Vertical take-off and landing reusable aircraft power configuration and closed loop control method thereof

Abstract

The vertical take-off and landing reusable aircraft power configuration and the closed-loop control method thereof disclosed by the application comprise a main engine, four traveling machines and a five-machine parallel large rack, the main engine is arranged at the center of the five-machine parallel large rack, the four traveling machines are arranged uniformly around the main engine on the five-machine parallel large rack, and the main engine and the four traveling machines are further communicatively connected with a closed-loop control system. The application has the beneficial effect of realizing automatic and undisturbed switching of multiple working conditions through high and speed double thresholds, which is different from the traditional single control mode, and can dynamically allocate the working authority and thrust ratio of the main engine and the traveling machine within the whole task profile; the overload, attitude, speed and height multi-loop coupling control law is constructed, the priority control closed loop of different stages is adapted, and the fault redundancy and reconstruction are realized relying on the symmetrical layout of the four traveling machines, which realizes the precise and stable control of the whole process, and greatly improves the vertical take-off and landing task adaptability and flight reliability.

Description

Technical Field

[0001] This invention belongs to the field of liquid rocket technology, and relates to the propulsion configuration of vertical takeoff and landing reusable aircraft, as well as a closed-loop control method for the propulsion configuration of vertical takeoff and landing reusable aircraft. Background Technology

[0002] SpaceX, using its Falcon 9 rocket, has achieved vertical takeoff, landing, and reuse of its first stage, effectively reducing the cost of satellite launches, improving launch efficiency, and securing a dominant position in the European and American rocket launch markets. The Falcon 9's first stage is powered by nine Merlin engines in parallel, achieving vertical landing through multiple ignitions of three engines and continuous thrust variation of the middle engine. BlueOrigin's New Shepard suborbital crewed tourism rocket uses a single BE-3 hydrogen-oxygen engine with a thrust variation range of 5.5:1, enabling suborbital vertical takeoff, landing, and reuse. This propulsion configuration requires fewer engines, has a simpler propulsion system, and is lower in cost, but it demands a wide thrust variation range. For pump-jet main engines, achieving this range is challenging and time-consuming. Apart from the low-thrust, squeeze-type variable-thrust engine used in lunar probes, domestically produced pump-jet main engines have not yet reached this thrust variation range.

[0003] Currently, many reusable launch vehicles planned in China are based on the Falcon 9 configuration. The first stage of this rocket has nine engines (one in the center and eight in the outer ring), with the center engine having a thrust-to-weight ratio of 2:1, which is sufficient for vertical takeoff, landing, and return. While this first-stage power configuration has lower requirements for the thrust-to-weight ratio of the engines, the large number of engines connected in parallel in the first stage leads to a more complex power transmission structure and pipelines, resulting in an exponential decrease in rocket reliability and a significant increase in the development cost of the first stage.

[0004] Therefore, for the power configuration of reusable vertical takeoff and landing aircraft, it is necessary to explore a new solution from the perspectives of reducing costs and scale and lowering development difficulty, so as to reduce the development cost of the power system and meet the launch requirements of flight operations. Summary of the Invention

[0005] The first objective of this invention is to provide a power configuration for a vertical takeoff and landing reusable aircraft, which solves the problems of excessive number of parallel first-stage rocket engines, complex force transmission structures and pipelines, and reduced reliability in the prior art.

[0006] A second objective of this invention is to provide a closed-loop control method for the power configuration of a vertical takeoff and landing reusable aircraft.

[0007] The first technical solution adopted in this invention is a vertical takeoff and landing reusable aircraft power configuration, including a main engine, four cruisers and a five-engine parallel frame. The main engine is located at the center of the five-engine parallel frame, and the four cruisers are evenly arranged around the main engine on the five-engine parallel frame. The main engine and the four cruisers are also connected to a closed-loop control system.

[0008] The invention is further characterized by: The five-machine parallel large frame includes an upper end face, a lower end face, and eight V-shaped support force transmission rods; the upper end face is a regular octagonal frame with eight vertex joints; the lower end face is a square frame with four vertices and four midpoints of the sides, with the midpoints of the sides located at the middle of each side; the upper end face and the lower end face are connected by V-shaped support force transmission rods.

[0009] The V-shaped support force transmission rod is formed by two connecting rods rigidly intersecting at a bend point. The two free ends of each V-shaped support force transmission rod are rigidly connected to two adjacent vertices on the regular octagonal frame, and the bend point of each V-shaped support force transmission rod is rigidly connected to the square frame. The bend points of multiple V-shaped support force transmission rods are continuously arranged along the circumference of the square frame and are alternately connected to the vertices and midpoints of the sides of the square frame. The four midpoints of the sides of the square frame are fixedly connected to cross beams. The main engine includes a thrust chamber and a constant level seat structure. One end of the constant level seat structure is fixedly connected to the top of the thrust chamber by bolts, and the other end of the constant level seat structure is fixedly installed at the center of the bottom of the cross beam of the five-engine parallel frame by bolts. Each of the four mobile units is equipped with a thrust chamber and a constant level seat structure. The thrust chamber of each mobile unit is connected to the corresponding constant level seat structure by bolts. The other end of each constant level seat structure is fixedly connected to the bottom center of the four vertices of the square frame of the five-unit parallel machine frame by bolts.

[0010] A thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of the main engine, and a thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of each of the four vernier engines; the main engine and each vernier engine are independently equipped with a servo mechanism, and each servo mechanism includes a servo cylinder trunnion and a servo piston rod. The bottom of the cross beam is also fixed with a support. The servo mechanism of the main engine is hinged to the support at the bottom of the cross beam of the five-machine parallel frame through a pin. The square frame is also fixed with four supports. The servo mechanism of each of the four mobile engines is hinged to the support at the bottom of the square frame of the five-machine parallel frame through a pin. The servo piston rods of the main engine and each mobile engine are all hinged to the thrust chamber swing support of the corresponding main engine or mobile engine via pins.

[0011] It also includes liquid oxygen delivery pipelines and fuel delivery pipelines. One end of the liquid oxygen delivery pipeline is connected to a liquid oxygen storage tank, and the other end of the liquid oxygen delivery pipeline is connected to the liquid oxygen inlet of the main engine and the liquid oxygen inlet of the four mobile engines, respectively. One end of the fuel delivery pipeline is connected to a fuel storage tank, and the other end of the fuel delivery pipeline is connected to the fuel inlet of the main engine and the fuel inlet of the four mobile engines, respectively.

[0012] The liquid oxygen delivery pipeline includes a spherical six-way structure, which has one inlet and five outlets. The inlet of the spherical six-way structure is connected to the liquid oxygen tank of the aircraft, and the five outlets of the spherical six-way structure are respectively connected to the liquid oxygen inlets of the main engine and the four cruise engines. The fuel delivery pipeline includes the main engine fuel delivery pipeline and the cruise aircraft fuel delivery pipeline. One end of the main engine fuel delivery pipeline is connected to the fuel tank, and the other end is connected to the main engine fuel inlet. The cruise aircraft fuel delivery pipeline includes a spherical five-way structure, which includes one inlet and four outlets. The inlet of the spherical five-way structure is connected to the aircraft's fuel tank, and the four outlets are respectively connected to the fuel inlets of the four cruise aircraft.

