SU1080154A1 - Device for automatic rescaling in analog computer - Google Patents

Description

The invention relates to computing, in particular, analog computing machines (LVM).

Devices for automatic zooming are known, comprising electromechanical units that smoothly change the scale of machine variable ij.

The disadvantage of these devices is that (low bandwidth and the need for high-precision synchronization of all devices, especially for this scale, otherwise the solution introduces significant errors that significantly distort the shape of the simulated process,

The closest in technical essence to the proposed is a device for automatic scaling, containing serially connected fixing unit rpa range, block prohibiting a false pulse and a reversible pulse counter, block fixing the sign of the machine variable, connected to the reference voltage sources , connected to the output of the reversible counter, the switching unit of the resistor connected at the input of the operational amplifier and in its feedback circuit. This device performs a stepwise zoom on the output variable of the AVM adder.

The essence of stepwise zooming is to split the entire dynamic range of the physical variable change into a number of contiguous sub-bands, which correspond to the split ranges of the machine variable. For sub-ranges of a machine variable, the sub-band expansion ratio is selected, which is the ratio of the maximum value of the Mass variable (usually this value equal to the maximum voltage of the ABM scale) to the minimum for this sub-range, chosen from the condition of ensuring the quality of the machine solution. These values are subrange boundaries. The product of the expansion coefficients of all subranges of the machine variable must be equal to the dynamic range of change of the physical variable. When the expansion coefficients of the subranges are equal, the maximum values of the physical variable form a geometric progression with a variable equal to the expansion coefficient. Each subrange of the partitioning of the main variable is characterized by the chosen scales of the variable, and consequently, the corresponding transfer coefficients of the adder for each input. The transition of the machine variable to the adjacent subrange leads to a change in the scale of the output variable, which requires a simultaneous change in the transmission coefficients for all inputs simultaneously 2j.

The disadvantage of this device is the limitation of the possibilities in reproducing the operation of summation due to the lack of communication with other similar devices that change the scales of the variables functionally associated with this variable. This circumstance plays an essential role in modeling systems of differential equations with complex crosslinks and functional dependencies. In addition, the absence of a mobile exhibition of different values of the transmission coefficients for the inputs, as well as the complexity of the input resistor switching unit, limits the capacity of the adder and its application for modeling complex systems where it is necessary to sum a large number of variables that vary over significant ranges that overlap the possibilities subbands) of the device. The purpose of the invention: - the expansion of the dynamic range, improving the accuracy and speed of the device.

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To achieve this goal, a device for automatic scaling in an analog computer, containing an operational amplifier, the input of which is connected to the first terminals of the input scale resistors and, through a feedback large-scale resistor, to the output of the operational amplifier, which is the output of the device and connected to the input of the block fixing the boundaries of subranges, the output of which is connected to the input of the block of the prohibition of a false pulse, a reversible counter and switching blocks of resistors whose outputs are connected The interface block, the decoder, the storage unit and the digital-controlled resistance connected between the device inputs and the second terminals of the input scale resistors and the control inputs connected to the outputs of the memory block, the inputs to the inputs of the control inputs of the input scale resistors and the feedback scale resistor are entered. which is connected to the group of outputs of the decoder, the interface unit is connected between the output of the block of the prohibition of a false pulse and the input of the reversible counter, the output of which is connected to the input of the desh a flipper whose zero output is connected to the inhibiting input of the spurious pulse inhibiting unit, and the first and second outputs are connected respectively to the inputs of the switching blocks of the input scale resistors and the switching block of the scale feedback resistor.

Fig. 1 shows a general block diagram of a device for automatically changing the scales of the AVM adder / Fig. 2 is a diagram of blocks for fixing the boundaries of subranges, prohibiting a spurious pulse, conjugation;

The device for automatic scaling in the AVM contains an operational amplifier 1, a block 2 for fixing the boundaries of subbands, connected in series with a block 3 of a false pulse prohibitor, the output of which is connected with through the block 4 of conjugation. reversible counter 5, the outputs of the reversible counter 5 are connected to the inputs of the decoder 6, which is connected to the switching units 7 of the input scale resistors and the feedback feedback resistor 8, as well as to the inputs of the storage unit 9, the outputs of which are connected to the digital-controlled resistors 10 connected to the inputs of the input scale resistors 8.

