What is the Next Frontier in 3D Printing?

During its early days, 3D printing (also known as additive manufacturing) was mainly considered a rapid prototyping process. It provided people a convenient way to prototype complex shapes. Over the last twenty years, the popularity of 3D printing has grown tremendously and it is now being used in a wide variety of applications. Here is a representative list:

Production Parts: People are now making production parts using 3D printing. It enables production of complex custom shapes without requiring specialized tooling. This offers designers a much wider variety of shapes and significantly cuts down the lead time. Geometric shape flexibility afforded by 3D printing can be used to reduce weight and reduce the part count in the product. Famous examples of this category include fuel nozzles in engines and custom hearing aids.

3D Printed Fuel Nozzle for Engine (Image Source https://gereports.ca/slideshow/look-ahead-master-class-advanced-aviation/)

Example of a 3D Printed Hearing Aid (Image Source: https://audicus.com/hearing-aids-3d-printing/)

Biologically Inspired Robots: 3D printing enables manufacturing of biologically inspired robots that have complex shapes and mechanisms to realize biologically inspired locomotion and manipulation.

R2G2: A 3D Printed Robot Developed by My Student James Hopkins that Uses a High Speed Rectilinear Gait

Cars: 3D printing is being used to fabricate the body and structural members of the custom cars. 

Local Motors 3D Printed a Car (Image Source:
http://www.popularmechanics.com/cars/a16726/local-motors-strati-roadster-test-drive/)

Prosthesis: 3D printing has been used to create hand prosthesis because of its ability to offer custom designs to fit the patient's size and needs. 

Examples of 3D Printed Hand Prosthesis (Image Source: http://enablingthefuture.org/upper-limb-prosthetics/raptor-reloaded/)

Molds and Dies: It used to take months to make molds and dies used in popular mass production processes such as injection molding and die casting. The use of 3D printing has reduced the mold making time to few days. 3D printing is able to incorporate internal features in the molds that significantly improve cooling time and hence improve the performance of the molding process. 

Example of 3D Printed Insert for Injection Mold (Image Source: http://www.eos.info/press/customer_case_studies/fwb)

Chocolates: 3D printing is now being used to produce custom chocolates. There are many other products in the food sector that are being considered as potential candidates for 3D printing. 3D printing can faithfully reproduce complex intricate shapes and offer novel food textures. 

A Chocolate Printed on ChefJet Pro Printer (Image Source: http://www.3dsystems.com/)

Biological Organs: Technologies inspired by 3D printing are being explored to create biological organs such as kidneys and ears. 

3D Printed Ear that Fuses Biological and Electronic Parts (Image Source: http://www.nature.com/news/the-printed-organs-coming-to-a-body-near-you-1.17320)

Drugs: 3D printing can be used to produce fast dissolving drugs to speed up absorption in the body.

Example of a Fast Dissolving Drug from Aprecia Pharmaceuticals (Image Source: https://www.aprecia.com/)

Buildings: Large 3D printers are being built that can print entire buildings.

A Large 3D Printer for Printing Buildings (Image Source: http://www.wasproject.it/w/en/)

Sculptures: Artists have also embraced 3D printing. They can use it to make new sculptures quickly and explore shapes that would have been almost impossible to sculpt manually. General public can also use 3D printing to print copies of famous sculptures at home.

Example of a 3D Printed Sculpture (Image Source: http://airwolf3d.com/)

Education: The uses of physical models can be of tremendous help in explaining complex concepts in geometry, molecular structures in chemistry and biology. 3D printing is being used to create physical models to enrich the educational experience. 

3D Printed Models to Explain Geodesic Spheres (Image Source: http://www.shapeways.com/)

Entertainment and Recreation: This industry is also utilizing 3D printing to innovate and pursue new creative avenues. Marketplaces are emerging to enable people to buy and sell 3D printed toys.

Example of a Toy that can be 3D Printed (Image Source: http://www.shapeways.com/superfanart/mylittlepony)

Clothing: Visionary designers are creating 3D printed clothes. This is not yet a mainstream trend. However, as wearable technologies get integrated into clothes, 3D printed clothes might start gaining momentum.

