Some standard content:
National Metrology Verification Regulation of the People's Republic of China.IJG928--1998
Ultrasonic Ranger
Issued on March 19, 1998
Implementation on October 1, 1998
Issued by the State Bureau of Technical Supervision
J.IG928-1994
Verification Regulation
of Ultrasonic Ranger
JJG 928--1998
This verification regulation was approved by the State Bureau of Technical Supervision on March 19, 1998, and came into effect on October 1, 1998. bzxz.net
Responsible unit: Shaanxi Provincial Technical Supervision Bureau
Drafting unit: China Testing Technology Research Institute The drafting unit is responsible for the technical provisions of this regulation and the interpretation of this regulation. The main drafter of this regulation:
Li Maoshan
Kui Jianming
Participating drafter:
Tan Jianguo
JJ Xin 928-1998
(China Testing Technology Research Institute)
(China Testing Technology Research Institute)
(China Testing Technology Research Institute) ）
(Shaanxi Surveying and Mapping Instrument Metrology Center)
Technical requirements
Test items and test conditions
Test methods
Test result processing and test period
JJC928--1998
Establishment of standard test field and test methods
Test calculation example
JJC928—1998
Verification procedure for ultrasonic distance meters
This procedure is applicable to the verification of ultrasonic distance meters that are newly manufactured, in use and after repair. Overview
Ultrasonic rangefinder is a kind of instrument that uses wave velocity to measure distance. It is suitable for measuring distance within 100m in air. The standard uncertainty is: 1.5×10-*L) (L is the measured distance). The instrument is mainly used in construction, mechanical installation, farmland water conservancy, highway transportation, mine tunnels and gardening. According to the characteristics of the ultrasonic wave, the application frequency range of the ultrasonic source is: 40k1z. There are two types of ultrasonic rangefinders:
1) Superwave self-reflection type, which does not require a cooperative target and uses the surface to be measured as a reflector. 2) Superwave remote reflection type, which is a rangefinder that requires a cooperative target. Generally, infrared light is used to control the emission of the cooperative target.
2 Technical requirements
1 Appearance and performance verification
1.1 The shell of the instrument is free of silicon damage and the start switch is positive. 1.2 The optical lens is intact and has no looseness. 1.3 The digital display stroke is smooth and has no flickering. When the receiving or transmitting window is blocked, it should be turned off immediately. 1.4 For the acoustic rangefinder in use and after repair, defects that do not affect the accuracy are allowed. 2 Counting frequency verification
The counting frequency of the ranging position is consistent with the relevant quantity of the sound wave speed (20°): 3 Ultrasonic emission frequency verification
The ultrasonic vibration frequency and the ultrasonic transducer frequency should be known to maintain the best emission frequency. 4 Measurement range
The measurement range of the newly manufactured ultrasonic rangefinder is consistent with the nominal value. The measurement range in use and after repair should not be less than 4/5 of the nominal value.
5 Temperature compensation
The temperature compensation function of the instrument with temperature compensation function should be reliable. 6 Distance measurement application square
Additional tape number (A) and multiplication tape number (K), use no less than four standard distance sections, and calibrate at the calibration site with a standard uncertainty less than 1U-4L, and find A and KD in the following form of distance measurement equation = AIKX
Standard distance:
In the formula: P,
1 = 1,2,, for
Additional tape number;
Multiplication tape number:
X, the quotient value displayed by the distance meter.
Standard deviation of measurement
JJG928—199H
Standard deviation of measurement should not exceed the standard uncertainty. When the instrument moves along the observation line, increasing or decreasing a distance equivalent to a cloud, the instrument display also increases or decreases accordingly.
Range reproducibility
Measurement value is stable and varies within the standard uncertainty range.
