A 3D printing system based on multi-channel adaptive printing head and method thereof

Abstract

The application discloses a kind of 3D printing system and method based on multi-channel adaptive printing nozzle, belong to 3D printing technical field.System includes control system, feed system, printing system, solidification system and motion system;Control system is based on the G code of the biological component to be printed of external input, output first displacement instruction, second displacement instruction and third displacement instruction;Feed system includes drive module group and microsyringe group, drive module group receives first displacement instruction, drives each microsyringe in microsyringe group to carry out the extrusion of biological material;Printing system includes multiple printing nozzles and a Z-axis motion module group for receiving second displacement instruction and respectively controlling the rise or fall of each printing nozzle, printing nozzle is used to carry out the printing of biological component, solidification system is used to carry out ultraviolet laser solidification to biological component;Motion system receives third displacement instruction, controls printing system to move in X, Y and Z three directions.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of biological 3D printing technology in tissue engineering, and in particular to a 3D printing system based on a multi-channel adaptive 3D printing nozzle and a method thereof. BACKGROUND

[0002] Every year, a huge number of people worldwide suffer from various types of injuries leading to tissue defects or major diseases requiring organ transplantation, resulting in a huge demand for tissue and organ repair. In particular, for end-stage organ and tissue repair, human tissue and organ transplantation is the most common treatment method. However, due to the shortage of tissue and organ donors, the immune rejection response of the recipient, culture, policy and other multiple restrictions, it is urgent to develop substitutes for tissue and organ donors. The proposal of tissue engineering opens up a new way to solve the above problems. Tissue engineering is to attach living cells to a biological material matrix or a prepared scaffold through a certain method to construct a functional tissue substitute. Then the constructed tissue substitute is cultured and implanted into the patient's body to replace the original diseased tissue and organ to restore the original body function and achieve disease treatment. The current research and use of tissue engineered skin is an effective example of the good development prospects of tissue engineering.

[0003] Biological 3D printing technology is a key technology and necessary approach to solve the shortage of tissue and organs. Biological 3D printing technology is a manufacturing method that can highly simulate biomedical structures with natural tissue characteristics. It is based on a computer three-dimensional model, uses software layering and discrete and numerical control forming methods to position and assemble biological materials or living cells, and manufactures artificial implant scaffolds, tissue organs and medical aids and other biomedical products. In modern medicine, especially in battlefield medicine, rapid and precise skin repair technology is of great significance. In battlefield environments, wounded personnel may face the risk of rapidly worsening wound infection and wound deterioration, and traditional wound repair and skin transplantation methods usually require a long recovery time and are relatively complex and time-consuming to operate. Therefore, the development of a multi-channel surface printing nozzle has great clinical and battlefield needs. With the rapid development of 3D printing technology, skin printing technology based on biological materials provides a new solution to the above problems. However, existing 3D printing devices have low printing efficiency and insufficient precision, making it difficult to meet clinical needs. Therefore, it is of great significance to design a skin printing system with high-density, multi-channel adaptive nozzle arrangement to achieve efficient and precise printing. SUMMARY

[0004] To solve the problems in the prior art, the present application proposes a 3D printing system based on a multi-channel adaptive printing nozzle and a method thereof.

[0005] The technical solutions of the present application are as follows:

[0006] In a first aspect, this invention discloses a 3D printing system based on a multi-channel adaptive printhead, comprising a control system, a feeding system, a printing system, a curing system, and a motion system. The control system outputs a first displacement command, a second displacement command, and a third displacement command based on the externally input G-code of the biological component to be printed. The feeding system includes a drive module group, a micro-injector group, and a flow sensor group. Each micro-injector in the micro-injector group is loaded with different types and concentrations of biological material. The drive module group receives the first displacement command and drives each micro-injector in the micro-injector group to extrude the biological material. The flow sensor group monitors the flow rate data of the extruded biological material from each micro-injector in real time and feeds the flow rate data back to the control system. The control system performs feedback control based on the received flow rate data. The printing system is designed to ensure that the flow rate of the biomaterial extruded by the micro-syringe reaches a preset value; wherein the biomaterial is bio-ink or cells; the printing system includes multiple printheads and a Z-axis motion module group, which receives a second displacement command to control each printhead to rise or fall; each printhead is connected to a micro-syringe and receives the biomaterial extruded by the micro-syringe, and extrudes the biomaterial from the outlet to print the bio-component; the curing system includes multiple ultraviolet laser modules arranged around the printing system, which are used to cure the bio-component with ultraviolet laser; the motion system includes an XYZ three-axis motion module; the XYZ three-axis motion module receives a third displacement command to control the printing system to move in the X, Y, and Z axes.

[0007] Secondly, this invention discloses a method for printing biological components based on a 3D printing system with a multi-channel adaptive printhead, comprising the following steps:

[0008] 1) Different types and concentrations of biological materials are installed in different micro-syringes. The micro-syringes are controlled by the control system to inject biological materials into the print head of the printing system and exhaust the air in the print head.

[0009] 2) The host computer receives the G-code of the biological component to be printed from the external input, and converts the G-code into the flow control command of the micro-injector, the position control command of the printing system as a whole, the height control command of each print head in the printing system, and the time delay command. All the obtained commands are input to the signal acquisition card group. The signal acquisition card group converts the flow control command of the micro-injector into the first displacement command and outputs it to the second linear motor group, converts the height control command of each print head in the printing system into the second displacement command and outputs it to the first linear motor group, and converts the position control command of the printing system as a whole into the third displacement command and outputs it to the XYZ three-axis motion module. At the same time, the signal acquisition card group runs the time delay command to ensure that the third displacement command, the second displacement command, and the first displacement command are executed in sequence.

[0010] 3) When a specific location of the biological component needs to be printed, the XYZ three-axis motion module moves the printing system and the Z-axis motion module to the appropriate position according to the third displacement command corresponding to that location. The motor in the first linear motor group rotates accordingly according to the second displacement command corresponding to that location, thereby driving the traction rope connected to it to move up or down, which in turn drives the capillary connected to the traction rope to move up or down. Simultaneously, the position sensor detects the position and height information of the capillary in real time and inputs the obtained position and height information to the host computer through the signal acquisition card. The host computer obtains the preset height information of the capillary based on its position and compares the height information detected by the position sensor with the preset height information. If the height information detected by the position sensor is greater than the preset height information, the linear motor is controlled to rotate forward, thereby reducing the height of the capillary. If the height information detected by the position sensor is less than the preset height information, the linear motor is controlled to rotate in reverse, thereby increasing the height of the capillary. The preset height information is the theoretical height calculated by the host computer through G-code.

