Skip to content

Hardware

Zlatko Lakisic edited this page Aug 3, 2026 · 1 revision

Hardware

Hardware bill of materials


Bill of materials

Component Part Notes
Terminal Raspberry Pi 4 (4GB+) 8GB recommended if rendering a heavy avatar locally
Camera Logitech USB webcam (e.g. C525) Any UVC camera; used for vision only
Microphone ReSpeaker 2-Mic / 4-Mic array or USB conference puck Strongly recommended over the webcam mic
Display Small HDMI panel 800×480 to 1280×720 (bring-up used 1024×768)
Audio out USB or 3.5mm powered speakers / HDMI Kiosk plays TTS via Chromium (ADR 0001)
Brain AI server with NVIDIA RTX 4000 Ada AO + CodeProject.AI; preferred speech sidecars
Network Wired ethernet to the Pi Wi-Fi adds jitter to the frame stream

On the microphone

The webcam's built-in mic is the weakest link in the entire build. Those capsules are tuned for a face ~40 cm away. At 2–3 m across a room with any reverb, wake-word accuracy falls off a cliff.

A beamforming array will do more for the felt quality of this project than any other single upgrade. Keep the webcam for vision; add a separate mic for audio.

Mic distance problem


Observed bring-up board

Documented in Baselines:

Field Value
Board Raspberry Pi 4 Model B Rev 1.5, 4 GB
Hostname comstar-ai
OS Debian 12 Bookworm, kernel 6.12.x
Camera Logitech HD Webcam C525 (/dev/video0)
Mic (bring-up) C525 built-in — adequate close-range; room UAT open
Display HDMI-A-1 1024×768@60
Ethernet Preferred default route

AI server services

Service Port Role
CodeProject.AI 32168 YOLO detect + face recognize
agentic-orchestration 8765 Planner, sessions, overlays, MCP
Speech STT sidecar 8090 faster-whisper (preferred when advertised)
Speech TTS sidecar 8091 Piper (preferred when advertised)

AI server rack diagram


Related pages

Clone this wiki locally