Space environment ground simulation system and method for space additive manufacturing

Abstract

The application discloses a space environment ground simulation system and method for space additive manufacturing, and belongs to the technical field of space navigation condition simulation. The system comprises a first cabin, a second cabin and a third cabin which are sequentially sleeved from inside to outside. The third cabin is a posture adjusting cabin, and is internally provided with a mass center adjusting mechanism, a gyroscope and an accelerometer, and is used for dynamically stabilizing the cabin body under microgravity. The second cabin contains a laser head and a monitoring device, and detects the additive manufacturing process in the first cabin through a protection lens. The first cabin is internally provided with a forming substrate, a multi-axis motion platform and a wire feeding mechanism, and realizes laser wire feeding printing under vacuum / atmosphere controllable and wide temperature range substrate temperature control. The use method comprises three steps of preparation, microgravity printing, recovery and data acquisition. The application integrates active microgravity simulation, vacuum / atmosphere control, extreme temperature control and laser additive manufacturing for the first time, cooperates with a purification gas path and a cabin design, and solves the problems of process mismatch, low fidelity and single function of the prior art.

Description

Technical Field

[0001] This invention belongs to the technical field of simulation devices for spaceflight conditions, and particularly relates to a ground simulation system and method for space environment for space additive manufacturing. Background Technology

[0002] With the rapid advancement of aerospace technology and the emergence of missions such as deep space exploration, long-term on-orbit operation of space stations, and the construction of future extraterrestrial bases, there is an urgent need for on-orbit manufacturing and repair capabilities. On-orbit manufacturing and repair capabilities are considered key technologies for achieving autonomous reconfiguration of spacecraft structures and rapid replacement of core components. However, relying on platforms such as space stations, space shuttles, or sounding rockets to conduct experiments in real space environments faces a series of almost insurmountable challenges: firstly, the economic costs are extremely high; secondly, experimental opportunities are scarce, strictly limited by launch plans, module resources, and astronaut operation time. These bottlenecks severely hinder the research and development, process maturity, and engineering transformation of space manufacturing technologies. Therefore, developing a high-fidelity, low-cost, and repeatable space environment ground simulation system is an essential, fundamental, and strategic step for conducting early-stage principle verification, process parameter system optimization, and material-process compatibility research in space manufacturing technologies. It is the only way to move from the laboratory to space applications.

[0003] Existing ground-based simulation technologies for space environments have the following three main limitations, making it difficult to meet the needs for high-fidelity ground-based verification and research of metal additive manufacturing processes for on-orbit manufacturing in space:

[0004] First, the process types are mismatched, making it impossible to simulate continuous manufacturing processes. Microgravity rapid solidification methods, such as tube-feeding technology, electromagnetic levitation, and liquid quenching (e.g., CN113909461A, CN111230130A, CN107695359A), essentially aim to achieve deep undercooling and rapid solidification of metallic materials, belonging to discrete casting or solidification forming processes. This technical approach focuses on the microstructure and performance optimization at the materials science level. Its system design (e.g., levitation melting, static molds) does not include core additive manufacturing process units such as wire feeding, multi-axis linkage, and layer-by-layer deposition, and therefore cannot be used to study continuous, dynamic metal additive manufacturing processes in a space environment.

[0005] Secondly, the simulation principles are limited, resulting in insufficient environmental fidelity. Some ground-based simulation devices (such as CN120606169A) use principles such as aerodynamic negative pressure to locally balance gravity in a static environment. Although this can achieve "long-term, continuous" process simulation, the essence of the simulation is hydrodynamic effects, not the real physical microgravity environment. This method cannot accurately reproduce the core physical conditions in space when gravity levels are extremely low, natural convection is basically absent, and molten pool behavior is mainly dominated by surface tension and wettability. This leads to systematic deviations between the droplet transition, molten pool flow, and heat transfer phenomena observed on the ground and the real space environment, resulting in limited physical fidelity of the simulation.

[0006] Finally, the system's limited functionality makes it difficult to support complex process research. Existing technical solutions are often optimized for specific, single objectives. For example, integrated devices for space applications (such as CN119658137A) are typically designed to be compact and have limited functionality to meet launch constraints. Their process windows and environmental controls (such as temperature control range) are relatively fixed, resulting in insufficient flexibility and versatility for multi-parameter, wide-range process exploration on the ground.

[0007] Therefore, there is currently a lack of a comprehensive process research platform in a ground-based laboratory capable of conducting long-term, continuous research on the mainstream space manufacturing process of "laser-metal wire," which simultaneously integrates precise microgravity simulation, high-vacuum environment, and wide-temperature-range thermal control. This prevents in-depth exploration of the core mechanisms such as molten pool flow, defect formation, and microstructure evolution under the interaction of microgravity, vacuum, and extreme temperatures. Summary of the Invention

[0008] This invention addresses the problems existing in the prior art by proposing a ground simulation system and method for space environment in space additive manufacturing. The aim is to solve the problems of mismatched process types, insufficient environmental fidelity, and limited system functionality in the prior art.