[0011] 4) Once the height of the capillary is determined, the motor in the second linear motor unit rotates accordingly based on the first displacement command for printing at that position, thereby driving the connected micro-syringe to extrude biomaterial. The biomaterial enters the capillary connected to the micro-syringe, and the printing nozzle formed by the capillary prints the bio-component at that position. Simultaneously, the ultraviolet laser module cures the bio-component at that position using ultraviolet laser. At the same time, the flow sensor acquires the flow rate data of the biomaterial extruded by the micro-syringe in real time and inputs the acquired flow rate data to the host computer via a signal acquisition card. The host computer compares the flow rate data of each micro-syringe with a preset flow rate value. If the flow rate data is greater than the preset flow rate value, the speed of the linear motor is reduced, thereby reducing the flow rate of the biomaterial extruded by the micro-syringe. If the flow rate data is less than the preset flow rate value, the speed of the linear motor is increased, thereby increasing the flow rate of the biomaterial extruded by the micro-syringe, completing the printing of the bio-component at the current position. The preset flow rate value is the theoretical flow rate calculated by the host computer using G-code.

[0012] 5) Repeat steps 3)-4) to continue printing the next position of the biological component until the entire biological component is printed.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0014] This invention designs a 3D printing system based on a multi-channel adaptive printhead. A second linear motor group connects to each micro-injector, enabling independent control of the precise extrusion of biomaterial from each micro-injector. A first linear motor group connects to a spring-loaded capillary in each printhead, allowing independent control of the capillary's upward or downward movement along the Z-axis. With the cooperation of the two linear motor groups, independent material feeding and independent Z-axis movement are achieved during the printing process. Furthermore, this invention includes a flow sensor group for real-time monitoring of the biomaterial flow rate from each micro-injector, and a position sensor group for real-time detection of the capillary's position and height. The flow sensor group and position sensor group upload the acquired flow data and capillary position and height information to a host computer. The host computer performs feedback control based on the acquired data, changing the rotational speed and displacement of the corresponding linear motors in the two linear motor groups to obtain different biomaterial extrusion flow rates and capillary Z-axis heights, thereby ensuring that the biomaterial flow rate from the micro-injectors reaches a preset value, and that the capillary height reaches a preset value. This 3D printing system and control method solves the problems of low printing efficiency and insufficient accuracy in existing technologies. It realizes independent control of extrusion flow rate and independent control of Z-axis height for each channel in multi-channel printing. The flow control and Z-axis height control work together to ensure that the path filling adapts to the shape of the printing area during multi-channel extrusion bio-3D printing. This enables adaptive and efficient filling of complex shapes, which is of great significance for improving the printing efficiency of complex shapes, especially three-dimensional irregular shapes. Attached Figure Description

[0015] Figure 1 This is an overall structural diagram of the 3D printing system of the present invention.

[0016] Figure 2 This is a structural diagram of the printing nozzle in the 3D printing system of the present invention.

[0017] Figure 3 This is a schematic diagram of an 8×8 fixed guide device and channel numbering for a 3D printing system.

[0018] Figure 4 This is a schematic diagram of the network structure composed of capillaries in a 3D printing system.

[0019] The components include: host computer 1, signal acquisition card group 2, first driver group 3, second driver group 4, flow sensor group 5, first linear motor group 6, fixed guide device 7, traction rope 8, printing system 9, position sensor group 10, biological component 11, capillary tube 12, stepped bushing 13, first bushing 14, spring 15, and second bushing 16. Detailed Implementation

[0020] The present invention will be further described and illustrated below with reference to specific embodiments. The embodiments described are merely examples of the content of this disclosure and do not limit the scope of the invention. The technical features of each embodiment in the present invention can be combined accordingly, provided that there is no mutual conflict.

[0021] First, this invention provides a 3D printing system based on a multi-channel adaptive printhead, including a control system, a feeding system, a printing system 9, a curing system, and a motion system. The control system outputs a first displacement command, a second displacement command, and a third displacement command based on G-code generated by slicing software from an externally input model to be printed. The feeding system includes a drive module group, a micro-injector group, and a flow sensor group 5. Each micro-injector in the micro-injector group is loaded with different types and concentrations of biomaterial. The drive module group receives the first displacement command and drives each micro-injector in the micro-injector group to extrude biomaterial. The flow sensor group 5 monitors the flow rate data of the biomaterial extruded by each micro-injector in real time and feeds the flow rate data back to the control system. The control system performs feedback control based on the received flow rate data to ensure that the flow rate of the biomaterial extruded by the micro-injectors reaches a preset value. The biomaterial is bio-ink or cells. The printing system 9 includes multiple printheads arranged in an array and a Z-axis motion module group. The Z-axis motion module group receives a second displacement command, thereby controlling each printhead to rise or fall. Each printhead is connected to a micro-injector via a Teflon tube. The printhead receives the biomaterial extruded from the micro-injector and expels the biomaterial from the outlet to print the bio-component 11. The curing system includes multiple ultraviolet laser modules arranged around the printing system. The ultraviolet laser modules are used to cure the bio-component using ultraviolet laser. The motion system includes an XYZ three-axis motion module. The XYZ three-axis motion module receives a third displacement command, thereby controlling the printing system to move in the X, Y, and Z axes.

[0022] In one specific embodiment of the present invention, the system of the present invention further includes a frame, a feeding system mounted on the frame, an XYZ three-axis motion module also mounted on the frame, a printing system 9 mounted on the XYZ three-axis motion module, and multiple printing nozzles arranged in an array located directly below the Z-axis motion module group, and multiple printing nozzles arranged in an array also located below the feeding system, with the feeding system located above the Z-axis motion module group.

[0023] In one specific embodiment of the present invention, such as Figure 1As shown, the printing system 9 also includes a position sensor group 10, which includes multiple position sensors. Each position sensor in the position sensor group 10 is connected to the control system. The position sensors are installed at the discharge end of the print head. The position sensors detect the position and height information of the print head in real time and upload the obtained information to the control system. The control system performs feedback control based on the received information to make the position and height of the print head reach the preset value.

[0024] The Z-axis motion module group in the printing system 9 includes a first driver group 3, a first linear motor group 6 composed of multiple linear motors arranged in an array, and multiple traction ropes 8. The first driver group 3 includes multiple drivers, each of which is connected to a linear motor to drive the linear motor to rotate. The mover of each linear motor is connected to one end of a traction rope 8, and the other end of the traction rope 8 is connected to the print head. The first driver group is used to receive a second displacement command and drive all the linear motors in the first linear motor group 6 to rotate accordingly according to the second displacement command and generate vertical displacement. This causes the linear motors to pull up or lower the traction ropes 8 connected to them. The pulling up or lowering of the traction ropes 8 causes the print head connected to them to move up and down, realizing individual control of the movement of each print head. Initially, the linear motors are at their maximum displacement, and the traction ropes 8 are in a straight state. This position is set as the initial zero point of the printing system. At this time, the traction ropes 8 can only be lowered after being pulled up. When the linear motors rotate in the forward direction, the traction ropes are pulled up; when the linear motors rotate in the reverse direction, the traction ropes are lowered.

