital converter 5 is connected with the output port 32, and the output end of the analog-to-digital converter 5 is connected with the controller 4;
piezoresistive sensor 11R ij And a scanning port 23A i Bonded, piezoresistive sensor 11R ij And the other end of the sampling port 33B j Bonded, piezoresistive sensor 11R ij And a sampling port 33B j Between all are provided with controllable tri-state gates 6C j Controllable tri-state gate 6C j Are all connected with a controller 4, in particular, the controller 4 is connected with a controller through a controllable threeThe state gate bus 61 is connected to the controllable three-state gate 6C j Connecting; piezoresistive sensor 11R ij Is connected with a nominal resistor 7R j ，j=1、2、…、NAnd the nominal resistances 7 are all grounded.
It should be noted that, as shown in fig. 1, piezoresistive sensors 11 in piezoresistive sensor array 1 shareMLine ofNThe rows are distributed in a regular rectangular array, however, in other embodiments, the piezoresistive sensor arrays 1 may be distributed in other forms (the piezoresistive sensors 11 inside the piezoresistive sensor arrays are numbered in the form of an array), and in order to achieve a good test effect, the piezoresistive sensors 11 should be distributed uniformly; as shown in FIG. 2, the resistance of an individual piezoresistive sensor 11 decreases with increasing pressure applied thereto, wherein when the piezoresistive sensor 11 is not subjected to pressure, the resistance of the piezoresistive sensor 11 is such thatR 0When the pressure applied to the piezoresistive sensors 11 is different, the resistance values of the piezoresistive sensors 11 are also different, and according to the mapping relationship, the pressure applied to the piezoresistive sensors 11 at the moment can be reversely deduced by measuring the real-time resistance values of the piezoresistive sensors 11, and further, the pressure distribution condition of the coverage area of the piezoresistive sensing array 1 can be deduced by measuring the values of all the piezoresistive sensors 11 in the piezoresistive sensing array 1; as shown in FIG. 3, the circuitry of piezoresistive sensor array 1 includesMLine circuit andNa column-column circuit for performing column-column operations,Mthe column circuit is sequentially connected withMThe individual scanning ports 23 are connected to each other,Nthe column circuit is in turn connected withNA sampling port 33 connected to the voltage resistance sensor 11R ij One end is connected with the firstiA scanning port 23A i Is connected at the other end withjA sampling port 33B j The connection is carried out by connecting the two parts,Nthe column circuits are each connected to a nominal resistor 7.
Based on the above embodiments, referring to fig. 4 and 6, the piezoresistive sensor 11R ij And a scanning port 23A i The diodes 8 are arranged between the two electrodes, and the diodes 8 can play a role in electrostatic protection.
On the basis of the above-mentioned embodiments, referring to fig. 4 and 6, the controllable tri-state gate 6C j Are all connected with the ground wire.
On the basis of the above-described embodiment, the nominal resistance 7R j Is not more than
WhereinR 0Is a piezoresistive sensor 11R ij Static resistance value in the no-pressure state.
On the basis of the above embodiment, referring to fig. 6, the reverse analog gating control port 21 and the forward analog gating control port 31 both include control words and/or enable terminals, and the controller 4 enables the voltage input port 22 and one scan port 23 through the reverse analog gating control port 21A i The controller 4 connects the output port 32 with a sampling port 33 through the forward analog strobe control port 31B j And (4) communicating.