[0013] The main engine uses a gas generator circulation system, and all four turbines are powered by electric pumps.

[0014] The closed-loop control system includes a mission profile planning and main control module, a multivariable coupled closed-loop control law module, a thrust distribution and servo control module, a modal decision and switching control unit, a modal class module, a multi-source sensing module, and a redundancy fault-tolerant and fault reconstruction control unit. The multi-source sensing module, modal decision and switching control unit, modal class module, redundancy fault-tolerant and fault reconstruction control unit, mission profile planning and main control module, multivariable coupled closed-loop control law module, and thrust distribution and servo control module are interconnected.

[0015] The mission profile planning and main control module pre-stores core thresholds for start-up, shutdown, secondary ignition of the main and wandering engines, secondary shutdown of the main and wandering engines, as well as altitude, speed, overload, dynamic pressure, attitude, servo position, thrust, and working condition switching for each stage. The multivariable coupled closed-loop control law module is used to automatically switch the coupled control strategy according to the core control objectives of different modes, and automatically switch the control outer loop at different stages. The attitude outer loop is used during takeoff and landing, the overload outer loop is used during climb, and the speed outer loop is used during deceleration, so as to adapt to the full mission profile conditions. The thrust distribution and servo control module is used to execute the control commands output by the multivariable coupled closed-loop control law module, control the ignition and shutdown of the main engine and four vernier engines, and linearly control the thrust of the main engine and four vernier engines; at the same time, it controls the servo mechanisms of the main engine and four vernier engines to actuate the nozzle vector deflection, so that the aircraft maintains the required attitude. The mode decision and switching control unit is used to determine the current mission phase and switch to the corresponding control mode. At the mode switching node, the mode decision and switching control unit determines the mode of the aircraft through dual thresholds of speed and altitude, and switches to a smooth transition algorithm to accurately switch modes. The modal modules include six modes: vertical takeoff, climb load limit, inertial taxiing, reentry trim, active deceleration, and soft landing. Based on the control of the modal decision and switching control unit, different modal control multivariable coupled closed-loop control law modules are used accordingly. The multi-source sensing module is used to collect real-time data on aircraft altitude, speed, overload, attitude, engine thrust, and servo position. The redundancy-tolerant and fault reconstruction control unit is used to detect the fault status of the main engine and four vernier engines. When a fault occurs in the main engine or vernier engine, it immediately performs thrust reconstruction and redistribution of thrust between the main engine and vernier engines, and compensates for the deviation by symmetrically adjusting the non-faulty engines.

[0016] The second technical solution adopted in this invention, a closed-loop control method for the power configuration of a vertical takeoff and landing reusable aircraft, includes the following steps: Step 1: The multi-source sensor module collects various data from the aircraft in real time and transmits them synchronously to the mode decision and switching control unit and the redundancy fault tolerance and fault reconstruction control unit. Step 2: The modal decision and switching control unit determines the current task stage and switches the corresponding control mode based on the data collected by the multi-source sensor module, the task profile planning, and the data pre-stored in the main control module. Step 3: The multivariable coupled closed-loop control law module automatically switches the coupled control strategy according to the core control objective of the corresponding control mode to complete the flight mission.

[0017] The beneficial effects of this invention are: 1. Compared to the Falcon 9's single-stage, nine-engine parallel power configuration, this invention requires only one main engine and four small-thrust propellers, resulting in lower overall power system costs and making it easier to achieve vertical takeoff and landing (VTOL) flights at speeds of up to 100 kilometers with relatively low development costs. Furthermore, the small thrust ratio of the small-thrust engines (2:1) allows for a wide range of total thrust variations, with the maximum ratio exceeding 9:1. This enables the aircraft to hover during return landing, significantly reducing the difficulty of high-altitude return landings and increasing the success rate of reuse.

[0018] 2. Compared to Blue Origin's New Shepard suborbital vehicle, which uses a single variable-thrust engine, this design significantly reduces the thrust range requirement for the main engine to achieve suborbital vertical flight. For example, the New Shepard's BE-3 hydrogen-oxygen engine has a thrust range of 5.5:1, while this design only requires a thrust range of 70% to 100%. The small thrust variation is mainly used to reduce flight overload during ascent and high-altitude deceleration. This thrust range places lower requirements on the main engine's combustion components, eliminating the need to develop injectors specifically adapted to a wide thrust range. This results in a wider range of main engine options and significantly reduced development costs.

[0019] 3. Compared to existing vertical takeoff and landing (VTOL) aircraft power schemes in China, which utilize a single main engine for low-altitude VTOL flight tests, the limited thrust range of the main engine (approximately 2:1) results in a larger final landing mass, leading to less propellant consumption and lower flight altitudes, typically 10 kilometers or lower. This invention, using a combination of a main engine and four vernier engines, achieves a wider range of total thrust (exceeding 9:1), with less remaining propellant. The VTOL aircraft can reach altitudes of hundreds of kilometers. Furthermore, the continuous thrust variation of the four vernier engines ensures a smooth landing process, minimizes the impact of engine plumes, and enhances reliability.

[0020] 4. The five-engine parallel large frame of this invention adopts a centrally symmetrical layout and a space truss structure to achieve rigid connection of each power module. Compared with the traditional plate beam frame, it has a higher strength-to-weight ratio, can significantly reduce weight, and can uniformly transmit thrust and vibration loads, avoiding local stress concentration. This ensures both uniform power output and vertical takeoff and landing attitude stability, while also improving structural fatigue life, meeting the requirements of lightweight reusable aircraft and multiple takeoffs and landings. The supporting oxygen and fuel delivery system adopts a symmetrical distributed layout, with pipelines integrated along the truss members to achieve structure-pipeline integration. The centrally symmetrical flow channel of the spherical multi-pass structure can also ensure uniform fluid distribution and consistent thrust for multiple parallel engines, achieving the same effect as the large... The frame is well-integrated and adapted; at the same time, the large frame and the delivery pipeline achieve a deep coupling with a symmetrical layout. The spherical multi-port is coaxial with the frame center, and the pipeline is precisely connected to the circumferential power module, so that the force transmission path of the frame coincides with the flow channel of the pipeline. This achieves the coordinated bearing of structural load and fluid load, breaking through the traditional paradigm of independent layout of aircraft structure and pipeline. It effectively solves the thrust deviation problem caused by uneven flow field in multi-aircraft parallel operation, further improves the consistency of thrust output and vertical take-off and landing attitude control accuracy, and reduces the adjustment burden of flight control system. The overall integrated design and symmetrical load distribution also further enhance the system weight reduction effect and structural fatigue life, fully adapting to the usage requirements of reusable aircraft.

