By Mirza Rizwan
In recent years, 3-Dimension (3D) printing has evolved as an additive manufacturing technique since its first use of it in the 1980s as rapid prototyping in the manufacturing sector. This additive manufacturing technology is capable of creating complex geometrics products into one-piece production without the need to assemble, unlike that of traditional manufacturing techniques such as formative and subtracting manufacturing. It has the added advantage of faster processing, low fixed setup costs and highly customised manufacturing. Interest in 3D printing technology abruptly shot up in 2005 with the launch of ‘Replicated Rapid Prototyper Project’ wherein self-replicating 3D printers were capable of printing their own parts.
However, this manufacturing technique cannot replace the traditional one due to the limitation of material and mechanical properties of the desired manufacturing goods. It is best for low volumes, complex designs and for higher speed, and for these very reasons it is expected 3D printing will open a sea of opportunities in the defence sector in terms of instant on-demand replacement parts, localised production, reduced wastages and production costs, design flexibility and maintenance of military systems by producing spare or obsolete parts.
The world’s top defence forces are extensively using 3D printing solutions and investing hugely in 3D printing research and development. Some of the remarkable solutions are the erection of quick-drying concrete used for on the site bunker structure through 3D printing technology in a time span of 36 hours and good enough to hide a truck. The structure could be from shelters to bridges just with an intuitive command on a tablet or smartphone touchscreen to be executed by the robotics system. 3D printing solutions have been applied to manufacture defence products at the ongoing combat location, right from the custom prosthetics to critical parts of aircraft engines, tanks and submarines. The possibility of customised 3D printed garments with embedded electronics such as built-in communications, sensors or bio-monitoring systems for soldiers is high.
Sensors could even be printed directly on the skin of the soldiers to be used on the battlefield to capture solar energy and charge small electronic devices. The aerospace industry expects 3D printing will slash their production time to catch up with the aircraft demand backlog which doubles every 15 years. Some of the aerospace and defence companies that incorporated 3-D printing to bolster production are GE (jet engines, medical devices, and home appliance parts), Lockheed Martin, Boeing, and Aurora Flight Sciences (unmanned aerial vehicles). In fact, Aurora Flight Sciences are printing the entire body of a drone in one building.
Beyond 3D Printing
3D Printing is a layer-by-layer print path of a 2D structure from bottom to top till the 3D volume is created. When this 3D Printing technology uses smart material ‘Hydrogel’ or ‘Shape Memory Polymer (SMP)’ having thermomechanical properties, it adds a fourth dimension over 3D printing technology of its ability to change shape over time. MIT Self-assembly Lab referred to this breakthrough as 4D Printing technology where finished products have the influence of external energy input as temperature, light or other environmental stimuli. The other material feed for the 4D Printing process could be metamaterials like those of thermoplastics, self-healing polymers, metals, and nanocomposites. Those with low strength and stiffness would be most suitable. The remarkable potential application of 4D Printing would be water pipes that dynamically change their diameter in response to the water flow rate. Pipes could also possibly heal themselves if it cracks due to their ability to change in response to environmental change.
4D printing is going to revolutionise the world of materials and product design mechanisms. It will open the imagination of the products in terms of shape and functions which could not be possible in normal circumstances, something like self-assembly furniture which could be used as a cot, table, chair and box at the different time and shape needs. Think of a flower that blooms in sunlight and contracts as flower buds at night. The 4D printing technology will have immense application in the manufacturing sector across the industry to disrupt not just the manufacturing process but the product kinds and features as well.
What’s Ahead?
As the 4D printing technology is going to disrupt the industry on account of manufacturing design beyond the imagination of the human mind, it requires extensive research and development on every aspect of this manufacturing process outcome. The future might bring surprises that look strictly logical in hindsight but are hard to picture today. 3D and 4D printers of high capability might replace highly skilled workers and humans might work only to service the printers. The transformational process of mass production to mass customisation will leap into fame in terms of product, process and system perspectives. The biggest challenge would be quality assurance and control of the units produced through additive manufacturing. Sustainability and reduced environmental impact would be the added advantage. The next global manufacturing superpower is going to be the one who will be having an R&D edge in 4D printing technology for additive manufacturing.
About The Author
The writer is a US National award-winning serial innovator with 34 patents pending with US and India patent offices. Known for revolutionising education in the United States by developing and implementing courses to teach young kids to innovate. He is currently working as Chief Innovation Officer with Si2 Microsystem, where he is responsible for leading and managing global innovation teams to deliver high-tech solutions in the aerospace and defence industry.
