3D printing device having auto-tracking function and 3D printing method

Abstract

The present invention relates to a 3D printing device having an auto-tracking function and a 3D printing method. The 3D printing device having an auto-tracking function, according to the present invention, comprises: an ejection unit comprising a nozzle that ejects ink; a transfer unit that transfers the ejection unit or a stage on which an object to be printed is seated, in the horizontal or vertical direction according to a printing path that is set based on shape information of a surface to be printed; a displacement sensing unit that is disposed on one side of the nozzle and senses, in real time, a vertical displacement of an impact point at which ink ejected from the nozzle impacts; a rotation unit that rotates the ejection unit and the displacement sensing unit together around an arbitrary point on a vertical surface formed by both the ejection unit and the displacement sensing unit; a nozzle transfer unit that moves the nozzle such that the distance between the impact point and the nozzle is kept constant, on the basis of information on the vertical displacement of the impact point obtained from the displacement sensing unit; and a control unit that controls the rotation unit such that the nozzle is disposed in a direction normal to a tangent of the printing path when printing is performed according to the printing path set by the transfer unit.

Description

3D printing device and method with auto-tracking function

[0001] The present invention relates to a 3D printing device and method having an auto-tracking function, and more specifically, to a 3D printing device and method having an auto-tracking function for printing a 3D structure on a printing surface of a 3D shape.

[0002] Bioprinting is a concept that combines 3D printing technology with biotechnology, which allows for the fabrication of artificial tissues or organs by stacking living cells into a desired shape. While the basic printing method is the same as general 3D printing, bioprinting differs in that it uses bioinks based on biocompatible polymers, biomaterials, and hydrogels to print living cells.

[0003] Recently, along with research on the development of improved bioinks, active research is being conducted on bioprinting technology that forms artificial tissues by directly spraying bioink onto affected areas of animals or humans.

[0004] However, when printing bioink directly onto a living organism, there is a problem in that it is difficult to form high-quality artificial tissue regardless of the characteristics of the bioink because the position of the living organism is unstable.

[0005] For example, even if the position of the affected area is stably fixed, minute displacement may occur due to the respiration of living organisms, etc.

[0006] These displacements cause large errors in the bioprinting process, which requires fine control ranging from tens of micrometers to several millimeters. Consequently, the bioink is not printed in the correct location and volume, which leads to a problem of reduced quality of the artificial tissue filled in the affected area.

[0007] Accordingly, a method was considered to measure the vertical displacement of the impact point where the bioink lands in real time from a sensor placed on one side of the nozzle, and to control the nozzle to move up and down according to the vertical displacement so that the distance between the nozzle and the impact point is maintained constant while printing.

[0008] However, since the sensor is positioned on one side of the nozzle and measures the displacement in an inclined direction relative to the curved impact point, it can measure the displacement at a point other than the impact point, so the distance between the nozzle and the impact point is not maintained at a constant, resulting in a problem of reduced printing accuracy.

[0009] The objective of the present invention is to solve such conventional problems and to provide a 3D printing device and a 3D printing method having an auto-tracking function that can increase printing precision even if the point of impact moves due to breathing, etc., by controlling the injection unit and the displacement sensing unit to rotate together so that the nozzle is positioned in the normal direction of the tangent of the printing path when printing is performed according to a printing path set by a transfer unit, thereby accurately measuring the height displacement of the point of impact in real time and moving the nozzle to maintain a constant distance between the point of impact and the nozzle accordingly.

[0010] The problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below.

[0011] The above objective can be achieved by a 3D printing device having an auto-tracking function, characterized in that, according to the present invention, it comprises: a spraying unit including a nozzle for spraying ink; a transfer unit that transfers the spraying unit or a stage on which an object to be printed is placed in a horizontal or vertical direction according to a printing path set based on shape information of a surface to be printed; a displacement sensing unit disposed on one side of the nozzle that detects in real time the vertical displacement of a point of impact where ink sprayed from the nozzle lands; a rotation unit that rotates the spraying unit and the displacement sensing unit together around an arbitrary point on a vertical plane formed by the spraying unit and the displacement sensing unit together; a nozzle transfer unit that moves the nozzle so that the distance between the point of impact and the nozzle is maintained constant based on information regarding the vertical displacement of the point of impact obtained from the displacement sensing unit; and a control unit that controls the rotation unit so that the nozzle is positioned in the normal direction of the tangent of the printing path when printing is performed according to a printing path set by the transfer unit.