[0021] 5. The closed-loop control system of this invention innovatively adopts an integrated control architecture of multimodal hierarchical collaboration, multivariable coupled closed loop, and thrust-free handover. It achieves automatic and seamless switching between multiple operating conditions such as takeoff, climb, inertial taxiing, reentry deceleration, and soft landing through dual thresholds of altitude and speed. Unlike the traditional single control mode, it can dynamically allocate the working authority and thrust ratio of the main engine and the vernier in the entire mission profile. At the same time, it constructs multi-loop coupled control laws of overload, attitude, speed, and altitude to adapt to the priority control closed loops of different stages. It also relies on the symmetrical layout of four verniers to achieve fault redundancy and reconfiguration. While achieving precise and stable control throughout the entire process, it significantly improves the adaptability and flight reliability of vertical takeoff and landing missions at the 100-kilometer level. Attached Figure Description

[0022] Figure 1 This is a top-view three-dimensional structural diagram of the power configuration of the vertical take-off and landing reusable aircraft of the present invention; Figure 2 This is a front-view three-dimensional structural schematic diagram of the power configuration of the vertical take-off and landing reusable aircraft of the present invention; Figure 3 This is a three-dimensional structural diagram of the five-aircraft parallel large frame of the vertical take-off and landing reusable aircraft power configuration of the present invention; Figure 4 This is a three-dimensional structural schematic diagram of the fuel delivery pipeline of the vertical take-off and landing reusable aircraft power configuration of the present invention; Figure 5 This is a three-dimensional structural schematic diagram of the liquid oxygen delivery pipeline in the vertical take-off and landing reusable aircraft power configuration of the present invention; Figure 6 This is a flowchart of the closed-loop control method for the power configuration of a vertical takeoff and landing reusable aircraft according to the present invention; Figure 7 This is a schematic cross-sectional view of the flight mission of the vertical takeoff and landing reusable aircraft according to Embodiment 7 of the present invention; Figure 8 This is the altitude change curve of the vertical takeoff and landing reusable aircraft in Embodiment 7 of the present invention; Figure 9 This is the speed variation curve of the vertical takeoff and landing reusable aircraft in Embodiment 7 of the present invention; Figure 10 This is the overload variation curve of the vertical takeoff and landing reusable aircraft in Embodiment 7 of the present invention; Figure 11 This is the thrust adjustment process curve of the vertical takeoff and landing reusable aircraft engine in Embodiment 7 of the present invention; Figure 12 This is the total thrust variation curve of the vertical takeoff and landing reusable aircraft in Embodiment 7 of the present invention.

[0023] In the diagram, 1. Main engine, 2. Floating engine, 3. Five-engine parallel frame, 31. Upper end face, 32. Lower end face, 33. V-shaped support force transmission rod, 4. Main engine fuel delivery pipeline, 5. Floating engine fuel delivery pipeline, 51. Spherical five-way structure, 6. Spherical six-way structure. Detailed Implementation

[0024] The following detailed description is provided in conjunction with the accompanying drawings and specific embodiments.

[0025] Example 1 Vertical takeoff and landing reusable aircraft power configurations, such as Figure 1 As shown, it includes a main engine 1, four mobile engines 2 and a five-engine parallel frame 3. The main engine 1 is located at the center of the five-engine parallel frame 3, and the four mobile engines 2 are evenly arranged around the main engine 1 on the five-engine parallel frame 3. The main engine 1 and the four mobile engines 2 are also connected to a closed-loop control system.

[0026] Example 2 The power configuration of the vertical takeoff and landing reusable aircraft includes a main engine 1, four cruisers 2, and a five-aircraft parallel frame 3. The main engine 1 is located at the center of the five-aircraft parallel frame 3, and the four cruisers 2 are evenly distributed around the main engine 1 on the five-aircraft parallel frame 3. The main engine 1 and the four cruisers 2 are also connected to a closed-loop control system.

[0027] like Figure 3 As shown, the five-machine parallel large frame 3 includes an upper end face 31, a lower end face 32, and eight V-shaped support force transmission rods 33; the upper end face 31 is a regular octagonal frame with eight vertex joints; the lower end face 32 is a square frame with four vertices and four midpoints of the sides, with the midpoints of the sides located at the middle of each side; the upper end face 31 and the lower end face 32 are connected by the V-shaped support force transmission rods 33.

[0028] The V-shaped support force transmission rod 33 is formed by two connecting rods rigidly intersecting at a bend point. The two free ends of each V-shaped support force transmission rod 33 are rigidly connected to two adjacent vertices on the regular octagonal frame, and the bend point of each V-shaped support force transmission rod 33 is rigidly connected to the square frame. The bend points of multiple V-shaped support force transmission rods 33 are continuously arranged along the circumference of the square frame and are alternately connected to the vertices and midpoints of the sides of the square frame. Cross beams are fixedly connected to the midpoints of the four sides of the square frame. The main engine 1 includes a thrust chamber and a constant level seat structure. One end of the constant level seat structure is fixedly connected to the top of the thrust chamber by bolts, and the other end of the constant level seat structure is fixedly installed at the center of the bottom of the cross beam of the five-machine parallel large frame 3 by bolts. Each of the four mobile units 2 is equipped with a thrust chamber and a constant level seat structure. The thrust chamber of each mobile unit 2 is connected to the corresponding constant level seat structure by bolts. The other end of each constant level seat structure is fixedly connected to the bottom center of the four vertices of the square frame of the five-machine parallel large frame 3 by bolts.

[0029] Example 3 The power configuration of the vertical takeoff and landing reusable aircraft includes a main engine 1, four cruisers 2, and a five-aircraft parallel frame 3. The main engine 1 is located at the center of the five-aircraft parallel frame 3, and the four cruisers 2 are evenly distributed around the main engine 1 on the five-aircraft parallel frame 3. The main engine 1 and the four cruisers 2 are also connected to a closed-loop control system.

[0030] The five-machine parallel large frame 3 includes an upper end face 31, a lower end face 32, and eight V-shaped support force transmission rods 33; the upper end face 31 is a regular octagonal frame with eight vertex joints; the lower end face 32 is a square frame with four vertices and four midpoints of the sides, with the midpoints of the sides located at the middle of each side; the upper end face 31 and the lower end face 32 are connected by the V-shaped support force transmission rods 33.

[0031] The V-shaped support force transmission rod 33 is formed by two connecting rods rigidly intersecting at a bend point. The two free ends of each V-shaped support force transmission rod 33 are rigidly connected to two adjacent vertices on the regular octagonal frame, and the bend point of each V-shaped support force transmission rod 33 is rigidly connected to the square frame. The bend points of multiple V-shaped support force transmission rods 33 are continuously arranged along the circumference of the square frame and are alternately connected to the vertices and midpoints of the sides of the square frame. Cross beams are fixedly connected to the midpoints of the four sides of the square frame. The main engine 1 includes a thrust chamber and a constant level seat structure. One end of the constant level seat structure is fixedly connected to the top of the thrust chamber by bolts, and the other end of the constant level seat structure is fixedly installed at the center of the bottom of the cross beam of the five-machine parallel large frame 3 by bolts. Each of the four mobile units 2 is equipped with a thrust chamber and a constant level seat structure. The thrust chamber of each mobile unit 2 is connected to the corresponding constant level seat structure by bolts. The other end of each constant level seat structure is fixedly connected to the bottom center of the four vertices of the square frame of the five-machine parallel large frame 3 by bolts.

