The Concept

Modern robotics hardware for the hobby market has been reduced to a series of modules, from servos to processors. The only things connecting these together are wire and chassis, and I've been experimenting with using easy to obtain materials to build those chassis. Polycarbonate and polystyrene, polyethylene, sheet aluminium etc were natural choices.

Mark's IO made me think again about the validity of cardboard as a working material, and we began a dialogue that culminated in this collaboration.

The idea was to use a single sheet of craft card and a printed template to create chassis units that connect the electromechanical building blocks together.

We have since iterated over a few changes to the design, incorporating better geometry to give the parts strength, room for cabling and better overall appearance.

First generation limb built by Mark N during the initial prototyping.

Origaime - The next generation

The updated parts built in exactly the same way as the first set, they fold up from a single piece of cardboard to make a modular piece for the robot. Mark calls this Origaime, after the original robot that inspired everything and the art of folding. :-)

Both these pieces were accomplished using the redesigned saddle that fits over the servo actuator and a stud fitted opposite it to make a live hinge.

The section that joins these together to make active limbs as also made from one piece. This part carries the servos and the stud for the saddle to rotate over. Eventually there will be a range of part styles that can make any articulation you like, not just basic limbs.

Other Materials

We've looked at other materials besides cardboard after realising that self-recycled materials were also a possibility. The initial discussions for the project touched on the fact that paper and card were already a recycled material besides their other qualities, but the inclusion of @markgeo to our collaborators brought this to the front quite literally as he attempted a build of the early generation limb parts using cardboard scavenged from cereal packets. This was necessary as he is developing Cardware in Thailand where card stock and other things we take for granted are not so easy to obtain. MarkG is using this ability of the system to promote robotics in education there, as other resources needed to teach the subject are not easily available.

He has written an interesting piece about the technological shift in Thailand, where this is particularly relevant. This particular competition was open to European countries too, and we got our backsides kicked.

MarkGeo's outstanding build using recycled card.

Here Markgeo talks about the impact different cultures have on what we are trying to achieve.

Inspired by Mark's hacking of my system using materials I'd not considered before, I looked around myself for something suitable and previously considered trash.

I'd thought about plastics, and tried PET for its monumental strength and ability to take a crease without snapping. It's hard to glue, but the parts are indestructible in normal use. Cardware with 200GSM card will survive a minor tumble but a few feet before impact will crush the folds under it's own weight. The PET sheet I bought specifically to test is thicker than a soda bottle by a small margin and the resulting limb impervious to unmaking. I tried without success.

Cardware Forever

I'm figuring that a soda bottle will have similar strength but cost nothing to obtain. Forgive the picture quality, another odd thing about PET is it is IR transparent so the autofocus does not work and tracks the background instead.

Thinking along the same theme of recycling I purchased some lager cans and set about separating them from the contents. Now this is recycling I can get into. :-) It proved to be such hard work that I had to sleep on the project and began in the morning hampered by a strange headache. Despite...

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