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GenAI Kids · Fall 2026 Class 01 / 08
Player 1 start

Meet the
Robots

How real robots sense, think, learn, and wiggle — then a tour of Reachy Mini, our desktop teammate.

Reachy Mini sitting on a desk next to a laptop
Reachy Mini — a real robot on a real desk. That's ours.
Today's quest

Two worlds. One class.

01

The robot kingdom

  • Sensors — a robot's eyes, ears, and balance
  • Brain — the computer that decides
  • Learning — practice vs. following a recipe
  • DOF — door 1, neck 3, Reachy 9
02

Meet Reachy Mini

  • Its camera, mics, speaker — real parts photos
  • Its brain — Raspberry Pi or your laptop
  • Its 9 motors and Stewart-platform head
  • Safety, naming ceremony, first behavior
Robot zoo · 1 / 8

Roomba

iRobot Roomba vacuum robot
Home helper · cleans floors by itself

A disc that lives under the couch — and it's still a real robot.

  • Bumper = touch sensor
  • Tiny computer = brain
  • Brushes & wheels = act
Robot zoo · 2 / 8

Spot

Boston Dynamics Spot four-legged robot
Four legs · walks like a metal dog

Not a cartoon. This robot walks over rocks, stairs, and factory floors.

  • Cameras on its face
  • Legs instead of wheels
  • Boston Dynamics
Robot zoo · 3 / 8

Factory arms

Industrial robots building car bodies in a factory
Car builders · weld and lift all day

They don't chat. They don't walk. They still count as robots.

  • Many arms, one car
  • Repeat the same move
  • Super strong
Robot zoo · 4 / 8

Curiosity

NASA Curiosity rover self-portrait on Mars
Mars explorer · NASA / JPL-Caltech

A robot the size of a car — taking a selfie on another planet.

  • 17 cameras to see Mars
  • Arm camera took this photo
  • Driven from Earth
Robot zoo · 5 / 8

Pepper

SoftBank Pepper social robot
Talks & listens · a robot for people

Not every robot is a metal arm. Some are built to chat.

  • Big camera eyes
  • Microphones to hear you
  • Tablet on its chest
Robot zoo · 6 / 8

Canadarm2

Astronaut on the Canadarm2 robotic arm in space
Space arm · moves astronauts above Earth

A robot so big an astronaut can stand on it.

  • Lives on the space station
  • Giant joints = lots of DOF
  • Human + robot teammates
Robot zoo · 7 / 8

Atlas

Boston Dynamics Atlas humanoid robot
Humanoid athlete · jumps, flips, parks boxes

This one DOES look like a person — on purpose.

  • Cameras in its head
  • Two arms, two legs
  • Practiced until it could jump
Robot zoo · 8 / 8

da Vinci

da Vinci surgical robot in an operating room
Hospital helper · tiny tools for surgeons

Four skinny arms. A human doctor is still the boss.

  • Works in an operating room
  • Super-precise wrists
  • Robot + human team
The magic loop

Every robot does three things

Pepper robot looking and listening with camera eyes and microphones
1. Sense · cameras, mics, balance chips
Raspberry Pi 4 single-board computer
2. Think · a computer brain
KUKA industrial robot arm in motion
3. Act · motors, wheels, voice
If it can't sense, think, AND act, it's a toaster — not a robot. A washing machine is close. Reachy Mini is the real deal.
World 1 · insert coin

How robots
work

Sensors · Brain · Learning · DOF

Sensors

Sensors are a robot's senses

Eyes
Cameras
Ears
Microphones
Balance
IMU chip
Extra
Lidar · GPS
DJI Phantom camera drone flying with its gimbal camera pointing forward
Flying camera · a drone's eye
Studio microphone
Microphone · a robot ear
Accelerometer IMU sensor chip
IMU · knows tilt & shake
Car with roof sensors for hands-free driving
Car sensors · see the road
Eyes

Cameras let robots see

Curiosity rover selfie on Mars taken with arm camera
Mars selfie. Curiosity used a camera on its ARM — 17 cameras total.
NASA Perseverance rover selfie on Mars
Perseverance · another Mars eye
Tesla Model 3 with cameras that see the road
Tesla · cameras on Earth see the road
Ears

