High-precision spatial GNC full-physical simulation test platform and test method

Abstract

The invention belongs to the technical field of spacecraft ground simulation testing, and discloses a high-precision space GNC full-physical simulation test platform which is composed of a three-dimensional motion execution system, a distributed real-time control system, a capture interaction simulation system, a safety protection system and a three-dimensional motion simulation and path planning system. By integrating a three-dimensional track type large-range motion execution system and a double-grating ruler closed-loop detection structure, the simulation motion range is remarkably expanded, the technical bottleneck that an existing platform is limited by a single axis, a two-dimensional sliding rail and limited motion amplitude is broken through, high-precision cooperation of a motion control system and a track system is achieved through the platform, and high-precision cooperation of the motion control system and the track system is achieved. The space high-dynamic motion simulation of a large-size and high-inertia complex target can be met, autonomous tracking of a target flight path, flexible capture of a flying claw and small multi-degree-of-freedom control verification are supported through integrated design of a capture interactive simulation system, and complex tasks such as space rendezvous and docking, target capture and micro-force control can be effectively simulated.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of spacecraft ground simulation test, and particularly relates to a high-precision space GNC full-physical simulation test platform and an experimental method. BACKGROUND

[0002] The existing space GNC simulation verification technology mainly depends on a single-dimensional motion platform or a distributed simulation architecture, is limited by the device structure and the control ability, and generally has problems of narrow motion range, dynamic response lag and insufficient system synchronization accuracy; in particular, in the face of space rendezvous docking, high-speed motion capture and other scenes of complex targets of large size and high inertia, the existing simulation platform is difficult to realize continuous, large-range and high-dynamic physical closed-loop verification in three-dimensional space, which seriously restricts the authenticity and effectiveness of the ground simulation test.

[0003] The single-axis air floating table, two-dimensional slide rail system and six-degree-of-freedom platform widely used at present can complete local motion simulation, but the control logic of each system is dispersed, the motion amplitude is limited, and the motion simulation demand of large stroke, high synchronization and high accuracy in the real space environment cannot be met, resulting in a large deviation between the experimental results and the actual on-orbit operation.

[0004] In addition, the existing simulation platform lacks integrated design of motion and target capture interaction, and cannot effectively support complex path dynamic capture, micro-force control and high-precision interaction verification. SUMMARY

[0005] The application aims to provide a high-precision space GNC full-physical simulation test platform and an experimental method to solve the problems in the background technology.

[0006] In order to achieve the above purpose, the application provides the following technical scheme: a high-precision space GNC full-physical simulation test platform, which is composed of a three-dimensional motion execution system, a distributed real-time control system, a capture interaction simulation system, a safety protection system and a three-dimensional motion simulation and path planning system.

[0007] The three-dimensional motion execution system is based on a steel rail track, uses P43 steel rails in X and Y directions, hydraulic buffer limiters, gear racks and screw drives, double grating scale closed-loop detection and gravity unloading mechanisms to provide basic motion support for the simulation platform.

[0008] The distributed real-time control system contains a ground control console, double-redundant servo controllers (FPGA+DSP architecture, cycle <1ms), EtherCAT bus nodes (synchronization error <500us) and a motion monitoring unit to drive three-axis synchronous motion.

[0009] Capture interaction simulation system: There are claw capture devices (flexible fingers, stroke ≥ 3 meters), multi-degree-of-freedom control devices, situation awareness and multi-dimensional measurement simulators for space target capture and micro-force control verification;

[0010] Safety protection system: Equipped with double redundant emergency stop circuit, dynamic interference detection module, hydraulic buffer limiter (stroke ≥ 50 mm) and anti-overturning structure, real-time monitoring of motion, safety protection;

[0011] Three-dimensional motion simulation and path planning system: Including three-dimensional modeling (supporting.STP format), path planning, interference detection module, and motion backtracking optimization function, realizing modeling, planning and data backtracking;

[0012] Preferably, the three-dimensional motion execution system comprises:

[0013] (1) Track structure and driving mechanism: Based on steel rail track structure, X and Y directions use rigid heavy P43 steel rails, end hydraulic buffer limiter ensures operation safety, in the gear rack and lead screw driving mechanism, servo motor is connected through rigid coupling, planetary reducer drives the track, its motion follows the track driving kinematics model combining speed, displacement and time, and the lead screw is responsible for vertical motion, providing stable basic motion support for the system;

[0014] The track driving kinematics model expression formula is:

[0015]

[0016] In the formula, S: motion displacement (unit: m), v: initial speed (unit: m / s), a: motion acceleration (unit: m / s2), t: motion time (unit: s), real-time guidance for track motion control;

[0017] It can ensure the accuracy of displacement calculation during three-axis motion, support position prediction during high-speed motion, and improve the real-time response capability of overall motion control; three-dimensional track motion belongs to rigid structure driving, and the basic kinematics formula can quickly calculate the motion displacement, which is helpful for planning the motion trajectory in advance and conducting safety protection, especially suitable for long-stroke and large-inertia motion platforms;

[0018] (2) Detection and unloading mechanism: The double-gauge ruler closed-loop detection device collects X, Y and Z axis position and speed signals in real time through double channels, and feeds back to the motion control system for accurate control; the gravity unloading steel wire rope mechanism uses a pulley block to reduce the vertical load according to the relationship between force and motion in the track driving kinematics model, and works cooperatively in two sections, effectively reducing the vertical motion load and improving the system operation efficiency and stability.