[0032] A thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of the main engine 1, and a thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of each of the four vernier engines 2. The main engine 1 and each vernier engine 2 are independently equipped with a set of servo mechanisms. Each set of servo mechanisms includes a servo cylinder trunnion and a servo piston rod. That is, the main engine 1 corresponds to a set of servo mechanisms, and each vernier engine 2 corresponds to an independent set of servo mechanisms. Each servo mechanism does not interfere with each other and works independently.

[0033] The bottom of the cross beam is also fixed with a support. The servo mechanism of the main engine 1 is connected to the servo cylinder trunnion of the servo mechanism through a pin and hinged to the support at the bottom of the cross beam of the five-machine parallel large frame 3. The square frame is also fixed with four supports. The servo mechanism of the four mobile engines 2 is connected to the servo cylinder trunnion of the four mobile engines through a pin and hinged to the support at the bottom of the square frame of the five-machine parallel large frame 3. The servo mechanisms of the main engine 1 and each motor 2 are equipped with servo piston rods that are hinged to the thrust chamber swing support of the corresponding main engine 1 or motor 2 via pins; this enables the servo mechanism to be connected to the corresponding engine and the five-engine parallel frame 3, ensuring that each engine can be independently controlled through its own servo mechanism.

[0034] Example 4 The power configuration of the vertical takeoff and landing reusable aircraft includes a main engine 1, four cruisers 2, and a five-aircraft parallel frame 3. The main engine 1 is located at the center of the five-aircraft parallel frame 3, and the four cruisers 2 are evenly distributed around the main engine 1 on the five-aircraft parallel frame 3. The main engine 1 and the four cruisers 2 are also connected to a closed-loop control system.

[0035] The five-machine parallel large frame 3 includes an upper end face 31, a lower end face 32, and eight V-shaped support force transmission rods 33; the upper end face 31 is a regular octagonal frame with eight vertex joints; the lower end face 32 is a square frame with four vertices and four midpoints of the sides, with the midpoints of the sides located at the middle of each side; the upper end face 31 and the lower end face 32 are connected by the V-shaped support force transmission rods 33.

[0036] The V-shaped support force transmission rod 33 is formed by two connecting rods rigidly intersecting at a bend point. The two free ends of each V-shaped support force transmission rod 33 are rigidly connected to two adjacent vertices on the regular octagonal frame, and the bend point of each V-shaped support force transmission rod 33 is rigidly connected to the square frame. The bend points of multiple V-shaped support force transmission rods 33 are continuously arranged along the circumference of the square frame and are alternately connected to the vertices and midpoints of the sides of the square frame. Cross beams are fixedly connected to the midpoints of the four sides of the square frame. The main engine 1 includes a thrust chamber and a constant level seat structure. One end of the constant level seat structure is fixedly connected to the top of the thrust chamber by bolts, and the other end of the constant level seat structure is fixedly installed at the center of the bottom of the cross beam of the five-machine parallel large frame 3 by bolts. Each of the four mobile units 2 is equipped with a thrust chamber and a constant level seat structure. The thrust chamber of each mobile unit 2 is connected to the corresponding constant level seat structure by bolts. The other end of each constant level seat structure is fixedly connected to the bottom center of the four vertices of the square frame of the five-machine parallel large frame 3 by bolts.

[0037] A thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of the main engine 1, and a thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of each of the four vernier engines 2. The main engine 1 and each vernier engine 2 are independently equipped with a set of servo mechanisms. Each set of servo mechanisms includes a servo cylinder trunnion and a servo piston rod. That is, the main engine 1 corresponds to a set of servo mechanisms, and each vernier engine 2 corresponds to an independent set of servo mechanisms. Each servo mechanism does not interfere with each other and works independently.

[0038] The bottom of the cross beam is also fixed with a support. The servo mechanism of the main engine 1 is connected to the servo cylinder trunnion of the servo mechanism through a pin and hinged to the support at the bottom of the cross beam of the five-machine parallel large frame 3. The square frame is also fixed with four supports. The servo mechanism of the four mobile engines 2 is connected to the servo cylinder trunnion of the four mobile engines through a pin and hinged to the support at the bottom of the square frame of the five-machine parallel large frame 3. The servo mechanisms of the main engine 1 and each motor 2 are equipped with servo piston rods that are hinged to the thrust chamber swing support of the corresponding main engine 1 or motor 2 via pins; this enables the servo mechanism to be connected to the corresponding engine and the five-engine parallel frame 3, ensuring that each engine can be independently controlled through its own servo mechanism.

[0039] like Figure 2 , Figure 4 , Figure 5 As shown, it also includes a liquid oxygen delivery pipeline and a fuel delivery pipeline. One end of the liquid oxygen delivery pipeline is connected to a liquid oxygen storage tank, and the other end of the liquid oxygen delivery pipeline is connected to the liquid oxygen inlet of the main engine 1 and the liquid oxygen inlets of the four mobile engines 2 respectively. One end of the fuel delivery pipeline is connected to a fuel storage tank, and the other end of the fuel delivery pipeline is connected to the fuel inlet of the main engine 1 and the fuel inlets of the four mobile engines 2 respectively.

[0040] The liquid oxygen delivery pipeline includes a spherical six-way structure 6, which has one inlet and five outlets. The inlet of the spherical six-way structure 6 is connected to the liquid oxygen tank of the aircraft, and the five outlets of the spherical six-way structure 6 are respectively connected to the liquid oxygen inlets of the main engine 1 and the four cruise engines 2. The fuel delivery pipeline includes the main engine fuel delivery pipeline 4 and the cruiser fuel delivery pipeline 5. One end of the main engine fuel delivery pipeline 4 is connected to the fuel tank, and the other end is connected to the fuel inlet of the main engine 1. The cruiser fuel delivery pipeline 5 includes a spherical five-way structure 51, which includes one inlet and four outlets. The inlet of the spherical five-way structure 51 is connected to the fuel tank of the aircraft, and the four outlets are respectively connected to the fuel inlets of the four cruisers 2.

[0041] Example 5 The power configuration of the vertical takeoff and landing reusable aircraft includes a main engine 1, four cruisers 2, and a five-aircraft parallel frame 3. The main engine 1 is located at the center of the five-aircraft parallel frame 3, and the four cruisers 2 are evenly distributed around the main engine 1 on the five-aircraft parallel frame 3. The main engine 1 and the four cruisers 2 are also connected to a closed-loop control system.

[0042] The five-machine parallel large frame 3 includes an upper end face 31, a lower end face 32, and eight V-shaped support force transmission rods 33; the upper end face 31 is a regular octagonal frame with eight vertex joints; the lower end face 32 is a square frame with four vertices and four midpoints of the sides, with the midpoints of the sides located at the middle of each side; the upper end face 31 and the lower end face 32 are connected by the V-shaped support force transmission rods 33.

