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Rotational Robot Solder Web Interocitor
Well, not interocitor, but something that dynamically surreptitiously interrupts, holds it there, and, its work having been done, gets out of the way again
Originally, electronic manufacturing didn't really involve circuit
boards. They might have involved a 'board' plane or substrate,
maybe holes in, to hold soldered components, but they could just
easily have used many solder-tags to straddle components
A lot of valve radios
for example didn't have actual circuit boards.
The very first bit of electronics I ever made as a very young single-
digit-old child was made by following a ladybird book* on making a
radio. It used drawing pins pushed into a bit of softboard, and
soldering the components between them. From rough memory, it
involved a ferrite rod and hand-wound coil, a tuning capacitor,
resistors, two or three germanium transistors (Mullard OC71 and
probably OC45), big old germanium diodes, crystal earpiece, or
it a loudspeaker, and some other stuff. I don't know, it was in the
60s. But the important thing here - no circuit board.
At the moment, you can solder components to a circuit board, on
fairly large scale, and machines can solder smaller components to
smaller circuit board, on, yes, a smaller scale. You can use
veroboard (or stripboard if you order the horrible stuff from china)
or you can make your own pcb. Surprisingly it still isn't as easy as I
think it should be to make a pcb even in these 'maker' (pfffphh)
Well, 3D printing? Forget those ludicrous laminations. Yes - robots
Imagine a robot that could hold a pair of components in close
proximity. Imagine also that the holding jaws or mandibles or
grippers had rotational capability, but further than that, orbital
capability, such that they could hold a pair of components and a
further soldering limb could apply molten solder to one
solder land while it was held in such a position that the solder
slightly downward, and then rotates as the solder stream slightly
solidifies, to angle or mutate the direction of the solder flow, and
meet up with the other component solder land, all very quickly
accurately. There wouldn't be much requirement to leave very
strands between components, and solder doesn't have the strength
anyway. The connections between components only need be short
enough to bridge components and leave room for the other
components in the circuit assembly.
The advantages of this are that the circuit assemblage can be
considerably more '3D' than they are at present - most circuits are
laid out on a plane, because that's the way we design a PCB, and
that, because that's the way we design a circuit diagram. I
this idea using SMD (or MELF**), but of course, such surface mount
no longer mounting on a surface as such - this is surfaceless.
I suspect solder bridges or solder streamers alone might not be the
answer, though - I think it might be necessary to 'tig' actual solid
wire between the component lands to establish a 'shape', then
to flow proper joints at each component land / wire end junction.
However, the wires can be positioned in a 3D space freely, and of
course, be bent to optimise the shape.
It'd be quite superb to see this optimised by AI, such that all you
have to do is give the robot the circuit diagram and bins of
components and it computationally finds ideal orientations and
for the circuit, then makes it.
* 0721403247 was the isbn - if you want to search for it
** Most End up Lying on the Floor
[Ian Tindale, Mar 24 2017]
The way the LM13600 operational transconductance amplifier was lashed up as a prototype (with a stereo photo!) [Ian Tindale, Mar 25 2017]
||Yes, but what happens when your circuit is built? How do you put a bird's nest into a nice case?
||I'm not searching for that, looks too much like a premium rate number.
||At high frequecies, the inductance and capacitance of the substrate becomes significant and has to be allowed for. A 3D mesh is going to be a nightmare ...
||You make it sound like a bad thing.
||[+] free range circuitry.
||I don't think solder would cut it : Russian wire wrap perhaps (post wrapped around wires), and the leads need to have springy properties.
||So, what happens when the circuit fails, and you (a) can't reach the suspect component with your multimeter probes because of all the spaghetti an and (b) have to unmantle half the circuit to get to it anyway?
||//circuit fails// Embeded easy access to test/bypass points
little LEDs to light the way. Field embedding is on the way.
||True, in-circuit testing is more problematic in this scenario.
That'll have to be solved. Probably with quantum
||I must say, I'm not a fan of wire-wrap techniques. When
that became a bit of a craze in the 70s, the electronics
world predicted we'd never solder again, that those days
gone. We still solder, though. My objection to wire-wrap is
aesthetic - it is ugly.
||What I'm describing here is a technologically enabled and
enhanced version of the 'Christmas-tree' assembly
technique many of us have used at one time or another to
lash up a basic prototype of a simple circuit - you just wire
the leads of a component together to other leads of other
components, in free space. This is almost never used for
actual production, but for prototyping it gets you going
quickly. Indeed, I remember seeing photos of the
prototypes of various ICs made from lashing together other
components in christmas-tree form, to establish the
connections. Then the real thing can be drawn up and
||What this does, then, is legitimise the christmas-tree
approach, and not by using through-the-hole types of
components (which are becoming rarer and costlier, while
SMD become cheaper and smaller) but surface-mount
devices and drawing or forming conductors between them
in free space, in three dimensions as opposed to sticking to
a flat plane.
||I suppose disassembly becomes manifold more difficult. I'm
tempted to say fuck it, that increasing reliability of SMD
components mean a measurably lower incidence of
servicing as opposed to whole-unit replacement, but I don't
have numbers to back that up.
||//It'd be quite superb to see this optimised by AI//
||"Assuming a maximum ambient temperature of 35 degrees C, and no cooling plane, the size of your circuit will be 30mm cubed. Are you sure Dave ?"
||Another actuator arm could jet a narrow beam of cooling
air, which itself might work as a calculatable manipulator
by blowing the cooling solder in a direction.
||I suppose one thing that would improve this idea is to move
away from solder to something more like welding tiny rods
of welding rod. A fundamental difference between
soldering and welding and glueing is that welding involves
basically the same material to form the joint as the
material we are joining. Hence, plastic welding uses a
mixture of the same sort of PVC and / or ABS as the plastic
pipes you're welding. Glue is not that, it is a separate
material that forms a bond in between the parts. Solder
similarly is strictly not welding and almost more glueing, in
a way, by the solder being a filler material that melts at a
much lower temp than the component leads or terminals
||Well, OK, [Ian], you've won me round. [+]