[0012] According to the 3D printing device and 3D printing method with an auto-tracking function of the present invention as described above, there is an advantage in that the change in movement of the impact point is accurately measured in real time, so that printing precision can be maintained at a high level even if the impact point moves.

[0013] FIG. 1 is a drawing illustrating the configuration of a 3D printing device with an auto-tracking function according to one embodiment of the present invention.

[0014] Figure 2 is a photograph showing a laser sensor positioned behind the printing direction and a laser beam directed toward the point of impact on an inclined surface.

[0015] Figures 3 and 4 are diagrams illustrating that when a laser sensor is placed behind the printing direction and a laser is irradiated toward the point of impact on an inclined surface, a measurement error of the point of impact occurs.

[0016] FIG. 5 is a diagram illustrating the operation of performing printing by rotating the printer head frame along an inclined surface when performing printing along a printing path according to an embodiment of the present invention.

[0017] FIG. 6 is a diagram illustrating the sequence of a 3D printing method with an auto-tracking function according to an embodiment of the present invention.

[0018] An embodiment of the present invention discloses a 3D printing device having an auto-tracking function, comprising: a spraying unit including a nozzle for spraying ink; a transfer unit that transfers the spraying unit or a stage on which an object to be printed is placed in a horizontal or vertical direction according to a printing path set based on shape information of a surface to be printed; a displacement sensing unit disposed on one side of the nozzle that detects in real time the vertical displacement of a point of impact where ink sprayed from the nozzle lands; a rotation unit that rotates the spraying unit and the displacement sensing unit together around an arbitrary point on a vertical plane formed by the spraying unit and the displacement sensing unit together; a nozzle transfer unit that moves the nozzle so that the distance between the point of impact and the nozzle is maintained constant based on information regarding the vertical displacement of the point of impact obtained from the displacement sensing unit; and a control unit that controls the rotation unit so that the nozzle is positioned in the normal direction of the tangent of the printing path when printing is performed according to a printing path set by the transfer unit.

[0019] In this embodiment, the rotating part is equipped with the spraying unit and the displacement sensing part, and includes a printer head frame that rotates at any point as a rotation center, and the nozzle transfer part can move the spraying unit up and down in the height direction on the printer head frame.

[0020] In this embodiment, the center of rotation may be located on the extension of the center axis of the nozzle.

[0021] In this embodiment, the relative position between the injection unit and the displacement sensing unit can always be maintained in a fixed state.

[0022] In this embodiment, the ink may be a bioink.

[0023] In this embodiment, the printing surface is a body part, and the nozzle transfer unit can correct the height displacement of the body part.

[0024] In this embodiment, the displacement sensing unit may be a laser displacement sensor.

[0025] In this embodiment, a shape detection unit for identifying shape information of the surface to be printed may be further included.

[0026] Another embodiment of the present invention comprises: a step of determining the shape of a surface to be printed; a step of generating a printing path based on shape information of the surface to be printed; and a step of printing while moving a spraying unit including a nozzle that sprays ink according to the generated printing path or a stage on which an object to be printed is placed in a horizontal or vertical direction, wherein the printing step comprises a step of detecting the vertical displacement of a point of impact in real time using a displacement sensing unit disposed on one side of the nozzle and detecting the vertical displacement of a point of impact where the ink sprayed from the nozzle lands in real time; A 3D printing method having an auto-tracking function is disclosed, comprising the step of moving the nozzle so that the distance between the impact point and the nozzle is maintained constant based on information regarding the height direction displacement of the impact point obtained from the displacement sensing unit, and, when printing is performed according to the printing path set in the printing step, rotating the injection unit and the displacement sensing unit together so that the nozzle is positioned in the normal direction of the tangent of the printing path.

[0027] In this embodiment, the injection unit and the displacement sensing unit are mounted on the rotating part, and the rotating part can rotate with one point of the rotating part as the center of rotation.