[0019] Preferably, the distributed real-time control system comprises:

[0020] (1) Control core architecture: The ground console as the hub integrates high-performance industrial computers, fiber optic reflective memory card interfaces, and real-time operating systems. The dual-redundant servo motion controller uses an FPGA+DSP architecture, with a motion control cycle of less than 1 ms. Its control follows the associated logic of feedback and instructions in the servo motor speed closed-loop control model, providing precise driving cores for three-axis synchronous motion.

[0021] The servo motor speed closed-loop control model expression formula is:

[0022]

[0023] where v out (t): controller output speed command (unit: m / s), v ref (t): reference speed (unit: m / s), v meas (t): actual measured speed (unit: m / s), K p : speed loop proportional coefficient, K i : speed loop integral coefficient, ensuring motion following accuracy.

[0024] The servo motor speed real-time closed-loop control of the three-dimensional motion platform effectively reduces motion deviation and improves path following accuracy. The speed loop proportional-integral control is a common control basis for servo systems, which can achieve low-latency, high-precision real-time motion control combined with feedback speed, suitable for multi-axis synchronous motion requirements of distributed motion platforms.

[0025] (2) Distributed synchronization and monitoring: EtherCAT bus nodes achieve distributed synchronization control, with node clock synchronization error less than 500μs, ensuring collaborative accuracy. The motion monitoring unit collects motor parameters through the servo driver, combined with the parameter association logic in the speed closed-loop control model, to provide data support for real-time adjustment of the system, ensuring efficient synchronization of three-axis motion.

[0026] Preferably, the capture interaction simulation system comprises:

[0027] (1) Capture execution device: three rope synchronous belt drive flexible claws, surface nitrile rubber buffer layer, telescopic stroke over 3 meters, its capture follows the associated logic of force and contact state in the flying claw capture mechanics model, small multi-degree-of-freedom control device, six-degree-of-freedom servo motor driven mechanical arm, joint torque sensor, clamping force and stroke range are clear, and precise control can be executed;

[0028] According to the target mass and relative acceleration, the flying claw clamping force is adjusted in real time to ensure stable clamping and no damage to the target during dynamic capture.

[0029] The flying claw needs to calculate the clamping force in real time when capturing a moving target to prevent the target from slipping due to insufficient clamping and prevent the target from being damaged due to excessive clamping. Coupling of the clamping force and the motion state is an important safety control parameter of a dynamic capture system.

[0030] (2) Perception and measurement system: The situation awareness simulator integrates a 64-line laser radar and a vision unit to capture the position and attitude of a flying target in real time. A six-axis force sensor of the multi-dimensional measurement simulator is used to collect contact data at a frequency of not less than 1000 Hz, thereby providing data support for capture and control verification.

[0031] Preferably, the safety protection system comprises:

[0032] (1) Safety control core mechanism: A dual-redundant emergency stop circuit independently controls a dual-loop servo power supply to ensure reliable shutdown in an emergency. A dynamic interference detection module calculates the safety distance of a path from surrounding equipment based on the correlation between distance and motion parameters in a real-time minimum safety distance model, monitors the motion state in real time, and dynamically adjusts the path.

[0033] The expression formula of the real-time minimum safety distance model is:

[0034]

[0035] In the formula, d min : current minimum safety distance (unit: m), (x1, y1, z1): current center point coordinates of the motion platform (unit: m), (x2, y2, z2): coordinates of the nearest point of the surrounding equipment (unit: m);

[0036] The minimum safety distance between the motion platform and the surrounding equipment is monitored in real time to trigger obstacle avoidance or stop in a timely manner to prevent mechanical collision during the motion process.

[0037] Three-dimensional real-time safety distance detection is the key to the protection of the motion platform. The bounding box distance formula can quickly complete safety judgment during high-speed motion, and is particularly suitable for obstacle avoidance control in complex paths and dynamic environments.

[0038] (2) Protection structure guarantee: The hydraulic buffer limiting structure has a buffer stroke of not less than 50 mm, which can effectively absorb impact energy. The anti-overturning guide structure includes a double-wheel side guide and a side wheel limiting frame. Combined with the spatial constraint logic of the real-time minimum safety distance model, the system provides multiple safety guarantees to ensure stable and safe motion.

