Openstage: A Low-Cost Motorized Microscope Stage ...

[rjlittlefield]

The following paper was recently called to my attention.

I'm posting the link here because I expect it will be of interest to other members.

--Rik

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3935852/

Openstage: A Low-Cost Motorized Microscope Stage with Sub-Micron Positioning Accuracy
...
Abstract

Recent progress in intracellular calcium sensors and other fluorophores has promoted the widespread adoption of functional optical imaging in the life sciences. Home-built multiphoton microscopes are easy to build, highly customizable, and cost effective. For many imaging applications a 3-axis motorized stage is critical, but commercially available motorization hardware (motorized translators, controller boxes, etc) are often very expensive. Furthermore, the firmware on commercial motor controllers cannot easily be altered and is not usually designed with a microscope stage in mind. Here we describe an open-source motorization solution that is simple to construct, yet far cheaper and more customizable than commercial offerings. The cost of the controller and motorization hardware are under $1000. Hardware costs are kept low by replacing linear actuators with high quality stepper motors. Electronics are assembled from commonly available hobby components, which are easy to work with. Here we describe assembly of the system and quantify the positioning accuracy of all three axes. We obtain positioning repeatability of the order of 1 µm in X/Y and 0.1µm in Z. A hand-held control-pad allows the user to direct stage motion precisely over a wide range of speeds (0.1 to 100 µm/sec), rapidly store and return to different locations, and execute “jumps” of a fixed size. In addition, the system can be controlled from a PC serial port. Our “OpenStage” controller is sufficiently flexible that it could be used to drive other devices, such as micro-manipulators, with minimal modifications.

[TheLostVertex]

This says its name is Openstage, but I do not see any software resources, and only a parts list, which is basically an arduino and a common stepper driver. Have I missed it?

Also it seems like there is no kill switch or support for one. Seems kind of scary to drive something in realtime like they show without positioning info or an out of bounds switch.

[nathanm]

As academic papers go this one is quite practical. I love this quote

"The test slide was made by painting a green patch on a standard slide using a Sharpie accent highlighter. We used the darker, rather than paler green, pen"

Pretty specific if they tell you what color Sharpie to use! While this quote is almost comical, the paper has lots of other small details that would be useful to somebody building a confocal set up like this.

I believe that the "open" in the title refers to "open source hardware"

https://en.wikipedia.org/wiki/Open-source_hardware

This is a radical departure from the very proprietary high end microscope vendors. It is less radical in the context of this forum where many members build complicated electro-optical systems. That said, I haven't seen a DYI confocal system on the forum (but I haven't looked either).

I thought that there was a GitHub link somewhere in the article to software control.

[rjlittlefield]

I don't find a suitable GitHub link in the paper.

But it does mention a source file named OpenStage.ino, and a quick Google search for that found https://github.com/raacampbell/openstag ... /OpenStage .

I was impressed by most aspects of the paper.

However, the paper does leave me very confused about costs. I have written to the first author asking for clarification:

The system described in your paper is very interesting to me, and I have to say that I'm extremely impressed with the high quality and completeness of your work. I seldom see such careful study of a device's actual performance and how it can be improved. Very nicely done!

The reason I'm writing, however, is that I am confused about costs. The paper says that "Our system can be assembled for no more than about $1000". But Table 5 enumerates costs of $471 for components of just the controller unit. The text also says that "Moving the X/Y stage required four pairs of PT1 translators", of which one pair is motorized. Thorlabs' list price for a single PT1 translator is $278 (https://www.thorlabs.com/newgrouppage9. ... 706&pn=PT1). That seems to put the total bill far over $1000 even before adding in the stepper motors, flexible shafts, and miscellaneous hardware to fasten things together.

So, I'm terribly confused.

Have I missed something, or does the $1000 describe the cost of some simpler system, and if so, what system is that?

--Rik

[TheLostVertex]

Thanks Rik, that was what I was looking for.

They say the cost of the translators was 80-150 dollars on the git hub page. I also see most of the sources are 3 years old. Perhaps there has been a price increase in parts they used since this was done?