The idea archive
The course's capstone is now one standardised instrument, but these sixteen vetted project ideas remain a great catalogue of what the dev-board + custom-carrier + AI-software method can build in a few weeks. Browse them for software directions for your instrument (alarms, dashboards, control loops, characterisation methods), for inspiration for what to build next in your own lab β or ask the instructor if you have a strong case for building one of these instead.
Tiers signal risk, not virtue: A = low risk, C = ambitious. All share the same architecture: sensor/actuator β custom carrier β dev board β Python host β web/bot, in a fabricated enclosure.
Tier A β low risk, high polish potential
Cooling-water flow monitor & interlock
Hall-effect flow sensor + ESP32; relay/opto interlock output that fails safe; live plot; bot alert before the magnet cooks. Calibrate with bucket and stopwatch.
Laser beam shutter
Servo or stepper blade on an optical-table mount; TTL (BNC) + serial control; measure open/close time and jitter with a photodiode. Commercial ones cost $500+.
Lab environment logger
Temperature / humidity / pressure nodes on WiFi; database + web dashboard; drift alerts; correlate your laser drift with room temperature.
IP-controlled relay & alarm node
ESP32 with isolated inputs and low-voltage relay outputs controlled from a web page / bot / MQTT; fail-safe defaults, watchdog, authentication, event log.
General-purpose lab amplifier
BNC in/out voltage or instrumentation amplifier with switchable gain, input protection, 50 Ξ© drive, offset trim. The ideal first PCB; measure its bandwidth and noise.
Tier B β real analog, motion or mixed-signal content
Photodetector with variable-gain TIA
Photodiode + transimpedance amplifier with 2β3 gain ranges, bandwidth limiting, on-board ADC streaming, shielded enclosure. Layout quality actually matters here.
PID temperature controller
Thermistor bridge + MOSFET heater or H-bridge TEC driver; digital PID with anti-windup; AI-assisted tuning from logged step responses; overnight mK stability plot.
Motorized filter wheel / rotation mount
Stepper + optical index; homing and indexed positions; printed wheel for Γ25 mm optics β real tolerancing; repeatability measured with a laser.
Arbitrary waveform generator with BNC daughter board
Teensy or ESP32-S3 + external DAC β buffered BNC output; waveform tables uploaded from Python; phone control via a web page the ESP32 serves. Absorbed into the class instrument (the AWG/DAC half).
Precision ADC/DAC front-end
16β24-bit converters, precision reference, anti-alias filters, BNC I/O β measurably better than any microcontroller's built-ins; ENOB measured. The shared hardware for several other projects.
Digitally controlled amplifier / filter
Gain and cutoff set from an ESP32 (digipots, PGA or switched-capacitor filter) β adjustable from your phone; sweep the settings and plot the measured transfer function.
DDS function generator with a real timebase
AD9833-class DDS to 12 MHz driven by the MCU; upgrade the clock with a TCXO or OCXO and add an external 10 MHz reference input; measure the improvement (beat note, Allan deviation). Absorbed into the class instrument (the DDS half).
Digital filter box
ADC β FIR/IIR/notch filters on a Teensy β DAC; coefficients designed in Python (scipy.signal); measure latency and response and compare with design.
Tier C β ambitious
Digital PID "baby lockbox"
Analog error signal in β fast PID on a Teensy β piezo/current out; 10β50 kHz loop; GUI with scope view; minimum demo is locking a simulated plant, a real laser is stretch.
Lock-in amplifier (digital)
Generate the reference, sample the signal, demodulate to X/Y (R/ΞΈ), stream to a host GUI with time-constant controls. Minimum demo: recover a 1 kHz modulated LED signal in room light. Best physics-per-component on the menu.
Multi-channel lab interlock & status hub
Aggregates door / flow / temperature / mains-OK signals into one wall box with relays, status panel, event log, web page and bot; watchdog design; escalation ladder as stretch.
Rejected for good reasons (ask if curious): anything switching mains, robot arms/gantries, wavemeters/spectrometers, high-voltage piezo drivers.