My immediate thought: how could this be used to make a really cheap desktop pick-and-place system?
This has the potential for:
* way less material cost
* way less assembly, and
* way higher reliability due to fewer moving parts
Even smaller ones...
The limitations of homebrew pick-and-place are the vision system, not the control system.
If you solved the vision system problems, you could probably build a pick-and-place out of Legos.
Someone made one, and it’s amazing.
Most likely not, but bio/chemical experiments yes.
Stepper motors have multiple teeth per pole: https://en.wikipedia.org/wiki/Stepper_motor#/media/File:Step...
The rotor has slightly fewer teeth than the stator, such that one "electrical rotation" (each coil being switched on in sequence) causes the rotor to advance by the number of missing teeth. That is what makes a stepper so precise; it gets 4+ divisions per tooth.
motor typology is not well defined, so we're arguing a moot point. That said, I think this is a poor criterion for stepping. BLDCs, SRMs, and doubly-wound machines are all steppers by this definition. IMO it is not useful.
All motors which are called stepper motors have one unique thing in common: they take multiple electrical rotations per mechanical rotation. This motor does not do that.
Yeah, of course it doesn't have the same design of the steppers you buy around. That's obvious from the title alone. That doesn't make it not a stepper. And yeah, it's less precise than the ones you can buy¹. That should be expected too.
1 - Although, that conclusion is way too simplistic to make. It has a different kind of imprecision, so depending on how you compare, you may as well conclude that it's more precise.
BLDC, series wound, and switched reluctance motors will also hold their position. Cogging torque exists in the majority of motor types. It is not very useful for dividing motors into families, and is certainly not specific to the group of machines called stepper motors.
If you energize each coil of a BLDC, series wound, or SR motor (not the wires, each actual coil) in sequence, the shaft of the motor will rotate once (or very close to once). If you do the same with a stepper motor, the shaft will have turned 22.5 degrees or less.
It is possible to make a linear stepping motor. The Vernier scale is basically stepping as applied to measurement. This is not that.
Edit: Glad he mentioned Carl Bugeja's youtube channel, this instantly brought Carl's work to mind.
[0] https://www.youtube.com/watch?v=xPUEOhMBpUw (in German)
I wonder if you could use induced currents in the pucks instead of permanent magnets to create the opposing force. Then you could tune the PCB coil to target specific elements. So 212kHz moves puck A, 241kHz moves puck B, etc
Thanks for the suggestion nonetheless
(note that i reverse a few frames in the loop to be less jarring visually, the current is probably not correct when the puck is moving left)
I wonder if vibration would help reducing friction. I.e. superimposing a low-power high-frequency component in the field to avoid static friction.