The unit 2 for fixing the boundaries of subranges (Fig. 2) contains four comparison circuits, on one of the inputs of which the machine voltage y is connected. All comparison circuits form a pulse at the output when the machine variable crosses the subband boundaries, while the first comparison circuit 11 fixes the intersection of the machine variable air boundary (VG) of the + E subband (as - “- E, the linear area of the AVm computing blocks is selected) hell, for example, 100 V for lamp or 50 V, or 10 V for semiconductor AVMs), the second comparison circuit 112 Fixes the intersection of the lower limit of the Bcc subrange whose voltage is chosen from the condition of ensuring the quality of the machine solution, The comparison circuit 11 fixes the intersection of the machine variable negative voltage of the upper limit -Ecg, equal in modulus, the fourth comparison circuit 11 fixes the intersection of the machine variable negative voltage of the lower boundary -E (-, equal to the modulus E gr. Block 3 (FIG. 2) contains two logical elements OR 12 and 13, four one-shot 14-17 with the prohibition of the logical element OR 18 and the logical element AND 19. This block selects the pulses of the block 2 for fixing the boundaries of the subbands, since t is equal to any of the boundaries; um transfer of machine variable Y to the corresponding opposite boundary / while the impulse from it is not

wives to go to the reverse pulse counter 5.

Block 4 of the conjugation (FIG. 2) contains two multi-input logic elements OR 20 and 21, for the first

the inputs of which are connected respectively to the outputs of the single vibrators 14, 16 and 15, 17, and to the other inputs - the outputs of the decoders of other devices of automatic scaling. The outputs of the logic elements OR 20 and 21, which form the busbar for transmitting the signals of addition and subtraction, are connected to the corresponding inputs of the reversible pulse counter 5.

The resistor switching unit 7 (Fig. 2) contains the key elements 22, the control inputs of which are connected to the outputs of the decoder 6 through the matching elements 23,

and the executive parts thereof (e.g., relay contacts) are connected in parallel to sections of large-scale feedback resistors 8 and sections of input large-scale resistors 8 of the operating room.

amplifier 1.

The memory unit 9 is a memory device made, for example, in registers of static triggers. The output of each register is connected to the corresponding digital-controlled resistance of 10, and the inputs of the registers are connected to the corresponding, (1 to the outputs of the decoder, where P is the number of outputs of the decoders for both positive subband numbers and negative numbers, k is the number of outputs of the decoders, to which the key elements are connected, both for positive and for

negative subband numbers.

In fig and 2. The following notation is used:

y is the output of the machine variable, H. Dp is the input machine variables.

 The device works as follows.

Let the output of the operational amplifier 1 (Fig. 1) change the machine variable as shown in. &Amp; 4, i.e. is variable

increases and at the beginning sequentially moves from the zero subband to the first, from the first to the second. in the third one, and then begins to decrease, the same subbands pass in succession in reverse order and, having passed the zero subband, goes to the negative subbands: first, second, then first and. null. Such dvkzhenie peregynoj on subranges we present as 0-1-2-3-2-1-0-1-2-1 -0.

Consider the first transition 0-1. Comparison scheme 1.1 of block 2 with ficsin subrange boundaries produces

impulse at the moment of comparing machine sand with voltage -n-t gp. This pulse is fed to the trigger input of the one-shot 14 block 3 block lazh pulse. The output of the one-shot 14 signal is fed from one side to the input of the logic element OR 12, and its output to the bar, the input of the one-shot 15 and, thus, CctMBM blocks its operation at the transition time of the machine variable Y from VG to NG, because upon reaching NG the comparison circuit tl2 produces a pulse which with this change of variable is false. Due to such blocking, the pulse from the comparison circuit llj does not pass to the input of the logical element OR 21. On the other hand, the signal from the output of the one-shot 14 is fed to the input of the logical element. OR 20 in the case when the other inputs of the logical elements OR 20, 21 are signals from other there are no automatic scaling devices, the pulse from the output of the logic element OR 20 is fed through the tracking machine to the input of the reversible pulse counter 5. Under the action of a pulse, the reverse pulse counter 5, the decoder b, change their state So that at the output of the decoder 6 corresponding to the first subband of the split, the voltage arrives at the resistor switching unit 7.

The key elements located in this block are shunting or, on the contrary, shunting sections of feedback resistors or sections of resistors in the input circuits of operational amplifier 1, which provides a change in the transfer coefficient of the adder and, therefore, the scale of the variable 1} at 10 pasj.

Consider the transfer of machine variable 1 | from the third subband to the second, i.e. transition 3-2.