[0009] To address the problems existing in the prior art, the present invention proposes the following technical solution:

[0010] A space printing environment simulation chamber for space additive manufacturing is characterized by comprising: a first chamber, a second chamber, and a third chamber arranged sequentially from the inside out; the first chamber, the second chamber, and the third chamber operate in concert within a main experimental chamber that can undergo controlled free fall or simulate microgravity motion via electromagnetic catapult, integrating a fully functional laser filament feeding additive manufacturing unit, a wide-temperature-range active temperature control substrate, a vacuum / atmosphere control system, and an online monitoring system, thereby completing the printing process within the microgravity time window and realizing comprehensive ground simulation and process research of the space manufacturing environment;

[0011] The third cabin is an attitude adjustment cabin, which is equipped with a center of mass adjustment mechanism, a gyroscope and an accelerometer. The center of mass adjustment mechanism is used to adjust the position of the cabin's center of mass to maintain attitude stability during free fall or electromagnetic catapult microgravity simulation motion. The gyroscope is used to sense changes in the cabin's attitude and the accelerometer is used to record the gravity level.

[0012] The second compartment is used to monitor the first compartment; the second compartment is fixedly installed inside the third compartment and is used to house the laser head and monitoring devices including high-speed photography and thermal imaging; the laser head transmits data to the forming environment of the first compartment through a protective lens on the wall of the first compartment; the high-speed photography and thermal imaging can respectively detect the additive manufacturing process in the first compartment through the protective lens;

[0013] The first compartment is used for 3D printing; the first compartment is fixedly installed inside the second compartment. First compartment The system includes a forming substrate, a multi-axis motion platform, and a wire feeding mechanism. The wire feeding mechanism is used to feed the wire onto the forming substrate at a set speed. The forming substrate serves as a support platform for part manufacturing and is mainly used to provide physical support and positioning. The forming substrate is mounted on the multi-axis motion platform. The multi-axis motion platform is used to realize the multi-dimensional motion (XYZW) of the forming substrate. All drive mechanisms of the multi-axis motion platform are optimized for microgravity environments.

[0014] Furthermore, the third compartment includes a cylindrical main body and a hemispherical top and bottom connected to the main body. A gyroscope is installed at the highest point of the hemispherical top and a gravity accelerometer is installed at the lowest point of the hemispherical bottom. A circular compartment mounting surface is formed at the connection between the bottom of the third compartment and the cylindrical main body. The second compartment and the first compartment are fixedly installed on the compartment mounting surface inside the first compartment.

[0015] Furthermore, the center of mass adjustment mechanism is located at the connection between the hemispherical top of the third cabin and the cylindrical main body. This connection has a circular center of mass adjustment surface, on which the center of mass adjustment mechanism is mounted. The center of mass adjustment mechanism includes a circular guide rail and multiple center of mass adjustment blocks mounted on the circular guide rail, with at least three blocks. Each center of mass adjustment block has the same mass and is evenly spaced along the circumference of the circular guide rail. A motor for driving the movement of the center of mass adjustment blocks is located at the center of the center of mass adjustment surface. When the cabin moves in a microgravity environment, a high-precision gyroscope senses the three-dimensional attitude changes of the cabin in real time and transmits the signals to the control system. After processing by the control system, if a deflection or rollover tendency is detected, the control system immediately drives the motor to move the corresponding center of mass adjustment block along the circular guide rail. By adjusting the mass distribution, the position of the cabin's center of mass is dynamically compensated, effectively counteracting the deflection torque and ensuring that the cabin maintains a stable falling attitude throughout the entire microgravity window.

[0016] Furthermore, the second chamber is used to monitor the first chamber. Specifically, the laser head is freely adjusted in three-dimensional space through a manually or automatically moving three-dimensional motion adjustment structure, which includes an a-axis, a b-axis, and a c-axis. In use, the a-axis is used to adjust the defocusing amount of the laser head, and the b-axis and c-axis are used to adjust the relative interaction position of the laser and the wire. In this case, by adjusting the position of the laser head through the a, b, and c axes, the laser is irradiated at point M on the substrate, which is the metal wire forming point.

[0017] Furthermore, the second chamber is a protective gas environment or an atmospheric environment. This protective gas environment or atmospheric environment allows the laser energy source, high-speed photography and thermal imaging monitoring devices, and solid-state batteries installed in the second chamber to be free from the technical barriers of vacuum environment applicability and to conduct experiments using conventional products. The laser energy source adopts fiber laser or semiconductor laser.

[0018] Furthermore, the first chamber is a high-vacuum / controllable atmosphere, extreme temperature simulation, and additive manufacturing chamber; the outer wall of the first chamber is made of acrylic or metal, and optical protective lenses are installed at the laser incident position, high-speed photography observation position, and thermal imager observation position; the protective lenses are used to transmit the laser from the second chamber and the corresponding optical signals used for observation; before the experiment, the chamber is evacuated to a high vacuum (e.g., 10⁻³~10⁻⁵ Pa) or filled with a protective gas of a predetermined composition (e.g., Ar, He); the wire feeding mechanism of the first chamber adopts a precision metal wire feeding device, and the wire material can be conventional titanium alloy, aluminum alloy, high-temperature alloy, or other crystalline metals with a diameter range of 0.2~2.0 mm.

