"James Waldby" wrote in message
...
If you have room for a slack loop you might be able to cut
down the number of start/stop cycles by a factor of two or
three. With a slack loop and an adaptive speed control the
motor might be able to run continuously.

Yeah! Do it like the old reel-to-reel computer tape drives with a
"compliance arm" that provides the minimum tension on the wire you require,
then spools out, brakes, or retrieves with a direct-drive DC servo motor
depending upon the position of the arm.

If the arm is pulled more "outward", the motor speeds up to provide slack
until the compliance arm tension is correct again. If the arm is allowed to
slack, it can either reverse and take up wire, or it can brake to a stop --
depending upon your needs. With enough sensitivity in the feedback element
on the arm, you can keep the tension almost constant to a high degree of
precision.

Such a mechanism could provide "available" wire all the time, regardless of
the direction the end was moving.

LLoyd