Vertical axis compensation method and device for 3D printing and computer readable storage medium

Abstract

The invention discloses a vertical axis compensation method for 3D printing, a 3D printing device and a computer readable storage medium. The vertical compensation method comprises the steps that the horizontal position of a printing head at a target grid point of a 3D printing curved surface is determined; obtaining a target vertical position and a target vertical speed of the target grid point based on the horizontal position; and performing acceleration and deceleration planning on the printing head based on the current vertical position, the current speed, the target vertical position and the target vertical speed of the printing head at the current grid point where the 3D printing curved surface is located so as to control the printing head to smoothly move from the current grid point to the target grid point in the vertical direction. By means of the vertical axis compensation method for 3D printing, the vertical extraction compensation speed of 3D printing can be smoother, the extrusion synchronism effect is better, and therefore the processing efficiency of 3D printing is improved.

Description

Technical Field

[0001] This application relates to the field of 3D printing technology, and particularly relates to a vertical axis compensation method for 3D printing, a 3D printing device, and a computer-readable storage medium. Background Art

[0002] 3D printing is a technology that constructs objects by layer-by-layer printing using powdered metals or plastics and other bondable materials based on digital model files. 3D printing is usually achieved by using a digital technology material printer, and this technology has been applied in various fields such as the medical industry, education, and geography.

[0003] 3D printing is performed layer by layer on the printing platform by a print head. After each layer of the 3D printing surface is printed, the printing platform moves down one layer in the Z-axis direction, and then the print head prints the next layer of the 3D printing surface. However, leveling compensation is required during the printing process of each layer of the 3D printing surface. The currently adopted solution is to perform a linear interpolation motion on the vertical axis to make the print head accurately reach the compensation position. However, this solution will cause the horizontal movement of the print head to pause, and the frequent pauses in the horizontal movement of the print head will lead to problems such as reduced extrusion synchronization and reduced processing efficiency. Summary of the Invention

[0004] This application proposes a vertical axis compensation method for 3D printing, a 3D printing device, and a computer-readable storage medium to improve the extrusion synchronization and processing efficiency of 3D printing.

[0005] In a first aspect, this application provides a vertical axis compensation method for 3D printing. The vertical axis compensation method includes: determining the horizontal position of the target grid point of the print head on the 3D printing surface; obtaining the target vertical position and target vertical speed of the target grid point based on the horizontal position; performing acceleration and deceleration planning on the print head based on the current vertical position, current speed, target vertical position, and target vertical speed of the print head at the current grid point on the 3D printing surface to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction.

[0006] Wherein, before the step of determining the horizontal position of the target grid point of the print head on the 3D printing surface, it further includes: obtaining multiple three-dimensional coordinate points of the target printing surface; performing interpolation processing based on the multiple three-dimensional coordinate points to obtain the 3D printing surface.

[0007] Wherein, the step of obtaining the target vertical position and target vertical speed of the target grid point based on the horizontal position includes: calculating the target vertical position based on the horizontal position and the 3D printing surface; taking the derivative of the target vertical position to obtain the target vertical speed of the print head.

[0008] Among them, the steps of performing acceleration and deceleration planning on the print head based on the current vertical position, current speed, target vertical position, and target vertical speed of the print head at the current grid point on the 3D printing surface to control the smooth movement of the print head from the current grid point to the target grid point in the vertical direction include: obtaining the position deviation of the print head based on the current vertical position and the target vertical position; obtaining the deviation elimination speed of the print head based on the current speed and the target vertical speed; performing acceleration and deceleration planning on the print head based on the position deviation and the deviation elimination speed to control the smooth movement of the print head from the current grid point to the target grid point in the vertical direction.

[0009] Among them, the steps of performing acceleration and deceleration planning on the print head based on the position deviation and the deviation elimination speed include: performing speed planning on the print head based on the position deviation and the deviation elimination speed to obtain the planned speed of the print head; calculating the sum of the planned speed and the target vertical speed to obtain the control speed of the print head, and setting it as the speed of the print head in the next printing cycle.

[0010] Among them, the steps of performing acceleration and deceleration planning on the print head based on the position deviation and the deviation elimination speed further include: integrating the control speed to obtain the vertical position of the print head in the next printing cycle.

