Sorry to take the focus away from global warming and
child aggression, but has anyone done open-loop
solenoid driving, specifically to make a solenoid
move SLOWLY by a simple PWM waveform??

I need to make a solenoid either pull-in or drop-out
(either is ok) but slowly.

Assume a 12v solenoid with a simple spring and about
6mm of travel. The solenoid armature and load have
constant mass, spring tension will remain similar
and friction is within a predictable small range.

Is it feasable to just kill the solenoid current,
wait a time for the armature to travel small distance,
then give a short current pulse to halt armature
movement, then repeat a couple of times? I'm guessing
that a few correctly timed pulses would give an
armature release of maybe 0.5 seconds compared to
the normal release time of <0.1 seconds?
-Roman

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