[0019] Furthermore, the forming substrate of the first compartment is preferably a wide-temperature-range active temperature-controlled substrate; this wide-temperature-range active temperature-controlled substrate can precisely control the substrate temperature within a range of -40°C to +400°C or even wider, for simulating extreme temperatures in space or studying the influence of temperature gradients on forming; this wide-temperature-range active temperature-controlled substrate is prepared using a multi-temperature control mode splicing scheme and has a multi-layer structure; this wide-temperature-range active temperature-controlled substrate can be an integral design or a detachable design. When the wide-temperature-range active temperature-controlled substrate is a detachable design, a conventional forming substrate can be installed on a wide-temperature-range active temperature-controlled base.

[0020] Furthermore, the wide-temperature-range active temperature-controlled substrate of the first chamber comprises a three-layer structure: a surface layer, a middle layer, and a bottom layer. The surface layer is an additive manufacturing substrate, which serves as a support platform for part manufacturing, primarily providing physical support and positioning for the additive manufacturing process. The middle layer is a combination of a semiconductor cooling plate and a heating plate. The semiconductor cooling plate includes a cooling section on top and a heat dissipation section on the bottom. The heating plate contains heating rods and thermocouples. The heating plate and the semiconductor cooling plate are horizontally separated. By setting the structure of the middle layer, the temperature of the substrate can be controlled by a program to achieve additive manufacturing under different temperature modes. The bottom layer of the substrate is a heat insulation plate, which mainly isolates the direct heat transfer between the substrate and the multi-axis motion platform.

[0021] The space printing environment simulation chamber enables online monitoring, data synchronization and acquisition, and safe capture and recovery. Specifically, online monitoring includes high-speed cameras, infrared thermal imagers, and spectrometers to monitor the molten pool morphology, temperature field, and spatter behavior under microgravity in real time. Data synchronization and acquisition: All data, microgravity levels, and microgravity time during the additive manufacturing process are recorded synchronously. Safe capture and recovery: After the main chamber is recovered to the bottom, it is stably captured by pneumatic, hydraulic, or elastic buffer devices. After the experiment, the chamber can be opened to retrieve the printed sample.

[0022] A method for using a space printing simulation environment for space additive manufacturing, characterized by comprising the following steps:

[0023] Step 1, Preparation Stage: Load the metal wire into the wire feeding mechanism and install the substrate on the wide temperature range control seat; close the first chamber, evacuate or fill with protective gas, and preheat or precool the substrate to the target temperature.

[0024] Step 2, Microgravity Printing Stage: Before the cabin falls freely or undergoes microgravity simulation using electromagnetic catapults, the high-pressure inert gas cylinder and vacuum pump are removed. During the microgravity period, the laser, filament feeding mechanism, and motion mechanism are started simultaneously, and laser filament feeding additive manufacturing is performed on the substrate according to the preset path.

[0025] Step 3, Recovery and Data Acquisition Phase: After the main cabin is safely captured, it returns to normal gravity. The printed part is retrieved, and the process characteristics of laser wire feeding forming under microgravity, vacuum, and specific temperatures are analyzed using online monitoring data. In practical applications, this experimental equipment can be used to study the wetting and spreading behavior of metal wires on the substrate molten pool under microgravity; the transfer behavior of the molten metal wire end to the forming substrate under microgravity; and the wire drawing behavior at the end of the metal molten wire additive manufacturing process under microgravity. Advantages and effects of the present invention

[0026] 1. Functional Integration and Innovation: For the first time, it integrates four major functional modules: active microgravity simulation (i.e., free fall or microgravity simulation motion via electromagnetic catapult), high vacuum / multi-atmosphere environment control, extreme temperature control, and laser-filament additive manufacturing. This creates a complete printing system for terrestrial simulation of space environment in space additive manufacturing, rather than a single material preparation device or a printer designed for space applications.

[0027] 2. By setting up a center of mass adjustment mechanism in the third chamber, the mass of the chamber can be flexibly configured to adjust the center of mass position of the printing system, so that the chamber maintains a stable falling posture throughout the entire microgravity window and avoids tumbling that could lead to experimental failure.

[0028] 3. The wide-temperature-range active temperature control substrate is a prominent feature of this solution, which can realize dynamic substrate thermal control covering extreme temperatures (-40°C to +400°C). Existing technologies have not emphasized or realized active, programmed temperature control from cryogenic to high temperature, which is crucial for studying the material behavior under extreme temperature alternation in space.

[0029] 4. Outstanding scientific value: This system can provide unique experimental conditions for studying the suppression of molten pool convection, wetting and spreading behavior, defect formation mechanism, and the influence of vacuum and temperature coupling on the metallurgical behavior of materials under microgravity, directly serving the preliminary research of my country's space manufacturing technology. Attached Figure Description

[0030] Figure 1 : This is a schematic diagram of the printing system based on the first, second, and third compartments of the present invention;

[0031] Figure 2 : This is a schematic diagram of the printing system of the center of gravity adjustment mechanism installed in the third compartment of the present invention;

[0032] Figure 3 : This is a schematic diagram illustrating the internal structure of the second and third compartments of the printing system, which is the focus of this invention;

[0033] Figure 4 This is a schematic diagram showing the laser head starting to work.

