Please, I am working on the OpenFlexure microscope. After assembling it, I successfully completed the calibration (auto) for the lens. However, when I try to calibrate the motors for the stage, I keep getting a warning that says, “The motors moved 23234 but saw no motion.” After that, the calibration ends, and I am unable to achieve high focus.
check vids and pics here Openflexure Microscope - Google Drive
Could anyone help me fix this? I’m stuck on this issue
Hi @Mohammed_1, which version of the microscope have you built?
Have you got a microscope slide on the microscope for the stage calibration, and can you see the sample on the camera?
Lastly, do the motor gears move when you are expecting the stage to move?
@WilliamW thank you for responding to this ,
The version is v7. Yes, I have used slides, and I can see the camera feed and visuals of the slides. The gears move, and you can even see the image shifting.
here some videos of the errors Link Openflexure Microscope - Google Drive
Hi @Mohammed_1, looking at your photo I can see a blue band on the objective. Would I be right in thinking this is a 40x or 60x objective? These can be a little tricky to get focused from my experience, at least initially. Firstly I would try placing your slide upside down as it might be the sample is sitting outside the focal range. Higher magnification objectives are a little unforgiving when it comes to focal range.
If flipping the slide doesn’t work maybe try a lower magnification objective if you have one and seeing if you can get that in focus first.
The “saw no motion” error can happen if the microscope is struggling to focus on the slide which I think is your issue.
Thank you for the pictures. @malkanicus is right, the most likely issue is that you have the slide the wrong way up. The focal length of a 40x microscope objective is very short, and the working distance from the lens to the object is much less than 1mm. This means that you need the sample on the same side as the objective, which is underneath. With the z-axis physically centred (the nut slot on the z-actuator inner column aligned with the slot in its casing) the top of the objective should be close to the slide, but not touching. In that position you should be fairly close to focus, although it may still take a bit of trial to find focus the first time.
Once you have a reasonably focused image the camera stage mapping should work.
Firstly it would be a good idea at this point to put the stage back towards a central position. The easiest way to do that is often to unscrew the motors and rotate the large gears by hand. You want the nut holes in the outer shell of the actuators to match up with the slots in the inner actuator columns for all three actuators. You may also be able to see or feel any underlying mechanical problems with the atage when doing this - does the stage move smoothly and does the optics module move up and down smoothly? Then reattach the motors.
Exit the failed calibration and go to the navigate screen. As you have physically set the stage to the mid point, use the zero coordinates button to tell the stage that this is the middle.
Still in the Navigate tab, under configure set the step size to 1000 steps for each axis. Then could you let us know what happens when you try these moves:
1 Press the right arrow on the keyboard, then the left arrow. The x- motor should turn 1/4 turn of the small gear and you should see the image move sideways back and forth.
2 Press the up arrow on the keyboard, then the down arrow. The y- motor should turn 1/4 turn of the small gear and you should see the image move up and down.
1 Press page up on the keyboard, then page down. The z- motor should turn 1/4 turn of the small gear. You cannot directly see that gear, the large gear will turn 1/8 turn each way. The focus of the image should change, it may not change much if you are slready far from focus.
Thank you, I will try this and get back to you on whatever I observed.
@WilliamW @Mohammed_1 I am able to build the openFlexure microscope, but at the point of Auto-calibration, it gives this error [notification] “Array must not contain infs or nans”
What is the solution to this error please?
Welcome @princeedison, that is a bit of a strange error. You should be able to exit the calibration stage without calibrating. In your post you show what looks to be a reasonably focused image of a sample. Does the stage and optics move as expected if you try the moves that I suggested for @Mohammed_1 [edited the wrong user tag] in post 7 here, using the navigate pane?
If the stage is moving as expected, then try the camera stage mapping calibration again, which is in the settings pane under camera stage mapping.