[0039] Preferably, the three-dimensional motion simulation and path planning system comprises:

[0040] (1) Modeling and path planning module: the three-dimensional modeling module supports importing three-dimensional models in multiple formats to provide basic model support for the system, the path planning module adopts a priority path search algorithm and a motion constraint inverse solution method, which calculates the real-time motion path in accordance with the multi-factor weighting logic in the path planning priority cost function, and meets the system motion planning requirements;

[0041] The principle expression formula of the path planning priority cost function is:

[0042] C total =w d ·d p +w v ·v p +w a ·a p

[0043] In the formula, C total : current path cost, d p : path length (unit: m), v p : path speed variation (unit: m / s), a p : path acceleration variation (unit: m / s2), w d , w v , w a : distance, speed and acceleration weight coefficients respectively;

[0044] The path length, speed variation and acceleration variation are dynamically considered during path planning, the optimal path is calculated through weighted priority, and the path smoothness and motion efficiency are improved;

[0045] The multi-target path planning meets the engineering requirements of a complex motion control system, can adapt to different motion conditions through weight adjustment, and is particularly suitable for a high dynamic capture and simulation platform;

[0046] (2) Interference detection and data backtracking module: the interference detection module calculates a safety distance through a bounding box real-time collision detection algorithm to ensure motion safety, the motion backtracking and parameter optimization module can record historical paths and adjust parameters, combines the optimization idea of the path planning priority cost function, realizes motion data backtracking and parameter optimization, and improves system performance.

[0047] The application also provides the following technical scheme: a high-precision space GNC full-physical simulation experiment method based on the above system, and the specific steps of the method are as follows:

[0048] S1: platform initialization, start the three-dimensional motion execution system, the motion control system completes the X, Y, Z three-axis zero point calibration in turn through the double grating ruler, real-time acquisition of servo motor current and position signal, three-dimensional motion simulation system imports flight path data, time synchronization is completed through the optical fiber reflection memory card and the control system;

[0049] S2: path loading and motion execution, the ground console loads the target flight path, the motion control system generates servo motor motion instructions based on the simulation path, drives three-axis synchronous motion through EtherCAT bus, captures interactive simulation system real-time follow motion path to execute claw stretching and mechanical arm trajectory action, safety protection system real-time monitoring motion state and interference distance, motion control system dynamically adjusts servo input through model predictive control algorithm, realizes dynamic load synchronous compensation;

[0050] S3: target capture and interactive simulation, real-time tracking of flight target based on laser radar point cloud data and visual recognition image through the situation awareness simulator, claw capture device captures target autonomously according to motion control system feedback trajectory, small multi-degree-of-freedom control device executes real-time micro-force control, three-dimensional motion simulation system calculates path safety distance and performs motion data backtracking in real time, if the minimum safety distance is detected to be insufficient, the safety protection system issues path adjustment or stop instructions through the motion control system.

[0051] Preferably, in the platform initialization stage of S1, first start the three-dimensional motion execution system, the motion control system completes X, Y, Z three-axis zero point calibration in turn through the double grating ruler closed loop detection device, ensures the accuracy of the motion reference, at the same time, the system real-time acquisition of servo motor current, position these key signals, realize dynamic monitoring, three-dimensional motion simulation system imports flight path data synchronously, through the optical fiber reflection memory card interface of the ground console, and the motion control system achieves time synchronization, lays a unified time sequence foundation for subsequent motion modeling, path planning and real-time interference detection, guarantees the consistency and accuracy of the whole platform collaborative operation.

[0052] Preferably, the specific steps of path loading and motion execution in S2 are as follows:

[0053] S21, path loading and driving: the ground console loads the target flight path, the motion control system generates servo motor motion instructions based on the simulation path, drives three-axis synchronous motion through EtherCAT bus, captures interactive simulation system real-time follow, executes claw stretching and mechanical arm trajectory action, its control is integrated into the dynamic adjustment logic of model predictive control motion correction model;

[0054] The expression formula of the model predictive control motion correction model is:

[0055]

[0056] Where u(t): current control input (servo command), y(t+k|t): predicted future motion trajectory, r(t+k): expected reference trajectory, N p : prediction step, Q, R: state weight matrix and control weight matrix;

[0057] During motion execution, the servo command is dynamically adjusted based on the future motion trajectory prediction to compensate for path deviation in advance and achieve high-precision tracking;

[0058] S22, Motion Control and Protection: The safety protection system monitors the motion status and interference distance in real time. The motion control system adopts a model predictive control algorithm to dynamically adjust the servo input according to the correlation between the error and the adjustment amount in the motion correction model, realize dynamic load synchronous compensation, ensure motion accuracy and safety, and ensure stable and reliable execution process.

[0059] Preferably, the target capture and interactive simulation in S3 refers to real-time tracking of flying targets by a situational awareness simulator with the help of lidar point cloud data and visual recognition images, the flying claw capture device autonomously completes target capture based on the trajectory feedback from the motion control system, the small multi-degree-of-freedom manipulation device synchronously performs micro-force manipulation, and the three-dimensional motion simulation system calculates the path safety distance in real time and backtracks the motion data. Once it is detected that the minimum safety distance is insufficient, the safety protection system immediately issues a path adjustment or stop command through the motion control system to ensure that the entire capture and manipulation process is safe and controllable;

[0060] The expression formula of point cloud data is:

[0061]

[0062] Where, T: target current posture transformation matrix, p i : Point cloud coordinates measured by the sensor, q i : The reference point coordinates of the target model, n: the number of point cloud data.

