QInstrument 2.2.0

Qt-based framework for controlling scientific instruments over serial ports

QInstrument

A Qt-based framework for controlling scientific instruments over serial ports. Instruments are represented as Qt objects with a uniform property system, automatic UI binding, and JSON-based configuration persistence. Any Qt binding (PyQt5, PyQt6, PySide2, PySide6) is supported via qtpy.

Instruments

IPG Photonics

• YLR Series: Ytterbium fiber laser

Laser Quantum

• Opus: Continuous-wave laser

PiezoDrive

• PDUS210: Piezo transducer driver

Prior Scientific

• Proscan II/III: Motorized microscope stage controller

Stanford Research Systems

• DS345: 30 MHz Synthesized Function Generator
• SR830: 100 kHz Digital Lock-in Amplifier
• SR844: 200 MHz RF Lock-in Amplifier

Tektronix

• TDS1000: Digital oscilloscope

Installation

pip install QInstrument
pip install PyQt6          # or PyQt5, PySide2, PySide6

Installing from PyPI also places a qinstrument command on your PATH.

To install from source:

git clone https://github.com/davidgrier/QInstrument
cd QInstrument
python -m venv .qi
source .qi/bin/activate
pip install -e ".[dev]"

Quick start

Rack application

Launch the rack to control multiple instruments at once:

qinstrument DS345 SR830

On subsequent runs, qinstrument with no arguments restores the last-used instrument list automatically. Use the Add instrument… button to add instruments at runtime, or right-click any instrument to remove it.

Single instrument widget

Each instrument widget also has a built-in example() entry point:

python -m QInstrument.instruments.DS345.widget

This finds a connected DS345 and opens its control panel. If no instrument is detected it falls back automatically to a simulated (fake) device so the UI is always usable.

Embedding a widget in your application

from qtpy.QtWidgets import QApplication
from QInstrument.instruments.DS345 import QDS345Widget

app = QApplication([])
widget = QDS345Widget()
widget.show()
app.exec()

Using a simulated instrument

When hardware is not available, pass a fake device directly:

from QInstrument.instruments.DS345 import QDS345Widget, QFakeDS345

app = QApplication([])
widget = QDS345Widget(device=QFakeDS345())
widget.show()
app.exec()

Architecture

QtCore.QObject
└── QAbstractInstrument      # property/method registry, thread-safe get/set
    └── QSerialInstrument    # holds QSerialInterface; adds open/find/identify
        └── QXxxInstrument   # concrete instrument

QtSerialPort.QSerialPort
└── QSerialInterface         # raw serial I/O (owned by QSerialInstrument)

QWidget
├── QInstrumentWidget        # loads .ui file; auto-binds widgets to properties;
│                            # saves/restores device state via Configure
└── QInstrumentRack          # holds multiple QInstrumentWidgets; runtime
                             # add/remove; saves/restores instrument list

Each instrument lives in instruments/<Name>/ with three files:

File	Purpose
instrument.py	Serial communication and property registration
fake.py	Simulated instrument for UI development without hardware
widget.py	Qt widget, .ui file binding, example() entry point

Development

Run the test suite:

source .qi/bin/activate
pytest tests/

Tests run automatically before every git push via a pre-push hook. To install the hook in a fresh clone:

cp hooks/pre-push .git/hooks/pre-push   # if tracked, else set up manually
chmod +x .git/hooks/pre-push

Acknowledgements

Work on this project at New York University is supported by the National Science Foundation of the United States under award number DMR-2438983.