Comprehensive distance measurement standard error
Comprehensive distance measurement standard error should be less than the instrument standard uncertainty. III
Verification items and verification conditions
Verification items and main verification tools are listed in Table 1
Applicable items
Computer components
Optical components
Mathematical display
Counting
Emitting frequency
Temperature compensation
Range measurement multiplication factor
Instrument sensitivity
Range measurement reproducibility
Only the verification tools should be verified
Machine Oscilloscope
Frequency meter and oscilloscope
Standard length calibration site
Humidity chamber
Standard high-quality calibration site
Standard long-range calibration site
Calibration site relocation
Registration operation
The number is a mandatory inspection item: “-”, the number is optional: Note: Some items are marked with “+”
Newly made
Repair point
12 Calibration conditions
12.1 Temperature: 10.-30 12.2 Relevant humidity: less than 85%
12.3 Wind speed: less than level 3.
JJG928—1998
12.4 Surrounding environment: no vibration or electrical interference that may affect the test. IV. Test method
13 General performance test of outer skin
H Test the integrity of the outer skin, and check whether there is any looseness inside the device, and check the digital display performance after power on. Test each item listed in Article 1 one by one
14 Counting frequency
Use digital frequency meter to directly Directly measure the counting rate of the distance meter, or indirectly use the known distance as a standard to calibrate the distance meter.
15 Ultrasonic emission frequency
Before the ultrasonic wave passes through the acoustic energy sensor, measure the frequency of the ultrasonic source, use a digital frequency meter and an oscilloscope to observe the signal conversion speed and waveform, as shown in Figure 1, whether it is consistent with the core frequency of the ultrasonic transducer. Oscilloscope
Ultrasonic control instrument
Micrometer
16 Range measurement
The instrument is installed in the standard length of the distance meter. On the field, move the instrument or "target" until the distance measured by the instrument is stable and the displayed value is positive. For the rangefinder after medium maintenance, the ratio of this distance to the nominal measurement is slightly greater than 4/5.
17 Temperature compensation
Place the ultrasonic liquid rangefinder in a temperature chamber of about 5°C, and change the temperature from 10 to 0. The temperature measurement error is less than 1°C. For every change of 5°C, one degree of separation can be achieved, and the measured distance should not change (Figure 2) 18 Distance measurement application equation
As shown in Figure 3: The ultrasonic rangefinder is installed in the standard length calibration field mark ", for the ultrasonic rangefinder The instrument is used for distance measurement value inspection, and the standard length and the distance measurement are displayed (see Appendix 2, Table 1). =1,2,,m
Wu City:
A distance number:
Ultrasonic wave variable
J.IF92R—1998
Secret photo box
A Sun chooses the pier of the inspection site according to the mark; an ultrasonic distance meter display system is:
According to the following calculation, the application force to be measured is the cooperation of the formula
nEDx-(xi(E)
n(7x) -(Ex)4
(n)()-(x)(x)
(Ex)(Zx)
Xie Xinyi
Measurement standard deviation
Cooperation
Length calibration field (static field into fixed position) diagram?
The calibration value is measured with 1% of the test results (see Table 1 in Table 2) and the residual is calculated using the error equation ()AK.XD
Substitute the following formula to calculate the visual standard
1 = 1,2,,
Formula: 5-
Measurement standard deviation:
——Number of equations
For example, see Table 1.
Instrument sensitivity
JJG 928-—19u8
234 -27
As shown in the figure, the mobile workbench is moved along the measuring wall, and the measuring instrument is reliable. The "belt" or reflective screen is left: the workbench is moved forward along the measuring wall line, and the ruler of the moving table is used to obtain the moving distance () at the same time: read the WeChat displayed by the distance measuring device, and measure 5 in the positive and negative directions for each movement. The following formula is used to calculate the standard error of the distance measurement sensitivity
In the formula: s Instrument sensitivity standard error:
4--The difference between the magnetic dynamic value (AD,) of the mobile station and the change in the display value (AX,) of the measuring instrument; \2--The number of measurements
For calculation examples, see Appendix 2 of the record 2:
Ultrasonic distance measuring instrument
Ice grain
Mobile station
21Distance repeatability
Install the ultrasonic distance measuring instrument within the reliable measurement range, repeat the measurement based on a fixed distance, and calculate the distance. After the instrument is installed: re-measure at regular intervals, measure once every 2 minutes, and measure 6 times in total. Use the following formula to calculate the standard deviation of the repeated distance,
55 - / (x, - Xo)-(n1)
Measurement repeatability standard deviation:
Measurement mean:
Each measurement value;
Number of fish caught.