[0063] The beneficial effects of the present invention are as follows:

[0064] 1. The present invention significantly expands the range of simulated motion by integrating a three-dimensional track-type large-range motion execution system with a dual-grating scale closed-loop detection structure. This breaks through the technical bottleneck of existing platforms that are limited to single-axis, two-dimensional slide rails and limited motion amplitude. The platform achieves high-precision coordination between the motion control system and the track system, which can meet the spatial high-dynamic motion simulation of large-scale, high-inertia and complex targets. The overall motion simulation capability is significantly better than the existing technology.

[0065] 2, The application supports autonomous tracking of target flight path, flexible capture of flying claws and small multi-degree-of-freedom control verification through integrated design of the capture interaction simulation system, can effectively simulate complex tasks such as space rendezvous and docking, target capture and micro-force control, and the platform supports target identification based on point cloud data and vision fusion, path dynamic adjustment and multi-dimensional force control interaction, solves the problem that the existing simulation platform cannot complete high dynamic target capture and real-time interaction verification, and significantly improves the ground verification capability and simulation authenticity of space complex tasks.

[0066] 3, The simulation platform provided by the application adopts full-physical closed-loop design, bidirectional coupling of distributed real-time control system and motion simulation system, and double-redundancy safety protection system, realizes high synchronization, strong real-time closed-loop control of motion path planning, target capture, interaction control and safety protection, control cycle is less than 1ms, the system has high safety redundancy design, real-time monitoring of motion state and safety distance, and has the ability of emergency obstacle avoidance and path correction under sudden working conditions, provides a stable, safe and reliable simulation experiment environment for high-risk space tasks. BRIEF DESCRIPTION OF DRAWINGS

[0067] Fig. 1 The application is a high-precision space GNC full-physical simulation test platform flowchart.

[0068] Fig. 2 The application is a high-precision space GNC full-physical simulation test method flowchart. DETAILED DESCRIPTION

[0069] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, not all. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the application.

[0070] As shown in the drawings, Figs. 1-2 The application provides a high-precision space GNC full-physical simulation test platform, which is composed of a three-dimensional motion execution system, a distributed real-time control system, a capture interaction simulation system, a safety protection system and a three-dimensional motion simulation and path planning system.

[0071] Example of a three-dimensional motion execution system: The three-dimensional motion execution system adopts an industrial-grade track structure. The X and Y direction tracks use P43 heavy-duty steel rails, each track is 20 meters and 15 meters long, respectively. Hydraulic buffer limiters with a stroke greater than 50mm are set at the track ends. The servo motor uses Panasonic model MSMF042L1 U2M, which is matched with a planetary reducer to drive the gear rack movement through a rigid coupling. The transmission side clearance is less than 0.02mm; Z-axis vertical movement is supported by a ball screw and a dual-guide slider. The screw drive motor has a power of 1.5kW. Position detection uses a Heidenhain brand dual-channel absolute grating scale with a resolution of 0.01mm. The motion position signal is collected in real time and fed back to the control system. The gravity unloading mechanism uses a Ø3mm wire rope pulley set, and the vertical motion load reduction is achieved through the pre-tensioned hammer design;

[0072] Distributed real-time control system implementation: The ground control console uses an ADLINK industrial control computer equipped with the RTX real-time operating system and a fiber-optic reflective memory card for high-speed data exchange. The motion controller uses the Beckhoff C6670 dual-redundant servo motion controller with a control cycle of less than 1ms. The control nodes form a global synchronization network via the EtherCAT bus, with a node synchronization error of less than 500μs. The motion monitoring unit uses sensors integrated into the servo drive to collect motor current, voltage, speed, and acceleration information in real time, and transmits the monitoring data back to the motion controller for motion state feedback and closed-loop adjustment.

[0073] In this interactive capture simulation system, the flying claw capture device uses flexible claws driven by three synchronous belts. The claws are covered with 2mm thick nitrile rubber cushions, and the claws have a designed retractable travel of 3.5 meters. The flying claws are connected to the motion platform via a slider structure. The situational awareness simulator uses a RoboSense 64-line LiDAR and a Basler industrial camera. The LiDAR has a refresh rate of 20Hz and collects target path information in real time. The multi-dimensional measurement simulator uses an ATI six-axis force sensor with a force measurement range of ±600N, a torque measurement range of ±15Nm, and a data sampling frequency of 1000Hz.

[0074] Safety protection system implementation: The safety protection system uses the Beckhoff safety control module to build a dual-redundant emergency stop circuit. The servo power supply independently controls the dual-circuit emergency power-off channels. The dynamic interference detection module communicates with the motion controller in real time through the embedded bounding box real-time collision detection software. The safety distance warning threshold is set at 100mm. If it falls below the threshold, a path adjustment or emergency stop command is immediately issued. The hydraulic buffer limit structure uses a FESTO hydraulic buffer with a buffer stroke of 50mm. The buffer load can withstand impacts at the platform's maximum operating speed. The anti-overturning guide structure uses dual-wheel side guides and slide rail limiters to prevent lateral instability of the motion platform.

