A piston engine simulation system for unmanned helicopters

Abstract

The present invention provides a piston engine simulation system for an unmanned helicopter, comprising a piston engine simulation control terminal, an acquisition sensor simulation terminal, a fault injection terminal, a data acquisition terminal, a motor, a torque loader and a throttle servo. The present invention has the effect that, under the condition of reducing the test cost and the test risk, the real-time simulation and simulation test and test of the power system can be met; and effective experimental means and data support are provided for the control law design and improvement of the flight control system.

Description

Technical Field

[0001] The invention relates to a piston engine simulation system for an unmanned helicopter. Background Art

[0002] At present, the flight control simulation system of unmanned helicopters can usually only simulate or simulate the flight control rate, flight control system and sensor system, and cannot simulate and test the whole system of the power system. The use of real machine testing is limited by conditions such as site, cost, and fuel safety. When the fuselage, rotor, etc. change, the control law of the whole machine needs to be re-balanced and calibrated, which has the disadvantages of high cost and long cycle. Summary of the invention

[0003] Purpose of the invention: To solve the technical problems existing in the background technology, the present invention proposes a piston engine simulation system for an unmanned helicopter. The system controls the speed of the motor through the engine mathematical model and the load requirements set for the motor by the flight control system, and can simulate certain fault injections. The system has a simple structure and is easy to use and maintain.

[0004] The present invention comprises a piston engine simulation control terminal (1), a sensor simulation terminal (2), a fault injection terminal (3), a data acquisition terminal (4), a motor (5), a torque load device (6) and a throttle steering gear (7);

[0005] The piston engine simulation control terminal (1) controls the motor (5), the torque load device (6) and the throttle steering gear (7) according to the flight control system instruction, through the engine temperature and pressure data of the sensor simulation terminal (2) and the engine fault state simulation data set by the fault injection terminal (3), so as to simulate the real operation state of the engine, and collects the information of the motor and the throttle steering gear through the data acquisition terminal (4) and transmits it back to the flight control system.

[0006] The motor control algorithm and control software matching the voltage-speed curve, speed-load curve and mechanical time constant of the motor (5) are designed, the rotation of the motor (5) is controlled by a driving module, and the control parameters of the torque load device (6) are corrected according to the real-time feedback data of the speed of the motor (5), so as to simulate the operation of the engine and the load and throttle relationship response under the condition of constant speed, so as to simulate, emulate and correct the accuracy of the engine control by the flight control software of the unmanned helicopter, and reduce the risk during the flight process.

[0007] The piston engine simulation control terminal (1) includes an embedded motor control unit and an engine throttle load data model, and according to the embedded engine throttle load data model, according to the mechanical time constant and speed load curve of the rear-end motor (5), the voltage of the motor and the control voltage of the torque load device are controlled by designing a software algorithm and a control method, thereby solving the problem that the test of the response between the throttle, speed and torque of the piston engine can only be carried out on an engine test bench, which requires high site and personnel.

[0008] The sensor simulation terminal (2) simulates the engine intake pressure and cylinder head temperature information under different speed conditions according to the engine model;

[0009] The fault injection terminal (3) simulates fault injection into the signals of various sensors of the engine by pressing keys, so as to test the reaction state of the engine under various faults;

[0010] The data acquisition terminal (4) acquires the speed signal of the motor (5) and the opening signal of the throttle steering gear (7), and feeds back the acquired data to the flight control system, thereby forming a closed-loop control of the engine by the flight control system, so as to evaluate or correct the effect of the flight control system under different circumstances.

[0011] The control voltage U of the motor (5) t It is usually written as follows:

[0012]

[0013] Among them, k 0 is the proportional constant, N 0 is the target speed, N t Current speed, U N is the nominal voltage, I 0 is the no-load current, n 0 is the no-load speed, and R is the terminal resistance.

[0014] The control voltage U of the torque load device (6) t ′ for:

[0015]

[0016] Among them, K 0 is the control constant of the torque load device (6), M 0 is the rated torque, the updated speed N t ′ =k 1 N t f(t), k 1 is the transmission ratio coefficient, and f(t) is the piston engine data model table.

