SU1185081A1 - Remote-control meter of the thickness of oil film - Google Patents

Abstract

REMOTE OIL FILM THICKNESS MEASURER containing a source of monochromatic optical beam, a beam splitter optically coupled to the source and intended to divide the light beam into two, a scanning element placed along the second light beam, the first and second photodetectors located respectively along the reflected from the investigated film of the first and second light rays, and the signal processing system, to the first and second inputs of which are connected the corresponding photodetectors, which differ So that, in order to ensure accuracy and speed of measurements. The signal processing system is made in the form of a comparison device, a block of maxima and minima extraction, an angle-voltage converter, an electronic key, a function converter, a quantizing unit and an averager; the angle-voltage converter output is connected via an electronic key to the first input of the function converter, control The electronic key input and the second input of the function converter are connected to the output of the comparator, and the output of the function converter is connected to the first the input of the quantization unit, the second and third inputs of which are connected respectively to the first and second outputs of the maximums and minimums allocation unit, the output of the quantizing unit is connected to the input of the averager, the input of the maximums and minimums selection unit and the input of the comparison device are respectively the first and second inputs of the processing system signal, the scanning element is connected to the input of the angle-voltage converter, which is the third input of the signal processing system.

Description

The invention relates to a measurement technique, in particular, to those for measuring a crowd of thin films and can be used, for example, in aircraft and ship automatic means of express control of oil pollution in water bodies. The purpose of the invention is to increase the accuracy and speed of measurements of oil film thickness. FIG. Figure 1 shows the block diagram of the Remote meter of oil film tol1TSIN; in fig. 2 time diagrams of changes in film thickness along the path of movement of the carrier and signals at the inputs of the processing system, as well as the calibration dependence of the limiting angle on the film thickness in FIG. 3 - switching characteristics (dependence of stepwise varying voltage on current values of film thickness). The remote oil film thickness meter contains a source 1 of a monochromatic optical beam, a beam splitter 2, a scanning element 3, the first 4 and 5 photodetectors, the outputs of which are connected to the first and second inputs of the processing system 6, and the third input of the processing system 6 is connected to the scanning element 3, wherein the processing system 6 comprises a max-and a mini-allocation unit 7, a comparison device 8, an angle-to-voltage converter 9, an electronic key 10, a functional converter 11, a quantization unit 12 and an averager 13, output which is the output system 6 in particular. signal bots. The output of the converter 9 via the electronic key 10 is connected to the first input of the functional converter 11, the control input. The electronic key 10 and the second input of the functional converter 11 are connected to the output of the comparator device 8, the output of the functional converter 11 is connected to the first input of the quantization unit 12, the second and third inputs of which are connected respectively to the first and second outputs of the maximum and minimum isolating unit 7. The output of the quantization unit 12 is connected to the input of the averager 13, the input of the maximum and minimum separation unit 7 and the input of the comparison device 8 are the first and second inputs of the processing system 6. the scanning element 3 is connected to the input of the converter 9, which is the third input of the processing system 6. Remote meter thickness of the oil film on the surface of reservoirs works as follows. In the initial state, the remote meter is mounted on board the carrier (vessel, helicopter, aircraft), the optical beam of the source 1 (for example, a laser) is directed to the beam splitter 2, which divides the optical beam into two beams. The first beam is directed vertically (or at a small angle to the vertical) to the water surface under investigation, and the second beam is scanned by the scanning element 3 at different angles to the water surface in a plane perpendicular to the direction of movement of the carrier. Then, the carrier with a remote meter on board begins to move in the direction of the propagation of wind waves, and the photodetectors 4 and 5 are spatially oriented to receive reflected first and second rays, whose intensities in photodetectors 4 and 5 are converted into electrical signals and fed to the first and second inputs of the system 6 processing. Let the thickness of the film along the path of movement of the carrier be changed according to the law shown in Fig. 2 a (dependence when moving from the periphery to the center of the oil spot). During the measurement process, the maximum V and minimum V. values of the signal from the output of the first photodetector 4 (Fig. 25) are sequentially fixed in time, and the voltage V of the signal from the output of the second photodetector 5 (Fig. 2g) is compared in device 8 compared to a given comparison threshold Vp, for example, equal to OP m V where Vj is the maximum signal value of the second photodetector 5. When the current value of V becomes equal to the comparison threshold V, in the comparison device 8 a command pulse is generated to the control inputs of the key 10 and functionally of the transducer 11. After otkrytsh key 10 output from the transducer 9, an angle-voltage voltage Vj, corresponding op3.