[0075] Embodiment of three-dimensional motion simulation and path planning system: the three-dimensional motion simulation system is based on MATLAB / Simulink to build a simulation module, supporting importing CATIA and UGNX models in.STP and.OBJ formats; the path planning module is designed based on priority path search algorithm and motion constraint inverse solution method, and the path planning software supports real-time calculation of path speed and acceleration constraint conditions; the interference detection module integrates a fast bounding box collision detection algorithm, the collision detection refresh frequency is less than 20ms, the motion data backtracking module supports full-process path recording and parameter playback, supports exporting path optimization adjustment results, and feeds back to the motion control system in real time;

[0076] Among them, the three-dimensional motion execution system comprises:

[0077] (1) Track structure and driving mechanism: based on steel rail track structure, rigid heavy P43 steel rails are used in X and Y directions, end hydraulic buffer limiters are used to ensure operation safety, in the gear rack and lead screw driving mechanism, the servo motor is connected through a rigid coupling, the planetary reducer drives the track, its movement follows the track driving kinematics model combining speed, displacement and time, and the lead screw is responsible for vertical movement, providing stable basic motion support for the system;

[0078] The track driving kinematics model expression formula is:

[0079]

[0080] In the formula, S: motion displacement (unit: m), v: initial speed (unit: m / s), a: motion acceleration (unit: m / s2), t: motion time (unit: s), real-time guidance track motion control;

[0081] (2) Detection and unloading mechanism: the double-gauge ruler closed-loop detection device collects X, Y and Z axis position and speed signals in real time through double channels, and feeds back to the motion control system for accurate control; the gravity unloading steel wire rope mechanism uses a pulley block to reduce the vertical load according to the relationship between force and motion in the track driving kinematics model, and works in two sections in cooperation, effectively reducing the vertical motion load and improving the system operation efficiency and stability.

[0082] Among them, the distributed real-time control system comprises:

[0083] (1) Control core architecture: the ground console as the hub integrates a high-performance industrial computer, a fiber optic reflective memory card interface and a real-time operating system, a dual-redundant servo motion controller adopts an FPGA+DSP architecture, the motion control cycle is less than 1ms, and its control follows the correlation logic of feedback and instruction in the servo motor speed closed-loop control model, providing accurate driving core for three-axis synchronous motion;

[0084] The servo motor speed closed-loop control model expression formula is:

[0085]

[0086] In the formula, v out (t): controller output speed command (unit: m / s), v ref (t): reference speed (unit: m / s), v meas (t): actual measured speed (unit: m / s), K p : speed loop proportional coefficient, K i : speed loop integral coefficient, to ensure motion following accuracy;

[0087] (2) Distributed synchronization and monitoring: EtherCAT bus node realizes distributed synchronization control, and the node clock synchronization error is less than 500 μs, which guarantees the cooperation accuracy. The motion monitoring unit collects motor parameters through the servo driver, and combines the parameter correlation logic in the speed closed-loop control model to provide data support for real-time adjustment of the system, and ensures efficient synchronization of three-axis motion.

[0088] The capture interaction simulation system comprises:

[0089] (1) Capture execution device: three rope synchronous belt drive flexible claws, surface nitrile rubber buffer layer, telescopic stroke more than 3 meters, which captures the associated logic of force and contact state in the flying claw capture mechanics model, small multi-degree-of-freedom control device, six-degree-of-freedom servo motor driven mechanical arm, joint torque sensor, clamping force and stroke range are clear, and can accurately execute control;

[0090] (2) Perception and measurement system: situation awareness simulator integrates 64-line laser radar and vision unit, which can capture the position and attitude of the flying target in real time. The six-axis force sensor of the multi-dimensional measurement simulator collects contact data, and the update frequency is not less than 1000 Hz, which provides data support for capture and control verification.

[0091] The safety protection system comprises

[0092] (1) Safety control core mechanism: double-redundant emergency stop circuit independently controls double-loop servo power supply, ensuring reliable shutdown in emergency situations. The dynamic interference detection module is based on the bounding box algorithm, and calculates the safety distance of the path and the surrounding equipment according to the association of distance and motion parameters in the real-time minimum safety distance model, and dynamically adjusts the path according to the real-time monitoring of the motion state.

[0093] The real-time minimum safety distance model expression formula is:

[0094]

[0095] In the formula, dmin : current minimum safety distance (unit: m), (x1, y1, z1): current center point coordinates of the motion platform (unit: m), (x2, y2, z2): coordinates of the nearest point of the peripheral device (unit: m);

[0096] (2) Protection structure guarantee: The hydraulic buffer limiting structure has a buffer stroke of not less than 50 mm, which can effectively absorb impact energy. The anti-overturning guide structure includes double-wheel side guide and side wheel limiting frame, and in combination with the spatial constraint logic of the real-time minimum safety distance model, multiple safety guarantees are provided for the system, ensuring stable and safe movement;

[0097] The three-dimensional motion simulation and path planning system comprises:

[0098] (1) Modeling and path planning module: The three-dimensional modeling module supports importing three-dimensional models in multiple formats to provide basic model support for the system. The path planning module adopts a priority path search algorithm and a motion constraint inverse solution method. The calculation follows the multi-factor weighting logic in the path planning priority cost function, and can accurately calculate the real-time motion path to meet the system motion planning requirements;

