CN208140017U - Metal microspur measurement sensor and measuring system - Google Patents
Metal microspur measurement sensor and measuring system Download PDFInfo
- Publication number
- CN208140017U CN208140017U CN201721705209.3U CN201721705209U CN208140017U CN 208140017 U CN208140017 U CN 208140017U CN 201721705209 U CN201721705209 U CN 201721705209U CN 208140017 U CN208140017 U CN 208140017U
- Authority
- CN
- China
- Prior art keywords
- capacitor
- metal
- circuit
- resistance
- triode
- 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
Landscapes
- Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
Abstract
The utility model provides metal microspur measurement sensor and measuring system, which includes capacitance test side, signal amplification and shaping unit, measurement and calculating end, is tested between two poles of metal object, there are an interelectrode capacities.In transducer tip, we access this interelectrode capacity oscillating circuit, then generate the oscillator signal of a certain frequency, the signal is accessed amplification and shaping circuit again, it carries out frequency measurement with the signal after shaping, access FPGA circuitry by amplifying, curve matching, calculate distance, finally again calculated distance value, by SPI interface, export to other main control devices, such as metal-working plant, metal spare and accessory parts assembly equipment etc..The metal microspur measurement sensor realized using the above thinking, low in cost, measurement and calculating time are shorter, and precision is not influenced by working environment, are highly suitable for the industries such as intermetallic composite coating, the assembly of metal spare and accessory parts.
Description
Technical field
The utility model relates to analyze and survey control technology field, in particular to a kind of high-speed, high precision metal microspur is surveyed
Quantity sensor.
Background technique
Traditional slight distance measurement method is using capacitance method, inductance method, tellurometer survey method, laser ranging method etc..Its
In, inductance method, tellurometer survey method precision in laser cutting application is inadequate, and laser ranging method is easy stimulated light and processing igniting again
Flower influences, and is unable to reliability application；Capacitance method is two faces (or a point and another face) metal to be measured, regards two as
, there is a capacitor in a electrode, which is C=ε S/d between the two electrodes.(wherein Jie of ε medium between pole plate
Electric constant, S are polar plate area, distance of the d between pole plate.) according to formula above it is found that between capacitor C1 pole plate spacing away from
From bigger, capacitance is smaller, i.e. the distance between capacitor C1 pole plate spacing, the size with capacitance, there are corresponding relationship, this
Measurement distance can be converted to measurement capacitor by sample, but what is solved first is how to measure two capacitor C1 pole plate spacing
Between equivalent capacity capacitance.
Utility model content
Present patent application provides metal microspur measurement sensors, and collected capacitance variations data are carried out curve fitting
Processing obtains the functional relation of the equivalent capacitance value and distance between two metal coverings, including resonance circuit, switch amplification electricity
Road, operational amplifier circuit, the switch input amplifier connect with resonance circuit, export termination switch amplifying circuit；Resonance electricity
The RLC resonance circuit that road is constituted using inductance L1, resistance R2 and detected capacitor C1；It switchs and uses NPN ditch in amplifying circuit
The triode Q1 in road, the collector of triode Q1 connect inductance L1 and the connection common end of resistance R2, base stage in RLC resonance circuit and connect
The variation of pull-up resistor R1, measured capacitance C1 cause the variation of current collection electrode potential, control the switch of triode Q1；Operational amplifier circuit
Using reversed operational amplifier circuit, the collector terminal of triode Q1 is followed by the reversed input of the transport and placing device U1 of operational amplifier circuit by capacitor C3
End amplifies detection signal.
Preferably, in resonance circuit, capacitor C1 cathode ground connection, anode meet inductance L1, another terminating resistor R2 of inductance L1,
The other end of resistance R2 draws power supply；The pole plate of capacitor C1 is metal polar plate.
Preferably, it switchs in amplifying circuit, the base stage of triode Q1 also connects the RC filter being made of resistance R5, capacitor C7 parallel connection
Wave circuit, the emitter of triode Q1 meet pull down resistor R7, and the indirect capacitor C6 of emitter and collector, capacitor C8 are connected in parallel on electricity
The resistance both ends R7 also constitute RC filter circuit.
