SU822037A1 - Correlation speed meter - Google Patents

Description

The invention relates to contactless measuring instruments for motion parameters of an object using random fluctuations in illumination, reflected or emitted by a controlled surface, and can be used in the rolling industry, aviation, transportation, etc. A contactless correlation device is known for measuring the path and linear velocity of an object. 1 However, this device is difficult and the measurement results; The results obtained at its output contain a quantization error due to the presence of a discrete counter element of a number proportional to the distance traveled, which reduces the measurement accuracy. The closest to the proposed device is a device containing transducers, amplifiers, multiplying links, integrators, a subtracting link and an adjustable delay unit made on a frequency controlled oscillator, the input of which is connected to the output of the subtracting link, and the output is connected to a pulse distributor three buses, one of which is electrically connected to the keys. The signal passes the first transducer to the storage capacitance connected to the emitter follower, and the second and third tires are connected to the keys skip and the signal output from the emitter follower to the inputs of multiplying units whose outputs are keys via the bus distributor are connected to the inputs of integrator 12. However, with this device can not measure the negative rate of movement of the controlled object. The purpose of the invention is to extend the functionality of a device using a correlation method for measuring the speed of movement of a monitored object. The goal is achieved by the fact that, in a known correlation measuring instrument for the velocity of an object, containing two photoelectric converters, two amplifiers connected to converters, two multiplication units connected in series with the integrators, a comparison unit whose two inputs are connected to the outputs of two integrators, an adjustable lag unit, two AND circuits, a speed indication unit, with the output of the first amplifier

connected to the first input of the first multiplication unit; a directional indication unit, an OR circuit, a second adjustable delay unit, two tracking circuits connecting the integrator outputs to the control inputs of the corresponding adjustable delay unit, and the first amplifier through the second adjustable delay unit are entered. associated with the first input of the second multiplication unit, and the output of the second amplifier through the first adjustable delay unit with the second input of the first multiplication unit and with the second input of the second multiplication unit The inputs of the first AND circuit are associated with the information output of the first adjustable delay unit and the first output of the comparison unit, and the inputs of the second AND circuit are connected with the information output of the second adjustable delay unit and the second output of the comparator unit, the outputs of the two AND schemes through the OR circuit with the speed indicating unit, and in addition, both outputs of the comparison unit are associated with the direction indication unit. The drawing shows a functional diagram of a correlation meter measuring the speed of an object

The proposed device contains two photoelectric converters 2 and 3, two amplifiers 4 and 5, two blocks 6 and 7 of adjustable delay, two blocks 8, 9 multiplication, two integrators 10 and 11, two tracking circuits 12 and 13, block 14. comparison, two the circuits AND 15 and 16, the OR circuit 17, the speed indication unit 18 and the object direction indication unit 19.

The device works as follows.

When the monitored object moves in the direction ,, indicated by an arrow in the drawing, there is an electrical signal f (t) at the output of the photoreceiver 2, and a signal Ht-t exists at the output of the photoreceiver 3; if the object moves in the opposite direction, then signal f (t), and at the output of the photodetector 2 signal f (tT). The time lag of the signal t is defined as:

L,

where L is the base distance between

photodetectors, V - linear speed of movement

object.

When the object is moved in the direction indicated by the arrow in the drawing, the signal f (t) from the photodetector output is fed to the input of the adjustable-delay unit b, where it is delayed by the delay time. The signal from the photodetector 3 is fed to the multiplication unit 8, where the product of the delayed signal from the photodetector 2 and the signal from the photodetector 3 is formed. The product is fed to the integrator 10, the output of which is the mutual correlation function of the signals R (g). The maximum of this function will exist at. Zid - The tracking scheme monitors the maximum of K (s), supporting Sao, D. At the output, the integrator 11 will also have a mutually correlation function R :, (&), however, the maximum value of R (5) is significantly less than the maximum). When the object moves in the opposite direction, on the contrary, the maximum value of R (€) is significantly less than the maximum of Rg. (C). The signals R (f) and 2.) are supplied to comparison unit 14. If R (t)), then the signal appears at the first output of block 14, opening the circuit 15, if R (P) Ku (And then the signal appears at the second output of block 14, opening the circuit 16. Thus, The direction of movement of the object being monitored is determined by the output of the comparison block 14. There is a signal. The outputs of block 14 are connected to the inputs of the direction of movement indicator. Object 19 The signals at the output of the comparison block 14 control AND 15 and 16 so that the output of the circuit OR 17 there is a signal and taken from the information output of the corresponding block. According to the value of the time delay, with a known value of /, the speed of the object V is determined, therefore the T signal from the output of the OR circuit 17 is fed to the speed indication unit. The proposed device allows determining the direction of movement of the object being monitored and measuring the magnitude of the speed of movement when moving an object both in the forward and in the opposite direction.

Claims (2)

Invention Formula A correlation velocity meter, containing two photoelectric converters, two amplifiers connected to the converters, two multiplication units connected in series with the integrators, a comparison unit, two co-connectors connected to the outputs of the two integrators, an adjustable-delay unit, two circuits And, a speed indication unit, wherein the output of the first amplifier is connected with the first input of the first multiplication unit, characterized in that, in order to expand the functional possibilities by determining the direction of the first An additional OR scheme is introduced into it, the second block of adjustable delay. a direction indicating unit, two tracking circuits linking the integrator outputs to the control inputs of the respective adjustable delay blocks, the output of the first amplifier through the second adjustable delay block being connected to the first input of the second multiplication unit, and the output of the second amplifier through the first adjustable delay block zan with the second entrance the first transfer unit and with the second input of the second multiplication unit, the inputs of the first circuit. Both are associated with the information output of the first variable lag unit and the first the output of the comparator, and the inputs of the second circuit AND of the connection with the information output of the second block of the adjustable delay and the second output of the comparison block, the outputs of the two circuits AND through the OR circuit are connected with the input index, and, moreover, both outputs of the block comparisons are associated with a directional display unit. Sources of information / taken into account in the examination , 1. USSR author's certificate No. 402803, cl. G 01 P 3/68, 1973. 2. USSR author's certificate W253462, cl. G 01 P 3/54, 1971 (prototype).