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Title: FlowSense Pro - Industrial Flow & Chemical Dosing SCADA Gateway with OPC-UA & BLE
Problem:
Municipal wastewater treatment plants, breweries, and chemical processing facilities rely on analog 4–20 mA pressure/flow transmitters and mechanical pulse flow meters that lack native network connectivity. Modernizing these field instruments into SCADA platforms historically required dedicated automation racks and programmable logic controllers, inflating per-station deployment costs. Additionally, field technicians in wet, hazardous environments struggle with device commissioning and routine calibration because older systems require physical laptops, terminal blocks, and USB-to-serial cables. Traditional field gateways also lack secure, fail-safe remote firmware updates (OTA), risking operational downtime during software maintenance.
Solution:
Built a ruggedized, DIN-rail mounted smart gateway around the ESP32-S3 (Xtensa dual-core 240MHz) utilizing ESP-IDF v5.x:
High-Precision Dual Measurement: Combines a 16-bit ADS1115 ADC and a 0.1% precision 100 Ω shunt to read 4–20 mA current loops with ±0.5% calibrated accuracy, alongside a hardware pulse counter (PCNT) interrupt engine reading turbine flow meters up to 500 L/min.
Direct SCADA & OPC-UA Integration: Compiles the open-source open62541 OPC-UA stack directly into ESP-IDF, enabling the gateway to communicate natively with SCADA servers and industrial HMIs over TCP/IP without intermediate PLC hardware.
Cable-Free BLE Commissioning: Implements a custom BLE 5.0 GATT profile that allows field operators to calibrate sensor K-factors, set alarm thresholds, and configure local Wi-Fi credentials via an iOS/Android mobile companion app in seconds.
Zero-Power Display & Fail-Safe Actuation: Integrates an ultra-low-power 2.9" SPI E-Paper display that maintains critical process readouts even during brownouts, alongside four opto-isolated 24V/3.5A power MOSFET outputs driving dosing pumps and emergency shutoff valves in <10 ms.
Enterprise Security & Robust OTA: Employs mutual-TLS (mTLS) certificate-based authentication with AWS IoT Core and dual-partition HTTPS OTA with automated bootloader rollback upon boot failure.
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🏢 The Business & The "Greasy Hands" Dilemma:
We built DockFlow (Biscayne Marine OS) for Elena "Rico" Rossi, a solo mobile boat engine mechanic operating "Biscayne Mobile Marine" in Miami, Florida.
Elena drives a mobile workshop van to marinas and canal slips to repair high-performance boat engines (Yamaha, Mercury). But she faced a brutal daily dilemma:
The Greasy Hands Barrier: When working, both of her hands are covered in black engine grease inside noisy boat engine compartments. She physically cannot pick up her phone to answer customer calls.
The Traffic & No-Show Trap: Over 35% of boat owners would cancel after Elena had already driven 45 minutes across Miami bridge traffic in her work van.
Logistics Chaos: Between texting back and forth for marina security gate PINs, boat parking slip numbers, and checking if ocean tides were too shallow to run boat engines, Elena was losing 14+ hours every week just playing phone tag.
⚡ What We Built in Lovable:
We completely rebuilt the moment an inbound customer inquiry turns into a confirmed, paid booking without Elena ever touching her phone:
Marketing Landing Page (/): An executive business homepage with an interactive 3-slide hero carousel explaining the service, problems eliminated, and dockside repair guarantees.
Customer Fast-Track Booking (/book):
Real Microphone Voice Intake: Boaters stranded at a dock don't type long forms. They speak into their phone or record their engine's warning sound using HTML5 microphone capture, and the system extracts their boat specs and symptoms automatically.
Water Depth Safety Check: Verifies Biscayne Bay ocean tide levels (+1.8 ft flood tide) to ensure the water is deep enough to safely lower and test the boat engine without hitting mud.
Smart Neighborhood Routing: Groups appointments by marina cluster (Coconut Grove, Miami Beach) so Elena doesn't crisscross the city.
$175 Deposit Lock: Collects an upfront card deposit to eliminate no-shows.
Self-Service Reschedule & Cancel: Customers can reschedule or cancel in one tap without calling Elena.
Elena's Mission Control (/owner):
Sequential 1-2-3-4 Biscayne Bay route map.
Van Pre-Flight Inventory Matcher: Automatically checks Elena's van shelves (Bin 3B) for replacement cooling parts to guarantee 100% first-time fixes before she drives out.
One-tap status updates ("On the way", "Arrived", "Job Done") that send automated SMS updates to the customer.
Automatically archives completed repairs into a dedicated History & Invoices log.
Realtime Auto-Healing Waitlist Waterfall:
When a boater cancels last minute, a Supabase Realtime broadcast triggers an instant 5-minute countdown alert to the next standby boater in line (Capt. Marcus Vance), auto-filling the vacant spot with zero manual texting!
Miami Localization & Enterprise Polish:
Fully bilingual in English and Spanish (over 60% of South Florida boaters speak Spanish).
Light and Dark mode themes.
Powered by a scalable Supabase database backend.
📈 Measurable ROI:
⏱️ 14 Hours Saved Weekly in manual scheduling and phone tag.
🛡️ Zero No-Shows thanks to upfront card deposits.
🚗 2+ Hours Saved Daily in Miami bridge traffic via neighborhood clustering.
🔧 No Wasted Parts Runs with van inventory pre-flight matching.
Live App: https://dockflow-biscayne.lovable.app/
lovablechallengeFull Stack DevelopmentLow-Code/No-Code DevelopmentWeb DevelopmentLovableNext.jsSupabase
Amazing! Love the backstory and a female boat mechanic with greasy hands. Well done.
What actually shipped across every client this month:
A lead qualification bot, an inbox triage system, a contract automation flow, and a hiring screen different clients, same principle: automate the repetitive part, keep a human on anything that needs judgment.
→ Happy to walk through any of these in more detail.
Seeing the lead qualification bot take the first pass on prospects really frees up the team for deeper conversations. The inbox triage does the same for support tickets, letting agents focus on the tricky cases.
Many customers, especially older people, do not understand plumbing problems and find it hard to explain what is wrong over the phone. To solve this, I built a simple solution where the customer just takes a picture of the problem. The AI looks at the picture and automatically understands the situation. Then, based on what it sees, the website asks a few simple yes-or-no questions to learn more. Using the picture and the answers, the website automatically decides if the problem is urgent, medium, or low urgency. If the AI cannot clearly understand the picture, the customer can also choose the problem manually from a list of options. After this, the customer picks a time slot and chooses between an urgent visit or a normal visit, then fills in their address and contact details to complete the booking. The customer only pays after the work is finished, and if extra parts are needed, they can also see and approve the extra cost for those parts. On the owner's side, every booking shows an urgency badge, so the owner immediately knows which job is more important and which can wait. The owner also has a "close bookings" option, which turns off all bookings and time slots instantly, useful during emergencies or personal time off — and the owner's phone number is always shown on the website in case someone needs urgent help. Another feature on the owner's side is an arrival progress bar, so the customer can see how far the plumber is, while the owner can update the route and arrival status.
Walkthrough video link : https://app.trupeer.ai/view/wIl0JY0BD/plumbing-booking-system
Nicely understood the problem!