The impulse from the comparison circuit llj, is fed to the input of the one-shot 15, the output signal of which blocks the work of the one-shot 14 from the prohibitory input. At the same time, the impulse from AOy & the one-shot 15 passes through the logical element OR 21 block, ka 4 mates to the input of the reversible pulse counter 5 via the bus by subtracting. Under the action of this pulse, the output state of the reverse pulse counter 5 changes, and consequently, the output state of the decoder b, which determines the state of the keys, and, consequently, the transfer coefficient of the adder across all inputs.

Similarly, the work of the device occurs at the transition 2-I.

Consider a 1-0 transition.

This process differs from those considered because the machine variable in the zero subrange changes from + UHG to - EGN or vice versa depending on the nature of the change. When the machine variable j enters the zero subrange from the zero output of the decoder 6, a signal arrives at the forward input of an AND 19 logic element (no signal is received at the inverse input), the output of which receives a signal through the logical elements OR 12 and 13 to prohibit the gain of one Innovator 15 and 16 Thus, the supply of signals from these single vibrators to the inputs of the corresponding 1 and logical elements OR 20 and 21 of the block 4 is interlocked when the machine variable Ij of the voltages 4-Ecr IErg crosses. When the mgshganiyu variable is located in other subranges, the signal does not arrive at the direct input of the logic element I 19 despite the appearance of signals from the output of one-shot 15 and 16 when the machine variable tj4 E c intersects. corresponding subrange. The nature of the operation of the device. When changing the machine variable in the subranges with negative numbers, is similar to that considered.

Let us assume that the machine variable is out and the limits of the numbers of the subranges for which the change of the transfer coefficient of the adder over the input was carried out using relay elements. In this case, as for positive subband numbers, the signal from the corresponding output of the decoder 6 is fed to the address input of the storage device 9. Information (code value of the transmission coefficient on the corresponding input) from the register of the storage device 9 is fed to the input of the digital-controlled resistance 10. This action changes the numerical value of the coefficient was transferred to the adder over all inputs at once or separately, depending on the change in the output variable.

The machine variable at the output of the adder can be functionally associated with other variables, which are also automatically scaled. This should be taken into account, since the change in the scale of a variable, i.e. switching to a subband with a different number associated with a change in the scale of a variable functionally associated with the first variable. For this purpose, multi-pass logic elements OR 20 and 21 are included, connected respectively by the addition and subtraction tires of the pulse counter 5. The signal nag input of one of these logic elements from the automatic scale changer causes a change in the clock counter of the pulse counter 5, which leads to the above-considered actions of other device units. The proposed device for the automatic change of scales in the AVM, in particular for the summing block, allows it to expand its functionality in comparison with the prototype, taken as the base object. Firstly, the introduction of an interface block allows the device to automatically change the mashtab, which participate in the solution of the dynamic problem to change the scale in terms of functionally dependent variables, into a single scaling system. Consequently, the range of solved dynsmic tasks expands. Secondly, the introduction of digital-controlled resistances in the input circuit and the storage unit allows one to expand the capabilities of the connection unit both in the number of inputs and in the mobility of the exhibition of the values of transmission coefficients. Thirdly, the dynamic range of the summing block is increased by the order of 3 to 4 times. This makes it possible to reduce the solution error by a factor of 2-3 by comparing with the solution obtained by ordinary means of analog computing technology without automatic scalers.

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Claims (1)

DEVICE FOR AUTOMATIC ZOOM V. ANALOGUE 'COMPUTER MACHINE, containing an operational amplifier, the input of which is connected to the first outputs of the input scale resistors and through the scale of the feedback resistor, with the output of the operational amplifier _t ' is the output of the device and connected to the input of the block of fixing subband boundaries .: the output of which is connected to the input of the false pulse inhibit block, a rever *, a counter and switching commutation units / decoder, a storage unit and digitally controlled resistances phenomena connected between the inputs of the device and the second outputs of the input large-scale resistors and connected by the control inputs to the outputs of the storage unit, the inputs of which are connected to the group of outputs of the decoder, the interface unit is turned on between the output of the false * impulse inhibit block and the input of the reversible counter, the output of which is connected to the input a decoder, the zero output of which is connected to the inhibitory input of the false pulse inhibit block, and the first and second outputs are connected respectively to the inputs of the input switching blocks (1 moat and switching unit of a large-scale feedback resistor. large-scale resisto; 1080154 2