[0034] Figure 5 : This is a schematic diagram of the structure of the wide-temperature-range temperature control base plate. Detailed Implementation Innovation of this invention

[0035] The innovation lies not in the "printing" itself, but in "how to simulate the space environment most realistically on the ground." Its core innovations are "functional integration" and "dynamic stabilization," which can be summarized into the following five breakthroughs:

[0036] For the first time, all four key elements are integrated into one system. Previous ground-based equipment either only simulated weightlessness but couldn't perform printing, or only controlled temperature while maintaining normal gravity. This system is the world's first to integrate these four elements—real microgravity (free fall), high vacuum / controlled atmosphere, wide temperature range control (-40℃ to +400℃), and laser filament feeding printing—into a single moving chamber. It's not a static chamber, but a mobile laboratory capable of completing the entire printing process in a dynamic, weightless environment.

[0037] A unique "anti-rollover" attitude stabilization mechanism. The greatest risk of freefall is cabin rollover (once rollover occurs, the molten pool splashes, and the experiment fails). Traditional methods rely on jet propulsion or flywheels, but the internal space of the cabin is extremely small. The unique feature of this system is: a movable counterweight is placed around the waist of the cabin, which, together with a gyroscope, senses the attitude in real time. Once a slight tilt is detected, the motor immediately drives the counterweight to move along a circular guide rail, dynamically compensating for the center of gravity like a "seesaw," ensuring that the cabin falls straight down like a "plumber." This purely mechanical center of gravity adjustment scheme is simpler, more reliable, and does not consume propellant than jet propulsion.

[0038] Wide-temperature-range active temperature-controlled substrate (simulating the alternating temperatures of space). The space environment is not only characterized by low temperatures but also by dramatic temperature fluctuations (sunlit surfaces reach hundreds of degrees Celsius, while shaded surfaces are below freezing). This system's substrate uses a combination of semiconductor cooling chips and heating rods, and can actively and dynamically switch between -40°C and +400°C via a programmed system. This is not simply about maintaining temperature; it simulates the "drastic temperature fluctuations within an orbital period" to study the impact of temperature gradients on printed microstructures—something that current technologies have not yet achieved.

[0039] The ingenious compartmentalized design reduces engineering complexity (bypassing the challenges of vacuum equipment). Precision components such as lasers, cameras, and batteries are not vacuum-resistant. The solution involves evacuating the printing chamber (first chamber) to a vacuum, while maintaining the equipment chamber (second chamber) at atmospheric pressure / protective gas, with optical protective lenses separating them. This allows laser and observation signals to penetrate, but expensive equipment doesn't require specially designed vacuum plates; commercially available off-the-shelf products can be used directly, significantly reducing costs and development risks. Design challenges and solutions of this invention

[0040] Challenges and Solutions in Microgravity Simulation and Attitude Stabilization

[0041] Design Challenges: The core of simulating microgravity on the ground is to subject the experimental chamber to free fall or ejection to counteract the effects of gravity. However, the fatal flaw of free fall is that any tiny initial disturbance in the chamber will be amplified in weightlessness, causing it to tumble. Once tumbling occurs, the molten pool splashes, the filament becomes entangled, and the experiment fails completely. Limitations of Existing Solutions: The conventional approach is to use jet propulsion or flywheels for active control, but the internal space is extremely small, jet propulsion introduces additional thrust that interferes with the purity of microgravity, and it also consumes propellant, failing to meet the stability requirements of the entire printing window.

[0042] This invention proposes a purely mechanical dynamic center of mass adjustment principle. A ring-shaped guide rail and multiple counterweights are installed at the waist of the cabin, working in conjunction with a high-precision gyroscope to sense attitude in real time. Once a deflection trend is detected, the control system drives a motor to move the counterweights to the corresponding positions. By changing the mass distribution, the system's center of mass shifts, generating a restoring torque, which, like a "plumber," keeps the cabin falling vertically. The essence of the principle is to achieve passive attitude stabilization using gravity gradients, without consuming working fluid or introducing additional forces, thus ensuring the purity of the microgravity environment.

[0043] Challenges and Solutions in Multiphysics Coupled Simulation

[0044] Design Challenges: The space environment is a complex interplay of multiple factors, including microgravity, high vacuum, and extreme temperature fluctuations, coupled in real time. However, traditional equipment can only simulate a single factor, disrupting the coupling effect between these factors and leading to systematic discrepancies between ground-based experimental data and real-world space conditions. Limitations of Existing Solutions: Devices such as tube-dropping and electromagnetic levitation only focus on material solidification under microgravity, neglecting the printing process; pneumatic negative pressure devices simulate hydrodynamic effects rather than actual microgravity, resulting in insufficient physical fidelity.

[0045] The present invention utilizes active microgravity (free fall / electromagnetic ejection), high vacuum / controllable atmosphere, and wide temperature range control. Integrated with the four functional modules of laser-fed additive manufacturing within the same motion cabin, printing is completed synchronously within the microgravity window. The underlying principle is the reconstruction and coupling of a multi-physics environment, reproducing on Earth the real-world scenario of multiple factors working together in space.

[0046] Challenges and Solutions for Temperature Control of Substrates in Extreme Temperatures

[0047] Design Challenges: The temperature difference between the sun-exposed and shaded sides in space orbit is extreme (-40℃ to +400℃), and there are periodic and violent alternations. Existing substrates can only be heated or cooled in one direction, and cannot simulate this dynamic thermal shock environment of "alternating hot and cold". Limitations of Existing Solutions: Conventional heating or cooling plates can only control temperature in one direction, with slow switching speeds, making it difficult to achieve large temperature jumps and cycles in a short period of time.

