OpenLH: Open Liquid-Handling System for Creative Experimentation With Biology

4,630

45

7

About: We are a Human Computer Interaction lab at the School of Communication, in the Interdisciplinary Center Herzliya, Israel. We design, fabricate and evaluate technology, learning on how we interact with robot...

We are proud to be presenting this work at the International Conference on Tangible, Embedded and Embodied Interaction (TEI 2019). Tempe, Arizona, USA | March 17-20.

All assembly files and guides are available here.

Why did we build this?

Liquid handling robots are robots that can move liquids with high accuracy allowing to conduct high throughput experiments such as large scale screenings, bioprinting and execution of different protocols in molecular microbiology without a human hand, most liquid handling platforms are limited to standard protocols.

The OpenLH is based on an open source robotic arm (uArm Swift Pro) and allows creative exploration. With the decrease in cost of accurate robotic arms we wanted to create a liquid handling robot that will be easy to assemble, made by available components, will be as accurate as gold standard and will cost less than 1000$. In addition the OpenLH is extendable, meaning more features can be added such as a camera for image analysis and real time decision making or setting the arm on a linear actuator for a wider range. In order to control the arm we made a simple blockly interface and a picture to print interface block for bioprinting images.

We wanted to build a tool that would be used by students, bioartists, biohackers and community biology labs around the world.

We hope more innovation can emerge using the OpenLH in low resource settings.

Step 1: Materials

Step 2: The OpenLH Has 3 Main Parts

1. The pipetting end effector.

2. A uArm Swift Pro base

3. A linear actuator operated syringe pump.

* uArm Swift Pro can also be used as a laser engraver, 3d Printer, and more as seen here

Step 3: How to Build the End Effector

1. Dismantle an old pipette and keep just the main shaft.

We used a CAPP ecopipette as it has an aluminum shaft and "O rings" making it air tight. (A-C)

Other pipettes could probably work.

2. 3D Print the parts using PLA and assemble (1-6)

Step 4: Making a Syringe Pump

1. Use a linear actuator Open Builds.

2. Connect 3d printed PLA adapters.

3. Insert a 1 ml syringe .

4. connect the syringe to the end effector with a flexible tube.

Step 5: Setting Up!

Secure all parts to a designated area of work

You can connect the uArm directly to your bench or in your biological hood.

Install python and blockly interfaces:

Python interface #### How to use the python interface? 0. Make sure to do `pip install -r requierments.txt` before starting 1. You can use the library inside pyuf, is our modification for the version 1.0 of the uArm library. 2. For examples you can see some scripts inside the **scripts** folder. #### How to use the printing example? 1. Take a **.png** of the example you would like to print. 2. Run `./convert.sh your_pic.png` and adapt respectevely the path in `test_print.py` to use `your_pic.png.coords` 3. Run `python test_print.py` with the robot connected

### Blockly interface 1. Make sure that you did `pip install -r requierments.txt` before starting. 2. Run `python app.py` this will open the web server that displays the blockly 3. In a different console run `python listener.py` which will be receiving the commands to send to the robot. 4. Now you can use the blockly from the link displayed after running `python app.py`

Step 6: Program Arm With Blockly

Serial dilutions are done by liquid handlers saving time and effort for their human operators.

Using a simple loop to move from different XYZ coordinates and handling liquids with the E variable a simple liquid handling experiment can be programmed and executed by the OpenLH.

Step 7: Print Microorganisms With Pic to Print Block

Using the bit to print block you can upload a picture and have the OpenLH print it.

Define starting point, tip location, bio-ink location and deposition point.

Step 8: Effective Liquid Handling

The OpenLH is surprisingly accurate and has an average error of 0.15 microliter.

Step 9: Some Future Thoughts

1. We hope many people use our tool and conduct experiments they couldn't do otherwise.

So If you do use our system please send your results to info@milab.idc.ac.il

2. We are adding an OpenMV camera for smart colony picking.

3. We are also exploring adding UV for cross linking of polymers.

4. We propose extending the reach with a slider as described by https://www.instructables.com/id/How-to-Combine-UA...

In addition the uArm is extendable by many other sensors that can be useful, if you have ideas let us know !

Hope you enjoyed our first instructable!

The media innovation lab (miLAB) team.

“I make mistakes growing up. I’m not perfect; I’m not a robot.”
— Justin Bieber

Share

    Recommendations

    • Trash to Treasure

      Trash to Treasure
    • Pie Contest

      Pie Contest
    • Build a Tool Contest

      Build a Tool Contest

    7 Discussions

    0
    None
    PeaceOot

    2 months ago

    Isn't there already an air pump in the uArm? Can that be used for the suction needed to transport liquids?

    0
    None
    cosmicaug

    3 months ago

    So what I want to know is where you got a price for this CAPP Ecopipette micropipetter of $65. That's below Dragonlab territory. Elsewhere I'm seeing these for a multiple of that price (and presumably they don't fall apart like Dragonlab does?).

    0
    None
    BasileC

    3 months ago

    Awesome project ! Why not use a full pipette body and actuate the mechanism of the pipette using servos? You could then switch pipettes types easily or clean them.

    2 replies
    0
    None
    cosmicaugBasileC

    Reply 3 months ago

    That's how Opentrons does it. I'm not convinced it's best and it feels like a kludge when seen in person. The way shown may be more flexible.

    0
    None
    miLAB IDCBasileC

    Reply 3 months ago

    Great question! The pneumatic mechanism is less prone to errors than an "electronic thumb" operating a standard pipette. In addition we wanted to make the system take up less space on the bench and so it can be fitted into incubators, hoods and other creative uses. (check Andrew the pipetting robot). On our setup we use tips with filters and the shaft, tube and syringe are easily replaceable in case of a contamination.