[0043] The V-shaped support force transmission rod 33 is formed by two connecting rods rigidly intersecting at a bend point. The two free ends of each V-shaped support force transmission rod 33 are rigidly connected to two adjacent vertices on the regular octagonal frame, and the bend point of each V-shaped support force transmission rod 33 is rigidly connected to the square frame. The bend points of multiple V-shaped support force transmission rods 33 are continuously arranged along the circumference of the square frame and are alternately connected to the vertices and midpoints of the sides of the square frame. Cross beams are fixedly connected to the midpoints of the four sides of the square frame. The main engine 1 includes a thrust chamber and a constant level seat structure. One end of the constant level seat structure is fixedly connected to the top of the thrust chamber by bolts, and the other end of the constant level seat structure is fixedly installed at the center of the bottom of the cross beam of the five-machine parallel large frame 3 by bolts. Each of the four mobile units 2 is equipped with a thrust chamber and a constant level seat structure. The thrust chamber of each mobile unit 2 is connected to the corresponding constant level seat structure by bolts. The other end of each constant level seat structure is fixedly connected to the bottom center of the four vertices of the square frame of the five-machine parallel large frame 3 by bolts.

[0044] A thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of the main engine 1, and a thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of each of the four vernier engines 2. The main engine 1 and each vernier engine 2 are independently equipped with a set of servo mechanisms. Each set of servo mechanisms includes a servo cylinder trunnion and a servo piston rod. That is, the main engine 1 corresponds to a set of servo mechanisms, and each vernier engine 2 corresponds to an independent set of servo mechanisms. Each servo mechanism does not interfere with each other and works independently.

[0045] The bottom of the cross beam is also fixed with a support. The servo mechanism of the main engine 1 is connected to the servo cylinder trunnion of the servo mechanism through a pin and hinged to the support at the bottom of the cross beam of the five-machine parallel large frame 3. The square frame is also fixed with four supports. The servo mechanism of the four mobile engines 2 is connected to the servo cylinder trunnion of the four mobile engines through a pin and hinged to the support at the bottom of the square frame of the five-machine parallel large frame 3. The servo mechanisms of the main engine 1 and each motor 2 are equipped with servo piston rods that are hinged to the thrust chamber swing support of the corresponding main engine 1 or motor 2 via pins; this enables the servo mechanism to be connected to the corresponding engine and the five-engine parallel frame 3, ensuring that each engine can be independently controlled through its own servo mechanism.

[0046] It also includes a liquid oxygen delivery pipeline and a fuel delivery pipeline. One end of the liquid oxygen delivery pipeline is connected to a liquid oxygen storage tank, and the other end of the liquid oxygen delivery pipeline is connected to the liquid oxygen inlet of the main engine 1 and the liquid oxygen inlet of the four mobile engines 2 respectively. One end of the fuel delivery pipeline is connected to a fuel storage tank, and the other end of the fuel delivery pipeline is connected to the fuel inlet of the main engine 1 and the fuel inlet of the four mobile engines 2 respectively.

[0047] The liquid oxygen delivery pipeline includes a spherical six-way structure 6, which has one inlet and five outlets. The inlet of the spherical six-way structure 6 is connected to the liquid oxygen tank of the aircraft, and the five outlets of the spherical six-way structure 6 are respectively connected to the liquid oxygen inlets of the main engine 1 and the four cruise engines 2. The fuel delivery pipeline includes the main engine fuel delivery pipeline 4 and the cruiser fuel delivery pipeline 5. One end of the main engine fuel delivery pipeline 4 is connected to the fuel tank, and the other end is connected to the fuel inlet of the main engine 1. The cruiser fuel delivery pipeline 5 includes a spherical five-way structure 51, which includes one inlet and four outlets. The inlet of the spherical five-way structure 51 is connected to the fuel tank of the aircraft, and the four outlets are respectively connected to the fuel inlets of the four cruisers 2.

[0048] The main engine 1 uses a gas generator circulation system, and the four mobile engines 2 are all powered by electric pumps.

[0049] Example 6 The power configuration of the vertical takeoff and landing reusable aircraft includes a main engine 1, four cruisers 2, and a five-aircraft parallel frame 3. The main engine 1 is located at the center of the five-aircraft parallel frame 3, and the four cruisers 2 are evenly distributed around the main engine 1 on the five-aircraft parallel frame 3. The main engine 1 and the four cruisers 2 are also connected to a closed-loop control system.

[0050] The five-machine parallel large frame 3 includes an upper end face 31, a lower end face 32, and eight V-shaped support force transmission rods 33; the upper end face 31 is a regular octagonal frame with eight vertex joints; the lower end face 32 is a square frame with four vertices and four midpoints of the sides, with the midpoints of the sides located at the middle of each side; the upper end face 31 and the lower end face 32 are connected by the V-shaped support force transmission rods 33.

[0051] The five-machine parallel large frame 3 adopts a five-machine parallel central symmetrical layout, with one main engine 1 arranged in the center and four mobile engines 2 evenly arranged in the circumference. The spatial truss members are rigidly connected through nodes. The symmetrical layout ensures that the thrust and vibration load of the main and mobile engines are evenly transmitted, avoiding local stress concentration.

[0052] The V-shaped support force transmission rod 33 is formed by two connecting rods rigidly intersecting at a bend point. The two free ends of each V-shaped support force transmission rod 33 are rigidly connected to two adjacent vertices on the regular octagonal frame, and the bend point of each V-shaped support force transmission rod 33 is rigidly connected to the square frame. The bend points of multiple V-shaped support force transmission rods 33 are continuously arranged along the circumference of the square frame and are alternately connected to the vertices and midpoints of the sides of the square frame. Cross beams are fixedly connected to the midpoints of the four sides of the square frame. The main engine 1 includes a thrust chamber and a constant level seat structure. One end of the constant level seat structure is fixedly connected to the top of the thrust chamber by bolts, and the other end of the constant level seat structure is fixedly installed at the center of the bottom of the cross beam of the five-machine parallel large frame 3 by bolts. Each of the four mobile units 2 is equipped with a thrust chamber and a constant level seat structure. The thrust chamber of each mobile unit 2 is connected to the corresponding constant level seat structure by bolts. The other end of each constant level seat structure is fixedly connected to the bottom center of the four vertices of the square frame of the five-machine parallel large frame 3 by bolts.

[0053] A thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of the main engine 1, and a thrust chamber swing support is fixedly installed on the outer wall of the thrust chamber of each of the four vernier engines 2. The main engine 1 and each vernier engine 2 are independently equipped with a set of servo mechanisms. Each set of servo mechanisms includes a servo cylinder trunnion and a servo piston rod. That is, the main engine 1 corresponds to a set of servo mechanisms, and each vernier engine 2 corresponds to an independent set of servo mechanisms. Each servo mechanism does not interfere with each other and works independently.

[0054] The bottom of the cross beam is also fixed with a support. The servo mechanism of the main engine 1 is connected to the servo cylinder trunnion of the servo mechanism through a pin and hinged to the support at the bottom of the cross beam of the five-machine parallel large frame 3. The square frame is also fixed with four supports. The servo mechanism of the four mobile engines 2 is connected to the servo cylinder trunnion of the four mobile engines through a pin and hinged to the support at the bottom of the square frame of the five-machine parallel large frame 3. The servo mechanisms of the main engine 1 and each motor 2 are equipped with servo piston rods that are hinged to the thrust chamber swing support of the corresponding main engine 1 or motor 2 via pins; this enables the servo mechanism to be connected to the corresponding engine and the five-engine parallel frame 3, ensuring that each engine can be independently controlled through its own servo mechanism.

