About the role

MetroSober builds self-service breathalyser and vending kiosks, which are already running in the field. Each kiosk combines our own PCBs, firmware on an ESP32 and an ATmega328P, and a Raspberry Pi controller.

You will own the kiosk electronics end to end: firmware, sensors, PCB design, and assembling and testing the boards. Your first big task is to move our hardware designs out of Autodesk Fusion 360 into open-source, standard formats.

What you'll do

- Move our designs out of Autodesk Fusion 360 into open, standard formats. This covers:
- Converting the schematics and PCB layouts to KiCad (via Fusion 360's Eagle export and KiCad's importer), then fixing footprints, net classes and copper pours.
- Checking each converted board against the original and against working kiosk hardware.
- Exporting the 3D enclosure to STEP (editable in FreeCAD).
- Producing vendor-neutral fabrication outputs: Gerber + drill files (or IPC-2581), BOM and pick-and-place files.
- Putting all hardware sources under git, with a short README for each board.
- Make and own all PCB changes after the migration, from schematic to layout to fabrication. Work with the fabrication and assembly vendors.
- ESP32 firmware (C/C++, PlatformIO) for the motor and dispense controller. This includes Wi-Fi/HTTP, mDNS and over-the-air (OTA) updates.
- ATmega328P firmware for the breathalyser board, using a JSON protocol over UART.
- Breathalyser sensors: maintain the current semiconductor (MOS) sensor (Figaro TGS2620), and bring up a new electrochemical fuel-cell sensor. That means designing its analog front end, sampling, temperature compensation and calibration.




- Add a new IR / dispense sensor that confirms a product has actually dropped.
- Hand-solder and assemble boards, including SMD rework. Bring them up, test them and debug them.
- Debug how the boards talk to the Raspberry Pi over serial (UART) and Wi-Fi/HTTP.
- Document designs, pin maps, calibration steps and test procedures. Support kiosk installation and field fixes when needed.

Must have At least 1 year prior work experience.

- B.E./B.Tech or Diploma in ECE, EEE, Instrumentation or a related field.
- At least one PCB you designed, had fabricated and assembled yourself. Please share photos, the schematic and the layout. KiCad is preferred; robust work in EasyEDA, Altium or Eagle also counts if you're happy to work in KiCad.
- Hands-on ESP32 or Arduino firmware in C/C++.
- Solid soldering skills, including SMD parts (0603, SOIC, TQFP), and comfort with a multimeter.
- Basic analog electronics: voltage dividers, op-amps, ADC readings and filtering.
- You can debug hardware on a bench without step-by-step supervision.

Nice to have

- Experience moving designs between EDA tools (Eagle or Fusion 360 to KiCad), or managing hardware projects in git.
- FreeCAD, or enclosure work using STEP files.
- Gas or alcohol sensors (MQ-series, Figaro, fuel-cell), or transimpedance amplifiers.
- Debugging with an oscilloscope or logic analyser.
- Motor drivers, IR or optical sensors, demultiplexers.
- Basic Python or Linux (Raspberry Pi).

What you get

- Real ownership in a small team, working directly with the technical lead.
- Paid AI tooling provided by the company.

Pay: ₹15,000.00 - ₹20,000.00 per month

Work Location: In person

📌 Hardware & Firmware Engineer Intern - Bangalore (Bengaluru)
🏢 MetroSober Private
📍 Bengaluru