Front wheel steering engine redundancy control system and method for unmanned aerial vehicle

Abstract

The invention aims to solve the technical problems of insufficient redundant architecture design, low fault diagnosis and switching efficiency and low system integration in the prior art, and provides a front wheel steering engine redundancy control system and method for an unmanned aerial vehicle. A double-ARM architecture cooperative control strategy is adopted, redundant fault-tolerant control of a mechanical coupling single-shaft driving system is achieved, two ARM chips independently drive two motors respectively, the motors are meshed through precision gears to form a mechanical coupling output structure used for driving a corresponding gear set, the gear set is in transmission connection with a gear mechanism, and the gear mechanism is in transmission connection with the gear mechanism. The steering wheel is matched with a nose landing gear of the unmanned aerial vehicle to realize steering; and each ARM chip is provided with a CAN port and an RS485 communication serial port and establishes a parallel data receiving mechanism.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of unmanned aerial vehicle front wheel steering rudder control technology, specifically relates to a kind of unmanned aerial vehicle front wheel steering rudder redundancy control system and method. BACKGROUND

[0002] With the application of unmanned aerial vehicle in logistics transportation, agricultural plant protection and emergency rescue and other fields more and more scale, the reliability of unmanned aerial vehicle ground sliding and steering ability becomes the key technical bottleneck restricting the safety of unmanned aerial vehicle application.The existing unmanned aerial vehicle front wheel steering system usually adopts single rudder drive architecture, single rudder drive architecture exists the risk of single point failure, once when the rudder occurs mechanical jam, circuit failure or communication interruption, it will directly lead to the loss of steering function of unmanned aerial vehicle, and cause the deviation of unmanned aerial vehicle sliding trajectory even the unmanned aerial vehicle rollover accident.

[0003] Therefore, the prior art improves reliability by constructing mechanical redundancy backup system or optimizing the control algorithm of the system, but still has the following technical defects: ① the redundancy architecture design is insufficient, and the key components lack effective backup mechanism; ② the fault diagnosis response is slow, which causes system switching delay and cannot realize fast fault tolerance; ③ the system integration is low, and the compatibility of each component is limited. SUMMARY

[0004] The purpose of the present application is to solve the technical problems of the prior art, such as insufficient redundancy architecture design, low efficiency of fault diagnosis and switching, and low system integration, and to provide a kind of unmanned aerial vehicle front wheel steering rudder redundancy control system and method.

[0005] To achieve the above purpose, the technical solutions provided by the present application are as follows:

[0006] A kind of unmanned aerial vehicle front wheel steering rudder redundancy control system and method, which is characterized by comprising:

[0007] Two control units with the same structure, a transmission module and three position sensors;

[0008] The control unit includes a power module and a communication module, a turning control module, a turning drive module and a motor connected in sequence; the turning control modules of the two control units are connected by cross-processor communication, for realizing real-time sharing of information between them and cooperative control of the turning drive module;

[0009] The turning control module receives external control instructions through the communication module and generates turning control signals; the turning drive module is used to generate driving voltage according to the received turning control signals to drive the corresponding motor to work; the power module is used to power the corresponding turning control module and turning drive module;

[0010] The transmission module comprises a gear set and a gear mechanism, the gear set comprises a gear and two input gear shafts in meshing transmission with the gear, the output ends of the two motors are connected with the input gear shafts respectively for jointly driving the gear to work, and the gear is in transmission connection with the gear mechanism for realizing a steering action in cooperation with the front landing gear of the unmanned aerial vehicle.

[0011] One of the three position sensors is a first position sensor, the first position sensor is installed on the gear of the gear set, and the output end thereof is connected to two turning control modules through a double-channel acquisition architecture; the other two position sensors are a second position sensor and a third position sensor, the second position sensor and the third position sensor are installed on the two input gear shafts of the gear set respectively, and the output ends thereof are connected to the two turning control modules respectively; the three position sensors are used for acquiring position feedback signals of the gear and the input gear shafts.

[0012] Further, the turning control module comprises an ARM chip, an AD sampling expansion chip, a FLASH chip, a Hall signal detection circuit, a commutation logic circuit, an isolation circuit, a buffer circuit, a position detection circuit, a bus voltage phase current detection circuit and a signal conditioning circuit.