the scan angle oi determined at this point in time t (Fig. 2c) is fed to the information input of the functional converter 11 in which the dependence h f (oL) is stored, where h is the film thickness (fig. 2-). This signal V, proportional to oLf, permits the comparison of the value of h | to the output memory cell of the functional converter 11 until the next time instant t 1 of the operation of the comparison device 8. Value h | supplied from the output of the functional converter 11 to the information input of the quantization unit 12, in which it is compared with predetermined quantized levels h 1dB of the switching characteristic Ket f (hK,) (Fig. 4c, S), and, depending on the control signal The change in the type of switching characteristic (for minima - Fig. 3 ", for maxima - Fig. 25), i.e., is formed automatically in block 7 of the selection of maxima and minima on its first or second outputs. the signals from the outputs of block 7 are control for block 12 quantization.

UNIT 12 quantization works as follows. When blocking in block 7 the extremum of the signal of the first photodetector 4, the corresponding control pulse arrives at the first or second trigger inputs of block 12 (not shown), sets the trigger, sets two switches (not shown) to the corresponding position, thereby shifting up and down , for the minima of Fig. 4o (), the switching characteristic is quantized, and a counter (not shown) through the control input O is then set to the zero state. Then a triggering occurs, another trigger opens the key (not cauldron) through which the counting of the counter is input sequence counter clock frequency

850814

counts the number of pulses, and the decoder at its output accordingly converts them into a KOMMyTatopoM control signal (not shown). 5 The output of the switch is a step voltage h, given by a resistive divider. Each quantum of step voltage is set by series-connected resistors, moreover, the resistive divider is polled with a resistor defining the maximum level of step voltage (Fig. 3). Stepwise varying voltage h is applied to the first input of the comparison circuit (not shown), to the second input of which voltage h hc + dK / 2, formed in the adder (not shown), the maximum value of the step voltage is set at the beginning of the measurements, a lb is L / 2n, where A is the wavelength of the monochromatic optical source, n is the pre-g indicator

25 oil refill, determined from reference data.

At the moment of performing the hp ratio (hc + 4h / 2), the comparison circuit is triggered, and the control pulse from its output overturns the second trigger, the output potential of which is a signal for stopping the operation of the entire unit 12

5 quantization. This also opens the key of the block 12, the output of which receives the quattered value h., Formed from the step voltage Kp at the time of actuation

0 comparison circuits. The resulting series of quantized values of h is fed to the input of average, and a; strand 13, in which they are averaged. The result of the averaged formed

5 p yes quantized values

m

one

- N

is the value of the oil film thickness in the measured oil spot on the water surface.

g 3 5 6 7

Phie. 3

Claims (1)

REMOTE OIL FILM THICKNESS MEASURER, containing a monochromatic optical beam source, a beam splitter optically coupled to the source and intended for dividing the light beam into two, a scanning element located along the second light beam, the first and second photodetectors located respectively along the path reflected from the test film the first and second light beams, and a signal processing system, to the first and second input of which the corresponding photodetectors are connected, characterized in that oh, in order to improve the accuracy and speed of measurements, the signal processing system is made in the form of a comparison device, a unit for extracting highs and lows, an angle-voltage converter, an electronic key, a functional converter, a quantization block and an averager, the output of the angle-voltage converter is through an electronic key connected to the first input of the functional converter, the control input of the electronic key and the second input of the functional converter are connected to the output of the comparison device, and the output a national converter is connected to the first input of the quantization block, the second and third inputs of which are connected respectively to the first and second outputs of the maximum and minimum block, the output of the quantization block is connected to the averager input, the input of the maximum and minimum block and the input of the comparison device are respectively the first and second inputs of the signal processing system, the scanning element is connected to the input of the angle-voltage converter, which is the third input of the signal processing system. IWgTT'TTS