Circuit, system and method for the camera motor limit system of an airborne optoelectronic pod

Abstract

The present invention relates to the technical field of on-board optoelectronic pod camera motor limit protection, and specifically relates to a circuit, a system and a method for an on-board optoelectronic pod camera motor limit system; the circuit for the on-board optoelectronic pod camera motor limit system includes: a main controller; a positive AND gate unit connected to the positive-phase PWM output terminal and the positive-phase Hall unit output terminal of the main controller; a negative AND gate unit connected to the negative-phase PWM output terminal and the negative-phase Hall unit output terminal of the main controller; a decoding unit connected to the output terminals of the positive AND gate unit and the negative AND gate unit; and a DC motor drive unit connected to the two output terminals of the decoding unit. The technical solution of the present invention can protect the motor against electrical limit in the event of the main controller crashing, brake the moving part of the motor at the electrical limit, and prevent it from causing collision damage.

Description

Technical Field

[0001] The present invention relates to the technical field of airborne optoelectronic pod camera motor limit protection, and specifically relates to a circuit, a system and a method for an airborne optoelectronic pod camera motor limit system. Background Art

[0002] In motor control devices, the protection of the limit position is a crucial component. The traditional limit protection measures mainly include three types: mechanical limit, electrical limit, and software limit. Among them, 1. Mechanical limit: By means such as hardware structure collision, blocking the moving part to stop the motor; 2. Electrical limit: Feedback the limit information of the moving position through devices such as Hall elements, travel switches, and photoelectric switches, and control the motor to stop rotating through a single-chip microcomputer; 3. Software limit: Read the position information such as the potentiometer value or encoder value through a single-chip microcomputer, feedback the position limit information according to the previous calibration information, and control the motor to stop rotating after completing the information comparison. In the existing technical solutions, generally, these three measures are combined with each other. However, once the single-chip microcomputer crashes, both the electrical limit control and the software limit control will fail, and the motor can only be stopped by the collision of the mechanical limit, which will cause irreversible damage to the entire system. Therefore, in the prior art, an independent single-chip microcomputer or an FPGA programmable logic chip is added for improvement, but such circuits usually have low stability, complex logic structures, and high costs. Therefore, such solutions are not very suitable for high-performance cameras of airborne optoelectronic pods.

[0003] It should be noted that high-performance cameras belong to the category of precision instruments. Once the single-chip microcomputer crashes and the moving parts collide at the mechanical limit, the following three main hidden dangers will occur: 1. The collision loss of expensive equipment. Components such as infrared detection cores and lenses are expensive and fragile at the same time. Therefore, excessive collisions will be transmitted to the core and lenses, seriously affecting their service life; 2. Affecting the optical axis consistency of the optical load equipment of the airborne optoelectronic pod. The airborne optoelectronic pod contains different load detectors such as mid-wave infrared, short-wave infrared, near-infrared, visible light, and lasers. Before the whole machine is jointly debugged and tested, relatively complex optical axis consistency calibration is required. Excessive limit mechanical collisions of different loads will cause the visual axis centers of each load to deviate from the original position, making the equipment lose optical axis consistency and requiring re-calibration; 3. After stopping at the mechanical structure position, the rotational torque of the motor always exists, that is, it is blocked in the mechanical structure part for a long time, which is easy to burn out the motor.

[0004] Based on this, those skilled in the art urgently need a brand-new, simpler, more stable and lower-power motor limit protection measure to be suitable for airborne optoelectronic pod cameras. Summary of the Invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defects existing in the above-mentioned prior art, so as to provide a circuit, a system and a method for the camera motor limit system of an airborne optoelectronic pod.

[0006] A circuit for the camera motor limit system of an airborne optoelectronic pod, comprising:

[0007] A main controller;

[0008] A positive AND gate unit connected to the positive-phase PWM output terminal and the positive-phase Hall unit output terminal of the main controller;

[0009] A negative AND gate unit connected to the negative-phase PWM output terminal and the negative-phase Hall unit output terminal of the main controller;

[0010] A decoding unit connected to the output terminals of the positive AND gate unit and the negative AND gate unit;

[0011] And a DC motor drive unit connected to the two output terminals of the decoding unit.