[0048] This invention employs a multi-layered structure where semiconductor cooling chips (Peltier effect active cooling) and heating rods (resistance heating) are arranged in a plane. Through program control, active, bidirectional, and programmed temperature switching is achieved, rapidly simulating dramatic temperature changes within the orbital period. The underlying principle is thermoelectric synergistic bidirectional temperature control, constructing a controllable temperature gradient field to study the influence of temperature alternation on molten pool solidification and microstructure.

[0049] Challenges and Solutions for Compatibility Between Vacuum Environment and Precision Equipment

[0050] Design challenges: High vacuum environment Under these conditions, precision electronic devices such as lasers, high frame rate cameras, and batteries cannot function properly, requiring expensive custom vacuum versions, and their reliability is difficult to guarantee.

[0051] Limitations of existing solutions: The conventional approach is to vacuum or seal all equipment together, which either leads to soaring costs or limited equipment selection and significantly reduced functionality.

[0052] This invention employs a compartmentalized pressure differential isolation design. The printing operation compartment (first compartment) is evacuated to a high vacuum, while the equipment compartment (second compartment) maintains a normal pressure / protective gas environment. Laser transmission and signal observation are conducted solely through optical protective lenses. All precision equipment is housed in the second compartment, utilizing readily available commercial off-the-shelf products. The fundamental principle is "functional compartmentalization, signal continuity"—vacuum and equipment isolation significantly reduce costs and development risks.

[0053] Challenges and Solutions for Protecting Optical Windows from Contamination

[0054] Design challenges: Laser printing generates a large amount of metal vapor and spatter, which, in a microgravity environment, has no gravity to settle, easily contaminating the top observation lens. This can block the "eyes" of the high-speed camera and thermal imager within milliseconds, resulting in the loss of data for the entire window period. Limitations of existing solutions: The conventional approach is to passively wait for the contaminants to settle naturally, but this process is extremely slow under microgravity, far exceeding the printing window duration.

[0055] The invention employs a vacuum extraction unit at the bottom of the first chamber. During printing, this unit actively extracts air, using pressure differential to drive the gas inside the chamber, carrying splashes, to flow directionally downwards instead of upwards. Simultaneously, the airflow forms an air curtain protective layer on the lens surface, providing double protection for a clear observation window. The fundamental principle is: forced convection directional extraction + air curtain isolation, actively purifying the chamber environment and ensuring high-quality data acquisition throughout the entire process.

[0056] Based on the above principles, this invention designs: 1. A space printing environment simulation cabin for space additive manufacturing, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, its features include: a first compartment, a second compartment, and a third compartment nested from the inside out; the first, second, and third compartments operate in concert, integrating a full-function laser filament additive manufacturing unit, a wide-temperature-range active temperature-controlled substrate, a vacuum / atmosphere control system, and an online monitoring system within a main experimental compartment that can be controlled to fall freely or undergo microgravity simulation motion via electromagnetic catapult, thereby completing the printing process within the microgravity time window and realizing comprehensive ground simulation and process research of the space manufacturing environment;

[0057] like Figure 2 As shown, the third cabin is an attitude adjustment cabin, which is equipped with a center of mass adjustment mechanism, a gyroscope and an accelerometer. The center of mass adjustment mechanism is used to adjust the position of the cabin's center of mass to maintain attitude stability during free fall or electromagnetic catapult microgravity simulation motion. The gyroscope is used to sense changes in the cabin's attitude and the accelerometer is used to record the gravity level.

[0058] like Figure 2 As shown, the second compartment is used to monitor the first compartment; the second compartment is fixedly installed inside the third compartment and is used to house the laser head and monitoring devices including high-speed photography and thermal imaging; the laser head transmits data to the forming environment of the first compartment through a protective lens on the wall of the first compartment; the high-speed photography and thermal imaging can respectively detect the additive manufacturing process in the first compartment through the protective lens;

[0059] like Figure 3 As shown, the first compartment is used for 3D printing; the first compartment is fixedly installed inside the second compartment. First Inside the cabin The system includes a forming substrate, a multi-axis motion platform, and a wire feeding mechanism. The wire feeding mechanism is used to feed the wire onto the forming substrate at a set speed. The forming substrate serves as a support platform for part manufacturing and is mainly used to provide physical support and positioning. The forming substrate is mounted on the multi-axis motion platform. The multi-axis motion platform is used to realize the multi-dimensional motion (XYZW) of the forming substrate. All drive mechanisms of the multi-axis motion platform are optimized for microgravity environments.

[0060] like Figure 1 , Figure 2 , Figure 3 As shown, the third compartment includes a cylindrical main body and a hemispherical top and bottom connected to the main body. A gyroscope is installed at the highest point of the hemispherical top and a gravity accelerometer is installed at the lowest point of the hemispherical bottom. A circular compartment mounting surface is formed at the connection between the bottom of the third compartment and the cylindrical main body. The second compartment and the first compartment are fixedly installed on the compartment mounting surface inside the first compartment.