[0028] In this embodiment, the center of rotation may be located on the extension of the center axis of the nozzle.

[0029] In this embodiment, the relative position between the injection unit and the displacement sensing unit can always be maintained in a fixed state.

[0030] In this embodiment, the ink may be a bioink.

[0031] Specific details of the embodiments are included in the detailed description and drawings.

[0032] The advantages and features of the present invention and the methods for achieving them will become clear by referring to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below but may be implemented in various different forms. These embodiments are provided merely to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Throughout the specification, like reference numerals refer to like components.

[0033] Hereinafter, the present invention will be described with reference to the drawings for explaining a 3D printing device with an auto-tracking function and a 3D printing method according to embodiments of the present invention.

[0034] FIG. 1 is a diagram illustrating the configuration of a 3D printing device having an auto-tracking function according to an embodiment of the present invention, FIG. 2 is a photograph showing a laser sensor placed behind the printing direction and a laser being irradiated toward the impact point on an inclined surface, FIG. 3 and FIG. 4 are diagrams explaining that a measurement error of the impact point occurs when a laser sensor is placed behind the printing direction and a laser is irradiated toward the impact point on an inclined surface, FIG. 5 is a diagram explaining the operation of performing printing while rotating the printer head frame along the inclined surface when performing printing along the printing path according to an embodiment of the present invention.

[0035] The 3D printing device having an auto-tracking function according to the present invention relates to a printing device that performs printing as a 3D structure on a surface of a 3D shape. For example, as shown in FIG. 1, it may be a 3D bioprinting device that directly prints bioink onto a defective area, i.e., a affected area (15), existing in a part of the body (10) of a living organism such as an animal or a human, to form artificial tissue on the affected area (15) for treatment. Although the following description describes a 3D bioprinting device, the technical features of the present invention are not limited thereto and can be applied to all other 3D printing devices that form a 3D structure on a surface of a 3D shape.

[0036] A 3D printing device with an auto-tracking function according to one embodiment of the present invention may include a stage (110), a shape detection unit (120), a spraying unit (130), a transfer unit (140), a displacement detection unit (150), a rotation unit, a nozzle transfer unit (170), and a control unit (180).

[0037] A 3D printing device with an auto-tracking function according to one embodiment of the present invention can treat a defect, that is, a affected area (15), that exists in a part of the body (10) of a living organism such as an animal or a human by directly printing bioink on the affected area (15) to form artificial tissue on the affected area (15).

[0038] The stage (110) is a part on which the object to be printed is placed, and may be, for example, a part on which an animal or patient having a wound (15) requiring treatment or a part of the patient's body (10) is placed. Depending on the treatment target, the stage (110) may form a bed structure, or it may form a table structure so that a small animal or a part of the body (10) can be placed.

[0039] The shape detection unit (120) identifies the shape of the printing surface of an object placed on the stage (110). That is, in this embodiment, the shape of a lesion (15) existing on a part of a patient's body (10) or an animal placed on the stage (110) can be detected.

[0040] A non-contact scanning device known as the shape detection unit (120) above may be applied. The non-contact scanning method is a method of scanning an object using light, and models the three-dimensional shape of the object by irradiating the object with light using a laser or white light and measuring the time of the reflected light to quantify the distance.

[0041] That is, the shape detection unit (120) can generate modeled shape information of a three-dimensional shape corresponding to the defective part of the affected area (15) which is in the shape of an intaglio.

[0042] The shape detection unit (120) may be fixedly positioned on the upper side of the stage (110), or it may be configured to be installed on a separate transfer unit so that it can be moved on the upper side of the stage (110). For example, if the entire upper part of the stage (110) is the detection area, the entire shape of the affected part (15) can be detected while fixed on the upper side of the stage (110), and if a part of the upper part of the stage (110) is the detection area, the entire shape of the affected part (15) can be detected while moving on the upper side of the stage (110).

[0043] The shape detection unit (120) may be configured to be transported together with the spray unit (130) by the spray unit transport unit (140) described later.

[0044] In this embodiment, the shape detection unit (120) directly identifies the shape of the surface to be printed for an object placed on the stage (110), but the shape information of the object to be printed may be identified in advance and provided as 3D design data.