[0099] The principle expression formula of the path planning priority cost function is:

[0100] C total =w d ·d p +w v ·v p +w a ·a p

[0101] In the formula, C total : current path cost, d p : path length (unit: m), v p : path speed change (unit: m / s), a p : path acceleration change (unit: m / s2), w d ,w v ,w a : distance, speed, and acceleration weight coefficients, respectively;

[0102] (2) Interference detection and data backtracking module: The interference detection module calculates the safety distance through the bounding box real-time collision detection algorithm to ensure the safety of the movement. The movement backtracking and parameter optimization module can record the historical path and adjust the parameters, and in combination with the optimization idea of the path planning priority cost function, the movement data backtracking and parameter optimization are realized to improve the system performance.

[0103] The embodiment of the application also provides a high-precision space GNC full-physical simulation experiment method based on the high-precision space GNC full-physical simulation test platform, and the specific steps of the method are as follows:

[0104] S1: platform initialization, starting a three-dimensional motion execution system, the motion control system completing X, Y and Z three-axis zero point calibration in sequence through double grating rulers, collecting servo motor current and position signals in real time, the three-dimensional motion simulation system importing flight path data, and completing time synchronization through a fiber reflection memory card and the control system;

[0105] S2: path loading and motion execution, the ground console loading a target flight path, the motion control system generating servo motor motion instructions based on a simulation path, driving three-axis synchronous motion through an EtherCAT bus, capturing an interactive simulation system to follow a motion path in real time to execute claw extension and mechanical arm trajectory action, a safety protection system monitoring motion state and interference distance in real time, and the motion control system dynamically adjusting servo input through a model predictive control algorithm to realize dynamic load synchronous compensation;

[0106] S3: target capture and interactive simulation, a situation awareness simulator tracking a flight target based on laser radar point cloud data and visual recognition images in real time, a claw capture device autonomously capturing a target according to motion control system feedback trajectory, a small multi-degree-of-freedom control device executing micro-force control in real time, a three-dimensional motion simulation system calculating path safety distance and performing motion data backtracking in real time, and if the minimum safety distance is detected to be insufficient, the safety protection system issuing path adjustment or stop instructions through the motion control system.

[0107] In the platform initialization stage in S1, firstly, a three-dimensional motion execution system is started, the motion control system completes X, Y and Z three-axis zero point calibration in sequence through a double grating ruler closed loop detection device, ensures accurate motion reference, meanwhile, the system collects current, position and other key signals of the servo motor in real time, realizes dynamic monitoring, the three-dimensional motion simulation system imports flight path data in synchronization, through a fiber reflection memory card interface of the ground console, reaches time synchronization with the motion control system, lays a unified time sequence foundation for subsequent motion modeling, path planning and real-time interference detection, guarantees consistency and accuracy of collaborative operation of the whole platform.

[0108] In S2, the specific steps of path loading and motion execution are as follows:

[0109] S21, path loading and driving: the ground console loads a target flight path, the motion control system generates servo motor motion instructions according to a simulation path, drives three-axis synchronous motion through an EtherCAT bus, captures an interactive simulation system to follow in real time, executes claw extension and mechanical arm trajectory action, and the control is integrated into the dynamic adjustment logic of the model predictive control motion correction model;

[0110] The expression formula of the motion correction model is:

[0111]

[0112] In the formula, u(t): current control input (servo command), y(t+k|t): predicted future motion trajectory, r(t+k): expected reference trajectory, N p : prediction step, Q, R: state weight matrix and control weight matrix;

[0113] S22, motion control and protection: the safety protection system monitors the motion state and intervention distance in real time, the motion control system adopts the model predictive control algorithm, dynamically adjusts the servo input according to the correlation between the error and the adjustment amount in the motion correction model, realizes dynamic load synchronous compensation, guarantees the motion precision and safety, and ensures the stability and reliability of the execution process.

[0114] Among them, the target capture and interaction simulation in S3 refers to tracking the flight target in real time through the situation awareness simulator with the help of laser radar point cloud data and visual recognition image, the target capture device autonomously completes the target capture according to the trajectory feedback of the motion control system, the small multi-degree-of-freedom control device synchronously executes the micro-force control, the three-dimensional motion simulation system calculates the path safety distance in real time and traces back the motion data, once the minimum safety distance is detected to be insufficient, the safety protection system immediately issues a path adjustment or stop instruction through the motion control system, ensuring the safety and controllability of the entire capture and control process.

[0115] The expression formula of the point cloud data is:

[0116]

[0117] In the formula, T: current attitude transformation matrix of the target, p i : point cloud coordinates measured by the sensor, q i : reference point coordinates of the target model, n: number of point cloud data.

[0118] It should be noted that in this paper, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment.

[0119] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely exemplary of the principles and application of the present application. Numerous modifications and adaptions can be effected without departing from the spirit and scope of the present application, which is not limited to the exact construction and arrangement described. It is intended, therefore, to cover all modifications and adaptions that fall within the scope of the claims and their equivalents.