Preferably, in operational amplifier circuit, the positive input IN+ of transport and placing device meets capacitor C3, output end and reverse input end IN-
The public termination electricity of connecting resistance R6, resistance R6 and reverse input end IN- public termination pull down resistor R8, resistance R6 and transport and placing device U1
Hold C4, another termination pull down resistor R4 and capacitor C5 of another terminating resistor R3 of capacitor C4, R3.
A kind of measuring system using the sensor further includes FPGA and main control device including above-mentioned sensor,
FPGA input termination sensor, calculates the capacitor C1 changing value of sensor measurement, output is to main control device after calculating.
A kind of measurement method, within FPGA each clock cycle, sensor measurement to M signal value point, M signal value
Point is pi (xi, yi), wherein i=1,2 ..., m；In X clock periodicity, for calculating capacity substrate spacing L；Using minimum
The curve that M signal of square law degree is constituted carries out curve fitting, and chooses the curve of approximation y=φ of the curve y=f (x) of M signal
(x), deviation δ i=φ (xi)-y, i=1,2 ..., m of the curve of approximation at point pi；S1. set polynomial fitting as：
Y=a0+a1x+...+akxk,
S2. each point is as follows to the sum of the distance of this curve, i.e. sum of square of deviations：
S3. in order to acquire qualified a value, ai partial derivative is sought on peer-to-peer the right, thus we obtain：
S4. the equation left side is subjected to abbreviation, it then should available following equation：
S5. these equatioies are expressed as the form of matrix, so that it may obtain following matrix：
S6. it can be obtained after this vandermonde being obtained matrix abbreviation:
S7. that is X*A=Y, then A=(X'*X) -1*X'*Y, has just obtained coefficient matrices A, meanwhile, Wo Menye
Matched curve is just obtained.
The beneficial effects of the utility model：The interelectrode capacity between two metals, oscillating circuit is accessed.Oscillator signal warp
After crossing amplification and shaping, FPGA is accessed.FPGA can undergo certain FPGA during capturing the external pulse of fixed number
The numerical value of system clock cycle number, the system clock cycle number corresponds to the frequency of external pulse.It is entire by learning and measuring
System clock cycle number in distance range, to obtain the numerical value of the system clock cycle number in the distance range and pair of distance
It should be related to.The corresponding relationship can be indicated with the form of curve, to the curve Function Fitting, obtain the distance measuring sensor
The corresponding relationship of oscillation signal frequency value and distance.In actual work, it need to can only be calculated according to the frequency values of oscillator signal
Then target range exports the distance value to main control device by SPI interface.The metal microspur that the thinking is realized, which measures, to be passed
Sensor, low in cost, measurement and calculating time are shorter, and precision is not influenced by working environment.
Detailed description of the invention
Fig. 1 is circuit diagram of the present patent application present patent application about sensor circuit；
Fig. 2 is principle framework figure of the present patent application about this patent；
Fig. 3 is curve of the present patent application about the actual measured value of the capacitor plate spacing of sensor measurement；
Fig. 4 is by FPGA to the matched curve after the actual measurement profile fitting of Fig. 3.
Specific embodiment
Shown in Fig. 1, present patent application provides a kind of sensor circuit, carries out capacitor oscillation frequency using sensor circuit
Test, sensor detection circuit use RLC resonance circuit by resonance circuit, switch amplifying circuit, operational amplifier circuit, resonance circuit,
It is made of detected capacitor C1, inductance L1, resistance R2, capacitor C1 cathode ground connection, anode meet inductance L1, and inductance L1's is another
The other end of terminating resistor R2, resistance R2 draw power supply；Capacitor C1 be it is adjustable, the effect of capacitor C1 in this patent be by
Detecting element, the electrode plate of capacitor C1 use metal material, the electrode plate distance of capacitor C1, pole plate relative area variation with
And the variation of plate medium can all cause the faint variation of resonance circuit.
