Ignition reverse thrust deceleration landing system for recoverable rocket

Abstract

The invention relates to the field of rocket recovery, in particular to an ignition reverse thrust deceleration landing system for a recoverable rocket, which designs a reverse thrust engine module, defines a propellant and a plurality of parameters, perfects a fuel supply system, and covers solutions to storage, vaporization, collapse, vortexes and other problems. According to the accurate control algorithm, the trajectory and speed of a rocket are predicted through multi-sensor data, a reverse thrust engine is dynamically adjusted through complex steps including target setting, control strategy, ignition, thrust adjustment and the like, and real-time feedback and landing stage control are further achieved. The integrated sensor system comprises various types of sensors and is responsible for collecting and processing data and transmitting the data to the control system. System integration involves hardware, software and debugging, and test plans include ground, simulation and flight testing. The safety and redundancy design comprises a redundancy control path, a fault detection mechanism and countermeasures when an engine and a sensor have faults. According to the scheme, the rocket recovery accuracy and safety can be improved, and the cost is reduced.

Description

Technical Field

[0001] The invention relates to the field of rocket recovery, and in particular to a recyclable rocket landing system using ignition reverse thrust to decelerate. Background Art

[0002] Rocket recovery refers to the technical process of recycling part or all of a rocket's components for reuse after the rocket launch mission is completed; recycled rockets can reuse key components such as engines and rocket bodies, thereby significantly reducing the cost of rocket manufacturing. When a rocket can be recovered and quickly refurbished for reuse, the rocket production cycle can be shortened.

[0003] In the parachute recovery rocket method, after completing the mission, the rocket releases a parachute to increase air resistance, thereby reducing the descent speed and achieving the recovery landing of the rocket.

[0004] The drawback is that the control effect of the parachute system on the rocket's attitude depends largely on environmental conditions. For example, in strong winds or unstable weather conditions, the parachute system may not be able to effectively control the rocket's attitude, and may even cause the rocket to lose control. In addition, the aerodynamic characteristics of the parachute system will change at different altitudes and atmospheric conditions, which will also affect the control effect of the rocket's attitude. Summary of the invention

[0005] The present invention provides a recyclable rocket ignition reverse thrust deceleration landing system, and the technical problem to be solved is: how to accurately control the reverse thrust to achieve a soft landing of the rocket.

[0006] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0007] The recyclable rocket ignition reverse thrust deceleration landing system is characterized by comprising a reverse thrust engine, an inertial measurement unit, a GPS module and an altimeter, and a Kalman filter;

[0008] The reverse thrust engine is installed inside the rocket body;

[0009] The inertial measurement unit contains an accelerometer and a gyroscope; it is used to measure the acceleration of the rocket in three axes, and the gyroscope measures the angular velocity of the rocket;

[0010] The GPS positioning module determines the rocket's own position by receiving satellite signals;

[0011] An altimeter is used to measure the height of a rocket relative to the ground;

[0012] The velocity sensor is used to measure the speed of the rocket;

[0013] The Kalman filter obtains data from the IMU, GPS, and altimeter and determines the rocket's current position, velocity, and acceleration. Based on the rocket's dynamic model, it predicts the trajectory and velocity at the next moment and uses sensor data to correct the predicted values ​​to obtain a more accurate state estimate.

[0014] Set the coordinates of the target landing point and target landing speed and dynamically adjust the ignition time and thrust output;

[0015] Adjust the ignition timing and thrust output of the thrust reverser engines;

[0016] Real-time feedback and adjustment of the real-time status of the rocket;

[0017] When approaching the ground, the thrust of the reverse thrust engine is precisely controlled to gradually reduce the rocket's descent speed, and the attitude control system is used to ensure that the rocket maintains a vertical attitude when landing.