Claims

1. A high-precision spatial GNC full-physics simulation test platform, characterized by: The platform consists of a 3D motion execution system, a distributed real-time control system, a capture interaction simulation system, a safety protection system, and a 3D motion simulation and path planning system; Three-dimensional motion execution system: Based on the steel rail track, P43 steel rails are used in the X and Y directions with hydraulic buffer limiters. It is equipped with a gear rack and screw drive mechanism, a double grating scale closed-loop detection device and a gravity unloading mechanism to provide basic motion support for the simulation test platform; Distributed real-time control system: including ground control console, dual redundant servo controllers, EtherCAT bus nodes and motion monitoring units, driving three-axis synchronous motion; Capture interactive simulation system: equipped with a flying claw capture device, a multi-degree-of-freedom manipulation device, a situational awareness and multi-dimensional measurement simulator, used for space target capture and micro-force manipulation verification; Safety protection system: equipped with dual redundant emergency stop circuits, dynamic interference detection module, hydraulic buffer limit and anti-overturning structure, real-time movement monitoring to ensure safety; 3D motion simulation and path planning system: Contains 3D modeling, path planning, interference detection modules and motion backtracking optimization functions to achieve modeling, planning and data backtracking.

2. A high-precision spatial GNC full-physics simulation test platform according to claim 1, characterized in that: The three-dimensional motion execution system includes: (1) Track structure and drive mechanism: Based on the steel rail track structure, rigid heavy-duty P43 steel rails are used in the X and Y directions. The hydraulic buffer limiter at the end ensures safe operation. In the gear rack and screw drive mechanism, the servo motor is connected to the planetary reducer through a rigid coupling to drive the track. Its movement follows the track drive kinematic model that combines the relationship between speed, displacement and time. The screw is responsible for vertical movement. The kinematic model of the track drive is expressed as follows: Where, S: motion displacement, v: initial velocity, a: motion acceleration, t: motion time; (2) Detection and unloading mechanism: The double-grating scale closed-loop detection device collects the X, Y, and Z axis position and speed signals in real time through dual channels and feeds them back to the motion control system. The gravity unloading wire rope mechanism uses a pulley set to reduce the vertical load according to the relationship between force and motion in the track drive kinematic model. It is divided into two sections and works together.

3. The high-precision spatial GNC full-physics simulation test platform according to claim 1 is characterized by: The distributed real-time control system comprises: (1) Control core architecture: The ground control console integrates a high-performance industrial computer, a fiber-optic reflex memory card interface, and a real-time operating system. The dual-redundant servo motion controller adopts an FPGA+DSP architecture, with a motion control cycle of less than 1ms. Its control follows the correlation logic between feedback and instructions in the servo motor speed closed-loop control model, providing a precise drive core for three-axis synchronous motion. The expression formula of the servo motor speed closed-loop control model is: Where, v out (t): Controller output speed command, v ref (t): reference speed, v meas (t): Actual measured speed, K p : Speed ​​loop proportional coefficient, K i : Speed ​​loop integral coefficient; (2) Distributed synchronization and monitoring: EtherCAT bus nodes implement distributed synchronization control, and the node clock synchronization error is less than 500μs, ensuring the coordination accuracy. The motion monitoring unit collects multiple motor parameters through the servo drive and combines them with the parameter association logic in the speed closed-loop control model.

4. The high-precision spatial GNC full-physics simulation test platform according to claim 1 is characterized by: The capture interaction simulation system comprises: (1) Capture execution device: The flexible claw is driven by three rope synchronous belts, and the surface is provided with a nitrile rubber buffer layer. The telescopic stroke exceeds 3 meters. Its capture follows the correlation logic between force and contact state in the flying claw capture mechanics model. It is a small multi-degree-of-freedom control device, a six-degree-of-freedom servo motor drives the robotic arm, and is equipped with a joint torque sensor. The clamping force and stroke range are clear, and the control can be performed accurately. (2) Perception and measurement system: The situational awareness simulator integrates a 64-line laser radar and a vision unit to capture the position and attitude of the flying target in real time. The six-axis force sensor of the multi-dimensional measurement simulator collects contact data with an update frequency of no less than 1000 Hz.

5. The high-precision spatial GNC full-physics simulation test platform according to claim 1 is characterized by: The safety protection system includes: (1) Core safety control mechanism: Dual redundant emergency stop circuits independently control dual-circuit servo power supplies to ensure reliable shutdown in emergency situations. The dynamic interference detection module is based on the bounding box algorithm. According to the relationship between distance and motion parameters in the real-time minimum safety distance model, it calculates the safe distance between the path and surrounding equipment, monitors the motion status in real time, and dynamically adjusts the path. The real-time minimum safety distance model expression formula is: Where, d min : Current minimum safety distance, (x1, y1, z1): Current center coordinates of the motion platform, (x2, y2, z2): The nearest coordinates of the peripheral equipment; (2) Protection structure guarantee: The hydraulic buffer limit structure has a buffer stroke of no less than 50 mm, and the anti-overturning guide structure includes double-wheel side guides and side wheel limit frames, combined with the spatial constraint logic of the real-time minimum safety distance model.