Amplifying circuit is switched by triode Q1, resistance R1, R5, R7, capacitor C6, C7, C8, resistance R5, capacitor C7 parallel connection structure
At RC filter circuit, RC filter circuit one end ground connection, the other end connects pull-up resistor R1 and triode Q1 base stage, triode Q1 are adopted
With NPN channel, the common end of the collector connecting resistance R2 and inductance L1 of triode Q1, emitter connect pull down resistor R7, triode
The indirect capacitor C6 of Q1 emitter and collector, capacitor C8 are connected in parallel on the both ends resistance R7 and also constitute RC filter circuit.
Inductance L1, capacitor C6, resistance R2 and triode Q1 collector public termination capacitor C3, capacitor C3's
Another termination operational amplifier circuit.
Operational amplifier circuit uses reversed operational amplifier circuit, including：Transport and placing device U1, capacitor C2, C4, C5, resistance R6, R8, R4, R3,
Transport and placing device U1 connects power supply, and the positive input IN+ of transport and placing device meets capacitor C3, output end and reverse input end IN- connecting resistance R6, electricity
R6 and the public termination pull down resistor R8 of reverse input end IN-, resistance R6 and the public termination capacitor C4 of transport and placing device U1 are hindered, capacitor C4's
Another termination pull down resistor R4 and capacitor C5 of another terminating resistor R3, R3.
The sensor detection circuit is measured in real time the variation of adjustable condenser C1, i.e.,：Using above-mentioned hardware electricity
The sensor on road, the frequency of oscillator signal, the i.e. frequency of capacitor measured signal, with two capacitor C1 pole plate distances
Variation, faint variation occurs for the frequency of measured signal, if two capacitor C1 pole plate spacing are in contact, measured signal
Frequency, change dramatically are simultaneously handled by amplification switch circuit and operational amplifier circuit, are calculated after processing using FPGA.
Shown in Fig. 2, the present patent application also provide a kind of frequency measuring system, including above-mentioned sensor measuring circuit,
FPGA and main control device further include：Capacitance test side, signal amplification and shaping unit, measurement and calculating end,
There are an interelectrode capacities between two poles of tested metal object, and in transducer tip, we are this interelectrode capacity, access
Oscillating circuit, then generates the oscillator signal of a certain frequency, then the signal is accessed amplification and shaping circuit, by amplification and whole
Signal after shape accesses FPGA circuitry, carries out frequency measurement, curve matching, calculates distance, finally again calculated distance
Value is exported by SPI interface to other main control devices, such as metal-working plant, metal spare and accessory parts assembly equipment etc..
Conventional frequency measuring method, that is, measure the interval between the rising edge of two neighboring measured signal, with measured signal
For 2MHz, period 500ns, if we are measured with the time scale of 5ns, worst error is less than two FPGA's
The system period, that is, it is less than 10ns, error rate 10/500=2%, so big error rate not can guarantee system accuracy.
The present patent application also provide a kind of frequency measurements to calculate method, and oscillator signal is accessed by amplifying with after shaping
FPGA, FPGA can undergo certain FPGA system clock periodicity, this is during capturing the external pulse of fixed number
The numerical value of system clock periodicity corresponds to the frequency of external pulse, we are by study and measure the system in entire distance range
Clock periodicity, to obtain the numerical value of the system clock cycle number in the distance range and the corresponding relationship of distance, which is closed
System can indicate that the curve is the intrinsic curve of sensor, the shape of the curve with the form of curve, only with sensor itself
Characteristic it is related, will not because of working environment variation and change, when temperature, humidity etc. change, only need to be to the curve
Make translation amendment.
For further, the measurement method be by measure two neighboring measured signal rising edge (i.e. 1 period) it
Between interval realize that, if measured signal has continuous N number of period, we can pass through the upper of measurement two signals of head and the tail
The interval on edge is risen, to calculate the frequency of single measured signal, then error rate=2%/N at this moment, that is, precision improve
N times.
