From: null@void.com
"Jim Wilkins" writes:
> "Richard Smith" wrote in message news:m1a52o6uwz.fsf@void.com...
>
> "Jim Wilkins" writes:
> ...
>
> You were forced to overspecify everything... ?
>
> "The pigs all had their snouts in the trough".
> By this everyone can get paid for doing nothing.
>
> -----------------------------------
>
> Sometimes, depending on conditions. When trying something new
> available products are rarely a close match, and industry required
> what appeared to be overspecifying based on previous incidents, like a
> forklift puncturing an electrical cabinet. That resulted in the
> requirement that all internal hazardous voltage be run through
> grounded conduit so a short would pop a breaker, and regardless of
> power level any exposed wiring outside enclosures had to be too strong
> to break accidentally or intentionally by hand, 16AWG. The external
> panel controls had to be oil-tight to protect them from conductive or
> flammable coolant spray from whatever they were placed beside and
> soapy water wash-downs with a hose. Oil-tight switch controls were
> several times more expensive, and modular so their switching functions
> could be changed with a screwdriver, such as single pole single throw
> to double pole double throw. Lab equipment wasn't subject to those
> requirements but we met them anyway since we were prepared for
> them. Delivery is quicker if you have stock on hand and charge for its
> replacement. I do that for common hardware at home too.
>
> Idiot-proofing encourages hiring cheaper idiots as operators. The
> history of infantry weapons and tactics demonstrates this when
> compared to artillery which required more careful handling. An example
> today is singers dropping a fragile and expensive professional
> microphone. Air hose nozzles became vented and less effective because
> some idiot worker once pushed a high pressure nozzle against another
> and punctured the skin.
>
> Automotive electronics can be subject to nearly the temperature stress
> of fighter jets, for example a snowplow in Alaska (or NH) starting
> cold and ramming at full power into a snowbank, or being splashed with
> icy water. As an apprentice I helped assemble a large expensive
> machine that rapidly cycled a batch of GM HEI ignition modules between
> hot and cold limits while testing their proper operation. If a loose
> or corroded battery clamp disconnects the alternator can generate
> around 100V until the energy stored in the rotor has dissipated and
> the voltage regulator regains control of rotor current.
>
> Aviation electronics had to at least stay in place during a shock of
> somewhat over 30 g's (?) so they wouldn't fly into the cockpit during
> a rough belly landing. That one was a mechanical engineer's problem to
> solve, as was adequate cooling airflow at altitude which seemed
> excessive on the ground. Some WW2 aircraft engines fed supercharged
> air into the distributor to avoid sparks jumping at high altitude.
>
> Submarines were/are? tested to the pressure equivalent of 10,000'
> altitude. Diesels pull a vacuum in the hull if the snorkel closes from
> a large wave. The radar stealth coating on WW2 U-boot Schnorchels
> didn't hide them from the latest secret Allied radar, the boats were
> out until the war's end but ineffective after spring 1943. Those are
> examples of conditions one might not expect or design for.
>
> New equipment intended to test other new equipment sometimes needed
> modification as the specs changed, using components with higher
> ratings was a valuable hedge. An example I can mention is the Apollo
> spacecraft flight control computer that had more computation to do
> during the actual moon landing than had been expected or tested
> for. It's supposed failure was a watchdog timer lamp that flashed
> because the program couldn't cycle through all tasks in a
> pre-specified time which had been initially assumed to be more than
> adequate, and could be changed in hardware if the programmers knew to
> ask. The program loop's final task was to reset the timer that kept
> the light off, presumably unless the computer crashed. I heard that
> from the Mitre engineer who had helped design and build the
> computer. He was on other tasks when the computer was being tested.
>
> I don't intentionally overspecify on home projects that I can easily
> change unless the available material is more capable than needed or I
> don't know the worst condition, such as the starting shock load of my
> electric hoist or the maximum starting (locked rotor) current for an
> electric motor running from a DC-AC inverter. Measured results vary
> widely depending on the random phase at connection and the inverter's
> surge capacity is also unknown, and indeterminate until I buy one.
>
> I designed the tractor bucket loader for an impact that would lift the
> rear wheels off the ground, but didn't know the weight capacity of the
> front tires and axles so I machined an adjustable hydraulic pressure
> relief valve and crept the pressure up until a tire failed. I collect
> used test equipment to be able to measure these things.
What I meant was - not well explained - they overspecify the path to any
goal.
My discoveries and successes have been through "feeling my way along" -
sensing what Nature is revealing and adapting. Life is what happens
when you are making other plans - have a plan yes but adapt it rapidly
with what you find as a result of driving on determinedly on the
plan-so-far.
My perception of a lot of "go nowhere machines" of organisations is to
immediately specify everything. Superficially it sounds right - but if
you have any experience of science, you know it fundamentally absolutely
doesn't work that way.
My understanding is that in the USA there was a lot of discretionary
funding of good ideas. eg. the Internet happened because of
"long-haired hippies" asked to find a communication system which was
impossible to disrupt and provided funds to "give it a try" to ideas
emerging.
Then there's been competions like which produced the "Reindahl" (sic.) -
128bit-key - cryptographic algorithm and self-driving logistics
vehicles.
Etc.
Surely have related before - I once was treated to the distressing sight
of a colleague curling over the desk his face red, blood vessels pulsing
on his temples, making and anguished acting-out of strangulation --
because disguised in jest I was trying to steer them away from thing
"ISO54321 / EN0123 / ISO....." approaching the investigation of a
problem / discrepancy in Non-Destructive Testing.
Fortunately three days later they were looking at exactly what I had
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--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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