Minimal manual version of the Openflexure microscope

[WilliamW]

Over on a different thread, the topic of a simplified version of the v7 microscope for manual operation came up. To avoid further thread creep I am starting this new topic on the manual v7.

The microscope is most capable when motorised, and when also using a Raspberry Pi camera so that the white balance and lens shading can be adjusted for the best images. However sometimes motorisation is not needed, and the image quality of a modified simple USB webcam is enough. The standard v7 body is not particularly comfortable for manual operation, and simpler legs can be appropriate when there is no Pi to enclose in the stand.

Because of the quality of the v7 code revisions led by @j.stirling, making a dedicated manual version required remarkably little development. This is not released option, and probably will not make it into the v7.0 release, so only use it if you are happy that there may be problems with the parts and the parts may change without notice. It is available from the merge request number 333, where you can access the parts in the instructions from the view app button. The manual body and simple leg stand are linked from the Customisations and alternatives page, at the bottom. There are no additional instructions, the manual main body is prepared and built into a microscope in the same way as for the motorised versions.

The manual body, printed here in ‘this is a test’ yellow, can sit on the microscope_stand_no_pi.stl for a very stable base.

I have also started on a more simple post mount that is much quicker to print and makes the smallest footprint while still being stable in use.

Printed in ‘this is a test’ yellow again, it makes a very compact overall system.

This is currently in a sub-branch while I work out what to call it. Again there is a view app button to see the built parts. I think the best name would be ‘simple post mount’. The microscope already uses ‘leg’, which refers to the actuator legs of the main stage, and ‘foot’ which refers to the parts at the base of the actuators.

[r.w.bowman]

Nice work @WilliamW, this is very cool. At the risk of feature-creep, I am wondering if your simple post mount might include (1) a way to screw it to the bench/a bit of wood/something heavy, possibly a couple of screw holes just behind the existing screws, and/or (2) something you could loop a cable tie through, to provide a little strain relief on the cable. On the other hand, either or both of those are not too hard for someone to add if they want to…

I think this is fab, definitely something we should include in the future but as you say, possibly not for 7.0.

[WilliamW]

I have already included a cable tie loop on the posts. Strain relief is particularly necessary as the USB cable is connected directly to the moving z-stage for this version of the optics.

There could easily be a screw hole for mounting. My first thought was in the middle of the curved wall, but actually the crook between the posts and the curved wall looks a neat place to put it.

Note: I have now merged the simple stand into the main merge request, so it is now available from there, not from its separate merge request given in the first post.

[WilliamW]

Tidying up I found that I had made provision for a screw point in my local branch, but I had not pushed it to Gitlab. That is now done, so the simple post mount now has mounting points.

There is also now a manual version of the separate z actuator for the Upright version of the microscope.

[biodotpe]

Hi, @WilliamW @r.w.bowman. Will you eventually add the main_body_manual and the simple_post_stand of the V7 manual version to the Customisation section? I just realized these pieces are still missing.

Regarding the assembly instructions, I think having a separate section for the manual version is worth it, particularly for those with an Arducam or Logitech webcam. You can indeed build this version following the standard instructions. However, from an end-user perspective, it’s possible only if you have built the motorized version first or have familiarized yourself with the OpenFlexure instruments. An end-user without previous experience or technical expertise may find the building challenging. @Paola_Larrauri and I would like to work on these instructions because we use the manual version for research and education. In Peru and Chile, this version seems to be the best option as an entry point for end-users and, eventually, the adoption of 3D-printed microscopes in their activities. PS. @nanocastro @pcremades, you are always invited to contribute to the assembly instructions.

Following this reflection, do you have plans on this topic?

[WilliamW]

@biodotpe I am very glad that this version is proving useful. There are two parts of the manual version, the webcam optics and the manual body.

On the optics side, we have re-arranged the customisation section to make all of the options clearer, that is in the v7.0.0-beta3 release that Julian did yesterday. I have made a start on a fuller set of instructions that are in the merge request !311. The view app button from that page should show where we have got to so far.

For the manual body, this sits in the merge request !333. The current plan is that it would be added to the main instructions on a minor release, after the main release of v7.0.0. This is mainly because we still have work to do on sections of the microscope and we want to focus our effort on those to get the main v7.0.0 release out. We also have had some discussions about how we organise the project in the instructions, to make all of the versions available while making it clear that there are some core versions that we will test at each stage, and other versions that do not have so much testing. This will inform where we put the instructions for the manual body, as well as the fluorescence and reflection optics etc.

[biodotpe]

Thank you for your quick response, @WilliamW! With those resources, we will update these instructions using the latest designs, and we will probably implement it using GitBuilding. We will update you once the documentation is complete.

[WilliamW]

@biodotpe, your post prompted me to see what the render system makes of the manual microscope. It all went a bit further than I had originally planned! Merge request !394 now should contain all of the renders needed for a complete set of instructions for the manual microscope. I do still need to correct the positioning of the camera on the renders of installing the illumination and the sample clips the manual. Currently this is with the Pi camera low-cost optics rather than the Logitech C270.

I have also seen that there are a couple of important fixes in the main branch that I should bring over into the manual branch. Particularly there is a better band insertion tool.

Edit 2024-12-08: Merge request !394 now also has a set of instructions built for the manual microscope. This can be accessed from the view app button in the merge request. It is still not based on all improvements in v7.0.0-beta3

[WilliamW]

Update: merge request !333 now has all of the v7.0.0-beta-3 improvements of the main repository, and has complete rendered instructions on the view app button. This has been broken for the last few days from a couple of problems with the updates.

[WilliamW]

The assembly instructions for the manual body are now merged and are available on the current master build. There is also a merge request !311 that has those build instructions, together with instructions for assembling an optics module using the Logitech C270 web cam. Use the view app link and find the alternative optics modules under customisations.
There is more to come with renders of the C270 camera optics assembly.