Example of Dress Created by Michael Schmidt Studio (Image Source: http://www.michaelschmidtstudios.com/dita-von-teese.html)

Jewelry: 3D printing is well suited for making custom jewelry and gaining popularity in the jewelry industry. 

Example of 3D Printed Jewelry from Artizan Work (Image Source: http://www.artizanwork.com/)

What is the next frontier in 3D printing? Here are my thoughts:

• The current generation of 3D printing technologies has focused on offering flexibility in geometry. The next generation 3D printers are expected to offer many more choices in material. Once we have the freedom to select the material of our choice, the design space will expand and we should be able to realize novel products.
• Setting up traditional manufacturing factory in space will be hard. 3D printing will be an attractive option for manufacturing in space or other planets.
• A 3D printer that can replicate itself will revolutionize manufacturing.

I am interested in hearing your thoughts about the next frontier in 3D printing.

Societal Implications of Advanced Manufacturing

What distinguishes humans from other living creatures is their ability to (1) grow food for providing nourishment, (2) alter the surrounding environment (e.g., construct buildings, bridges, roads etc.) to facilitate modern living, and (3) manufacture artifacts to improve the quality of life. 

The importance of being self-reliant on food production is well understood by every nation. For example, the US produces a large portion of food items consumed by its population. Construction by its very nature takes place in the communities that are going to benefit from it. Manufacturing on the other hand has seen large geographical shifts due to economic considerations. This has major societal implications.   

As countries around the world experience high unemployment rates and large trade deficits, there appears to be a vibrant debate about the role of manufacturing in the society. Developed nations are primarily interested in high value manufacturing that creates high paying jobs and export opportunities for its manufacturers. This type of manufacturing is often called Advanced Manufacturing. A number of enabling technologies are having a profound effect on the manufacturing sector. This post explores the value of Advanced Manufacturing in the societal context.

I have categorized advanced manufacturing into four main areas and tried to list challenges, enabling technologies, goals,  and societal implications for them. 

1. Smart Manufacturing

• Challenges: Manufacturing consumes significant resources and negatively impacts the environment. To compete favorably, companies need to offer high quality products of increasing complexity at a faster pace with lower prices.  
• Enabling Technologies for Addressing These Challenges: Internet of Things, Low Cost Sensors, Ubiquitous Computing, Machine Learning, and Cloud Computing
• Goal: Improve manufacturing efficiency and productivity
• Societal Implications:  Reduce environmental impact of manufacturing, create high paying jobs in manufacturing, and reduce cost 

2. Automation

• Challenge: Manufacturing involves significant manual labor and hence not competitive in high wage regions  
• Enabling Technologies for Addressing This Challenge: Digital Models, Virtual Prototyping Software, Human-Friendly Robots, Human Robot Collaboration, and Automated Material Handling Systems  
• Goal: Reduce human labor in manufacturing 
• Societal Implications: Make domestic production viable, increase exports, and enhance national security by reducing reliance on imported goods

3. Advanced Materials 

• Challenge: Existing materials limit the design options
• Enabling Technologies for Addressing This Challenge: Advances in Nanotechnology, Biotechnology, and Composites  
• Goal: Develop new materials to overcome functional limitations of existing materials
• Societal Implications: Enable invention and creation of new products    

4. Process Innovations

• Challenge: Existing processes impose constraints on what can be made
• Enabling Technologies for Addressing This Challenge: 3D Printing, Additive Manufacturing, In-Mold Assembly, Microfabrication, and Nanofabrication
• Goal: Develop new processes to overcome limitations of existing processes
• Societal Implications: Democratize manufacturing, empower innovators, reduce barriers to create new businesses based on new products  

I would like to hear your thoughts.

3D Printing: Hype or New Manufacturing Revolution?

Lately 3D printing has been in news a lot. People are talking about using 3D printing to fabricate a wide variety of artifacts including shoes, robots, drones, cupcakes, and kidneys. Is this just hype or a new manufacturing revolution? To answer this question let us review the desired characteristics in a manufacturing process. My personal wish list includes the following:

1. No lead time
2. No part-specific tooling
3. No specialized expertise needed to run the processing equipment
4. No setup time
5. Low processing time (laws of physics prohibit wishing for zero processing time!)
6. Low material cost
7. Low equipment cost
8. Low operation cost
9. Ability to realize arbitrarily complex shapes
10. Ability to process any material
11. High accuracy
12. No negative environmental impact

Now let us examine how 3D printing fares with respect to my wish list. 3D printing does not require any part specific tooling, complex process planning, or elaborate setup step. Instructions for driving 3D printers can be automatically generated from 3D CAD models in matters of seconds. Using most 3D printers does not require any specialized skills. Fabrication can begin within few minutes after getting the 3D model. So 3D printing looks very attractive in terms of items #1 through #4 in the list above.

