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The world of medicine contains many things, conceited
surgeons being a routine fixture. Give them the
opportunity, and if you're deemed worthy, they'll tell you
how wonderful thins new-fangled keyhole surgery is, in
through a navel, past 2 loops of bowel and a kidney, snip
snip, all done. With
a minimum of disturbance.
This technique was of course well established by
mechanics who didn't fancy lifting the engine away from
the gearbox and grinding off an exhaust manifold just to
change that last spark plug*.
instead, long, bendy tools, a little contortion and a liberal
attitude to how far things should bend is used** instead of
wholesale disassembly.
The problem with all this, is that eventually, the 10mm
socket you taped onto the end of you're quadruple
extension will drop off. It won't do anything helpful, like
fall all the way to the floor, oh no. It will drop and roll in
behind the intake manifold. Probably in plain sight***
taunting you. Can you leave it? Well, you're probably down
to your last 10mm socket, everyone is, and it's likely sitting
right next to a drive pully that will not come out on top of
a high speed interaction with tool steel.
So, you go and get your grabber tool. There are two types,
one is a springy plunger-operated flexible tube that has
spindly arms that pop out of the end to grab your socket,
the other is a version with a permanent magnet on the
end.
The downside to the magnetic version, is that magnets are
happy sticking indiscriminately to almost anything in the
typical engine bay. So, let's solve it.
Take a small electromagnet, put it on a flexible thing, run
wire, add push button momentary switch and a battery at
the handle end. You're done. Switchable magnetic grabber.
* of course I changed it guv, look, there's 6 empty spark
plug boxes. What more do you want?
** in some vehicles. In a Ducati, you're on your own, son.
*** from one very specific angle
[link]
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Nice, but an equally effective technique is to guide a length of 10mm i/d PVC tubing down to just above the errant tool, then thread the conventional magnetic grabber through it. When it pokes out of the end and attaches to the item, then both components can be pulled out. |
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When not in use, the two items can be stored concentrically hung from a shelf or a rafter. |
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Bun anyway; but extra pastry if the device is powered not by a cell or cells (which inevitably rot, destroying the device) but by a small hand-cranked generator, ensuring that it is always available even in difficult or remote locations. |
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Trying to imagine simultaneously hand-cranking a generator whilst guiding a magnet through a maze of twisty steel orifices. |
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Anyway back to this idea, won't the energised electromagnet still try to stick to everything on the way out? |
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//extra pastry if the device is powered not by a cell or
cells// |
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Oh, it will. USB rechargable, and, mysteriously,
sophisticated datalogging. Plug in a laptop, and for no
good reason you will be able to map grabbing events over
time, see frequency, duration, maybe some back EMF to
gauge object size. Then the more experienced user will
be able to tweak parameters, maybe you want a ramped
electromagnet profile to get finer control of your grab.
There should also be choices of N vs S pole grabs, maybe
a pulse profile to wiggle-jiggle a trapped screw. Anyhow,
point is, the software should be dramatic overkill. This
should actually be easy, it's essentially 1/3 of a BLDC
controller, but don't tell anyone. |
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Definitely the slow class. |
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1. Guide electromagnet to target item. |
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2. Start cranking to grab item. |
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3. Pull gently on shaft attached to electromagnet. |
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//simultaneously hand-cranking a generator whilst
guiding a magnet// |
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in 8th's version, I guess you do the cranking before and
charge a super capacitor, then you feed your magnet in,
then you switch it on. Should be very doable, a 10x20mm
electromagnetic grabber in industrial process control runs
about 5W, which for the <10s you need is easy. |
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My version is running on rechargeable Li-Ion, I need the
power for the control software. Although I take 8th's
point about suitability for field deployment. So, for the
military version it will be permanently powered by a solid
state radioisotope thermal generator (ooooh, idea). The
civilian one, will take those little gas cartridges used for
soldering irons/mosquito repellent things. Both could also
have a compressed air inlet with hideously inefficient
turbine generator, because compressed air always seems
to be available whenever serious mechanic-ing takes
place. |
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It may be too obvious, but since you are using electricity you could just put a camera and light on the end of the grabber. |
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The narrative and idea are each top notch. |
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How about an attachment to the lift that will tilt and gently shake the whole truck? |
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A flexible stick with an end having a blob of space-time, in the form of quantum electromagnetic music, that matches the object to be held might be the future go. |
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Doesn't stick to anything except the target. Might be attracted even. |
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Then again, just use the right claws. |
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