Exploring an alternative to traditional PLC-based architecture for a photometric test system using an integrated DAQ platform
We’ve been working on a compact industrial DAQ/control platform for one of our photometric test systems, and recently started exploring it as an alternative to parts of a traditional PLC-based setup.
In this type of system, the controller reads data from light sensors while positioning the light source with motors during the measurement process. The setup combines analog measurement, PID control, motion control, and communication in a single workflow.
The original architecture required multiple separate modules for:
• Analog measurement
• PID control
• Motion control
• Communication
Over time, wiring and integration became more complex than the actual control problem.
We also wanted more flexibility for custom signal processing and motion integration than we were getting from the existing setup.
So we started building a more integrated approach around:
• Differential analog I/O
• Built-in PID control
• PWM / Pulse-Direction motion outputs
• Isolated USB and RS485 communication
• Separate analog and digital power domains
The current hardware includes:
• Differential analog inputs (up to 30 kS/s)
• Analog outputs capable of directly driving up to 250 mA per channel
• 16 digital inputs and 12 high-side digital outputs
• Integrated motion-control outputs for drivers and actuators
• Galvanically isolated analog measurement section (~1.5 kV isolation)
• Isolated communication interfaces rated for several kilovolts
• 24 V industrial power architecture
These systems are often deployed in electrically noisy industrial environments with long cable runs, switching supplies, sensors, and motor drivers nearby, so maintaining stable measurement and control behavior became a major part of the design.
We’re curious how people here approach similar systems today:
Would you still prefer a traditional PLC architecture for this type of application, or move toward more integrated embedded control platforms?
For anyone interested in the implementation details, we also posted a short prototype demo and a more detailed project log here:
• YouTube demo: https://youtu.be/IFupzC8g6V8?si=dQOxar2g1X-wtbte
• Pre-launch page: https://www.crowdsupply.com/noora-lab-tech/noora-industrial-daq