[0013] The control signal output end of the ARM chip is connected to the buffer circuit, the commutation logic circuit and the isolation circuit in sequence, the output end of the isolation circuit is connected to the input end of the turning drive module, the feedback input end of the commutation logic circuit is connected to the Hall signal detection circuit, the input end of the Hall signal detection circuit is connected to the rotor end of the corresponding motor, the ARM chip and the signal conditioning circuit are in communication with each other, the input end of the signal conditioning circuit is connected to the AD sampling expansion chip and the bus voltage phase current detection circuit, the input end of the AD sampling expansion chip is connected to the position detection circuit, the input end of the position detection circuit is connected to the first position sensor and the corresponding second position sensor or third position sensor, the input end of the bus voltage phase current detection circuit is connected to the corresponding turning drive module for acquiring voltage signals, current signals and temperature signals during the operation of the motor, and the output end of the signal conditioning circuit is connected to the commutation logic circuit for providing commutation control signals.

[0014] The ARM chip is also connected to the FLASH chip and a communication module, the FLASH chip is used for storing preset parameters and state information in the system working process, and the output end of the power module is connected to the power input ends of each chip and circuit.

[0015] The ARM chips of the two turning control modules are connected to each other through cross-processor.

[0016] Further, the two turning drive modules each comprise an IPM module, a temperature sensor, a voltage sampling chip and two phase current sampling chips.

[0017] The DC bus end of the IPM module is connected with the power module, the input end of the IPM module is connected with the isolation circuit, the U, V and W three-phase AC output ends of the IPM module are connected with the three stator winding terminals of the corresponding motor respectively, and a phase current sampling chip is connected in series between the U and V two-phase AC output ends of the IPM module and the corresponding motor respectively; the DC bus negative end of the IPM module is connected with the voltage sampling chip; and the temperature sensor is installed on the corresponding motor.

[0018] The output ends of the temperature sensor, the voltage sampling chip and the two phase current sampling chips are connected with the input ends of the bus voltage and phase current detection circuit respectively.

[0019] Further, NMOS field effect transistors are connected in series between the negative end of the power module and the corresponding ARM chip and between the negative end of the power module and the corresponding IPM module respectively for reverse connection protection of the power supply.

[0020] Further, the communication module comprises a CAN port and an RS485 communication serial port, and a parallel data receiver mechanism is established to form CAN and RS485 dual-mode redundant communication.

[0021] A front wheel steering rudder machine redundant control method for a UAV, based on the front wheel steering rudder machine redundant control system according to any one of the above; characterized in that, comprising the following steps:

[0022] S1, after the system is powered on, the two turning control modules exchange decision information and position feedback signals for closed loop in real time through cross-processor, and the two turning control modules respectively construct driving algorithms according to the collected position feedback signals;

[0023] S2, the two turning control modules receive external control instructions simultaneously through the communication module, solve the external control instruction information, and the two turning control modules transmit the solved external control instruction information to each other through cross-processor backup;

[0024] S3, the two main turning control modules mobilize the driving algorithms according to the external control instructions, generate motor driving PWM signals and transmit them to the corresponding turning driving modules, and the two turning control modules control the motors connected thereto through the corresponding turning driving modules according to the motor driving PWM signals, jointly drive the gear set to work, so that the gear mechanism and the front landing gear of the UAV cooperate to execute the corresponding steering action of the external control instruction;

[0025] S4, the two turning control modules respectively collect voltage signals, current signals and temperature signals when the corresponding turning driving modules control the motor to operate, compare the three with the preset signal range to determine whether an abnormality occurs and output a feedback signal, the two turning control modules share the feedback signal through cross-processor; if the determination result is no, the current control continues until the steering control of the unmanned aerial vehicle is completed; if the determination result is yes, a fault signal is output by the turning control module where the abnormality occurs and sent to the corresponding turning driving module;

[0026] S5, the turning driving module receiving the fault signal controls the corresponding motor to stop and no longer output power, the normal motor driving PWM signal is generated by the turning control module where no abnormality occurs and transmitted to the corresponding turning driving module, the motor connected with the turning driving module is controlled to operate normally, the gear set is driven by the single motor to work, the gear mechanism cooperates with the unmanned aerial vehicle front landing gear to execute the external control instruction to perform the corresponding steering action, until the steering control of the unmanned aerial vehicle is completed.

[0027] Further, the specific method for the two turning control modules to exchange decision information and position feedback signals for closed loop in real time through cross-processor in step S1 is:

[0028] The position feedback signals can be shared in real time by the ARM chips of the two turning control modules through cross-processor, the ARM chip of the main turning control module establishes a confidence evaluation model of the three position sensor feedback signals based on a priority-based fault diagnosis algorithm, adopts a sliding window dynamic analysis to evaluate the reliability of the position sensor data, when the first position sensor is detected to exceed the preset deviation threshold, the system adaptively switches to the second position sensor of the sub-priority according to the real-time confidence weight, when the second position sensor is detected to still exceed the preset deviation threshold, the system adaptively switches to the third position sensor of the lowest priority according to the real-time confidence weight, forming a redundant control strategy with fault tolerance characteristics;

[0029] Meanwhile, the decision information and position feedback signals for closed loop are exchanged in real time between the ARM chips of the two turning control modules, the PID control loop is respectively constructed based on the unified position feedback signals, and the position feedback information for closed loop control between the ARM chips of the two turning control modules is ensured to be consistent.

