CN109959479B - Outer cantilever anchoring force calibration system - Google Patents
Outer cantilever anchoring force calibration system Download PDFInfo
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- CN109959479B CN109959479B CN201910304449.XA CN201910304449A CN109959479B CN 109959479 B CN109959479 B CN 109959479B CN 201910304449 A CN201910304449 A CN 201910304449A CN 109959479 B CN109959479 B CN 109959479B
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- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L25/00—Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
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Abstract
The invention provides an outer cantilever anchoring force calibration system, which calibrates the outer cantilever anchoring force of a double-limb thin-wall pier by utilizing a central processing unit, a theoretical value input end, an analysis end, a force sensor, a signal processing circuit, a temperature sensor, a comparison module and a display, compares the outer cantilever anchoring force calculated theoretically with the outer cantilever anchoring force measured by the sensor to know whether the outer cantilever anchoring force test is accurate, and collects temperature information of a test field through the temperature sensor so as to enable a worker to clearly see the field environment temperature during the outer cantilever anchoring force test.
Description
Technical Field
The invention relates to the field of intelligent testing, in particular to an outer cantilever anchoring force calibration system.
Background
The third and fourth joints of the main line viaduct of a certain urban loop road project are 55+3 multiplied by 100+55m continuous rigid frames which are arranged for crossing a planned road. The relief of the bridge area is large. The bridge is positioned in a road flat curve, R =1270m, the bridge deck system changes along with the curve, the longitudinal slope of the bridge is 3%, and the transverse slope of the bridge is 1.5%. The third and the fourth joints are divided into a left part and a right part, and the main beam and the lower structure are independent. The upper structure of the bridge adopts a prestressed concrete continuous rigid frame, the lower main pier adopts a double-limb thin-wall pier, the approach bridge transition pier adopts a hollow pier, and the foundation adopts a pile foundation plus bearing platform form.
The test of the anchoring force of the outer cantilever is crucial to the safety of the double-limb thin-wall pier, but in the prior art, only the anchoring force of the outer cantilever is tested, and the anchoring force of the outer cantilever cannot be efficiently and accurately calibrated, so that whether the obtained anchoring force of the outer cantilever is accurate cannot be known.
In this regard, it is desirable to provide an outer cantilever anchoring force calibration system.
Disclosure of Invention
Therefore, in order to overcome the above problems, the present invention provides an external cantilever anchoring force calibration system, which utilizes a central processing unit, a theoretical value input terminal, an analysis terminal, a force sensor, a signal processing circuit, a temperature sensor, a comparison module and a display to calibrate the external cantilever anchoring force of a double-limb thin-wall pier, comparing the anchoring force of the outer cantilever calculated by theory with the anchoring force of the outer cantilever measured by a sensor to know whether the testing of the anchoring force of the outer cantilever is accurate, and the temperature information of the test site is collected by the temperature sensor, so that the working personnel can clearly know the site environment temperature when the anchoring force of the outer cantilever is tested, wherein, adopt the mode of equipartition line load conversion to calculate outer cantilever anchoring force in the theoretical calculation, when using the sensor to gather outer cantilever anchoring force, make the data that record more accurate through signal processing circuit.
The invention provides an outer cantilever anchoring force calibration system which comprises a central processing unit, a theoretical value input end, an analysis end, a force sensor, a signal processing circuit, a temperature sensor, a comparison module and a display.
The output end of the theoretical value input end is connected with the input end of the analysis end, the output end of the force sensor is connected with the input end of the signal processing circuit, the output end of the analysis end, the output end of the signal processing circuit and the output end of the temperature sensor are connected with the input end of the central processing unit, the input end of the comparison module and the input end of the display are connected with the output end of the central processing unit, and the output end of the comparison module is connected with the input end of the display.
The theoretical value input end is used for inputting parameters for calculating the anchoring force of the outer cantilever under the load, and the analysis end is used for calculating the anchoring force F of the outer cantilever under the load according to the parameters for calculating the anchoring force of the outer cantilever under the load and input in the theoretical value input endBThe force sensor is arranged at a stress point of the anchoring point and used for detecting an anchoring force signal of the outer cantilever under load, the signal processing circuit is used for processing the anchoring force acquired by the force sensor and transmitting the processed force signal F to the central processing device, the temperature sensor is used for detecting a temperature signal of a test site, and the central processing device is used for receiving the anchoring force FBAnd transmitting the anchoring force F to a comparison module for transmitting the anchoring force FBComparing the anchoring force F with the anchoring force F, transmitting the comparison result to a display for displaying, and using the central processing device to receive the anchoring force FBAnd transmitting the anchoring force F and the temperature signal to a display for displaying.
