设计师, 制造商, 和其他人经常使用 3D 打印来快速制作一系列功能对象, 的原型，从电影道具到医疗设备。准确的打印预览至关重要，这样用户才能知道制造的物体将按预期运行。
Designers, makers, and others often use 3D printing to rapidly prototype a range of functional objects, from movie props to medical devices. Accurate print previews are essential so users know a fabricated object will perform as expected.
但大多数 3D 打印软件生成的预览注重功能而不是美观。打印的对象最终可能会出现与用户预期,不同的颜色,纹理,或阴影，从而导致多次重印，浪费时间,精力,和材料。
But previews generated by most 3D-printing software focus on function rather than aesthetics. A printed object may end up with a different color, texture, or shading than the user expected, resulting in multiple reprints that waste time, effort, and material.
为了帮助用户想象制造的物体的外观,，来自麻省理工学院和其他地方的研究人员开发了一种易于使用的预览工具，该工具将外观放在首位。
To help users envision how a fabricated object will look, researchers from MIT and elsewhere developed an easy-to-use preview tool that puts appearance first.
用户从 3D 打印软件, 上传该物体的屏幕截图以及打印材料的单个图像。根据这些输入,，系统会自动生成所制造的物体可能的外观的渲染图。
Users upload a screenshot of the object from their 3D-printing software, along with a single image of the print material. From these inputs, the system automatically generates a rendering of how the fabricated object is likely to look.
名为 VisiPrint, 的人工智能驱动系统, 旨在与一系列 3D 打印软件配合使用，并且可以处理任何材料示例。它不仅考虑了材料, 的颜色，还考虑了光泽度, 半透明度, 以及制造过程的细微差别如何影响对象的 的外观。
The artificial intelligence-powered system, called VisiPrint, is designed to work with a range of 3D-printing software and can handle any material example. It considers not only the color of the material, but also gloss, translucency, and how nuances of the fabrication process affect the object的 appearance.
这种以美学为中心的预览在牙科,等领域特别有用，可以帮助临床医生确保临时牙冠和牙桥与患者的牙齿,的外观相匹配，或者在建筑,中帮助设计师评估模型的视觉影响。
Such aesthetics-focused previews could be especially useful in areas like dentistry, by helping clinicians ensure temporary crowns and bridges match the appearance of a patient的 teeth, or in architecture, to aid designers in assessing the visual impact of models.
“3D 打印可能是一个非常浪费的过程。一些研究估计，多达三分之一的材料直接进入垃圾填埋场,，通常来自用户最终丢弃的原型。为了使 3D 打印更具可持续性,，我们希望减少获得您想要的原型所需的尝试次数。用户不应该’t 在决定设计之前必须尝试他们拥有的每种打印材料,” 电气工程和计算机科学 (EECS) 研究生和 VisiPrint 论文的主要作者 Maxine Perroni-Scharf, 说。
“3D printing can be a very wasteful process. Some studies estimate that as much as a third of the material used goes straight to the landfill, often from prototypes the user ends of discarding. To make 3D printing more sustainable, we want to reduce the number of tries it takes to get the prototype you want. The user shouldn’t have to try out every printing material they have before they settle on a design,” says Maxine Perroni-Scharf, an electrical engineering and computer science (EECS) graduate student and lead author of a paper on VisiPrint.
研究人员重点研究了最常见的 3D 打印类型 (FDM), 熔融沉积建模。在 FDM, 中，打印材料丝被熔化，然后通过喷嘴喷射，一次一层地制造物体。
The researchers focused on fused deposition modeling (FDM), the most common type of 3D printing. In FDM, print material filament is melted and then squirted through a nozzle to fabricate an object one layer at a time.
生成准确的美学预览具有挑战性，因为熔化和挤出过程可能会改变材料的外观,，每个沉积层的高度以及制造过程中喷嘴遵循的路径也会改变。
Generating accurate aesthetic previews is challenging because the melting and extrusion process can change the appearance of a material, as can the height of each deposited layer and the path the nozzle follows during fabrication.
VisiPrint 使用两种人工智能模型共同克服这些挑战。
VisiPrint uses two AI models that work together to overcome those challenges.
VisiPrint 预览基于两个输入:、来自用户的 3D 打印软件(（称为“slicer” 软件),）的数字设计屏幕截图和打印材料的图像,，该图像可以从在线来源获取或从打印样本中捕获。
The VisiPrint preview is based on two inputs: a screenshot of the digital design from a user的 3D-printing software (called “slicer” software), and an image of the print material, which can be taken from an online source or captured from a printed sample.
根据这些输入,，计算机视觉模型从材料样本中提取对对象的 外观很重要的特征。
From these inputs, a computer vision model extracts features from the material sample that are important for the object的 appearance.