[0030] Further, the specific way for the two turning control modules to simultaneously receive the external control instruction in step S2 is:

[0031] The ARM chips of the two turning control modules synchronously receive the external control instruction of the external flight control machine through the double communication interface composed of CAN port and RS485 communication serial port, and follow a dynamic adjustment strategy based on priority:

[0032] The two turning control modules prefer to execute external control instructions received through the CAN port. When it is detected that no legal instructions conforming to the protocol specification are received through the CAN port for 250 ms, the ARM chip of the corresponding turning control module will automatically switch to execute external control instructions received through the RS485 communication serial port.

[0033] Meanwhile, the ARM chip of the corresponding turning control module keeps monitoring the CAN port in real time in this state. If more than 25 frames of valid external control instructions are captured, the communication mode adaptive switching mechanism is triggered to restore the CAN port as the main communication channel for realizing autonomous diagnosis and seamless switching of communication link failure.

[0034] Further, the step S3 is specifically:

[0035] The ARM chips of the two turning control modules generate motor drive PWM signals according to external control instructions and deliver the signals to the corresponding turning drive modules. When the external communication of the ARM chip of one of the turning control modules is interrupted, the ARM chip of the turning control module continues to generate motor drive PWM signals and deliver the signals to the corresponding turning drive module according to the external control instruction information delivered by the ARM chip of the other turning control module.

[0036] The buffer circuits corresponding to the two turning control modules convert the motor drive PWM signals from 3.3V to 5V. After the converted motor drive PWM signals pass through the isolation circuit, the signals are input to the corresponding IPM modules to control the corresponding motors to operate. The two motors jointly drive the gear set to work, so that the gear mechanism cooperates with the unmanned aerial vehicle front landing gear to execute corresponding turning actions according to external control instructions.

[0037] Further, the step S4 is specifically:

[0038] The two turning control modules respectively collect voltage signals, current signals and temperature signals of the corresponding motors in operation by the corresponding voltage sampling chips, two phase current sampling chips and temperature sensors, and deliver the collected three kinds of signals to the signal conditioning circuit through the bus voltage and phase current detection circuit. The signal conditioning circuit compares the collected three kinds of signals with the preset signal range to determine whether an abnormality occurs in the two turning control modules and outputs a feedback signal to the corresponding ARM chip. The two ARM chips realize feedback signal sharing through cross-processor. If the judgment results of the two signal conditioning circuits are both no, the turning control of the unmanned aerial vehicle is completed. If the judgment result of any one is yes, the signal conditioning circuit with the yes result outputs a fault signal and sends the signal to the ARM chip of the abnormal turning control module, and then the ARM chip of the abnormal turning control module sends the fault signal to the corresponding turning drive module.

[0039] Compared with the prior art, the present application has the following beneficial effects:

[0040] (1) The unmanned aerial vehicle front wheel steering rudder machine redundancy control system of the present application establishes a cooperative control architecture based on cross-processor real-time communication. By constructing a multi-source data fusion mechanism, real-time synchronization and sharing of position sensor information between dual ARM chips are realized, avoiding interference caused by inconsistent position feedback and mechanical differences when each ARM chip drives the motor to drive the transmission module. By exchanging position feedback information between dual ARM chips in real time, consistent position feedback is ensured, and mechanical interference after gear meshing in the dual transmission module is reduced.

[0041] (2) The unmanned aerial vehicle front wheel steering rudder machine redundancy control system of the present application adopts a dual-ARM architecture cooperative control strategy to realize redundancy fault-tolerant control of a mechanically coupled single-axis drive system. Two ARM chips independently drive two motors, and a mechanically coupled output structure is formed through precise gear meshing. Each ARM chip is provided with a CAN port and an RS485 communication serial port and establishes a parallel data receiving mechanism. If any link in the control circuit or communication link fails, the system can realize autonomous diagnosis and seamless switching, and can ensure normal use of the unmanned aerial vehicle front wheel steering rudder machine steering function while reporting fault information. In the presence of electromagnetic interference, high vibration or extreme temperature and humidity environmental conditions, the redundancy control strategy of the three position sensors can ensure normal feedback of the steering position information and normal function of the closed-loop control, ensuring that the system has no single-point failure risk.