Preferably, the theoretical value input end is used for inputting a parameter for calculating the anchoring force of the outer cantilever under the load into the load of the outer cantilever
The analysis end is used for calculating the anchoring force F of the outer cantilever under the load according to the parameter which is input from the theoretical value input end and used for calculating the anchoring force of the outer cantilever under the loadBThe method comprises the following steps:
and S1, equivalently converting the force: the load of the single-side outer cantilever is shared by 4 groups of brackets, so that the single group of brackets bears the load
In the formula (I), wherein,
representing the load of the single-group outer bracket, and 1.1 is a load safety coefficient;
s2, uniform line load conversion: single-group outer bracket load is converted into uniform distribution line load
In the formula (I), wherein,Lacting length for outer bracket load;
s3, determining a prepressing point, converting the uniform distribution line load into a concentrated load, and determining the position of the prepressing point:
wherein x represents the distance from the prepressing point to the anchoring point;
s4, calculating the anchoring force F of the outer cantilever under the load according to the distance x between the pre-pressing point and the anchoring point obtained by the calculationBWherein the fixed point and the prepressing point are respectively arranged at two sides of the anchoring point, the distance between the fixed point and the anchoring point is y, and the analysis end obtains the anchoring force of the outer cantilever under the load
；
S5, the analysis end anchors the outer cantilever under load to obtain the anchoring force FBAnd transmitting to the central processing unit.
Preferably, the force sensor is arranged at an anchoring point stress point and used for detecting an anchoring force signal of the outer cantilever under a load, and the signal processing circuit sequentially performs signal amplification and signal filtering processing on the anchoring force acquired by the force sensor.
Preferably, the force sensor is used for detecting an anchoring force signal of the outer cantilever under a load, converting the collected force signal into a voltage signal V0, and transmitting the voltage signal V0 to the signal processing circuit, wherein V1 is the voltage signal processed by the signal processing circuit, the signal processing circuit comprises a signal amplifying unit and a signal filtering unit, an output end of the force sensor is connected with an input end of the signal amplifying unit, an output end of the signal amplifying unit is connected with an input end of the signal filtering unit, and an output end of the signal filtering unit is connected with an input end of the central processing unit.
Preferably, the signal amplification unit comprises an integrated operational amplifier A1-A2, a capacitor C1-C6, a triode VT1-VT2, a voltage regulator tube D1-D2 and a resistor R1-R9, wherein a first pin of the integrated operational amplifier A1 and the integrated operational amplifier A2 is an-IN pin, a second pin of the integrated operational amplifier A1 and the integrated operational amplifier A2 is a + IN pin, a third pin of the integrated operational amplifier A COMP pin, a fourth pin of the integrated operational amplifier A V + pin, a fifth pin of the integrated operational amplifier A S/D pin, a sixth pin of the integrated operational amplifier A1 and the integrated operational amplifier A2 is a V-IN pin, a seventh pin of the integrated operational amplifier A + IN pin is an OUT pin, a eighth pin of the integrated operational amplifier A NC pin is an NC pin.
Wherein, the output end of the force sensor is connected with one end of a resistor R2, one end of a resistor R1 is grounded, the other end of a resistor R1 is connected with one end of a resistor R2, the other end of a resistor R2 is connected with a first pin of an integrated operational amplifier A1, the other end of a resistor R2 is also connected with one end of a resistor R3, a second pin of an integrated operational amplifier A1 is grounded, one end of a capacitor C2 is grounded, the other end of a capacitor C2 is connected with one end of a resistor R4, the other end of a capacitor C2 is also connected with a-15V power supply, a sixth pin of an integrated operational amplifier A1 is connected with a-15V power supply, the other end of a resistor R4 is connected with a third pin of an integrated operational amplifier A1, a fourth pin of the integrated operational amplifier A1 is connected with a +15V power supply, one end of a capacitor C1 is grounded, the other end of a capacitor C1 is connected with a +15V power supply, the other end of a resistor R3 is connected with the other end of a capacitor C5, the other end of a resistor R3 is also connected with an anode voltage regulator 1, the cathode of a voltage regulator tube D1 is connected with the base of a triode VT1, the cathode of a voltage regulator tube D1 is also connected with one end of a resistor R5, the other end of the resistor R5 is connected with a +30V power supply, the other end of the resistor R5 is also connected with the collector of a triode VT1, the other end of a capacitor C5 is also connected with the emitter of the triode VT1, one end of a capacitor C3 is connected with the cathode of the voltage regulator tube D2, one end of a capacitor C3 is also connected with one end of the capacitor C6, the other end of a capacitor C3 is connected with the fifth pin of the integrated operational amplifier, the anode of the voltage regulator tube D2 is connected with the base of the triode VT2, the anode of the voltage regulator tube D2 is also connected with one end of the resistor R7, the other end of the resistor R7 is connected with a-30V power supply, the other end of the resistor R7 is also connected with the collector of the triode VT2, the other end of the resistor R3 is also connected with the seventh pin of the integrated operational amplifier A1, one end of the capacitor C6 is also connected with the seventh pin of the integrated operational amplifier 1, a seventh pin of the integrated operational amplifier a1 is connected to the 2 nd pin of the integrated operational amplifier a2, the other end of the capacitor C5 is further connected to the fourth pin of the integrated operational amplifier a2, the first pin of the integrated operational amplifier a2 is connected to one end of the resistor R8, the other end of the resistor R8 is grounded, the other end of the capacitor C6 is connected to one end of the resistor R6, the other end of the resistor R6 is connected to the third pin of the integrated operational amplifier a2, one end of the resistor R6 is further connected to an emitter of the transistor VT2, an emitter of the transistor VT2 is connected to the sixth pin of the integrated operational amplifier a2, a collector of the transistor VT2 is connected to a-30V power supply, one end of the capacitor C4 is connected to the fifth pin of the integrated operational amplifier a2, the other end of the capacitor C4 is connected to one end of the resistor R9, the other end of the capacitor C4 is further connected to the seventh pin of the integrated operational amplifier a2, and a 7 of the integrated operational amplifier a2 is connected to the input terminal of the signal filtering unit.
