SU1254411A2 - Device for photographing models moving with high speed - Google Patents

Abstract

The invention relates to a measurement technique and makes it possible to increase the measurement efficiency. When the model crosses the plane of the sensor 1 to the reversible counter (PC) 7 and to the reversing time-impulse transducer (VIP) 9, inputs 14, 16 receive a pulse, initiating a direct conversion. When the model crosses the plane of sensor 2 to PC 7 and to VIP 9, inputs 17 and 19 receive a pulse initiating an inverse transformation. When the model crosses the plane of the sensor 3 to PC 7 and VIP 9, inputs 20, 21 receive a pulse, stopping the arrival of clock pulses on them. From sensor 3 to VIP 8, input 18 receives a pulse initiating the inverse transformation, and simultaneously inputs 28 and 29 from sensor 3 receive a signal to comparison circuits 10 and 11 of the comparison resolution. At the moment of coincidence of the VIP 8n counter 7, the comparison circuit 10 at input 30 generates a pulse to start the lamp of the pulsed radiation source 5, and its gate is controlled by a pulse from the comparison circuit .11 at input 31. The device allows to measure the flight time in the whole test range of speeds and accelerations. Invention - additional to auth. St. No. 1174888. 1 Il. B (L

Description

is located at a distance f behind the sensor 3.

The key register 6 can be made on multi-position push-button switches of the type MPK-2. Reversible counter 7 and time-to-pulse converters 8 and 9 and digital circuits 10 and 11 comparisons can be implemented on counters, logic elements and triggers of integrated circuits of average speed, for example, on 155 or 133 series. The frequency of the master pulse generator is chosen to be 10 MHz.

The device works as follows

The invention relates to a measurement technique and can be used to automate physical experiments in research systems for moving objects.

The purpose of the invention is to increase the efficiency of the changes.

The drawing shows a block diagram of the device.

The device contains three sensors 1-3 positions of moving models, a camera 4, a pulsed radiation source 5, a key register 6, a reversible counter 7, two reversing time-pulse converters 8 and 9, two digital cxej i 10 and 11 comparisons, bus 12 initial Settings, 13 Key Register Output, Inputs

14–16 forward transforms, inputs by acceleration a, 17–19 reverse transforms, 20 volts V inputs at time t, determine 20 and 21 transform stops, enter as V at + U / / (where, U - - beginning15

all at once ..

With a linear change in the velocity of the model in the area f, + f ,, + f c, the value is the speed of the speed), and time t;

22 entries into the counter, inputs 23 and 24, zeroing, inputs 25-27 clock pulses, inputs 28 and 29 enabling operation of the comparison circuits 10 and 11, output 30 controlling a pulsed radiation source 5, output 31 controlling a gate (not shown) of a pulse sensor

five., , ; , - .. -.

The sensor outputs 1-3 of the position of the moving model are connected to the corresponding inputs 14-21 of the reversible counter 7 and the time-pulse converters 8 and 9 to the inputs 28 and 29 of the comparison circuits 10 and 11, the outputs of the key register 6 are connected to the first group of inputs of the counter 7 the output of which is connected to the first group of inputs of the first comparison circuit 9, the other bit inputs of which are connected to the outputs of the bits of the first converter 8 and the first group of inputs of the second comparison circuit 1.1, the other bit inputs of which are connected to the output; orogo transducer 9, the output 30 of the first comparing circuit 10 is connected to the control input of the pulsed source 5, and comparing the output 31 of the second circuit 11 is connected to the gate control input of a pulsed source Chogo 5.

The sensors 1-3 of the position of the moving model are located along the motion path at distances of 1 and Ig. Before starting the experiment, the response delay of the pulsed radiation source i is determined, and the time from the supply of the control pulse to the start of the radiator lamp to the moment of the start of the actual radiation, i.e. the pumping time, after which photographing can be made. impulses) direct and reverse transform T

Etc

different express imeSSI

A typing system containing the basic n units and in the two-chamber 4 with an open shutter during the whole time of the experiment and the pulsed source 5 is installed on the keyboard: the register. In the main device, the control pulse triggering

254411 2

is located at a distance f behind the sensor 3.

The key register 6 can be made on multi-position push-button switches of the type MPK-2. Reversible counter 7 and time-to-pulse converters 8 and 9 and digital circuits 10 and 11 comparisons can be implemented on counters, logic elements and triggers of integrated circuits of average speed, for example, on 155 or 133 series. The frequency of the master pulse generator is chosen to be 10 MHz.

The device works as follows

15

this acceleration a, growth V at time t is defined as V at + U "/ (where, U" is the beginning of time.

With a linear change in the velocity of the model in the area f, + f ,, + f with the value of the catastrophic acceleration a, the growth rate V at the moment of time t is defined as V at + U „/ (where, U„ is the initial - - zero value speeds), and time t;

span areas f ,, 2 and f, can be described by the following expression:

i;

26;

141

0

five

where Vj, V, -, are the velocity values at the boundaries of the section.