[0012] Preferably, it further comprises: a positive-phase comparison unit, a positive-phase voltage-dividing unit, a negative-phase comparison unit and a negative-phase voltage-dividing unit;

[0013] The positive-phase Hall unit, the positive-phase comparison unit, the positive-phase voltage-dividing unit and the positive AND gate unit are sequentially connected by signals;

[0014] The negative-phase Hall unit, the negative-phase comparison unit, the negative-phase voltage-dividing unit and the negative AND gate unit are sequentially connected by signals.

[0015] Preferably, the positive-phase voltage-dividing unit and the negative-phase voltage-dividing unit have the same circuit structure;

[0016] The positive-phase voltage-dividing unit is composed of a first resistor and a second resistor;

[0017] The 5V voltage output terminal of the positive-phase comparison unit is connected in series with the first resistor and the second resistor to ground;

[0018] The positive AND gate unit connected to the 3.3V voltage and the main controller are connected in parallel and then connected in series with the second resistor to ground.

[0019] A limit system for the camera motor of an airborne optoelectronic pod, comprising the circuit for the camera motor limit system of an airborne optoelectronic pod, and further comprising:

[0020] A power supply unit, an industrial computer, a serial port unit, a lens potentiometer, a motor and a mid-wave infrared lens;

[0021] The power supply unit is respectively connected for power supply to the serial port unit, the positive AND gate unit, the negative AND gate unit, the decoding unit, the DC motor drive unit, the positive-phase comparison unit, the negative-phase comparison unit, the lens potentiometer, the positive-phase Hall unit and the negative-phase Hall unit;

[0022] The industrial control computer is connected to the main controller through the serial port unit;

[0023] The output end of the lens potentiometer is connected to the main controller;

[0024] The positive-phase motor output control terminal and the negative-phase motor output control terminal of the DC motor drive unit are both connected to the motor;

[0025] The positive-phase motor control terminal and the negative-phase motor control terminal of the motor are connected to the mid-wave infrared lens.

[0026] Preferably, the industrial control computer is connected to the main controller through the serial port unit. Specifically:

[0027] The industrial control computer is connected to the serial port unit through the first full-duplex wiring;

[0028] The serial port unit is connected to the main controller through the second full-duplex wiring.

[0029] A limiting method for the motor of an airborne optoelectronic pod camera, implemented based on a limiting system for the motor of an airborne optoelectronic pod camera, includes:

[0030] Applying to the braking limit process when the main controller is down:

[0031] When the main controller is down: both the positive-phase PWM signal and the negative-phase PWM signal of the main controller are output:

[0032] Respectively and in real time obtain the limit signal from the positive-phase Hall unit and the negative-phase Hall unit, and obtain the PWM signal from the main controller;

[0033] When the positive-phase limit signal is high level and the negative-phase limit signal is low level, the positive-phase AND gate unit and the negative-phase AND gate unit jointly control the motor to rotate forward to break away from the negative-phase limit position until the positive-phase limit position signal is high level and the negative-phase limit signal is high level; the positive-phase AND gate unit outputs high level based on the AND gate logic, the decoding unit outputs high level, and the DC motor drive unit outputs low level to control the motor to be in the braking state;

[0034] When the negative-phase limit signal is high level and the positive-phase limit signal is low level, control the motor to rotate in reverse to break away from the positive-phase limit position; until the negative-phase limit position signal is high level and the positive-phase limit signal is high level; the negative-phase AND gate unit outputs high level based on the AND gate logic, the decoding unit outputs high level, and the DC motor drive unit outputs low level to control the motor to be in the braking state.

[0035] Preferably, it further includes the process applied when the main controller is in the limit protection state:

[0036] When the main controller is in the limit protection state: the mid-wave infrared lens is at the limit position and the motor is in the protection state; among them, the mid-wave infrared lens being at the limit position is specifically manifested as: at the same moment, only one of the inverted PWM signal and the inverted limit signal is at a high level, and only one of the non-inverted PWM signal and the non-inverted limit signal is at a high level;

[0037] Obtain the limit signal from the non-inverted Hall unit and the inverted Hall unit in real time respectively, and obtain the PWM signal from the main controller;

[0038] The main controller outputs the PWM signal of the corresponding phase to the corresponding AND gate unit. The corresponding AND gate unit outputs a low level based on the AND gate logic. The decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state.