Preferably, the signal filtering unit comprises resistors R10-R16, capacitors C7-C12 and an integrated operational amplifier A3.
Wherein, the output end of the signal amplification unit is connected with one end of a resistor R10, the other end of a resistor R10 is connected with the inverting input end of an integrated operational amplifier A3, the non-inverting input end of the integrated operational amplifier A3 is grounded, the other end of a resistor R10 is also connected with one end of a resistor R11, the other end of a resistor R11 is connected with the output end of an integrated operational amplifier A3, one end of a resistor R12 is connected with one end of a resistor R11, one end of a resistor R13 is connected with one end of a resistor R11, one end of a capacitor C7 is connected with one end of a resistor R11, the other end of a capacitor C7 is connected with the output end of an integrated operational amplifier A3, the other end of a resistor R3 is connected with one end of a capacitor C3, the other end of the resistor R3 is connected with one end of the capacitor C3, the other end of the capacitor C3 is connected with the output end of the integrated operational amplifier C3, the other end of the capacitor C9 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C10 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C11 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C12 is connected with the output end of the integrated operational amplifier A3, the output end of the integrated operational amplifier A3 is connected with the input end of the central processing device, and the signal filtering unit transmits the voltage signal V0 to the central processing device.
Preferably, the central processing means will receive an anchoring force FBAnd transmitting the anchoring force F to a comparison module for transmitting the anchoring force FBComparing with anchoring force F, | FB-F ≥500N, the comparison module outputs alarm information to a display, if FB-F I < 500N, the comparing module outputs the qualification information to the display.
Preferably, the temperature sensor is a ceramic-encapsulated platinum resistance temperature sensor.
Preferably, the central processing unit is an 8-bit microprocessor, Atmega 128.
Preferably, the display is an LCD display unit, which is powered with a voltage of 3.3V.
Compared with the prior art, the invention has the following beneficial effects:
(1) the invention provides an outer cantilever anchoring force calibration system, which calibrates the outer cantilever anchoring force of a double-limb thin-wall pier by utilizing a central processing unit, a theoretical value input end, an analysis end, a force sensor, a signal processing circuit, a temperature sensor, a comparison module and a display, compares the outer cantilever anchoring force calculated theoretically with the outer cantilever anchoring force measured by the sensor to know whether the outer cantilever anchoring force test is accurate, and collects temperature information of a test field through the temperature sensor so as to enable a worker to clearly see the field environment temperature during the outer cantilever anchoring force test.
(2) The invention further provides an external cantilever anchoring force calibration system, which is characterized in that a signal-to-noise ratio of signals acquired by a force sensor is not ideal, so that a signal amplification unit is used for amplifying the voltage V0 output by the force sensor through an integrated operational amplifier A1-A2, a capacitor C1-C6, a triode VT1-VT2, a voltage stabilizing tube D1-D2 and a resistor R1-R9, and the signal amplification unit formed by the integrated operational amplifier A1-A2, the capacitor C1-C6, the triode VT1-VT2, the voltage stabilizing tube D1-D2 and the resistor R1-R9 has drift of 0.4 mu V/DEG C, offset within 2 mu V, 100pA bias current and noise within a bandwidth of 0.1Hz to 10Hz and 2.6 nV. The signal filtering unit performs low-pass filtering processing on the amplified voltage signal by using resistors R10-R16, capacitors C7-C12 and an integrated operational amplifier A3, so that the force detection accuracy is improved.
Drawings
FIG. 1 is a schematic diagram of entity load partitioning;
FIG. 2 is a diagram of an outer cantilever end stress model;
FIG. 3 is a functional diagram of the outer cantilever anchoring force calibration system of the present invention;
fig. 4 is a circuit diagram of a signal processing circuit of the present invention.
Reference numerals:
1-a central processing device; 2-theoretical value input end; 3-an analysis end; 4-a force sensor; 5-a signal processing circuit; 6-temperature sensor; 7-a comparison module; 8-display.
Detailed Description
The present invention provides an outer cantilever anchoring force calibration system, which is described in detail below with reference to the accompanying drawings and embodiments.
As shown in fig. 3, the system for calibrating the anchoring force of the outer cantilever provided by the invention comprises a central processing device 1, a theoretical value input end 2, an analysis end 3, a force sensor 4, a signal processing circuit 5, a temperature sensor 6, a comparison module 7 and a display 8.
The output end of the theoretical value input end 2 is connected with the input end of the analysis end 3, the output end of the force sensor 4 is connected with the input end of the signal processing circuit 5, the output end of the analysis end 3, the output end of the signal processing circuit 5 and the output end of the temperature sensor 6 are connected with the input end of the central processing device 1, the input end of the comparison module 7 and the input end of the display 8 are connected with the output end of the central processing device 1, and the output end of the comparison module 7 is connected with the input end of the display 8.
