FR2518637A1 - Control of deep drilling, esp. in winning petroleum, or gas - where computer contg. drilling model is used to feed optimum control signals to drilling plant - Google Patents

Abstract

The process and plant include a drill, which is driven in a known manner by a motor and winch receiving control signals from a digital/analogue (D/A) converter. The converter receives signals from a computer, which contains a drilling model and which receives signals from three sensors monitoring the drilling speed, the load on the drill, and the r.p.m. of the drill. The signals from the sensors are compared with optimum values derived from the drilling model so the control signals delivered by the D/A converter to the motor and winch can be adjusted to match the type of underground rocks etc. through which the drill travels, e.g. so excessive wear of the drill cutters can be avoided.

Description

 The present invention relates to the technique of drilling the ground and particularly relates to a soil drilling control method and a device implementing said method.

 The invention can be used for drilling wells, for example oil and gas.

 The mechanical destruction of rocks, for example during the drilling of oil and gas wells, implies that the control signals (loads on the drill bit or bit, and last rotation speed) are adjusted according to the lithological type of the drilling rocks (hardness, abrasiveness, elasticity) and other specific drilling conditions. A number of factors influencing the drilling process may be considered constant during the pass (service life of the bit), others are not; however, while wear patterns of bit bearings and teeth over time are evident, discontinuities and other rock lithological disturbances are unpredictable. In practice, the proper development of control signals requires constant monitoring. of the drilling process and is based on the state, at the moment, the drill bit and drilled land, regardless of the drilling system adopted: turbine, rotary or electric. It should be noted in this connection that there are no methods to directly control drill bit wear or the evolution of rock properties.

 There are various methods and various drilling control devices, allowing to build automated systems or not.

 In non-automatic systems, the choice of control signals is made by the operator (the driller) from the experience acquired. On average, the efficiency of the well-controlled drilling process is 25-30% lower than optimal efficiency.

 These non-automatic systems are currently much more common than automated systems.

 Automatic systems use adaptive models of the drilling process to form control signals. Before the pass, the parameters of the bit and the information on the other constant factors occurring during the pass are introduced into the adaptive model from the control panel. The parameters of the lands to be drilled, unknown before the beginning of the drilling (or known approximately), are determined during the course of this one. In this case, the pass time is divided into two periods: that of rock testing (validation of the model) and subsequent optimization of the control signals, and that of drilling at the optimum speed.

The duration of the rock test determines the inefficient use time of the whole and, in the case of deep well drilling, significantly compromises the yield, since with the increase in well depth the drilling time per the same trephine (tool-drilled footage) increases sharply.Moreover, frequent changes in the lithological properties of the terrain are possible, during which the system must repeatedly return to the test regime during the same pass ( One of the most important ways to improve the performance of deep and shallow drilling rigs, irrespective of the drilling method adopted, is the judicious use of the bit potential through process and control development.

 In existing automatic control systems of a drilling rig, the connection between the human operator and the drilling process is provided by a computer.

 These systems do not work in real time, nor do they allow online assessment of the technological situation.

 In such a system, the analog information from the sensors placed on the drilling rig is translated into digital, transcribed on perforated tape and transmitted using a teletypewriter to a computer center where the computer connects. periodically at the drilling rig and analyzes this information to correct drill programs.

The results of the calculation are transmitted to the drilling rig and used by the driller to manually control the actuators of the main mechanisms. In this way, neither an active search for information nor a real-time exploitation of its results is possible. Such an automatic control system of the drilling installation allows the optimization of the drilling regime by minimizing the cost of the meter drilled.

 On the other hand, said systems also do not allow the active search for information and their online operation, which is the cause of insufficient efficiency of the drilling installation.

 There is a method of controlling the drilling process employing an adaptive model of the drilling process, which serves to form the control signals acting on the drilling rig. This method consists in using two control regimes: a test regime for the rocks to be drilled and another for drilling itself.

 In the multi-cycle test regime, the values of the load on the tool and its speed of rotation are fixed in each cycle, the mechanical drilling speed corresponding to these instructions is measured and at the end of the cycle to the appropriate actuators the control signals for the next cycle. Depending on the results of the test regime, control signals of the drilling regime itself are formed. If, at this drilling regime, the values of the adjusted quantities, that is to say of the load on the tool and of its speed of rotation, deviate from the desired values, the test regime is again passed.

 This known method is based on the solution of the equation of the cott of a meter drilled to find the control signals to minimize this cost.

où V est la vitesse de forage,
P est la charge sur l'outil de forage,
PO est la charge sur l'outiltramenée à la vitesse
de forage nulle,
C est le coefficient caractéristique de la
z
qualité de l'outil,
H est la valeur conventionnelle d'usure de l'outil,
K est le coefficient de forabilité de la roche,
n est la vitesse de rotation de ltoutil,
est un coefficient déterminant l'influence de la
vitesse de rotation de l'outil sur la vitesse
de forage.In this case, said equation sffobtlent from the following expression of the drilling speed

where V is the drilling speed,
P is the load on the drill bit,
PO is the load on the tooltranslated to the speed
zero drilling,
This is the characteristic coefficient of the
z
quality of the tool,
H is the conventional wear value of the tool,
K is the coefficient of forability of the rock,
n is the speed of rotation of the whole,
is a coefficient determining the influence of the
speed of rotation of the tool on the speed
drilling.

 To determine the variable K and X values during drilling, a standard test program called the "five point method" is used. This method essentially consists of the following. In the first test cycle, arbitrary values are fixed for P and n and the corresponding value of V is stored in memory by varying the values D and n more or less in turn. another four test cycles, the drilling speed in each cycle being introduced into memory.

 Then the sixth test cycle is carried out with the same values of P and n as in the first cycle, that is to say that there are now in all five values of P and of n.

 If the drill hole V in the sixth cycle is the same as that in the first cycle, the test speed is completed. Then, from the solutions of the equation (I) where the stored measurements intervene, the coefficients K and 3 are calculated and adjusted; the coefficients thus obtained are introduced into the adaptive model and, after having calculated the control signals which are optimal for the drilling conditions under consideration, to be applied to the actuators of the drilling installation, the drilling regime itself is switched to. If, on the other hand, the drilling speed in the sixth cycle is other than that of the first cycle, the test regime is again switched to.

 The drilling regime with the control signals obtained continues as long as the difference between the measured drilling speed and the calculated drilling speed is small. If there is a considerable difference in the drilling speed compared to the calculated value, we return to the test speed.

 The device which implements said method comprises a drilling control panel, connected through a digital-to-analog converter to the actuators. The device has a computer carrying an adaptive model of the borehole and which contains a test-speed control signal formatter and an optimal control signal formatter, which have their outputs connected to the inputs of the digital-to-analog converter, and their inputs, to the respective outputs of sensors, a memory and a clock.

 The computer is connected to a mechanical drill speed sensor, a load sensor on the tool, and a rotational speed sensor of the tool. It is also connected to a control block of the values of the coefficients of the adaptive model.

 From the control panel, the coefficients and the control signals of the adaptive model are initialized and the test regime is initiated.

 The transitions between the test cycles are on the order of a suitably programmed clock and the respective control signals are output by the control signal trainer at the test speed. Once the test regime is completed, the corrected values of the coefficients are introduced into the adaptive model in order to optimize the control signals to be applied to the actuators.

 This known method and the device for its implementation have essentially the disadvantage that the system modifies differently from cycle to cycle the combinations of control signals determining the load on the tool and the rotational speed thereof in an order of succession of their execution fixed a priori also, in general, none of the six test cycles gives the optimal combination of the control signals.If, by chance, in one of the cycles, the combination parameters has been found to be close to the optimal combination, this can be ignored by the existing system which, by continuing the given program, will drive the regime to the non-optimal zone. As each of the six test cycles lasts for about ten minutes, the total duration of the test regime is relatively long and during all this time the use of the tool is not optimal. Given the long duration of the test regime, it is quite likely that the properties of the rocks to be drilled will change towards the last cycle so as to force the resumption of the test regime in six cycles, which will aggravate the damage. dfl audit disadvantage.

Another significant disadvantage to note is that after switching to the drilling regime the control signals which condition P and n remain constant, and in this case, even when the properties of the drilled lands do not change, the difference between the value the actual value of these signals and their value becomes increasingly larger, the optimum values themselves being variable as the tool wears naturally. The consequence is that the measured drilling speed deviates quickly from the
Saler calculated, which conflicts to resume 9th test regime with all its faults.

 As a result, the existing technical solution makes it possible to optimize the control signals only if it is necessary to drill the same layer for a long time and gives rise to a loss of efficiency of the drilling installation because of the prolonged drilling at the same time. Rational regimes under conditions of frequent changes in terrain characteristics during the pass, which is particularly detrimental to deep well drilling because of the limited tool life.

 The invention therefore relates to a method for controlling the drilling process and a device for carrying it out, making it possible, by modifying the control principle, to reduce the drilling times of the wells in the event of non-optimal control signals and, consequently, , to improve the performance of the drilling rig, which is particularly important in the case of drilling deep wells.

