Hello guys,
I'm motorizing a filterwheel for my telescope. It has five holes where you can screw the filters. I placed two hall sensors (A1302): one for the "home position" detection (first filter) and one for a generic filter position. I also put magnets near every filter, equaly spaced thanks to a cnc design and performing the hole for every magnet. The rotation is allowed thanks to a 28byj-48 stepper motor with a rubber ring on its shuffle and it trasfers the motion to the edge of the wheel. Rotation is quite perfect even if I would play with speed in order to get less filter switching time. At the moment I have some problem with hall effect detection; if a manually put the filterwheel in the right position for a generic filter and I get the value of the sensor I found it is not the same read while the wheel is moving and pass over the same magnet: the raw read value is always higher than the one read if I put the sensor aligned to the magnet (in my case higher raw sensor means lower magnetic field). It's like the space between a step and the following one is too wide to get the real best position value. Even if I can play with offsets value for each position, I'd like to share with you this issues in order to get suggestions for improving the solution. I don't know if it is something related to sensor or motor so I decide to put this post in this section, I hope I did right.
Thanks in advance for you attention.
Cheers,
Giovanni.