The theoretical value input end 2 is used for inputting parameters for calculating the anchoring force of the outer cantilever under the load, and the analysis end 3 is used for calculating the anchoring force F of the outer cantilever under the load according to the parameters for calculating the anchoring force of the outer cantilever under the load, which are input in the theoretical value input end 2BThe force sensor 4 is arranged at the stress point of the anchoring point and used for detecting the anchoring force signal of the outer cantilever under load, the signal processing circuit 5 is used for processing the anchoring force acquired by the force sensor 4 and processing the processed force signalF to the central processing apparatus 1.
Since the force signal processed by the signal processing circuit 5 is a voltage signal, the central processing unit 1 converts the received voltage signal into a force signal, that is, the voltage signal processed by the signal processing circuit 5 corresponds to the force signal (i.e., satisfies the transfer function relationship of the force sensor 4), and can be simplified as a force signal F.
The temperature sensor 6 is used for detecting the temperature signal of the test site, and the central processing unit 1 receives the anchoring force FBAnd the anchoring force F to a comparison module 7, the comparison module 7 being adapted to transmit the anchoring force FBComparing the anchoring force F with the anchoring force F, transmitting the comparison result to the display 8 for displaying, and the central processing device 1 receiving the anchoring force FBThe anchoring force F and the temperature signal are transmitted to the display 8 for display.
The method comprises the steps of calibrating the anchoring force of an outer cantilever of the double-limb thin-wall pier by utilizing a central processing unit 1, a theoretical value input end 2, an analysis end 3, a force sensor 4, a signal processing circuit 5, a temperature sensor 6, a comparison module 7 and a display 8, comparing the anchoring force of the outer cantilever calculated theoretically with the anchoring force of the outer cantilever measured by the sensor to know whether the anchoring force test of the outer cantilever is accurate or not, and acquiring temperature information of a test site through the temperature sensor so as to enable workers to clearly know the site environment temperature during the anchoring force test of the outer cantilever.
According to the entity load distribution of the 0# block, dividing the 0# block load (including the self weight of the template) into the following parts according to the figure 1: outer cantilever load w 1; the middle load w2 is the load between the double-limb thin-wall piers; pier top load w3, i.e. the load acting directly on the pier stud. The detail of the division is shown in figure 1.
Specifically, the theoretical value input end 2 is used for inputting the parameter for calculating the anchoring force of the outer cantilever under the load as the load of the outer cantilever
The analysis end 3 is used for calculating the anchoring force F of the outer cantilever under the load according to the parameter which is input from the theoretical value input end 2 and used for calculating the anchoring force of the outer cantilever under the loadBThe method comprises the following steps:
and S1, equivalently converting the force: the load of the single-side outer cantilever is shared by 4 groups of brackets, so that the single group of brackets bears the load
In the formula (I), wherein,
representing the load of the single-group outer bracket, and 1.1 is a load safety coefficient;
s2, uniform line load conversion: single-group outer bracket load is converted into uniform distribution line load
In the formula (I), wherein,Lacting length for outer bracket load;
s3, determining a prepressing point, converting the uniform distribution line load into a concentrated load, and determining the position of the prepressing point:
wherein x represents the distance from the prepressing point to the anchoring point;
as shown in fig. 2, x is the length of the segment AB, where point a is the point of applied concentrated force, i.e., the pre-compression point, and point B is the anchor point.
S4, calculating the anchoring force F of the outer cantilever under the load according to the distance x between the pre-pressing point and the anchoring point obtained by the calculationBWherein the fixed point and the prepressing point are respectively arranged at two sides of the anchoring point, the distance between the fixed point and the anchoring point is y, and the analysis end 3 obtains the anchoring force of the outer cantilever under the load
；
As shown in fig. 2, y is the length of BC segment, where point C is a fixed point.
S5, analysis end 3Anchoring force F of outer cantilever under loadBTo the central processing unit 1.
Specifically, the force sensor 4 is arranged at an anchoring point stress point and used for detecting an anchoring force signal of the outer cantilever under a load, and the signal processing circuit 5 sequentially performs signal amplification and signal filtering processing on the anchoring force acquired by the force sensor 4.
As shown in fig. 4, the force sensor 4 is configured to detect an anchoring force signal of the outer cantilever under a load, convert the collected force signal into a voltage signal V0, and transmit the voltage signal V0 to the signal processing circuit 5, wherein V1 is the voltage signal processed by the signal processing circuit 5, the signal processing circuit 5 includes a signal amplifying unit and a signal filtering unit, an output end of the force sensor 4 is connected to an input end of the signal amplifying unit, an output end of the signal amplifying unit is connected to an input end of the signal filtering unit, and an output end of the signal filtering unit is connected to an input end of the central processing unit 1.