6. The high-precision spatial GNC full-physics simulation test platform according to claim 1 is characterized by: The three-dimensional motion simulation and path planning system includes: (1) 3D modeling and path planning module: The 3D modeling module supports the import of 3D models in various formats. The path planning module adopts a priority path search algorithm and a motion constraint inverse solution method. Its calculation follows the multi-factor trade-off logic in the path planning priority cost function and can accurately calculate the real-time motion path to meet the system motion planning requirements. The principle expression formula of path planning priority cost function is: C total =w d ·d p +w v ·v p +w a ·a p Where C total : Current path cost, d p : Path length, v p : Path speed change, a p : Path acceleration change, w d ,w v ,w a : are the weight coefficients of distance, speed and acceleration respectively; (2) Interference detection and data backtracking module: The interference detection module calculates the safe distance through the bounding box algorithm and the real-time collision detection algorithm to ensure the safety of movement. The movement backtracking and parameter optimization module can record the historical path and adjust the parameters. Combined with the optimization idea of ​​the path planning priority cost function, it realizes movement data backtracking and parameter optimization.

7. A high-precision spatial GNC full-physics simulation experimental method, characterized by: The high-precision spatial GNC full-physics simulation experimental method is based on the system described in claims 1-6, and the specific steps of the method are as follows: S1: Platform initialization, start the 3D motion execution system, the motion control system completes the X, Y, and Z axis zero point calibration in sequence through the dual grating ruler, collects the servo motor current and position signals in real time, the 3D motion simulation system imports the flight path data, and completes time synchronization with the control system through the optical fiber reflection memory card; S2: Path loading and motion execution: The ground control console loads the target flight path. The motion control system generates servo motor motion instructions based on the simulation path, drives three-axis synchronous motion via the EtherCAT bus, and captures the interactive simulation system to follow the motion path in real time to execute the claw extension and retraction and robot arm trajectory movements. The safety protection system monitors the motion status and interference distance in real time. The motion control system dynamically adjusts the servo input through the model predictive control algorithm to achieve dynamic load synchronous compensation. S3: Target capture and interactive simulation: The situational awareness simulator tracks the flying target in real time based on the lidar point cloud data and visual recognition images. The flying claw capture device autonomously captures the target according to the feedback trajectory of the motion control system. The small multi-degree-of-freedom manipulation device performs micro-force manipulation in real time. The three-dimensional motion simulation system calculates the path safety distance in real time and performs motion data backtracking. If it is detected that the minimum safety distance is insufficient, the safety protection system will issue a path adjustment or stop command through the motion control system.

8. A high-precision spatial GNC full-physics simulation experimental method according to claim 7, characterized in that: During the platform initialization phase in S1, the three-dimensional motion execution system is first started. The motion control system uses a dual-grating scale closed-loop detection device to sequentially complete the zero point calibration of the X, Y, and Z axes to ensure the accuracy of the motion reference. At the same time, the system collects the current and position key signals of the servo motor in real time to achieve dynamic monitoring. The three-dimensional motion simulation system synchronously imports flight path data and achieves time synchronization with the motion control system through the optical fiber reflection memory card interface of the ground control console.

9. A high-precision spatial GNC full-physics simulation experimental method according to claim 7, characterized in that: The specific steps of path loading and motion execution in S2 are as follows: S21, Path Loading and Driving: The ground control console loads the target flight path. The motion control system generates servo motor motion instructions based on the simulated path, drives the three-axis synchronous motion via the EtherCAT bus, and captures the interactive simulation system in real time to execute the claw extension and retraction and robot arm trajectory movements. Its control is integrated into the dynamic adjustment logic of the model predictive control motion correction model. The expression formula of the model predictive control motion correction model is: Where u(t): current control input (servo command), y(t+k|t): predicted future motion trajectory r(t+k): expected reference trajectory, N p : prediction step, Q, R: state weight matrix and control weight matrix; S22, Motion Control and Protection: The safety protection system monitors the motion status and interference distance in real time. The motion control system adopts a model predictive control algorithm to dynamically adjust the servo input according to the correlation between the error and the adjustment amount in the motion correction model, realize dynamic load synchronous compensation, and ensure motion accuracy and safety.

10. The high-precision spatial GNC full-physics simulation experimental method according to claim 7, characterized in that: The target capture and interactive simulation in S3 refers to the real-time tracking of flying targets by using the situational awareness simulator with the help of lidar point cloud data and visual recognition images. The flying claw capture device autonomously completes target capture based on the trajectory feedback from the motion control system. The small multi-degree-of-freedom manipulation device synchronously performs micro-force manipulation. The three-dimensional motion simulation system calculates the path safety distance in real time and traces back the motion data. Once the minimum safety distance is detected to be insufficient, the safety protection system immediately issues a path adjustment or stop command through the motion control system to ensure that the entire capture and manipulation process is safe and controllable. The expression formula of point cloud data is: Where, T: target current posture transformation matrix, p i : Point cloud coordinates measured by the sensor, q i : The reference point coordinates of the target model, n: the number of point cloud data.

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