$46 – $260October 2026 check. Otto DIY no longer makes official DIY kits, and the free 3D-print files plus about $46 of parts (Funduino kit €39.90 converted) build the classic biped. HP Robots Otto Starter Builder Kit is $149.95 at Moravia US and $161.20 at RobotShop US, the Creator Kit (shell parts printed separately) is about $130–$200, and walking builds need the Invent expansion ($109.99 Builder, $69.95 Creator), so roughly $260 for an HP walker. Otto DIY started in May 2016, HP Robots Otto launched in 2024.
AvailableScriptedPalm-sizedOpen source3D-printableArduinoKit
≤ 1 weekShipping: In stock (RobotShop US). RobotShop US had 11 HP Robots Otto Starter Builder Kits in stock in October 2026. Moravia's own US store ships from Brno, Czech Republic. The classic biped can be built from the free files with a 3D printer and common Arduino parts sold in the US. RobotShop ↗
Overview
One of the most popular 3D-printable robots, a four-servo biped with an ultrasonic "face" that walks, dances, makes sounds and avoids obstacles, and can be built from cheap parts in an afternoon. It grew out of BoB the BiPed and the Zowi robot, and its maker later merged with Czech firm MORAVIA to launch HP Robots Otto in 2024. Official Otto DIY kits are no longer produced, so the classic biped is now built from the free files or third-party kits. The HP Otto starter kit is actually a wheeled robot, and walking takes the Invent expansion with its own leg mechanisms.
The cheapest way to build a walking robot, as long as it is treated as a craft project rather than a capable biped.
Specifications
| Category | Bipeds · Walks, but doesn't really balance |
|---|---|
| Released | 2016 |
| Country | Czech Republic |
| Availability | Available |
| Programmability | Open source (hardware + software) |
| Built-in autonomy | Reactive · Responds to its surroundings without a map, such as avoiding obstacles or following a person |
| LLM support | Possible via SDK · No LLM features. The original Otto runs Arduino code on a Nano, while HP Robots Otto adds MicroPython and Wi-Fi/Bluetooth, so an LLM would need a custom bridge. |
| MuJoCo simulation | None found · Nothing found. |
| NVIDIA Isaac simulation | None found · Nothing found. |
| Gazebo simulation | None found · Nothing found. |
| Best for | Ages 8+ (maker rating) |
| Vision sensors | Sonar / ultrasonic |
| Actuators | Hobby servos |
| Audio | Speaker |
| Compute type | Arduino / ESP32 / microcontroller |
| Balance type | Scripted |
| Height | About 12 cm (11 × 7 × 12 cm) |
| Weight | Not published |
| Compute | Arduino Nano (ATmega328P) on the classic Otto DIY; HP Robots Otto uses an ESP32 board |
| Speed | Not published |
| DOF | 4 SG90 micro servos (2 hips, 2 ankles) |
| Sensors | HC-SR04 ultrasonic distance sensor, buzzer; HP Otto adds line-tracking IR sensors and an RGB LED ring |
| Balance | No balance control. Shuffling, tilting gait from pre-set servo oscillation patterns, with wide flat feet keeping it upright. |
| SDK | Arduino IDE with the open OttoDIY libraries and Otto Blockly; HP Robots Otto adds a block editor, MicroPython/Python and C++, plus a Bluetooth control app. Designs are OSHW-certified and the original is CC BY-SA 4.0 |
Ratings & reviews
Ratings and reviews load on the live site.
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