In a second aspect, the present invention provides a circuit for measuring pressure distribution by a piezoresistive sensing array 1, comprising the steps of:
in step a1, the controller 4 controls the voltage input port 22 of the inverse analog gating module 2 to gate the output to the second voltage input portiA scanning port 23A i The controller 4 controls the second of the forward analog gating module 3jA sampling port 33B j The gated output is passed to the output port 32,i=1，j= 1; specifically, the inverse analog gating module 2 may include one or more inverse chips to ensure that the maximum number of gated channels supported by all the inverse chips is not less thanMLikewise, the forward analog gating module 3 may include one or more forward chips to ensure that the maximum number of gated channels supported by all the forward chips is not less thanN(ii) a Further, the input voltage of the voltage input port 22 is not greater than the sampling saturation voltage of the analog-to-digital converter 5, and optimally, the input voltage is the same as the sampling saturation voltage, so that higher precision and a larger dynamic range can be achieved;
step a2, controller 4 sets the tri-state gateC j Is enabled and enabled sampling port 33B j Connected IIIState doorC j The three-state gate is in a high impedance state, and other three-state gates are in a low impedance state; the tri-state gate can ground the sampling port 33 which is not used temporarily, so that a circuit discharge channel is added, the discharge speed is improved, the scanning frequency and the measurement speed can be improved on the premise of ensuring the measurement precision, and the measurement real-time performance is ensured;
step A3, the forward analog gating module 3 gates the sampling port 33B j The analog voltage is output to an analog-to-digital converter;
step A4, the analog-to-digital converter sends the digital signal to the controller 4 to complete the piezoresistive sensor 11R ij Digital sampling of the pressure values of (a) and storing the data;
step A5, makingj=j+1, the forward direction analog gating module 3 gates and outputs to the secondjA sampling port 33B j Repeating the steps A2-A4 until the pressure values of one row of piezoresistive sensors 11 are sampled;
step A6, makingi=i+1, the reverse analog gating module 2 gates and outputs to the secondiA sampling port 33A i Repeating the steps A1-A5 to complete the sampling of the pressure values of all the piezoresistive sensors 11 in the piezoresistive sensor array 1;
and step A7, calculating the pressure value of the piezoresistive sensor 11 according to the mapping relation between the pressure and the resistance of the piezoresistive sensor 11, and repeating the steps A1-A6 to realize the real-time dynamic tracking of the pressure change of the piezoresistive sensor 11.
The specific embodiment of the invention is as follows:
as shown in fig. 4, the controller 4 controls the inverse analog gating module 2 to gate the voltage of the voltage input port 22 to the inverse analog gating control port 21 (taking the control word as an example) and output the voltage to the inverse analog gating control port 21A 1-A M Is scanned over one of the scan ports 23 (typically fromA 1Start), the input voltage at the voltage input port 22 is determined according to the dynamic voltage range of the analog-to-digital converter 5, which is typically 3.3-12V in a common embodiment, and the controller 4 can change the control word at the inverse analog gating control port 21To alternately output the signal from the voltage input port 22 to the scan port 23A 1-A M Completing the line scanning of the piezoresistive sensing array 1; wherein the piezoresistive sensor 11R ij And a scanning port 23A i The diodes 8 are arranged between the piezoresistive sensing array and the scanning port 23 to isolate the piezoresistive sensing array 1 from the scanning port, so that static electricity can be prevented from entering the circuit of the piezoresistive sensing array 1 and being broken down, and an electrostatic protection effect can be achieved.
Similarly, the controller 4 controls the forward analog strobe module 3 via the forward analog strobe control port 31 (taking control word as an example)B 1-B N The analog voltage signals on the sampling ports 33 are sequentially gated and output to the analog-to-digital converter 5, so that the partial pressure sampling of each piezoresistive sensor 11 in the piezoresistive sensing array 1 is completed. Each sampling port 33 is grounded through a controllable three-state gate 6, and the controller 4 controls the state of the sampling port 33 to be a grounded fast discharge state or a partial voltage sampling state by adjusting the state of the controllable three-state gate 6. The analog-to-digital converter 5 converts the received analog voltage signal into a digital signal and sends the digital signal to the controller 4.