[0025] like Figure 1 As shown, the drive module group in the above-mentioned feeding system includes a second linear motor group and a second driver group 4. The second linear motor group is composed of multiple linear motors arranged in an array. The second driver group 4 includes multiple drivers, each of which is connected to a linear motor to drive the linear motor to rotate.

[0026] The control system includes a host computer 1 and a signal acquisition card group 2, which includes multiple multi-functional signal acquisition cards. The host computer 1 receives the G-code generated by the slicing software from the externally input model to be printed, and then converts the G-code into flow control instructions for the micro-injector, position control instructions for the entire printing system 9, and position control instructions for each print head in the printing system 9. The obtained three instructions are then input to the signal acquisition card group 2. The signal acquisition card group 2 includes multiple first multi-functional signal acquisition cards connected to the linear motors in the first linear motor group 6, multiple second multi-functional signal acquisition cards connected to the linear motors in the second linear motor group, and a third multi-functional signal acquisition card connected to the XYZ three-axis motion module. The signal acquisition card group 2 converts the position control instructions for the entire printing system 9 into displacement signals of the XYZ three-axis motion module and outputs them to the XYZ three-axis motion module. The signal acquisition card group 2 converts the flow control instructions for the micro-injector into motion pulse signals of the linear motors in the second linear motor group and outputs them to the second driver group 4. The signal acquisition card group 2 converts the position control instructions for each print head in the printing system 9 into motion pulse signals of the linear motors in the first linear motor group 6 and outputs them to the first driver group 3. The drivers in the first driver group 3 and the second driver group 4 perform ring distribution and power amplification of the motion pulse signals, causing the linear motor windings (stator) to be energized in a certain sequence, controlling the rotation of the linear motor, and ultimately realizing functions such as forward and reverse rotation control and rotation angle control of the linear motor. This allows different linear motors to produce different magnitudes of vertical displacement, thereby independently controlling the precise extrusion of biomaterial in each micro-syringe and independently controlling the upward or downward movement of each capillary in the Z-axis direction. The first multi-functional signal acquisition card (or the second multi-functional signal acquisition card) in the signal acquisition card group 2 is connected to the linear motor driver using a common cathode connection: the EN-, DIR-, and PUL- terminals of the driver are connected to the DGND terminal of the multi-functional signal acquisition card, and the EN+, DIR+, and PUL+ terminals of the driver are connected to the three DO output ports of the multi-functional signal acquisition card, respectively. The forward and reverse rotation, rotation angle, and speed control of the linear motor are controlled by the high and low level waveforms output by the DO ports. In a specific embodiment of the present invention, the number of multi-functional signal acquisition cards is six. It should be noted that the number of multi-function signal acquisition cards can be increased or decreased to meet the required digital and analog output needs; it can be 2, 3, 7, etc.

[0027] The first multi-functional signal acquisition card is also connected to each flow sensor in the flow sensor group 5. The flow data obtained by the flow sensor group 5 is uploaded to the host computer through the first multi-functional signal acquisition card. The host computer performs feedback control based on the received flow data to ensure that the flow rate of the bio-ink extruded by the micro-syringe reaches the preset flow rate value. Specifically, the host computer 1 automatically adjusts the displacement speed of the linear motor through a PID control algorithm based on the feedback flow data to maintain the predetermined flow target. This closed-loop control process ensures that the system can adjust in real time during the extrusion process to achieve stable flow control. The host computer 1 performs error analysis on the actual flow rate of each micro-syringe and the theoretical flow rate calculated by the G-code. When the actual flow rate is not equal to the theoretical flow rate, the host computer calculates the difference between the theoretical and actual flow rates. The host computer transmits the difference as a number of pulses through the signal acquisition card to the corresponding driver and linear motor. If the difference is positive, the number of pulses per unit time of the linear motor increases, the motor speed increases, and the flow rate of the bio-ink extruded by the micro-syringe increases. If the difference is negative, the number of pulses per unit time of the linear motor decreases, the motor speed decreases, and the flow rate of the bio-ink extruded by the micro-syringe decreases.

[0028] The second multi-functional signal acquisition card is also connected to each position sensor in the position sensor group 10. The position sensors detect the position and height information of the print head in real time and upload the obtained information to the host computer through the second multi-functional signal acquisition card. The host computer performs feedback control based on the received information to ensure that the position and height of the capillary tube 12 reach the preset value. The specific feedback control method is as follows: The second multi-functional signal acquisition card receives the signals corresponding to the position and height information of the print head collected by the position sensors in real time and transmits them to the host computer. The host computer obtains the preset height information of the capillary tube from the G code according to the position of the capillary tube, and performs error analysis between the height information detected by the position sensor and the preset height information. Through real-time displacement compensation, the pulse signal and direction signal of the linear motor are adjusted to achieve displacement feedback control of the position and height of each print head; that is, if the height information detected by the position sensor is greater than the preset height information, the linear motor is controlled to rotate in the forward direction, thereby reducing the height of the capillary tube; if the height information detected by the position sensor is less than the preset height information, the linear motor is controlled to rotate in the reverse direction, thereby increasing the height of the capillary tube; the preset height information is the theoretical height calculated by the host computer through the G code.

[0029] In the aforementioned printing system 9, multiple printheads are mounted in an array on a fixture. The fixture has multiple vertically arranged holes in an array, and the printheads are installed within these holes, as shown in the following specific form. Figure 2 As shown. From Figure 2As can be seen from the diagram, the printhead of the present invention includes a capillary tube 12, a first bushing 14, a second bushing 16, a spring 15, and a stepped bushing 13. The stepped bushing 13 is sleeved on the capillary tube 12 and is press-fitted with a hole in the fixing member, so that the capillary tube 12 is mounted on the fixing member. At this time, the capillary tube 12 vertically penetrates the fixing member and can move up and down relative to the fixing member. The first bushing 14 is sleeved on the capillary tube 12 located inside the fixing member and is fixed to the lower part of the capillary tube 12 located inside the fixing member. The first bushing 14 can engage with the capillary tube. The capillary tube 12 moves together; an annular inner cavity surrounding the capillary tube 12 is provided on the fixing member located above the first bushing 14, and the spring 15 is installed in the annular inner cavity. The spring 15 provides a downward elastic force to the first bushing 14 when the spring 15 is in a compressed state and the linear motor releases the traction rope 8, so that the capillary tube 12 can move downward smoothly; the second bushing 16 is interference-fitted with the capillary tube 12 located above the fixing member, and the second bushing is also provided with a hole through which the traction rope can pass, and the second bushing is connected to the other end of the traction rope through the hole. Among them, the end of the capillary tube installed with the second bushing is connected to the micro-injector, and the other end of the capillary tube serves as the capillary tube outlet. Initially, the traction rope 8 is in a straight state; the inner diameter of the capillary tube 12 is 10-800μm, the wall thickness of the capillary tube 12 is 10-500μm, and the distance between the axial center lines of two adjacent capillary tubes 12 is 40μm-3.5mm.

