I’m looking for a micro linear actuator with highest precision, resolution, and position repeatability.
I tried Actuonix digital, it is good, but has low resolution in low positions.
Interesting, I looked into the PQ12 datasheet, and that has ±0.1mm positional repeatability:
My 3D printer uses stepper motors driving lead screws for linear motion. Very precise and repeatable. The axis must be “homed” at startup to establish a zero reference and the motors must be powerful enough to never miss steps. No feed back required and low cost. The lead screws and steppers on my printer gives 2560.00 motor steps per millimeter. 8mmx1.25 lead screw, 200 steps per rev, 1/16 micro stepping.
Until today I have never worked with linear actuators.
Years ago I worked on fast circular robots in motor test station.
Was able to get them run with 18.9m/s or 68km/h:
At that point in time I thought that was fast.
Recently I made an outrunner motor run at 36000rpm, with 165.9m/s or 597km/h at cardboard disk edge.
I used much lower speeds to do a multiple exposure with 9us length flashes at 20KHz and created my first 20,000fps video from that. 718km/h will be enough for 100,000fps video:
This week I realized that my Raspberry Pi camera microscope that I claimed to have 153nm/pixel resolution cannot be true, because visible light microscopes cannot go below 200nm resolution:
I learned that the camera allows for 153nm/pixel DISTANCE, resolution needs to be determined.
Later in that thread a 0.01m micrometer scale was easily recorded from Pi camera.
Today I bought a 0.001mm resolution electronic micrometer.
The sort of actuators used in the semiconductor industry are ultra precise and repeatable, but
no doubt well outside your budget - so some indication of budget please too…
And I found a way to do immensely small linear distance changes with 2$(!) 28BYJ-48 stepper motor.
After realizing that my stepper motor has 2048 steps per revolution i did the math.
1st step from 0° position does <=16nm linear distance change!
And even the first 42 steps starting at 0° have all <1um length distance change (less than 22um in total).
Find details here:
Tomorrow I will receive my new 0.001mm electronic micrometer and verify these ultra high precision moves.
(I do need those in order to determine real magnification of Raspberry microscope)
This is overlay of part of 0.01mm micrometer scale over captured laser printer page with dots 0.2mm apart in each direction (same scene, but layers were different, and microscope wheel change was needed to see the one or the other):
The scale does not look nice because of gimp threshholding for alpha blending.
Here you can see 0.7mm of the 1mm in total 0.01mm scale clearly in 5MP photo (right click to zoom):