[0039] Preferably, it also includes the process applied when both the motor and the main controller are in the normal state:

[0040] When both the motor and the main controller are in the normal state, there are two cases: one is that only one of the non-inverted AND gate unit and the inverted AND gate unit outputs a high level, and the other is that both the non-inverted AND gate unit and the inverted AND gate unit output low levels;

[0041] When only the non-inverted AND gate unit outputs a high level, the non-inverted output terminal of the decoding unit outputs a high level, the inverted output terminal outputs a low level, the non-inverted output terminal of the DC motor drive unit outputs a high level, and the inverted output terminal outputs a low level to control the motor to rotate forward;

[0042] When only the inverted AND gate unit outputs a high level, the inverted output terminal of the decoding unit outputs a high level, the non-inverted output terminal outputs a low level, the inverted output terminal of the DC motor drive unit outputs a high level, and the non-inverted output terminal outputs a low level to control the motor to rotate in reverse;

[0043] When both the non-inverted AND gate unit and the inverted AND gate unit output low levels, the decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state.

[0044] The technical solution of the present invention has the following advantages:

[0045] The technical solution of the present invention can protect the motor against electrical limit when the main controller fails, brake the moving part of the motor at the electrical limit, and prevent it from causing collision damage. In the present invention, by using components such as a comparator chip, an AND gate chip, a decoder chip, and a DC motor drive chip, a combinational logic circuit module is formed, so that the braking ability at the limit is independent of the main controller, and thus the DC motor can be actively braked at the limit position. And even when the main controller has problems during the operation of the motor at non-limit positions, the motor can be finally converted to the braking state by using the combinational logic circuit control, and a stable control closed-loop can be achieved to prevent the structural part from causing collision damage. Description of the Drawings

[0046] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0047] Figure 1 It is the circuit schematic diagram of the motor limit system for the airborne optoelectronic pod camera of the present invention;

[0048] Figure 2 It is the principle block diagram of the positive-phase voltage-dividing unit;

[0049] Figure 3 It is the schematic diagram of the limit system for the airborne optoelectronic pod camera motor of the present invention;

[0050] Figure 4 It is the method flow chart of Embodiment 4 of the present invention. Detailed Embodiments

[0051] The following will clearly and completely describe the technical solutions of the present invention with reference to the drawings. Obviously, the described embodiments are some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0052] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0053] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "mounted", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0055] Embodiment 1

[0056] Such as Figure 1 This embodiment discloses a circuit for the camera motor limit system of an airborne optoelectronic pod, including:

[0057] A main controller;

[0058] A positive AND gate unit connected to the positive PWM output terminal and the positive Hall unit output terminal of the main controller;

[0059] A negative AND gate unit connected to the negative PWM output terminal and the negative Hall unit output terminal of the main controller;

[0060] A decoding unit connected to the output terminals of the positive AND gate unit and the negative AND gate unit;

[0061] And a DC motor drive unit connected to the two output terminals of the decoding unit.

[0062] It also includes: a positive comparison unit, a positive voltage dividing unit, a negative comparison unit, and a negative voltage dividing unit;

[0063] The positive Hall unit, the positive comparison unit, the positive voltage dividing unit, and the positive AND gate unit are sequentially connected by signals;

[0064] The negative Hall unit, the negative comparison unit, the negative voltage dividing unit, and the negative AND gate unit are sequentially connected by signals.

[0065] Among them, the positive-phase voltage-dividing unit and the negative-phase voltage-dividing unit have the same circuit structure;

[0066] Such as Figure 2 The positive-phase voltage-dividing unit is composed of a first resistor and a second resistor;

[0067] The 5V voltage output terminal of the positive-phase comparison unit is connected in series with the first resistor and the second resistor to ground;

[0068] The positive-phase AND gate unit connected to the 3.3V voltage and the main controller are connected in parallel and then connected in series with the second resistor to ground.

[0069] The negative-phase voltage-dividing unit is composed of a third resistor and a fourth resistor;

[0070] The 5V voltage output terminal of the negative-phase comparison unit is connected in series with the third resistor and the fourth resistor to ground;

[0071] The negative-phase AND gate unit connected to the 3.3V voltage and the main controller are connected in parallel and then connected in series with the fourth resistor to ground.

[0072] In this embodiment, the resistance values of the first resistor and the third resistor are both 5.2KΩ; the resistance values of the second resistor and the fourth resistor are both 10KΩ.