[0011] Among them, the steps of performing speed planning on the print head based on the position deviation and the deviation elimination speed include: obtaining a speed planning curve; obtaining the input state of the print head based on the position deviation and the deviation elimination speed; in response to the coordinates corresponding to the input state not being on the speed planning curve, adjusting the speed of the print head to increase or decrease at a preset acceleration until the coordinates obtained after adjustment are on the speed planning curve, and then controlling the coordinates to change along the speed planning curve.

[0012] Among them, the speed planning curve includes a T-shaped speed planning curve and an S-shaped speed planning curve.

[0013] In a second aspect, the present application provides a 3D printing device, which includes a horizontal position acquisition module, a grid curve calculation module, and a speed closed-loop planning module. The horizontal position acquisition module is used to determine the horizontal position of the print head at the target grid point on the 3D printing surface; the grid curve calculation module is used to perform acceleration and deceleration planning on the print head based on the current vertical position, current speed, target vertical position, and target vertical speed of the print head at the current grid point on the 3D printing surface to control the smooth movement of the print head from the current grid point to the target grid point in the vertical direction.

[0014] In a third aspect, the present application provides a computer-readable storage medium, which stores program instructions internally, and the program instructions are executed to implement the above-mentioned vertical axis compensation method.

[0015] The beneficial effects of the present application are as follows: The 3D printing vertical axis compensation method of the present application first determines the horizontal position of the target grid point of the print head on the current 3D printing surface; then obtains the target vertical position and target vertical speed of the target grid point based on the horizontal position; finally, performs acceleration and deceleration planning on the print head based on the current grid point, current speed, target vertical position and target vertical speed of the print head on the 3D printing surface, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction. In the above manner, the 3D printing vertical axis compensation method of the present application can prevent 3D printing from pausing during horizontal movement and avoid impacts at nodes during follow-up movement, thereby making the vertical axis compensation speed of 3D printing in the present application smoother, improving the extrusion synchronization effect, and enhancing the processing efficiency of 3D printing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for description in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. Among them:

[0017] Figure 1 is a schematic flowchart of the first embodiment of the 3D printing vertical axis compensation method of the present application;

[0018] Figure 2 is Figure 1 a specific flowchart of an embodiment of step S102 in

[0019] Figure 3 is Figure 1 a specific flowchart of an embodiment of step S103 in

[0020] Figure 4 is Figure 3 a specific flowchart of an embodiment of step S301 in

[0021] Figure 5 is Figure 4 a specific flowchart of an embodiment of step S401 in

[0022] Figure 6 is a schematic diagram of an embodiment of the T-shaped speed planning curve of the present application;

[0023] Figure 7 is a schematic flowchart of the second embodiment of the 3D printing vertical axis compensation method of the present application;

[0024] Figure 8 is a schematic structural diagram of the first embodiment of the 3D printing device of the present application;

[0025] Figure 9 It is a schematic structural diagram of the second embodiment of the 3D printing device of the present application;

[0026] Figure 10 It is a schematic structural diagram of an embodiment of the computer-readable storage medium of the present application. Detailed implementation manners

[0027] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0028] 3D printing is a technology that constructs objects by layer-by-layer printing using powdered metals, plastics, or other bondable materials based on digital model files. 3D printing is usually achieved by using a digital technology material printer, and this technology has been applied in various fields such as the medical industry, education, and geography.

[0029] 3D printing is performed layer by layer on the printing platform by the print head. After each layer of the 3D printing surface is printed, the printing platform moves down one layer in the Z-axis direction, and then the print head prints the next layer of the 3D printing surface. However, during the process of printing each layer of the 3D printing surface, leveling compensation needs to be performed. The currently adopted solution is to make the vertical axis perform a linear interpolation movement so that the print head accurately reaches the compensated position. However, this solution will cause the print head to pause during horizontal movement, and the frequent pauses in the horizontal movement of the print head will lead to problems such as reduced extrusion synchronization and reduced processing efficiency.

[0030] To solve the above problems, the present application first proposes a vertical axis compensation method for 3D printing. Please refer to Figure 1 , Figure 1 It is a schematic flowchart of the first embodiment of the vertical axis compensation method for 3D printing of the present application. As Figure 1 shown, the vertical axis compensation method for 3D printing in this embodiment specifically includes steps S101 to S103:

[0031] Step S101: Determine the horizontal position of the target grid point of the print head on the 3D printing surface.

