Turning a Bench Prototype into a Self-Running Oil Analyzer

The problem

A research company was developing a compact instrument to track how engine oil changes over time. Oil circulates through a sample loop, a small amount is drawn into a fluidic chip, a spark vaporizes it, and two spectrometers read the light it gives off.

The prototype had all the pieces: pumps, a valve, four pressure sensors, flow and temperature sensors, a spark generator, and two spectrometers. What it needed was hardware to tie them together and software to run them as one machine, safely and without someone at every step, in a package small enough to take into the field.

What we built

The right hardware, kept compact. We helped choose the control hardware: a small NI CompactDAQ chassis with modules for analog, digital, thermocouple, and 24-volt outputs, plus isolated USB and serial connections for the spectrometers and spark generator.

The full measurement cycle, automated. The software checks the inlet pressure, purges the chip with air, fills it with oil and confirms the oil arrived, arms and fires the spark, triggers both spectrometers after a precisely timed delay, and stores the spectra. Then it repeats for as many samples as requested.

Safety that never stops watching. Every pressure sensor and the spark generator’s safety electrode are monitored continuously, each in its own process. If any limit is crossed, the system closes the valve, disarms the spark, and halts, with a clear fault shown on screen.

One sample, or run all day. In manual mode the operator takes each sample on request. In automatic mode the instrument runs continuously until told to stop.

A screen that mirrors the machine. The main view is a live schematic of the instrument, with every pump, valve, and sensor showing its current state, plus status lights for sampling, measuring, waiting, and fault.

A watchdog you can see from across the room. A panel light blinks while the software is healthy. If the software ever freezes, the blinking stops, so a problem is obvious without looking at the screen.

Settings without code changes. Thresholds, timing, and spectrometer and spark settings live on a configuration screen and are saved between sessions. Settings meant only for administrators can be hidden from everyday users with a single switch.

The result

The prototype went from a collection of components run by hand to an instrument that runs its full measurement cycle on its own, stops itself safely when something is wrong, and can be tuned by the researchers as the design matures.