阅读说明：本技术 基于Delta机械臂的光固化3D打印机切片方法、打印方法及其打印机 (Delta mechanical arm-based photocuring 3D printer slicing method, printing method and printer ) 是由 张鹏 彭国祥 孙路伟 于 2019-09-23 设计创作，主要内容包括：本发明提供一种基于Delta机械臂的光固化3D打印机切片方法,包括如下步骤：计算三维模型的高度、提取三维模型的外轮廓,根据高度数据和外轮廓曲线形状得到切片层数及其对应的切片厚度；根据切片层数、切片厚度得到每层的切片形状。再提供一种打印方法,包括步骤：实施所述的切片方法。还提供一种打印机,使用所述的打印方法。本发明的有益效果是：在分层厚度的选择上采用自适应分层,即在Z轴方向上根据物体轮廓的表面形状改变分层厚度,以满足物体表面精度的要求,该方法相比于固定厚度的切片方法,能够获得更高的加工精度。(The invention provides a Delta mechanical arm-based photocuring 3D printer slicing method, which comprises the following steps: calculating the height of the three-dimensional model, extracting the outer contour of the three-dimensional model, and obtaining the number of slicing layers and the slicing thickness corresponding to the number of slicing layers according to the height data and the shape of the curve of the outer contour; and obtaining the slice shape of each layer according to the number of the slice layers and the slice thickness. There is further provided a printing method comprising the steps of: the slicing method is implemented. A printer using the printing method is also provided. The invention has the beneficial effects that: the method adopts self-adaptive layering on the selection of the layering thickness, namely the layering thickness is changed according to the surface shape of the object contour in the Z-axis direction so as to meet the requirement of the surface precision of the object.)

1. A slicing method of a light-cured 3D printer based on a Delta mechanical arm comprises the following steps:

step S1, calculating the height of the three-dimensional model, extracting the outer contour of the three-dimensional model, and obtaining the number of slice layers and the slice thickness corresponding to the number according to the height data and the shape of the outer contour curve;

and step S2, obtaining the slice shape of each layer according to the slice layer number and the slice thickness.

2. The slicing method as claimed in claim 1, wherein the step S1 is specifically: sectioning the three-dimensional model at intervals of 45 degrees in an XY plane by taking an X axis of a space coordinate system of the three-dimensional model as a reference to obtain eight outer contour curves of the three-dimensional model;

setting the maximum slice thickness Z_maxAnd minimum slice thickness Z_min；

Slice thickness of the first layer above the starting plane is Z₁：Z₁Is a minimum slice thickness Z_min；

The second layer on the first layer has a slice thickness of Z₂: an outer contour curve in Z_minThe included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the second layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the slice thickness Z of the layer according to a slice thickness calculation formula₂；

The slice thickness of the third layer above the second layer is Z₃: an outer contour curve in Z₁+Z₂The included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the third layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the slice thickness Z of the layer according to a slice thickness calculation formula₃；

Similarly, the slice thickness of each layer is obtained;

the interpolation formula is: z is a radical of_n＝Z_min+(Z_max-Z_min)×|cosθ_n|(n＝1,2,……,8)；

SlicingThe thickness calculation formula is as follows:

3. the slicing method according to claim 2, wherein the step S2 is specifically: the three-dimensional model starts from the start plane, follows the slice thickness Z along the Z axis of the space coordinate system₁、Z₂、Z₃......Z_nAnd slicing to obtain the corresponding slice shape of each layer.

4. A printing method of a Delta mechanical arm-based photocuring 3D printer is characterized by comprising the following steps:

performing the slicing method of any one of claims 1 to 3;

obtaining corresponding exposure time T through the slice thickness and the parameters of the photosensitive resin, and calculating the exposure time T of each layer_i；

Adjusting the light source to the slice shape of the initial plane through a control circuit; moving Z by delta mechanical arm and Z-axis motor₁(ii) a Controlling the exposure time T of the light source by a control circuit₁Printing the first layer of slices;

adjusting the light source to a slice shape of the second layer by the control circuit; moving Z by delta mechanical arm and Z-axis motor₂(ii) a Controlling the exposure time T of the light source by a control circuit₂Printing the second layer of slices;

and sequentially printing each layer to obtain the three-dimensional model of the entity.

