Variable Induction Propulsion Experiment
If you push a core into a solenoid the core will be sucked in if it increases the inductance of the coil.
I took a two pole motor and seperated the two windings so that you could make the coil fields aid or buck each other. If the fields aid, north pole to south pole, a core that is not centered in the field will be drawn into the field.
If the fields are bucking then it will take force to push the core into the center of the field. It occured to me that since the fields are oriented perpendicular to the direction of motion maybe we could get propulsion by pushing a core into a motor. Say we are pushing the core into a motor with the poles bucking. It will make the core we are pushing feel heavier. When the core is fully in then we remove the current for the poles. As we withdraw the core it should take less force as the core will seem lighter. Possibly the linear force of pushing the core is not directly passed to the motor coils, possibly there is some force for expansion or contraction of the motor body in a perpendicular direction. I built a reciprocating device that pushed a core into a motor stator as pictured with the field coils energised only while
the core was being pushed or pulled in one direction. How well did it propel itself? I could not detect propulsion but I only did a qualitative test. Watch the video, you be the judge.
Video of Variable Induction Propulsion Experiment