[0030] The ultraviolet laser modules in the curing system are also mounted on the fixing components. The number of ultraviolet laser modules is greater than or equal to four and they are evenly arranged circumferentially along the printing system. These ultraviolet laser modules move with the printing system. The wavelength of the ultraviolet light from these modules is 365-405 nm, and the irradiance is 10-300 mW / cm². 2 .

[0031] In a specific embodiment of the present invention, the capillaries 12 in the printing system 9 are arranged in an 8×8 configuration, the number of linear motors in the feeding system is 64, the number of linear motors in the Z-axis motion module group is 64, and the number of micro-injectors in the micro-injector group is 64, also arranged in an 8×8 configuration; wherein, the linear motors in the feeding system and the Z-axis motion module group can be 15 linear motors, 20 linear motors, or 25 linear motors.

[0032] The feeding system consists of 64 linear motors independently controlling the extrusion of biomaterial from 64 microsyringes. The number of linear motors and microsyringes used in the feeding system can be adjusted according to the complexity of the printed construct. Adjustment can be achieved by setting the PUL terminal voltage of the linear motors of unused microsyringes to zero, and by replacing the biomaterial in the microsyringes that need to be used with the desired biomaterial. Similarly, the Z-axis motion module group consists of 64 linear motors independently controlling 64 capillaries 12 to move up and down in the Z-axis direction, such as... Figure 4 As shown, the network structure formed by the capillaries 12 in the printing system 9 can be a regular hexagon, square, rectangle, trapezoid, triangle, or circle, etc. The number of linear motors and capillaries used in the Z-axis motion module group can be adjusted according to the complexity of the printed structure. Adjustment can be achieved by setting the PUL terminal voltage of the linear motor without moving capillaries 12 to zero. The capillaries 12 in the printing system 9 are independently detachable structures, facilitating replacement and cleaning.

[0033] In one specific embodiment of the present invention, such as Figure 3 As shown, the Z-axis motion module is mounted on a fixed guide device 7, which is shaped like an inverted truncated pyramid with a gradually decreasing cross-sectional area from top to bottom. Linear motors in the first linear motor group 6 are arranged in an array on the upper surface of the fixed guide device 7. Traction ropes 8 connected to the linear motors pass through the lower surface of the fixed guide device 7 and connect to the print head. The fixed guide device 7 has N smooth channels internally, with the channel spacing gradually decreasing from top to bottom. The minimum size of the smooth channel is equal to the distance between the axial center lines of two adjacent capillary tubes 12. Here, N is the total number of linear motors in the first linear motor group 6.

[0034] In the 3D printing system based on a multi-channel adaptive printhead of this invention, biomaterials are extruded and printed by a linear motor driving a micro-sampler piston, while capillary 12 moves along the Z-axis by the linear motor. In this embodiment, a 20-stepper motor and a 5mL micro-sampler are used. The biomaterials then enter capillary 12 through a Teflon tube. The extrusion flow rate of the micro-sampler is controlled by a host computer, with different pulse frequencies corresponding to different flow rates, thus achieving controllable flow rates for 64 channels of biomaterials. Sixty-four flow sensors are connected between the Teflon tube and capillary 12. The 64 channels of biomaterials flow through these 64 flow sensors. The flow rate values ​​collected by the flow sensor group 5, consisting of these 64 flow sensors, are read and compared by a multi-functional signal acquisition card under the control of the host computer, thereby achieving closed-loop control of the biomaterial flow rate within the pipeline. In this embodiment, the flow sensor is a liquid flow meter. When the feeding system stops feeding, the liquid flow meter returns a voltage signal of 0V, which is read by the multi-functional signal acquisition card and displayed on the host computer.

[0035] During the extrusion printing process, the Z-axis movement of the capillary tubes 12 is controlled by the host computer. The control method involves different pulse numbers corresponding to different height values, thereby achieving the upward and downward movement of the 64 capillary tubes 12 in the Z-axis direction. The maximum elastic force of the spring 15 is less than the maximum pulling force of the linear motor. In equilibrium, the linear motor displacement is zero, and the compression of the spring 15 is zero. The upward and downward movement of the capillary tubes 12 is achieved by controlling the magnitude of the reverse movement displacement of the linear motor. When the motor moves in the reverse direction, the traction rope 8 is pulled upward, and the pulling force of the traction rope 8 is greater than the elastic force of the spring 15, causing the capillary tube 12 to rise in the Z-axis direction. When the motor moves in the forward direction, the traction rope 8 is pulled downward, and the elastic force of the spring 15 acts on the first bushing 14, achieving the downward movement of the capillary tubes 12 in the Z-axis direction until equilibrium is reached. To facilitate observation of the normal state of the capillary springs 15 in the printing system 9 before extrusion printing, an LED tension sensor is installed between the traction rope 8 and the first bushing 14. When the spring 15 stabilizes, the tension sensor displays a value of 0.

[0036] In a specific embodiment of the present invention, the capillary 12 is a plastic elastic tube. When the capillary 12 comes into contact with or approaches a certain distance from the external printing plane, the position sensor transmits the height information to the control system. The control system controls the PUL terminal of the motor of the Z-axis motion module group to be at a low level, and the linear motor in the Z-axis motion module group stops working.

[0037] In this embodiment, the feeding system and Z-axis motion module group comprise 128 linear motors, all digitally controlled, along with 64 flow sensors. The second linear motor group realizes the extrusion of the biomaterial, while the first linear motor group 6 realizes the Z-axis motion of the capillary 12. Since the two linear motor groups require 256 channels of digital output control, this invention employs 32 multi-functional signal acquisition cards. Therefore, 16 acquisition cards control the extrusion of the biomaterial, and the other 16 control the Z-axis motion of the capillary 12. The extrusion of the biomaterial and the Z-axis motion of the capillary 12 are controlled by a program in a host computer, which can recognize different multi-functional signal acquisition cards. The model of the multi-functional signal acquisition cards can be changed, or the number can be increased to meet the required digital output.