[0055] The main engine 1 is located at the center of the power system and has a bidirectional swing function. It achieves vector control of thrust by installing two servo mechanisms. The main engine 1 adopts a gas generator circulation mode and has a ground rated thrust of 57.4 tons. By adjusting the flow rate of the gas generator, the operating conditions can be adjusted within the range of 70% to 100% thrust. It also has the ability to start ignition twice.

[0056] The electric pump supply method adopted by the 2nd turbine has a simple supply system. The rated thrust of a single 2nd turbine on the ground is 3.77 tons. By synchronously changing the speed of the electric pump servo motor in the liquid oxygen and fuel supply system, the thrust of the 2nd turbine can be continuously adjusted over a wide range. The thrust adjustment range exceeds 2:1. Each 2nd turbine has the ability to start and ignite three times.

[0057] It also includes a liquid oxygen delivery pipeline and a fuel delivery pipeline. One end of the liquid oxygen delivery pipeline is connected to a liquid oxygen storage tank, and the other end of the liquid oxygen delivery pipeline is connected to the liquid oxygen inlet of the main engine 1 and the liquid oxygen inlet of the four mobile engines 2 respectively. One end of the fuel delivery pipeline is connected to a fuel storage tank, and the other end of the fuel delivery pipeline is connected to the fuel inlet of the main engine 1 and the fuel inlet of the four mobile engines 2 respectively.

[0058] The liquid oxygen delivery pipeline includes a spherical six-way structure 6, which has one inlet and five outlets. The inlet of the spherical six-way structure 6 is connected to the liquid oxygen tank of the aircraft, and the five outlets of the spherical six-way structure 6 are respectively connected to the liquid oxygen inlets of the main engine 1 and the four cruise engines 2. The fuel delivery pipeline includes the main engine fuel delivery pipeline 4 and the cruiser fuel delivery pipeline 5. One end of the main engine fuel delivery pipeline 4 is connected to the fuel tank, and the other end is connected to the fuel inlet of the main engine 1. The cruiser fuel delivery pipeline 5 includes a spherical five-way structure 51, which includes one inlet and four outlets. The inlet of the spherical five-way structure 51 is connected to the fuel tank of the aircraft, and the four outlets are respectively connected to the fuel inlets of the four cruisers 2.

[0059] The liquid oxygen delivery system and the fuel delivery system adopt an integrated structure-pipeline layout. The pipeline is integrated along the truss members. The core propellant distribution node is a spherical multi-pass structure. Its smooth transition flow channel can achieve uniform distribution of fluids in multiple branches, which reduces flow resistance and eddies and ensures uniform and stable flow field at the inlet of each engine. The overall configuration is formed by the collaborative design of the five-engine parallel large frame 3 and the delivery system.

[0060] The main engine 1 uses a gas generator circulation system, and the four mobile engines 2 are all powered by electric pumps.

[0061] The closed-loop control system includes a mission profile planning and main control module, a multivariable coupled closed-loop control law module, a thrust distribution and servo control module, a modal decision and switching control unit, a modal class module, a multi-source sensing module, and a redundancy fault-tolerant and fault reconstruction control unit. The multi-source sensing module, modal decision and switching control unit, modal class module, redundancy fault-tolerant and fault reconstruction control unit, mission profile planning and main control module, multivariable coupled closed-loop control law module, and thrust distribution and servo control module are interconnected.

[0062] The mission profile planning and main control module pre-stores core thresholds for start-up, shutdown, secondary ignition of the main and wandering engines, secondary shutdown of the main and wandering engines, as well as altitude, speed, overload, dynamic pressure, attitude, servo position, thrust, and working condition switching for each stage. The multivariable coupled closed-loop control law module is used to automatically switch the coupled control strategy according to the core control objectives of different modes, and automatically switch the control outer loop at different stages. The attitude outer loop is used during takeoff and landing, the overload outer loop is used during climb, and the speed outer loop is used during deceleration, so as to adapt to the full mission profile conditions. The thrust distribution and servo control module is used to execute the control commands output by the multivariable coupled closed-loop control law module, control the ignition and shutdown of the main engine 1 and the four vernier engines 2, and linearly control the thrust of the main engine 1 and the four vernier engines 2; at the same time, it controls the servo mechanism of the main engine 1 and the four vernier engines 2 to actuate the nozzle vector deflection, so that the aircraft maintains the required attitude. The mode decision and switching control unit is used to determine the current mission phase and switch to the corresponding control mode. At the mode switching node, the mode decision and switching control unit determines the mode of the aircraft through dual thresholds of speed and altitude, and switches to a smooth transition algorithm to accurately switch modes. The modal modules include six modes: vertical takeoff, climb load limit, inertial taxiing, reentry trim, active deceleration, and soft landing. Based on the control of the modal decision and switching control unit, different modal control multivariable coupled closed-loop control law modules are used accordingly. The multi-source sensing module is used to collect real-time data on aircraft altitude, speed, overload, attitude, engine thrust, and servo position. The redundancy-tolerant and fault reconstruction control unit is used to detect the fault status of the main engine and four vernier engines. When a fault occurs in the main engine or vernier engine, it immediately performs thrust reconstruction and redistribution of thrust between the main engine and vernier engines, and compensates for the deviation by symmetrically adjusting the non-faulty engines.

[0063] Example 7 The aircraft adopts the vertical takeoff and landing reusable aircraft power configuration of Example 6. The flight mission profile of the aircraft is shown in the figure below. Figure 7As shown, after the main engine 1 and the four propellers 2 shut down once, the rocket body separates from the manned spacecraft after reaching the set thrust, attitude, altitude and dynamic pressure thresholds. The rocket body continues to control the flight according to the closed-loop control system of the present invention, while the manned spacecraft is controlled by its own control system. The flight altitude, speed, overload, thrust adjustment process, and total thrust change curve of the aircraft in this embodiment are shown in the figure. Figures 8-12 When the aircraft takes off, the main engine 1 and the four vernier engines 2 all ignite, generating a total thrust of 73.9 tons. The total mass of the aircraft is 57.5 tons, sufficient for vertical takeoff. The servo mechanisms of the main engine 1 and vernier engines 2 maintain a vertical upward flight attitude. As propellant is consumed, the aircraft's speed and altitude continuously increase. To control flight overload, the total thrust is gradually reduced to approximately 80% every 100 seconds, maintaining this operating condition. When the aircraft reaches an altitude of 50 km, all engines shut down. The aircraft continues to fly upward under inertia until its speed drops to zero, reaching a maximum altitude of 120 km.

[0064] Then, under the influence of Earth's gravity, the spacecraft entered the return and descent phase. The altitude gradually decreased, and the descent speed continuously increased. When the spacecraft reached an altitude of 30km and a speed of 1300m / s, the main engine 1 ignited for the second time to decelerate the spacecraft, operating at 70% capacity for 40 seconds. When the spacecraft's altitude decreased to approximately 3km and its speed to 130m / s, the four vernier engines 2 ignited, and the main engine 1 subsequently shut down. By synchronously adjusting the thrust of the four vernier engines 2, the total thrust was gradually reduced to less than 20%, and the spacecraft's speed was controlled to be below 2m / s before landing, achieving a soft landing.