Specifically, the signal amplification unit comprises an integrated operational amplifier A1-A2, a capacitor C1-C6, a triode VT1-VT2, a voltage regulator tube D1-D2 and a resistor R1-R9, wherein a first pin of the integrated operational amplifier A1 and a2 is an-IN pin, a second pin of the integrated operational amplifier A1 and the integrated operational amplifier A2 is a + IN pin, a third pin of the integrated operational amplifier A COMP pin is a COMP pin, a fourth pin of the integrated operational amplifier A V + pin, a fifth pin of the integrated operational amplifier A S/D pin, a sixth pin of the integrated operational amplifier A1 and the integrated operational amplifier A2 is a V-IN pin, a seventh pin of the integrated operational amplifier A + IN pin is an OUT pin, and an eighth pin of the integrated operational amplifier A pin is an NC pin.
Wherein, the output end of the force sensor 4 is connected with one end of a resistor R2, one end of a resistor R1 is grounded, the other end of a resistor R1 is connected with one end of a resistor R2, the other end of a resistor R2 is connected with a first pin of an integrated operational amplifier A1, the other end of a resistor R2 is also connected with one end of a resistor R3, a second pin of an integrated operational amplifier A1 is grounded, one end of a capacitor C2 is grounded, the other end of a capacitor C2 is connected with one end of a resistor R4, the other end of a capacitor C2 is also connected with a-15V power supply, a sixth pin of the integrated operational amplifier A1 is connected with a-15V power supply, the other end of a resistor R4 is connected with a third pin of an integrated operational amplifier A1, a fourth pin of the integrated operational amplifier A1 is connected with a +15V power supply, one end of a capacitor C1 is grounded, the other end of a capacitor C1 is connected with a +15V power supply, the other end of a resistor R3 is connected with the other end of a resistor R5, the other end of the resistor R3 is connected with an anode voltage regulator 1, the cathode of a voltage regulator tube D1 is connected with the base of a triode VT1, the cathode of a voltage regulator tube D1 is also connected with one end of a resistor R5, the other end of the resistor R5 is connected with a +30V power supply, the other end of the resistor R5 is also connected with the collector of a triode VT1, the other end of a capacitor C5 is also connected with the emitter of the triode VT1, one end of a capacitor C3 is connected with the cathode of the voltage regulator tube D2, one end of a capacitor C3 is also connected with one end of the capacitor C6, the other end of a capacitor C3 is connected with the fifth pin of the integrated operational amplifier, the anode of the voltage regulator tube D2 is connected with the base of the triode VT2, the anode of the voltage regulator tube D2 is also connected with one end of the resistor R7, the other end of the resistor R7 is connected with a-30V power supply, the other end of the resistor R7 is also connected with the collector of the triode VT2, the other end of the resistor R3 is also connected with the seventh pin of the integrated operational amplifier A1, one end of the capacitor C6 is also connected with the seventh pin of the integrated operational amplifier 1, a seventh pin of the integrated operational amplifier a1 is connected to the 2 nd pin of the integrated operational amplifier a2, the other end of the capacitor C5 is further connected to the fourth pin of the integrated operational amplifier a2, the first pin of the integrated operational amplifier a2 is connected to one end of the resistor R8, the other end of the resistor R8 is grounded, the other end of the capacitor C6 is connected to one end of the resistor R6, the other end of the resistor R6 is connected to the third pin of the integrated operational amplifier a2, one end of the resistor R6 is further connected to an emitter of the transistor VT2, an emitter of the transistor VT2 is connected to the sixth pin of the integrated operational amplifier a2, a collector of the transistor VT2 is connected to a-30V power supply, one end of the capacitor C4 is connected to the fifth pin of the integrated operational amplifier a2, the other end of the capacitor C4 is connected to one end of the resistor R9, the other end of the capacitor C4 is further connected to the seventh pin of the integrated operational amplifier a2, and a 7 of the integrated operational amplifier a2 is connected to the input terminal of the signal filtering unit.
Specifically, the signal filtering unit comprises resistors R10-R16, capacitors C7-C12 and an integrated operational amplifier A3.
Wherein, the output end of the signal amplification unit is connected with one end of a resistor R10, the other end of a resistor R10 is connected with the inverting input end of an integrated operational amplifier A3, the non-inverting input end of the integrated operational amplifier A3 is grounded, the other end of a resistor R10 is also connected with one end of a resistor R11, the other end of a resistor R11 is connected with the output end of an integrated operational amplifier A3, one end of a resistor R12 is connected with one end of a resistor R11, one end of a resistor R13 is connected with one end of a resistor R11, one end of a capacitor C7 is connected with one end of a resistor R11, the other end of a capacitor C7 is connected with the output end of an integrated operational amplifier A3, the other end of a resistor R3 is connected with one end of a capacitor C3, the other end of the resistor R3 is connected with one end of the capacitor C3, the other end of the capacitor C3 is connected with the output end of the integrated operational amplifier C3, the other end of the capacitor C9 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C10 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C11 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C12 is connected with the output end of the integrated operational amplifier A3, the output end of the integrated operational amplifier A3 is connected with the input end of the central processing device 1, and the signal filtering unit transmits the voltage signal V0 to the central processing device 1.
In the above embodiment, the noise of the signal processing circuit 5 is within 2.6nV, the drift is 0.4 μ V/deg.c, the integrated operational amplifiers a1-a2 are all LT1210 low-drift integrated operational amplifiers, and the integrated operational amplifier A3 is a TL072 integrated operational amplifier, and because the dc offset and the drift of the integrated operational amplifier a1 do not affect the overall offset of the circuit, the circuit has extremely low offset and drift.