The controller 4 can be a single chip microcomputer or an FPGA, and the control time sequence of the controller 4 to each electronic component in the application is as follows:
in step B1, the controller 4 controls the inverse analog gating module 2 to gate the scan port 23A 1At this time, the process of the present invention,A 1is equal to the input voltage of the voltage input port 22, and the other scan ports 23A 2-A M No voltage output exists, and the circuit is in a suspended open circuit state;
in step B2, controller 4 controls and samples port 33B 1Connected controllable tri-state gate 6C 1In the high impedance state, and other controllable tri-state gates 6C 2-C N Are all in a low impedance state even though sampling port 33B 1Connected to ground via a standard resistor 7, and a further sampling port 33B 2-B N Are directly grounded through the controllable tri-state gate 6 in a low-resistance state;
step B3, controlThe controller 4 controls the forward analog gating module 3 to gate the sampling port 33B 1At this time, the analog-to-digital converter 5 may receive the sampling port 33B 1The output analog voltage signal is converted into a digital signal and sent to the controller 4;
in step B4, the controller 4 receives and stores the digital signal, and calculates the piezoresistive sensor array 1 according to the digital signalR 11The resistance value of (1);
step B5, sequentially circulating steps B2-B4, wherein in step 2, the sampling port 33 is sequentially arrangedB 2-B N Connected controllable tri-state gate 6C 2-C N The high impedance state, the other controllable three-state gate 6 is the low impedance state; in step 3, the sampling port 33 is sequentially gatedB 2-B N (ii) a The piezoresistive sensors 11 in the first row of piezoresistive sensor array 1 may be acquired sequentially in step 4R 12-R N1The resistance value of (1);
step B6, sequentially circulating steps B1-B5, wherein in step 1, the scanning port 23 is sequentially gatedA 2-A M To apply the voltage of the voltage input port 22 to the 2 nd-MThen, the 2 nd ion-channel of the piezoresistive sensing array 1 can be obtained in sequenceMThe resistance values of the piezoresistive sensors 11 of the row;
step B7, the controller 4 can calculate the pressure distribution on the piezoresistive sensor array 1 according to the pressure-resistance mapping relationship and the resistance value of each piezoresistive sensor 11; repeating steps B1-B6 may enable real-time dynamic tracking of each piezoresistive sensor 11 in piezoresistive sensor array 1, tracking dynamic changes in pressure across piezoresistive sensor array 1.
It should be noted that both the reverse analog gating module 2 and the forward analog gating module 3 may include one or more chips, so as to satisfy that the number of the scan ports 23 supported by the reverse analog gating module 2 is not less thanMThe number of sampling ports 33 supported by the forward analog gating module 3 is not less thanNThe method comprises the following steps of (1) taking; the input voltage at the voltage input port 22 is not greater than the sampled saturation voltage of the analog-to-digital converter 5 in order to achieve higher accuracyAnd a larger dynamic range, the input voltage of the voltage input port 22 is generally chosen to be the same as the sampled saturation voltage of the analog-to-digital converter 5; the sampling port 33 which is not used temporarily is grounded through the controllable three-state gate 6, which is equivalent to the increase of a discharge channel, the discharge speed is improved, on the premise of ensuring the measurement precision, the scanning frequency and the measurement speed of the sampling port 33 can be improved, the measurement real-time performance is ensured, compared with the time when the controllable three-state gate 6 is not used, only the sampling port 33 which is not used temporarily is in a suspended state, the discharge speed of the sampling port 33 in the scanning conversion process can be reduced, the time for the circuit to enter a stable state is increased, and the improvement of the measurement speed is influenced.
Wherein, when steps B1-B3 are completed, the equivalent circuit of the present invention is shown in fig. 5, and the portion in the dotted line area in fig. 5 is the interference resistance formed by the row-column intersection structure of the piezoresistive sensor array 1 itselfR δ WhereinR δ Of the order of magnitude of
At this time, the sampling voltage at the sampling port 33 is
WhereinV Ref Is the input voltage of the voltage input port 22,R s is the value of the nominal resistance 7,
is composed ofR s AndR δ the parallel resistance value of (a), specifically,
in the present invention, the above-described,R s should satisfy the resistance value
I.e. by
Herein, thisTime of flight
The sampling voltage at the sampling port 33 is
From which can be derivedR 11Has a resistance value of
To ensureR 11The accuracy of the measurement of (a), in the present invention,R s should satisfy
I.e. to ensure measurementR 11The measurement error of the resistance value of (1%) is less than.