[0032] In this embodiment, when the print head of the 3D printer prints a 3D printing surface of a certain layer, it is controlled according to discrete time. Before controlling the print head to move from the current grid point at the current position of the 3D printing surface to the next target grid point, it is first necessary to determine the horizontal position of the target grid point. In this embodiment, the horizontal position of the target grid point can be the horizontal axis coordinate position and the vertical axis coordinate position of the target grid point.

[0033] Step S102: Obtain the target vertical position and target vertical velocity of the target grid point based on the horizontal position.

[0034] After determining the horizontal position of the target grid point on the current 3D printing surface of the print head, the target vertical position of the print head at the target grid point can be calculated based on the horizontal position of the target grid point and the surface equation of the 3D grid surface. In addition, by taking the derivative of the target vertical position, the target vertical velocity corresponding to the target grid point can be obtained.

[0035] Step S103: Perform acceleration and deceleration planning on the print head based on the current vertical position, current velocity of the print head at the current grid point on the 3D printing surface, and the target vertical position and target vertical velocity, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction.

[0036] During the 3D printing process, when the print head moves from the current grid point on the 3D printing surface to the next target grid point, the current vertical position of the print head is the position of the print head in the vertical direction at the current grid point at the current moment, and the current velocity of the print head is the velocity of the print head in the vertical direction at the current grid point at the current moment and the velocity of the print head in the horizontal direction at the current grid point.

[0037] At this time, based on the difference between the current vertical position and the target vertical position of the print head and the difference between the current velocity and the target vertical velocity, the acceleration and deceleration planning of the print head can be performed to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction during printing, that is, to control the print head to start moving from the current grid point and finally reach the horizontal position and target vertical position of the target grid point at the same time. Among them, the acceleration and deceleration planning can enable the print head to have a motion ability within the system limit (specified maximum jerk, maximum acceleration, maximum speed limit, etc.) under a specified acceleration and deceleration type during the control period, and after the acceleration and deceleration closed-loop operation, the motion trajectory of the print head always tends to the target vertical position in the vertical direction, and when the velocity tends to the target vertical velocity, the position deviation between the print head and the target vertical position is 0. Among them, the specific scheme of the acceleration and deceleration planning is described below and will not be elaborated here.

[0038] Different from the prior art, the vertical axis compensation method for 3D printing in this application first determines the horizontal position of the target grid point of the print head on the current 3D printing surface; then obtains the target vertical position and target vertical speed of the target grid point based on the horizontal position; finally, performs acceleration and deceleration planning on the print head based on the current grid point where the print head is located on the 3D printing surface, the current speed, and the target vertical position and target vertical speed, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction. In the above manner, the vertical axis compensation method for 3D printing in this application can prevent the 3D printing from pausing during horizontal movement and also avoid the impact at the nodes during follow-up movement, thereby making the vertical axis compensation speed more fluent during 3D printing in this application, achieving better extrusion synchronization effect, and improving the processing efficiency of 3D printing.

[0039] Optionally, the method for obtaining the target vertical position and target vertical speed of the target grid point based on the horizontal position is as Figure 2 shown, please refer to Figure 2 , Figure 2 is Figure 1 a schematic diagram of the specific process of an embodiment of step S102 in Figure 2 shown. As Figure 2 shown, this embodiment can implement step S102 through the method shown in

[0040] Step S201: Calculate the target vertical position based on the horizontal position and the 3D printing surface.

[0041] As described above, when printing a certain 3D printing surface and controlling the print head to move to one target grid point after another, before moving, it is first necessary to determine the horizontal position of the next target grid point. Among them, the horizontal position includes the horizontal axis coordinate position and the vertical axis coordinate position. At this time, the horizontal position of the target grid point is denoted as [X(n), Y(n)], where X(n) is the horizontal axis coordinate position of the print head and Y(n) is the vertical axis coordinate position of the print head. Then, using the obtained surface equation of the 3D printing surface and substituting the horizontal position of the target grid point into this surface equation, the target vertical position Z(n) can be obtained, where Z(n) = f(X(n), Y(n)).