 This object is achieved by the fact that the drilling control method, based on the use of an adaptive model of the drilling process, has two control regimes, one of which is a test regime for drilling, and the other, a drilling regime itself, and consisting in that in regime of test rocks, which is a regime with several cycles, one fixes in each cycle the values of the regulated quantities of the drilling, that the drilling rate corresponding to the setpoints is measured, that, the last cycle being completed, the control signals to be applied to the respective actuators of the drilling rig, which uses the results of the test regime to form the signals, are developed. of control for the actual drilling regime and the transition signal from test to actual drilling, that in the event of a discrepancy between the regulated quantities and the specification, the drilling regime be discontinued pro In this case, the first test cycle is characterized, according to the invention, by determining, on the basis of the set values of the adjusted quantities and the approximate values of the adjustable coefficients of the adaptive model, the drilling speed, which compares the thus obtained drilling speed with the measured value of the same velocity in the given cycle, that according to the results of the comparison, the corrected values of the appropriate modifiable coefficients of the model are formed; adaptive, for closer approximation of optimal values 3 control signals constituting the instructions that condition the influence on the tool to the next cycle of the test regime, that in each subsequent cycle is used, to define the signals of controls, the coefficients adjusted to the previous cycle, that the control signals approach cycle cycle their optimum values for the drilling conditions considered, and that the control signal formed in two consecutive cycles where the measured speed is consistent with the calculated speed constitutes the setpoint occurring at the actual drilling speed.

où N est le numéro du cycle ;
V(N) est la valeur calculée de la vitesse de forage
dans le N-me cycle
Ki,Kj sont les coefficients ajustables du modèle
adaptatif correspondant aux grandeurs réglées
x.,xi sont les valeurs des grandeurs réglantes ;
i, j sont les numéros des grandeurs réglées, les
valeurs corrigées des coefficients ajustables
respectifs étant déterminées par les formules :

The adaptive model of the drilling process can be established from the following system of equations

where N is the cycle number;
V (N) is the calculated value of the drilling speed
in the N-me cycle
Ki, Kj are the adjustable coefficients of the model
adaptive corresponding to the adjusted quantities
x., xi are the values of the regulating variables;
i, j are the numbers of the quantities adjusted, the
corrected values of the adjustable coefficients
respective ones being determined by the formulas:

<tb> în <SEP> is <SEP> the <SEP> logarithm <SEP> Népérien <SEP> ctlnX
<tb> K, (N) = K. (Nl) + slgn <SEP> IlnV (N) -lnGi <SEP> glnV (N) -ln
<tb><SEP> 1 <SEP> 22 <SEP> X2j
<tb><SEP> i = 1 <SEP> J = 1 <SEP> (3)
<tb><SEP><SEP> -Ot <SEP> X <SEP>. <SEP>)
<tb> X, (N) = exlj6 <SEP> nu <SEP>.
<Tb>

<SEP> K. (N <SEP> lnK. (N-1) + signNV (N) -lnV3 <SEP>
<tb><SEP> j <SEP> j <SEP> 1 <SEP> m
<tb><SEP>; E <SEP> (lnX. <SEP>) 2+ <SEP> 5 <SEP> X.
<Tb>

<SEP> i = 1 <SEP> j '= 1
<tb> where sign means "sign den.

where V is the measured value of the drilling speed
oC is a coefficient whose value depends on the
difference between the measured drilling speed and
the calculated drilling speed.

 It is advantageous that the control signals, at the actual drilling rate, vary in stages with the drilling time, the periodicity and the degree of variation of said signals being determined using the adaptive model so that the signals remain. close to optimal signals given the wear of the teeth and bearings of the tool during drilling.

 It is possible, in order to adjust the coefficients of the adaptive model to the actual drilling regime, to define these coefficients in accordance with the prescribed control signals and drilling speed values relating to the specific drilling conditions.

 In the event of a change in the drilling conditions, it is necessary to move from the drilling regime proper to the test regime, the adaptive model coefficients obtained at the end of the actual drilling regime will then be adopted as initial values of the adjustable coefficients. of the first cycle of the repeated test regimen.

 It is more advantageous to adopt as regulated variables the load on the tool and the speed of rotation thereof.

 The object of the invention is also achieved by means of a drilling control device, comprising a drilling control panel, connected through a digital-to-analog converter to the actuators of the drilling rig, a speed sensor of drilling, a load sensor on the tool, a computer carrying an adaptive model of the drilling process, connected to the load sensors on the tool and its rotational speed, to the speed sensor and the control console , and provided to the trainer optimal control signals which has its output connected to the inputs of the digital converter, and its inputs, to the respective outputs of the clock and sensors of the load on the tick and its speed of rotation, a control block of the values of the coefficients of the adaptive model connected to the computer, the clock being also connected to the control console, said control device being, according to the invention, characterized in that it also contains a digital drill speed averager which has its inputs connected to the borehole speed sensor and the theorem output, that the computer has a data input sequencer coming from the command whose inputs are connected to the panel, a refiner of the coefficients of the adaptive model which has its inputs connected to the output of the digital averager and to the outputs of the data input sequencer, a first memory which has its inputs connected to the outputs of the coefficient refiner, and its outputs, at the inputs of the latter and at the inputs of the control block of the values of the modifiable coefficients of the adaptive model, a second memory whose inputs are connected through a block of data transmission to the corresponding outputs of the first memory, a drill regime trainer which has its inputs connected to the outputs of the control block of the coefficient values a and its outputs, at the input of the data transmission block, and a coefficient corrector of the adaptive model which has its inputs connected to the outputs of the second memory and the drill regime formatter, and its outputs, at the inputs of the trainer of optimal control signals.

 The trainer of the optimal control signals may comprise a tool servo type determining block, which has a group of inputs connected to the outputs of the clock and load sensors on the tool and its control. rotational speed, another group of inputs being connected to the outputs of the control panel, a block for calculating optimum setpoints for servocontrolling the tool according to the wear of its bearings and whose inputs are connected to the output from the block for determining the type of servo control of the tool, at the output of the clock, at the control panel, at the outputs of the coefficient corrector and at the output of the control block of the coefficient values, a calculation block optimal setpoints for servoing the tool according to the wear of its teeth and whose inputs are connected to the output of the block for determining the type of servo control of the tool, at the output of the control panel , at the exits of coefficient corrector and at the output of the control block of the values of the coefficients, a switching circuit composed of two groups of doors, each of which is respectively connected to the outputs of the calculation blocks of the optimal setpoint values for servocontrolling the tool in function. of the wear of its bearings and according to the wear of its teeth3 and, through a respective AND circuit, to the outputs of the block for determining the type of servo-control of the tool and to the clock, and two adders whose inputs are connected to the outputs of two groups of doors, the outputs of said adders constituting the outputs of the trainer of optimal control signals delivering the control signals to the actuators of the drilling rig.

 It is advantageous for the control block of the coefficient values of the adaptive model to contain an exponential circuit whose inputs are connected to the sensor of the speed of rotation of the tool and to the respective output of the first memory, a first multiplier of signals. whose inputs are connected to the load sensor on the tool and to the respective output of the first memory, a second multiplier of signals having its inputs connected to the output of the first multiplier and to the output of the exponential circuit, and its output at one of the inputs of a divider whose other input is connected to the output of the adder, one of whose inputs is connected through a variable resistor to an offset voltage source. and whose ~ other input is connected, through a third multiplier, to the respective output of the optimal control signal trainer, the output of the divider being connected to the respective input of the coefficient refiner and to the input of a comparator having its other input connected to the output of the numerical averager of the drilling speed, its output being connected through a gate at the respective inlet of the drill rig.

 It is rational that the data input sequencer from the control panel of the device comprises an electronic door group, that the input of each of said gates is connected to a respective code switch of the control panel, 11 input each of the gates being connected to the respective switch, regardless of the code-value analog converters connected to the respective electronic gates, that the coefficient corrector of the adaptive model comprises a group of electronic gates equipped with a multi-control input and placed at the input of a correction formatter composed of a memory circuit and a signal processing circuit whose outputs form the orifices of the set of the coefficient corrector of the adaptive model.

 It is possible, moreover, that the coefficient refiner of the adaptive model includes p9.core-refining circuit of the coefficient representative of the rock's forshability, to which is connected a refining circuit of the characteristic coefficient of the rotational speed of the rock. the tool, each of said circuits receiving at its inputs signals from the data input sequencer and the first memory, which provide information on the value of the coefficients of the adaptive model to the previous cycle, as well as the numerical averager of the speed of the drilling and control block of the values of the adjustable coefficients.

 The numerical averager of the drilling speed may contain a circuit for comparing and reading the signal representative of the drilling speed according to its envelope, the output of which is connected to an electronic gate which has its control input connected to the clock output and which delivers a signal triggering transmission of the signal characteristic of the average value of the drilling speed; the drilling regime trainer may comprise an OR circuit whose inputs constituting the inputs of the entire trainer are connected to the respective outputs of the control block of the values of the coefficients of the adaptive model, a first AND circuit whose inputs are connected to the respective outputs of the control block of the values of the coefficients and a second AND circuit of which one of the inputs is joined to one of the inputs of the circuit OU 'and whose other input is connected to the output of the first circuit AND, the bays duchrdit W anddudeuSe circuit AND constituting the outputs of the whole trainer.

 It is convenient for the data transmission block to be in the form of a set of gates making it possible to write in the second memory the adjusted values of the coefficients of the adaptive model.

 It should be noted that each of the blocks for calculating the optimal setpoints used to control the whole as a function of the wear of its bearings or as a function of the wear of its teeth may comprise an optimizer of which one of the inputs is connected to a trainer of the current wear value of the bearings or teeth of the tool, which has its inputs connected to the clock and to the output of the block for determining the type of enslavement of the whole; the optimizer provides signals representative of optimal setpoint load values on the tool and its rotational speed in accordance with the current wear of the bearings of the tool or its teeth; the block for determining the type of servo-control of the tool can comprise two-ways and each channel can be connected to the input of a respective switching circuit, the other input of each channel being connected to the clock; the first channel comprises a first divider whose inputs are connected to the sensor of the rotational speed of the tool and to the control panel, and a non-linear element which has its input connected to the load sensor on the tool their outputs being connected to the inputs of the first multiplier placed at the input of the switch of said channel; the second channel contains two multipliers in series; the first multiplier has its two inputs, and the second multiplier, its only input, connected to the rotational speed sensor of the tool, the output of the second multiplier is connected through the first adder and the second multiplier connected to the output of the first adder, at the first input of the second divider whose other input is joined through a third multiplier to the second adder which has one of its inputs connected to the control panel, and its second input, to the output of a fourth multiplier whose inputs are connected to the load sensor on the tool and the control panel; a third adder, which receives at one of its inputs the bias voltage, its other input being connected to the output of a fifth multiplier whose inputs are connected to the control panel and the output of the control signal formatter optimal; the second input of the second multiplier is connected to the control panel, the second input of the first adder being connected to the speed sensor.

 It is useful that the refinement circuit of the coefficient representative of the forspring of the rock comprises a first logarithmic circuit, placed at the output of the first memory and connected through the first multiplier to the first input of the first adder, a second circuit logarithmic connected to the output of the control block, a third logarithmic circuit placed at the output of the numerical averager of the drilling speed and a fourth logarithmic circuit connected to the sensor of the speed of rotation of the tool, that the second and third circuits logarithmic are connected to the inputs of the second adder connected to a gate having its outputs, one inverting and the other not, connected to the inputs of the first adder, the fourth logarithmic circuit is connected through the second multiplier and the third adder to the first input of the divider whose second input is connected across the three th multiplier at the output of the first logarithmic circuit its output being connected to the input of a gate, the second input of the third multiplier being directly connected, and the second input of the third adder, through the fourth multiplier, at the output of the first logarithmic circuit, and that the output of the first adder is joined to the input of an antilogarithmic circuit whose output constitutes the output of the whole of the coefficient refining circuit.

 It is also useful if the coefficient-of-rotation coefficient-refining circuit contains a first adder having one of its inputs connected to the output of the first memory, a first logarithmic circuit connected to the output of the control block values of the adjustable coefficients, a second logarithmic circuit connected to the output of the numerical averager of the drilling speed, a third logarithmic circuit connected to the sensor of the rotational speed of the tool, a fourth logarithmic circuit connected to the output of the circuit refining the coefficient representative of the rock forshability, that the first and second logarithmic circuits are connected through a second adder to the input of a gate having its outputs, one non-inverting and the other inverting, connected to the other inputs of the first adder, that the third logarithmic circuit is connected through a first multiplier and a series connection of a second multiplier and a third divider two input adder whose output is connected to the second input of the gate, that the fourth logarithmic circuit is connected through a third multiplier to the other input the third adder; the second input of the first multiplier being connected to the output of the second adder, and the output of the first adder forming the output of the entire circuit for refining the coefficient.

The invention will be better understood and other objects, details and advantages thereof will appear better in the light of the explanatory description which will follow of various embodiments given only as non-limiting examples, with references to attached non-limiting drawings in which
FIG. 1 represents the chronogram of the product of the quantities adjusted in the test regime
FIG. 2 is the chronogram of the regulated magnitudes of the drilling regime;
- Figure 3 shows the schematic diagram of the control device of the drilling rig, according to the invention;
FIG. 4 shows the trainer of optimal control signals, according to the invention
FIG. 5 illustrates the control block of the coefficient values of the adaptive model according to the invention;
FIG. 6 shows a data input sequencer from the control panel, according to the invention
FIG. 7 shows the coefficient corrector of the adaptive model according to the invention
FIG. 8 shows a refiner of coefficients of the adaptive model, according to the invention
FIG. 9 illustrates a refining circuit of the coefficient representative of the rock's forshability, according to the invention
FIG. 10 represents the refining circuit of the coefficient representative of the speed of rotation of the tool according to the invention.
FIG. 11 represents the numerical averager of the drilling speed, according to the invention
FIG. 12 illustrates the drilling regime trainer, according to the invention
FIG. 13 shows the data transmission block according to the invention
FIG. 14 shows the calculation block of the optimal setpoints used to control the tool according to the wear of its bearings
FIG. 15 is a diagram of the block for determining the type of servo control of the tool, according to the invention;
The drilling control process has two regimes: a test regime of the rock to be drilled and a drilling regime itself. The test regime of the rock is several cycles, the number of cycles not being fixed. In each cycle of this regime, the values of the loads on the tool and of its rotational speeds are defined, and the drilling speed corresponding to the said specified load values on the tool and the speed of rotation of the latter are measured.

où N est le numéro du cycle,
V(N) est la vitesse de forage dans le N-ème cycle,
Ki et K sont Aes coefficients aJustables du modèle
J
adaptatif, correspondant aux grandeurs réglées,
Xiet Xj sont les grandeurs réglantes et i et J sont
les numéros des grandeurs réglées.When a cycle ends, new signals are formed to be applied to the respective actuators acting on the tool. For this purpose, an adaptive model of the process is used in the following form

where N is the number of the cycle,
V (N) is the drilling speed in the N cycle,
Ki and K are Ajustable coefficients of the model
J
adaptive, corresponding to the adjusted magnitudes,
Xiet Xj are the regulating variables and i and J are
the numbers of the quantities adjusted.

In the first cycle, we adopt some approximate values of the adjustable coefficients of the adaptive model Ki and KJ OÙ, for exelrlple, Kj is the coefficient of forability of the rock and K is the coefficient indicative of the speed of rotation of the tool. In this cycle, one calculates, from said prescribed values of the load on the tool and its speed of rotation (which corresponds in the formula to a set of coefficients relating to Xi and X.) and said approximate values of
J adjustable coefficients, the drilling speed V (N) 'predictable for the cycle cfl course of the regime.

où V est la vitesse mécanique de forage mesurée dans le
cycle en cours.Then we compare the drilling speed measured V and the calculated drilling speed V (N) in the same cycle to find &alpha; , where &alpha; = In V (N) - ln V. After the comparison, we try to correct the values of the adjustable coefficients K and K of the adaptive model with the help of
i J formulas:

where V is the mechanical drilling speed measured in the
cycle in progress.

 it should be noted in this connection that in each cycle all the coefficients are adjusted simultaneously.

 Then, determined by any given procedure, the values of the control signals close to their optimal values constituting the instructions which condition the influence on the tick at the next cycle are determined by means of any existing method, and it is sought to maintain constant, during the cycle, the levels of the load on the tool and its speed of rotation.

 In each subsequent cycle, said sequence of operations is repeated using, in order to define the control signals, coefficients of the adaptive model adjusted to the preceding cycle, so that from cycle to cycle the control signals approximate their optimum values for the drilling conditions considered.

 The variation of the drilling velocity from one cycle to another is evaluated and, when in two consecutive cycles of the test regime there is indentity of measured and calculated values of the drilling speed, a signal is given which triggers the passage from said test regime to the actual drilling regime, the control signals formed in the last cycle then being used in the first cycle of the drilling regime proper. In the subsequent cycles of the actual drilling regime, variable control signals are adopted by calculation predetermined steps, ie control signals optimized according to the adopted quality criterion.

 In each cycle, the drilling speed is measured to adjust the coefficient and find the predictable value of the drilling rate. The coefficients of the adaptive model are adjusted from the adjustable coefficients of the previous cycle. If the quantities to be adjusted for drilling deviate from the definition, the said drilling regime itself is abandoned to take up the said test regime of the rock, and the values of the coefficients are used to adjust the coefficients of the adaptive model. aJustables established in the last cycle of the drilling regime itself.

 Thus, the idea of the proposed control method is that, in order to find the values of the regulated magnitudes, a single controlled drilling cycle is used by means of instructions which condition the magnitudes of load influence on the whole and the speed of rotation of the this one.

 The efficiency of the process according to the invention is illustrated in the timing diagram of FIG. 1, in which a complex index is plotted on the ordinate which is the product of the load on the tool by its rotational speed (Pn) and which characterizes the drilling regime, and on the abscissa, the drilling time (in this case, the cycle corresponding to the beginning of the test). With the classical search method (that of the "five points") (curve i), the system brutally varies from cycle to cycle the combinations Pn with a command change order specified a priori, also, in general rule, in none of the six test cycles these combinations are close to the optimum Figure 1 shows a case where in one of the stages the test regime is coincidentally consistent with the optimum, yet the control system the existing program remains insensitive and, by continuing the given program of modifications of the instructions, causes the regime to go to the non-optimal zone, since each test cycle must be sufficiently long (some 10 minutes) to allow the valid results. , the total operating life of the drilling rig in inefficient diets is quite significant.

 With the method according to the invention, during most of the search time, the parameters of the drilling regime are close to optimum (the first cycles being the most efficient, curve 2), the drilling efficiency is also it is much better during a test stage long enough (remember that the test is recurrent during the pass).

 The method according to the invention does not involve any preliminary delimitation of the drilling zone and the identification of the parameters is carried out so that the drilling is carried out in the best regimes. This increases the average drilling rate and tool-drilled footage by about 1.75 to 56.

 The method according to the invention is implemented using a drilling control device, the block diagram of which is given in FIG. 3 which shows a drilling rig 3 equipped with appropriate actuators or execution units. 4, for example an electric motor for rotating the tool and an electric motor for driving a winch for the creation of the appropriate load on the tool, which are widely known in the technical field considered and, therefore, will not be described here.

 The device comprises a sensor of the drilling speed 5, a sensor 6 of the load on the whole and a sensor 7 of the speed of rotation of the tool, all connected to a computer carrying an adaptive model.

The inputs of the actuators 4 are connected through a digital-to-analog converter 8 to a control panel 9.

 The computer contains a trainer of optimal control signals 10 which has its outputs 11 ~ connected to the inputs of the digital-to-analog converter 8, and its inputs, to a clock 12 and to the outputs 13 and 14 of the sensors 6 and 7. According to the In the invention, the control device also has a digital averaging unit 15, or numerical averager, of the drilling speed, the inputs of which are connected to the sensor 5 and to the clock 12. The computer comprises a unit 16 input, or sequencer, data from the control panel 9, a refining unit 17, or refiner, coefficients of the adaptive model, the inputs of which are connected to the output 18 of the averager 15 and to the outputs 19 of the sequencer 16, and two memories 20 and 21, the first of which (20) has its inputs connected to the outputs 22 of the refiner 17, and its outputs 23, to the inputs of this same refiner 17 and to the inputs of a block 24 for checking the values of the coefficients adjustable the memory chip (21) having its inputs connected via a data transmission block 25 to the respective outputs 23 of the memory 20.

 The computer also comprises a drilling regime former 26 whose inputs are connected to the outputs 27 of the block 24, its output 28 being joined to the input of the data transmission block 25, and a corrector 29 of the coefficients of the adaptive model, which has its inputs connected to the outputs 30 of the memory 21 and to the output 31 of the formatter 26, while its outputs 32 are connected to the respective inputs of the optimal control design trainer 10 whose outputs 33, 34 and 35 are connected to the input of the control block 24, to clock 12 and to the control panel 9, respectively.

 FIG. 4 shows the diagram of the optimal control signal forming device 10 composed of a block 36 for determining the type of servo-control of the tool, of a block 37 for calculating the optimal setpoint values for servocontrolling the tool according to the wear of its bearings, a block 38 for calculating the optimum setpoint values for servocontrolling the tool according to the wear of its teeth, and a switching circuit 39. the block 36 also comprises a first group of inputs connected to the output of the clock 12 and the outputs 13 and 14 of the sensor 6 of the load on the tool and duGpr7 i savitemede rotation, a second group of inputs, connected to the console of control 9 (FIG. 3).

 The inputs of the block 37 (FIG. 4) are connected to the output 41 of the block 36 of determination of the servo type 36, to the clock 12 and to the control panel 9, the inputs of the block 38 being connected to the output 42 of the block 36 for determining the type of control and the control panel 9 (Figure 3). The blocks 37 and 38 (FIG. 4) have a group of inputs connected via a block 40 of electronic gates to the outputs 32 (FIG. 3) of the corrector 29 and to the output of the control block 24.

 The switching circuit 39 (FIG. 4) contains two groups 43 and 44 of gates, each of which is connected to the outputs 45 and 46 of the blocks 37 and 38, respectively of the AND circuits 47 and 48, the outputs connected to the two groups. and 44 gates, their inputs being joined to the outputs of the block 36 and the clock 12, and two adders 49 and 50 whose inputs are connected to the outputs of the two groups 43 and 44. Types 51 and 52, respectively, of adders 49 and 50 constitute the outputs of the entire trainer 10 by which the control signals of the actuators 4 (FIG. 3) of the drilling rig 3 are delivered.

 The block 24 for controlling the coefficient values of the adaptive model comprises an exponential circuit 53 (FIG. 5), three multipliers 54, 55 and 56, a signal divider 57, a comparator 58 and an adder 59.

The inputs of the exponential circuit 53 are connected to the output 14 (FIG. 3) of the sensor 7 of the rotational speed of the tool and to the output 23 of the memory 20. The inputs of the multiplier 54 (FIG. 5) are connected to the output 13 (Figure 3) of the load sensor 6 and the corresponding output 23 of the memory 20, the output 60 (Figure 5) of the multiplier 54 being connected to an input of the multiplier 55, another input is connected to the output 61 of the exponential circuit 53.

 The divider 57 has its inputs connected to the output 62 of the multiplier 55 and to the output 63 of the adder 59 comprising input resistors 64 and 65 and a resistor 66 placed in a feedback loop; one of the inputs of the adder is connected through a variable resistor 67 to a source of offset voltage 68, its other input being connected to the output 69 of the multiplier 56. The inputs of the latter are connected to the output 33 (Fig. 3) of the optimal control signal trainer 10 and, through a variable resistor 70 (Fig. 5), to a voltage source 71.

 The output 72 of the divider 57 is connected to the corresponding input of the coefficient refiner 17 (FIG. 3) and to an input of the comparator 58 (FIG. 5), of which another input is connected to the output 18 (FIG. 3) of the digital averager. 15, its output 73 (Figure 5) being connected, through a door 74, to the corresponding input of the drill rig 26 (Figure 3).

 The data input sequencer 16 from the control panel 9 comprises analogue signal-coding converters 75 and 76 (FIG. 6), the inputs of which are connected to the outputs of the electronic gates connected in two groups 77 and 78. The input of each electronic gate is connected to a respective code switch 79 of the control panel 9 (FIG. 3), the control input 80 of each electronic gate (FIG. 6) being connected to a respective switch 81.

 For the sake of simplicity, it has been shown in the drawing only the connection of a single electronic gate, but it must be kept in mind that each electronic gate of the groups 77 and 78 is connected to the control panel 9 in the same way.

 The coefficient corrector 29 of the adaptive model (FIG. 3) contains a group of electronic gates82 (FIG. 7) having a common control input 83, and a two-way correction formatter 84 and 85 each of which comprises a memory and signal circuit. signal processing. The outputs of the channels 84 and 85 constitute the outputs 32 of the set of the corrector 29, their inputs being connected to the electronic gates.

 Each of the voices 84 (85) has, connected in series, an operational amplifier 86 looped through a capacitor 87 and preceded by a capacitor 88, and an output amplifier 89.

 According to the invention, the refiner 17 of the coefficients of the adaptive model (FIG. 3) contains a circuit 90 (FIG. 8) for refining the corresponding coefficient of the rock's forshability, connected by its output 91 to a circuit 92 of FIG. refining the coefficient corresponding to the rotational speed of the tool. The inputs of the circuits 90 and 92 are connected to the outputs 19 (FIGS. 3 and 6) of the data input sequencer 16, to the outputs 23 of the memory 20, to the output 18 of the digital averager 15, to the output 14 of the sensor 7 and at the output 93 (FIG. 8) of the block 24 for checking the values of the adjustable coefficients.

The outputs of the circuits 90 and 92 are the outputs 22 of the entire refiner 17.

 FIG. 9 gives the diagram of the circuit 90 for refining the coefficient corresponding to the forshability of the rock. The circuit 90 comprises four identical logarithmic circuits 94, 95, 96 and 97; the circuit 94 is connected to the output 23 of the memory 20 (FIGS. 9, 3), the circuit 95 is connected to the output 93 of the control block 24, the circuit 96 is connected to the output 18 of the digital averager 15, the circuit 97 being connected to the output 14 of the sensor 7.

 The circuit 90 includes adders 98, 99 and 100 and an inverter 101 with input resistors 102, 103 and 104, 105 and 106, 107 and 108 and 109, respectively, resistors 110, 111, 112 and 113 looping the operational amplifiers constituting the adders 98 to 101.

 It should be noted, moreover, that the circuit 90 comprises identical multiplier circuits 114, 11-5, 116 and 117, a divider 118 and an electronic gate 119.

 The logarithmic circuit 94 is connected to the input of the multiplier 114 connected in turn to the input of the adder 96. The logarithmic currents 95 and 96 are connected to the inputs of the amplifier 99 TSCcaded through the electronic gate 119 to the receiver. Inverter 101. The logarithmic circuit 97 is connected through the multiplier 116 to one of the inputs of the adder 100 whose other input is connected to the multiplier 117 which has its input connected to the output 120 of the circuit 94.

 The input of the divider 118 is connected directly to the output of the adder 900 and, through the multiplier 115, to the output 120 of the logarithmic circuit 94 and to the output of the adder 99, the output 121 of said divider 718 being connected to the input of the electronic gate 119. The outputs of the gate 119 are connected directly and via the inverter 101 to two inputs of the adder 98.

 At the output of the adder 98 is connected an antilogarithmic circuit 122 whose output forms the output 22 of the coefficient refiner 17.

 All circuits 94 to 97, 114 to 117, 122 and divider 118 are of conventional types. For example, embodiments of said circuits shown in Fig. 9 are as follows. Each of the circuits 94 to 97 comprises at its output an operational amplifier 123 looped by a capacitor 124 and a resistor 125, the corrector by reaction having resistors 126 and 127 and a capacitor 128. The amplifier 123 receives at its input, by the transistor 129 and resistor 130, a positive voltage. Transistor 129 has its emitter connected to that of usa transistor 131 whose collector is in direct connection with the input of an amplifier 132 and, through a resistor 133, with the output 23 (FIG. 3) of the memory 20. The operational amplifier 132 (FIG. 9) is looped by a resistor 134 and capacitors 135 and 136; the inputs of the amplifier 132 are connected by voltage dividers 137, 138 and 139 to a negative voltage source tD.

 The output of the operational amplifier 132 is connected through a resistor 141 to the emitters of the transistors -129 and 131.

 The circuit 94 contains negative voltage sources 142 and 143 and a positive voltage source 144.

Each of the multipliers 114 to 117 consists of an operational amplifier 145 looped by a network
RC (146, 147) and transistors 148 and 149 whose collectors are respectively connected, through a resistor 150 and a resistor 151, to a positive voltage source 152, and are connected directly to the inputs of the operational amplifier 145. The emitters of the transistors 148 and 149 have a corona point: one connected through a resistor 153 to a power source 154, and through a resistor 155, at the output 19 of the sequencer 16 (FIG. of transistor 149 (Fig. 9) being grounded through resistor 156 and connected through resistor 157 to the input of circuit 114.The base of transistor 148 is grounded through a resistance 158. At the input of the operational amplifier 145 is mounted a filter composed of a resistor 159 and a capacitor 160.

 The divider 118contains a multiplier 161 of which one of the inputs constitutes the input of the divider 118 and whose other input is connected through a resistor 162 to the input of an operational amplifier 163 and through a resistor 164 to a second input of the multiplier 161. The output of the operational amplifier 163, looped through a capacitor 165, is connected to the output of the multiplier 161 constitutes the output of the divider 118.

 FIG. 10 shows the coefficient-refining circuit 92 corresponding to the speed of rotation of the tool. This circuit comprises four mesomeric logarith circuits 166, 167, 168 and 169. The input of the circuit 166 is connected to the output 93 dulloc 24 (FIG. 3), the input of the circuit 167 (FIGS. 10 and 3) is connected. at the output 18 of the averager 15, the input of the circuit 168 is connected to the output 14 of the sensor 7, the input of the circuit 169 is connected to the output 91 (FIG. 8) of the circuit 90.

 The circuit 92 comprises adders 170, 171 and 172 using input resistance operational amplifiers 173, 174, 174 and 176, 177, 178 and 179, 180 and 181, respectively, looped by resistors 182, 183 and 184. The circuit 92 further comprises an electronic gate 185, identical multipliers 186, 187 and 188, an inverter 189 constituted by an operational amplifier at the input of which a resistor 190 is mounted and which is looped by a resistor 191, and a divider 192.

 The logarithmic circuits 166 and 167 are connected to the inputs of the adder 171, the output of which is connected to the electronic gate 185. The logarithmic circuits 168 and 169 are connected to each other through respective multipliers 187 and 1ss8. at the two inputs of the adder 172 which receives at its third input, through the resistor 181, a bias voltage, its output being connected to the input of the divider 192. The other input of the divider 192 is connected to the output of the multiplier 186 whose inputs are connected to the output of the adder 171 and to the output of the logarithmic circuit 168.

 The output of the divider 192 is connected to one of the inputs of the electronic gate 185 whose other input is joined to the output of the adder 171, its output being connected directly and via the inverter 189 at the two inputs of the adder 470. Two other inputs of the adder 170 are connected to the output 19 of the data input sequencer 16 (FIGS. 10 and 3) and to the output 23 of the memory 20, the output of FIG. the adder 170 constituting the output 22 of the coefficient refiner 17.

 FIG. 11 represents the diagram of the digital drill speed averager 15, which comprises a circuit 193 for comparing and reading the envelope of the signal representative of the drilling speed, at the output of which a door 94 is mounted, of which The control input is connected to the outputs 95 of the clock 12 (FIG. 3).

 The circuit 193 (FIG. 11) comprises an operational amplifier 196 looped by a diode 197 and a resistor 198 connected in series and whose common point is connected through a resistor 199 to a bias voltage source. The sxntree of the operational amplifier 196 is connected to a capacitor 200 connected through a diode 201 at the output of the sensor 5 of the drilling speed, through a diode 202 at the output of the operational amplifier 196, and through a resistor 203 to a power source 204.

The drilling regime trainer 26 (FIG. 3) comprises an OR circuit 205 (FIG. 12) and two circuits
AND 206 and 207. The inputs of the circuits 205 and 206 and one of the inputs of the circuit 207 are connected to the outputs 27 of the control block 24. The circuit 206 has its output connected to the second input of the circuit 207 whose outputs are connected to the inputs of the blocks 29 and 25 (FIG. 3) and constitute, respectively, the outlets 31 and 28 of the whole of the planter 26.

 Fig. 13 is shown in a conventional manner the housekeeping block 25 which consists of a set 208 of electronic gates for showing to the outputs 209 write validation signals of the adjusted coefficients of the adaptive model in the room. memory 21 (FIG. 3).

The block 37 (FIG. 4) for calculating the optimum setpoint values for servocontrolling the tool as a function of wear of its bearings and shown in FIG. 14 contains an optimizing or optimizing device 210 whose one of the inputs is connected to to a trainer 211 of the value of the wear of the bearings, the inputs of which are connected to the output 212 (FIG. -3) of the clock 12 and to the output 41 (FIG. 4) of the block 36 for determining the type of servo of the tool. The inputs of the optimizer 210 (FIG. 14) are connected to the outputs 213 (FIG. 3) of the control panel 9. At its outputs forming the outputs 35 of the block 37 (FIG. 4), the optimizer 210 (FIG. 14) provides signals corresponding to the optimal setpoint values of the load on the whole (POpt) and its speed of rotation (nOpt)
Block 38 (FIG. 4) for calculating optimum setpoints for servocontrolling the tool according to the wear of its teeth is also constituted, like block 37, by a circuit comprising an optimizer, so that it will not be described here.

 As optimizer 210 (FIG. 143, an optimizer of a type widely known per se can be used in blocks 37 and 38, so that it will not be described either.

 The trainer 211 of the value of the current wear of the bearings (or teeth) of the tool comprises an electronic gate 213 whose control input is connected to the output 212 of the clock 12, its other The output of an electronic gate 214 is connected to an inverter 217 looped through a capacitor 218 and whose output is more, connected through a resistor 219 to a second input of the gate 214 and is directly connected to an inverter 220 connected to the input of the optimizer 210.

 Block 36 (FIG. 4) for determining the type of servo-control of the tool, represented in FIG. 15, is two-channel, each channel being connected to the input of a switching circuit 221, 222, respectively, another input is connected to the output 21: 2 (Figure 3) of the clock 12. The first channel comprises a divider 223 connected to the output 14 of the sensor 7 (Figures 15 and 3) and the output 213 of the panel 9 a non-linear element 224 whose input is connected to the output 13 of the sensor 6 and a multiplier 225 which has its inputs connected to the respective outputs of the divider 223 and of the non-linear element 224, and its output, to the circuit of switching 221.

 The second channel comprises a divider 226 using multipliers 227 and 228 and whose input is connected to the output 14 of the sensor 7, an adder 229 placed at the output of the divider 226 and a multiplier 230 which has its inputs connected to the outputs of the adder 229, and its outputs, at the input of the divider 231 whose output is connected to the input of the switching circuit 222.

 The second channel further comprises a multiplier 232 which has its inputs connected to the output 13 (FIGS. 15 and 3) of the sensor 6 and to the output 213 of the control panel 9.

 The kind of the multiplier 232 is connected via the adder 233 to one of the inputs of the multiplier 234 which has its output connected to the second input of the divider 231.

 The control panel 9 has its output 213 connected to one of the inputs of a multiplier 235 whose other input is connected to the output 46 of the block 38, its output being connected to one of the inputs of an adder 236 which receives at its other input, through a resistor 237, the bias voltage of a source 238, the output of said adder 236 being connected to the second input of the multiplier 234.

 The switching circuits 221 and 222, which are identical, each comprise an electronic gate 239, one of whose outputs is connected to an operational amplifier 240 looped through a capacitor 241 and a resistor 242 connected through the electro-gate.

239, to the second feedback loop of the amplifier 240 preceded by a resistor 243.

 The electronic gate 239 and the operational amplifier 240 are connected, one by a resistor 244, and the other by a resistor 245, to an inverter 246 looped by a resistor 247.

 The output of the inverter 246 constitutes the output of the switching circuit 222 (221). The outputs of the switching circuits 221 and 222 are connected to a comparator 248 provided with a switching circuit of the output signal.

 The control device of the drilling rig operates as follows.

 Starting the device requires the following preliminary operations. The refiner of coeffi-.

 Adjustable sensors 17 receive through the data input sequencer 16 the signals from the control panel 9 and representative of the approximate values of the adjustable coefficients, and the trainer 10 of optimal control signals, the signals corresponding to the optimization constants. of the drilling process.

In the very first cycle of the rock test regime, the reference signals of the load on the whole and of its speed of rotation transmitted by the control panel 9 are applied via the digital-to-analog converters. to the respective actuators 4 which maintain at set values the load on the tool and its rotational speed during the given drilling cycle, and the clock 12 is triggered
The sensor 5 provides the digital averager with the drilling speed i5 with the instantaneous value of the drilling speed. The averager 15 averages the values of the drilling speed for a time set by the clock 12. At the expiry of this clock time the averager 15 is enabled by the circuit 195 to output by its output 18 a signal representative of the average drilling speed at the first test cycle at the coefficient refiner 17 and at the control block of the adjustable coefficient values 24. On a signal coming from the output 18 of the averager 15, the coefficient refiner 17 performs the refinement of the coefficients of the adaptive model.

The coefficients are also used for signals from the bit rotation speed sensor output 14, the data input sequencer outputs 19, and the block 24 output 93. control of the coefficient values of. adaptive template
The coefficients are refined simultaneously in two channels 90 and 92.

After the refining, the signals representative of the coefficients adjusted to the first cycle are sent, by the outputs 22, to the memory 20 which transfers them through its output 23 to the block 24 of con? Crble values of the coefficients of the model. Adaptive and data block 25.-
The block 24 receives signals characteristic of the drilling speed of the output 14 of the sensor 7, the output 13 of the sensor 6 of the load on the tool, the output 18 of the digital averager of the drilling speed 16, the output 23 of the memory 20 and the output 33 of the control signal generator 10. The block 24 calculates the theoretical drilling speed, which is compared to the average speed from the output 18 of the averager 15.

According to the result of the comparison (identity or non-identity of the signals), at the outputs 27 of the block 24 (if the signals are identical, at one of the outputs, otherwise, at the other output) signals are formed which are then applied to the trainer 26 (7th signal is issued by one of the outputs 27). At this regime, the signal at the output 27 connected to the OR circuit 205 and to the AND circuit 206 generates at the outputs 31 and 28 of the AND circuit 207 the validation signals respectively of the corrector 29 and the block 25. At the same time, a signal appears at the output of the OR circuit 205 connected to the optimal control signal trainer 10.

 On a signal appearing at the output 28 of the regime formatter 26 which conditions the electronic gates 208, the characteristic signals of the adjusted coefficients are stored in the second memory 21 and appear at its outputs 30.

 On a signal from the output 31 of the power trainer 26 applied to the control input of the group 82 of the electronic switches of the coefficient corrector 29, the memory 21 sends by its output 30 the signals representative of the coefficients adjusted on two parallel tracks 84 and 85 of the correctional trainer. In each of the channels 84 and 85, at the closing of the electronic gate, the amplifier 8q reproduces the output of the input signal and, when the electronic gate is opened, the instantaneous value of the input signal is set to the output 32.The signals from the output 32 of the coefficient corrector 29 are applied to the optimal control signal trainer 10, to the inputs of the electronic gates 40 which receive at their control inputs a signal from the speed trainer 26.

 The circuit 40 transfers the signals to the blocks 37 and 38. At the same time, the processing is carried out in the block 36 for determining the type of servo-control of the tool, which receives the signals from the output 13 of the sensor 6 of the load on the tool, the output 14 of the sensor 7 of the speed of rotation of the tool, the output of the clock 12, the multiple output 213 of the control panel 9 providing the constants of the process, and from the output of the calculation block 38, optimum setpoints for servocontrolling the tool according to the wear of its bearings. The block 36 supplies, via its output 41, the servo-type signal of the tool to the circuit AND 47 when the formation in the block 36 of the signal representative of the wear of the bearings of the tool precedes that of the characteristic signal of the wear of its teeth; in the opposite case, this signal is delivered by its output 42 to the AND circuit 48.

 Blocks 37 and 38 elaborate the signals corresponding to the current wear values of the bearings and the teeth of the tool during the given cycle of the borehole, which signals are applied to the optimizers 210 according to the wear of the bearings of the tool and following the wear of the teeth of it. The optimizers 210 deliver the signals representative of the optimal values nOpt and Popt resulting from the optimization of the control signals taking into account the wear of the bearings of the tool and that of its teeth to the respective groups of electronic gates 43 and 44.

The control inputs of the doors receive a control signal from the respective outputs of the circuits 47 and 48.

The circuits 47 and 48 in turn receive a bit servo-type signal and, on a signal from the clock 12, one of the circuits 47 or 48 provides a signal validating the output of the optimal control signals by the controller. one (43) or the other (44) group of electronic gates 43 and 44. The optimal values nOpt and Popt from the output 11 are transmitted by the outputs 51 and 52, through the digital-to-analog converters 8, to the actuators 4.

 The transfer of the control signals from the block 10 takes place on a signal of the clock 12.

 The graphical representation of the duct by means of a combination of the control signals n and P in the first cycle of the test regime with respect to their optimal combination is given in Figure 1 by the line F1.n ;.

After the application of the control signals to the actuators 4, it is the second cycle of the test regime (represented in FIG. 1 by the line P2, .n2)
who starts. The actuators 4 maintain during the cycles control signals (rotation speed signal of the whole n2 and load signal on the tool P2) at the levels specified by the block 10. After the averaging, the signal representative of the mechanical drilling speed from the sensor 5 appears on the signal given by the clock 12 at the output 18 of the digital averager 15.

The coefficient refiner 17 receives outputs 23 of the memory 20 the characteristic signals of the coefficients adjusted to the preceding cycle. At the same time, the con truble block 24 supplies at its output 93 to the refiner 17 the calculated value of the mechanical drilling speed, evaluated from the signals coming from the outputs 14 and 13 of the sensors 7 and 5. The refiner It performs the refining of the coefficients, the operating mode of its elements being that of the first cycle.

The memory 20, after having received the signals from the refiner 17, supplies them by its output 23 to the block 24
Block 24 compares, as in the first cycle, the values calcuiheet.Encours of the mechanical drilling speed. On a signal coming from the output 27, the regime trainer 26 begins to develop the operating mode of the device
If, in the two consecutive cycles, the drilling speeds are different, the circuits 205 and 207 deliver signals which are applied to the outputs 31 and 28 of the regimes processor 26, and the test mode continues.

 The corrector 29 and the formatter 10 deliver the modified level control signals, the interaction of the members in the corrector 29 and the formatter 10 being the same as in the first test cycle.

 On a signal provided by the clock output 212 12, the control signals thus formed are applied through the digital-to-analog converter 8 to the actuators 4, and the third cycle of the test regime begins (the combination P3 n3 of FIG. 1).

 In the following cycles of the regime, represented in FIG. 1 by the combinations P41 n4, P5 n5, P'6n'6, the device operates in the same manner as in the second cycle of the test regime. If the deviation of the mechanical drilling speed in two consecutive cycles is within the tolerance, the counter 208 stops conditioning the AND circuit 207, the signals at the outlets 31 and 28 are missing and the device switches to the actual drilling regime.

 In this case, in the PF cycle No. 6, the drill pattern trainer 26 cancels the signals at its outputs 31 and 28. In this regime, the signals at the outputs 32 of the correct signal 29 remain unchanged and the signal trainer The optimal control 10 delivers, on a signal coming from the output 212 of the clock 12, the signals adapted to the actual drilling regime (FIG. 2) through its outputs 11 and 35. In each cycle of the drilling the averager 15 takes the average of the drilling speed, the signal representative thereof being provided, on a clock signal, by the output 18 to the coefficient refiner 17.

After refining, the refiner 17 delivers the coefficients adjusted to the memory 20 and at the same time to the control block of the coefficient values 24. The block 24 supplies an inhibition signal for the outputs 31 and 28 of the block 26.

This is achieved by the fact that the two-bit counter compares the levels of the written and incoming signals, and that, if the comparison is true, circuit 207 is inhibited and the device continues to work at the actual drill rate. The signal for the change of the setpoints of the optimum control signals (incremental setpoints at the drill rate) provided by the block of optimal control signals is governed by signals from the output 212 of the clock 12.

 In the case where the value of the mechanical drilling speed exceeds the tolerance, the inhibit signal is canceled and the adjusted coefficients are h-transferred from the memory 21 into the coefficient corrector 29 and thence into the optimal control signal formatter. 10.

However, the device resumes the test regime.

 The digital drill speed averager 15 operates in the following manner. The mechanical drilling speed sensor 5 drives the circuit 193 for comparing and reading the signal according to its envelope. This is done continuously by the operational amplifier 196. The input signal transmitted by the diode 201 is stored by the capacitor 200 and, simultaneously, is compared by the amplifier 196 to the stored value transmitted by the diode 202. The Signal modification takes place when the variable input signal from the sensor 5 reaches local maximums. The digital averager 15 delivers the signal representative of the average speed of the bores on a signal coming from the output 195 of the clock 12.

 The refiner of adjustable coefficients 17 intervenes simultaneously by two channels (circuits 90 and 92).

The circuit 90 ensures the adjustment of the coefficient corresponding to the forshability of the rock.

 In the first cycle of the test regime, the refiner circuit 94 receives from the output 19 a signal representative of 1S-approximate value of the coefficient, fixed from the control panel 9.

 In subsequent cycles, the signal of the coefficient.

adjustable is applied to the circuit 94 of the refiner 17 from the output 23 of the memory 20. The circuit 94 is in fact a logarithmic amplifier using two operational amplifiers 123 and 132 and a pair of npn transistors 129 and 131. The transistors 129 and 131 operate at different collector currents.

In this case, the base-emitter potential difference is proportional to the logarithm of the ratio of collector currents of transistors 131 and 129. The collector current of transistor 131 constitutes the input current of the inverting amplifier 132. the collector is variable with the ratio of the input signal representative of the coefficient adjustable to the resistance value of the resistor 133.The collector current of the transistor 129 is proportional to the ratio of the voltage of the source 144 to the value of the resistance 130, the potential of the non-inverting input of the amplifier 123 being close to zero, the base-emitter voltage applied directly to the input of the amplifier 123 operating as a non-inverting amplifier whose gain is equal to 1 plus the ratio of the values of the resistors 127 and 126 is proportional to the logarithm of the product of the signal input / value ratios of the resistor 133 and the value of the resistor 130. The characteristic signal of the adjustable coefficient, transmitted by the circuit 94, appears at its output in the form of a signal proportional to the product of the gain of the operational amplifier 123 by the voltage base-emitter.

 The circuit 94 provides a signal on the multiplier 114 where this signal is multiplied by the signal from the output 19 of the data input sequencer 16. In the multiplier 114, on a signal representative of the adjustable coefficient, the transistor 148 (couple of bipolar transistors 148 and 1.49) modifies its internal resistance. The current of the source 154 changes its path and a differential signal, proportional to the product of the gain by the signal representative of the adjustable coefficient, appears between the collectors of said pair of transistors. The signal driving the second input of the multiplier 114 is applied to the transistors emitters 148 and 149 and the current through the resistors 150 to 151 is modified.The gain of the multiplier 114 is proportional to a constant multiplied by the signal ratio. on the second input of the circuit 114 to the value of the resistor 155. The signal at the output of the multiplier 114 is the product of the incoming signals by a constant. The output signal of multiplier 114 drives amplifier-adder 98, whose other inputs receive the corresponding polarity signal from gate 119. The necessary polarity of the input signal of amplifier 98 is provided by gate 119. which provides the appropriate switching, and by the inverter 101.

The gate 119 is conditioned by the amplifier-adder 99 which receives from the logarithmic circuits 96 and 95 a signal representative of the averaging of the appropriately converted drill speeds from the output 18 of the averager 15, and a characteristic signal the calculated drilling speed, from exit 93 of block 24.

The gate 119 receives at its main input a signal of the divider circuit 118 which has a dividend signal which is applied to the operational amplifier 163 through the resistor 162 from the multiplier 115, the divider being a signal applied to the signal. input of the multiplier 161 by the adder 100. The signal at the output of the adenitor 100 is conditioned by a signal from the output 14 of the sensor 7 of the rotational speed of the tool and converted by the circuits 97 and 116
In this case, the adder 100 receives at its other input input a signal of the circuit 94, converted by the multiplier 117.

 The appearance of the signal representative of the adjusted coefficient of rock dependability at the output 22 of the antilogarithmic circuit 122 is conditioned by the output signal of the adder 98. This signal constitutes the output signal of the coefficient-refining circuit 90. Representative of the rock forspring, By analogy with the circuit 90, in the circuit 92 for refining the coefficient representative of the rotational speed of the tool at the first cycle of the test speed, the signal representative of the value of the coefficient Adjustable, set from the control panel 9, is sent from the output 19 to the adder 170. In the following cycles, the signal representative of the adjustable coefficient goes from the output 23 of the memory 20 to the input of the adder 170 (to the input resistance 174). At the same time as the signal representative of the adjustable coefficient, a correction of the electronic gate 185 is applied to one input directly (the input resistance 176), and to the other input resistance (175) j through the inverter 16.

 In this case, the electronic loss 185 receives at its control input a signal from the adder 171 driven by a signal proportional to the average drilling speed from the output 18 of the averager 15 and by a signal proportional to the drilling speed. calculated in the given cycle, from output 93 of block 24.

 At the main entrance of the gate 185 there is a signal from the divider 192. The dividend signal then appears at the output of the multiplier 186.

The multiplier 186 receives at its inputs a signal proportional to the. difference of the average drilling speed and the calculated speed of the output of the amplifier 171 and a signal of the output 14 of the sensor 7, converted by the circuit 168.

 The ridge of the divider signal applied to the circuit 192 is filled by the output signal of the adder 172, which receives at its inputs the signals of the output 14 of the sensor 7 and the output 91 of the coefficient-refining circuit 90. representative of rock strength, converted into the respective logarithmic circuits 168 and 169 and the multipliers 137 and 188.

The control block 24 of the coefficient values of the adaptive model receives from the output 23 of the memory 20 signals proportional to the adjusted coefficients which attack the multiplier 54 and the exponential circuit 53. In this case, the multiplier 54 has at its second between a signal from the output 13 of the load sensor 6, the second input of the circuitononent 53 being driven by the output 14 of the sensor 7 rotational speed of the tool. The signals coming from the outputs 60 and 61 of the multiplier 54 and the circuit
The signal 53 representing the divider appears at the output 63 of the adder 59, which receives at one of its inputs the bias voltage of the source 68, and at its other input, a signal of the multiplier 56 representative of the product of two signals, one from the source 71 (the resistor 70 defines the value of the introduced constant), and the other, output 33 of the control signal trainer 10. The divider 57 provides at its output 72 a signal proportional to the drilling speed calculated at the comparator 58 whose second input is driven by a signal from the output 13 of the digital drilling rate averager. In the case of equality between the calculated and average drilling speeds, a signal from the comparator 58 proevokes the level change to the outlets 27 of the gate 74.

 The two channels of the block C of deterrnment of the type of servo-control of the tool (servo-control path of the tool as a function of the wear of its bearings and of the servo-sservement of the tool according to the wear of his teeth) work together. The servo path of the tool according to the wear of its -paliers receives from the output 213 of the control panel 9 a signal representative of the constant characteristic of the wear of the bearings of the tool; at the same time as the constant signal, the divider 223 receives a signal from the output 14 of the sensor 7, because it is a device of the rotational speed of the tool and acts as a drain. The divider delivers a signal to the multiplier 225, which receives its second between a signal of the output 13 of the load sensor 6, transformed through the non-linear element 224.

 The multiplier 225 supplies the product of the two signals to the switching circuit 221. The switching circuit 221 constitutes the output of the channel. - The validation of the circuit 221 is effected by a signal from the output 212 of the clock 12. If there is a signal at the output 212, the circuit 221 (same for the circuit 222) makes the in; bdgra- The integration of the input signal from the multiplier 225. The integration is carried out by an integrator (for the servo path of the tool according to the wear of its bearings, by the amplifier 240). If the signal at the control input of the circuit 221 disappears, its output signal is canceled and the circuit 221 resumes the integration of the input signal.

 The second channel receives from the output 14 of the sensor 7 a signal proportional to the speed of rotation of the tool which, after having been processed by the circuits 227 and 228, reaches the adder 229. The addition in the adder 229 takes into account the respective gains per entry.

 The adder 229 delivers a signal to the multiplier 230, which also receives a signal from the output 213 of the control panel 9. The signal applied by the multiplier 230 to the input of the divider-231 is the dividend. In this case, the divider 231 has, at its second input, an enyovenance signal from the multiplier 234 of the two signals, one from the adder 233 and the other from the adder 236.

 The emission of the signal by the adder 233 is conditioned by the output signal of the multiplier of two signals, that supplied by the output 13 of the load sensor 6 and that delivered by the output 213 of the control panel 9 which makes the sum with the signal coming from the other output of the desk 9.

 The representative signal of the second multiplying factor which is applied to the multiplier 234 is the sum of the constant signal, supplied by the resistor 237, and signals coming from the output 213 and the output 33 giving information on the current wear of the teeth. of the tool. The output signal of the divider 231 is transmitted through the switching circuit 222 (which has the same behavior as the circuit 221) to one of the inputs of the switching circuit comparator 248, its other input receiving a signal proportional to the servo value of the tool according to the wear of its bearings.

 At the outputs of the comparator 247 with a switching circuit, the signal varies as a function of the ratio of the signals applied to its input by the servo-control channel of the tool as a function of the wear of its bearings and the path of the enslavement of the whole depending on the wear of his teeth.

 The trainer 37 of the current wear value of the bearings of the tool (idem for the trainer 3 & of the current wear value of the teeth of the tool) is triggered by a signal sent to the circuit 221. output 41 of the block 36 which, after passing through the gate 214 conditioned by the output signal 212 of the clock 12, is applied to the integrator 217 using an inverter.

 The integratlon of the signal representative of the wear during the bearings lasts ie-time-of the conduction of the door 214.

 The inverter 220 transfers the signal to the optimizer 210 which receives from the outputs 213 of the control panel 9 the signals corresponding to the constants used to optimize the control signals. At the same time, the optimizer 210 receives from block 40 the signals representative of the adjusted coefficients. The optimizer 210 defines the optimal control signals considering that the allowable wear of the bearings of the tool during drilling will be earlier than that of its teeth.

The optimal instructions for servicing the tool according to the wear of its bearings appear at the outputs 35 of the optimizer 210-since no new signal is provided by the trainer 37 of the current wear value of the bearings of the whole .

 The formation of the optimal instructions for servoing the tool according to the wear of its teeth is done by the trainer 37-. in a similar way. According to the signal coming from the block 36 for determining the type of enslavement of the whole, the actuators 4 receive the optimal control signals from the electronic gates 43 and / or Z.

 The present invention makes it possible to improve the efficiency of the drilling, deep wells in particular, by finding the optimal drilling speeds for each ground to be drilled as well as by a judicious use of the potential of the tool.

Claims (20)

R E V E N D.I C AT IO N S  A method of controlling a soil foaming process, of the type based on the use of an adaptive model of the drilling process and consisting of two control regimes: a test regime of the rocks to be drilled and a drilling regime itself, that the test regime of the rocks, which is several cycles, is specified in each cycle the values of the calibrated values of the borehole is measured the drilling speed corresponding to the set values, and, at the last completed cycle, the control signals to be applied to the respective actuators of the drilling rig are developed, the results of the test regime are used to form the control signals for driving the actual drilling regime. and the transition signal from the test speed to the actual drilling speed, and in the event of a discrepancy between the adjusted and specified quantities, the drilling regime itself is again switched to the test regime. i, said method being characterized in that, in the first test cycle, the drilling speed is determined from the set values, the adjusted magnitudes and the approximate values of the adjustable coefficients of the adaptive model, which is compared with the speed of drilling thus obtained at the value of the drilling speed measured in a given cycle, that as a function of the results of the comparison, the corrected values of the respective adjustable coefficients of the adaptive model serving to bring closer to their optimum values the control signals constituting the instructions which condition the influence on the tool at the next cycle of the test speed, that in each subsequent cycle the coefficients adjusted to the preceding cycle are used to define the control signals, the control signals then approaching from cycle to cycle their optimum values specific to the given drilling conditions, and that the control signal-fo in two conscious cycles where the measured velocity coincides with the velocity computed constitutes that which will be at the rate of drilling.  Method according to claim 1, characterized in that the adaptive model of the drilling process is established from the following system of equations

 where N is the cycle number  V (N) is the calculated value of the drilling speed  in the Nth -cycle  Ki, Kj are the adjustable coefficients of the model  adaptive corresponding to the adjusted quantities;  Xi, Xj are the values of the regulating quantities -  i, j are the numbers of the adjusted quantities, the corrected values of the respective adjustable coelficients being determined by the formulas

 where V is the measured value of the drilling speed  O (is a coefficient whose value depends on ia  difference between the measured drilling speed and the  calculated drilling speed.  3. Method according to one of claims 1 and 2, characterized in that the control signals at the drilling rate itself vary by 3paliers during drilling, the periodicity and the degree of variation of the signals being determined at 1 using the adaptive model so that the signals remain close to optimal signals given the wear of the teeth and bearings of the tool during drilling.  4. Method according to one of claims 1, 2 and 3, characterized in that in order to adjust the coefficients of the adaptive model drilling regime itself is defined in accordance with the prescribed control signals and values the drilling speed considered.  5. Method according to one of claims 1, 2, 3 and 4, characterized in that, if the drilling speed undergoes a large variation compared to that calculated, the drilling regime itself is abandoned to resume the operating regime. In this case, the coefficients of the adaptive model obtained at the end of the actual drilling regime are adopted as the initial values of the adjustable coefficients of the first cycle of the new test regime.  6. Method according to one of claims 1 to 5, characterized in that the role of regulated variables is filled by the load on the tool and its speed of rotation.  7. Control device for the implementation of the method according to claim 1, of the type comprising a control panel of a ground drilling process, connected through a converter-digital-analog to the actuators of the installation of drilling, a drill speed sensor, a load sensor on the tool, a tool rotation speed sensor, a computer carrying an adaptive model of the drilling process, connected to the sensor of the drill, charge on. the tool and the tool speed sensor, the drilling speed sensor and the control panel and having an optimal control signal formatter which has its output connected to the inputs of the digital converter, and its inputs, at the respective outputs of a clock and load sensors on the tool and its rotational speed, a coefficient control block of the coefficients of the adaptive model connected to a computer, the clock being connected, it also, at the control panel, said device being characterized in that it comprises a digital averager of the drilling speed (15) which has its inputs connected to the sensors (6) and (7) of the load on the tool and its rotational speed, at the drilling speed sensor (5) and at the output of the clock (12), that the computer having an adaptive model of the drilling process comprises a sequencer (data input from the control panel (9), whose e Ntrées are connected to said desk, a refiner (17) coefficients of said adaptive model, which has its inputs connected to the output of the digital averager (15) and the outputs of the data input sequencer (16), a first memory (20) ) having its inputs connected to the outputs of the coefficient refiner (17), and its outputs, to the inputs of the latter and to the inputs of the block of control (24) of the values of the coefficients of the adaptive model, a second memory (21) ) whose inputs are connected through a data transmission block (25) to the respective outputs of the first memory (20), a drill regime trainer (26) which has its inputs connected to the outputs of the block (24). ) of control of the coefficient values, and its outputs, at the input of the data transmission block (25), and a corrector (29) of the coefficients of the adaptive model, which has its inputs connected to the outputs of the second memory (21) and the trainer (26) of the regimes drilling, and outputs, to the formatter respective inputs (10) of optimal control signals.  8 Apparatus according to claim 7, characterized in that its trainer of optimal control signals comprises: a unit of determination of the type of as.érvissement of the tool, which has a group of inputs connected to the outputs of the clock and sensors of the load on the whole and its speed of rotation, another group of inputs being connected to the outputs of the control panel, a block of calculation of the optimal setpoints used to enslave the tool according to the wear of its bearings and whose inputs are connected to the output of the block of determination of the type of enslaving of the tool, the exit of the clock, the control console, the outputs of the correcteur de coe44icients and the output of the control block of the values of the coefficients aJustables, a block of computation of optimal setpoints serving to enslave the tool according to the wear of its teeth and whose inputs are connected to the output of the block cze determining the type of ass actuation of the tool, at the output of the control panel, the outputs of the coefficient corrector and the output of the control block of the values of the coefficients, a switching circuit composed of two groups of doors each of which is respectively connected to the. outputs from the calculation blocks optimal setpoint values to control the tool according to the wear of its bearings and the wear of its teeth, and through the respective ET circuit, to the outputs of the determination block the type of control of the tool and the clock, and two adders whose inputs are connected to the outputs of two groups of doors, the outputs of said adders constituting the outputs of the trainer of optimal control signals delivering the control signals to the actuators of the drilling rig.  9. Device according to one of claims 7 and 8, characterized in that its control block of the values of the coefficients of the adaptive model comprises an exponential circuit whose inputs are connected to the speed sensor of rotation of the tool and at the respective output of the first memory, a first multinactor whose inputs are connected to the load sensor on the tool and to the respective output e the first meȯire, a second multiplier which has its inputs connected to the output of the first multiplier and at the output of the exponential circuit, and its output, to one of the inputs of a divider whose other input is connected to the output of the adder which has one of its inputs connected through a variable resistor to a source of offset voltage, and its other input, through a third multiplier, to the respective output of the optimal control signal former, the output of the divider being connected to the respective input of e the coefficient refiner and the input of a comparator which has its other input connected to the output of the numerical averager of the drilling speed, its output being connected through a gate at the respective input of the regime trainer drilling.  10. Device according to one of claims 7 to 9, characterized in that its input sequencer data from the control panel of the device comprises a group of electronic doors, the entryde each of said doors being connected to the switch respective code of the control panel, the control input of each door being connected to a respective switch, and analog code-value converters connected to the respective electronic doors.  11. Device according to one of claims 7 to 10, characterized in that its coefficient corrector of the adaptive model has a group of electronic gates with a multple control input and placed at the input of a correction formatter It consists of a memory circuit and a signal processing circuit whose outputs form the outputs of the set of coefficients corrector of the adaptive model.  12. Device according to one of claims 7 to 11, characterized in that its coefficients refiner of the adaptive model comprises a refining circuit of the coefficient representative of the forspring of the rock, to which is connected a coefficient refining circuit characteristic of the speed of rotation of the tool, each of said circuits receiving at its inputs signals from the data input sequencer and the first memory which provide information on the value of the adaptive model coefficients to the previous cycle, thus ~ only numerical averager of the drilling speed and control blo of the values of the adjustable coefficients.  13. Device according to one of claims 7 to 12, characterized in that its numerical averager of the drilling speed comprises a circuit for comparing and reading the signal representative of the drilling speed according to its envelope, the output of which is connected. an electronic gate which has its control input connected to the output of the clock and which delivers a signal triggering the transmission of the signal characteristic of the average value of the drilling speed.  14. Device according to one of claims 7 to 13, characterized in that its drilling regime former comprises an OR circuit whose inputs constituting the inputs of the entire trainer are connected to the respective outputs of the value control block of coefficients of the adaptive model, a first AND circuit whose inputs are connected to the respective outputs of the control block of the values of the coefficients and a second AND circuit which has one of its inputs joined to one of the inputs of the OR circuit, and its other input, at the output of the first circuit AND, the outputs of the circuit CU and the second AND circuit constituting the outputs of the entire trainer.  15. Device according to one of claims 7 to 14, characterized in that its data transmission block is constituted by a set of doors for entering in the second memory the adjusted values of the coefficients of the adaptive model.  16. Device according to claim 8 and one of claims 9 to 15, characterized in that its block of calculating optimal setpoints suave to enslave the tool according to the wear of its bearings comprises an opti; , whose one of the inputs is connected to a trainer of the current wear value of the bearings of the tool, which has its inputs connected to the clock and the output of the block of determination of the type of servo of the bit, that the optimizer provides signals representative of the optimal setpoints of the load on the tool- and its speed of rotation in accordance with the wear in progress of the bearings of the tool.  17. Device according to claim 8 and one of claims 9 to 16, characterized in that its block for calculating optimal set values for servocontrolling the tool according to the wear of its teeth comprises a trainer of the current wear value of the teeth of the tool, which has its inputs connected to the clock and to the output of the block for determining the type of control of the tool, and an optimizer connected to the output of the trainer of the current wear value of the teeth of the tool, which provides signals representative of the optimal setpoints of the load on the tool and its rotation speed in accordance with the wear of the teeth of the tool. 'tool.  18. Device according to claim 8 and one of claims 9 to 17, characterized in that its block for determining the type of control of the tool comprises two channels and that each vole-- is connected to the input of a separate switching circuit, 11 other input of each channel being connected to 1 "clock, the first channel comprises a first divider whose inputs are connected to the sensor of the speed of rotation of the tool and the control panel, and a non-linear element which has its input connected to the load sensor on the tool, their outputs being connected to the inputs of the first multiplier placed at the input of the switch of said channel, the second channel comprises two serial multipliers, that the first multiplier has its two inputs, and the second multiplier, its only input, connected to the rotational speed sensor of the whole, that the output of the second-multiplier is connected through the first adder and the e second multiplier, connected to the output of the first adder, to a first input of the second divider of which another input is joined through a third multiplier to the second adder which has one of its inputs connected to the control panel, and its second input, at the output of a fourth multiplier whose inputs are connected to the load sensor on the tool and the control panel, a third addWrener which receives at one of its inputs the bias voltage, its other input being connected to the output of a fifth multiplier whose inputs are connected to the control panel and the output of the trainer of optimal control signals, that the second input of the second multiplier is connected to the control panel, the second input of the first adder being connected to the speed sensor.  19. Apparatus according to claim 12 and one of claims 8 to 11 and 13 to 18, characterized in that the refinement circuit of the coefficient representativeof the rock's forsistance comprises a first logarithmic circuit, placed at the output of the first memory and connected through the first multiplier to the first input of the first adder, a second logarithmic circuit connected to the output of the control block, a third logarithmic circuit placed at the output of the numerical averager of the drilling speed and a fourth logarithmic circuit connected to the sensor of the speed of rotation of the tool, the second and third logarithmic circuits are connected to the inputs of the second adder connected to a gate which has its inputs, one inverting and the other non-inverting, connected at the inputs of the first adder, that the fourth logarithmic circuit is connected across the second multiplier and the third ad a converter at the first input of the divider whose input gate is connected through the third multiplier to the output of the first logarithmic circuit, its output being connected to the input of a gate, the second input of the third multiplier being directly connected, and the second input of the third adder, through the fourth multiplier, at the output of the first logarithmic circuit, and that the output of the first adder is connected to the input of an antilogarithmic circuit whose output constitutes the overall output of the coefficient refining circuit.  20. Device according to claim 12 and one of claims 8 to 11 and 13 to 19-, characterized in that the refining circuit of the coefficient representative of the speed of rotation comprises a first adder which has one of its inputs connected to the output of the first memory, a first logarithmic circuit connected to the output of the control block of the values of the adjustable coefficients8 a second logarithmic circuit connected to the output of the numerical averager of the drilling speed, a third logarithmic circuit connected to the sensor of the rotational speed of the tool, a fourth logarithmic circuit connected to the output of the refinement circuit of the coefficient representative of the rock's forshability, that the first and second logarithmic circuits are connected through the second adder to I input8 of a door that has its outputs, one non-inverting and the other inverting, connected to the other inputs of the first addononneur, that the e third logarithmic circuit is connected, through the first multiplier and a series connection of the second multiplier and the third adder, to two inputs of the divider whose output is connected to the second input of the gate, that the fourth logarithmic circuit is connected through the third multiplier to the other input of the third adder, the second input of the first multiplier being connected to the output of the second adder; the output of the first adder forming the output of the entire coefficient refining circuit.