Agilent VSpin#

The VSpin centrifuge is controlled by the VSpinBackend class.

from pylabrobot.centrifuge import Centrifuge, VSpinBackend
await cf.setup()
cf = Centrifuge(name = "centrifuge", backend = VSpinBackend(device_id="YOUR_FTDI_ID_HERE"), size_x= 1, size_y=1, size_z=1)

You need to calibrate the bucket 1 position for every vspin. You can do that by opening the door (cf.open_door()), manually rotating the buckets to align bucket 1 with the door, and then setting bucket 1 position to the current position with cf.backend.set_bucket_1_position_to_current(). This will save the calibration for the current centrifuge to disk (based on the usb serial number).

await cf.open_door()
# Manually rotate buckets to align bucket 1 with door
await cf.backend.set_bucket_1_position_to_current()

Start spin cycle:

await cf.start_spin_cycle(g = 800, duration = 60)

Going to buckets:

await cf.go_to_bucket1()
await cf.go_to_bucket2()

Loader#

The VSpin can optionally be used with a loader (called Access2). The loader is optional because you can also use a robotic arm like an iSWAP to move a plate directly into the centrifuge.

Here’s how to use the loader:

import asyncio

from pylabrobot.centrifuge import Access2, VSpinBackend
v = VSpinBackend(device_id="YOUR_VSPIN_FTDI_ID_HERE")
centrifuge, loader = Access2(name="name", vspin=v, device_id="YOUR_LOADER_FTDI_ID_HERE")

# initialize the centrifuge and loader in parallel
await asyncio.gather(
  centrifuge.setup(),
  loader.setup()
)

# go to a bucket and open the door before loading
await centrifuge.go_to_bucket1()
await centrifuge.open_door()

# assign a plate to the loader before loading. This can also be done implicitly by for example
# lh.move_plate(plate, loader)
from pylabrobot.resources import Cor_96_wellplate_360ul_Fb
plate = Cor_96_wellplate_360ul_Fb(name="plate")
loader.assign_child_resource(plate)

# load and unload the plate
await loader.load()
await loader.unload()

Installation#

The VSpin centrifuge connects to your system via a COM port. Integrating it with pylabrobot library requires some setup. Follow this guide to get started.

1. Installing libftdi#

macOS#

Install libftdi using Homebrew:

brew install libftdi

Linux#

Debian (rpi) / Ubuntu etc:

sudo apt-get install libftdi-dev

Other distros have similar packages.

Windows#

Find Your Python Directory

To use the necessary FTDI .dll files, you need to locate your Python environment:

  1. Open Python in your terminal:

    python
>>> import sys
>>> sys.executable

  2. This will print a path, e.g., C:\Python39\python.exe.

  3. Navigate to the Scripts folder in the same directory as python.exe.

Download FTDI DLLs

Download the required .dll files from the following link: FTDI Development Kit (link will start download).

  1. Extract the downloaded zip file.

  2. Locate the bin64 folder.

  3. Copy the files named:

    • libftdi1.dll

    • libusb-1.0.dll

Place DLLs in Python Scripts Folder

Paste the copied .dll files into the Scripts folder of your Python environment. This enables Python to communicate with FTDI devices.

Configuring the Driver with Zadig

Use Zadig to replace the default driver of the VSpin device with libusbk:

  1. Identify the VSpin Device

    • Open Zadig.

    • To confirm the VSpin device, disconnect the RS232 port from the centrifuge while monitoring the Zadig device list.

    • The device that disappears is your VSpin, likely titled “USB Serial Converter.”

  2. Replace the Driver

    • Select the identified VSpin device in Zadig.

    • Replace its driver with libusbk.

    • Optionally, rename the device to “VSpin” for easy identification.

Note: If you need to revert to the original driver for tools like the Agilent Centrifuge Config Tool, go to Device Manager and uninstall the libusbk driver. The default driver will reinstall automatically.

2. Finding the FTDI ID#

To interact with the centrifuge programmatically, you need its FTDI device ID. Use the following steps to find it:

  1. Open a terminal and run:

    python -m pylibftdi.examples.list_devices

  2. This will output something like:

    FTDI:USB Serial Converter:FTE0RJ5T

  3. Copy the ID (FTE0RJ5T or your equivalent).

You’re now ready to use your VSpin centrifuge with pylabrobot!