[0042] Step S202: Take the derivative of the target vertical position to obtain the target vertical speed of the print head.

[0043] After obtaining the target vertical position Z(n), taking the derivative of the target vertical position can obtain the target vertical speed of the print head Among them, the specific calculation formula is as follows:

[0044]

[0045] Among them, and are the differentials in the horizontal and vertical axis directions of the 3D printed surface at the horizontal position coordinates [X(n), Y(n)] of the target grid point, and are the speeds in the horizontal and vertical axis directions. When the speeds of the print head in the horizontal and vertical axis directions are known, the target vertical speed of the print head can be obtained based on the above calculation formula.

[0046] Optionally, the method for planning the acceleration and deceleration of the print head is as Figure 3 shown. Please refer to Figure 3 , Figure 3 which Figure 1 is a schematic diagram of the specific process of an embodiment of step S103 in Figure 3 As shown in Figure 3 , this embodiment can implement step S103 through the method shown in

[0047] Step S301: Obtain the position deviation of the print head based on the current vertical position and the target vertical position.

[0048] After obtaining the target vertical position of the print head moving to the target grid point, the current vertical position of the print head can be obtained, and by calculating the difference between the current vertical position and the target vertical position, the position deviation of the print head from the target vertical position can be obtained.

[0049] Step S302: Obtain the deviation elimination speed of the print head based on the current speed and the target vertical speed.

[0050] After obtaining the target vertical speed of the print head moving to the target grid point, the current speed of the print head can be obtained, and by calculating the difference between the current speed and the target vertical speed, the deviation elimination speed between the current speed and the target vertical speed of the print head can be obtained.

[0051] Step S303: Perform acceleration and deceleration planning on the print head based on the position deviation and the deviation elimination speed to control the print head to smoothly move vertically to the target grid point.

[0052] At this time, after obtaining the position deviation and the deviation elimination speed, the two can be input into the acceleration and deceleration planning module for acceleration and deceleration planning, so that after the print head runs in a closed loop, the motion trajectory always tends to the target vertical position, and the position deviation is 0 when the speed tends to the target vertical speed. That is, after the acceleration and deceleration planning, the print head can be controlled to smoothly move to the target grid point, that is, the print head can reach the horizontal position and the target vertical position of the target grid point at the same time. Through the above control, the vertical axis compensation method of 3D printing in this embodiment can prevent 3D printing from pausing during horizontal processing and prevent impact at the nodes of the follow-up motion.

[0053] Optionally, the method for performing acceleration and deceleration planning on the print head based on the position deviation and the deviation elimination speed is as Figure 4 shown. Please refer to Figure 4 , Figure 4 which Figure 3 is a schematic diagram of the specific process of an embodiment of step S301 in Figure 4 As shown. In this embodiment, step S301 can be implemented by the method as Figure 4 shown. The specific implementation steps include steps S401 to S403:

[0054] Step S401: Perform speed planning on the print head based on the position deviation and the deviation elimination speed to obtain the planned speed of the print head.

[0055] As described above, after obtaining the position deviation and the deviation elimination speed, in order to eliminate the position deviation and the deviation elimination speed, the two are input into the acceleration and deceleration planning module for speed planning to obtain the planned speed of the print head.

[0056] Step S402: Calculate the sum of the planned speed and the target vertical speed to obtain the control speed of the print head, and set it as the speed of the print head in the next printing cycle.

[0057] When performing speed planning on the position deviation and the deviation elimination speed, closed-loop control is required. That is, after obtaining the planned speed, it is necessary to calculate the sum of the planned speed and the target vertical speed to obtain the control speed of the print head after one acceleration and deceleration planning, and set the control speed as the speed of the print head in the next printing cycle and subtract it from the target vertical speed again to obtain the deviation elimination speed for the next acceleration and deceleration planning. After the acceleration and deceleration closed-loop control is completed, the planned speed approaches 0 infinitely, and the control speed of the print head approaches the vertical target speed infinitely.

[0058] Step S403: Integrate the control speed to obtain the vertical position of the print head in the next printing cycle.

