I was planning on 3D printing my own 30 cm stroke length 3D printed linear actuator and I don't know how I could read its position, or tell it to go say to 16.5 cm. I used this video, 3D Printed Linear Actuator??? Surprisingly Strong!, as reference
Issue
The problem is, the guy in the video is using only 2 mechanical endstops, which won't work for accurate positioning or anything between 0 and 30cm. Not only that, but since my actuator needs to be strong I will have to print a planetary Gearbox of 10:1, which means the input and output shaft will have completely different rotations, and thus positions!
I looked into Absolute Magnetic encoders and found this video of the AS5600, Measuring speed and position using the AS5600 magnetic encoder. And I had two problems:
What happens if the rotation goes beyond 360 degrees? Does it go back to 0?
And it turns out it keeps incrementing the value as shown in the video, so it won't go back to 0.
BUT what if we cut the system power? Will its position be remembered? Say it was at rotation position 1053.2, will it go back to 0 when the power comes back? This will lead to losing the position data!
The solution I thought of
So if the position is not lost at power off, then calculating the position of the gearbox output shaft would be very simple:
Output Angle = Input Angle / Reduction Ration % 360
(If I got it right)
And it would be as easy as mounting the encoder on the back of the driver motor!
Is this right? Does the encoder remember the position even after the power off? Do you guys have experience with any absolute encoder that can do that, and NOT return to 0 once it reached 360 degrees?