# Robotic arm chassis

I've been curious about how the plastic chassises of the robotic arms in robotic competitions are manufactured. For instance, the following arms clearly have 10-20 plastic parts each, if not more:

Injection moulding such large parts can easily cost \$5k per mould, so it wouldn't quite make sense to me that university projects would spend \$100k into the chassis production alone when only merely several units are needed. By looking at the finishing, they don't seem to be 3D printed. How are the chassises actually made though?

• All of the robot examples you showed are purchased machines. – morbo Aug 9 '19 at 17:10
• @morbo In that case, does that mean the challenge is mostly a software challenge then? Is it fair to say that the teams involved didn't make hardware innovations? – Kar Aug 9 '19 at 19:34
• At most new tooling. Generally those comps would be for planning innovations, or the like, as you said yes – morbo Aug 9 '19 at 19:50
• @morbo What do you mean by tooling? – Kar Aug 9 '19 at 20:05
• End effector i suppose would be more common to say – morbo Aug 9 '19 at 20:15