[0059] After obtaining the planned speed and calculating the control speed of the print head, an integration module can be applied to integrate the control speed to obtain the vertical position of the print head in the next printing cycle, and then subtract the vertical position of the print head from the target vertical position again to obtain the position deviation for the next acceleration / deceleration planning. After the acceleration / deceleration closed-loop control is completed, the position of the print head approaches the target vertical position infinitely.

[0060] Optionally, based on the position deviation and the deviation elimination speed, speed planning is performed on the print head to obtain the planned speed of the print head as Figure 5 shown, please refer to Figure 5 , Figure 5 is Figure 4 a schematic diagram of the specific process of an embodiment of step S401 in Figure 5 shown. As Figure 5 shown, this embodiment can implement step S401 through the method shown in

[0061] Step S501: Obtain the speed planning curve.

[0062] When obtaining the planned speed of the print head, the position deviation and the deviation elimination speed need to be input into the acceleration / deceleration planning module for speed planning. Among them, the function of the acceleration / deceleration planning module is to specify that under a certain acceleration / deceleration type, the motion ability within the control period will not exceed the system limit (specified maximum jerk, maximum acceleration, maximum speed limit, etc.), and the output planned speed meets the system limit requirements.

[0063] In this embodiment, the purpose of the acceleration / deceleration planning module of this embodiment is to make the motion trajectory of the print head always tend to the target vertical position, the planned speed tends to 0, and the position deviation also tends to 0.

[0064] Among them, the acceleration / deceleration planning module includes multiple different acceleration / deceleration types, and each acceleration / deceleration type has a corresponding speed planning curve. Among them, the speed planning curve includes but is not limited to the T-type speed planning curve and the S-type speed planning curve.

[0065] In this embodiment, when performing acceleration / deceleration planning on the speed of the print head, it is first necessary to obtain the speed planning curve in the acceleration / deceleration planning module. Among them, the horizontal axis of the speed planning curve represents the position, and the vertical axis represents the speed.

[0066] Step S502: Obtain the input state of the print head based on the position deviation and the deviation elimination speed.

[0067] After obtaining the speed planning curve, the input state of the print head is obtained based on the position deviation and the deviation elimination speed, that is, the two are combined into a coordinate, and the position relationship between the coordinate and the speed planning curve is judged.

[0068] Step S503: In response to the coordinates corresponding to the input state not being on the velocity planning curve, adjust the velocity of the print head to increase or decrease at a preset acceleration until the coordinates obtained after adjustment are on the velocity planning curve, and then control the coordinates to change along the velocity planning curve.

[0069] The acceleration and deceleration planning module adjusts the velocity of the print head to increase or decrease at a preset acceleration in response to the coordinates corresponding to the input state not being on the velocity planning curve, until the coordinates obtained after adjustment are on the velocity planning curve, and then controls the coordinates to change along the velocity planning curve.

[0070] Among them, the preset acceleration can be the maximum acceleration in the module.

[0071] In an application scenario, taking the T-shaped velocity planning curve as an example, please refer to Figure 6 , Figure 6 which is a schematic diagram of an embodiment of the T-shaped velocity planning curve of the present application. As Figure 6 shown, the T-shaped velocity planning curve is a state (position, velocity) process curve that starts from a velocity of 0 and accelerates at a T-shaped preset acceleration. The horizontal axis represents the position, and the vertical axis represents the velocity. When performing acceleration and deceleration planning on the print head, it is first necessary to determine the position of the coordinates corresponding to the input state. If it is above the curve, control the velocity of the print head to start decreasing at a preset acceleration. If the input state is below the curve, the velocity starts increasing at a preset acceleration until it touches the acceleration and deceleration curve and then moves along the curve. In this way, the acceleration of the entire movement process of the print head can be controlled. As long as the state obtained according to the cycle time from the input state along the curve is the output state. In this embodiment, the input state is: the position in the nth cycle is 0, and the velocity in the nth cycle is variable E; the target state (the final equilibrium state) is that the position is variable D and the velocity is 0, and the output of the acceleration and deceleration planning module is the state (position and velocity) after the cycle time.

[0072] Optionally, based on the above embodiment, please refer to Figure 7 , Figure 7 which is a schematic flowchart of the second embodiment of the vertical axis compensation method for 3D printing of the present application. As Figure 7 shown, the vertical axis compensation method for 3D printing in this embodiment specifically includes steps S601 to S605:

[0073] Step S601: Obtain multiple three-dimensional coordinate points of the target printing surface.