[0018] Furthermore, the coordinates of the target landing point and the target landing speed are set, and the ignition time and thrust output are dynamically adjusted; specifically: (1) the coordinates of the target landing point and the target landing speed are set; (2) a PID controller is used to adjust the thrust, the error between the current position of the rocket and the target position is calculated to generate a position control signal, and the error between the current speed of the rocket and the target speed is calculated to generate a speed control signal; at the same time, model predictive control is used to optimize the thrust output in the future based on the predicted trajectory and speed, the future state is predicted using the dynamic model of the rocket, and the optimal thrust output is found through the optimization algorithm, so that the rocket is as close to the target state as possible in the future.

[0019] Furthermore, the ignition time and thrust output of the reverse thrust engine are adjusted; specifically: (1) the optimal ignition time of the reverse thrust engine is determined according to the predicted trajectory and speed, the optimal ignition time window is calculated to ensure that the reverse thrust engine is started when the rocket is close to the ground, the thrust output is dynamically adjusted according to the real-time status and control signal, the thrust output is accurately controlled by using a thrust regulating valve or a variable thrust engine, and the thrust of each engine is reasonably distributed in a multi-engine configuration to ensure the stability of the rocket attitude.

[0020] Furthermore, the real-time status of the rocket is fed back and adjusted in real time; specifically: (1) Real-time monitoring: Continuously monitor the data of IMU, GPS and altimeter to obtain the real-time status of the rocket, and use the Kalman filter to update the state estimation of the rocket in real time; (2) Dynamic adjustment: Dynamically adjust the control strategy according to the error between the real-time status and the predicted value, introduce an adaptive algorithm in the controller, and automatically adjust the PID parameters or MPC weights to cope with environmental changes and uncertainties.

[0021] Further, redundant control paths and automatic fault detection mechanisms;

[0022] Design the main control path and backup control path, set up multi-level redundancy at key control nodes, and provide independent power supply for control systems and sensors;

[0023] Monitor the status of each subsystem in real time, including sensor data, engine status, and system temperature. Use advanced fault diagnosis algorithms to automatically detect and diagnose system faults. When a fault is detected, an alarm is immediately issued and the fault information is recorded.

[0024] Furthermore, the strategy for dealing with reverse thrust engine failure is as follows: multiple reverse thrust engines are designed. When one engine fails, the backup engine will immediately take over the work, and the thrust distribution algorithm will be used to reasonably distribute the thrust among multiple reverse thrust engines. When a serious failure of the reverse thrust engine is detected, the emergency landing procedure will be initiated. By adjusting the attitude and speed of the rocket, the impact force during landing can be minimized to protect the payload.

[0025] Furthermore, the sensor system failure response strategy; each key sensor is designed with multiple redundant sensors. When a sensor fails, the backup sensor immediately takes over the work. Data fusion technology is used to comprehensively process data from different sensors to improve the system's perception of the rocket status. Faulty sensors are quickly identified and isolated through fault isolation and reconstruction technology, and system resources are reconfigured at the same time to ensure the continuity and reliability of sensor data.

[0026] Furthermore, a buffer device is installed at the bottom of the rocket to absorb the impact force during landing, and a contact sensor is used to detect the contact between the rocket and the ground, so as to shut down the reverse thrust engine in time.

[0027] Furthermore, the fuel and oxidizer are stored in storage tanks, which are made of insulating materials and double-layer tanks; a pressure relief valve and a pump are installed, wherein the relief valve and the pump are used to keep the internal pressure of the tank within a safe range; a low-temperature cooling system is used to maintain the low temperature state of the liquid fuel and the oxidizer.

[0028] Furthermore, a boosting system is provided, which is used to maintain a stable pressure in the storage tank; prevent the liquid level from collapsing; add an anti-collapse plate or foam on the inner surface of the storage tank to inhibit liquid movement and vortex generation;

[0029] Anti-vortex sheets or anti-vortex nets are installed at the tank outlet to break up the vortex.