In the signal amplifying unit, the resistance of the resistor R1 is 60 Ω, the resistance of the resistor R2 is 300 Ω, the resistance of the resistor R3 is 1K Ω, the resistance of the resistor R4 is 6.2K Ω, the resistance of the resistor R5 is 1K Ω, the resistance of the resistor R6 is 6.2K Ω, the resistance of the resistor R7 is 1K Ω, the resistance of the resistor R8 is 1K Ω, the resistance of the resistor R9 is 1K Ω, the capacitance of the capacitor C1 is 1 μ F, the capacitance of the capacitor C2 is 1 μ F, the capacitance of the capacitor C3 is 0.01 μ F, the capacitance of the capacitor C4 is 0.01 μ F, the capacitance of the capacitor C5 is 1 μ F, the capacitance of the capacitor C6 is 1 μ F, the voltage regulators D1-D2 are 15V, and the models of the triodes 1-2 are 2N 3904.
In the signal amplification unit, the signal amplification unit has a full power bandwidth of 13MHz, when the received signal is amplified, the integrated operational amplifier A2 is driven by the integrated operational amplifier A1, the integrated operational amplifier A2 further amplifies the collected signal, and the signal amplification unit is stable in capacitive load, has short-circuit protection and can be thermally turned off in case of overheating.
In the signal filtering unit, the signal filtering unit is a filter of-3 dB/oct, firstly, the center frequency of the signal filtering unit is f0Then define f 04 times, 16 times and 1/4, 1/16 times of the total weight of the whole weight of the whole weight of the whole weight of the whole weight of the whole weight of the steelL=20Hz、fH=20kHz gives:
f0with respect to C10=0.01 μ F, the constant R14 of (a) can be obtained as follows:
4 f0when the constants C11 and R15 are 1/2 of C10 value and 1/2 of R14 value, the frequency is exactly 4 f0。16 f0The constants C12 and R16 were also 1/4 which is 1/4 and R14 of the C10 value. f. of0/4、f0The resistance value of the resistor R12 is 100.6K omega, the resistance value of the resistor R13 is 50.32K omega, the resistance value of the resistor R14 is 25.16K omega, the resistance value of the resistor R15 is 12.58K omega, the resistance value of the resistor R16 is 6.29K omega, the capacitance value of the capacitor C8 is 0.04 muF, the capacitance value of the capacitor C9 is 0.02 muF, the capacitance value of the capacitor C10 is 0.01 muF, the capacitance value of the capacitor C11 is 5000pF, and the capacitance value of the capacitor C12 is 2500 pF.
Wherein, the capacitor C7 is used for response adjustment around 20kHz, and becomes a straight line of-3 dB/oct when the capacitance value of the capacitor C7 is 2200pF, the feedback resistor R11 is set equal to R12, and compensates for the attenuation of the signal filtering unit, and R10= R11/a =22k Ω.
Because the signal-to-noise ratio of the signals collected by the force sensor 4 is not ideal, the signal amplification unit is used for amplifying the voltage V0 output by the force sensor 4 through the integrated operational amplifier A1-A2, the capacitor C1-C6, the triode VT1-VT2, the voltage stabilizing tube D1-D2 and the resistor R1-R9, and the signal amplification unit formed by the integrated operational amplifier A1-A2, the capacitor C1-C6, the triode VT1-VT2, the voltage stabilizing tube D1-D2 and the resistor R1-R9 only has drift of 0.4 muV/DEG C, offset within 2 muV, bias current of 100 muV and noise of 2.6nV within a bandwidth of 0.1Hz to 10 Hz. The signal filtering unit performs low-pass filtering processing on the amplified voltage signal by using resistors R10-R16, capacitors C7-C12 and an integrated operational amplifier A3, so that the force detection accuracy is improved.
Specifically, the central processing apparatus 1 receives the anchoring force FBAnd the anchoring force F to a comparison module 7, the comparison module 7 being adapted to transmit the anchoring force FBComparing with anchoring force F, | FBF I is larger than or equal to 500N, the comparison module 7 outputs alarm information to the display 8, F I is larger than or equal to 500NBF I < 500N, the comparison module 7 outputs the qualification information to the display 8.
Specifically, the temperature sensor 6 is a ceramic package type platinum resistance temperature sensor.
Specifically, the central processing unit 1 is an 8-bit microprocessor Atmega 128.
In consideration of the requirements of cost and processing performance, the central processing unit 1 selects the low-power-consumption 8-bit microprocessor Atmega128, the chip has rich hardware resources and has the advantages of low power consumption, multiple functions, low price, strong performance and the like, the Atmega128 is provided with a 128K-byte Flash memory and a 4K-byte EEPROM memory, data acquired by each sensor is directly stored in the EEPROM memory, an ADC port inside the Atmega128 is provided with 8 channels, the resolution of each channel is 10 bits, the input voltage range is 0-5V, the requirement of data itinerant acquisition monitoring can be met, an AD conversion device is not required to be additionally arranged, the design of a peripheral circuit is simplified, and the cost is reduced.