If, 2,, i-i t, -f At, and + 4t2, you can report that the transit times of neighboring sections. differ at the same time, i.e. Ai, liii. So

5, by determining the time difference At, the span of sections B, and E, and increasing (decreasing) the time of flight tj by this difference, you can set the time t tj + iiy of the span by the model

0. Photographic section, in which a pulse is generated at the output 20 for controlling the gate of the radiation source. I. -. :

Before the start of the experiment, the response delay of the pulsed radiation source i is determined, and A is the time from the delivery of the control pulse to the start of the lamp of the radiator until the start of the radiation itself, i.e. the pump time, after which photographing can be taken. ) direct and reverse conversion

different express change

n units „„ and in binary code set on the keyboard: register. In the main device, the control pulse triggering

pulsed radiation source occurs at exit 19 after time i, „„ relative to the moment when the model crosses the third sensor t

- i

ZDp

g,

In the proposed device

the generation of a control pulse at output 19 takes place after a time зд i i ad t, j - 4g, - t cd,.

Before the start of the experiment, when a pulse is applied through the initial setup bus 12, a binary code 1inz, specified on the key register 6, is set to the reversible counter 7, and the time-to-pulse converters 8 and 9 are set to the zero state.

When the model crosses the plane of the sensor 1 to the reversible counter 7 and the reversing time-impulse transducer 9 through the inputs 14 and 16 pr -20 m -pulse transducers 8 and 9

In this case, the pulse is transmitted, initiating a direct transformation, so that the clock pulses with a period arrive at the inputs of the forward count.

When the model 25 crosses the sensor 2 to the reversible counter 7 and the reversible time-pulse converter 9, inputs 17 and 19: the inverse transformation receives a pulse that initiates the inverse pre-Q formation. At this point in the converter 9 a binary code is formed, which characterizes the time t, the span of the section 6j, and in the counter 7 - the binary code, which characterizes the 1st time t, + t zdl. Then the clock pulses with a period

35

 arrive at the inputs of the countdown. Simultaneously from sensor 2 to reversing time-pulse conversion

The transducer 8 enters at input 15 a direct conversion, a pulse that initiates its direct conversion.

When the model crosses the plane of the sensor 3, the counter 7 and the converter 9 through the inputs 20 and 21 of the I transform stop receive a pulse stopping the receipt of clock pulses on them.

At this point in time, a code has been generated in converter 9, which characterizes the difference ui, i. - i transit time of sections E, and E and in counter 7 - code t, + t .. At the same time, from sensor 3 to converter 8 on input 1B, the inverse transform-55 of the next section does not exceed

the impulse arrives, initiating its inverse transformation. By the moment in the converter 8

l

generated a binary code characterizing the time -1 of the span of section P ,. In addition, from the sensor 3, inputs 28 and 29 to the comparison circuits 10 and 11 receive a comparison resolution signal. Next, the clock pulses with a period

T „p arrive at the input of the inverse of the inverter 8.

At the time of the coincidence of the states of the time-pulse converter 8 and the counter 7, the comparison circuit 10 at the output 30 generates a pulse to start the lamp of the pulsed radiation source 5. This pulse produces through time t p relative to the intersection of sensor 3 and the pumping process of source 5 begins, but the model remains before the section under study

At the moment of coincidence of the states

(when counting down converter 8), the comparison circuit 11 on the output 31 produces a pulse controlling the gate of the pulsed radiation source 5. If the difference At of the time of flight for pairs of adjacent sections C, j is constant, at this moment in the converter 8 a code is formed that characterizes the time t At of the section span. Thus, at the moment, the model is located in the section under study, i.e., the model is illuminated with a radiation pulse — photographing itself. When conducting experiments, it is necessary to choose the dimensions of the sections, 6j such that the time of flight i, taking into account the difference ui, the time of flight, is sufficient for pumping the lamp of the radiator (t, d 1 ms). In addition, it is necessary to take into account that when moving models with negative acceleration (deceleration), when counting back, converters 8 and 9 will pass through the zero state, therefore the size of converters must be chosen so that it is possible to measure the time of flight in the entire velocity range and accelerations.

When using a pulse generator frequency of 10 MHz, a model speed of 400 m / s, deceleration acceleration of -1.6 x X 10 m / s, the model deviates from IS0, 3 mm, and the error in determining the source starting time is reduced by 25 MKS. At the same time, when the constant nS 1254A11 "

In terms of the model’s speed, deviation of reference No. 1174888, which is different, is that, in order to improve the accuracy

As a pulse source of measurements, a reversed radiation is introduced into it; a laser counter can be used, installed between the bit source, x-ray sources of the key register and radiation, and any other ones required by the corresponding discharge inputs of two control pulses : one is the main comparison circuit, with the start-up control of the lamp starting, the other the third and fourth inputs of the reverse — to control the shutter of the source counter, 10 respectively are connected to the outputs sensor first and second sensors

Claims (1)

The invention of the position, fifth and sixth positions of the reversible counter are connected to a corresponding device for photographing. Correspondingly, with the bus, the initial set-up speed of the models according to the aut. St. 15 ki and clock input.