[0074] In this embodiment, an external sensor can be used to scan the actual curved surface of the 3D printing. The actual curved surface is the target printing curved surface. Multiple three-dimensional points corresponding to the vertical direction positions formed by the matrix points in the horizontal axis direction and the vertical axis direction of the target printing curved surface can be obtained through the readings of the external sensor. The external sensor can be a laser sensor or other sensors, which is not limited herein.

[0075] Step S602: Perform interpolation processing based on multiple three-dimensional coordinate points to obtain the 3D printing curved surface.

[0076] After obtaining multiple three-dimensional coordinate points of the target printing curved surface of the 3D printing, perform interpolation processing on the multiple three-dimensional coordinate points to obtain the 3D printing curved surface Z, where Z = f(X, Y).

[0077] Step S603: Determine the horizontal position of the print head at the target grid point of the 3D printing curved surface.

[0078] Step S603 is the same as step S101 and will not be elaborated herein.

[0079] Step S604: Obtain the target vertical position and target vertical speed of the target grid point based on the horizontal position.

[0080] Step S604 is the same as step S102 and will not be elaborated herein.

[0081] Step S605: Perform acceleration and deceleration planning on the print head based on the current grid point, current speed, target vertical position, and target vertical speed of the print head on the 3D printing curved surface to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction.

[0082] Step S605 is the same as step S103 and will not be elaborated herein.

[0083] Optionally, the present invention further provides a 3D printing device. Please refer to Figure 8 , Figure 8 is a schematic structural diagram of the first embodiment of the 3D printing device of the present application. As Figure 8 shown, the 3D printing device 100 of this embodiment includes a horizontal position acquisition module 10, a grid curve calculation module 20, and a speed closed-loop planning module 30.

[0084] Among them, the horizontal position acquisition module 10 is used to determine the horizontal position of the print head at the target grid point of the 3D printing surface; the grid curve calculation module 20 is used to obtain the target vertical position and target vertical speed of the target grid point based on the horizontal position; the speed closed-loop planning module 30 is used to perform acceleration and deceleration planning on the print head based on the current grid point, current speed, target vertical position and target vertical speed of the print head on the 3D printing surface, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction.

[0085] In an application scenario, please refer to Figure 9 , Figure 9 which is a schematic structural diagram of the second embodiment of the 3D printing device of the present application.

[0086] As Figure 9 shown, the 3D printing device 100 of this embodiment includes a horizontal position acquisition module 10, a grid curve calculation module 20 and a speed closed-loop planning module 30. Among them, the grid curve calculation module 20 includes a grid curve speed calculation module 21 and a grid curve position module 22, and the speed closed-loop planning module 30 includes a position deviation calculation module 31, a deviation elimination speed calculation module 32, an acceleration and deceleration planning module 33, a control speed calculation module 34 and an integration module 35.

[0087] When performing vertical compensation for 3D printing, it is first necessary to obtain the 3D printing surface Z of the current 3D printing, where Z = f(X, Y). The method for obtaining the 3D printing surface can be as described above, or other methods can be used, which are not limited here.

[0088] After obtaining the 3D printing surface Z, the print head can be controlled according to the Figure 9 control process shown. Among them, in this embodiment, Figure 9 the print head is controlled according to discrete time, that is, the output forms of the state variables A to H in the control process are discrete sequences, denoted as A(n) to H(n) in the nth cycle, and n is the control cycle of the print head. The meaning of the entire control process is to obtain the output of the next control cycle, that is, after knowing A(n) and the intermediate states B(n) to G(n), to calculate H(n).

[0089] As Figure 9 shown, the horizontal position acquisition module 10 is used to obtain the horizontal position A(n) of a certain target grid point of the 3D printing surface, that is, the positions in the horizontal and vertical axis directions. Among them, A(n) is denoted as [X(n), Y(n)], and that is, in the nth cycle, the movement position of the print head in the horizontal direction is known.