[0042] (3) The unmanned aerial vehicle front wheel steering rudder machine redundancy control system of the present application is based on an ARM chip front wheel steering rudder machine controller, which adopts a distributed control scheme. It not only adapts to different configurations of unmanned aerial vehicle landing gear, but also has low hardware modification cost. Compared with traditional mechanical redundancy, it meets the demand of unmanned aerial vehicle lightweight, and solves the problem of system integration and compatibility limitation of existing front wheel steering rudder machines.

[0043] (4) The unmanned aerial vehicle front wheel steering rudder machine redundancy control method of the present application synchronously receives external control instructions through dual communication interfaces, and follows a dynamic adjustment strategy based on priority to preferentially execute effective instruction data of the CAN bus and maintain real-time monitoring of the CAN bus state. According to the monitoring situation, the RS485 communication mode is adaptively switched to realize autonomous diagnosis and seamless switching of the communication link. Through the three-level redundancy control strategy of the three position sensors, the dynamic synchronization performance and fault tolerance of the system are enhanced. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1 Figure 1 is a structural schematic diagram of an unmanned aerial vehicle front wheel steering rudder machine redundancy control system according to an embodiment of the present application;

[0045] Figure 2A structural block diagram of a turning control module in a front wheel steering rudder redundant control system for a UAV according to an embodiment of the present application;

[0046] Figure 3 A structural block diagram of a turning driving module in a front wheel steering rudder redundant control system for a UAV according to an embodiment of the present application;

[0047] Figure 4 A three-position sensor redundant control strategy block diagram in a front wheel steering rudder redundant control method for a UAV according to an embodiment of the present application;

[0048] Figure 5 A three-position sensor redundant mechanism block diagram in a front wheel steering rudder redundant control method for a UAV according to an embodiment of the present application;

[0049] Figure 6 A CAN and RS485 dual-mode redundant communication strategy block diagram in a front wheel steering rudder redundant control method for a UAV according to an embodiment of the present application;

[0050] Figure 7 A connection relationship diagram of a power module and an IPM module in a front wheel steering rudder redundant control system for a UAV according to an embodiment of the present application. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0052] As shown in Figure 1 the present embodiment provides a front wheel steering rudder redundant control system for a UAV, which adopts a dual-ARM architecture cooperative control strategy and includes two turning control modules, two turning driving modules, three position sensors, two communication modules, two power modules and a transmission module. The two turning control modules are connected to each other through cross-processor. One of the turning control modules is connected to the corresponding turning driving module, motor and communication module, and the other turning control module is also connected to the corresponding turning driving module, motor and communication module. The transmission module includes a gear set and a gear mechanism. The gear set includes a gear and two input gear shafts which are in meshing transmission with the gear. The output ends of the two motors are connected to the input gear shafts, and the gear is in transmission connection with the gear mechanism for realizing steering action in cooperation with the front landing gear of the UAV. The position sensors are installed on the gear and the two input gear shafts respectively. One power module is connected to one turning control module and one turning driving module, and the other power module is connected to the other turning control module and the other turning driving module.

[0053] As shown in Figure 2As shown, the two turning control modules each contain an ARM chip, an AD sampling expansion chip, a FLASH chip, a Hall signal detection circuit, a commutation logic circuit, a buffer circuit, a position detection circuit, a bus voltage phase current detection circuit and a signal conditioning circuit; the ARM chip is connected to the FLASH chip, and in turn is connected to the buffer circuit, the commutation logic circuit and the isolation circuit, the feedback input end of the commutation logic circuit is connected to the Hall signal detection circuit, the commutation logic circuit mainly includes AND gate, NOT gate, OR gate and other gate circuits, decodes and processes the received motor Hall signals, and converts the PWM signals output by the single ARM chip into 6 groups of driving signals required by the motor drive, effectively reduces the commutation time of the ARM chip in the entire control cycle, improves the utilization rate of the control unit, and improves the response speed of the entire system; the ARM chip and the signal conditioning circuit are in communication with each other, the input end of the signal conditioning circuit is connected to the AD sampling expansion chip and the bus phase current detection circuit, and the signal conditioning circuit and the buffer circuit are used for amplifying and filtering the feedback signals of voltage, current, position and the like, filtering out the noise on the signals, limiting these signals within the effective range and transmitting them to the ARM chip for calculation and processing; the input end of the AD sampling expansion chip is connected to the position detection circuit, and the input end of the position detection circuit is connected to three position sensors, the position sensor mounted on the gear is set as a first position sensor, the position sensors mounted on the two input gear shafts are set as a second position sensor and a third position sensor, and the first position sensor adopts a double-channel acquisition architecture to access the AD sampling expansion chip through the position detection circuit; the second position sensor and the third position sensor are connected to the corresponding AD sampling expansion chip through the position detection circuit, ensuring that each ARM chip has double-channel position information cross verification capability and realizing seamless switching of the position sensor; the output end of the signal conditioning circuit is connected to the commutation logic circuit; the two ARM chips are connected to each other through cross-processor.

