RoboThespian Wearing 3D Glasses

Prepare Your Red and Blue Glasses... Engineered Arts goes 3D!

At Engineered Arts, we make great machines. To make these great machines, somewhat ironically, we need "other great machines".

We are always investing in ways to make our products, better, more efficient, stronger and lighter. One of the ways to do that is to buy new kit. From the humble Philips screwdriver all the way to our catchily named Mazak Integrex i-100 Bartac-S, our monstrous 5 axis CNC machine. All of our varied CAM machines share a common theme, they are subtractive. Meaning they make parts by taking away material from a larger block of material. A tried and tested methodology, employed from as far back the ancient Egyptians. The problem is there are just some geometry and material types that can't be manufactured. There is always an element of waste material too. Often these get recycled and you get some of the value back. But it is by no means a perfect solution.

It's possible to see just two of our subtractive CNC machines in the background of this video of RoboThespian ranting about artificial intelligence, in the first of his series of rants in Robot's World. The second video shows how we make just one of the many RoboThespian parts using our Mazak CNC machine.

So Why Change Anything?

If we are able to make our robots using subtractive methodologies, why change anything? What not many people realise, we don't just make RoboThespian and Socibot. We also make custom commissions for various world-class visitor attractions, designing and building robotic solutions, some of which are not even human in form. Occasionally these require unique geometry or material properties that are just not feasible, using traditional subtractive methods.

In recent years there has been somewhat of a revolution in additive manufacturing. 3D printers of all shapes and types have been popping up everywhere. Although the process of additive manufacturing is still in its relative infancy, we are now starting to see some real uses. 

Sooooooo...

We have invested in 3D printing. More specifically we have bought not one, but two 3D printers.The first of two is an SLA or Stereolithography apparatus printer by FormLabs. The Form2.  

RoboThespian Points at FormLabs 2

This also allows us to make rapid prototypes of new parts and assemblies with extreme detail to the resolution at the 140-micron level. We have already put it to good use on some of our custom projects. Creating organically shaped parts with minimal fuss, and a great level of finish and accuracy. We have found that it 'just works'. This is due to a combination of, high-quality hardware and superbly well-integrated software. At this moment in time, we can't show any images of prints due to confidentiality of the projects we are working on. But rest assured we have been staggered by the results achieved so far. Specifically, we have been able to use 3D printed parts alongside subtractive parts seamlessly in deliverables to clients with a 100% satisfaction rate.

There are however some drawbacks to using this machine. One of them is print time. Not necessarily a criticism of this machine per se, but more of a comment on where 3D printing is at the moment. We have been printing some intricate parts, and we have seen print times ranging from 4-8 hours. Fine for occasional one-off parts, but too slow for manufacturing of any sort of scale. To increase the time efficiency, you would be required to scale the number of printers. 

Another issue is the part size. You are forced to build small parts (145×145×175mm) or split large parts into smaller ones. This is one reason why we have purchased a larger printer. 

Step in the Markforged mark 2

Socibot Kiosk looks at Markforged mark 2

So there are two major differences with the MarkForged mark 2. First is the print size of 320 mm x 132 mm x 154 mm. Second and probably the biggest change is the method in which builds are printed. Rather than SLA, this printer uses FDM or 'Fused Deposition Modelling'. Which essentially a very fancy hot glue gun, printing layers of molten material extruded into a 3D shape. An advantage of this method is it is easy to use additives to the basic nylons, to change the properties of the parts depending what you require. Additives include Carbon Fibre, Fibreglass, Kevlar HSHT Fiberglass (High-Strength High-Temperature Fiberglass). This allows bigger, stronger parts that can withstand much more tough environments.

A problem with this methodology is that is not as high resolution as the formlabs printer, meaning often the parts don't look as pretty, with visible (although fine) layers. This is better for strong internal components, rather than high complexity, outwardly visible parts.

...In conclusion

The rest of our machines can breathe a sigh of relief (for now), as they will remain to be used for most of our manufacturing. 3D printing isn't good enough to replace them yet. But it is getting better, and we are now able to leverage the technology in some unique situations, which broadens and improves our already impressive in-house manufacturing capability. Hopefully, we will be able to show you some printed parts soon.

That's all for now 3D fans!