3D Printer with multi material Pneumatic extruder

Project Title

3D Printer with multi material Pneumatic extruder

Project Area of Specialization 3D/4D PrintingProject Summary

3D printing has evolved into a powerful field that is rapidly revolutionizing manufacturing processes. Many industries, including mechanical, electrical, biomedical, and aerospace, employ 3D printing to improve design manufacturing and reduce lead time and tooling costs for new things manufactured. Traditional machining methods such as turning, milling, and drilling were used to help humans make items many decades ago. However, they are no longer as widely employed as they once were due to several limits and restraints, such as the high cost of production procedures. In this regard, the concept of 3d printing has been introduced.

The goal of this project is to create a Pneumatic Extrusion Module (PEM) that can dispense viscous materials to control using a digital pneumatic valve. It is also known as additive manufacturing, which is part of rapid prototyping in which it is possible to form 3-dimensional objects from a digital file. Commonly used additive manufacturing systems typically include a single extrusion module based on Fused Filament Fabrication (FFF), and its processing software generates G-code for this FFF module based on process parameters. PEM's functioning is managed by an Arduino, which connects with standard G-Code for 3D printing in real time. Different processing modules, such as viscous extruders and Direct Ink Writing, are not supported by these systems and software.

Our project is focused on the development of a pneumatic extruder that is capable of dispensing viscous materials such as polymers, high-performance polymers, conductive materials, and UV raisins through a pneumatic controller. The pneumatic controller includes a pneumatic valve which will be connected with an air compressor and an integrated circuit that will control the pressure of the material. The circuit will be then connected to the Arduino microcontroller attached to a 3D printer and will communicate with the traditional G-code for 3D printing in real time. The structure of the integrated circuit will be designed by us. The modeling process needs to be taken extra care to ensure that the extruder can operate without clogging and leaking. The simulation tool for polymer composite extrusion should be capable of handling critical components of the process. Parameters like viscosity, fluid flow, fluid density is taken into account while modeling the extruder.

Project Objectives

According to the surveys done over the period of last 10 years, the most common challenge faced during 3D printing is the limitation of material. Secondly, previous extruders like syringe pumps and others were unable to provide precise results and cause dimensional errors. The reason behind the limitation and precision is the viscosities of the materials. Extruders like syringe pumps get clogged if a material of high viscosity is used and if the viscosity is too low it causes leakage.

The solution to these problems is to design an extruder that can extrude multiple materials of various viscosity. A Pneumatic extruder attached to a 3D Printer would help us to deal with the materials of different viscosities. It eliminates these issues, making the 3D printer more efficient and versatile. The extruder would also be portable so we can use it with other 3D printers too. Materials such as polymers, conductive material, resistive material, UV curable resins and others can be used.

Project Implementation Method

A common 3D-printer requires a lot of steps on the backend before printing. Firstly, a CAD design is made on any cad software such as Solidworks which creates an stl file of the final product. Next, the stl file is uploaded to a slicing software such as Ultimaker Cura which slices the final product into sequential layers and a G-code is created which is uploaded into the printer using a SD card.The 3D printer then moves according to the G-code provided by the SD card and extrudes material from the nozzles to print a 3D model.

The pneumatic extruder works on a pressure based model, where the solenoid valve is used to control the in and outflow of air. When the solenoid valve is turned on, the system switches from PLA to pneumatic extruder. Air from the air compressor goes through the valve which is then fed to the syringe containing the material. The pressure is regulated by the pressure gauge attached to the system to ensure proper and uniform extrusion of the liquid material.

Benefits of the Project

Pneumatic extruder can be used to print multi material products which have a great scope in industries. Additive manufacturing is an intelligent manufacturing technology that can quickly build a variety of complex objects with single or different functional materials. If this technology can be used to print mechanical structures with sensing or electronic features, it will be able to break through the development bottleneck of a smart gripper and achieve the goal of rapid industrial development.

We can use a pneumatic extruder to print a sandwich pad with soft and hard material structure, including double-layer material pad and three-layer material pad which will be a finer printing performance than a traditional FDM machine. Moreover, our pneumatic extruder will be portable which will allow industries to only attach an extra extruder instead of buying a whole separate 3D-printer and since it’s compatible with marlin software which is open source, no additional equipment is required.

Using multilaterals, it is possible to make Piezoelectric Sensing Pads using a pneumatic extruder which has tremendous applications. Our proposed project can print a structure with multi-material polymers and graphene-based sensing material which can be cured with a UV light source. A multi-nozzle head module is mounted on a 3-axis NC servo-controlled platform. For a material with different viscosity, the extrusion outlet flow rate is dependent on the used nozzle parameter and applied pneumatic pressure.

This is just the tip of the iceberg, with our multi-material pneumatic extruder industries can save a lot of time and money and help with many commercial uses.

Technical Details of Final Deliverable

Our main objective was to fabricate a portable 3D printing pneumatic extruder that could print materials of different viscosities. We had to ensure that the 3D prints by our extruder were precise with minimal line width to print materials with sharp edges. Air compressor combined with pressure regulator ensured that the materials from different viscosities could be extruded. Each material required several tests to make sure an optimal pressure was selected for proper extrusion. Moreover, to achieve minimal line width we selected a nozzle with minimum diameter that could perform extrusion without clogging. We also conducted tests to get an optimal printing speed that provided a uniform line width.

Furthermore, Marlin software which is an open source that allows our pneumatic 3D extruder to be integrated with any existing 3D printer in the world. Our team also ensured that our pneumatic extruder works in a single pass and doesn't print the same layer more than once, which can cause liquid materials to disperse from its original shape.

Final Deliverable of the Project HW/SW integrated systemCore Industry ManufacturingOther IndustriesCore Technology 3D/4D PrintingOther TechnologiesSustainable Development Goals Quality Education, Decent Work and Economic Growth, Industry, Innovation and Infrastructure, Responsible Consumption and ProductionRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	30000
Dispensing Controller	Equipment	1	18000	18000
Nozzles and Syringes	Miscellaneous	1	4000	4000
Power Supply 12V 20A	Equipment	2	2900	5800
UV Curable Resins	Miscellaneous	1	2200	2200