In one embodiment of the present application, as shown in fig. 6, in this embodiment, the piezoresistive sensing array 1 is a pressure sensing film, the pressure sensing film is arranged in 16 rows and 32 columns, there are 512 piezoresistive sensors 11, each piezoresistive sensor 11 is a flexible film pressure sensor, the resistance between the row and column ports of the pressure sensing film is nearly infinite in the no-pressure state of the pressure sensing film, which can be considered as an open circuit state approximately, when a person with a weight of 70 kg stands on the pressure sensing film, the resistance of the flexible film pressure sensor contacting with the sole of the person is in the order of kilo ohms,R s is set to 30 kilo-ohms.
The reverse analog gating module 2 and the forward analog gating module 3 are both integrated circuits which support 16 analog gating interfaces to the maximum extent, so that in this embodiment, one reverse analog gating module 2 and two forward analog gating modules 3 are provided, 16 scanning ports 23 of the reverse analog gating module 2 are sequentially connected with 16 row interfaces of the piezoresistive sensor 11 through diodes 8, and 32 sampling ports 33 of the two reverse analog gating modules 2 are sequentially connected with 32 column interfaces of the piezoresistive sensor 11; specifically, the controller 4 passes a control word 311[ 2 ] of 4 bitsa 0,a 1,a 2,a 3]The voltage input port 22 of the inverse analog gating module 2 is controlled to communicate with one of the 16 scan ports 23, for example, when the control word 311 is [0,1,0,1 ]]The voltage input port 22 on the reverse analog gating module 2 and the scan port 23 on the 6 th rowA 6Communicating; the controller 4 passes a 4-bit control word 311[ 2 ]b 0,b 1,b 2,b 3]And enable terminals 312 on the two forward analog strobe modules 3e m ，m=1, 2, control the sending of the analog signal from one of the 32 sampling ports 33 to the analog-to-digital converter 5, in particular, when the enable terminal 312 on the forward analog gating module 3e m When =0, the forward analog gating module 3 is in a sleep state; when the forward analog strobe block 3 is enabled 312e m When =1, the forward analog gating module 3 is in a working state; the controller 4 controls the enable terminal 312 of the forward analog gating module 3 of a corresponding sampling port 33e m =1, and causes the control word 311[ ]b 0,b 1,b 2,b 3]The sampling port 33 can be opened corresponding to the sampling port 33.
The controller 4 sets the controllable tri-state gate 6 through the switch control wordC j Is high level or low level, specifically, the switch control word is set to be 32 bits, and the lowest bit (LSB) to the highest bit (MSB) respectively correspond to the controllable tri-state gates 6C 1-C 32For example, when the value of the switch control word corresponding to a controllable tri-state gate 6 is 0, the controllable tri-state gate 6 is in a high impedance state, and correspondingly, the output of the sampling port 33 corresponding to the controllable tri-state gate 6 is in a low level; conversely, when the value in the switch control word corresponding to a controllable tri-state gate 6 is 1, the controllable tri-state gate 6 is in a low impedance state, and accordingly, the output of the sampling port 33 corresponding to the controllable tri-state gate 6 is in a high level. For example, when the hexadecimal switch control word is oxFFFFFA, the corresponding binary is 1111,1111,1111,1010, and the values of LSB0 and LSB2 are 0, that is, the controllable tri-state gate 6 is nowC 1AndC 3is in a high impedance stateThe other controllable tri-state gates 6 are all in a low impedance state.