5. A printer characterized by using the printing method according to claim 4.

6. The printer of claim 5, comprising a delta robot, a Z-axis motor, a light source, a curing platform, a hopper, a control circuit; the Z-axis motor is arranged on the delta mechanical arm.

Technical Field

The invention relates to the field of 3D printing, in particular to a slicing method, a printing method and a printer of a light-curing 3D printer based on a Delta mechanical arm.

Background

At present, in a photocuring 3D printer, when a photosensitive material receives laser exposure with a certain frequency, the photosensitive material is converted from a liquid state to a solid state, and according to the characteristic, the photosensitive material is cured by layering in sequence from bottom to top, and finally, a required 3D model can be printed.

However, the accuracy of the printed 3D build is related to the maximum slice thickness Z of the printer_maxAnd minimum slice thickness Z_min(ii) related; when the thickness Z value of the slice selected for printing is larger, the printing efficiency is improved, but the precision of the 3D modeling is reduced; conversely, when the selected slice thickness Z value is small, the printing efficiency is reduced, but the accuracy of the 3D modeling is improved. In addition, the existing slicing mode for selecting the thickness of the fixed slice has obvious defects for printing variable-curvature curved surfaces and complex curved surface objects.

Disclosure of Invention

In order to solve the existing technical problems, the invention provides a slicing method, a printing method and a printer of a light-curing 3D printer based on a Delta mechanical arm, which can change the layering thickness according to the surface shape of the contour of an object so as to meet the requirement of the surface precision of the object.

The invention solves the technical problems in the prior art and provides a Delta mechanical arm-based photocuring 3D printer slicing method, which comprises the following steps: step S1, calculating the height of the three-dimensional model, extracting the outer contour of the three-dimensional model, and obtaining the number of slice layers and the slice thickness corresponding to the number according to the height data and the shape of the outer contour curve; and step S2, obtaining the slice shape of each layer according to the slice layer number and the slice thickness.

Further improvements of the invention are as follows.

Step S1 specifically includes: sectioning the three-dimensional model at intervals of 45 degrees in an XY plane by taking an X axis of a space coordinate system of the three-dimensional model as a reference to obtain eight outer contour curves of the three-dimensional model; setting the maximum slice thickness Z_maxAnd minimum slice thickness Z_min(ii) a Slice thickness of the first layer above the starting plane is Z₁：Z₁Is a minimum slice thickness Z_min(ii) a The second layer on the first layer has a slice thickness of Z₂: an outer contour curve in Z_minThe included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the second layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the slice thickness Z of the layer according to a slice thickness calculation formula₂(ii) a The slice thickness of the third layer above the second layer is Z₃: an outer contour curve in Z₁+Z₂The included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the third layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the slice thickness Z of the layer according to a slice thickness calculation formula₃(ii) a Similarly, the slice thickness of each layer is obtained; the interpolation formula is:

z_n＝Z_min+(Z_max-Z_min)×|cosθ_nl (═ 1,2, … …, 8); the slice thickness calculation formula is:

step S2 specifically includes: the three-dimensional model starts from the start plane, follows the slice thickness Z along the Z axis of the space coordinate system₁、Z₂、Z₃......Z_nAnd slicing to obtain the corresponding slice shape of each layer.

The invention solves the technical problems in the prior art and provides a printing method of a photocuring 3D printer based on a Delta mechanical arm, which comprises the following steps: carrying out the slicing method; obtaining corresponding exposure time T through the slice thickness and the parameters of the photosensitive resin, and calculating the exposure time T of each layer_i(ii) a Adjusting the light source to the slice shape of the initial plane through a control circuit; moving Z by delta mechanical arm and Z-axis motor₁(ii) a Controlling the exposure time T of the light source by a control circuit₁Printing the first layer of slices; adjusting the light source to a second by the control circuitSlice shape of the layer; moving Z by delta mechanical arm and Z-axis motor₂(ii) a Controlling the exposure time T of the light source by a control circuit₂Printing the second layer of slices; and printing to obtain the three-dimensional model of the entity.

The present invention solves the above-mentioned prior art problems and provides a printer using the above-mentioned printing method.