[0054] The two turning control modules each include an IPM module, a temperature sensor, a voltage sampling chip and two phase current sampling chips; as Figure 3As shown, the DC bus end of the IPM module is connected to the power module, and the input end is connected to the isolation circuit; the U, V, and W three-phase AC output ends of the IPM module are respectively connected to the three stator winding terminals of the corresponding motor, and a phase current sampling chip is respectively connected in series between the U and V two-phase AC output ends of the IPM module and the motor; the DC bus negative end of the IPM module is connected to the voltage sampling chip; the temperature sensor is installed on the corresponding motor; the output ends of the temperature sensor, the voltage sampling chip, and the two phase current sampling chips are connected to the input end of the bus voltage and current detection circuit, the bus voltage and current detection circuit is used to collect voltage, current, and temperature signals and transmit them to the corresponding signal conditioning circuit, the signal conditioning circuit processes the received voltage, current, and temperature signals to obtain voltage fault signals, current fault signals, and temperature fault signals and transmits them to the corresponding ARM chip.

[0055] The power module includes a power conversion circuit and a power anti-reverse connection circuit, the power conversion circuit is connected to the two ARM chips and the two IPM modules, as shown Figure 7 As shown, the power anti-reverse connection circuit is composed of a NMOS field effect transistor connected in series between the negative end of the power conversion circuit and the IPM module, when the power polarity is reversed, due to the internal body diode of the NMOS field effect transistor, the reverse current is prevented from flowing in, achieving the purpose of power anti-reverse connection.

[0056] Both communication modules include CAN ports and RS485 communication serial ports, and establish parallel data receivers to form CAN and RS485 dual-mode redundant communication, realize autonomous diagnosis and seamless switching of communication link faults, and ensure the communication reliability of the system in complex electromagnetic environments.

[0057] A front wheel steering rudder redundancy control method for a UAV, applied to the front wheel steering rudder redundancy control system for a UAV as described above; comprising the following steps:

[0058] S1, set one of the two turning control modules as the main turning control module, and the other as the auxiliary turning control module; after the system is powered on, the ARM chips of the two turning control modules establish a confidence evaluation model of the three position sensor feedback signals based on a priority fault diagnosis algorithm, and perform reliability evaluation on the position sensor data by using a sliding window dynamic analysis, when it is detected that the first position sensor exceeds a preset deviation threshold, the system adaptively switches to the second position sensor with a sub-priority according to the real-time confidence weight, when it is detected that the second position sensor still exceeds the preset deviation threshold, the system adaptively switches to the third position sensor with the lowest priority according to the real-time confidence weight, forming a redundancy control strategy with fault tolerance characteristics; and the ARM chips of the two turning control modules can share the position feedback signals in real time through cross-processor real-time synchronization, and the two turning control modules construct a driving algorithm according to the collected position feedback signals.

[0059] The three-position sensor redundancy control strategy is as shown in Figure 4 and Figure 5 The specific process is as follows, taking the main turning control module as an example:

[0060] S1.1, the main turning control module receives three position feedback signals monitored by three position sensors through the AD sampling expansion chip connected thereto, and then transmits the three position feedback signals processed by a signal conditioning circuit to the ARM chip of the main turning control module;

[0061] S1.2, the ARM chip judges whether the first position sensor is normal; if the result is yes, then regardless of the subsequent judgment results of whether the second position sensor and the third position sensor are normal or not, the ARM chip of the main turning control module only transmits the processed first position feedback signal to the ARM chip of the auxiliary turning control module through cross-processor for PID control; if the result is no, then it is judged whether the second position sensor is normal;

[0062] S1.3, if the result of judging whether the second position sensor is normal is yes, then regardless of the subsequent judgment results of whether the third position sensor is normal or not, the ARM chip of the main turning control module only transmits the processed second position feedback signal to the ARM chip of the auxiliary turning control module through cross-processor for PID control; if the result is no, then it is judged whether the third position sensor is normal;

[0063] S1.4, if the result of judging whether the third position sensor is normal is yes, then the ARM chip of the main turning control module transmits the processed third position feedback signal to the ARM chip of the auxiliary turning control module through cross-processor for PID control; if the result is no, then the control system is shut down.

[0064] The two ARM chips construct PID control loops based on unified position feedback signals, ensuring that the position feedback signals used by the dual-ARM chips for closed-loop control are consistent. This design effectively solves the hysteresis problem of the traditional master-slave architecture, improving the motion synchronization accuracy and anti-interference ability under the gear engagement condition. Experimental verification shows that this architecture can significantly reduce mechanical interference after the gear engagement of the dual-drive module of the front wheel steering rudder of the unmanned aerial vehicle, while enhancing the dynamic synchronization performance and fault tolerance of the system.