[0045] The spraying unit (130) is positioned above the stage (110) and may include a nozzle (135) that sprays ink toward the printing surface of an object placed on the stage (110).

[0046] In this embodiment, the spraying unit (130) sprays bioink toward the affected area (15) of the body (10). The bioink may contain a biomaterial or cell fluid. The biomaterial may be a biocompatible polymer or a hydrogel. The cell fluid may be a cell solution containing cells, a cell culture medium, and a hydrogel.

[0047] In the drawing, one spraying unit (130) is formed, but a plurality of spraying units (130) may be formed. For example, the spraying unit (130) may include a first spraying unit provided with a first nozzle for spraying biomaterial and a second spraying unit provided with a second nozzle for spraying cell fluid.

[0048] The above bioink may be made of materials with various characteristics depending on the location or type of artificial tissue being fabricated, and is not specifically limited thereto.

[0049] The transfer unit transfers the spray unit (130) horizontally (XY plane direction) or in a height direction (Z direction) according to a printing path generated based on shape information identified from the shape detection unit (120), or transfers the stage (110) horizontally or in a height direction. In this embodiment, the transfer unit (140) transfers the spray unit (130) horizontally or in a height direction according to a printing path generated based on shape information of the affected part (15) identified from the shape detection unit (120). That is, in FIG. 1, a spray unit transfer unit (140) that transfers the spray unit (130) horizontally or in a height direction is shown.

[0050] Although not illustrated, the transfer unit may be composed of a stage transfer unit that transfers the stage (110) in a horizontal or vertical direction. Alternatively, it may be composed of a combination of a spray unit transfer unit (140) and a stage transfer unit. For example, transfer in the X-axis and Y-axis directions may be composed of a spray unit transfer unit (140), and transfer in the Z-axis direction may be composed of a stage transfer unit.

[0051] When shape information of the printing surface obtained through the shape detection unit (120), that is, shape information modeled as a shape corresponding to the defect portion of the affected part (15), is obtained, a printing path can be created and set by the spraying unit (130).

[0052] For example, bio-ink is sprayed onto a predetermined impact point on the affected area (15) to pattern a spot or line shape. A nozzle (135) that is transported together with the spraying unit (130) is moved horizontally in the horizontal (X-axis) or vertical (Y-axis) direction, or a stage (110) is moved horizontally in the horizontal or vertical direction to collect the spot or line shape patterns and form a first layer of pattern. Then, the nozzle (135) of the spraying unit (130) is raised in the height (Z-axis) direction or the stage (110) is lowered in the height direction, and a stacking process is performed to build up a second layer of pattern, thereby forming the required three-dimensional structure.

[0053] That is, the printing path by the transfer of the injection unit (130) or the stage (110) can be set as a continuous printing path from the first injection point where the bio-ink is injected to the injection end point where the defective area of ​​the affected part (15) is completely filled with bio-ink, and at this time, from the injection point to the injection end point, the nozzle (135) is set to maintain a constant height from the point of impact located within the affected part (15).

[0054] The distance between the nozzle (135) and the point of impact can be set differently depending on the type of bioink used. For example, the distance between the first nozzle of the first spraying unit that sprays biomaterial and the second nozzle of the second spraying unit that sprays cell fluid can be set differently from each other.

[0055] The above-mentioned spray unit transfer section (140) may include a horizontal transfer section that transfers the spray unit (130) in a horizontal direction parallel to the stage (110), and a vertical transfer section that moves the spray unit (130) closer to or further away from the stage (110) in a vertical direction.

[0056] Likewise, the stage transfer unit may include a horizontal transfer unit that transfers the stage (110) in a horizontal direction and a vertical transfer unit that moves the stage (110) closer to or further away from the spray unit (130) in a vertical direction.

[0057] The above-mentioned transfer unit may utilize a general linear transfer structure, such as a linear motor or a structure combining a rotary motor and a ball screw; since the configuration of such a linear transfer structure is obvious to a person skilled in the art, a detailed description is omitted.

[0058] An animal or patient placed on the stage (110) experiences vertical displacement in the affected area (15) due to breathing, rigidity, convulsions, etc., which causes vertical displacement of the impact point where the bioink ejected from the nozzle (135) reaches. The displacement occurring at the impact point of the animal or patient may be vertical displacement (Z-axis) relative to the stage (110).