[0030] The beneficial effects of the present invention are:

[0031] Dynamic adjustment of the reverse thrust engine can be achieved to ensure that the rocket can land smoothly and accurately. This process requires highly integrated sensors, accurate state estimation, advanced control algorithms and real-time feedback mechanisms. DETAILED DESCRIPTION

[0032] In order to make the contents of the present invention more clearly understood, the technical solutions in the embodiments of the present invention are described clearly and completely.

[0033] The reusable rocket uses ignition reverse thrust to slow down the landing system, including reverse thrust engine, inertial measurement unit (IMU), GPS and altimeter, Kalman filter;

[0034] The reverse thrust engine, inertial measurement unit (IMU), GPS and altimeter, and Kalman filter are installed inside the rocket body;

[0035] The reverse thrust engine is used to provide reverse thrust during the rocket recovery process to slow down the rocket and achieve the recovery and landing of the rocket.

[0036] The Inertial Measurement Unit (IMU) contains accelerometers and gyroscopes. The accelerometers measure the acceleration of the rocket in three axes, and the gyroscopes measure the angular velocity of the rocket. These data are crucial to understanding the motion state of the rocket.

[0037] The GPS positioning module determines the rocket's own position by receiving satellite signals. During the rocket recovery process, GPS data can help accurately determine the rocket's position for trajectory prediction and control.

[0038] An altimeter is used to measure the height of a rocket relative to the ground.

[0039] The velocity sensor is used to measure the velocity of the rocket.

[0040] The Kalman filter obtains data from the IMU, GPS, and altimeter and determines the rocket's current position, speed, and acceleration; based on the rocket's dynamic model, it predicts the trajectory and speed at the next moment and uses sensor data to correct the predicted values ​​to obtain a more accurate state estimate.

[0041] Set the coordinates of the target landing point and the target landing speed, and dynamically adjust the ignition time and thrust output. Specifically: (1) Set the coordinates of the target landing point and the target landing speed (usually close to zero). (2) Use a PID controller to adjust the thrust, calculate the error between the current position of the rocket and the target position to generate a position control signal, and calculate the error between the current speed of the rocket and the target speed to generate a speed control signal; at the same time, use model predictive control (MPC) to optimize the thrust output in the future based on the predicted trajectory and speed, use the rocket's dynamic model to predict the future state, and find the optimal thrust output through the optimization algorithm to make the rocket as close to the target state as possible in the future.

[0042] Adjust the ignition time and thrust output of the reverse thrust engine. Specifically: (1) Determine the optimal ignition time of the reverse thrust engine based on the predicted trajectory and speed, calculate the optimal ignition time window to ensure that the reverse thrust engine is started when the rocket is close to the ground, dynamically adjust the thrust output based on the real-time status and control signal, use a thrust regulating valve or a variable thrust engine to accurately control the thrust output, and reasonably distribute the thrust of each engine in a multi-engine configuration to ensure the stability of the rocket attitude.

[0043] Real-time feedback and adjustment of the real-time status of the rocket. Specifically: (1) Real-time monitoring: Continuously monitor the data of IMU, GPS and altimeter to obtain the real-time status of the rocket, and use the Kalman filter to update the state estimation of the rocket in real time. (2) Dynamic adjustment: Dynamically adjust the control strategy according to the error between the real-time status and the predicted value, introduce an adaptive algorithm in the controller, and automatically adjust the PID parameters or MPC weights to cope with environmental changes and uncertainties.

[0044] When approaching the ground, the thrust of the reverse thrust engine is precisely controlled to gradually reduce the rocket's descent speed, and the attitude control system is used to ensure that the rocket maintains a vertical attitude when landing.

[0045] Through the above steps and algorithms, dynamic adjustment of the reverse thrust engine can be achieved to ensure that the rocket can land smoothly and accurately. This process requires highly integrated sensors, accurate state estimation, advanced control algorithms and real-time feedback mechanisms.

[0046] On the other hand, redundant control paths and automatic fault detection mechanisms.