[0038] This invention achieves three simultaneous controls during the printing of biomaterials delivered to capillary 12 via a micro-syringe: first, controlling the flow rate of different capillary 12s to achieve flow control; second, controlling the continuity of biomaterial extrusion to achieve continuous printing; and third, controlling the individual Z-axis movement of capillary 12 to achieve multi-channel adaptive printing. This enables simultaneous control and directional quantitative deposition of multiple materials in multi-channel extrusion printing, adapting to printing on different shapes, curved surfaces, or three-dimensional irregular surfaces. The flow control time is controllable, ensuring timely extrusion or retraction of biomaterials and preventing flow continuation.

[0039] When adjusting the flow rate, the host computer 1 sets the required extrusion flow rate and the volume of biomaterial for each of the 64 linear motors in the second linear motor group. Under the control of the host computer 1, the second linear motor group of the feeding system and the first linear motor group 6 of the Z-axis motion module cooperate with each other. When extruding, the first linear motor group 6 is in standby mode, and the second linear motor group realizes the extrusion of biomaterial. When moving, the first linear motor group 6 performs motion control of the printing system 9, and the second linear motor group is in standby mode.

[0040] In one specific embodiment of the present invention, the present invention also relates to a method for printing biological components based on a 3D printing system with a multi-channel adaptive printhead, comprising the following steps:

[0041] 1) Different types and concentrations of biological materials are installed in different micro-syringes. The micro-syringes are controlled by the control system to inject biological materials into the print head of the printing system 9 and to expel the air from the print head.

[0042] 2) The host computer receives the G-code of the biological component 11 to be printed from the external input, and converts the G-code into the flow control command of the micro-injector, the position control command of the printing system 9 as a whole, the height control command of each printing nozzle in the printing system 9, the time delay command, and the trigger condition command. All the obtained commands are input to the signal acquisition card group. The signal acquisition card group converts the flow control command of the micro-injector into the first displacement command and outputs it to the second linear motor group. It converts the height control command of each printing nozzle in the printing system 9 into the second displacement command and outputs it to the first linear motor group 6. It converts the position control command of the printing system 9 as a whole into the third displacement command and outputs it to the XYZ three-axis motion module. At the same time, the signal acquisition card group runs the time delay command to ensure that the third displacement command, the second displacement command, and the first displacement command are executed in sequence. That is, the first displacement command used for flow control is issued after a certain time delay to ensure that the printing system reaches the target position before the extrusion of biological material, i.e., the printing of biological components. At the same time, the signal acquisition card group runs the trigger condition command to ensure that the signal acquisition cards in all signal acquisition card groups are coordinated and controlled through time synchronization, synchronization flag bit or shared clock, and each command is synchronously output to all motors in the corresponding linear motor group.

[0043] 3) When a certain position of the biological component 11 needs to be printed, the XYZ three-axis motion module drives the printing system 9 and the Z-axis motion module to move together to the appropriate position according to the corresponding third displacement command when printing at that position; the motor in the first linear motor group 6 rotates accordingly according to the corresponding second displacement command when printing at that position, thereby driving the traction rope 8 connected to it to move up or down, thereby driving the capillary tube 12 connected to the traction rope 8 to move up or down; at the same time, the position sensor detects the position and height information of the capillary tube 12 in real time, and inputs the obtained position and height information to the host computer through the signal acquisition card group. The host computer obtains the preset height information of the capillary tube 12 according to the position of the capillary tube 12, and compares the height information detected by the position sensor with the preset height information. If the height information detected by the position sensor is greater than the preset height information, the linear motor is controlled to rotate in the forward direction, thereby reducing the height of the capillary tube 12; if the height information detected by the position sensor is less than the preset height information, the linear motor is controlled to rotate in the reverse direction, thereby increasing the height of the capillary tube 12; the preset height information is the theoretical height calculated by the host computer through G-code;

[0044] 4) Once the height of the capillary 12 is determined, the motor in the second linear motor unit rotates accordingly based on the first displacement command for printing at that position, thereby driving the micro-syringe connected to it to extrude biomaterial. The biomaterial enters the capillary 12 connected to the micro-syringe, and the printing nozzle formed by the capillary 12 prints the bio-component at that position. Simultaneously, the ultraviolet laser module cures the bio-component at that position with ultraviolet laser. At the same time, the flow sensor acquires the flow rate data of the biomaterial extruded by the micro-syringe in real time and inputs the acquired flow rate data to the host computer through the signal acquisition card. The host computer compares the flow rate data of each micro-syringe with the preset flow rate value. If the flow rate data is greater than the preset flow rate value, the speed of the linear motor is reduced, thereby reducing the flow rate of the biomaterial extruded by the micro-syringe. If the flow rate data is less than the preset flow rate value, the speed of the linear motor is increased, thereby increasing the flow rate of the biomaterial extruded by the micro-syringe, completing the printing of the bio-component 11 at the current position. The preset flow rate value is the theoretical flow rate calculated by the host computer through G-code.

[0045] 5) Repeat steps 3)-4) to continue printing the next position of the biological component 11 until the entire biological component 11 is printed.

[0046] The workflow is illustrated using the extrusion printing of a printing system 9 consisting of 64-channel capillary tubes 12 as an example:

[0047] Example 1

[0048] Before printing began, four cell / bio-ink materials were loaded into a 64-channel microsyringe: Material 1: Keratinocytes - sodium alginate solution, concentration 5 wt%; Material 2: Fibroblasts - sodium alginate solution, concentration 4 wt%; Material 3: Vascular endothelial cells - methacrylamide gelatin solution, concentration 5 wt%; and Material 4: Anti-inflammatory drug delivery - biodegradable sodium alginate support material, concentration 2 wt%. Material 1 is loaded into channels numbered 1, 5, 13, 17, 25, 29, 37, 41, 49, 53, and 61; Material 2 is loaded into channels numbered 2, 6, 10, 18, 22, 30, 34, 42, 46, 54, and 58; Material 3 is loaded into channels numbered 3, 7, 11, 15, 19, 27, 31, 39, 43, 47, 55, and 63; Material 4 is loaded into channels numbered 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 52, 56, 60, and 64.

[0049] The printing parameters are as follows: the print head moving speed in printing system 9 is 5 mm / s, and the extrusion flow rates are: 50 μL / s for material 1, 40 μL / s for material 2, 30 μL / s for material 3, and 20 μL / s for material 4. The ultraviolet laser module used for ultraviolet curing of the biological component 11 has an ultraviolet light wavelength of 405 nm and an ultraviolet light intensity of 240 mw / cm². 2 The compressive modulus of the resulting cell-loaded biological component 11 was 2.52 MPa. After printing, the cell viability reached 87%, and after 7 days of culture, the cell viability reached 91% compared to the cells surviving in the printed biological component 11.