Specifically, the display 8 is an LCD display unit that is powered with a voltage of 3.3V.
In the above embodiment, the LCD display unit is powered by 3.3V voltage to be level-matched with the I/O port of the microprocessor Atmega128, and the interface between the LCD display unit and the microprocessor Atmega128 is communicated by a serial interface.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (9)
1. The calibration system for the anchoring force of the outer cantilever is characterized by comprising a central processing device (1), a theoretical value input end (2), an analysis end (3), a force sensor (4), a signal processing circuit (5), a temperature sensor (6), a comparison module (7) and a display (8);
the output end of the theoretical value input end (2) is connected with the input end of the analysis end (3), the output end of the force sensor (4) is connected with the input end of the signal processing circuit (5), the output end of the analysis end (3), the output end of the signal processing circuit (5) and the output end of the temperature sensor (6) are all connected with the input end of the central processing device (1), the input end of the comparison module (7) and the input end of the display (8) are all connected with the output end of the central processing device (1), and the output end of the comparison module (7) is connected with the input end of the display (8);
the theoretical value input end (2) is used for inputting parameters for calculating the anchoring force of the outer cantilever under the load, and the analysis end (3) is used for calculating the anchoring force F of the outer cantilever under the load according to the parameters for calculating the anchoring force of the outer cantilever under the load, which are input in the theoretical value input end (2)BThe force sensor (4) is arranged at a stress point of an anchoring point and used for detecting an anchoring force signal of an outer cantilever under a load, the signal processing circuit (5) processes the anchoring force acquired by the force sensor (4) and transmits the processed force signal F to the central processing device (1), the temperature sensor (6) is used for detecting a temperature signal of a test site, and the central processing device (1) receives the anchoring force FBAnd transmitting the anchoring force F to the comparison module (7), the comparison module (7) being adapted to transmit the anchoring force FBComparing the anchoring force F with the anchoring force F, transmitting the comparison result to the display (8) for displaying, and leading the central processing device (1) to receive the comparison resultAnchoring force FBThe anchoring force F and the temperature signal are transmitted to the display (8) for displaying;
the theoretical value input end (2) is used for inputting a parameter for calculating the anchoring force of the outer cantilever under the load, namely the load omega of the outer cantilever1The analysis end (3) is used for calculating the anchoring force F of the outer cantilever under the load according to the parameter which is input into the theoretical value input end (2) and used for calculating the anchoring force of the outer cantilever under the loadBThe method comprises the following steps:
and S1, equivalently converting the force: the load of the single-side outer cantilever is shared by 4 groups of brackets, so that the single group of brackets bears the load
In the formula, ω11Representing the load of the single-group outer bracket, and 1.1 is a load safety coefficient;
s2, uniform line load conversion: single-group outer bracket load is converted into uniform distribution line load
In the formula, L is the load acting length of the outer bracket;
s3, determining a prepressing point, converting the uniform distribution line load into a concentrated load, and determining the position of the prepressing point:
wherein x represents the distance from the prepressing point to the anchoring point;
s4, calculating the anchoring force F of the outer cantilever under the load according to the distance x between the pre-pressing point and the anchoring point obtained by the calculationBWherein the fixed point and the prepressing point are respectively arranged at two sides of the anchoring point, the distance between the fixed point and the anchoring point is y, and the analysis end (3) obtains the anchoring force of the outer cantilever under the load
S5, the analysis end (3) anchors the outer cantilever under load to form anchoring force FBTo the central processing device (1).
2. The external cantilever anchoring force calibration system of claim 1, wherein the force sensor (4) is arranged at an anchoring point stress point for detecting an anchoring force signal of the external cantilever under a load, and the signal processing circuit (5) sequentially performs signal amplification and signal filtering on the anchoring force acquired by the force sensor (4).
3. The outer boom anchoring force calibration system according to claim 1 or 2, wherein the force sensor (4) is used for detecting an anchoring force signal of the outer boom under load, converting the collected force signal into a voltage signal V0, and transmitting the voltage signal V0 to the signal processing circuit (5), V1 is the voltage signal processed by the signal processing circuit (5), the signal processing circuit (5) comprises a signal amplifying unit and a signal filtering unit, the output end of the force sensor (4) is connected with the input end of the signal amplifying unit, the output end of the signal amplifying unit is connected with the input end of the signal filtering unit, and the output end of the signal filtering unit is connected with the input end of the central processing unit (1).