[0059] For example, when exhaling, the position of the impact point relatively decreases, and when inhaling, the position of the impact point relatively increases. If bio-ink is sprayed by moving the spray unit (130) or stage (110) along only the previously set printing path without considering the displacement of the affected area (15) in the height direction due to breathing, the distance between the impact point and the nozzle (135) changes in the height direction, so the problem arises that the bio-ink discharged from the nozzle (135) cannot be accurately sprayed to the impact point.

[0060] If the distance between the impact point and the nozzle (135) becomes closer than the set distance, an artificial tissue pattern smaller than the normal pattern may be formed, and if the distance between the impact point and the nozzle (135) becomes farther, the bioink diffuses and an artificial tissue pattern larger than the normal pattern may be formed.

[0061] Therefore, if the distance between the point of impact and the nozzle (135) on the printing path changes, the uneven formation conditions of the artificial tissue may cause a problem of quality degradation during the regeneration process of the artificial tissue.

[0062] To resolve this, the present invention detects the displacement in the height direction of the point of impact where ink is deposited from the nozzle (135) in real time, and based on this, moves the nozzle (135) to maintain the distance between the point of impact and the nozzle (135) at all times while performing printing. That is, the 3D bioprinting device according to the present embodiment can improve printing quality by detecting the displacement in the height direction of the point of impact caused by the breathing of animals or patients in real time, and based on this, moves the nozzle (135) to maintain the distance between the point of impact and the nozzle (135) at all times while performing printing.

[0063] The displacement detection unit (150) is positioned on one side of the nozzle (135) and detects in real time the height direction displacement of the impact point where the ink ejected from the nozzle (135) lands. The impact point refers to the point where the ink (bio-ink) discharged from the nozzle (135) reaches the printing surface (the affected area (15)), and this can have an area of ​​tens of micrometers to several millimeters.

[0064] A laser displacement sensor may be applied to the displacement detection unit (150) above. The laser displacement sensor transmits a laser signal toward the point of impact and receives the reflected signal to measure the height displacement of the point of impact.

[0065] The spray unit (130) and the displacement detection unit (150) are mounted together on the printer head frame (160), so that when the printer head frame (160) is transported by the spray unit transport unit (140), the displacement detection unit (150) can be transported together with the spray unit (130). Since the displacement detection unit (150) is positioned on one side of the nozzle (135), it does not detect the displacement in the height direction of the impact point from the vertical upper side of the impact point, but rather measures the displacement in the inclination direction. In this case, as described later with reference to FIGS. 3 and 4, the displacement of the impact point may not be accurately measured.

[0066] The rotating part (162) rotates the injection unit (130) and the displacement sensing part (150) together. More specifically, the injection unit (130) and the displacement sensing part (150) are rotated together with any point on the vertical plane formed by the injection unit (130) and the displacement sensing part (150) as the center of rotation (C).

[0067] The above-mentioned rotating part (162) may be configured to include a printer head frame (160) and a rotary drive unit (not shown) that rotates the printer head frame (160). A spray unit (130) and a displacement detection unit (150) may be mounted on the printer head frame (160). When the printer head frame (160) is rotated by the rotary drive unit with a point on the printer head frame (160) as the center of rotation (C), the spray unit (130) and the displacement detection unit (150) can be rotated together. At this time, it is preferable that the center of rotation (C) of the printer head frame (160) lies on a straight line (L) where the axis of the nozzle (135) extends toward the printer head frame (160).

[0068] The nozzle transfer unit (170) transfers the nozzle (135) in the vertical height direction based on information regarding the height direction displacement of the impact point obtained from the displacement detection unit (150) so that the distance between the impact point and the nozzle (135) is always maintained constant.

[0069] The nozzle transfer unit (170) is formed on the printer head frame (160) and can be configured to move up and down in the height direction of the spray unit (130) on the printer head frame (170). Here, the height direction does not mean a direction perpendicular to the stage (110). This is because the nozzle (135) is positioned at an angle as the printer head frame (160) rotates. More precisely, the height direction may mean the height direction in which the axis of the nozzle (135) is directed.