[0047] Design the main control path and backup control path, set up multi-level redundancy at key control nodes, and provide independent power supply for control systems and sensors.

[0048] Monitor the status of each subsystem in real time, including sensor data, engine status, and system temperature. Use advanced fault diagnosis algorithms to automatically detect and diagnose system faults. When a fault is detected, an alarm is immediately issued and the fault information is recorded.

[0049] On the other hand, the strategy for dealing with reverse thrust engine failure is to design multiple reverse thrust engines. When one engine fails, the backup engine will immediately take over the work, and use the thrust distribution algorithm to reasonably distribute the thrust among multiple reverse thrust engines. When a serious failure of the reverse thrust engine is detected, the emergency landing procedure is initiated, and the impact force during landing is minimized by adjusting the attitude and speed of the rocket to protect the payload.

[0050] On the other hand, the sensor system failure response strategy; each key sensor is designed with multiple redundant sensors. When a sensor fails, the backup sensor immediately takes over the work. Data fusion technology is used to comprehensively process data from different sensors to improve the system's perception of the rocket status. Faulty sensors are quickly identified and isolated through fault isolation and reconstruction technology, and system resources are reconfigured at the same time to ensure the continuity and reliability of sensor data.

[0051] Furthermore, a buffer device is installed at the bottom of the rocket to absorb the impact force during landing, and a contact sensor is used to detect the contact between the rocket and the ground, so as to shut down the reverse thrust engine in time.

[0052] Furthermore, the fuel and oxidant are stored in a storage tank, which is made of thermal insulation material and double-layer storage tank to prevent heat conduction. A pressure relief valve and a pump are installed, wherein the relief valve and the pump are used to keep the internal pressure of the tank within a safe range. A cryogenic cooling system is used to maintain the low temperature state of the liquid fuel and oxidant.

[0053] Furthermore, a cooling system is used on the pipelines for transporting fuel and oxidant inside the tank to prevent evaporation caused by temperature rise during transportation. Effective insulation layers are designed on the above pipelines and valves to prevent external heat from entering. Gas-liquid separation equipment is set at key points in the pipeline to ensure that the material flowing into the combustion chamber is in liquid form.

[0054] Furthermore, a pressure boosting system is provided, which is used to maintain a stable pressure in the storage tank and prevent the liquid level from collapsing. Anti-collapse plates or foam are added to the inner surface of the storage tank to inhibit liquid movement and vortex generation.

[0055] Furthermore, anti-vortex sheets or anti-vortex nets are installed at the outlet of the storage tank to break up the vortex. The outlet of the storage tank is set to be a little rounded. The bottom of the storage tank is pulled out of the tube or multi-tube design to ensure that the liquid can be transported smoothly even in the case of vortex.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A reusable rocket ignition reverse thrust deceleration landing system, characterized in that: Includes reverse thrust engine, inertial measurement unit, GPS module and altimeter, Kalman filter; The reverse thrust engine is installed inside the rocket body; The inertial measurement unit contains an accelerometer and a gyroscope; it is used to measure the acceleration of the rocket in three axes, and the gyroscope measures the angular velocity of the rocket; The GPS positioning module determines the rocket's own position by receiving satellite signals; An altimeter is used to measure the height of a rocket relative to the ground; The velocity sensor is used to measure the speed of the rocket; The Kalman filter obtains data from the IMU, GPS, and altimeter and determines the rocket's current position, velocity, and acceleration. Based on the rocket's dynamic model, it predicts the trajectory and velocity at the next moment and uses sensor data to correct the predicted values ​​to obtain a more accurate state estimate. Set the coordinates of the target landing point and target landing speed and dynamically adjust the ignition time and thrust output; Adjust the ignition timing and thrust output of the thrust reverser engines; Real-time feedback and adjustment of the real-time status of the rocket; When approaching the ground, the thrust of the reverse thrust engine is precisely controlled to gradually reduce the rocket's descent speed, and the attitude control system is used to ensure that the rocket maintains a vertical attitude when landing.

2. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: The coordinates of the target landing point and the target landing speed are set, and the ignition time and thrust output are dynamically adjusted; specifically: (1) the coordinates of the target landing point and the target landing speed are set; (2) the thrust is adjusted using a PID controller, the error between the current position of the rocket and the target position is calculated to generate a position control signal, and the error between the current speed of the rocket and the target speed is calculated to generate a speed control signal; at the same time, model predictive control is used to optimize the thrust output in the future based on the predicted trajectory and speed, the future state is predicted using the dynamic model of the rocket, and the optimal thrust output is found through an optimization algorithm, so that the rocket is as close to the target state as possible in the future.

3. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: Adjust the ignition time and thrust output of the reverse thrust engine; specifically: (1) determine the optimal ignition time of the reverse thrust engine based on the predicted trajectory and speed, calculate the optimal ignition time window to ensure that the reverse thrust engine is started when the rocket is close to the ground, dynamically adjust the thrust output based on the real-time status and control signal, use a thrust regulating valve or a variable thrust engine to accurately control the thrust output, and reasonably distribute the thrust of each engine in a multi-engine configuration to ensure the stability of the rocket's attitude.

4. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: Real-time feedback and adjustment of the real-time status of the rocket; specifically: (1) Real-time monitoring: Continuously monitor the data of IMU, GPS and altimeter to obtain the real-time status of the rocket, and use the Kalman filter to update the state estimation of the rocket in real time; (2) Dynamic adjustment: Dynamically adjust the control strategy according to the error between the real-time status and the predicted value, introduce an adaptive algorithm in the controller, and automatically adjust the PID parameters or MPC weights to cope with environmental changes and uncertainties.

5. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: Redundant control paths and automatic fault detection mechanisms; Design the main control path and backup control path, set up multi-level redundancy at key control nodes, and provide independent power supply for control systems and sensors; Monitor the status of each subsystem in real time, including sensor data, engine status, and system temperature. Use advanced fault diagnosis algorithms to automatically detect and diagnose system faults. When a fault is detected, an alarm is immediately issued and the fault information is recorded.

6. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: Strategy for dealing with reverse thrust engine failure: Design multiple reverse thrust engines. When one engine fails, the backup engine will immediately take over the work. Use the thrust distribution algorithm to reasonably distribute the thrust among multiple reverse thrust engines. When a serious failure of the reverse thrust engine is detected, initiate the emergency landing procedure. By adjusting the attitude and speed of the rocket, minimize the impact force during landing and protect the payload.

7. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: Sensor system failure response strategy: Each key sensor is designed with multiple redundant sensors. When a sensor fails, the backup sensor immediately takes over the work. Data fusion technology is used to comprehensively process data from different sensors to improve the system's perception of the rocket's status. Faulty sensors are quickly identified and isolated through fault isolation and reconstruction technology, and system resources are reconfigured at the same time to ensure the continuity and reliability of sensor data.

8. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: A buffer device is installed at the bottom of the rocket to absorb the impact force during landing, and a contact sensor is used to detect the contact between the rocket and the ground, and the reverse thrust engine is shut down in time.

9. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: The fuel and oxidizer are stored in storage tanks, which are made of insulating materials and double-layer tanks; pressure relief valves and pumps are installed, wherein the relief valves and pumps are used to keep the internal pressure of the tanks within a safe range; a low-temperature cooling system is used to maintain the low temperature state of the liquid fuel and oxidizer.

10. The recyclable rocket ignition reverse thrust deceleration landing system according to claim 1, characterized in that: A booster system is provided, which is used to maintain a stable pressure in the storage tank; prevent the liquid level from collapsing; add an anti-collapse plate or foam on the inner surface of the storage tank to inhibit liquid movement and vortex generation; Anti-vortex sheets or anti-vortex nets are installed at the tank outlet to break up the vortex.