[0065] At the same time, in order to optimize the position sensor signal quality, the system uses a filtering algorithm combined with hardware filtering, which effectively reduces the collection noise while maintaining a small phase lag characteristic.

[0066] S2. The two turning control modules simultaneously receive external control commands through the communication module, calculate the external control command information, and the two turning control modules back up the calculated external control command information by passing it between processors.

[0067] As attached Figure 6 As shown, the ARM chips of both turning control modules synchronously receive external control commands from the external flight controller through a dual communication interface consisting of a CAN port and an RS485 serial communication port, and follow a priority-based dynamic adjustment strategy:

[0068] The two turning control modules prioritize executing external control commands received through the CAN port. When the CAN port fails to receive a valid command conforming to the protocol specification for 250ms, the ARM chip of the corresponding turning control module will automatically switch to execute external control commands received through the RS485 communication serial port.

[0069] Meanwhile, in this state, the ARM chip of the corresponding turning control module maintains real-time monitoring of the CAN port communication. If more than 25 valid external control commands that have passed verification are captured continuously, the communication mode adaptive switching mechanism is triggered to restore the CAN port as the main communication channel, which is used to realize the autonomous diagnosis and seamless switching of communication link failures.

[0070] S3. The two turning control modules activate the drive algorithm according to the external control command, generate the motor drive PWM signal and pass it to the corresponding turning drive module. However, when the external communication of the ARM chip of one of the turning control modules is interrupted, the ARM chip of that turning control module calls the external control command information passed by the ARM chip of the other turning control module to continue to generate the motor drive PWM signal and pass it to the corresponding turning drive module.

[0071] The buffer circuits corresponding to the two turning control modules convert the motor drive PWM signal from 3.3V to 5V. The converted motor drive PWM signal is then input to the corresponding IPM module through the isolation circuit to control the operation of the corresponding motor. The two motors work together to drive the gear set, so that the gear mechanism cooperates with the UAV's front landing gear to execute external control commands and perform corresponding turning actions.

[0072] S4, the two turning control modules are respectively controlled by the corresponding voltage sampling chip, two phase current sampling chips and temperature sensors to collect the voltage signal, current signal and temperature signal during the corresponding motor operation, and the three signals collected are transmitted to the signal conditioning circuit through the bus voltage phase current detection circuit, the signal conditioning circuit compares the three signals collected with the preset signal range to determine whether an abnormality occurs in the two turning control modules and outputs a feedback signal to the corresponding ARM chip, the two ARM chips share the feedback signal through cross-processor; if the judgment results of the two signal conditioning circuits are both no, the turning control of the unmanned aerial vehicle is completed; if the judgment result of any one is yes, the signal conditioning circuit with the yes result outputs a fault signal and sends it to the ARM chip of the turning control module with the abnormality, and then the ARM chip of the turning control module with the abnormality sends the fault signal to the corresponding turning drive module.

[0073] S5, the turning drive module receiving the fault signal controls the corresponding motor to stop and no longer outputs power, the turning control module without abnormality normally generates the motor drive PWM signal, which is transmitted to the corresponding IPM module, and the motor connected with the IPM module continues to operate normally, the single motor drives the gear set to work, so that the gear mechanism cooperates with the unmanned aerial vehicle front landing gear to execute the external control instruction to perform the corresponding turning action, and the turning control of the unmanned aerial vehicle is completed.

[0074] The above is only an embodiment of the present application and is not used to limit the present application, for ordinary skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the technical solution of the present application should be included in the protection scope of the present application. In addition, it should be noted that the drawings are only examples and are not drawn according to the condition of the same proportion, and should not be used as a limitation on the protection scope actually required by the present application.

Claims

1. A redundancy control system for a front wheel steering rudder of a drone, characterized in that, The system comprises: two control units with the same structure, a transmission module and three position sensors; the control unit comprises a power module and a communication module, a turning control module, a turning driving module and a motor connected in sequence; the turning control modules of the two control units are connected through cross-processor communication for real-time sharing of information and cooperative control of the turning driving module; the turning control module receives external control instructions through the communication module and generates a turning control signal; the turning driving module generates a driving voltage according to the received turning control signal to drive the corresponding motor to work; the power module supplies power to the corresponding turning control module and turning driving module; the transmission module comprises a gear set and a gear mechanism, the gear set comprises a gear and two input gear shafts in meshing transmission with the gear, the output ends of the two motors are connected with the input gear shafts respectively for jointly driving the gear to work; the gear is in transmission connection with the gear mechanism for realizing steering action in cooperation with the front landing gear of the unmanned aerial vehicle; one of the three position sensors is a first position sensor, the first position sensor is installed on the gear of the gear set, and the output end thereof adopts a double-channel acquisition architecture to access the two turning control modules simultaneously; the other two position sensors are a second position sensor and a third position sensor respectively, the second position sensor and the third position sensor are installed on the two input gear shafts of the gear set respectively, and the output ends thereof access the two turning control modules respectively; the three position sensors are used for collecting position feedback signals of the gear and the input gear shafts.

