1. Principle – more than 3D Printing but Additive Manufacturing Primary questions:  How can be one solid layer formed?  How can two layers be adhered? Process requirement (functional): FR1: create one solid layer. FR2: glue two consecutive layers in the deposit direction (z-axis). x y z

2. Principle – more than 3D Printing but Additive Manufacturing Process principle for FR1 (make one layer of solids): Powder Liquid Sheet Powder Air Solid Powder-based Liquid-based Sheet-based Opportunity of innovation  Frost  Snow

3. For the liquid state of a certain material X, the freezing effect can allow the liquid to solidify. That is, to drop cold droplet on the liquid material, and the liquid solidifies to a solid. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry X is not every kind of material but a restricted set of materials Process principle for FR1 (make one layer of solids):

4. For the liquid state of a certain material X, photo-resistive to UV light, can allow the liquid to solidify. That is, to have a mask such that the materials exposed to UV light will remain as a solid. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry X is not every kind of material but a restricted set of materials Process principle for FR1 (make one layer of solids):

5. For the powder state of a certain material Y, there is a physical principle called heat-fusion to bind two particles. However, not all materials are heat-fusible. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Y is not every kind of material but a restricted set of materials Process principle for FR1 (make one layer of solids):

6. For the powder state of a certain material Y, there is a physical principle which is like welding with fillers to bind two particles. That is, a bond materials are shot on the layer of the material., and the powers glue to solid. However, not all materials are bondable in this way. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Y is not every kind of material but a restricted set of materials Process principle for FR1 (make one layer of solids):

7. For the sheet state of a certain material Z, there is a physical principle the sheet is cut by an energy beam such as laser. As such, a solid can be formed, and then another layer of sheet. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Z is not every kind of material but a restricted set of materials Process principle for FR1 (make one layer of solids):

8. For the liquid state of a certain material W, it solidifies when it is put in an environment with the temperature being sufficiently lower than the melting point of the material W, and then W turns to a solid. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry W is not every kind of material but a restricted set of materials 3D Printing Process principle for FR1 (make one layer of solids):

9. Principle – more than 3D Printing but Additive Manufacturing Powder Liquid Sheet Powder Air Solid Powder-based Liquid-based Sheet-based Opportunity of innovation  Frost  Snow Process principle for FR2 (glue two layers of materials):

10. The principle to glue the two layers is the photosensitive effect - i.e., the gluing of the upper layer of liquid to the previous solid layer is completed during the solidification of the upper layer of liquid. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Liquid Solid Liquid Solid Process principle for FR2 (glue two layers of solids):

11. The glue of the liquid layer to the previous solid layer is completed during the solidification process of the upper liquid layer based on the droplet freezing effect. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Liquid Solid Liquid Solid Process principle for FR2 (glue two layers of solids):

12. The principle to glue to layers of the solid is the photo-sensitive effect, that is, during the solidification process of the upper liquid layer, it glues with the previous layer of the solid. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Liquid Solid Liquid Solid Process principle for FR2 (glue two layers of solids):

13. The glue of the upper layer of powers to the previous layer of solid is based on the heat-fusion effect. The process is very much like the welding process. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Powder Solid Powder Solid Process principle for FR2 (glue two layers of solids):

14. The gluing of the upper layer of powder to the previous solid layer is based on the effect of bonding material in the powder. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Powder Solid Powder Solid Process principle for FR2 (glue two layers of solids):

15. The gluing of the upper layer of the sheet to the previous layer of sheet is through adhesion on the back of the sheet. Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry Sheet Solid Sheet Solid Process principle for FR2 (glue two layers of solids):

16. The gluing of the upper layer of the liquid (molten material) to the previous solid layer is completed during the process of material fusion Principle – more than 3D Printing but Additive Manufacturing Principle ??? Sheet Liquid Powder Solids Physics, Chemistry, Biology or their combination such as bio-physics, bio- chemistry, physics-chemistry 3D Printing or FDM Liquid Solid Liquid Solid Process principle for FR2 (glue two layers of solids):

17. Principle – more than 3D Printing but Additive Manufacturing Rectification for 3D Printing (in terms of the principle):  3D Printing is a kind of additive manufacturing technology.  The principle of 3D printing is molten material will solidify quickly in a sufficient low temperature environment.  3D printing directly dispenses molten materials to the object (an initial platform or solid layer of the materials).  3D printing glues two layers of the materials (a previous solid layer and a layer of liquid in the process of solidification) based on the heat-fusion.  3D printing = Fused Deposition Modeling (FDM) = Fused Filament Fabrication (FFF) = RP (rapid prototyping).

18. Analysis: Pros and Cons Pros of additive manufacturing technology: 1.No need of tooling for making a product, thus most suitable for concept design and marketing. 2.Capable of making complex internal features, thus most suitable for tissue engineering. 3.Highly customization, thus most suitable to tissue engineering. 4.Rapid production compared with those that need tooling. 5.Low cost in production compared with those that need tooling. 6.Large design space due to its capability of making complex shape products. 7.High sustainability.

19. Analysis: Pros and Cons Cons of additive manufacturing technology: 1.Poor mechanical property: strength and stiffness. 2.Poor accuracy. 3.Need of post-processing in order to make products more functional. 4.Polymer materials.

20. Analysis: Pros and Cons Pros and cons of 3D printing among all the additive manufacturing technologies: 1.Cons: Limited scope of materials that can be used: ABS, PLA. 2.Cons: Poor strength (tension) and stiffness. 3.Pros: simple equipment (due to the principle). 4.Pros: simple maintenance.

21. 3D Bio-plotter  It is 3D printer with special types of materials, that is, biomaterials.  Cleaning for bio-cells.

22. 3D printing system 3D Printing overall function Heat materials to the molten state Dispense the molten material Glue two consecutive layers of the material Supply materials Feed materials Heat materials Move in the x-axis Move in the y-axis Move in the z-axis

23. 3D printing system The six devices fulfill the six functions as mentioned in the preceding slide

24. Future  Feeding the filament more effectively.  Heating the filament of metals, ceramics.  Retracting the molten materials.  6D degrees of freedom (DOF) relative motion between the nozzle and platform.  Scaffolding and seeding simultaneously.  Bio-inspired tissue reconstruction.  Rational design and control of scaffold for support and drug release.

25. Future  6D degrees of freedom (DOF) relative motion between the nozzle and platform

26. Future  6D degrees of freedom (DOF) relative motion between the nozzle and platform

27. Future  Scaffolding and seeding simultaneously

28. Future  Bio-inspired tissue reconstruction Stem cells and active cells Scaffold for support and nutrition release Incubator Biological true tissue Direct bio-engineering replacement human tissues on-demand for transplantation.

29. Future  Rational design and control of scaffolds On demand tissue repair (chemical and physical requirements of individual patients)  Design scaffolds  Seed cells  Supply foods  Stimulate cells  Scaffold degradation control  Food supply adjustment  Cell stimulation adjustment

30. Concluding Remarks Corrigendum and Position Statement: revisit 3D Printing is not the everything of manufacturing technology but a manufacturing technology that is  of universal capability in terms of making the shape of product,  agile in terms of readiness of accessibility and availability, and  Suitable to one-kind-of-production (OKP). Add:  3D Printing is one of the additive manufacturing technologies.  Fused deposition principle, leading to simple equipment set up.  It is most promising in bio manufacturing, including design, fabrication and control.

31. End and thank you Question & comment ?