[0070] For the nozzle transfer unit (170), a general linear transfer structure such as a linear motor, a rotary motor, and a ball screw combination structure may be used, and since the configuration of such a linear transfer structure is obvious to a person skilled in the art, a detailed description is omitted.

[0071] Accordingly, in this embodiment, when irradiating the bioink onto the affected area (15) of the body (10), 3D printing can be performed by correcting the height-direction displacement of the impact point in real time by taking into account the change in height-direction displacement of the impact point caused by the body (10)'s breathing, etc.

[0072] When the control unit (180) performs printing by transporting the spraying unit (130) or the stage (110) by the transport unit according to the set printing path, it controls the rotation unit according to the shape of the inclined surface being printed to rotate the displacement sensing unit (150) together with the spraying unit (130). When printing is performed according to the printing path set by the transport unit as shown in FIG. 5 (e.g., from left to right in FIG. 5), the control unit (180) can control the rotation unit so that the nozzle (135) is positioned in the normal direction of the tangent of the printing path.

[0073] Although the drawing shows that the control unit (180) controls only the rotation unit, the control unit (180) can control all operations related to the 3D printing device. That is, the control unit (180) can control the operation of the shape detection unit (120), the injection unit (130), the transfer unit, the displacement detection unit (150), the nozzle transfer unit (170), etc.

[0074] FIGS. 3 and 4 illustrate a case where printing is performed by moving the nozzle (135) from left to right on a curved printing surface of a 3D shape, and the displacement sensing unit (150) is located behind the nozzle (135).

[0075] When printing is performed on the highest point of a printing surface that is curved in a 3D shape as shown in FIG. 3, the sensor signal of the displacement detection unit (150) can be accurately directed toward the point of impact. That is, even if the displacement detection unit (150) is positioned behind the nozzle (135) with respect to the printing direction, on a rising inclined surface, the sensor signal of the displacement detection unit (150) can be accurately directed toward the point of impact on the inclined surface.

[0076] However, as shown in FIG. 4, when the nozzle (135) moves to the right, the sensor signal of the displacement detection unit (150) does not reach the point of impact vertically below the nozzle (135) with respect to the inclined surface inclined downward in the printing direction (from left to right), but the sensor signal of the displacement detection unit (150) may reach the bottom surface to the right of the point of impact. In FIG. 2, it can be seen that the actual laser displacement sensor signal is directed to the right of the point of impact rather than to the point of impact in the situation of FIG. 4.

[0077] Therefore, in this case, the displacement detection unit (150) fails to measure the height-direction displacement of the impact point vertically below the current nozzle (135) position and instead measures the height-direction displacement of another point, causing the measurement value to change suddenly. Consequently, the nozzle transfer unit (170) transfers the nozzle (135) based on the incorrectly measured value, which may result in the distance between the nozzle (135) and the impact point not being maintained constant, thereby causing a problem of reduced printing precision.

[0078] Accordingly, in the present invention, when the control unit (180) performs printing according to a set printing path, the spray unit (130) and the displacement detection unit (150) are rotated together so that the nozzle (135) faces the normal direction of the inclined surface being printed, so that no error occurs in the measurement value measured by the displacement detection unit (150).

[0079] For example, as illustrated on the left side of FIG. 5, when the normal of the tangent of the printing path (from left to right in the drawing) is directed upward to the right, the printer head frame (160) can be rotated clockwise so that the nozzle (135) is directed in the direction of the normal. Here, the printing direction does not mean the direction in which ink is ejected from the nozzle (135), but rather the direction in which ink is continuously printed along the printing path while moving the nozzle (135) or the stage (110). At this time, the sensor signal emitted from the displacement detection unit (150) positioned on one side of the nozzle (135) can be accurately emitted to the point of impact.

[0080] Likewise, as illustrated on the right side of FIG. 5, when the normal of the tangent of the printing path is directed toward the upper left, the printer head frame (160) can be rotated counterclockwise so that the nozzle (135) is directed toward the direction of the normal. Even in this case, the sensor signal irradiated from the displacement detection unit (150) positioned on one side of the nozzle (135) can be accurately irradiated at the point of impact.