[0065] Working process and principle: After the closed-loop control system is powered on and initialized, the multi-source sensor module collects real-time data on the aircraft's altitude, speed, overload, attitude, engine thrust, and servo position, and transmits this data synchronously to the modal decision-making and switching control unit and the redundancy fault tolerance and fault reconstruction control unit. The mission profile planning and main control module pre-stores core threshold parameters for each stage of start-up, shutdown, secondary ignition, secondary shutdown, altitude, speed, overload, dynamic pressure, attitude, servo position, thrust, and operating condition switching. It controls the modal decision-making and switching control unit to determine the current mission stage and switch the corresponding control mode. At the switching node, the built-in modal matching, speed and altitude dual threshold triggering, and smooth transition algorithm are used to complete the precise switching, achieving a smooth transition of total thrust during the switching process without attitude abrupt changes or overload exceeding limits. The closed-loop control system follows... Figure 6 The flowchart logic is used to automatically execute closed-loop control in six stages. Phase 1: Vertical Takeoff Mode (Ground → Takeoff, Mode 1) The modal decision and switching control unit triggers the takeoff command and switches to the vertical takeoff mode; the multivariable coupled closed-loop control law module uses attitude and overload as the core feedback variables; the thrust distribution and servo control module outputs the ignition command for the entire aircraft, the main engine and four vernier engines ignite synchronously, the thrust of the main engine and vernier engines is adjusted in a closed loop, and the servo mechanism is driven to actuate the nozzle vector deflection, so that the aircraft maintains a vertical upward attitude, without off-center loading or attitude changes.

[0066] Phase 2: Climbing and Load Limiting Mode (Takeoff → 50km, Mode 2) The modal decision and switching control unit switches to the climb load limiting mode. The multivariable coupled closed-loop control law module prioritizes constraining flight overload. The thrust distribution and servo control module gradually reduces the total thrust based on overload feedback. The main engine bears the main thrust, while the cruiser only makes minor attitude adjustments under low thrust. The vector nozzle deflects slightly to maintain a stable climb trajectory. When the aircraft reaches the 50km altitude threshold, the thrust distribution and servo control module outputs a shutdown command, and the main engine and cruiser shut down simultaneously.

[0067] Phase 3: Inertial gliding mode (50km→120km maximum point, mode 3) The modal decision and switching control unit switches to the inertial gliding mode, and the multivariable coupled closed-loop control law module maintains a stable closed loop without power, with both the main engine and the cruiser operating without power. The thrust distribution and servo control module controls the nozzle vector to deflect slightly, working in conjunction with aerodynamic trim to maintain the aircraft's attitude stability. The aircraft ascends by inertia until its speed drops to 0, reaching a maximum altitude of 120km. The multi-source sensor module continuously monitors altitude and attitude data to prepare for the reentry phase.

[0068] Phase 4: Reentry trim mode (120km→30km, mode 4) The mode decision and switching control unit switches to the reentry trim mode. The aircraft descends under the influence of gravity. The multivariable coupled closed-loop control law module prioritizes the reentry attitude trim closed loop. The thrust distribution and servo control module adjusts the aircraft's angle of attack and attitude in real time to avoid attitude loss of control during reentry. When the altitude drops to the 30km threshold, the mode decision and switching control unit prepares to switch to mode 5, and the main engine secondary ignition preparation command is given.

[0069] Phase 5: Active deceleration mode (30km→3km, mode 5) The modal decision and switching control unit switches to active deceleration mode, and the thrust distribution and servo control module outputs commands to enable the main engine to ignite independently, while the vernier remains powered off. The multivariable coupled closed-loop control law module uses descent speed and overload as the core feedback variables to precisely adjust the main engine thrust to achieve deceleration. The closed-loop control ensures that the descent speed and overload do not exceed the limits, guaranteeing the structural safety of the aircraft. When the altitude drops to the 3km threshold, the vernier ignition command is triggered to initiate the linear transfer of thrust between the main and vernier engines.

[0070] Phase 6: Soft landing mode (3km → ground, mode 6) The modal decision and switching control unit switches to the soft landing mode. The thrust distribution and servo control module outputs commands to synchronize the ignition of the four rovers. The main engine thrust decreases linearly, and the rovers thrust increases linearly. After a smooth transition, the main engine shuts down. The thrust distribution and servo control module takes full control of the four rovers and synchronously adjusts their thrust in a closed loop. Combining multi-variable feedback of altitude, speed, and attitude, it precisely controls the descent speed. The aircraft touches down smoothly and outputs a shutdown command, completing the entire mission.

[0071] The multivariable coupled closed-loop control law module can automatically switch coupled control strategies for different modal core control objectives and automatically switch control outer loops at different stages (takeoff / landing: attitude outer loop; climb: overload outer loop; deceleration: speed outer loop), adapting to full-profile operating conditions; The redundancy fault-tolerant and fault reconstruction control unit can immediately perform thrust reconstruction if the main engine or the main engine fails. The main engine thrust distribution and servo control unit symmetrically adjust the remaining engines to compensate for deviations, ensuring mission reliability.

[0072] The closed-loop control method for the power configuration of a vertical takeoff and landing reusable aircraft is carried out according to the following steps: Step 1: The multi-source sensor module collects various data from the aircraft in real time and transmits them synchronously to the mode decision and switching control unit and the redundancy fault tolerance and fault reconstruction control unit. Step 2: The modal decision and switching control unit determines the current task stage and switches the corresponding control mode based on the data collected by the multi-source sensor module, the task profile planning, and the data pre-stored in the main control module. Step 3: The multivariable coupled closed-loop control law module automatically switches the coupled control strategy according to the core control objective of the corresponding control mode to complete the flight mission.

Claims

1. A power configuration for a vertical takeoff and landing reusable aircraft, characterized in that, It includes a main engine (1), four mobile units (2) and a five-unit parallel frame (3). The main engine (1) is located at the center of the five-unit parallel frame (3). The four mobile units (2) are evenly arranged around the main engine (1) on the five-unit parallel frame (3). The main engine (1) and the four mobile units (2) are all connected to a closed-loop control system.

2. The power configuration of the vertical takeoff and landing reusable aircraft according to claim 1, characterized in that, The five-machine parallel large frame (3) includes an upper end face (31), a lower end face (32) and eight V-shaped support force transmission rods (33); the upper end face (31) is a regular octagonal frame with eight vertex joints; the lower end face (32) is a square frame with four vertices and four midpoints of the sides, and the midpoints of the sides are located in the middle of each side; the upper end face (31) and the lower end face (32) are connected by V-shaped support force transmission rods (33).