[0073] Embodiment 2

[0074] On the basis of Embodiment 1, this embodiment further discloses a limit system for the camera motor of an airborne optoelectronic pod, including a circuit for the limit system of the camera motor of the airborne optoelectronic pod, and further including:

[0075] A power supply unit, an industrial computer, a serial port unit, a lens potentiometer, a motor, and a medium-wave infrared lens;

[0076] The power supply unit is respectively connected for power supply to the serial port unit, the positive-phase AND gate unit, the negative-phase AND gate unit, the decoding unit, the DC motor drive unit, the positive-phase comparison unit, the negative-phase comparison unit, the lens potentiometer, the positive-phase Hall unit, and the negative-phase Hall unit;

[0077] The industrial computer is connected to the main controller through the serial port unit; specifically: the industrial computer is connected to the serial port unit through a first full-duplex connection; the serial port unit is connected to the main controller through a second full-duplex connection. In this embodiment, the first full-duplex connection and the second full-duplex connection use the model RS422.

[0078] The output terminal of the lens potentiometer is connected to the main controller;

[0079] The positive-phase motor output control terminal and the negative-phase motor output control terminal of the DC motor drive unit are both connected to the motor;

[0080] The positive-phase motor control terminal and the reverse-phase motor control terminal of the motor are connected to the mid-wave infrared lens.

[0081] The parameters and models of the specific components of this system are as follows. Figure 3 The overall block diagram of this system for connecting to the circuit board in combination with the specific component parameters and models is as follows:

[0082] 1) Power supply unit: A DC regulated power supply is adopted: 220V to 32V 6A, providing a 12V voltage input for the entire system; it also includes a power management module: mainly including a DC-DC part and an LDO part. In the DC-DC part, the RM9131E chip converts the 12V power input into a 5V power output, and then in the LDO part, the RY1117 converts the 5V power input into a 3.3V power output.

[0083] 2) Industrial computer: Provides motor drive instruction input and status feedback display.

[0084] 3) Main controller: The ARM control chip CS32F405RGT6 is adopted: 1. Receives and parses the instructions of the industrial computer, 2. Provides the control logic for the motor drive unit, 3. Reads the limit signal, 4. Reads the value of the lens potentiometer that displays the motor motion state; 5. Reports the system status.

[0085] 4) Positive-phase Hall unit and reverse-phase Hall unit: Both adopt Hall elements: YS1138 unipolar Hall effect sensors, with a working voltage of 3.8V to 40V, a sampling period of 50ms, an operating point standard Gaussian value of 250Gauss, a release point standard Gaussian value of 200Gauss, a hysteresis of 50Gauss, and a working temperature of 40°C to 150°C. They are motion module detection units, fixedly installed at the two limits of the mid-wave infrared lens to judge whether the mid-wave infrared lens motion reaches the limit.

[0086] 5) Positive-phase comparison unit and reverse-phase comparison unit: The comparator chip AIP74HC85 is adopted: When the two Hall units detect the limit, the sampling period of the Hall element is relatively long at 50ms, so the comparator is used to shorten the time to 0.5ms to improve the timeliness of the subsequent system judgment.

[0087] 6) Positive-phase voltage division unit and reverse-phase voltage division unit: Since the levels output by the positive-phase comparison unit and the reverse-phase comparison unit are 5V, the principle of resistor series voltage division is used here to convert the level to 3.29V, and the module implementation is as Figure 2 shown.

[0088] 7) Positive AND gate unit and negative AND gate unit: Both use the AND gate chip AIP74LVC08. In the AND gate logic chip, the limit detection result is logically ANDed with the PWM output of the main controller. When the mid-wave infrared lens reaches the limit position, the limit information fed back by the corresponding Hall element is at a low level, and the output of the corresponding comparator is also at a low level. At this time, no matter what level the PWM output of the main controller is, the output of the corresponding AND gate unit is at a low level, and no output is provided for the subsequent drive. Even if the main controller is in a downtime state, the motor is still in a protected state at the limit.

[0089] 8) Motor: Use the DC motor WKX-CCTS-004, which is a brushed cup planetary reduction motor with a rated voltage of DC: 12.0 V and a rated current of 69 mA.

[0090] 9) DC motor drive unit: Use the DC motor drive chip RYH8870, which includes two H-bridge drive circuits for realizing the forward and reverse drive of the DC motor in this embodiment. The input level of the logic terminal is 0~5V, the drive terminal level is 6~45V, and the maximum drive current is 3.6A, meeting the drive ability of the DC motor in this system.

