Context & goals

Ensure the shutter meets timing spec under heat and duty-cycle variation while reducing manual effort and producing traceable, repeatable evidence for engineering sign-off.

Requirements / constraints

• Target timing ± tolerance; jitter below threshold

• Thermal range covering expected field conditions

• Repeatable fixture; no changes to the device under test (DUT)

• Automated logging with CSV export and plotted summaries

• Clear pass/fail criteria and full test-matrix coverage

Test architecture (sanitized)

• Instrumented rig: shutter + optical sensor → microcontroller (Arduino (C/C++)) with reference timing

• Thermal loading: controlled heat/soak with temperature logging

• Light control: shroud to block ambient light; fixed distance and angle

• Fixture: rigid mount, tool-less swaps, indexing for consistent alignment

DOE plan

• Factors: temperature, duty cycle, pulse width (optional: supply voltage)

• Responses: actuation latency, jitter, missed events

• Design: randomized order, N replicates per cell, guard runs for warm-up

• Criteria: timing ≤ spec; jitter ≤ limit; 0 missed events

Automation & analysis

• Acquisition: Arduino timestamps with factor levels and run IDs written to CSV

• Pipeline (MATLAB): ingest → QC flags → histograms/CDFs → summary tables

• Plots: latency vs. temperature; jitter distribution; control charts by factor

Results

• Timing met spec across the tested thermal range; jitter below limit in all cells

• Identified a duty setting that minimizes thermal drift

• Generated a one-click report (plots, tables, pass/fail summary)

What I’d improve next

• Add an environmental chamber with controlled ramps and humidity

• Run long-duration endurance with vibration overlay

• Enclose the rig; add a self-check routine and a calibration artifact

• Integrate into CI for nightly regression with alerts