Further improvements of the invention are as follows.

The device comprises a delta mechanical arm, a Z-axis motor, a light source, a curing platform, a trough and a control circuit; the Z-axis motor is arranged on the delta mechanical arm.

Compared with the prior art, the invention has the beneficial effects that: the method has the advantages that the self-adaptive layering is adopted for selecting the layering thickness, namely, the layering thickness is changed according to the surface shape of the object outline in the Z-axis direction so as to meet the requirement of the surface precision of the object.

Drawings

FIG. 1 is a flowchart of a specific embodiment of the method for manufacturing a light-cured 3D printer based on a Delta mechanical arm.

Fig. 2 is a process diagram of fig. 1.

FIG. 3 is a schematic diagram of a three-dimensional model of an embodiment.

Fig. 4 is a graph of the eight outer contours of fig. 3.

Fig. 5 is a schematic slice view of fig. 3.

Fig. 6 is a schematic diagram of θ determined from the outer contour curve.

Detailed Description

The invention is further described with reference to the following description and embodiments in conjunction with the accompanying drawings.

As described in fig. 1-6.

A slicing method of a light-cured 3D printer based on a Delta mechanical arm comprises the following steps:

step S1, calculating the height of the three-dimensional model, extracting the outer contour of the three-dimensional model, and obtaining the number of slice layers and the slice thickness corresponding to the number according to the height data and the shape of the outer contour curve;

and step S2, obtaining the slice shape of each layer according to the slice layer number and the slice thickness.

In this slicing method, the three-dimensional model can be modeled using CAD software, and the three-dimensional model can also be modeled using three-dimensional drawing software existing in the art. After modeling, the height and the outer contour of the three-dimensional model can be extracted through the used three-dimensional drawing software, and the slice layer number and the slice thickness corresponding to the slice layer number are obtained on the basis of the height and the outer contour. Then, the slice shape corresponding to each layer is obtained based on the number of slice layers and the slice thickness corresponding to the number of slice layers.

Step S1 of the present invention specifically includes: sectioning the three-dimensional model at intervals of 45 degrees in an XY plane by taking an X axis of a space coordinate system of the three-dimensional model as a reference to obtain eight outer contour curves of the three-dimensional model; setting the maximum slice thickness Z_maxAnd minimum slice thickness Z_min(ii) a Slice thickness of the first layer above the starting plane is Z₁：Z₁Is a minimum slice thickness Z_min(ii) a The second layer on the first layer has a slice thickness of Z₂: an outer contour curve in Z_minThe included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the second layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the slice thickness Z of the layer according to a slice thickness calculation formula₂(ii) a The slice thickness of the third layer above the second layer is Z₃: an outer contour curve in Z₁+Z₂The included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the third layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the slice thickness Z of the layer according to a slice thickness calculation formula₃(ii) a Similarly, the slice thickness of each layer is obtained;

the interpolation formula is: z is a radical of_n＝Z_min+(Z_max-Z_min)×|cosθ_n|(n＝1,2,……,8)；

The slice thickness calculation formula is:

step S2 of the present invention specifically includes: the three-dimensional model starts from the start plane, follows the slice thickness Z along the Z axis of the space coordinate system₁、Z₂、Z₃......Z_nAnd slicing to obtain the corresponding slice shape of each layer.

By using the slicing method, the obtained slice thickness is based on the contour shape of the surface of the object, and when the contour curvature of the surface of the object is small, the slice thickness is relatively large; when the contour curvature of the surface of the object is larger, the slice thickness is relatively smaller, so that the printing modeling precision is higher compared with the traditional slice method.

The invention also provides a printing method of the photocuring 3D printer based on the Delta mechanical arm, which comprises the following steps: first, the above-described slicing method is performed; then obtaining corresponding exposure time T through the slice thickness and the parameters of the photosensitive resin, and calculating the exposure time T of each layer_i(ii) a Adjusting the light source to the slice shape of the initial plane through a control circuit; moving Z by delta mechanical arm and Z-axis motor₁(ii) a Controlling the exposure time T of the light source by a control circuit₁Printing the first layer of slices; adjusting the light source to a slice shape of the second layer by the control circuit; moving Z by delta mechanical arm and Z-axis motor₂(ii) a Controlling the exposure time T of the light source by a control circuit₂Printing the second layer of slices; and similarly, printing each layer to finally obtain the three-dimensional model of the entity.