Calculation example distance measurement see Appendix 2 Appendix 3,
22 Comprehensive distance measurement standard error
JJG928—1998
Standard length calibration field standard error and detector standard error world part composed of: Comprehensive measurement standard error (synthetic standard uncertainty! eVi-m
Where: Characteristic-standard length field detection standard error; m2 detected instrument standard error,
m2 = / sf - +
V. Verification result processing and verification cycle
23: The number of vibrations provided by the trend wave rangefinder after verification. 23.1 Coefficients of the distance measurement equation
D, = A +KX
Formula: A Additive constant:
K——Multiplication constant
K—Instrument reading;
D. Actual distance measured by ultrasonic distance meter. 23.2 Actual distance measurement including standard error (synthetic standard uncertainty)\. 23.3 Actual reliable distance measurement.
24 The distance meter that has been calibrated shall be issued with a calibration certificate and provide the data in Article 23: The unqualified one shall be issued with a calibration certificate and explanation.
25 The withdrawal period of ultrasonic distance meter is 1 year.
Appendix 1
928—1
Standard The establishment and test method of the standard calibration site
Standard length calibration site measurement transmission system
The standard length calibration site of the ultrasonic distance meter must meet the length value transmission requirements, as shown in Figure 1.
Standard steel tape measure
2 The establishment method of the fixed pier type standard calibration site Standard length fixed site
Ultrasonic distance meter
Photoelectric distance meter
A small cement patch is made along a straight line upward on the average ground. The end face of the position is about 0.8 from the ground. The underground foundation pool is 100 meters deep underground. The spacing between the center of the disk is 0.1. The cement surface is covered on both sides. The end of the gold shavings fixed mark has a "+" engraved columnar mark. The position should be accurate within 50m, such as 0-5-1015·-20-3060-90 (100) m. Use 4-line
Use the calibrated steel coil to measure the standard length for the site. As a special physical standard for length, it provides the ultrasonic liquid distance meter with a length value transfer standard. 2.1 The same positioning conditions should be met
2.1,1 The length value is accurate. Use a higher-level measuring tool or instrument to measure the length. The standard uncertainty is less than 1×10- (L is the length). Measure twice every noon
2.1.2 The buried position is stable, with good geographical and geological conditions, and can be preserved for a long time. 2.1.3 Pier position planning is shown in Figure 2,
3 Method for establishing a movable bracket standard length calibration field: The movable calibration field is a detection device that can be assembled at any time. Its characteristics all rely on the stability of the pool foundation as a basis for transferring length measurements. Instead, it is assembled before the calibration of the acoustic liquid rangefinder. The measuring device is measured with a standard ruler and the mark is left: after use, the device can be removed. 3.1 The constraints (limit differences) applied during the measurement procedure are shown in Figure 3. 3.2 The movable bracket detection device is shown in Figure 4, with three brackets supporting the Du-shaped mark. 7
JI 928—
Fixed filling position calibration area
Attached figure 2
Front-mounted length adjustment
Ultrasonic control
High training process wood sea
Avoided figure 3
Distance meter early
Infrared light
Taosheng was
Standard tape measure
Attached lake 42 The movable bracket detection device is shown in Figure 4, with three frames supporting the Du-shaped mark. 7
JI 928—
Fixed filling position calibration area
Attached Figure 2
Front-mounted length adjustment
Ultrasonic control
High training process wood sea
Avoid Figure 3
Distance meter early
Infrared light
Taosheng was
Standard tape measure
Attached Lake 42 The movable bracket detection device is shown in Figure 4, with three frames supporting the Du-shaped mark. 7
JI 928—
Fixed filling position calibration area
Attached Figure 2
Front-mounted length adjustment
Ultrasonic control
High training process wood sea
Avoid Figure 3
Distance meter early
Infrared light
Taosheng was
Standard tape measure
Attached Lake 4
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