In this embodiment, the controller 4 is a single chip, and the specific control sequence of the single chip to each electronic component is as follows:
step C1, the singlechip sets the control worda 0,a 1,a 2,a 3]=[0,0,0,0]The output voltage of 5V is gated to the first row scanning port 23 of the pressure sensing film by the reverse analog gating module 2A 1；
Step C2, the single chip sets switch control word as oxFFFFFE through bus to make it connect with the sampling port 33B 1Connected controllable tri-state gate 6C 1In the high impedance state, and other controllable tri-state gates 6C 2-C N Are all in a low resistance state;
step C3, the single chip sete 1,e 2]=[0,1]The first forward analog gating module 3 is in working state, the second forward analog gating module 3 is in dormancy, and the singlechip sets the control word 311b 0,b 1,b 2,b 3]=[0,0,0,0]Controlling the first forward analog gating module 3 to gate the sampling port 33 of the pressure sensing membraneB 1The analog-to-digital converter 5 receives a sampling port 33B 1The output analog voltage signal is converted into a digital signal and sent to the singlechip;
step C4, the single chip receives and stores the digital signal, and calculates the pressure sensing film through the digital signalR 11The resistance value of (1);
and step C5, sequentially circulating the steps C2-C4, wherein in the step 2, the singlechip sequentially sets switch control words as oxFFFFFFFD, oxFFFFFFFC, … and ox7FFFFFFF through a controllable three-state gate bus 61, and sequentially enables the sampling port 33 to be connected with the sampling portB 2，B 3，…，B 16Connected controllable tri-state gate 6C 2，C 3，…，C 16Is in a high resistance state; in step 3, the sampling port 33 is sequentially providedB 2，B 3，…，B 16Corresponding control word 311[ 2 ]b 0,b 1,b 2,b 3]=[0,0,0,1],[0,0,1,0]，…[1,1,1,1]Then the singlechip sets the [ 2 ]e 1,e 2]=[1,0]The first forward analog gating module 3 is made to sleep, the second forward analog gating module 3 is made to be in a working state, and then the sampling port 33 is sequentially arrangedB 17，B 18，…，B 32Corresponding control word 311[ 2 ]b 0,b 1,b 2,b 3]=[0,0,0,0],[0,0,0,1]，…[1,1,1,1](ii) a The resistance values of the 32 flexible film pressure sensors in the first row in the pressure sensing film can be sequentially obtained in step 4;
step C6, the steps C1-C5 are circulated in sequence, wherein in the step 1, the singlechip is sequentially provided with and scans the port 23A 2，A 3，…，A 16Corresponding control word 311[ 2 ]a 0,a 1,a 2,a 3]=[0,0,0,1],[0,0,1,0]，…，[1,1,1,1]Sequentially gating the output voltage of 5V to the scanning ports 23 of the 2 nd to 16 th rows of the pressure sensing film; the step C5 is circulated, so that the resistance values of all the flexible film pressure sensors in the rows 2 to 16 in the pressure sensing film can be obtained in sequence;
step C7, the single chip microcomputer can calculate the pressure value information of each flexible film pressure sensor according to the pressure resistance mapping relation and the resistance value of each flexible film pressure sensor, and therefore a pressure distribution map on the pressure sensing film can be drawn; and C1-C6 are repeated, so that real-time dynamic tracking of each flexible film pressure sensor in the pressure sensing film can be realized, and dynamic tracking and analysis application of the pressure on the pressure sensing film can be realized.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. A circuit for measuring pressure distribution by a piezoresistive sensing array, comprising:
a piezoresistive sensing array consisting ofM×NArray distributed piezoresistive sensorR ij The composition of the components, wherein,Min the case of the number of rows,Nin order to count the number of columns,i=1、2、…、M，j=1、2、…、N；
the reverse analog gating module is provided with a reverse analog gating control port, a voltage input port andMa scanning portA i ，i=1、2、…、M；
The forward analog gating module is provided with a forward analog gating control port, an output port andNa sampling portB j ，j=1、2、…、N；
The controller is respectively connected with the reverse analog gating control port and the forward analog gating control port;
the input end of the analog-to-digital converter is connected with the output port, and the output end of the analog-to-digital converter is connected with the controller;
characterized in that the piezoresistive sensorR ij And one end of the scanning portA i Connection of said piezoresistive sensorR ij And the other end of (2) and the sampling portB j Connection of said piezoresistive sensorR ij And the sampling portB j All provided with a controllable tri-state gate therebetweenC j Said controllable tri-state gateC j Are all connected with the controller; the piezoresistive sensorR ij Is connected with a nominal resistorR j ，j=1、2、…、N；
The nominal resistanceR j Is not more than
WhereinR 0Is one of the piezoresistive sensorsR ij Static resistance value in the no-pressure state.
