In article ,
Jon Anderson wrote:
John,

[ ... ]

Currently has no means to quantify performance.
They are, his description, air coil, or ironless rotor motors. Fast
response, low inertia, low HP.

These sound like the servo motors used in CNC machine tools.
The low rotating mass leaves you with only the mass of the table and
workpiece (or whatever else is being moved) to tune.

Enjoy,
DoN.

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