[0091] 10) Decoding unit: Use the decoder chip AIP74LVC139, which is introduced to cooperate with the DC motor drive chip RYH8870.

[0092] Embodiment 3

[0093] To fully introduce the method of this embodiment, the following content will be disclosed before introducing the method of this embodiment.

[0094] Table 1 DC motor drive unit control logic table

[0095]

[0096] According to Table 1, three modes of motor movement are designed: forward rotation, reverse rotation, and braking. At the same time, try to avoid the sliding state, that is, IN1 = 0 and IN2 = 0 do not appear in the input.

[0097] Table 2 Decoding unit control logic table

[0098]

[0099] Table 3 Motor drive logic table

[0100]

[0101] In Table 3, it can be decomposed into 5 cases.

[0102] a) Serial numbers 1, 3, 9, and 11 mean that the mid-wave infrared lens is at both the positive and negative ends of the limit position simultaneously, and this state does not exist;

[0103] b) Serial numbers 7 and 10 mean that the mid-wave infrared lens is in the limit position and the motor is in the protection state. Even if there is a PWM output in the corresponding direction, the motor is still in the braking state at this time;

[0104] c) Serial numbers 12, 15, and 16 are the abnormal states of the main controller:

[0105] d) The states of the remaining serial numbers are the normal states of the motor operation, supporting the forward, reverse, and braking states of the motor;

[0106] e) When traversing the 16 states, the input of the mid-wave infrared lens will not show the unstable sliding state of the DC motor drive chip RYH8870.

[0107] This embodiment discloses a limiting method for the motor of an airborne optoelectronic pod camera based on the limiting system for the motor of an airborne optoelectronic pod camera on the basis of Embodiment 2, including:

[0108] The braking limit process applied when the main controller is down: Specifically adapted to the situations of serial numbers 12, 15, and 16;

[0109] When the main controller is down: Both the forward PWM signal and the reverse PWM signal of the main controller are output:

[0110] The limit signals are respectively obtained from the forward Hall unit and the reverse Hall unit in real time, and the PWM signal is obtained from the main controller;

[0111] When the forward limit signal is at a high level and the reverse limit signal is at a low level, the forward AND gate unit and the reverse AND gate unit jointly control the motor to rotate forward to break away from the reverse limit position until the forward limit position signal is at a high level and the reverse limit signal is at a high level; The forward AND gate unit outputs a high level based on the AND gate logic, the decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state;

[0112] When the reverse limit signal is at a high level and the forward limit signal is at a low level, the motor is controlled to rotate in reverse to break away from the forward limit position; until the reverse limit position signal is at a high level and the forward limit signal is at a high level; The reverse AND gate unit outputs a high level based on the AND gate logic, the decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state.

[0113] It also includes the process applied when the main controller is in the limit protection state: Specifically adapted to the situations of serial numbers 7 and 10;

[0114] When the main controller is in the limit protection state: the mid-wave infrared lens is at the limit position and the motor is in the protection state; among them, the mid-wave infrared lens being at the limit position is specifically manifested as: at the same moment, only one of the inverted PWM signal and the inverted limit signal is at a high level, and only one of the forward PWM signal and the forward limit signal is at a high level;

[0115] Obtain the limit signal from the forward Hall unit and the inverted Hall unit in real time respectively, and obtain the PWM signal from the main controller;

[0116] The main controller outputs the PWM signal of the corresponding phase to the corresponding AND gate unit. The corresponding AND gate unit outputs a low level based on the AND gate logic, the decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state.

[0117] It also includes the process applied when both the motor and the main controller are in the normal state: adapting to the situations corresponding to the remaining serial numbers in d);

[0118] When both the motor and the main controller are in the normal state, there are two situations: one is that only one of the forward AND gate unit and the inverted AND gate unit outputs a high level, and the other is that both the forward AND gate unit and the inverted AND gate unit output low levels;

[0119] When only the forward AND gate unit outputs a high level, the forward output terminal of the decoding unit outputs a high level, the inverted output terminal outputs a low level, the forward output terminal of the DC motor drive unit outputs a high level, and the reverse output terminal outputs a low level to control the motor to rotate forward;

[0120] When only the inverted AND gate unit outputs a high level, the inverted output terminal of the decoding unit outputs a high level, the forward output terminal outputs a low level, the inverted output terminal of the DC motor drive unit outputs a high level, and the forward output terminal outputs a low level to control the motor to rotate in reverse;

[0121] When both the forward AND gate unit and the inverted AND gate unit output low levels, the decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state.