2. The front wheel steering rudder machine redundancy control system for unmanned aerial vehicles according to claim 1, characterized in that: the turning control module comprises an ARM chip, an AD sampling expansion chip, a FLASH chip, a Hall signal detection circuit, a commutation logic circuit, an isolation circuit, a buffer circuit, a position detection circuit, a bus voltage phase current detection circuit and a signal conditioning circuit; the control signal output end of the ARM chip is connected with the buffer circuit, the commutation logic circuit and the isolation circuit in sequence, the output end of the isolation circuit is connected with the input end of the turning driving module; the feedback input end of the commutation logic circuit is connected with the Hall signal detection circuit, the input end of the Hall signal detection circuit is connected with the rotor end of the corresponding motor; the ARM chip and the signal conditioning circuit are in communication with each other, the input end of the signal conditioning circuit is connected with the AD sampling expansion chip and the bus voltage phase current detection circuit; the input end of the AD sampling expansion chip is connected with the position detection circuit, and the input end of the position detection circuit is connected with the first position sensor and the corresponding second position sensor or third position sensor; the input end of the bus voltage phase current detection circuit is connected with the corresponding turning driving module for collecting voltage signals, current signals and temperature signals during the operation of the motor, and the output end of the signal conditioning circuit is connected with the commutation logic circuit for providing commutation control signals; The ARM chip is also connected with the FLASH chip and the communication module, the FLASH chip is used for storing preset parameters and state information in the system working process, and the output end of the power module is connected with the power input ends of the chips and the circuit. The ARM chips of the two turning control modules are connected with each other through cross-processors.

3. The front wheel steering redundancy control system for the unmanned aerial vehicle according to claim 2, characterized in that: The two turning driving modules each comprise an IPM module, a temperature sensor, a voltage sampling chip and two phase current sampling chips. The DC bus end of the IPM module is connected with the power module, the input end of the IPM module is connected with the isolation circuit, the U, V and W three-phase alternating current output ends of the IPM module are connected with the three stator winding terminals of the corresponding motor respectively, and one phase current sampling chip is connected in series between the U and V two-phase alternating current output ends of the IPM module and the corresponding motor respectively; the DC bus negative end of the IPM module is connected with the voltage sampling chip; and the temperature sensor is installed on the corresponding motor. The output ends of the temperature sensor, the voltage sampling chip and the two phase current sampling chips are connected with the input ends of the bus voltage and phase current detection circuit respectively.

4. The front wheel steering redundancy control system for the unmanned aerial vehicle according to claim 3, characterized in that: NMOS field effect transistors are connected in series between the negative end of the power module and the corresponding ARM chip and between the negative end of the power module and the corresponding IPM module respectively, for reverse connection protection of the power supply.

5. The front wheel steering redundancy control system for the unmanned aerial vehicle according to claim 4, characterized in that: The communication module comprises a CAN port and an RS485 communication serial port, and a parallel data receiver mechanism is established to form CAN and RS485 dual-mode redundant communication.

6. A redundancy control method for a front wheel steering rudder of a UAV, based on the redundancy control system for the front wheel steering rudder of the UAV according to any one of claims 1-5; characterized in that, The method comprises the following steps: S1, after the system is powered on, the two turning control modules exchange decision information and position feedback signals for closed loop in real time through cross-processors, and the two turning control modules respectively construct driving algorithms according to the collected position feedback signals; S2, the two turning control modules receive external control instructions simultaneously through the communication module, solve the external control instruction information, and the two turning control modules transmit the solved external control instruction information to each other through cross-processors for backup; S3, the two turning control modules mobilize the driving algorithms according to the external control instructions, generate motor driving PWM signals and transmit the motor driving PWM signals to the corresponding turning driving modules respectively, and the two turning control modules control the motors connected with the corresponding turning driving modules through the corresponding turning driving modules according to the motor driving PWM signals, drive the gear set to work together, so that the gear mechanism and the unmanned aerial vehicle front landing gear cooperate to execute the corresponding steering action of the external control instructions; S4, the two turning control modules respectively collect voltage signals, current signals and temperature signals when the corresponding turning driving modules control the motor to operate, compare the three with the preset signal range to determine whether an abnormality occurs and output a feedback signal, the two turning control modules share the feedback signal through cross-processor; if the determination result is no, the current control continues until the steering control of the unmanned aerial vehicle is completed; if the determination result is yes, the turning control module where the abnormality occurs outputs a fault signal and sends it to the corresponding turning driving module; S5, the turning driving module receiving the fault signal controls the corresponding motor to stop and no longer output power, the normal motor driving PWM signal is generated by the turning control module where no abnormality occurs and is transmitted to the corresponding turning driving module, the motor connected with the turning driving module is controlled to operate normally, the gear set is driven by the single motor to work, the gear mechanism cooperates with the unmanned aerial vehicle front landing gear to execute the external control instruction to perform the corresponding steering action, and the steering control of the unmanned aerial vehicle is completed.