[0081] Hereinafter, a 3D printing method with an auto-tracking function according to the present invention will be described.

[0082] FIG. 6 is a diagram illustrating the sequence of a 3D printing method with an auto-tracking function according to an embodiment of the present invention.

[0083] The 3D printing method with an auto-tracking function according to the present invention may include the step of identifying the shape of the surface to be printed (S210), the step of generating a printing path (S220), and the step of printing (S230).

[0084] In the step (S210) of determining the shape of the surface to be printed, the shape of the surface to be printed of the object to be printed prepared on the stage (110) is determined. In this embodiment, the shape of the affected area (15) existing on a part of the body (10) or animal prepared on the stage (110) is determined. That is, the shape detection unit (120) can be used to generate and model the three-dimensional shape information corresponding to the defective part of the affected area (15) in the form of an intaglio. Alternatively, the shape information of the object may be determined in advance and provided as 3D design data before the object to be printed is placed on the stage (110).

[0085] Next, a printing path is generated based on the shape information of the surface to be printed (S220). That is, in this embodiment, a printing path in which ink is printed is set based on the shape information of the affected area (15) obtained by the shape detection unit (120). The printing path thus set can be a continuous printing path from the initial point of injection where bio-ink is sprayed toward the affected area (15) to the end point of injection where the defective area of ​​the affected area (15) is completely filled with bio-ink.

[0086] At this time, when printing is performed along the printing path from the injection point to the injection end point, the distance between the nozzle (135) and the point of impact can be set to be maintained at a constant distance. The distance between the nozzle (135) and the point of impact can be set differently depending on the type of bioink used and the degree of defect in the affected area (15).

[0087] Next, the printing step (S230) performs printing by moving the injection unit (130) or the stage (110) in a horizontal or vertical direction according to the generated printing path. That is, in this embodiment, bio-ink is injected from the nozzle (135) according to the generated printing path to form artificial tissue.

[0088] For example, the nozzle (135) of the spraying unit (130) is moved horizontally in the horizontal (X-axis) or vertical (Y-axis) direction, or moved vertically in the height (Z-axis) direction, and the spraying unit (130) is moved along a set printing path and bio-ink is sprayed toward the affected area (15).

[0089] Thus, the displacement in the height direction of the impact point is measured in real time using a displacement detection unit (150) that detects in real time the displacement in the height direction of the impact point where the ink sprayed from the nozzle (135) lands while spraying ink. That is, in this embodiment, while spraying bio-ink toward the affected area (15), the process includes compensating for the height direction position of the nozzle (135) by taking into account the change in height direction displacement of the affected area (15) due to breathing, etc.

[0090] That is, the printing step (S230) may include a step of detecting the displacement in the height direction of the impact point in real time and a step of correcting the height direction position of the nozzle (135) so that the distance between the impact point and the nozzle (135) is maintained constant. The step of correcting the height direction position may be performed by moving the injection unit (130) up and down on the printer head frame (160) by the nozzle transfer unit (170).

[0091] At this time, in the present invention, as described with reference to FIG. 5, in the printing step (S230), when printing is performed according to a set printing path, the spraying unit (130) and the displacement sensing unit (150) are rotated so that the nozzle (135) is positioned in the normal direction of the printing path. For example, the spraying unit (130) and the displacement sensing unit (150) can be rotated together by rotating the head frame (160) on which the spraying unit (130) and the displacement sensing unit (150) are mounted, with a point on the vertical plane formed together by the spraying unit (130) and the displacement sensing unit (150) as the center of rotation. That is, in this embodiment, the spraying unit (130) and the displacement sensing unit (150) are mounted on the printer head frame (160), and the printer head frame (160) is rotated with one point of the printer head frame (160) as the center of rotation so that the spraying unit (130) and the displacement sensing unit (150) can be rotated together. Therefore, the relative positions of the spraying unit (130) and the displacement sensing unit (150) can always be maintained in a fixed state.

[0092] Therefore, since the displacement sensing unit (150) can always face the impact point in a vertical direction with respect to the inclined surface, the height displacement of the impact point can be accurately measured.