[0122] Embodiment 4

[0123] Based on Embodiments 2 and 3, this embodiment also discloses a method for verifying whether braking is performed by using a lens potentiometer when the main controller crashes, including the following steps:

[0124] It should be noted that to cooperate with the implementation of the DC motor limit protection function of the system in Embodiment 2, taking the focusing group lens in the mid-wave infrared lens as an example, a detailed implementation plan and specific working process are given here. The process steps are as Figure 4 shown, and the steps work as follows:

[0125] Step 1, the operator operates the host computer software of the industrial control computer and sends a serial port command for the mid-wave infrared focusing lens group to move towards the positive limit position;

[0126] Step 2, the main controller receives and parses the information in the serial port command;

[0127] Step 3, after the main controller obtains the positive-phase movement command of the mid-wave infrared lens, it performs the following actions;

[0128] Step 3.1, the main controller outputs a control command: set the first channel of the timer to output a corresponding positive PWM signal, with a period of 1 ms, a frequency of 1 kHz, and a duty cycle of 100%. The second channel of the timer outputs a reverse PWM signal with a duty cycle of 0, so that the motor receiving the control command starts to rotate forward and pushes the focusing lens group towards the positive limit position through the guide rail;

[0129] Step 3.2, the main controller reports the movement state of the focusing lens group, the potentiometer value of the position where the focusing lens group is located, and the limit state to the industrial control computer through the serial port unit;

[0130] Step 4, during the rotation of the motor, the main controller continuously detects the limit signal and collects the lens potentiometer value;

[0131] Step 5, when the main controller detects that the positive limit signal is zero, it indicates that at this moment, the lens has moved to the positive limit position; simulate the main controller being in a crashed state: make this main controller not make adjustments, observe whether the motor brakes, whether it stays at the mechanical limit or the electrical limit, and at the same time report the lens potentiometer information;

[0132] Step 6, feedback to the industrial control computer that the mid-wave infrared lens has moved to the positive electrical limit position and whether the potentiometer value has changed;

[0133] Step 6.1 The motor movement stops, and information that the lens potentiometer value does not change is reported;

[0134] Step 6.2 The motor does not stop moving, and information that the lens potentiometer value changes is reported.

[0135] Through Steps 1 to 6, in this embodiment, according to the host computer command, the focusing lens in the mid-wave infrared lens assembly is moved to the positive limit position, and at the positive limit position, the crashed state of the main controller motor is simulated; the result shows that the focusing lens can stably stop at the corresponding electrical limit. At the same time, during the reverse movement of the focusing lens group, the operation process is similar, only the duty cycles of the two-way PWM signal outputs need to be swapped.

[0136] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or alterations can be made based on the above description. It is not necessary and impossible to list all implementation manners here. And the obvious changes or alterations derived therefrom still fall within the protection scope of the present invention.

Claims

1. The circuit for the camera motor limit system of the airborne optoelectronic pod, characterized in that, Comprising: A main controller; A positive AND gate unit connected to the positive PWM output terminal of the main controller and the output terminal of the positive Hall unit; A negative AND gate unit connected to the negative PWM output terminal of the main controller and the output terminal of the negative Hall unit; A decoding unit connected to the output terminal of the positive AND gate unit and the output terminal of the negative AND gate unit; And a DC motor drive unit connected to the two output terminals of the decoding unit; Among them, applied to the braking limit process when the main controller is down: When the main controller is down: both the positive PWM signal and the negative PWM signal of the main controller are output: The limit signals are respectively and real-time obtained from the positive Hall unit and the negative Hall unit, and the PWM signal is obtained from the main controller; When the positive limit signal is high level and the negative limit signal is low level, the positive AND gate unit and the negative AND gate unit jointly control the motor to rotate forward to break away from the negative limit position until the positive limit position signal is high level and the negative limit signal is high level; the positive AND gate unit outputs high level based on the AND gate logic, the decoding unit outputs high level, and the DC motor drive unit outputs low level to control the motor to be in the braking state; When the negative limit signal is high level and the positive limit signal is low level, control the motor to rotate in reverse to break away from the positive limit position until the negative limit position signal is high level and the positive limit signal is high level; the negative AND gate unit outputs high level based on the AND gate logic, the decoding unit outputs high level, and the DC motor drive unit outputs low level to control the motor to be in the braking state.