The pulse signal of acquisition sensor measuring circuit in the FPGA clock cycle, if：M signal is collected in clock cycle
It is worth point, shares X clock periodicity, for calculating capacity substrate spacing L, wherein the coordinate information of each signaling point is (x, y),
The curve of capacitance and distance is carried out curve fitting using least square method multinomial, according to m given point, it is not required that this
Curve accurately passes through these points, but the curve of approximation y=φ (x) of curve y=f (x), data-oriented point pi (xi,
Yi), wherein i=1,2 ..., m, seek curve of approximation y=φ (x), and make the deviation of curve of approximation and y=f (x) minimum,
Deviation δ i=φ (xi)-y, i=1,2 ..., m of the curve of approximation at point pi.
Common curve-fitting method:
1. making the sum of absolute value of the bias minimum
2. making the maximum minimum of absolute value of the bias
3. keeping sum of square of deviations minimum
Matched curve is chosen by the smallest principle of sum of square of deviations, and taking binomial equation is the side of matched curve
Method, referred to as least square method.
Derivation process：
1. set polynomial fitting as：
Y=a0+a1x+...+akxk,
2. each point is as follows to the sum of the distance of this curve, i.e. sum of square of deviations：
3. ai partial derivative is sought on the right of peer-to-peer in order to acquire qualified a value, thus we obtain：
4. the equation left side is subjected to abbreviation, it then should available following equation：
5. the form that these equatioies are expressed as matrix, so that it may obtain following matrix：
6. can be obtained after this vandermonde is obtained matrix abbreviation:
7. that is X*A=Y, then A=(X'*X) -1*X'*Y, has just obtained coefficient matrices A, meanwhile, we are also
Matched curve is obtained.
The curve that we arrive study obtains the oscillation signal frequency value and distance of the distance measuring sensor with Function Fitting
Corresponding relationship, in actual work, only need to can calculate target range according to the frequency values of oscillator signal, then this away from
It is exported by SPI interface to main control device from value.
The metal microspur measurement sensor realized using the above thinking, low in cost, measurement and calculating time are shorter, precision
It is not influenced by working environment, is highly suitable for the industries such as intermetallic composite coating, the assembly of metal spare and accessory parts.
The principles and effects of present patent application are only illustrated in above-described embodiment, not for limitation this patent Shen
Please.Any person skilled in the art can all carry out above-described embodiment under the spirit and scope without prejudice to present patent application
Modifications and changes.Therefore, such as those of ordinary skill in the art without departing from the revealed essence of present patent application
All lamps effect modifications and changes completed under mind and technical idea, the claim that should be asked by this patent are covered.
Claims (5)
1. metal microspur measurement sensor, it is characterised in that：It is described to open including resonance circuit, switch amplifying circuit, operational amplifier circuit
Input amplifier is closed to connect with resonance circuit, export termination switch amplifying circuit；Resonance circuit uses inductance L1, resistance R2
The RLC resonance circuit constituted with detected capacitor C1；Switch the triode Q1 that NPN channel is used in amplifying circuit, triode
The collector of Q1 connects inductance L1 and the connection common end of resistance R2, base stage in RLC resonance circuit and connects pull-up resistor R1, measured capacitance
The variation of C1 causes the variation of current collection electrode potential, controls the switch of triode Q1；Operational amplifier circuit uses reversed operational amplifier circuit, three poles
The collector terminal of pipe Q1 is followed by the reverse input end of the transport and placing device U1 of operational amplifier circuit by capacitor C3, puts to detection signal
Greatly.
2. metal microspur measurement sensor according to claim 1, it is characterised in that：In resonance circuit, capacitor C1 cathode
Ground connection, anode meet inductance L1, another terminating resistor R2 of inductance L1, and the other end of resistance R2 draws power supply；The pole plate of capacitor C1 is
Metal polar plate.
3. metal microspur measurement sensor according to claim 1, it is characterised in that：It switchs in amplifying circuit, triode
The base stage of Q1 also connects the RC filter circuit being made of resistance R5, capacitor C7 parallel connection, and the emitter of triode Q1 meets pull down resistor R7,
The indirect capacitor C6 of emitter and collector, capacitor C8 are connected in parallel on the both ends resistance R7 and also constitute RC filter circuit.
