The five-minute problem that costs an afternoon
You sit down to test a sensor, plug in the board, and open the editor — and nothing happens. The port doesn't show up.
Devices & Frontiers / Intermediate
Build Your Own AI Gadget
Build edge-AI projects on cheap hardware: voice boxes, sensors, and smart toys.
The problem
It starts with the situation you're actually in.
Picture a small device next to your keyboard: a microcontroller the size of a stick of gum, a tiny microphone, a couple of jumper wires, and a speaker pulled from an old toy. It cost less than lunch for four people. That's the wager of this book.
You can run a cost canvas and decide whether a project deserves a second unit — but that answers one question about one build. You turn your worksheets into a single forward plan for your next ten projects.
Outcomes
What you'll be able to do.
The light that switched off while you were still in the room
You wire a motion sensor to a desk lamp. Twenty minutes later you're reading, perfectly still, and the room goes dark.
Reliability Is a Budget, Not a Feeling
Your breadboard works. You've shown three people, and each time it did exactly what you promised.
The four ledgers you're actually keeping
A breadboard that works is a story you tell yourself. A bill of materials, a privacy obligation, and a regulatory checklist are stories the world tells back.
Inside the book
A closer look at the work inside.
Reading a voice-box build as a business test
Say you're weighing a self-hosted voice feature — a private assistant assembled from open wake-word, speech-to-text, and local response tools. Treat the build as an experiment, not a craft project, and frame it as a hypothesis: customers will accept a voice interface that runs locally.
Fill in your board-selection scorecard
Do this for one build — the project you named for yourself. Score each criterion from 1 (trivial) to 5 (demanding): memory and compute, where 1 is simple threshold logic and 5 is a trained model running on the board; power, where 1 is wall-powered with run-time irrelevant and 5 is battery-only for days in the field.
Capability is a ladder — climb only as far as the work demands
- Version A — presence light. You want a desk light that turns on when motion is detected and off after a quiet minute. The logic is a threshold.
- Version B — presence logger. Now you want it to log occupancy to a dashboard you check from your phone. Same sensor, but you've added connectivity. Correct board: an ESP32.
- Version C — presence classifier. Now you want it to tell a person from a passing pet using a small vision model running on the device, with no images leaving the room.
Case study: the same idea, three correct answers
Take one project family — "a box that knows when someone is at my desk" — and watch the right board change as the requirement sharpens. This is one build described three ways, not three different ambitions. Version A, presence light: a desk light that turns on when motion is detected and off after a quiet minute.
The "hello sensor" proof
You won't write a useful program here — you'll prove the loop works, which is more valuable. Pick whichever brain you chose. On a microcontroller (Arduino/ESP32), flash the built-in "Blink" example first. If the LED blinks, your compile-and-flash path works, which isolates the toolchain from your wiring.
Build Your Own AI Gadget frameworkInside the book
Visual preview
A diagram you can keep open while you work.
Table of contents
9 chapters, built to be read in order.
01
The Gadget on Your Desk Is a Business Decision
02
Choosing Your Brain — Microcontrollers, SBCs, and the Price Ladder
03
Your Workbench — Tooling, Toolchains, and a Repeatable Setup
04
Build a Private Voice Box
05
Sensors That Sense — Turning the Physical World Into Data
06
Smart Toys and Interactive Objects
07
From Prototype to Product — Reliability, Power, and Enclosures
08
Cost, Risk, and Responsibility — Shipping Without Regret
09
Your Build Roadmap — From This Book to Your Next Ten Projects
180
Pages
13,036
Words
26
Exercises, checklists & tools
9
Chapters
Formats
Three formats. One purchase.
EPUB, PDF, and HTML are included so the book can work on an e-reader, as a designed copy, or as a searchable desk reference.
EPUB
For e-readers and reading apps.
The designed edition with diagrams and layouts intact.
HTML
Searchable, copy-pasteable, and practical as a reference.
Complete guide
Build Your Own AI Gadget
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Intermediate guide pricing
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Before you buy
Questions, answered.
Does this include the full book?
Yes. You get the complete edition, including the chapter sequence and internal materials described on this page.
Which formats are included?
EPUB, PDF, and HTML are included so you can read on an e-reader, keep a designed copy, or use the searchable browser version.
What is the refund policy?
Because this is an instant digital download, broad change-of-mind refunds are not offered after the files have been accessed. Refund requests are reviewed within 7 days for duplicate purchases, accidental purchases before access, access failures we cannot fix, wrong files, corrupted files, or pages that materially misdescribe the book.