[0090] After obtaining the horizontal position A(n), A(n) is respectively sent to the grid curve speed calculation module 21 and the grid curve position module 22. Among them, the grid curve speed calculation module 21 can calculate the target vertical speed C(n) based on the horizontal position [X(n), Y(n)] and the 3D printing surface equation Z = f(X, Y); the grid curve position module 22 can calculate the target vertical distance B(n) based on the horizontal position [X(n), Y(n)] and the 3D printing surface equation Z. The calculation processes of B(n) and C(n) are as follows:

[0091] B(n) = Z(n) = f(X(n), Y(n))

[0092]

[0093] Wherein, and are the differentials in the horizontal and vertical axis directions of the 3D printing surface at the horizontal position coordinates [X(n), Y(n)] of the target grid point, and are the speeds in the horizontal and vertical axis directions.

[0094] After obtaining the target vertical distance B(n) and the target vertical speed C(n), the control speed G(n) and the vertical axis position H(n) of the current print head can be obtained. The target vertical distance B(n) and the vertical axis position H(n) are input into the position deviation calculation module 31 to calculate the position deviation D(n), and the target vertical speed C(n) and the control speed G(n) are input into the deviation elimination speed calculation module 32 to calculate the deviation elimination speed E(n).

[0095] Finally, the position deviation D(n) and the deviation elimination speed E(n) are input into the acceleration and deceleration planning module 33 for acceleration and deceleration planning to obtain the planned speed F(n). Then, the planned speed F(n) and the target vertical speed C(n) are input into the control speed calculation module 34 to calculate the control speed G(n) after passing through the acceleration and deceleration planning module once. At this time, the control speed G(n) can also be sent to the deviation elimination speed calculation module 32 for secondary closed-loop control; after obtaining the control speed G(n), the integral module 35 can also perform integral processing on the control speed G(n) to obtain the vertical axis position H(n). At this time, the vertical axis position H(n) can also be sent to the position deviation calculation module 31 for secondary closed-loop control. In this embodiment, the acceleration and deceleration planning module 33 can smooth the movement trajectory of the print head under the control speed G(n), so as to ensure that no impact phenomenon occurs during the movement of the print head.

[0096] In addition, after multiple closed-loop acceleration and deceleration operations, the movement trajectory of the print head always tends to the target vertical distance B(n), and the position deviation D(n) also tends to 0 when the planned speed F(n) tends to 0.

[0097] Optionally, the present application further provides a computer-readable storage medium. Please refer to Figure 10 , Figure 10 which is a schematic structural diagram of an embodiment of the computer-readable storage medium of the present application.

[0098] The computer-readable storage medium 300 of the embodiment of the present application stores program instructions 310 internally, and the program instructions 310 are executed to implement the above-mentioned vertical axis compensation method for 3D printing.

[0099] Among them, the program instructions 310 can form a program file and be stored in the above storage medium in the form of a software product, so that an electronic device (which can be a personal computer, a server, or a network device, etc.) or a processor can execute all or part of the steps of the methods of various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes, or computers, servers, mobile phones, tablets, etc.

[0100] The computer-readable storage medium 300 of this embodiment can be, but is not limited to, a USB flash drive, an SD card, a PD optical drive, a mobile hard disk, a large-capacity floppy drive, a flash memory, a multimedia memory card, a server, etc.

[0101] In one embodiment, a computer program product or a computer program is provided. The computer program product or the computer program includes computer instructions, and the computer instructions are stored in a computer-readable storage medium. The processor of the electronic device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the electronic device executes the steps in the above method embodiments.

[0102] In addition, if the above functions are implemented in the form of software functions and sold or used as an independent product, they can be stored in a storage medium readable by a mobile terminal. That is, the present application also provides a storage device storing program data, and the program data can be executed to implement the method of the above embodiment. The storage device can be, such as, a USB flash drive, an optical disc, a server, etc. That is to say, the present application can be embodied in the form of a software product, which includes several instructions for enabling an intelligent terminal to execute all or part of the steps of the methods described in each embodiment.

[0103] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0104] Any process or method description represented in a flowchart or described otherwise herein may be understood to represent an apparatus, segment, or portion of code including one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of this application includes additional implementations, where functions may be executed in a manner not shown or discussed, including in a substantially simultaneous manner or in a reverse order according to the functions involved, which should be understood by those skilled in the technical field to which the embodiments of this application belong.