它将这些特征输入到生成 AI 模型中，该模型计算对象, 的几何形状和结构，同时合并所谓的 “slicing” 图案，喷嘴在挤出每一层时将遵循该图案。
It feeds those features to a generative AI model that computes the geometry and structure of the object, while incorporating the so-called “slicing” pattern the nozzle will follow as it extrudes each layer.
研究人员’方法的关键是特殊的调理方法。这涉及仔细调整模型的内部工作原理以引导它,，使其遵循切片图案并遵守 3D 打印过程的约束。
The key to the researchers approach is a special conditioning method. This involves carefully adjusting the inner workings of the model to guide it, so it follows the slicing pattern and obeys the constraints of the 3D-printing process.
他们的调节方法利用深度图来保留对象,的形状和阴影，以及反映内部轮廓和结构边界的边缘图。
Their conditioning method utilizes a depth map that preserves the shape and shading of the object, along with a map of the edges that reflects the internal contours and structural boundaries.
“如果你没有’t在这两件事上取得正确的平衡,你可能会用坏的几何形状或不正确的切片图案。我们必须小心翼翼地以正确的方式组合它们,” Perroni-Scharf 说。
“If you don’t have the right balance of these two things, you could use up with bad geometry or an incorrect slicing pattern. We had to be careful to combine them in the right way,” Perroni-Scharf says.
该团队还制作了一个易于使用的界面，可以上传所需的图像并评估预览。
The team also produced an easy-to-use interface where one can upload the required images and evaluate the preview.
VisiPrint 界面使更先进的制造商能够调整多个设置,，例如某些颜色对最终外观的影响。
The VisiPrint interface enables more advanced makers to adjust multiple settings, such as the influence of certain colors on the final appearance.
最后, 美观预览旨在补充切片软件, 生成的功能预览，因为VisiPrint 不会估计可打印性, 机械可行性, 或失败的可能性。
In the end, the aesthetic preview is intended to complement the functional preview generated by slicer software, since VisiPrint does not estimate printability, mechanical feasibility, or likelihood of failure.
为了评估 VisiPrint,，研究人员进行了一项用户研究，要求参与者将该系统与其他方法进行比较。几乎所有参与者都表示，它提供了更好的整体外观以及与印刷物体更多的纹理相似性。
To evaluate VisiPrint, the researchers conducted a user study that asked participants to compare the system to other approaches. Nearly all participants said it provided better overall appearance as well as more textural similarity with printed objects.
此外, VisiPrint 预览过程平均需要大约一分钟,，比任何竞争方法快两倍多。
In addition, the VisiPrint preview process took about a minute on average, which was more than twice as fast as any competing method.
“VisiPrint 与其他 AI 界面相比确实很出色。如果你给一个更通用的人工智能模型相同的屏幕截图,，它可能会随机改变形状或使用错误的切片模式，因为它没有直接调节,”，她说。
“VisiPrint really shined when compared to other AI interfaces. If you give a more general AI model the same screenshots, it might randomly change the shape or use the wrong slicing pattern because it had no direct conditioning,” she says.
在未来,，研究人员希望解决模型预览具有极其精细的细节时可能出现的伪影问题。他们还希望添加一些功能，使用户能够优化材料颜色之外的部分打印过程。
In the future, the researchers want to address artifacts that can occur when model previews have extremely fine details. They also want to add features that allow users to optimize parts of the printing process beyond color of the material.
“思考我们制造物体的方式很重要。我们需要继续努力开发减少浪费的方法。为此,人工智能与物理制作过程的结合是未来工作的一个令人兴奋的领域,” Perroni-Scharf说。
“It is important to think about the way that we fabricate objects. We need to continue striving to develop methods that reduce waste. To that end, this marriage of AI with the physical making process is an exciting area of future work,” Perroni-Scharf says.
“‘所见即所得 是 20 世纪 80 年代桌面出版‘发生的主要因素,，因为它允许用户在第一次尝试时就得到他们想要的东西。现在也是采用所见即所得的 3D 打印方式的时候了。 VisiPrint 是朝着这个方向迈出的一大步,” 哈索·普拉特纳研究所, 的计算机科学教授 Patrick Baudisch, 说，他没有参与这项工作。
“‘What you see is what you get has been the main thing that made desktop publishing ‘happen in the 1980s, as it allowed users to get what they wanted at first try. It is time to get WYSIWYG for 3D printing as well. VisiPrint is a great step in this direction,” says Patrick Baudisch, a professor of computer science at the Hasso Plattner Institute, who was not involved with this work.
这项研究的,部分,由麻省理工学院晨兴设计学院奖学金和麻省理工学院MathWorks奖学金资助。
This research was funded, in part, by an MIT Morningside Academy for Design Fellowship and an MIT MathWorks Fellowship.