Desk-sized quadruped for under $120
8 hobby servos, an ESP32, and a 3D-printed frame. The cheapest functional quadruped I could design.
I wanted a walking robot that fits on a desk and costs less than a nice dinner. Here's the build log and the BOM.
Goal
Under $120 total, walkable gait, open firmware. No proprietary parts, no SMD soldering, no CNC. Print and screw.
Bill of materials (highlights)
- 8× SG90 servos (MG90S if you can stretch the budget)
- ESP32 DevKit v1
- PCA9685 16-channel PWM driver
- 2S LiPo 1000mAh + BMS + LDO
- PLA filament for frame + feet
Full BOM with links coming with the Phase 2 project pages.
The gait
Trot gait with 4 phases. 100ms per phase. Hip roll held fixed for the first pass; added hip-roll to stabilize turns in v2.