4. metal microspur measurement sensor according to claim 1, it is characterised in that：In operational amplifier circuit, transport and placing device is just
Capacitor C3, output end and the common end reverse input end IN- connecting resistance R6, resistance R6 and reverse input end IN- are connect to input terminal IN+
Connect the public termination capacitor C4 of pull down resistor R8, resistance R6 and transport and placing device U1, another terminating resistor R3 of capacitor C4, the other end of R3
Meet pull down resistor R4 and capacitor C5.
5. a kind of measuring system using sensor described in Claims 1-4 any claim, it is characterised in that：Packet
Above-mentioned sensor is included, further includes FPGA and main control device, FPGA input termination sensor becomes the capacitor C1 of sensor measurement
Change value is calculated, and output is to main control device after calculating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721705209.3U CN208140017U (en) | 2017-12-11 | 2017-12-11 | Metal microspur measurement sensor and measuring system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721705209.3U CN208140017U (en) | 2017-12-11 | 2017-12-11 | Metal microspur measurement sensor and measuring system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN208140017U true CN208140017U (en) | 2018-11-23 |
Family
ID=64284693
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721705209.3U Active CN208140017U (en) | 2017-12-11 | 2017-12-11 | Metal microspur measurement sensor and measuring system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN208140017U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112400143A (en) * | 2019-08-02 | 2021-02-23 | 深圳市越疆科技有限公司 | Sensing circuit, logic circuit board, joint control board, main controller board and robot |
-
2017
- 2017-12-11 CN CN201721705209.3U patent/CN208140017U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112400143A (en) * | 2019-08-02 | 2021-02-23 | 深圳市越疆科技有限公司 | Sensing circuit, logic circuit board, joint control board, main controller board and robot |
| CN112400143B (en) * | 2019-08-02 | 2023-09-08 | 深圳市越疆科技股份有限公司 | Sensing circuit, logic circuit board, joint control board, master controller board and robot |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108020153A (en) | Metal microspur measurement sensor, measuring system and measuring method | |
| CN103995024B (en) | A kind of measuring method of the circuit for resistance-type Water content measurement sensor | |
| CN204101635U (en) | A kind of microresistivity survey instrument and electronic product process units | |
| CN106442235A (en) | Pesticide droplet deposition and evaporation detection device and method | |
| CN104880597A (en) | Programmable logic circuit based weak signal detection method | |
| CN100516856C (en) | Intelligent testing system for moisture of cotton fiber | |
| CN112213554A (en) | Weak current measuring circuit and method based on current frequency conversion method | |
| CN208140017U (en) | Metal microspur measurement sensor and measuring system | |
| CN101487811B (en) | Static sounding resistivity probe | |
| CN104916083A (en) | Internet of things based intelligent combustible gas inspection detector and calibration method thereof | |
| CN103335588A (en) | Deformation measurement method for equipment housing of high-pressure closed vessel | |
| CN107228886B (en) | The measuring device and method of the conductivity Resistivity testing of water | |
| CN105203979A (en) | Electrostatic direction finding system | |
| CN102206996A (en) | Weak signal detector | |
| CN103984004B (en) | A kind of method of automatic elimination PIPS alpha energy spectrum peak temperature drift and device | |
| CN109581062A (en) | High-precision impedance measurement system for oscilloscope calibrator probe | |
| CN108680616A (en) | A kind of humidity sensing device and method of digitized processing | |
| CN101782418A (en) | Non-contact capacitance liquid level meter | |
| CN101441236A (en) | Capacity sensor circuit based on Wien bridge and phase-locked loop | |
| CN203414434U (en) | Circuit for resistance-type water measurement sensor | |
| CN106841751B (en) | Voltage rise and fall quantitative detection circuit/device | |
| CN102192951A (en) | Ion concentration measuring circuit and ion current sensor | |
| CN112747797B (en) | Flow metering circuit | |
| CN103457558A (en) | Variable gain low current picking and amplifying circuit | |
| CN113552529A (en) | Self-calibration system and method based on intelligent electric energy meter online monitoring |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |