Optronic sight having a critical mode, notably anti-resonance, including a variable fundamental frequency, and a motorized vehicle including such a sight

Abstract

This optronic sight for a motorized vehicle, such as an aircraft, marine vehicle, or land vehicle, comprises: a sighting module (13) capable of being moved around a first axis (X) and a second axis (Y) not parallel to the first axis; means (14, 15) for moving the sighting module around the first and second axes; and a feedback loop for controlling a position parameter of the sighting module based on a setpoint, comprising an adaptive feedback controller (16) capable of calculating a command for a controlled device having a critical mode that modifies the device's response. It includes means (23) capable of determining a fundamental frequency of the critical mode that varies according to an operating parameter of the controlled device, the controller (16) being calculated from the fundamental frequency determined to compensate for the anti-resonance or resonance mode. Abstract figure: Figure 5

Description

Title of the invention: Optronic sight having a critical mode, in particular an anti-resonance mode, comprising a variable fundamental frequency, and a motorized device comprising such a sight. Technical field of the invention

[0001] The present invention relates to the adaptive control of an optronic sight for a motorized vehicle such as an aerial, marine or land vehicle, that is to say the control of such a sight which is capable of compensating for disturbances which affect the sight. Prior art

[0002] With reference to Figures 1 and 2, which illustrate an optronic sight 1 for a motorized vehicle and an operating diagram of such a sight according to the prior art, an optronic sight 1 comprises a sighting module 2 including a set of sensors, in particular cameras and / or pointing devices defining a line of sight Ldv of the optronic sight 1 corresponding to the optical axis coming out of one of the sensors.

[0003] The aiming module 2 is placed on a support 3 fixed to the motorized vehicle and can move along two axes X and Y under the action of movement means 4 and 5 which may include cardans operated by motors controlled by control means 6.

[0004] The purpose of the optronic sight 1 is to orient the line of sight Ldv towards a target regardless of the movements of the motorized vehicle and / or the target, and regardless of the environment and external disturbances (atmospheric conditions, etc.) or internal disturbances within the device. To this end, the sighting module 2 includes means for continuously measuring angular data 7, comprising a gyrometer in the case of measuring angular velocity or a gyroscope to measure the angular position of the line of sight Ldv.

[0005] The carrier vehicle, by its movements or its motorization regimes, generates angular disturbances which deteriorate the stabilization of the line of sight Ldv of the optronic sight 1. It is therefore necessary to implement a process allowing the image to be stabilized precisely and therefore in particular to correct the speed or the angular position of the line of sight Ldv.

[0006] The viewfinder is thus equipped with a corrector 8 which receives the angular data measured by the measuring means 7 and which acts on the control means in order to compensate for the disturbances which act on the viewfinder 1.

[0007] To reject the vibrational disturbances acting on the sighting module 2 and thus make the sight line Ldv fixed in an inertial frame, it is necessary that the sum of the torques, i.e. the motor torque Cmot, the torque due to the disturbances and the friction torque Cf due to the cardan bearings, applied to the sighting module 2 be zero.

[0008] For this purpose, as illustrated in [Fig. 2], it is conventionally known to use a control loop 9 capable of acting on the angular data (velocity or position) of the line of sight Ldv. Each block of said control loop 9 can be designed as a system, that is to say, a set of relations linking inputs and outputs which can be made explicit using transfer functions.

[0009] Reference may be made to document FR 3 130 023 which describes an example of adaptive servo control of an optronic sight capable of compensating for disturbances caused by an on-board device, such as a cold machine, which may affect the line of sight.

[0010] The purpose of the servo loop 9 is to enable the means of movement 4 and 5 to generate a torque Cmot which compensates in particular the friction torque Cf at the level of the motorized gimbals to stabilize the angular orientation of the line of sight, when a carrier vehicle carrying the sight moves angularly.

[0011] As shown in Figure 2, the control loop 9 comprises a digital part including a comparator 10 ensuring the comparison between a sampled measurement ymk of the modeled angular data ym (position or angular velocity) of the line of sight and a reference yck to deliver a control error £k to a linear and time-invariant compensator K, and an analog part including transfer functions Hmot and Hcardan of the motor and the gimbals, respectively, and a transfer function Hgyro modeling the dynamics of the measurement of the angular data (position or angular velocity) of the line of sight.

[0012] The Hgyro transfer function is based either on the measurement y of the line-of-sight position obtained by a gyroscope, or on the measurement y of the angular velocity of the line of sight obtained by a gyrometer. The measurement of the modeled angular data of the line of sight ym then passes through an Analog-to-Digital Converter (ADC) and is thus sampled to deliver a sampled measurement ymk to the comparator 10.

[0013] The transfer function Hmot receives, on the one hand, an analog control voltage u corresponding to a digital control uk delivered by the controller K and then converted by a Digital-to-Analog Converter (DAC) and, on the other hand, an analog voltage ue corresponding to a back electromotive force feedback obtained based on a constant back electromotive force Ke applied to the speed of movement Q of the line of sight.

[0014] The electromechanical torque Cmot supplied by the motor actuates the cardans modeled by the transfer function Hcardan in order to compensate or cancel the error ek due in particular to the disturbing friction torque Cf in the cardan bearings.

[0015] The software implementation of the compensator K is in the form of a combination (sum and / or product) of second-order digital linear filters. It is linear and time-invariant.

[0016] The compensator K is also calculated to compensate for a mechanical mode C that appears in the mechanical transfer function Hcardm, and therefore a fortiori in the complete transfer function of the viewfinder between electrical voltage u and angular measurement y. The frequency of this anti-resonance mode varies with the temperature T of the system, but the compensator, which is stationary, does not take this variation into account, which is likely to cause instability in the control system for significant temperature variations.

[0017] Indeed, the gain of the mechanical transfer function Hcardun^ between the useful torque and the gyrometric speed, as a function of frequency, is given by the Bode diagram illustrated in [Fig.3].

[0018] The gain of the transfer function of a stationary speed controller between the gyrometric speed and the electrical control voltage of the motor, as a function of frequency, is given by the Bode diagram of [Fig.4].

[0019] The corrector must therefore have a local amplification intended to compensate for the anti-resonance present in the mechanical transfer function of the system to be controlled at the fundamental frequency fv of the anti-resonance mode.

[0020] However, the mechanical anti-resonance mode exhibits significant frequency variability with temperature. The controller synthesized for a system at room temperature, without taking into account the frequency variation of the mechanical anti-resonance mode, is therefore completely unsuitable for extreme temperatures. Under these conditions, the feedback loop can become unstable.

[0021] The variability of the anti-resonance mode as a function of temperature is also reflected in the electrical transfer function via the back electromotive force feedback, itself proportional to the angular displacement rate of the line of sight. Presentation of the invention

[0022] The aim of the invention is therefore to overcome the aforementioned drawbacks and to provide an optronic sight for motorized vehicles such as aircraft, marine or land vehicles, in which the performance of the control loop remains optimal, despite the presence of a critical mode, in particular anti-resonance which appears in the controlled mechanical system, this critical mode having a fundamental frequency that varies in the system to be controlled.

[0023] The invention therefore relates to an optronic sight for a motorized vehicle such as an aircraft, marine or land vehicle, comprising: - a sighting module capable of being moved around a first axis and a second axis not parallel to the first axis; - means for moving the aiming module around the first and second axes; and - a servo loop to control a position parameter of the aiming module on a setpoint, including an adaptive servo controller capable of calculating a command for a controlled device having a critical mode modifying the response of the device.

[0024] The viewfinder includes means capable of determining a fundamental frequency of the critical mode which varies according to an operating parameter of the controlled device, the corrector being calculated from the fundamental frequency determined to compensate for the critical mode.

[0025] Critical mode is understood to mean a mode that disturbs the response of the controlled device, such as a resonant or anti-resonant mode, at a natural frequency, when it is subjected to a control, involving amplification or, on the contrary, attenuation at said frequency.

[0026] In one embodiment, the fundamental frequency of the critical mode is variable depending on the temperature, the means suitable for determining a fundamental frequency of the critical mode comprising a temperature sensor and a lookup table between temperature values ​​and fundamental frequency values.

[0027] In another embodiment, the fundamental frequency of the critical mode is estimated as a function of the back electromotive force produced by the controlled device, as a function of a data representing the angular velocity of the aiming module, the means suitable for determining a fundamental frequency of the critical mode including means for calculating a transfer function between the current supplying the controlled device and an output voltage of the corrector.

[0028] In various embodiments, the critical mode modifying the response of the device is a mechanical anti-resonance mode or, alternatively, a mechanical resonance mode.

[0029] The servo position parameter of the aiming module can be the angular position of the aiming module or the speed of movement of the aiming module.

[0030] Advantageously, the adaptive controller includes a Linear Variable Parameter (LPV) controller.

[0031] Said adaptive controller can follow a state representation according to the following formula: xk+l = ^(Jvk)xk + ^(Krk)Ek uk = C(fvk)xk + 0(^)¾ — ^vk — ^max where xk is the state variable of the controller, ek is the input control error of the adaptive controller, uk is the digital control of the means of movement calculated by the adaptive controller, fmin and fmax are two frequencies bounding the fundamental real-time frequency f of the resonance or anti-resonance mode. J vk

[0032] Advantageously, the Linear Variant Parameter (LPV) controller comprises the following affine state matrices: A0vk) = Ao+ fvk Ai $Qvk) ” 80+ ^(Kk) ~ ?vk Q ^(Çk) ~ fvk Di where Ao, Bo, Co, Do, Ai, Bb Ci, Di denote matrix gains which are the parameters saved in memory of said corrector.

[0033] In another embodiment, the optronic sight further includes means for acquiring the fundamental frequency of vibrational disturbances generated by the operation of at least one device of the sight, the adaptive corrector being configured to receive as input said fundamental frequency of vibrational disturbances and to provide as output a displacement setpoint value to the displacement means from said fundamental frequency and the fundamental frequency of the critical mode.

[0034] In this embodiment, said adaptive controller advantageously follows a state representation according to the following formula: [00351 x M = A(f vt , f m )x k + B(f vie fje t Ut = C' KV J min J vk J max / '. < / < f' J min m J max

[0036] where xk is the state variable of the controller, £k is the input control error of the adaptive controller, uk is the digital control of the means of movement calculated by the adaptive controller, fmin and fmax are two frequencies bounding the fundamental real-time frequency f of the critical mode.

[0037] For a two-parameter LPV-controlled controller, the state matrices (A, B, C, D) are affine in f and f' and can be written in the form: 4^ Z») = -¼+ 7^^ / ^ B(^Â)=«o+Vi + V2 ^ / , / / .)=^ / ,^ / ^- D(f) = D Q + f \J vk J m / o J vk { J m -

[0038] where A0, B0, C0, D0, Al, Bl, Cl, Dl, A2, B2, C2, D2 denote matrix gains which are the parameters saved in memory of a software which implements said adaptive controller K(ff).

[0039] The invention also relates to a motorized device such as an aerial, marine, or land vehicle, comprising an optronic sight as defined above. Brief description of the figures

[0040] Other objects, features and advantages of the invention will become apparent from the following description, given solely by way of non-limiting examples, and made with reference to the accompanying drawings, in which:

[0041] [Fig-1] is a schematic view of an optronic sight according to the prior art;

[0042] [Fig.2] is a diagram representing the operation of an optronic sight according to the prior art;

[0043] [Fig.3] and [Fig.4] are Bode plots illustrating respectively the gain of the mechanical transfer function H cardan, between the useful torque and the gyrometric speed, as a function of frequency, and the gain of the transfer function of a stationary speed controller between the gyrometric speed and the electrical control voltage of the motor, as a function of frequency;

[0044] [Fig.5] is a schematic view of an optronic sight according to the invention;

[0045] [Fig.6] is a diagram representing the operation of an optronic sight according to the invention;

[0046] [Fig.7] is a schematic view of an optronic sight according to another embodiment of the invention;

[0047] [Fig.8] is a diagram representing the operation of the optronic sight of [Fig.7]; and

[0048] [Fig.9] is a diagram illustrating an optronic sight according to yet another embodiment of the invention.

[0049] [Fig. 10] is a diagram illustrating an optronic sight according to yet another embodiment of the invention. Detailed description of the invention

[0050] Reference is made first to figures 5 and 6 which respectively represent an example of an embodiment of an optronic sight and an operating diagram of such a sight according to the invention.

[0051] Such a sight is intended to equip an aerial, marine or land vehicle, for example an aircraft such as a helicopter.

[0052] The optronic sight, designated by the general numerical reference 12, includes in particular:

[0053] a sighting module 13 capable of being moved around a first X axis and a second Y axis, which may be non-perpendicular or perpendicular, respectively horizontal and vertical,

[0054] means for moving the aiming module 13 around the first X axis and the second Y axis, consisting of motors controlled by CI and Cil commands delivered by an adaptive corrector 16, and

[0055] means for continuously measuring 17 an angular data representing the position of the sighting module 13 around the first and second axes, comprising a gyroscope, in the case of an angular position measurement, or a gyrometer, in the case of an angular velocity measurement.

[0056] The measuring means deliver either measurements of angular positions 0X and 0Y of the line of sight Ldv of the sighting module 13, along the X and Y axes, or measurements of angular velocities Qx and QY of the line of sight Ldv, along the X and Y axes.

[0057] As in the prior art, the sighting module 13 is mounted on a support 18 fixed to the air, sea or land vehicle.

[0058] With reference to [Fig.6], the optronic sight 12 includes a servo loop 20 intended to control a position parameter of the sighting module 13, in particular the absolute angular position 0X and 0Y or the absolute angular velocity Qx and Qy of the line of sight Ldv along the X and Y axes on a position setpoint yc.

[0059] This servo loop 20 includes a digital part comprising a comparator 21 ensuring the comparison between the setpoint yck and a sampled measurement ymk of the modeled angular data (position or angular velocity) of the line of sight in order to deliver a servo error 8k to the compensator K).

[0060] The analog part of the servo loop 20 comprises the transfer functions Hmot and Hcardan of the motor and the cardans, respectively, and the function of Hgyro transfer modeling the dynamics of the measurement of the angular measurement data or velocity y of the line of sight.

[0061] As in the embodiment described previously with reference to [Fig.2], the measurement of the modeled angular data of the line of sight ym passes through an analog-to-digital converter (ADC) and is thus sampled to deliver a sampled measurement ymk to the comparator 21.

[0062] Similarly, the transfer function Hmot receives, on the one hand, the analog control voltage u corresponding to a digital control uk delivered by the controller K( f) and then converted by a digital-to-analog converter (DAC) and, on the other hand, J vk part, an analog voltage ue corresponding to the back electromotive force obtained from a back electromotive force constant Ke applied, at the angular velocity Q of the line of sight.

[0063] The electromechanical torque Cmot supplied by the motor actuates the cardans modeled by the transfer function Hcardan in order to compensate or cancel the error 8k due to the disturbing friction torque Cf in the cardan bearings, but also a critical mechanical mode which appears in the transfer function Hcardan.

[0064] The critical mechanical mode is first of all an anti-resonance mode which, as previously indicated with reference to Figures 3 and 4, creates an attenuation in the transfer function of the servo-mechanical system, and in the overall transfer function of the servo-electromechanical system, including cardans and motors.

[0065] However, we do not depart from the scope of the invention when the critical mode is a mechanical resonance mode of the controlled device which leads to an overvoltage in the electromechanical transfer function.

[0066] In the following description, it will be assumed that the servo system ensures compensation of the critical mode of antiresonance.

[0067] As previously stated, the frequency of the critical antiresonance mode varies as a function of the temperature T.

[0068] The compensator K(f) is linear and time-varying. It is configured in such a way as Jvk to dynamically compensate for the anti-resonance mode included in the Hcardan transfer function and which has a fundamental frequency varying over time.

[0069] The control loop 20 thus includes means for determining the fundamental frequency f of the anti-resonance mode, comprising a sensor of temperature 22 and a lookup table 23 in which fundamental frequency values ​​are stored as a function of temperature T. The lookup table 23 therefore receives, as input, a numerical temperature value yk resulting from sampling the measured temperature value T by an analog-to-digital converter (ADC). It delivers, at output, a fundamental frequency f corresponding to the temperature measured by the controller K for J vk deduce a UK digital order.

[0070] From the fundamental frequency thus determined as a function of temperature, the controller is calculated to compensate for the anti-resonance mode. The calculations performed by the adaptive controller advantageously use a Linear Variable Parameter (LPV) control.

[0071] In the case of an LPV-controlled controller, a minimal state representation of the system K(r) is denoted by (A, B, C, D) with A e B?*”, B e R^, C e Rix" and D 7 yk G R. The state-form software implementation of the adaptive controller K( f ) is J vk done according to the following relationship: (Xk+1 = ÂCvk)xk + B(fvk)£k l Llk - C*Qvk)xk + Dpvk)sk ^niin — $vk — ^max where xk e R” is the state variable of the adaptive controller, ek is the input control error of the adaptive controller, uk is the numerical control of the means of movement calculated by the adaptive controller (output of the adaptive controller), fmin and fmax are two frequencies bounding the real-time fundamental frequency f of the J vk resonance mode or anti-resonance.

[0072] For a single-parameter LPV controller, the state matrices (A, B, C, D) are affine in f and can be written in the form: J vk A(Jvk) = A04-fvk Ai B(Jvk) - Sq+ îvk C(fvk) = Co + Kk Ci where A0, B0, C0, D0, Al, Bl, Cl, DI denote matrix gains which are the parameters saved in memory of a software which implements said adaptive controller K( f ). vk

[0073] Figures 7 and 8 show another embodiment of an optronic sight according to the invention.

[0074] In these figures, elements identical to those described previously with reference to figures 5 and 6 are designated by the same numerical references.

[0075] In this embodiment, the means for determining the fundamental frequency of the anti-resonance mode include means 24 for calculating a transfer function g(U,I) between the current I supplying the controlled device, namely the motor 14 or the motor 15, and the digital electrical voltage U generated by the servo controller. The current is, for example, measured using a current sensor 25.

[0076] The back electromotive force feedback causes a disturbance in the overall transfer function, in particular in the transfer function of the motor Hmot, this back electromotive force being related to the angular velocity of the line of sight, introducing an anti-resonance mode in the transfer function.

[0077] The transfer function g(U,I) between the motor supply current and the digital output voltage of the controller thus makes it possible to identify in real time the fundamental frequency fv of the anti-resonance mode, which is provided to the adaptive controller to calculate the control voltage for the motors 14 and 15 driving the movement of the aiming module.

[0078] The frequency of the anti-resonance mode can be identified either by searching for a local minimum on a Fast Fourier Transform (FFT) or Power Spectral Density (PSD) ratio, or by identifying a transfer function via a recursive least squares method whose parameters allow the resonance frequency to be calculated.

[0079] Finally, it should be noted that in the embodiments described above with reference to Figures 5 to 8, the LPV adaptive corrector is single-parameter, in that it is calculated from a fundamental frequency allowing compensation of the anti-resonance mode, said fundamental frequency depending on a parameter such as temperature, in the embodiment of Figures 5 and 6, or as a function of the back electromotive force produced by the controlled device, in the embodiment of Figures 7 and 8, according to the angular position or the speed of movement of the aiming module.

[0080] The corrector can, however, take several parameters into account. It can, in fact, consider the frequency of the mechanical anti-resonance mode, but also other sources of disturbance to the line of sight, whose natural frequency varies. For example, it could be a cooling system integrated into the optical sight designed to cool the sighting module(s) and, in particular, sighting modules that incorporate an infrared optical sensor requiring temperature control.

[0081] A cooling machine generates sinusoidal disturbances whose frequency varies according to the temperature required to cool the sighting module, which itself depends on the temperature of the external environment.

[0082] In the embodiment illustrated in Figures 9 and 10, which correspond respectively to compensation of the disturbances produced by the back electromotive force feedback (Figure 9) and to compensation of the anti-resonance mode whose fundamental frequency varies with temperature (Figure 10), the digital control voltage uk is generated by the controller from the fundamental frequency of the anti-resonance mode f and from the fundamental frequency f J vk J m vibrational disturbances caused by the operation of the device(s) 26 of the viewfinder generating the disturbances

[0083] The frequency of these disturbance sources f and f, which are independent J vk J m and originate from different phenomena and are acquired in parallel by distinct and independent means.

[0084] The fundamental frequency f of the vibration disturbances can be provided via a communication module 27 to the computing means 24 ([Fig.9]) or to the correspondence table 23 ([Fig. 10])

[0085] In the case of a two-parameter LPV-controlled controller, a minimal state representation of the system K( ff ) is designated by (A, B, C, D) with A e Rnxi\ J v]^ J m B e R”*', ​​C g !x" and DG R.. The state-form software implementation of the adaptive controller K( ff ) is done according to the following relationship: Xk+l — + ni) HAS f < f < f J min J vk J max f' < f < f' J min m J max

[0086] where xk g is the state variable of the adaptive controller, Kk is the input control error of the adaptive controller, uk is the numerical control of the means of movement calculated by the adaptive controller (output of the adaptive controller), fmin and fmax are two frequencies bounding the real-time fundamental frequency f of the resonance or anti-resonance mode, f'min and f max are two frequencies J vk limiting the fundamental real-time frequency f of the cold machine.

[0087] For a two-parameter LPV-controlled controller, the state matrices (A, B, C, D) are affine in f and f' and can be written in the form: J vk J m AÏf A ) ^An+fA+f A. \J vk J m / ( ! J vk 1 J m ~ ) =B() + f ,B} + f Bo \J vW J m ) J vk 1 J m o(ff} = D Q + f D2 \J vk' J m} v J vk 1 J mz

[0088] where AO, B0, CO, DO, Al, Bl, Cl, Dl, A2, B2, C2, D2 denote matrix gains which are the parameters saved in memory of a software which implements said adaptive controller K(ff).

[0089] Finally, it should be noted that in the embodiments just described, the viewfinder includes a corrector which is calculated to compensate for the anti-resonance mode of the controlled device.

[0090] As previously stated, the invention also applies to the compensation of a mechanical resonance mode of the controlled device which leads to an overvoltage in the electromechanical transfer function and therefore by integrating an anti-resonance in the servo controller.

[0091] In the case of compensation of a mechanical mode of resonance, a determination of the fundamental frequency of the mode of resonance is similarly made, the corrector being calculated from the fundamental frequency determined to compensate for the mode of resonance.

Claims

Demands

1. Optronic sight for motorized vehicle such as an aerial, marine or land vehicle, comprising: - a sighting module (13) capable of being moved around a first axis (X) and a second axis (Y) not parallel to the first axis; - means (14, 15) for moving the sighting module around the first axis and the second axis; and - a servo loop (20) for controlling a position parameter of the sighting module to a setpoint, comprising an adaptive servo controller (16) capable of calculating a command (CI, Cil) for a controlled device having a critical mode modifying the response of the device, characterized in that it comprises means (22, 23; 24, 25) capable of determining a fundamental frequency (f) of the critical mode variable as a function of a parameter Jvk of the operation of the controlled device, the controller being calculated from the fundamental frequency determined to compensate for the critical mode.