Microphones let robots hear

Pepper robot designed to talk with people
Pepper listens, then talks back
NAO humanoid robot
NAO · classroom talking robot
Spherical microphone array
Mic array · many ears, finds direction
Kid secret: 4 microphones can tell if you clapped on the left or the right. Reachy Mini has exactly that.
More senses

Balance, maps, and “don't fall”

Boston Dynamics Spot Mini robot
Spot feels every step
Robot vacuum with lidar navigation tower
Lidar tower maps the room
MEMS accelerometer chip
IMU chip · tilt & shake
Honda ASIMO walking humanoid robot
ASIMO · walking takes sensors
Brain

The brain is a computer

Raspberry Pi 4 computer
Raspberry Pi · pocket-size brain
Computer motherboard with CPU fan
Laptop board · a bigger brain
Self-driving car packed with computers
Car computer · thinks while driving
Canadarm2 operated from mission control and space
Space arm · brain on Earth + ISS
The brain's job is boring and amazing: read sensors → decide → tell motors what to do — many times per second.
Learning

How does a robot get smarter?

Recipe robots

Humans write every step. “If the bumper hits, turn left.” Great for doors. Bad for messy worlds.

Learning robots

They practice on lots of examples — photos, games, rooms — until patterns stick. That's AI.

Robot vacuum that maps a home
Maps a house by rolling around
Waymo learning to drive in a city
Learns streets from miles of driving
IBM Deep Blue chess computer
Deep Blue beat a chess champion
Atlas robot that learned athletic motion
Atlas practiced jumps & steps
DOF

One independent way to move

Kid-friendly DOF graphic: a door has 1 DOF, a neck has 3 DOF, Reachy Mini has 9 DOF
1 door · 3 neck (nod, shake, tilt) · 9 Reachy Mini
Try it

Your neck is 3 DOF. Go!

1 · pitch
NOD

yes / looking down

2 · yaw
SHAKE

no / look left & right

3 · roll
TILT

ear toward shoulder

Reachy Mini's head can do those 3 — plus it can slide, spin its body, and wiggle two antennas. That's how you get to 9.
Real robots

How many DOF out in the world?

6 Collaborative factory robot arm
Factory arm · 6 DOF · put a tool anywhere
9 Reachy Mini on a desk
Reachy Mini · 9 DOF · that's ours
12 Boston Dynamics Spot quadruped robot
Spot · 12 DOF · 3 per leg × 4 legs
20 SoftBank Pepper social robot
Pepper · ~20 DOF · talks with people
28+11 Tesla Optimus humanoid robot standing among people
Tesla Optimus · ~28 body + 11 per hand
57 Honda ASIMO walking humanoid robot
Honda ASIMO · 57 DOF · famous walker
Zoom in
Tesla Optimus Gen 2 among people at an event
Tesla Optimus · human-sized · walks on two legs

Why Optimus has so many

~28
Body DOF · walk, bend, twist like a person
11 × 2
Each hand · fingers that can pick up an egg

A factory arm needs 6 to place a tool. A walking humanoid needs dozens because legs + waist + neck + fingers all count.

Reachy Mini stays at 9 on purpose — a desktop face, not a walking worker.

World 2 · boss level

Meet
Reachy Mini

Hugging Face × Pollen Robotics · open source

The teammate
Assembled Reachy Mini on a wooden desk
Real Reachy Mini · about as tall as a water bottle

A desktop robot with feelings (almost)

  • Built by Hugging Face and Pollen Robotics
  • ~28 cm tall · ~1.5 kg · sits beside your laptop
  • 9 motors for a curious head, spinning body, wiggly antennas
  • 100% open source — we can see every part
9
Degrees of freedom
4
Microphones
Two versions · same body

Where does the brain live?

Reachy Mini Lite

Your Mac / PC is the brain. USB cable. Same dance moves.

Reachy Mini dimensions diagram
About 27.5 cm to the head · antennas extra

Reachy Mini Wireless

A Raspberry Pi CM4 lives inside. Wi-Fi + battery. Thinks on its own.

