I found this interesting(see 1171 C. Phoenix):
[
www.molecularassembler.com]
The basic idea is to use paper tape and a fluidic computer to control hydraulic arms to machine UV curable plastic.
A fluidic control system has several advantages over an electronic and mechanical control systems: fluidics don't have to be built terribly accurately, fluidics don't need to be made of several different types of materials, fluidics have no moving parts(unless you consider the fluid to be a moving part). This makes fluidics quite replicable, a reprap built using fluidics might approach 80-90% total part replication.
The only problems with using a fluidic control system are the need for a continous supply of fluid, reprogramming the enormous paper tape for purposes other than replication, and size. Though the last problem could easily be solved through miniaturization.( [
www.rsc.org] )
A fluidic transistor:
[
blog.modernmechanix.com]
Fluidics basics
[
www.tippettsfountains.com]
A fluidic gramophone(potential method for storing programs in a more compact manner than a 1400 ft paper tape)
[
www.dself.dsl.pipex.com]
Fluidic logic gates
[
www.blikstein.com]
[
www.trnmag.com]