[0093] After 3D bioprinting is completed and a certain amount of time has passed, the cells contained in the bioink receive oxygen and nutrients through the diffusion of body fluids until new blood vessels are formed in most tissues or organs. Then, as blood vessels enter the body and blood supply is established, the cells proliferate and differentiate to form new tissues, and the biomaterial decomposes and disappears during this time.

[0094] The scope of the present invention is not limited to the embodiments described above but may be implemented in various forms of embodiments within the scope of the appended claims. It is deemed that the scope of the claims of the present invention includes various modifications that are possible by anyone with ordinary knowledge in the technical field to which the invention pertains, without departing from the essence of the invention claimed in the claims.

Claims

1. A spraying unit including a nozzle for spraying ink; A transfer unit that transfers the injection unit or the stage on which the object to be printed is placed in a horizontal or height direction according to a printing path set based on shape information of the surface to be printed; A displacement sensing unit disposed on one side of the nozzle and detecting in real time the height-direction displacement of the impact point where the ink sprayed from the nozzle lands; A rotating part that rotates the injection unit and the displacement sensing part together around an arbitrary point on a vertical plane formed by the injection unit and the displacement sensing part together; A nozzle transfer unit that moves the nozzle so that the distance between the impact point and the nozzle is maintained constant based on information regarding the height direction displacement of the impact point obtained from the displacement detection unit; and A 3D printing device having an auto-tracking function, comprising: a control unit that controls the rotation unit so that the nozzle is positioned in the normal direction of the tangent of the printing path when printing is performed according to the printing path set by the transfer unit.

2. In Paragraph 1, The above-mentioned rotating part is equipped with the above-mentioned spraying unit and the above-mentioned displacement sensing unit, and includes a printer head frame that rotates at an arbitrary point as a rotation center. The nozzle transfer unit is a 3D printing device having an auto-tracking function that moves the injection unit up and down in the height direction on the printer head frame.

3. In Paragraph 2, A 3D printing device with an auto-tracking function in which the rotation center is located on the extension line of the central axis of the nozzle.

4. In Paragraph 2, A 3D printing device having an auto-tracking function in which the relative positions of the injection unit and the displacement sensing unit always remain in a fixed state.

5. In Paragraph 1, The above ink is a bioink, and the device is a 3D printing device with an auto-tracking function.

6. In Paragraph 5, The surface to be printed is a affected part of the body, and the nozzle transfer unit is a 3D printing device having an auto-tracking function that corrects the height-direction displacement of the affected part.

7. In Paragraph 1, The above displacement sensing unit is a 3D printing device with an auto-tracking function that is a laser displacement sensor.

8. In Paragraph 1, A 3D printing device with an auto-tracking function that further includes a shape detection unit for identifying shape information of the surface being printed.

9. Step of determining the shape of the surface to be printed; A step of generating a printing path based on shape information of the surface to be printed; and The method includes the step of printing while moving a spraying unit including a nozzle that sprays ink according to a generated printing path, or a stage on which an object to be printed is placed, in a horizontal or vertical direction. The above printing step A step of detecting in real time the height direction displacement of the impact point using a displacement detection unit disposed on one side of the nozzle and detecting in real time the height direction displacement of the impact point where the ink sprayed from the nozzle lands; and Based on information regarding the height-direction displacement of the impact point obtained from the displacement detection unit, the method includes the step of moving the nozzle so that the distance between the impact point and the nozzle is maintained constant. A 3D printing method having an auto-tracking function, characterized by rotating the injection unit and the displacement sensing unit together so that the nozzle is positioned in the normal direction of the tangent of the printing path when performing printing according to the printing path set in the printing step.

10. In Paragraph 9, A 3D printing method having an auto-tracking function in which the above-mentioned injection unit and the above-mentioned displacement sensing unit are mounted on a rotating part, and the rotating part rotates with one point of the rotating part as the rotation center.

11. In Paragraph 10, A 3D printing method with an auto-tracking function in which the rotation center is located on the extension line of the central axis of the nozzle.

12. In Paragraph 9, A 3D printing method having an auto-tracking function in which the relative positions of the injection unit and the displacement sensing unit always remain in a fixed state.

13. In Paragraph 9, The above ink is a 3D printing method with an auto-tracking function that is a bioink.

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