2. The circuit for the camera motor limit system of the airborne optoelectronic pod according to claim 1, characterized in that, It further comprises: A positive comparison unit, a positive voltage dividing unit, a negative comparison unit and a negative voltage dividing unit; The positive Hall unit, the positive comparison unit, the positive voltage dividing unit and the positive AND gate unit are sequentially connected by signals; The negative Hall unit, the negative comparison unit, the negative voltage dividing unit and the negative AND gate unit are sequentially connected by signals.

3. The circuit for the camera motor limit system of the airborne optoelectronic pod according to claim 2, wherein The circuit structures of the positive voltage dividing unit and the negative voltage dividing unit are the same; The positive voltage dividing unit is composed of a first resistor and a second resistor; The 5V voltage output terminal of the positive comparison unit is connected in series with the first resistor and the second resistor to ground; The positive AND gate unit and the main controller connected to the 3.3V voltage are connected in parallel and then connected in series with the second resistor to ground.

4. A limit system for the camera motor of an airborne optoelectronic pod, characterized in that, Including the circuit for the camera motor limit system of the airborne optoelectronic pod described in claim 3, it further comprises: A power supply unit, an industrial control computer, a serial port unit, a lens potentiometer, a motor and a mid-wave infrared lens; The power supply unit is respectively connected for power supply to the serial port unit, the positive AND gate unit, the negative AND gate unit, the decoding unit, the DC motor drive unit, the positive comparison unit, the negative comparison unit, the lens potentiometer, the positive Hall unit and the negative Hall unit; The industrial control computer is connected to the main controller through the serial port unit; The output terminal of the lens potentiometer is connected to the main controller; Both the positive motor output control terminal and the negative motor output control terminal of the DC motor drive unit are connected to the motor; The positive motor control terminal and the negative motor control terminal of the motor are connected to the mid-wave infrared lens.

5. The limit system for the camera motor of an airborne optoelectronic pod according to claim 4, wherein The industrial control computer is connected to the main controller through the serial port unit. Specifically: The industrial control computer is connected to the serial port unit through a first full-duplex wiring; The serial port unit is connected to the main controller through a second full-duplex wiring.

6. A method for limiting the position of a camera motor in an airborne optoelectronic pod, characterized in that, Implementation of the limit system for the camera motor of an airborne optoelectronic pod based on claim 5, including: applying the braking limit process when the main controller is down; also including the process when the main controller is in the limit protection state: When the main controller is in the limit protection state: the mid-wave infrared lens is at the limit position and the motor is in the protection state; among them, the mid-wave infrared lens being at the limit position is specifically manifested as: at the same moment, only one of the inverted PWM signal and the inverted limit signal is high level, and only one of the non-inverted PWM signal and the non-inverted limit signal is high level; Obtain the limit signal from the non-inverted Hall unit and the inverted Hall unit in real time respectively, and obtain the PWM signal from the main controller; The main controller outputs the PWM signal corresponding to the phase to the corresponding AND gate unit, the corresponding AND gate unit outputs a low level based on the AND gate logic, the decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state.

7. The limiting method for the camera motor of an airborne optoelectronic pod according to claim 6, characterized in that Also including the process when both the motor and the main controller are in the normal state: When both the motor and the main controller are in the normal state, there are two situations: one is that only one of the non-inverted AND gate unit and the inverted AND gate unit outputs a high level, and the other is that both the non-inverted AND gate unit and the inverted AND gate unit output low levels; When only the non-inverted AND gate unit outputs a high level, the non-inverted output terminal of the decoding unit outputs a high level, the inverted output terminal outputs a low level, the non-inverted output terminal of the DC motor drive unit outputs a high level, and the inverted output terminal outputs a low level to control the motor to rotate forward; When only the inverted AND gate unit outputs a high level, the inverted output terminal of the decoding unit outputs a high level, the non-inverted output terminal outputs a low level, the inverted output terminal of the DC motor drive unit outputs a high level, and the non-inverted output terminal outputs a low level to control the motor to rotate in reverse; When both the non-inverted AND gate unit and the inverted AND gate unit output low levels, the decoding unit outputs a high level, and the DC motor drive unit outputs a low level to control the motor to be in the braking state.

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