[0050] Example 2

[0051] Before printing began, 64 materials were loaded into a 64-channel microsyringe; material 1: fibroblasts, concentration 3 wt%; material 2: fibroblasts, concentration 4 wt%; material 3: fibroblasts, concentration 5 wt%; material 4: fibroblasts, concentration 6 wt%; material 5: vascular endothelial cells, concentration 2 wt%; material 6: vascular endothelial cells, concentration 3 wt%; material 7: vascular endothelial cells, concentration 4 wt%; material 8: vascular endothelial cells, concentration 5 wt%; material 9: immune cells, concentration 2 wt%; material 10: immune cells, concentration 3 wt%; material 11: immune cells, concentration 4 wt%; material 12: immune cells, concentration 5 wt%; material 13: keratinocytes, concentration... 3wt%; Material 14: Keratinocytes, concentration 4wt%; Material 15: Keratinocytes, concentration 5wt%; Material 16: Keratinocytes, concentration 6wt%; Material 17: Dexamethasone-polylactic acid-glycolic acid microspheres, concentration 1wt%; Material 18: Dexamethasone-polylactic acid-glycolic acid microspheres, concentration 2wt%; Material 19: Dexamethasone-polylactic acid-glycolic acid microspheres, concentration 3wt%; Material 20: Dexamethasone-polylactic acid-glycolic acid microspheres, concentration 4wt%; Material 21: Vascular endothelial growth factor-gelatin, concentration 1wt%; Material 22: Epidermal growth factor-polylactic acid-glycolic acid microspheres, concentration 1wt%; Material 23: Epidermal growth factor-polylactic acid-glycolic acid microspheres, concentration 2wt% t%; Material 24: Epidermal growth factor-polylactic acid-glycolic acid microspheres, concentration 3wt%; Material 25: Penicillin-sodium hyaluronate, concentration 0.5wt%; Material 26: Gentamicin sulfate-polyethylene glycol, concentration 0.5wt%; Material 27: Ceftriaxone sodium-gelatin, concentration 0.5wt%; Material 28: Vancomycin-chitosan, concentration 0.5wt%; Material 29: Ibuprofen-sodium alginate solution, concentration 0.5wt%; Material 30: Acetaminophen-gelatin solution, concentration 0.5wt%; Material 31: Lidocaine-sodium hyaluronate, concentration 0.5wt%; Material 32: Ibuprofen-sodium alginate solution, concentration 1wt%; Material 33: Sodium alginate, concentration 2wt%; Material 34 Material 35: Sodium alginate, concentration 3wt%; Material 36: Sodium alginate, concentration 4wt%; Material 37: Gelatin, concentration 2wt%; Material 38: Gelatin, concentration 2wt%; Material 39: Gelatin, concentration 3wt%; Material 40: Gelatin, concentration 3wt%; Material 41: Polylactic-co-glycolic acid, concentration 1wt%; Material 42: Polylactic-co-glycolic acid, concentration 2wt%; Material 43: Polylactic-co-glycolic acid, concentration 3wt%; Material 44: Polylactic-co-glycolic acid, concentration 4wt%; Material 45: Bubble, diameter 0.6mm; Material 46: Bubble, diameter 0.8mm; Material 47: Bubble, diameter 1mm; Material 48: Bubble, diameter 1mm.2mm; Material 49: Fibroblast growth factor β, 1wt% concentration; Material 50: Fibroblast growth factor α, 1wt% concentration; Material 51: Epidermal growth factor-extracellular matrix, 1wt% concentration; Material 52: Transforming growth factor-β+ polylactic acid-glycolic acid microspheres, 1wt% concentration; Material 53: Platelet-derived proliferation factor, 0.5wt% concentration; Material 54: Platelet-derived proliferation factor, 1wt% concentration; Material 55: Platelet-derived proliferation factor, 1.5wt% concentration; Material 56: Platelet-derived proliferation factor, 2wt% concentration; Material 57 Material 58: Melatonin-methacrylamide gelatin, 1 wt% concentration; Material 59: Glutathione-sodium hyaluronate, 1 wt% concentration; Material 60: Chitosan-nano hydroxyapatite mixture, 1 wt% concentration; Material 61: Chitosan-nano hydroxyapatite mixture, 2 wt% concentration; Material 62: Hydroxyuracil-polyethylene glycol, 1 wt% concentration; Material 63: Polylactic acid-glycolic acid-gelatin, 1 wt% concentration; Material 64: Gelatin-polyethylene glycol diacrylate complex, 1 wt% concentration; Material 65: Chitosan-polyethylene glycol diacrylate, 2 wt% concentration.

[0052] The printing parameters are as follows: the printhead moving speed in printing system 9 is 5 mm / s, and the extrusion flow rates are as follows: Material 1, 40 μL / s, Material 2, 40 μL / s, Material 3, 40 μL / s, Material 4, 40 μL / s, Material 5, 40 μL / s, Material 6, 40 μL / s, Material 7, 40 μL / s, Material 8, 40 μL / s, Material 9, 40 μL / s, Material 10, 40 μL / s, Material 11, 40 μL / s, Material 12, 40 μL / s, Material 13, 40 μL / s, Material 14, 40 μL / s, Material 15, 40 μL / s, Material 16, 40 μL / s, Material 17, 30 μL / s, Material 18, 30 μL / s, Material 19... 30 μL / s, Material 20, 30 μL / s, Material 21, 30 μL / s, Material 22, 30 μL / s, Material 23, 30 μL / s, Material 24, 30 μL / s, Material 25, 35 μL / s, Material 35, 35 μL / s, Material 27, 35 μL / s, Material 28, 35 μL / s, Material 29, 40 μL / s, Material 30, 40 μL / s, Material 31, 40 μL / s, Material 32, 40 μL / s, Material 33, 40 μL / s, Material 34, 40 μL / s, Material 35, 40 μL / s, Material 36, 40 μL / s, Material 37, 40 μL / s, Material 38, 40 μL / s, Material 39, 40 μL / s, Material 40, 40 μL / s, Material 41, 20 μL / s, Material 42, 20 μL / s, Material 43, 20 μL / s, Material 44, 20 μL / s, Material 45, 10 μL / s, Material 46, 20 μL / s, Material 47, 30 μL / s, Material 48, 40 μL / s, Material 49, 30 μL / s, Material 50, 30 μL / s, Material 51, 30 μL / s, Material 52, 30 μL / s, Material 53, 45 μL / s, Material 54, 45 μL / s, Material 55, 45 μL / s, Material 56, 45 μL / s, Material 57, 25 μL / s, Material 58, 25 μL / s, Material 59, 25 μL / s, Material 60, 25 μL / s Materials 61, 35 μL / s, 62, 35 μL / s, 63, 35 μL / s, 64, 35 μL / s, and materials 1-64 were loaded into channels numbered 33, 17, 61, 25, 30, 18, 62, 34, 21, 1, 13, 49, 22, 14, 2, 50, 45, 9, 5, 57, 46, 6, 10, 54, 29, 41, 37, 53, 58, 38, 42, 26, 28, 19, 39, 63, 20, 40, 64, 31, 23, 11, 7, 51, 24, 8, 12, 52, 47, 3, 15, 55, 48, 16, 4, 56, 35, 43, 59, 32, 27, 60, 44, and 36, respectively.The ultraviolet laser module used for ultraviolet curing of biological components 11 has an ultraviolet light wavelength of 405nm and an ultraviolet light intensity of 240mw / cm. 2 The resulting biological component 11 loaded with cells has a compressive modulus of 2.8 MPa. After printing, the cell viability rate reaches 90%, and after 7 days of culture, the cell viability rate reaches 95% compared to the surviving cells in the printed biological component 11. A second linear motor group consisting of 64 linear motors controls the flow rate of the extruded biological material under the control of a host computer. A first linear motor group 6 consisting of 64 linear motors adjusts the Z-axis height of the capillary 12 under the control of a host computer. If the tension sensor displays 0N, the spring 15 in the printing nozzle is in a stable state. After setting the flow rate and height of each channel, the next step is performed. Each channel consists of a micro-sampler and its connected capillary 12; therefore, there are 64 channels in this embodiment.