The invention also provides a printer and a printing method using the printer. The printer comprises a delta mechanical arm, a Z-axis motor, a light source, a curing platform, a trough, a control circuit and other parts; the Z-axis motor is arranged on the delta mechanical arm. Meanwhile, the printer also comprises an outer contour extraction module, an automatic slicing module and a processing file generation module; the step 1 is implemented by an outer contour extraction module, the step 2 is implemented by an automatic slicing module, and the printing step is completed by controlling a delta mechanical arm, a Z-axis motor and a light source by a processing file generation module.

The method of the present invention provides a printing embodiment comprising the steps of:

and modeling the three-dimensional model by using three-dimensional drawing software, and exporting an Igs format file or a step format file of the three-dimensional model.

And importing the Igs format file or the step format file into AutoCAD software, setting the Z axis as a default printing direction, adjusting the printing direction required by the model to be parallel to the Z axis in a Cartesian coordinate system, and simultaneously adjusting the center of the model to be coincided with the origin.

And loading the outline extraction module and the automatic slicing module through a netload command of AutoCAD. The loading module may call a special command self-made inside the module.

Selecting the three-dimensional model by calling a setting parameter command of the outer contour extraction module, obtaining the model height of the three-dimensional model and setting the minimum slice thickness Z_minAnd maximum slice thickness Z_max,In this example, the height of the model is 10.87mm and the minimum slice thickness Z_minSet to 0.03mm, maximum slice thickness Z_maxSet at 0.1 mm.

And cutting every 45 degrees in an XY plane by calling a slice thickness calculation command of the outer contour extraction module with the X axis of a three-dimensional model space coordinate system as a reference to obtain eight outer contour surface areas of the three-dimensional model, and obtaining eight outer contour curves of the three-dimensional model by using an explosion command.

Slice thickness of the first layer above the starting plane is Z₁：Z₁Is a minimum slice thickness Z_min(ii) a The second layer on the first layer has a slice thickness of Z₂: an outer contour curve in Z_minThe included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the second layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the slice thickness Z of the layer according to a slice thickness calculation formula₂(ii) a The slice thickness of the third layer above the second layer is Z₃: an outer contour curve in Z₁+Z₂The included angle between the tangent of the height point and the Z axis is theta according to theta and Z_maxAnd Z_minThe slice thickness component z of the third layer of the outer contour curve is calculated by interpolation_n(ii) a Obtaining the layer according to a slice thickness calculation formulaSlice thickness Z₃(ii) a Similarly, the slice thickness of each layer is obtained;

the interpolation formula is: z is a radical of_n＝Z_min+(Z_max-Z_min)×|cosθ_n|(n＝1,2,……,8)；

The slice thickness calculation formula is:

the method comprises the steps of creating a sectioning plane parallel to an XY plane by calling an automatic sectioning command of an automatic sectioning module, calling a built-in sectioning command to obtain a section shape with a corresponding height, calling a built-in visual angle adjusting command to adjust to a top view visual angle, and calling a built-in bitmap exporting command to export a bitmap file of the section shape with the height. The operations are circulated until the tail part of the array, the bitmap file of the three-dimensional model with different slice shapes can be obtained, and the fact that the slice thickness at the bottom is small, the step effect is not obvious, the slice thickness at the top is large can be found, and the 3D processing efficiency can be improved.

Calling a processing file generation module through labview, calculating exposure time according to the slice thickness and parameters of photosensitive resin, finishing the exposure time of all slices, binding the exposure time, the slice thickness and the bitmap files of the slices according to the sequence from bottom to top, and then sequencing.

Adjusting the light source to be consistent with the slice shape of the printed layer by the control circuit; moving the corresponding slice thickness through a delta mechanical arm and a Z-axis motor; the exposure time of the light source is controlled by a control circuit. And finishing a slicing printing action at the moment, and sequentially printing from bottom to top according to the data in the processed file to obtain the three-dimensional model.

The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.