Hi- I'm trying to build a simple linear motion control using a solenoid. I've replaced the typical steel core for a permanent magnet core so that I can both push the armature out and pull it back in by flipping polarity (and without using any springs). This works nicely. Unfortunately, it still can only go full out or full in, like a regular solenoid. I would love to be able to add a stopping point mid-way. So in effect, I could 3 positions - In, halfway out, all the way out - and still be able to go both directions. Is this possible? Perhaps with a core that is some combination of reversed polarity magnets and a steel core? Or with a steel ring that acts like a mid-point latch? Any ideas are helpful. Thanks!