Raspberry Pi computer like the CM4 brain
Family of the onboard computer
Reachy senses

Eyes, ears, voice, balance

Reachy Mini with callouts for microphone array and camera
Official parts map · camera + 4-mic array
  • Camera — Raspberry Pi Camera v3 wide, 12 MP, 120°, autofocus. That's the eye.
  • 4 microphones — a tiny array on top of the head. Finds voices.
  • 5W speaker — Reachy can talk, beep, and play jokes.
  • Accelerometer — Wireless only. Feels tilts and taps.
Real part · camera

The eye is a real camera board

Disassembled white Reachy Mini head shell showing camera cutouts
Head shell · holes where the eye looks out
Cutaway of Reachy Mini showing camera and mic array inside Lite and Wireless
Inside · camera board in the head, speaker in the body
Real part · ears

Four mics on one skinny board

Reachy Mini microphone array board on a cutting mat with ribbon cable
Real photo · mic array + ribbon cable (the nerve)
4
PDM MEMS microphones
16 kHz
How fast they sample sound

They sit in a row on top of the head. That's how Reachy can tell which side you spoke from — same trick as your two ears, with extras.

Based on a Seeed Studio ReSpeaker-style array. Fancy name, simple idea: more ears, better listening.

Real part · brain

These boards ARE the thinking parts

Reachy Mini Lite vs Wireless microphone, control, and power boards
Lite vs Wireless · mic board · control board · power board
  • Mic board — ears, same on both versions
  • Control board — Lite talks to your laptop; Wireless carries the Raspberry Pi CM4
  • Power board — feeds motors. Wireless also has a battery pack
  • Think: sensors in, decisions out, electricity everywhere
Real part · muscles

9 motors = Reachy's muscles

Reachy Mini motor map: antennas, six Stewart motors, body motor
Motor map · 2 antennas · 6 head · 1 body
6
Stewart platform · head wiggles in 6 ways
1
Body spin · look around the room
2
Antenna motors · happy / curious / silly

A Stewart platform is a team of motors pushing a platform from below — like a flight simulator, but for a cute head.

9 DOF

Reachy's wiggle list

Reachy Mini degrees of freedom: Stewart head, body rotation, antennas
Head · body · antennas
Reachy Mini axis limits table and dimension drawing
How far each axis can move
Open the hood

More real Reachy parts

Back ports of Reachy Mini
Back ports · power & USB
Assembly guide showing the head PCB and ribbon cable
Head PCB · connecting the nerves
Reachy Mini head frame diagram
Head frame · the skeleton
Mission control

Safety, then we play

Safety handshake

  • Desktop robot — gentle motors, still: no fingers in joints
  • Don't grab antennas while it's moving
  • Mentors help with cables and assembly
  • Camera & mics only when the class turns them on

Today's quest log

  • Name your Reachy (first name or nickname only)
  • Tour the real parts on the table
  • Launch one plug-and-play behavior
  • Peek at Hugging Face — a library of robot apps
Save game

You now know the cheat codes

World 1

  • Robots sense, think, act
  • Sensors = robot senses (camera, mic, IMU, lidar…)
  • Brain = computer · Learning = practice on examples
  • DOF = one independent move · door 1, neck 3, Reachy 9

World 2

  • Reachy Mini: 12 MP eye, 4 ears, speaker
  • Brain: laptop (Lite) or Pi CM4 (Wireless)
  • 9 DOF · Stewart head + body + antennas
  • Next class: vibe coding — you talk, AI writes the move
Continue?

See you in Class 2

Homework of champions: point at three machines at home and ask — does it sense, think, AND act?

Photo credits

Reachy Mini hardware photos © Pollen Robotics / Hugging Face (Apache-2.0). Curiosity & Perseverance: NASA / JPL-Caltech (public domain). Spot: U.S. Air Force / SrA John Ennis (public domain). Tesla Optimus photo: Steve Jurvetson (Wikimedia Commons). Other robots & sensors: Wikimedia Commons contributors — Pepper, ASIMO, NAO, Atlas, Canadarm2, Tesla, Waymo, da Vinci, KUKA, ABB, FANUC, Raspberry Pi, Deep Blue, camera drone, and more.

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