7. The front wheel steering rudder machine redundancy control method for a UAV according to claim 6, characterized in that, The specific method for the two turning control modules to exchange decision information and position feedback signals for closed loop in real time in step S1 is: The two turning control modules can share the position feedback signals in real time through cross-processor between the ARM chips of the two turning control modules, the ARM chips of the two turning control modules establish a confidence evaluation model of the three position sensor feedback signals based on a priority-based fault diagnosis algorithm, the reliability of the position sensor data is evaluated by dynamic analysis of a sliding window, when it is detected that the first position sensor exceeds the preset deviation threshold, the system adaptively switches to the second position sensor of the sub-priority according to the real-time confidence weight, when it is detected that the second position sensor still exceeds the preset deviation threshold, the system adaptively switches to the third position sensor of the lowest priority according to the real-time confidence weight, forming a redundant control strategy with fault tolerance characteristics; Meanwhile, the two turning control modules exchange decision information and position feedback signals for closed loop in real time between the ARM chips of the two turning control modules, and respectively construct PID control loops based on the unified position feedback signals, to ensure that the position feedback information for closed loop control between the ARM chips of the two turning control modules is consistent.

8. The front wheel steering rudder machine redundancy control method for a UAV according to claim 7, characterized in that, The specific way for the two turning control modules to simultaneously receive external control instructions in step S2 is: The ARM chips of the two turning control modules synchronously receive external control instructions of the external flight control machine through a double communication interface composed of a CAN port and an RS485 communication serial port, and follow a dynamic adjustment strategy based on priority: The two turning control modules preferentially execute the external control instructions received by the CAN port, and when it is detected that the CAN port does not receive a legal instruction conforming to the protocol specification for 250 ms, the ARM chip of the corresponding turning control module will automatically switch to execute the external control instruction received by the RS485 communication serial port; Meanwhile, the ARM chip corresponding to the turning control module in this state keeps real-time monitoring of CAN port communication, and if more than 25 frames of valid external control instructions are continuously captured, the communication mode adaptive switching mechanism is triggered to restore the CAN port as the main communication channel for realizing autonomous diagnosis and seamless switching of communication link failure.

9. The front wheel steering rudder machine redundancy control method for a UAV according to claim 8, wherein, Step S3 is specifically: The ARM chips of the two turning control modules generate motor drive PWM signals according to the external control instructions and deliver them to the corresponding turning drive modules; but when the external communication of the ARM chip of one of the turning control modules is interrupted, the ARM chip of the turning control module calls the external control instruction information delivered by the ARM chip of the other turning control module, and continues to generate motor drive PWM signals and deliver them to the corresponding turning drive module; The buffer circuits corresponding to the two turning control modules convert the motor drive PWM signals from 3.3V to 5V, and the converted motor drive PWM signals are input to the corresponding IPM modules after passing through the isolation circuit to control the corresponding motor to operate, and the two motors jointly drive the gear set to work, so that the gear mechanism cooperates with the unmanned aerial vehicle front landing gear to execute the corresponding turning action of the external control instruction.

10. The front wheel steering rudder machine redundancy control method for a UAV according to claim 9, wherein, Step S4 is specifically: The two turning control modules respectively collect the voltage signal, current signal and temperature signal of the corresponding motor during operation by the corresponding voltage sampling chip, two phase current sampling chips and temperature sensor, and deliver the collected three signals to the signal conditioning circuit through the bus voltage and phase current detection circuit, and the signal conditioning circuit compares the collected three signals with the preset signal range to determine whether an abnormality occurs in the two turning control modules and outputs a feedback signal to the corresponding ARM chip. The two ARM chips realize feedback signal sharing through cross-processor; if the judgment results of the two signal conditioning circuits are both no, the turning control of the unmanned aerial vehicle is completed; if the judgment result of any one is yes, the signal conditioning circuit with the yes result outputs a fault signal and sends it to the ARM chip of the abnormal turning control module, and then the ARM chip of the abnormal turning control module sends the fault signal to the corresponding turning drive module.

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