2. Optronic sight according to claim 1, wherein the fundamental frequency of the critical mode is variable as a function of temperature, the means for determining a fundamental frequency of the critical mode comprising a temperature sensor (22) and a lookup table (23) between temperature values ​​and fundamental frequency values.

3. Optronic sight according to claim 1, wherein the fundamental frequency (f) of the critical mode is estimated via the back electromotive force produced by the controlled device, as a function of a data representing the angular velocity of the sighting module, means for determining a fundamental frequency of the critical mode comprising means (24) for calculating a transfer function between the current supplying the controlled device and an output voltage of the corrector.

4. Optronic sight according to any one of claims 1 to 3, wherein the critical mode modifying the response of the device is a mechanical anti-resonance mode.

5. Optronic sight according to any one of claims 1 to 3, wherein the critical mode modifying the response of the device is a resonant mechanical mode.

6. Optronic sight according to any one of claims 1 to 5, wherein the servo-controlled position parameter of the sighting module is the angular position of the sighting module (13).

7. Optronic sight according to any one of claims 1 to 5, wherein the servo-controlled position parameter of the sighting module is the speed of movement of the sighting module (13).

8. Optronic sight according to any one of claims 1 to 7, wherein the adaptive controller comprises a Linear Variable Parameter (LPV) controller. 9 Optronic sight according to claim 8, wherein said adaptive controller (16) follows a state representation according to the following formula: (xk+i = APvk)xk + B(fvk)Ek t Bk — + ^(fvk)Ek fmin — ^vk — where xk is the state variable of the controller, is the input servo error of the adaptive controller (16), uk is the numerical control of the movement means calculated by the adaptive controller (16), fmin and fmax are two frequencies bounding the fundamental real-time frequency f of the critical mode. J vk 10.An optronic sight according to claim 8 or 9, wherein said Linear Variable Parameter (LPV) corrector comprises the following affine state matrices: A(vk) = Ao + L At B(vk) C(LkJ “ L k QD(U) = Do + fïk Dx where Ao, Bo, Co, Do, Ai, Bi, Ci, Di denote matrix gains which are the parameters stored in memory of said corrector.

11. An optronic sight according to any one of claims 1 to 8, further comprising means for acquiring the frequency. fundamental frequency of vibrational disturbances generated by the operation of at least one device (26) of the viewfinder, the adaptive corrector being configured to receive as input said fundamental frequency of the vibrational disturbances (f) and provide as output •' m a setpoint value for displacement to the means of displacement from said fundamental frequency of the vibration disturbances and the fundamental frequency of the critical mode (f). J m 12. Optronic sight according to claim 11, wherein said adaptive corrector (16) follows a state representation according to the following formula: Xk+1 “ fm)Xk + ^[fy^ fm)£k min J vk J nuix f' <f<f' J min J m J max where xk is the state variable of the controller, is the input control error of the adaptive controller (16), uk is the digital control of the means of movement calculated by the adaptive controller (16), fmin and fmax are two frequencies bounding the fundamental real-time frequency f of the critical mode. J vk 13. Optronic sight according to claim 12, wherein said Linear Variable Parameter (LPV) corrector comprises the following affine state matrices B(ff) = B0 + f . B^ + f B^ \J vk J ni / u J vk J ni ~ where Ao, Bo, Co, Do, Ai, Bi, Ci, Di A2, B2, C2, D2 denote matrix gains which are the parameters saved in memory of said corrector.

14. Motorized device such as an aerial, marine or land vehicle, comprising an optronic sight according to any one of claims 1 to 13.

Images