3. The power configuration of the vertical takeoff and landing reusable aircraft according to claim 2, characterized in that, The V-shaped support force transmission rod (33) is formed by two connecting rods rigidly intersecting at a bend point. The two free ends of each V-shaped support force transmission rod (33) are rigidly connected to two adjacent vertices on the regular octagonal frame, and the bend point of each V-shaped support force transmission rod (33) is rigidly connected to the square frame. The bend points of multiple V-shaped support force transmission rods (33) are continuously arranged along the circumference of the square frame and are alternately connected to the vertices and midpoints of the sides of the square frame. The four midpoints of the sides of the square frame are fixedly connected to cross beams. The main engine (1) includes a thrust chamber and a constant level seat structure. One end of the constant level seat structure is fixedly connected to the top of the thrust chamber by bolts, and the other end of the constant level seat structure is fixedly installed at the center of the bottom of the cross beam of the five-machine parallel large frame (3) by bolts. Each of the four motors (2) is equipped with a set of thrust chambers and constant level seat structures. The thrust chambers of each motor (2) are connected to the corresponding constant level seat structures by bolts. The other end of each constant level seat structure is fixedly connected to the bottom center of the four vertices of the square frame of the five-machine parallel large frame (3) by bolts.

4. The power configuration of the vertical takeoff and landing reusable aircraft according to claim 3, characterized in that, The main engine (1) has a thrust chamber swing support fixed on the outer wall of the thrust chamber, and the four motors (2) each have a thrust chamber swing support fixed on the outer wall of the thrust chamber; the main engine (1) and each motor (2) are each independently equipped with a set of servo mechanisms, and each set of servo mechanisms includes a servo cylinder trunnion and a servo piston rod. The bottom of the cross beam is also fixedly connected to a support. The servo mechanism of the main engine (1) is hinged to the support at the bottom of the cross beam of the five-machine parallel frame (3) through a pin. The square frame is also fixedly connected to four supports. The servo mechanism of the four mobile engines (2) is hinged to the support at the bottom of the square frame of the five-machine parallel frame (3) through a pin. The servo piston rods of the main engine (1) and each motor (2) are all hinged to the thrust chamber swing support of the corresponding main engine (1) or motor (2) via pins.

5. The power configuration of the vertical takeoff and landing reusable aircraft according to claim 4, characterized in that, It also includes a liquid oxygen delivery pipeline and a fuel delivery pipeline. One end of the liquid oxygen delivery pipeline is connected to a liquid oxygen storage tank, and the other end of the liquid oxygen delivery pipeline is connected to the liquid oxygen inlet of the main engine (1) and the liquid oxygen inlets of the four motors (2) respectively. One end of the fuel delivery pipeline is connected to a fuel storage tank, and the other end of the fuel delivery pipeline is connected to the fuel inlet of the main engine (1) and the fuel inlets of the four motors (2) respectively.

6. The power configuration of the vertical takeoff and landing reusable aircraft according to claim 5, characterized in that, The liquid oxygen delivery pipeline includes a spherical six-way structure (6), which includes one inlet and five outlets. The inlet of the spherical six-way structure (6) is connected to the liquid oxygen tank of the aircraft, and the five outlets of the spherical six-way structure (6) are respectively connected to the liquid oxygen inlets of the main engine (1) and the four cruisers (2). The fuel delivery pipeline includes a main engine fuel delivery pipeline (4) and a cruiser fuel delivery pipeline (5). One end of the main engine fuel delivery pipeline (4) is connected to the fuel tank, and the other end is connected to the fuel inlet of the main engine (1). The cruiser fuel delivery pipeline (5) includes a spherical five-way structure (51). The spherical five-way structure (51) includes one inlet and four outlets. The inlet of the spherical five-way structure (51) is connected to the fuel tank of the aircraft, and the four outlets are respectively connected to the fuel inlets of the four cruisers (2).

7. The power configuration of a vertical takeoff and landing reusable aircraft according to claim 6, characterized in that, The main engine (1) adopts a gas generator circulation method, and the four motors (2) all adopt an electric pump supply method.

8. The power configuration of a vertical takeoff and landing reusable aircraft according to claim 7, characterized in that, The closed-loop control system includes a mission profile planning and main control module, a multivariable coupled closed-loop control law module, a thrust distribution and servo control module, a modal decision and switching control unit, a modal class module, a multi-source sensing module, and a redundancy fault tolerance and fault reconstruction control unit. The multi-source sensing module, modal decision and switching control unit, modal class module, redundancy fault tolerance and fault reconstruction control unit, mission profile planning and main control module, multivariable coupled closed-loop control law module, and thrust distribution and servo control module are interconnected in pairs.

9. The power configuration of a vertical takeoff and landing reusable aircraft according to claim 8, characterized in that, The task profile planning and main control module pre-stores core thresholds for start-up, shutdown, main engine secondary ignition, main engine secondary shutdown, and each stage's altitude, speed, overload, dynamic pressure, attitude, servo position, thrust, and operating condition switching. The mission profile planning and main control module pre-stores core thresholds for start-up, shutdown, secondary ignition of the main and wandering engines, secondary shutdown of the main and wandering engines, as well as altitude, speed, overload, dynamic pressure, attitude, servo position, thrust, and working condition switching for each stage. The multivariable coupled closed-loop control law module is used to automatically switch the coupled control strategy according to the core control objectives of different modes, and automatically switch the control outer loop at different stages. The attitude outer loop is used during takeoff and landing, the overload outer loop is used during climb, and the speed outer loop is used during deceleration, so as to adapt to the full mission profile conditions. The thrust distribution and servo control module is used to execute the control commands output by the multivariable coupled closed-loop control law module, control the ignition and shutdown of the main engine (1) and the four vernier engines (2), and linearly control the thrust of the main engine (1) and the four vernier engines (2); at the same time, it controls the servo mechanism of the main engine (1) and the four vernier engines (2) to actuate the nozzle vector deflection so that the aircraft maintains the required attitude. The mode decision and switching control unit is used to determine the current mission stage and switch to the corresponding control mode; at the mode switching node, the mode decision and switching control unit determines the mode of the aircraft through dual thresholds of speed and altitude, and switches to a smooth transition algorithm to accurately switch modes; The modal modules include six modes: vertical takeoff, climb load limiting, inertial taxiing, reentry trim, active deceleration, and soft landing. Based on the control of the modal decision and switching control unit, different modal control multivariable coupled closed-loop control law modules are used accordingly. The multi-source sensing module is used to collect real-time data on aircraft altitude, speed, overload, attitude, engine thrust, and servo position. The redundancy fault tolerance and fault reconstruction control unit is used to detect the fault status of the main engine and four vernier engines. When the main engine or vernier engine fails, it immediately performs thrust reconstruction and redistribution of thrust of the main engine and vernier engines, and compensates for the deviation by symmetrically adjusting the non-faulty engines.

10. A closed-loop control method for a vertical takeoff and landing (VTOL) reusable aircraft power configuration, applied to the VTOL reusable aircraft power configuration described in claim 8 or 9, characterized in that, Includes the following steps: Step 1: The multi-source sensor module collects various data from the aircraft in real time and transmits them synchronously to the mode decision and switching control unit and the redundancy fault tolerance and fault reconstruction control unit. Step 2: The modal decision and switching control unit determines the current task stage and switches the corresponding control mode based on the data collected by the multi-source sensor module, the task profile planning, and the data pre-stored in the main control module. Step 3: The multivariable coupled closed-loop control law module automatically switches the coupled control strategy according to the core control objective of the corresponding control mode to complete the flight mission.

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