[0061] like Figure 1 , Figure 2, Figure 3 As shown, the center of mass adjustment mechanism is located at the connection between the hemispherical top of the third cabin and the cylindrical main body. A circular center of mass adjustment surface is provided at this connection, and the mechanism is mounted on this surface. The mechanism includes a circular guide rail and multiple center of mass adjustment blocks arranged on the guide rail, with at least three blocks. Each block has the same mass and is evenly spaced along the circumference of the guide rail. A motor for driving the center of mass adjustment blocks is located at the center of the center of mass adjustment surface. When the cabin moves in a microgravity environment, a high-precision gyroscope senses the cabin's three-dimensional attitude changes in real time and transmits the signals to the control system. After processing by the control system, if a deflection or rollover tendency is detected, the control system immediately drives the motor to move the corresponding center of mass adjustment block along the circular guide rail. By adjusting the mass distribution, the center of mass position of the cabin is dynamically compensated, effectively counteracting the deflection torque and ensuring that the cabin maintains a stable descent attitude throughout the entire microgravity window.

[0062] like Figure 1 , Figure 2 , Figure 3 As shown, the second chamber is used to monitor the first chamber. Specifically, the laser head can be freely adjusted in three-dimensional space through a manual or automatic three-dimensional motion adjustment structure, which includes an a-axis, a b-axis, and a c-axis. In use, the a-axis is used to adjust the defocusing amount of the laser head, and the b-axis and c-axis are used to adjust the relative interaction position of the laser and the wire. In this case, by adjusting the position of the laser head through the a, b, and c axes, the laser is irradiated at point M on the substrate, which is the metal wire forming point. The second chamber is a protective gas environment or an atmospheric environment. This protective gas environment or atmospheric environment allows the laser energy source, high-speed photography and thermal imaging monitoring devices, and solid-state batteries installed in the second chamber to operate without the technical barriers of vacuum environment applicability. Experiments can be carried out using conventional products. The laser energy source is a fiber laser or a semiconductor laser.

[0063] The first chamber is a high-vacuum / controllable atmosphere, extreme temperature simulation, and additive manufacturing chamber. The outer wall of the first chamber is made of acrylic or metal, and optical protective lenses are installed at the laser incident position, high-speed photography observation position, and thermal imager observation position. The protective lenses are used to transmit the laser from the second chamber and the corresponding optical signals used for observation. Before the experiment, the chamber is evacuated to a high vacuum (e.g., 10⁻³ to 10⁻⁵ Pa) or filled with a protective gas of a predetermined composition (e.g., Ar, He). The wire feeding mechanism of the first chamber adopts a precision metal wire feeding device. The wire material can be conventional titanium alloy, aluminum alloy, high-temperature alloy, or other crystalline metals, with a diameter range of 0.2 to 2.0 mm.

[0064] The molding substrate of the first compartment is preferably a wide-temperature-range active temperature-controlled substrate; the wide-temperature-range active temperature-controlled substrate can precisely control the substrate temperature within a range of -40°C to +400°C or wider, and is used to simulate extreme temperatures in space or study the effect of temperature gradients on molding; the wide-temperature-range active temperature-controlled substrate is prepared by a multi-temperature control mode splicing scheme and has a multi-layer structure; the wide-temperature-range active temperature-controlled substrate can be an integral design or a detachable design. When the wide-temperature-range active temperature-controlled substrate is a detachable design, the conventional molding substrate can be installed on the wide-temperature-range active temperature-controlled base.

[0065] like Figure 5 As shown, the wide-temperature-range active temperature-controlled substrate of the first chamber comprises a three-layer structure: a surface layer, a middle layer, and a bottom layer. The surface layer is an additive manufacturing substrate, which serves as a support platform for part manufacturing, primarily providing physical support and positioning for the additive manufacturing process. The middle layer is a combination of a semiconductor cooling plate and a heating plate. The semiconductor cooling plate includes a cooling section on top and a heat dissipation section on the bottom. The heating plate contains heating rods and thermocouples. The heating plate and the semiconductor cooling plate are horizontally separated. By setting the structure of the middle layer, the temperature of the substrate can be controlled by a program to achieve additive manufacturing under different temperature modes. The bottom layer is a heat insulation plate, which mainly isolates the direct heat transfer between the substrate and the multi-axis motion platform.

[0066] The space printing environment simulation chamber enables online monitoring, data synchronization and acquisition, and safe capture and recovery. Specifically, online monitoring includes high-speed cameras, infrared thermal imagers, and spectrometers to monitor the molten pool morphology, temperature field, and spatter behavior under microgravity in real time. Data synchronization and acquisition: All data, microgravity levels, and microgravity time during the additive manufacturing process are recorded synchronously. Safe capture and recovery: After the main chamber is recovered to the bottom, it is stably captured by pneumatic, hydraulic, or elastic buffer devices. After the experiment, the chamber can be opened to retrieve the printed sample.

[0067] A method for using a space printing simulation environment for space additive manufacturing, characterized by comprising the following steps:

[0068] Step 1, Preparation Stage: Load the metal wire into the wire feeding mechanism and install the substrate on the wide temperature range control seat; close the first chamber, evacuate or fill with protective gas, and preheat or precool the substrate to the target temperature.