3D printing is a slow process. So printing a large part takes a long time. Forming and consolidation processes such as stamping, molding, and casting are much faster in terms of processing time for making large parts. But for making small parts, 3D printing appears to be quite competitive because overall processing times are small. 3D printing is also quite attractive in terms of processing time for making large intricate parts in comparison to subtractive processes such as milling. For such parts, subtractive processes tend to be slow because they need to remove a large volume of material to create the final part shape.

Currently, many 3D printers use proprietary materials. So the material cost tends to be high. However, this is not an inherent limitation of 3D printing. As more companies compete in this space, the economy of scale should bring the material cost down.

Open source designs of 3D printers have led to a drastic reduction in prices for certain types of 3D printers. Currently there are 3D printers in the market that cost less than $1000. This development has made this technology accessible to a wide variety of users. High-end 3D printers are still very expensive. There are significant opportunities for developing low cost 3D printers that work with metals and high strength polymer materials.

The processing cost is a function of human labor cost, equipment cost, hourly operation cost and processing time. As discussed earlier, 3D printing does not require much human labor. Open source movement is bringing down the equipment cost. So the energy cost is the main component of the hourly operation cost. 3D printer power consumption is comparable to other manufacturing processes. So the main driver for the processing cost is processing time. As discussed earlier, 3D printing is a slow process. Therefore, processing costs tend to be high for making large parts. Most 3D printers require post-processing operations to clean parts. This step leads to additional costs.

3D printers are able to fabricate very complex shapes. Moreover, the increased geometric complexity of the part does not lead to increased cost in the world of 3D printing. This encourages use of parts with intricate internal cavities to enhance performance and reduce weight. The reduction in the amount of material used in the part also helps in realizing more sustainable products by minimizing the material use. However, designing geometrically complex parts manually using the current CAD systems is a very tedious and error prone task. So we will need to develop automated shape synthesis tools that can automatically create new shapes from the functional requirements to fully exploit the capabilities of the 3D printing technology.

Currently 3D printers offer limited material choices. In fact, most 3D printers only work with low grade plastics. There are few printers in the market that work with a selected number of metals. Increasingly, composites are being used in a wide range of products including aircrafts and automobiles because of their high strength, light weight, and corrosion resistance. The next generation 3D printers will need to be able to process polymer composites and a richer variety of metals.

3D printing is a process in which a part is build layer-by-layer. So layer thickness determines the part accuracy. It is possible to achieve reasonably high accuracy using 3D printing by using very small layer thickness. But this leads to high processing time and high processing costs.

Many different types of 3D printing processes exist with different levels of environmental impact. There exist 3D printing processes that have virtually no negative environment impact except the energy consumption. So clearly, eco-friendly 3D printers are possible. However, reducing the energy consumption will require significant further development in this area.

3D printing is expected to be useful both for in-home manufacturing and factory production. In fact 3D printing can be used to make tooling (e.g., mold and patterns) for traditional processes. It has already enabled e-commerce in the manufacturing sector. Designers are able to buy 3D printed parts over the Internet.

Facilitating the increased in-home use of this technology will require making this technology much more user-friendly. CAD systems are often used to create 3D models to be printed on 3D printers. People with limited technical expertise find CAD systems hard to use. CAD system user interface has to improve significantly in terms of user friendliness for a lay person to effectively utilize 3D printers for in-home use. The improved interfaces will enable the use of 3D printing in K-12 schools. It will also enable people with limited technical background to participate in the invention process.

So in summary, 3D printing has many desirable characteristics. It meets many unfilled needs in the market. So it is here to stay!

But let us remember that 3D printing is not a perfect process. In my opinion, 3D printing is a precursor to a new manufacturing revolution. Let us take inspiration from it and continue to look for a process that has all the desirable characteristics in the wish list presented above!