2. The circuit of claim 1, wherein the piezoresistive sensor array is configured to measure pressure distributionR ij And the scanning portA i Diodes are arranged between the two diodes.
3. The circuit of claim 1, wherein the controllable tri-state gate is configured to be coupled to a piezoresistive sensing arrayC j Are all connected with the ground wire.
4. The circuit of claim 1, wherein the reverse analog gating control port and the forward analog gating control port each include a control word and/or an enable terminal, and the controller connects the voltage input port to one of the scan ports via the reverse analog gating control portA i The controller enables the output port to be communicated with one sampling port through the forward analog gating control portB j And (4) communicating.
5. A method of measuring pressure distribution using the circuitry for measuring pressure distribution by piezoresistive sensing array according to claim 1, comprising the steps of:
step A1, the controller controls the voltage input port of the reverse analog gating module to gate the output to the second voltage input portiA scanning portA i The controller controls the first of the forward analog gating modulesjA sampling portB j The strobe output is passed to the output port,i=1，j=1；
step A2, controlThree state gate for setting deviceC j Operating state of the gating circuit, the sampling portB j Said tri-state gate connectedC j The three-state gate is in a high impedance state, and other three-state gates are in a low impedance state;
step A3, the forward analog gating module gates the sampling portB j The analog voltage is output to an analog-to-digital converter;
step A4, the analog-to-digital converter sends the digital signal to the controller to complete the piezoresistive sensorR ij Digital sampling of the pressure values of (a) and storing the data;
step A5, makingj=j+1, the forward analog gating module gates and outputs to the secondjA sampling portB j Repeating the steps A2-A4 until the resistance values of one row of the piezoresistive sensors are sampled;
step A6, makingi=i+1, the reverse analog gating module gates and outputs to the firstiA sampling portA i Repeating the steps A1-A5 to complete the sampling of the resistance values of all the piezoresistive sensors in the piezoresistive sensor array;
and A7, calculating the pressure value of the piezoresistive sensor according to the mapping relation between the pressure and the resistance of the piezoresistive sensor, and repeating the steps A1-A6 to realize the real-time dynamic tracking of the pressure change of the piezoresistive sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010379722.8A CN111289157B (en) | 2020-05-08 | 2020-05-08 | Circuit and method for measuring pressure distribution through piezoresistive sensing array |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010379722.8A CN111289157B (en) | 2020-05-08 | 2020-05-08 | Circuit and method for measuring pressure distribution through piezoresistive sensing array |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111289157A CN111289157A (en) | 2020-06-16 |
| CN111289157B true CN111289157B (en) | 2020-09-25 |
Family
ID=71019466
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010379722.8A Active CN111289157B (en) | 2020-05-08 | 2020-05-08 | Circuit and method for measuring pressure distribution through piezoresistive sensing array |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111289157B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112903151A (en) * | 2021-01-25 | 2021-06-04 | 华东师范大学 | Decoupling method suitable for thin film pressure sensor array and application thereof |
| CN114878033B (en) * | 2022-03-29 | 2023-12-22 | 深圳国微感知技术有限公司 | Matrix type pressure distribution measurement system and method |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8109149B2 (en) * | 2004-11-17 | 2012-02-07 | Lawrence Livermore National Security, Llc | Contact stress sensor |
| US9671297B2 (en) * | 2012-10-08 | 2017-06-06 | Stc. Unm | Pliable pressure-sensing fabric |
| WO2018044227A1 (en) * | 2016-06-30 | 2018-03-08 | Yoggzee Corporation Pte Ltd | Stretchable pressure mapping sysytem |
| CN107631818A (en) * | 2016-07-19 | 2018-01-26 | 中国科学院沈阳自动化研究所 | Flexible array pressure measurement sensor and its measuring method based on piezoresistive effect |
| CN108731853B (en) * | 2018-03-16 | 2020-08-25 | 东南大学 | Pressure distribution measurement and analysis system and method based on flexible material |