[0053] When material needs to be extruded from each channel, the host computer controls the multi-functional signal acquisition card to output pulse signals and direction signals to drive the corresponding linear motor in the second linear motor group through the driver. The linear motor shaft moves to generate displacement, which pushes the piston of the micro-injector to supply pressure to the nozzle.

[0054] When each channel requires Z-axis movement, the host computer controls the multi-functional signal acquisition card to output pulse and direction signals, which drive the corresponding linear motors in the first linear motor group 6 via drivers. The linear motor shafts move, generating displacement and pulling the traction rope 8 (pulling the traction rope 8 means pulling it up or down). The traction rope 8 generates tension on the capillary tube 12, while the spring 15 generates elastic force. When the tension is greater than the elastic force, i.e., when the traction rope 8 is pulled up, the capillary tube 12 rises along the Z-axis; when the tension is less than the elastic force, i.e., when the traction rope 8 is lowered, the capillary tube 12 descends along the Z-axis.

[0055] During the printing process, the host computer 1 reads and displays the flow rate value fed back by the flow sensor in real time through the multi-function signal acquisition card, and compares the difference with the theoretical value calculated based on G code in real time. If the actual flow rate is less than the theoretical value, the host computer controls the multi-function signal acquisition card to supplement the flow rate difference to the corresponding linear motor, thereby increasing the set flow rate and achieving stable and controllable actual flow rate.

[0056] The feeding system of this invention controls the flow rate of multi-channel biomaterials through a second linear motor assembly, ensuring independent operation and no interference between the channels. The Z-axis motion module group utilizes the cooperation of the first linear motor assembly 6 and spring 15 to achieve precise Z-axis lifting. Feedback control, achieved through a host computer-controlled multi-functional signal acquisition card, collects and compares signals from the flow sensor to ultimately control the ink flow. Simultaneously, the host computer-controlled multi-functional signal acquisition card collects and compares signals from the position sensor to ultimately detect Z-axis lifting. This invention realizes a multi-channel adaptive 3D printing nozzle and its control, employing 64 independent screw extrusion control and a 64-channel traction structure. This ensures independent feeding and movement of each channel of the multi-channel nozzle during bio-extrusion printing, enabling printing of different shapes and curved surfaces at high speed and precision, providing technical support for multi-channel extrusion printing bio-experiments.

[0057] The above-described embodiments are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. Those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.

Claims

1. A 3D printing system based on a multi-channel adaptive printhead, characterized in that, This includes the control system, feeding system, printing system, curing system, and motion system; The control system is used to output a first displacement command, a second displacement command, and a third displacement command based on the G-code of the biological component to be printed, which is input from an external source. The feeding system includes a drive module group, a micro-injector group, and a flow sensor group. Each micro-injector in the micro-injector group is loaded with different types and concentrations of biological materials. The drive module group is used to receive a first displacement command, thereby driving each micro-injector in the micro-injector group to extrude biological materials. The flow sensor group is used to monitor the flow rate data of the biomaterial extruded by each micro-syringe in real time and feed the flow rate data back to the control system. The control system performs feedback control based on the received flow rate data to ensure that the flow rate of the biomaterial extruded by the micro-syringe reaches the preset flow rate value; wherein, the biomaterial is bio-ink or cells; The printing system includes multiple printheads and a Z-axis motion module group. The Z-axis motion module group is used to receive a second displacement command, thereby controlling each printhead to rise or fall. Each printhead is connected to a micro-injector, which receives the biomaterial extruded from the micro-injector and extrudes the biomaterial from the outlet to print the bio-component. The curing system includes multiple ultraviolet laser modules arranged around the printing system, which are used to cure biological components with ultraviolet laser. The motion system includes an XYZ three-axis motion module; the XYZ three-axis motion module is used to receive a third displacement command, thereby controlling the printing system to move in the X, Y and Z directions.

2. The 3D printing system according to claim 1, characterized in that, The Z-axis motion module group includes a first driver group, a first linear motor group composed of multiple linear motors arranged in an array, and multiple traction ropes. The first driver group includes multiple drivers, each driver being connected to a linear motor to drive the linear motor to rotate. The mover of each linear motor is connected to one end of a traction rope, and the other end of the traction rope is connected to the print head. The first driver group is used to receive a second displacement command and drive all the linear motors in the first linear motor group to rotate accordingly and generate vertical displacement. This causes the linear motors to pull up or lower the traction ropes connected to them, and the pulling up or lowering of the traction ropes causes the print head connected to them to move up and down. Initially, the linear motors are at their maximum displacement, and the traction ropes are in a straight state. At this time, the traction ropes can only be lowered after being pulled up. When the linear motors rotate in the forward direction, the traction ropes are pulled up; when the linear motors rotate in the reverse direction, the traction ropes are lowered.

3. The 3D printing system according to claim 2, characterized in that, The plurality of printheads are mounted on a fixture in an array. The fixture has a plurality of holes arranged in an array along the vertical direction. The printheads are installed in the holes. Each printhead includes a capillary tube, a first bushing, a second bushing, a spring, and a stepped bushing. A stepped bushing is fitted onto the capillary tube and press-fitted into a hole in the fixing member, allowing the capillary tube to be mounted on the fixing member. The capillary tube then vertically penetrates the fixing member and can move up and down relative to it. A first bushing is fitted onto the capillary tube located within the fixing member and fixed to its lower part. The first bushing can move together with the capillary tube. An annular cavity surrounding the capillary tube is formed on the fixing member above the first bushing. The spring is installed within this annular cavity. The spring provides a downward elastic force to the first bushing when the spring is compressed and the linear motor lowers the traction rope, allowing the capillary to move smoothly downwards. The maximum elastic force of the spring is less than the maximum pulling force of the linear motor. The second bushing is interference-fitted with the capillary located above the fixing member, and the second bushing is also provided with a hole through which the traction rope can pass. The second bushing is connected to the other end of the traction rope through the hole. The end of the capillary that is mounted on the second bushing is connected to the micro-injector, and the other end of the capillary serves as the capillary outlet.

