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We’ve seen a lot of practical machines built using Lego. Why not? The bricks are cheap and plentiful, so if they can get the job done, who cares if they look like a child’s toy? Apparently, not [Yuksel Temiz]. He’s an engineer for IBM whose job involves taking pictures of microscopic fluidic circuits. When he wasn’t satisfied with the high-power $10,000 microscopes he had, he built his own. Using Lego. How are the pictures? Good enough to appear in many scientific journals.

Clearly, the microscope doesn’t just contain Lego, but it still came in at under $300. According to an interview from Futurism, the target devices are reflective which makes photographing them straight-on difficult. After experimenting with cameras on tripods, [Yuksel] decided he could build his own specialized device. You can see a video of the devices in question and some of the photographs below.

According to the same interview, it took several prototypes to get it right. The first prototype didn’t use Lego but was 3D printed. However, in a quest to make the microscope more modular and configurable, [Yuksel] raided the toy box.

The open source microscope is fully motorized, modular, and uses a Raspberry Pi with an 8-megapixel camera to capture images. An Arduino controls stepper motors and the lighting. The second video, below, shows the construction, and you can find documentation on IBM’s GitHub repository.

Not that we haven’t seen custom microscope builds before. If you prefer 3D printing, this might get you started.

[JBumstead] didn’t want an ordinary microscope. He wanted one that would show the big picture, and not just in a euphemistic sense, either. The problem though is one of resolution. The higher the resolution in an image — typically — the narrower the field of view given the same optics, which makes sense, right? The more you zoom in, the less area you can see. His solution was to create a microscope using a conventional camera and building a motion stage that would capture multiple high-resolution photographs. Then the multiple photos are stitched together into a single image. This allows his microscope to take a picture of a 90x60mm area with a resolution of about 15 μm. In theory, the resolution might be as good as 2 μm, but it is hard to measure the resolution accurately at that scale.

As an Arduino project, this isn’t that difficult. It’s akin to a plotter or an XY table for a 3D printer — just some stepper motors and linear motion hardware. However, the base needs to be very stable. We learned a lot about the optics side, though.

Two Nikon lenses and an aperture stop made from black posterboard formed a credible 3X magnification element. We also learned about numerical aperture and its relationship to depth of field.

One place the project could improve is in the software department. Once you’ve taken a slew of images, they need to blend together. It can be done manually, of course, but that’s no fun. There’s also a MATLAB script that attempts to automatically stitch the images together, blending the edges together. According to the author, the code needs some work to be totally reliable. There are also off-the-shelf stitching solutions, which might work better.

We’ve seen similar setups for imaging different things. We’ve even seen it applied to a vintage microscope.

At the risk of putting too fine a point on it, Hackaday exists because people are out there building and documenting open source gadgets. If the person who built a particular gizmo is willing to show the world how they did it, consider us interested. Since you’re reading this, we’ll assume you are as well. Over the years, this mentality has been spreading out from the relatively niche hacker community into the greater engineering world, and we couldn’t be happier.

Case in point, the Poseidon project created at the California Institute of Technology. Developed by students [Sina Booeshaghi], [Eduardo Beltrame], and [Dylan Bannon], along with researcher [Jase Gehring] and professor [Lior Pachter], Poseidon consists of an open source digital microscope and syringe pump which can be used for microfluidics experiments. The system is not only much cheaper than commercial offerings, but is free from the draconian modification and usage restrictions that such hardware often comes with.

Of course, one could argue that major labs have sufficient funding to purchase this kind of gear without having to take the DIY route. That’s true enough, but what benefit is there to limiting such equipment to only the established institutions? As in any other field, making the tools available to a wider array of individuals (from professionals to hobbyists alike) can only serve to accelerate progress and move the state of the art forward.

The Poseidon microscope consists of a Raspberry Pi, touch screen module, and commercially available digital microscope housed in a 3D printed stage. This device offers a large and clear view of the object under the microscope, and by itself makes an excellent educational tool. But when running the provided Python software, it doubles as a controller for the syringe pumps which make up the other half of the Poseidon system.

Almost entirely 3D printed, the pumps use commonly available components such as NEMA 17 stepper motors, linear bearings, and threaded rods to move the plunger on a syringe held in the integrated clamp. Controlled by an Arduino and CNC shield, these pumps are able to deliver extremely precise amounts of liquid which is critical for operations such as Single-cell RNA sequencing. All told a three pump system can be built for less than $400 USD, compared to the tens of thousands one might pay for commercially available alternatives.

The Poseidon project joins a relatively small, but very exciting, list of DIY biology projects that we’ve seen over the years. From the impressive open source CO2 incubator we saw a few years ago to the quick and dirty device for performing polymerase chain reaction experiments, there’s little doubt about it: biohacking is slowly becoming a reality.

Set
25

Building a Low-Cost Nanoscope with Lego and Makeblock

arduino, Imaging, LEGO, Makeblock, Maker Faire, microscope, science Commenti disabilitati su Building a Low-Cost Nanoscope with Lego and Makeblock 

lego-toolsStudents at a workshop built a sub-$500 atomic force microcope out of Lego, Makeblock, 3D-printed parts, and Arduinos.

Read more on MAKE

Mar
28

DIY soil moisture sensors

arduino, Electronics, microscope, Sensor Commenti disabilitati su DIY soil moisture sensors 

I’ve been looking into creating an automated herbarium of some sort for a while, and I came across the brilliant post about creating some DIY soil moisture sensors using nails and plaster of paris. cheapvegetablegardener from hackaday.

Plaster of paris humidity sensor

Plaster of paris humidity sensor


Plaster of paris humidity sensor with wires attached

Plaster of paris humidity sensor with wires attached


Both of the sensors

Both of the sensors

I wont explain all of the theory or background as it is already explained on cheapvegetablegardener.

Resistance experiment on moisture sensor

Resistance experiment on moisture sensor

I measured the resistance of the sensor in air to be 12Kohms, I then placed the sensor into water (keeping the nail heads above the surface). The resistance dropped to 4Kohms whilst in the water, and then over 20 mins of back in air the resistance rose to 5.6Kohms. The sample still looks and feels quite wet, so I imagine it is going to take some time to dry, but from these prelimary results we can see it appears to work.

Soldering the wires to the nails before creating the plaster of paris along with covering the end sensor with hot glue would improve its longevity. I will post again once I find a better mould to make the plaster in as it was quite difficult to get them out of the cuvettes (I had about a 50% success rate).

Here is a microscope image of the surface of the plaster:

Microscope image of the surface of the plaster of paris

Microscope image of the surface of the plaster of paris



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