Project Overview
Uvach AI Systems LLP engaged FoogleTech Software to design, develop, and validate a voice-first wearable AI assistant device from the ground up. The engagement covered the full stack: firmware architecture on the Quectel EC200U LTE modem, AI backend integration via push-to-talk audio pipeline, Bluetooth HFP/A2DP headset support, GNSS positioning, silent duress mode, enterprise-grade security hardening, and custom PCB design — all delivered across a structured 5-milestone, 15-week engagement. The device supports hands-free voice calls, SMS, multilingual AI Q&A, and a covert emergency trigger with GPS location reporting.
The Engineering Challenge
- No existing firmware foundation — the entire stack had to be designed from scratch on the Quectel EC200U LTE modem, including AT command interface, AWB audio pipeline, multi-stack connectivity, button/LED/vibration control, and power management.
- Push-to-talk latency was a core UX requirement: audio capture, AWB compression, HTTPS upload to the AI backend, server-side speech recognition and AI processing, and audio response playback all needed to complete within a user-perceivable window — with no buffering or delay artefacts.
- Five independent communication stacks — LTE voice calls, SMS, Bluetooth HFP/A2DP headset, GNSS location, and cloud MQTTS telemetry — had to operate simultaneously on constrained hardware without any stack blocking or degrading another.
- A strict firmware-first strategy meant custom PCB design could not begin until all firmware features were formally signed off, compressing the entire hardware design, layout, fabrication, and bring-up phase into just 4 weeks.
- Enterprise-grade security was non-negotiable: TLS 1.3 with mutual authentication, secure boot with rollback protection, per-device X.509 certificate provisioning, and signed OTA updates with integrity validation — all implemented on a constrained embedded MCU with limited secure storage.
Our Solution
- FoogleTech deployed a 4-person cross-functional team — embedded firmware engineer, hardware engineer, PCB layout engineer, and QA — structured across 5 formal milestone phases with signed acceptance gates between each phase, eliminating scope drift and ensuring commercial clarity at every handoff.
- We leveraged the EC200U modem's native AWB codec support to build a zero-overhead audio pipeline: push-to-talk capture triggers AWB compression natively on the modem, the compressed file is uploaded via HTTPS, the backend AI response arrives as AWB audio, and playback runs on the same modem codec — achieving end-to-end AI response under 3 seconds on LTE.
- A modular RTOS-style firmware architecture was designed with isolated task contexts for telephony, audio, Bluetooth, GNSS, and cloud connectivity — each with its own event queue and error recovery logic, ensuring all five stacks ran concurrently without blocking.
- Silent duress mode was implemented using a predefined button combination that transmits GPS coordinates and a timestamp to the backend over MQTTS — with zero audio, LED, or vibration output during the entire emergency sequence, ensuring covert operation in hostile situations.
- After formal firmware sign-off at Week 11, FoogleTech designed custom schematics and PCB layout with RF, antenna, audio, and power placement optimised for the wearable form factor. Gerber files, final BOM, and manufacturing documentation were delivered at Week 14. Two fully assembled prototype boards were brought up, validated across audio, RF, power, and thermal parameters, and handed over at Week 15.
Results & Outcomes
- All 5 user journeys — voice calls, SMS, AI push-to-talk Q&A, Bluetooth headset, and silent duress mode — validated and formally signed off within the 15-week engagement timeline.
- Secure OTA firmware update framework delivered with rollback protection and integrity validation — production devices can be updated remotely with zero risk of bricking in the field.
- Custom PCB designed, fabricated, brought up, and validated within 4 weeks — 2 fully assembled prototype boards with complete audio, RF, power, and thermal sign-off delivered for manufacturing handover.
- Zero critical security findings on the final security validation and penetration testing report — TLS 1.3 mutual authentication, secure boot, and per-device certificate provisioning all implemented and verified.
- Firmware-first strategy validated: by completing full firmware sign-off before committing to hardware tooling, Uvach AI Systems avoided an estimated 3–4 weeks of PCB re-spin risk and protected their hardware investment.
Why Uvach AI Systems LLP Chose FoogleTech Software
FoogleTech Software is a specialist engineering company with over a decade of expertise in AI, embedded systems, IoT, and full-stack software development — serving product teams and enterprises across Smart Home & Consumer Electronics and beyond. Our engineers don't just write code — they understand the domain, the constraints, and the real-world pressures that ship deadlines create. For Uvach AI Systems LLP, that meant deploying a pre-vetted team with direct experience in EC200U LTE Modem, Embedded C, Bluetooth HFP/A2DP, reducing ramp-up time from months to days and delivering production-quality work from the first sprint.
Every FoogleTech engagement starts with a structured discovery phase, follows a disciplined agile delivery model with daily engineering syncs, and ends with complete documentation handover — so your in-house team owns the outcome. No black boxes, no lock-in.