4. The 3D printing system according to claim 3, characterized in that, The ultraviolet laser module is also mounted on a fixed component. The number of ultraviolet laser modules is greater than or equal to four and they are evenly arranged circumferentially along the printing system. The ultraviolet laser modules move with the printing system. The wavelength of the ultraviolet light emitted by the ultraviolet laser module is 365-405nm, and the irradiance of the ultraviolet light is 10-300mw / cm². 2 .

5. The 3D printing system according to claim 3, characterized in that, The drive module group includes a second driver group and a second linear motor group. The second linear motor group is composed of multiple linear motors arranged in an array. The second driver group includes multiple drivers, each of which is connected to a linear motor in the second linear motor group to drive the linear motor to rotate.

6. The 3D printing system according to claim 5, characterized in that, The control system includes a host computer and a signal acquisition card set. The host computer is used to receive the G code of the biological component to be printed from the outside, and then convert the G code into the flow control command of the micro-injector, the position control command of the printing system as a whole, and the height control command of each printing nozzle in the printing system, and input the three commands to the signal acquisition card set. The signal acquisition card group includes multiple first multi-functional signal acquisition cards connected to the linear motors in the first linear motor group, multiple second multi-functional signal acquisition cards connected to the linear motors in the second linear motor group, and a third multi-functional signal acquisition card connected to the XYZ three-axis motion module. The signal acquisition card group converts the flow control commands of the micro-injector into first displacement commands and outputs them to the second driver group, converts the height control commands of each print head in the printing system into second displacement commands and outputs them to the first driver group, and converts the overall position control commands of the printing system into third displacement commands and outputs them to the XYZ three-axis motion module. The first multi-functional signal acquisition cards are also connected to each flow sensor in the flow sensor group. The flow sensor group uploads the obtained flow data to the host computer through the first multi-functional signal acquisition cards, and the host computer performs feedback control based on the received flow data.

7. The 3D printing system according to claim 6, characterized in that, The printing system also includes a position sensor group, which includes multiple position sensors. Each position sensor in the position sensor group is connected to a second multi-functional signal acquisition card. The position sensors are installed at the outlet of the capillary tube. The position sensors detect the position and height information of the capillary tube in real time and upload the obtained information to the host computer through the second multi-functional signal acquisition card. The host computer performs feedback control based on the received information to make the height of the capillary tube reach the preset value.

8. The 3D printing system according to claim 3, characterized in that, The capillary is connected to the micro-injector via a Teflon tube; the inner diameter of the capillary in the print head is 10-800μm, the wall thickness of the capillary is 10-500μm, and the distance between the axial centerlines of two adjacent capillary tubes is 40μm-3.5mm.

9. The 3D printing system according to claim 2, characterized in that, The Z-axis motion module group is mounted on a fixed guide device, which is in the shape of an inverted truncated pyramid with a gradually decreasing cross-sectional area from top to bottom. The linear motors in the first linear motor group are arranged in an array on the upper surface of the fixed guide device, and the traction ropes connected to the linear motors pass through the lower surface of the fixed guide device and are connected to the print head.

10. A method for printing biological components using the 3D printing system based on a multi-channel adaptive printhead as described in claim 6, characterized in that, Includes the following steps: 1) Different types and concentrations of biological materials are installed in different micro-syringes. The micro-syringes are controlled by the control system to inject biological materials into the print head of the printing system and exhaust the air in the print head. 2) The host computer receives the G-code of the biological component to be printed from the external input, and converts the G-code into the flow control command of the micro-injector, the position control command of the printing system as a whole, the height control command of each print head in the printing system, and the time delay command. All the obtained commands are input to the signal acquisition card group. The signal acquisition card group converts the flow control command of the micro-injector into the first displacement command and outputs it to the second linear motor group, converts the height control command of each print head in the printing system into the second displacement command and outputs it to the first linear motor group, and converts the position control command of the printing system as a whole into the third displacement command and outputs it to the XYZ three-axis motion module. At the same time, the signal acquisition card group runs the time delay command to ensure that the third displacement command, the second displacement command, and the first displacement command are executed in sequence. 3) When a certain position of the biological component needs to be printed, the XYZ three-axis motion module drives the printing system and the Z-axis motion module to move together to the appropriate position according to the corresponding third displacement command when printing that position; the motor in the first linear motor group rotates accordingly according to the corresponding second displacement command when printing that position, thereby driving the traction rope connected to it to move up or down, thereby driving the capillary connected to the traction rope to move up or down; at the same time, the position sensor detects the position and height information of the capillary in real time, and inputs the obtained position and height information to the host computer through the signal acquisition card group. The host computer obtains the preset height information of the capillary according to the position of the capillary, and compares the height information detected by the position sensor with the preset height information. If the height information detected by the position sensor is greater than the preset height information, the linear motor is controlled to rotate in the forward direction, thereby reducing the height of the capillary; If the height information detected by the position sensor is less than the preset height information, the linear motor is controlled to rotate in the opposite direction, thereby increasing the height of the capillary tube; the preset height information is the theoretical height calculated by the host computer through G-code. 4) Once the height of the capillary is determined, the motor in the second linear motor unit rotates accordingly based on the first displacement command when printing at that position, thereby driving the micro-syringe connected to it to extrude the biomaterial. The biomaterial enters the capillary connected to the micro-syringe, and the printing nozzle composed of the capillary prints the bio-component at that position. At the same time, the ultraviolet laser module cures the bio-component at that position with ultraviolet laser. Simultaneously, the flow sensor acquires the flow rate data of the biomaterial extruded by the micro-syringe in real time and inputs the acquired flow rate data to the host computer through the signal acquisition card group. The host computer compares the flow rate data of each micro-syringe with the preset flow rate value. If the flow rate data is greater than the preset flow rate value, the speed of the linear motor is reduced, thereby reducing the flow rate of the biomaterial extruded by the micro-syringe. If the flow rate is less than the preset flow rate value, the speed of the linear motor is increased, thereby increasing the flow rate of the biomaterial extruded by the micro-sampler and completing the printing of the bio-component at the current position; wherein, the preset flow rate value is the theoretical flow rate calculated by the host computer through G-code; 5) Repeat steps 3)-4) to continue printing the next position of the biological component until the entire biological component is printed.

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