HP Robots | Otto Walk & Roll

Walk & Roll (also known as “Ninja Otto”) is the upgraded, modular walking version of Otto—now redesigned for the HP Robots Starter Kit + Invent expansion. Instead of wheels, this version gives Otto articulated legs that let it walk, step, and move with character.

This is the modern evolution of the classic DIY “Ninja Otto,” rebuilt to fit perfectly into the new HP Robots modular ecosystem.

🧩 What This Module Does

• Replaces the standard wheel bottom with walking legs

• Uses the Invent expansion servos for smooth leg motion

• Fully compatible with all Top, Middle, and Bottom modules

• Lets Otto perform walking, stepping, and ninja‑style movements

• Great for STEM challenges, robotics lessons, or just giving your robot a new personality

🔧 How It Works

• The legs attach to the Starter bottom frame

• Two Invent servos control the left and right leg motion

• The mechanism converts servo rotation into a walking gait

• Lightweight design keeps movement stable and fun

• No soldering—just print, assemble, and plug into the Invent ports

📦 What You Need

• HP Robots Starter Kit (main body, electronics, battery)

• Invent Expansion (extra servos for leg movement)

• 3D‑printed Walk & Roll parts (included in this model)

Buy all necessary hardware parts in a convenient kit here👈 

🖨 Print Instructions

• Material: PLA or similar

• Temperature: PLA ~ 215 °C | PETG ~ 240 °C

• Layer height: 0.2 mm or less

• Perimeters: minimum 3

• Infill: 15% or more

• No supports, rafts, or brims needed

💡 Tips

• Combine with expressive faces or hats to give your walking Otto more personality

• Use the block‑coding app to program walking patterns or “ninja moves”

• Try different feet shapes for stability or style

• Remix your own leg designs—we love featuring community creations

🌍 Join the Community

❤ Like and share, and join our friendly global community of robot builders, educators, and makers. Join today our Otto Builder community