[0069] Step 2, Microgravity Printing Stage: Before the cabin falls freely or undergoes microgravity simulation using electromagnetic catapults, the high-pressure inert gas cylinder and vacuum pump are removed. During the microgravity period, the laser, filament feeding mechanism, and motion mechanism are started simultaneously, and laser filament feeding additive manufacturing is performed on the substrate according to the preset path.

[0070] Step 3, Recovery and Data Acquisition Phase: After the main cabin is safely captured, it returns to normal gravity. The printed part is retrieved, and the process characteristics of laser wire feeding forming under microgravity, vacuum, and specific temperatures are analyzed using online monitoring data. In practical applications, this experimental equipment can be used to study the wetting and spreading behavior of metal wires on the substrate molten pool under microgravity; the transfer behavior of the molten metal wire end to the forming substrate under microgravity; and the wire drawing behavior at the end of the metal molten wire additive manufacturing process under microgravity.

[0071] This invention's system enables online detection, data synchronization and acquisition, and safe capture and recovery. Specifically, online monitoring includes high-speed cameras, infrared thermal imagers, and spectrometers to monitor the morphology, temperature field, and spatter behavior of the molten pool under microgravity in real time. Data synchronization and acquisition: All data, microgravity levels, and microgravity time during the additive manufacturing process are recorded synchronously. Safe capture and recovery: After the main chamber is recovered to the bottom, it is stably captured by pneumatic, hydraulic, or elastic buffer devices. After the experiment, the chamber can be opened and the printed sample can be retrieved.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A space printing environment simulation cabin for space additive manufacturing, characterized in that, include: The first, second, and third compartments are arranged sequentially from the inside out. The first, second, and third modules work together in a main experimental module that can be controlled to fall freely or undergo microgravity simulation motion via electromagnetic catapult. They integrate a full-function laser filament feeding additive manufacturing unit, a wide-temperature-range active temperature control substrate, a vacuum / atmosphere control system, and an online monitoring system, thereby completing the printing process within the microgravity time window and realizing a comprehensive ground simulation and process research of the space manufacturing environment. The third cabin is an attitude adjustment cabin, which is equipped with a center of mass adjustment mechanism, a gyroscope and an accelerometer. The center of mass adjustment mechanism is used to adjust the position of the cabin's center of mass to maintain attitude stability during free fall or electromagnetic catapult microgravity simulation motion. The gyroscope is used to sense changes in the cabin's attitude and the accelerometer is used to record the gravity level. The second compartment is used to monitor the first compartment; The second chamber is fixedly installed inside the third chamber and is used to house the laser head and monitoring devices including high-speed photography and thermal imaging. The laser head transmits data to the forming environment of the first chamber through a protective lens on the wall of the first chamber. The high-speed photography and thermal imaging can detect the additive manufacturing process in the first chamber through the protective lens. The first compartment is used for 3D printing; the first compartment is fixedly installed inside the second compartment. First compartment The system includes a forming substrate, a multi-axis motion platform, and a wire feeding mechanism. The wire feeding mechanism is used to feed the wire onto the forming substrate at a set speed. The forming substrate serves as a support platform for part manufacturing and is mainly used to provide physical support and positioning. The forming substrate is mounted on the multi-axis motion platform. The multi-axis motion platform is used to realize the multi-dimensional motion (XYZW) of the forming substrate. All drive mechanisms of the multi-axis motion platform are optimized for microgravity environments.

2. The space printing environment simulation cabin for space additive manufacturing according to claim 1, characterized in that: The third compartment includes a cylindrical main body and a hemispherical top and bottom connected to the main body. A gyroscope is installed at the highest point of the hemispherical top and a gravity accelerometer is installed at the lowest point of the hemispherical bottom. A circular compartment mounting surface is formed at the connection between the bottom of the third compartment and the cylindrical main body. The second compartment and the first compartment are fixedly installed on the compartment mounting surface inside the first compartment.

3. The space printing environment simulation cabin for space additive manufacturing according to claim 2, characterized in that: The center of gravity adjustment mechanism is located at the connection between the hemispherical top of the third cabin and the cylindrical main body. A circular center of gravity adjustment surface is provided at this connection, and the mechanism is mounted on this surface. The mechanism includes a circular guide rail and multiple center of gravity adjustment blocks arranged on the guide rail, with at least three blocks. Each block has the same mass and is evenly spaced along the circumference of the guide rail. A motor for driving the movement of the center of gravity adjustment blocks is located at the center of the adjustment surface. When the cabin moves in a microgravity environment, a high-precision gyroscope senses the cabin's three-dimensional attitude changes in real time and transmits the signals to the control system. After processing by the control system, if a deflection or rollover tendency is detected, the control system immediately drives the motor to move the corresponding center of gravity adjustment block along the circular guide rail. By adjusting the mass distribution, the position of the cabin's center of gravity is dynamically compensated, effectively counteracting the deflection torque and ensuring that the cabin maintains a stable descent attitude throughout the entire microgravity window.

