Blog

A technical survey of sensing technologies and SLAM algorithms used to build floor plans and 3D models of building interiors. Covers ultrasound, time-of-flight, LiDAR, vision, radar, and inertial methods, with build recommendations for tiny indoor mapping devices.

Roles of GPU, CPU, DPU; CUDA programming model; NVIDIA / AMD Instinct / Intel Gaudi data-center accelerators; AMD Ryzen AI, Intel Core Ultra, Apple Neural Engine, Qualcomm Hexagon client NPUs; Jetson Orin, Coral, Rockchip edge silicon; NVLink generations.

Bringing up the Intel IPU3 CIO2 and ImgU camera pipeline on Debian 12 for a Dell Latitude 7212 Rugged Extreme Tablet. Covers the libcamera plus PipeWire userspace stack that replaces the uvcvideo path, kernel module loading, IPU3 firmware, and verification with v4l2-ctl.

Notes on running a Raspberry Pi 4 Model B as a lightweight ARM homelab node or travel dev machine. Covers the closed-firmware boot chain (bootcode.bin, start4.elf, kernel8.img), config.txt, ZRAM and swap tuning, encrypted boot, remote builds, and ARM container images.

Two topics on batteries. Reading Linux laptop battery state from /sys/class/power_supply and configuring i3status to display current full capacity instead of design capacity. Sizing a battery for a portable radio station based on power draw and duty cycle.