[0017] The piston engine simulation control terminal (1) adopts a single-chip microcomputer embedded piston engine control model, and according to the instructions of the flight control system, realizes that when the unmanned helicopter is in different working conditions, such as clutch state, hovering state, level flight state, climbing or diving state, according to the different loads set, the simulated control voltage of the motor (5) under different working conditions is calculated and corrected, and the response of the engine under actual working conditions is simulated to evaluate the planning and effectiveness of the flight control software.

[0018] The beneficial effects of the present invention are: (1) it can meet the actual simulation and simulation test and experiment of the power system under the condition of reducing the test cost and test risk; (2) it provides effective experimental means and data support for the design and improvement of the control law of the flight control system; (3) the injection and simulation of real-time faults of various engine sensors also provide real-life testing and verification for the flight control safety protection strategy, thereby increasing the success rate of subsequent whole-machine tests and reducing test risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, and the above and / or other advantages of the present invention will become more clear.

[0020] Figure 1 It is a structural diagram of the present invention. DETAILED DESCRIPTION

[0021] like Figure 1 As shown, the present invention provides a piston engine simulation system for an unmanned helicopter, including a piston engine simulation control terminal 1, a sensor simulation terminal 2, a fault injection terminal 3, a data acquisition terminal 4, a motor 5, a torque loader 6 and a throttle servo 7;

[0022] The piston engine simulation control terminal 1 uses an STM32F407 series single-chip microcomputer with an embedded piston engine data model. According to the instructions of the flight control system, the designed software algorithm and control strategy use a brushless motor to control the speed of the motor 5 under different working conditions to simulate the engine;

[0023] The response between the throttle, speed and torque of a piston engine is usually in the second level, and the response between the motor voltage, speed and torque is usually in the millisecond level. During the control process, it is necessary to apply a certain damping to the different working conditions of the motor to achieve the purpose of simulating the operation of the engine in a realistic manner.

[0024] Usually, to achieve the target speed, the control voltage of the motor is written as follows:

[0025]

[0026] Among them, k0 Proportional constant, N 0 is the target speed, N t Current speed, U N Nominal voltage, I 0 is the no-load current, and R is the terminal resistance.

[0027] Since the mechanical time constant of the motor is an inherent characteristic of the motor body and is related to the rotational inertia and torque constant of the electronic rotor, in order to achieve the purpose of simulating the start control response curve, the present invention introduces a torque loader as one of the control targets in the motor control method.

[0028] The torque load is controlled in the following way:

[0029]

[0030] Among them, K 0 Control constant for moment load, M 0 is the rated torque, the updated speed N t ′ =k 1 N t f(t), f(t) is the piston engine data model table.

[0031] Therefore, the control equation of the motor in the system can be modified as follows:

[0032] U=U t +KU t ′

[0033] in: K is the torque coefficient of the motor and the torque load,

[0034] The sensor simulation terminal 2 simulates different engine intake pressure, cylinder head temperature and other information according to the engine model and speed;

[0035] The fault injection terminal 3 can perform fault simulation injection on the engine sensor information and control signal by pressing a button;

[0036] The data acquisition terminal 4 collects the speed signal of the motor 5 and the opening signal of the KST A20 throttle servo 7, and can perform load simulation injection on the motor 5 according to the flight control system command to complete the closed-loop control of the flight control system on the engine.

[0037] The piston engine simulation control terminal 1 is implemented by a single chip microcomputer and a drive circuit. Through the existing unmanned helicopter piston engine control system, speed, throttle, load curve, combined with the data model of the engine, the mathematical model of the engine control system is fitted, and the corresponding torque load is applied to the motor 5 to achieve the load fluctuation simulation of the power system. A DC brushless motor 5 is used to simulate the engine. The single chip microcomputer performs corresponding starting, acceleration, deceleration and parking control on the motor 5 through the drive circuit according to the flight control system instructions, the engine starting process and the speed curve.

[0038] The piston engine simulation control terminal 1 adopts two mathematical models of piston engines for unmanned helicopters embedded in the single-chip microcomputer, receives the start, operation, throttle opening, parking and other instructions of the flight control system through the serial port, and completes the speed control of the motor 5 through the drive circuit according to the speed, throttle and load curve of the piston engine, simulating the actual working state of the engine.