| CN110793680A (en) * | 2018-08-01 | 2020-02-14 | 西北农林科技大学 | Plantar pressure detection device |
| EP3850323A4 (en) * | 2018-09-12 | 2022-06-08 | Lenexa Medical Pty Ltd | Addressing circuit for conductor arrays |
| CN109489874B (en) * | 2019-01-16 | 2024-02-23 | 浙江理工大学 | Carbon fiber flexible pressure distribution sensing device and force measuring method thereof |
| CN110082010A (en) * | 2019-03-29 | 2019-08-02 | 中国科学院电子学研究所 | Flexible touch sensation sensor array and array scanning system applied to it |
| CN110108394B (en) * | 2019-05-20 | 2021-08-10 | 中国科学院重庆绿色智能技术研究院 | Large-area-array separated pressure sensor and preparation method thereof, and aqueous conductive slurry and preparation method thereof |
-
2020
- 2020-05-08 CN CN202010379722.8A patent/CN111289157B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN111289157A (en) | 2020-06-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US6720903B2 (en) | Method of operating SAR-type ADC and an ADC using the method | |
| CN111289157B (en) | Circuit and method for measuring pressure distribution through piezoresistive sensing array | |
| US6940271B2 (en) | Pin electronics interface circuit | |
| US5581252A (en) | Analog-to-digital conversion using comparator coupled capacitor digital-to-analog converters | |
| EP0832518A1 (en) | Dac having separate main and correcting outputs | |
| CN107346975A (en) | A kind of SAR types ADC high-precision calibration device | |
| CN110146178B (en) | Reading circuit and working method thereof | |
| CN113483923B (en) | Conditioning circuit and method for solving signal crosstalk and multipoint detection of flexible array piezoresistive sensor | |
| JPH08213911A (en) | Converter driven by current source | |
| CN105933004A (en) | Novel high-precision capacitor self-calibration analog-to-digital converter of successive approximation type | |
| CN111999565B (en) | Capacitance measuring circuit | |
| CN107356521B (en) | Detection device and method for micro current of multi-electrode array corrosion sensor | |
| CN113839673A (en) | Novel digital domain self-calibration successive approximation analog-to-digital converter | |
| CN105827244B (en) | Capacitor-resistor three-section successive approximation analog-to-digital converter with bridge capacitor as integer value | |
| US20130169456A1 (en) | Testing of analog-to-digital converters | |
| CN110032126B (en) | Multichannel strain signal synchronous acquisition system and method | |
| CN105978571A (en) | Successive approximation analog to digital converter suitable for single and double end input | |
| CN106059584A (en) | Sampling circuit and method for improving sampling resolution of sampling circuit | |
| CN106680690B (en) | Clock driving method for single-ended input and differential output applied to ATE (automatic test equipment) test | |
| CN115167597B (en) | Self-calibration method and device for bias driver in PJVS system | |
| KR20150072972A (en) | Analog to Digital Converter for interpolation using Calibration of Clock | |
| CN114861902A (en) | Processing unit, operation method thereof and computing chip | |
| CN112881856A (en) | Reconfigurable multi-mode sensor interface circuit | |
| CN217827842U (en) | Independent electrode module of modularized high-speed electrical impedance imaging device | |
| CN106569001B (en) | Low-power-consumption bridge array signal processing circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20200821 Address after: 261599 Area 37, North Industrial Park, Xiazhuang Town, Gaomi City, Weifang City, Shandong Province Applicant after: SHANDONG HUAHUI HOME TECHNOLOGY Co.,Ltd. Address before: 261599 Area 37, North Industrial Park, Xiazhuang Town, Gaomi City, Weifang City, Shandong Province Applicant before: Shandong Aiao Intelligent Technology Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| PE01 | Entry into force of the registration of the contract for pledge of patent right | ||
| PE01 | Entry into force of the registration of the contract for pledge of patent right |
Denomination of invention: A circuit and method for measuring pressure distribution through a piezoresistive sensing array Effective date of registration: 20230905 Granted publication date: 20200925 Pledgee: Shandong Gaomi rural commercial bank Limited by Share Ltd. Pledgor: SHANDONG HUAHUI HOME TECHNOLOGY CO.,LTD. Registration number: Y2023980055344 |