[0105] The logic and / or steps represented in a flowchart or described otherwise herein, for example, may be considered as a sequenced list of executable instructions for implementing a logical function and may be specifically implemented in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device (which may be a personal computer, server, network device, or other system that can fetch and execute instructions from the instruction execution system, apparatus, or device). For the purposes of this specification, a "computer-readable medium" may be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of the computer-readable medium include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium may even be paper or other suitable medium on which the program can be printed, as the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpretation, or other appropriate processing as necessary, and then stored in a computer memory.

[0106] The above are only the embodiments of this application and do not limit the patent scope of this application. All equivalent structural or equivalent process transformations made by using the content of the specification and drawings of this application, or directly or indirectly applied in other related technical fields, are equally included in the patent protection scope of this application.

Claims

1. A vertical axis compensation method for 3D printing, characterized in that, Including: Determine the horizontal position of the print head at the target grid point of the 3D printing surface; Obtain the target vertical position and target vertical speed of the target grid point based on the horizontal position; Perform acceleration and deceleration planning on the print head based on the current vertical position, current speed of the current grid point where the print head is located on the 3D printing surface, the target vertical position, and the target vertical speed, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction.

2. The vertical axis compensation method according to claim 1, wherein Before the step of determining the horizontal position of the print head at the target grid point of the 3D printing surface, it further includes: Obtain multiple three-dimensional coordinate points of the target printing surface; Perform interpolation processing based on the multiple three-dimensional coordinate points to obtain the 3D printing surface.

3. The vertical axis compensation method according to claim 1, wherein The step of obtaining the target vertical position and target vertical speed of the target grid point based on the horizontal position includes: Calculate the target vertical position based on the horizontal position and the 3D printing surface; Take the derivative of the target vertical position to obtain the target vertical speed of the print head.

4. The vertical axis compensation method according to claim 2, characterized in that, The step of performing acceleration and deceleration planning on the print head based on the current vertical position, current speed of the current grid point where the print head is located on the 3D printing surface, the target vertical position, and the target vertical speed, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction includes: Obtain the position deviation of the print head based on the current vertical position and the target vertical position; Obtain the deviation elimination speed of the print head based on the current speed and the target vertical speed; Perform acceleration and deceleration planning on the print head based on the position deviation and the deviation elimination speed, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction.

5. The vertical axis compensation method according to claim 4, wherein The step of performing acceleration and deceleration planning on the print head based on the position deviation and the deviation elimination speed includes: Perform speed planning on the print head based on the position deviation and the deviation elimination speed to obtain the planned speed of the print head; Calculate the sum of the planned speed and the target vertical speed to obtain the control speed of the print head, and set it as the speed for the next printing cycle.

6. The vertical axis compensation method according to claim 5, characterized in that Further includes: Integrate the control speed to obtain the vertical position of the print head for the next printing cycle.

7. The vertical axis compensation method according to claim 5, characterized in that The step of performing speed planning on the print head based on the position deviation and the deviation elimination speed includes: Obtain a speed planning curve; Obtain the input state of the print head based on the position deviation and the deviation elimination speed; In response to the coordinates corresponding to the input state not being on the speed planning curve, adjust the speed of the print head to increase or decrease at a preset acceleration until the coordinates obtained after adjustment are on the speed planning curve, and then control the coordinates to change along the speed planning curve.

8. The vertical axis compensation method according to claim 7, characterized in that, The speed planning curve includes a T-shaped speed planning curve and an S-shaped speed planning curve.

9. A 3D printing device, characterized in that, Including: A horizontal position acquisition module for determining the horizontal position of the print head at the target grid point of the 3D printing surface; A grid curve calculation module, configured to obtain a target vertical position and a target vertical speed of a target grid point based on a horizontal position; A speed closed-loop planning module, configured to perform acceleration and deceleration planning on the print head based on the current vertical position, the current speed of the print head at a current grid point on the 3D printing surface, the target vertical position, and the target vertical speed, so as to control the print head to smoothly move from the current grid point to the target grid point in the vertical direction.

10. A computer-readable storage medium, characterized in that, It internally stores program instructions, and the program instructions are executed to implement the vertical axis compensation method according to any one of claims 1-8.

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