[0039] The sensor simulation terminal 2 reads the piston engine mathematical model through the serial port, and simulates the cylinder head temperature, intake pressure, fuel pressure and other information of the piston engine by means of a signal source through conditions such as rotation speed, throttle opening, heat dissipation, etc., so as to meet the collection of engine information by the piston engine mathematical model.

[0040] The fault injection terminal 3 injects and simulates faults on the sensor information, oil circuit, air intake, etc. of the engine by pressing buttons and combining discrete quantities with continuous quantities.

[0041] The data acquisition terminal 4 collects the speed signal of the motor 5 and the opening signal of the throttle servo 7, and feeds the collected data back to the flight control system to correct or simulate the response of the engine under different load conditions and form a closed-loop control of the flight control on the engine.

[0042] The present invention provides a piston engine simulation system for an unmanned helicopter. There are many methods and ways to implement the technical solution. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be considered as the protection scope of the present invention. All components not specified in this embodiment can be implemented by existing technologies.

Claims

1. A piston engine simulation system for unmanned helicopters, It is characterized in that It comprises a piston engine simulation control terminal (1), a sensor simulation terminal (2), a fault injection terminal (3), a data acquisition terminal (4), a motor (5), a torque load device (6) and a throttle steering gear (7); The piston engine simulation control terminal (1) controls the motor (5), the torque load device (6) and the throttle steering gear (7) according to the flight control system instruction, through the engine temperature and pressure data of the sensor simulation terminal (2) and the engine fault state simulation data set by the fault injection terminal (3), so as to simulate the real running state of the engine, and collects the information of the motor and the throttle steering gear through the data acquisition terminal (4) and transmits it back to the flight control system; The control voltage U of the motor (5) t Written as follows: Among them, k 0 is the proportional constant, N 0 is the target speed, N t Current speed, U N is the nominal voltage, I 0 is the no-load current, n 0 is the no-load speed, R is the terminal resistance; The control voltage U of the torque load device (6) t ′ for: Among them, K 0 is the control constant of the torque load device (6), M 0 is the rated torque, the updated speed N t ′ =k 1 N t f(t), k 1 is the transmission ratio coefficient, f(t) is the piston engine data model table; the control equation of the motor in the system is modified to: U=U t + ST t ′ Where K is the torque coefficient of the motor and the torque load.

2. The system according to claim 1, It is characterized in that A matching motor control algorithm and control software are designed based on the voltage-speed curve, speed-load curve and mechanical time constant of the motor (5). The motor (5) is controlled to rotate through a drive module and the control parameters of the torque load device (6) are corrected based on the real-time feedback data of the motor (5) speed, so as to simulate the operation of the engine and the load and throttle relationship response under constant speed conditions, so as to simulate, emulate and correct the accuracy of the engine control by the flight control software of the unmanned helicopter.

3. The system according to claim 2, It is characterized in that The piston engine simulation control terminal (1) includes an embedded motor control unit and an engine throttle load data model, and controls the motor voltage and the control voltage of the torque load device according to the embedded engine throttle load data model and the mechanical time constant and speed load curve of the rear-end motor (5) by designing a software algorithm and a control method.

4. The system according to claim 3, It is characterized in that The sensor simulation terminal (2) simulates the engine intake pressure and cylinder head temperature information under different speed conditions according to the engine model; The fault injection terminal (3) simulates fault injection into the signals of various sensors of the engine by pressing keys, so as to test the reaction state of the engine under various faults; The data acquisition terminal (4) acquires the rotation speed signal of the motor (5) and the opening signal of the throttle steering gear (7), and feeds back the acquired data to the flight control system, thereby forming a closed-loop control of the engine by the flight control system.

5. The system according to claim 4, It is characterized in that The piston engine simulation control terminal (1) adopts a single-chip microcomputer embedded with a piston engine control model, and according to the instructions of the flight control system, realizes that under different working conditions of the unmanned helicopter, according to different set loads, the simulated control voltage of the motor (5) under different working conditions is calculated and corrected, thereby simulating the response of the engine under actual working conditions.

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