4. The system for calibrating the anchoring force of the outer cantilever according to claim 3, wherein the signal amplification unit comprises an integrated operational amplifier A1-A2, a capacitor C1-C6, a triode VT1-VT2, a voltage regulator tube D1-D2 and a resistor R1-R9, wherein the first pin of the integrated operational amplifier A1 and A2 is an-IN pin, the second pin is a + IN pin, the third pin is a COMP pin, the fourth pin is a V + pin, the fifth pin is an S/D pin, the sixth pin is a V-pin, the seventh pin is an OUT pin, and the eighth pin is an NC pin;
wherein, the output end of the force sensor (4) is connected with one end of a resistor R2, one end of a resistor R1 is grounded, the other end of a resistor R1 is connected with one end of a resistor R2, the other end of a resistor R2 is connected with a first pin of an integrated operational amplifier A1, the other end of a resistor R2 is also connected with one end of a resistor R3, a second pin of the integrated operational amplifier A1 is grounded, one end of a capacitor C2 is grounded, the other end of a capacitor C2 is connected with one end of a resistor R4, the other end of a capacitor C2 is also connected with a-15V power supply, a sixth pin of the integrated operational amplifier A1 is connected with a-15V power supply, the other end of a resistor R4 is connected with a third pin of the integrated operational amplifier A1, a fourth pin of the integrated operational amplifier A1 is connected with a +15V power supply, one end of a capacitor C1 is grounded, the other end of a capacitor C1 is connected with a +15V power supply, the other end of a resistor R3 is connected with the other end of a capacitor C5, and a resistor R3 is also connected with an anode of a stabilivolt tube 1, the cathode of a voltage regulator tube D1 is connected with the base of a triode VT1, the cathode of a voltage regulator tube D1 is also connected with one end of a resistor R5, the other end of the resistor R5 is connected with a +30V power supply, the other end of the resistor R5 is also connected with the collector of a triode VT1, the other end of a capacitor C5 is also connected with the emitter of the triode VT1, one end of a capacitor C3 is connected with the cathode of the voltage regulator tube D2, one end of a capacitor C3 is also connected with one end of the capacitor C6, the other end of a capacitor C3 is connected with the fifth pin of the integrated operational amplifier, the anode of the voltage regulator tube D2 is connected with the base of the triode VT2, the anode of the voltage regulator tube D2 is also connected with one end of the resistor R7, the other end of the resistor R7 is connected with a-30V power supply, the other end of the resistor R7 is also connected with the collector of the triode VT2, the other end of the resistor R3 is also connected with the seventh pin of the integrated operational amplifier A1, one end of the capacitor C6 is also connected with the seventh pin of the integrated operational amplifier 1, a seventh pin of the integrated operational amplifier a1 is connected to the 2 nd pin of the integrated operational amplifier a2, the other end of the capacitor C5 is further connected to a fourth pin of the integrated operational amplifier a2, a first pin of the integrated operational amplifier a2 is connected to one end of the resistor R8, the other end of the resistor R8 is grounded, the other end of the capacitor C6 is connected to one end of the resistor R6, the other end of the resistor R6 is connected to a third pin of the integrated operational amplifier a2, one end of the resistor R6 is further connected to an emitter of the transistor VT2, an emitter of the transistor VT2 is connected to a sixth pin of the integrated operational amplifier a2, a collector of the transistor VT2 is connected to a-30V power supply, one end of the capacitor C4 is connected to a fifth pin of the integrated operational amplifier a2, the other end of the capacitor C4 is connected to one end of the resistor R9, the other end of the capacitor C4 is further connected to a seventh pin of the integrated operational amplifier a2, and a fourth pin of the integrated operational amplifier a2 is connected to the signal filtering unit.
5. The outer cantilever anchor force calibration system of claim 4, wherein the signal filtering unit comprises resistors R10-R16, capacitors C7-C12, and an integrated operational amplifier A3;
wherein, the output end of the signal amplification unit is connected with one end of a resistor R10, the other end of a resistor R10 is connected with the inverting input end of an integrated operational amplifier A3, the non-inverting input end of the integrated operational amplifier A3 is grounded, the other end of a resistor R10 is also connected with one end of a resistor R11, the other end of a resistor R11 is connected with the output end of an integrated operational amplifier A3, one end of a resistor R12 is connected with one end of a resistor R11, one end of a resistor R13 is connected with one end of a resistor R11, one end of a capacitor C7 is connected with one end of a resistor R11, the other end of a capacitor C7 is connected with the output end of an integrated operational amplifier A3, the other end of a resistor R3 is connected with one end of a capacitor C3, the other end of the resistor R3 is connected with one end of the capacitor C3, and the other end of the output end of the capacitor C3 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C9 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C10 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C11 is connected with the output end of the integrated operational amplifier A3, the other end of the capacitor C12 is connected with the output end of the integrated operational amplifier A3, the output end of the integrated operational amplifier A3 is connected with the input end of the central processing device (1), and the signal filtering unit transmits a voltage signal V0 to the central processing device (1).
6. An outer cantilever anchoring force calibration system according to claim 1, wherein the central processing device (1) will receive an anchoring force FBAnd transmitting the anchoring force F to the comparison module (7), the comparison module (7) being adapted to transmit the anchoring force FBComparing with anchoring force F, | FBF I is larger than or equal to 500N, the comparison module (7) outputs alarm information to the display (8), F I is larger than or equal to 500NB-fii < 500N, the comparison module (7) outputting qualifying information to the display (8).
7. An outer cantilever anchorage force calibration system according to claim 1, wherein the temperature sensor (6) is a ceramic encapsulated platinum resistance temperature sensor.
8. An outer cantilever anchor force calibration system according to claim 1, wherein the central processing device (1) is an 8-bit microprocessor Atmega 128.
9. The outer cantilever anchorage force calibration system of claim 1, wherein the display (8) is an LCD display unit, which is powered with a voltage of 3.3V.
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