4. The space printing environment simulation cabin for space additive manufacturing according to claim 1, characterized in that: The second chamber is used to monitor the first chamber. Specifically, the laser head can be freely adjusted in three-dimensional space through a manual or automatic three-dimensional motion adjustment structure, which includes an a-axis, a b-axis, and a c-axis. In use, the a-axis is used to adjust the defocus of the laser head, and the b-axis and c-axis are used to adjust the relative interaction position of the laser and the wire. In this case, by adjusting the position of the laser head through the a, b, and c axes, the laser is irradiated at point M on the substrate, which is the metal wire forming point. The second chamber is a protective gas environment or an atmospheric environment. This protective gas environment or atmospheric environment allows the laser energy source, high-speed photography and thermal imaging monitoring devices, and solid-state batteries installed in the second chamber to operate without the technical barriers of vacuum environment applicability. Experiments can be carried out using conventional products. The laser energy source is a fiber laser or a semiconductor laser.

5. A space printing environment simulation cabin for space additive manufacturing according to claim 1, characterized in that: The first chamber is a high-vacuum / controllable atmosphere, extreme temperature simulation, and additive manufacturing chamber. The outer wall of the first chamber is made of acrylic or metal, and optical protective lenses are installed at the laser incident position, high-speed photography observation position, and thermal imager observation position. The protective lenses are used to transmit the laser from the second chamber and the corresponding optical signals used for observation. Before the experiment, the chamber is evacuated to a high vacuum (e.g., 10⁻³ to 10⁻⁵ Pa) or filled with a protective gas of a predetermined composition (e.g., Ar, He). The wire feeding mechanism of the first chamber adopts a precision metal wire feeding device. The wire material can be conventional titanium alloy, aluminum alloy, high-temperature alloy, or other crystalline metals, with a diameter range of 0.2 to 2.0 mm.

6. A space printing environment simulation cabin for space additive manufacturing according to claim 1, characterized in that: The molding substrate of the first compartment is preferably a wide-temperature-range active temperature-controlled substrate; this wide-temperature-range active temperature-controlled substrate can precisely control the substrate temperature within a range of -40°C to +400°C or even wider, for simulating extreme temperatures in space or studying the effect of temperature gradients on molding; this wide-temperature-range active temperature-controlled substrate is manufactured using a multi-temperature control mode splicing scheme and has a multi-layer structure; this wide-temperature-range active temperature-controlled substrate can be an integral design or a detachable design. When the wide-temperature-range active temperature-controlled substrate is a detachable design, a conventional molding substrate can be installed on a wide-temperature-range active temperature-controlled base.

7. A space printing environment simulation cabin for space additive manufacturing according to claim 1, characterized in that: The wide-temperature-range active temperature-controlled substrate of the first chamber comprises a three-layer structure: a surface layer, a middle layer, and a bottom layer. The surface layer is an additive manufacturing substrate, which serves as a support platform for part manufacturing and mainly provides physical support and positioning for the additive manufacturing process. The middle layer is a combination of a semiconductor cooling plate and a heating plate. The semiconductor cooling plate includes a cooling section on top and a heat dissipation section on the bottom. The heating plate contains heating rods and thermocouples. The heating plate and the semiconductor cooling plate are separated from each other in the horizontal direction. By setting the structure of the middle layer, the temperature of the substrate can be controlled by a program to achieve additive manufacturing in different temperature modes. The bottom layer is a heat insulation plate, which mainly isolates the direct heat transfer between the substrate and the multi-axis motion platform.

8. A space printing environment simulation cabin for space additive manufacturing according to claim 1, characterized in that: The space printing environment simulation cabin enables online detection, data synchronization and acquisition, and safe capture and recovery. Specifically, online monitoring includes high-speed cameras, infrared thermal imagers, and spectrometers to monitor the morphology of the molten pool, temperature field, and spatter behavior under microgravity in real time. Data synchronization and acquisition: all data, microgravity levels, and microgravity time during the additive manufacturing process are recorded synchronously. Safe capture and recovery: after the main cabin is recovered to the bottom, it is stably captured by pneumatic, hydraulic, or elastic buffer devices. After the experiment, the cabin can be opened to retrieve the printed sample.

9. A method for using a space printing simulation environment for space additive manufacturing, based on any one of claims 1-8, characterized in that, Includes the following steps, Step 1, Preparation Stage: Load the metal wire into the wire feeding mechanism and install the substrate on the wide temperature range control seat; close the first chamber, evacuate or fill with protective gas, and preheat or precool the substrate to the target temperature. Step 2, Microgravity Printing Stage: Before the cabin falls freely or undergoes microgravity simulation motion using electromagnetic catapults, the high-pressure inert gas cylinder and vacuum pump are removed. During the microgravity period when the cabin enters the microgravity period, the laser, filament feeding mechanism and motion mechanism are started simultaneously, and laser filament feeding additive manufacturing is carried out on the substrate according to the preset path. Step 3, Recovery and Data Acquisition Phase: After the main cabin is safely captured, it returns to normal gravity; the printed parts are retrieved, and the process characteristics of laser wire feeding forming under microgravity, vacuum, and specific temperatures are analyzed in conjunction with online monitoring data; in practical use, this experimental equipment can be used to study the wetting and spreading behavior of metal wires on the substrate molten pool under microgravity. The study investigates the transfer behavior of melt at the end of a metal wire to a formed substrate under microgravity. Studies include wire drawing behavior at the end of the metal filament additive manufacturing process under microgravity.

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