SpotMicro (SpotMicroAI) parts list

Fully 3D printed hobby robot dog with twelve hobby servos, a Pi or Jetson brain, and a large community of remixes.

Quadrupedsintermediate by Deok-yeon Kim (design) and the SpotMicroAI community

Total parts cost: $300 to $500 (cheapest listed sellers add up to about $363)

Our estimate, not an official total (the docs give no prices). Assumes MG996R servos at about $9 to $15 each, a Raspberry Pi 4, the listed sensors, a 2S pack, about 1 kg of PLA plus some flexible filament, and hardware. Upgrading to the CLS6336HV servos the designer also supports adds roughly $300 to $500.

Exploded view

Tap any part to see where to buy it. Diagram is schematic, not to scale.

Every part you need

Part	Qty	Spec	Where to buy
TowerPro MG996R metal gear servo, 180 degree leg servos	12	Standard size, 4.8 to 7.2V, stall about 2.5A at 6V per datasheet; 3 per leg Cheap enough to replace when they burn out; the docs admit they are underpowered.	The Pi Hut: GBP 9.00 (unverified) 997 RC Raceway: $14.99 (unverified)
JX Servo CLS6336HV coreless servo leg servos (upgrade option)	12	2S high voltage, about 35 kg.cm at 7.4V per servodatabase; needs the CLS6336HV horn prints The stronger servo the original designer updated the model for; swap in for all 12 if budget allows.	Newegg: $59.86 (unverified) single; ships from China
Raspberry Pi 4 Model B (or NVIDIA Jetson Nano) computer	1	Docs list either board; 2GB Pi is enough for the walking code Runs the gait and sensor code and talks to the servo driver over I2C.	Adafruit: $80.00 single; 2GB, out of stock when checked Adafruit: $120.00 single; 4GB
PCA9685 16-channel 12-bit PWM servo driver (I2C) servo driver	1	One board drives all 12 servos; the board's own power path cannot carry 12 servo stall currents Generates the 12 servo signals so the computer does not have to.	Adafruit: $14.95 single; out of stock when checked
MPU-6050 6-DoF accel and gyro (GY-521 style) IMU	1	I2C Body tilt for balance and posture code.	Adafruit: $12.95 single; STEMMA QT version
HC-SR04 ultrasonic sensor distance sensors	2	5V trigger/echo; the echo pin needs a divider for a 3.3V Pi (Adafruit includes resistors) Front obstacle sensing in the head.	Adafruit: $3.95 single; includes 2 x 10K resistors
16x2 character LCD with I2C backpack display	1	I2C 16x2 module Shows status and battery on the back of the robot.	no verified seller yet
Rocker switch power switch	1	Panel rocker switch sized for the rear cutout Main power on/off.	no verified seller yet
7.4V (2S) battery pack battery	1	Docs list a 7.4V pack; size it to fit the body cavity Powers the servos and, through a regulator, the computer.	no verified seller yet
Step-down regulators for servos and computer voltage regulation	2	The docs mention voltage regulators in the bottom shell but name no model; MG996R tops out at 7.2V, and the Pi needs a steady 5V at 3A Keeps servos within rating and the computer from browning out when servos stall.	no verified seller yet
F625ZZ flanged ball bearing 5x16x5 mm bearings	8	Flanged, shielded Shoulder and hip pivots.	Newegg Business: $10.99 (unverified) 10 pcs
Screw and nut set (M5, M4, M3) fasteners	1	8x M5x15, 40x M4x20, 8x M4x15, 48x M4 nuts, 4x M3x20, 28x M3x10, 16x M3 nuts Holds the printed frame, legs and shoulders together.	no verified seller yet

Quantities follow the official SpotMicro (SpotMicroAI) docs: https://spotmicroai.readthedocs.io/en/latest/gettingStarted/. "Unverified" prices come from search listings or older BOMs that we could not confirm on the seller's product page.

3D printed parts

Needed. PLA for everything except the four paws, which print in flexible filament (TPU). Skeleton: two sidewalls, computer slab, two inner and two outer shoulders. Body: top and bottom covers, head, hindquarters. Legs: 4 forelimbs, 4 midlimbs, 4 midlimb covers, 4 upper limbs, 4 paws, half of the limb parts mirrored. Print the horn style that matches your servo (MG996R or CLS6336HV). Files: https://www.thingiverse.com/thing:3445283

Mistakes builders make

The docs say plainly that MG996R servos lack the torque for smooth walking; expect servo failures and budget spares, or go straight to CLS6336HV.
Do not feed MG996R servos straight from a full 2S pack (8.4V when charged); they are rated to 7.2V. Use a regulator.
Do not power 12 servos through the PCA9685 board's own power pins; run a separate heavy servo supply.
Servo jitter is usually supply sag or a noisy signal; builders report large capacitors on the servo rail help.
MG996R clones vary a lot in quality; buy from a seller that names TowerPro.
The docs' purchase links are still marked TODO, so the parts list gives quantities but no official sellers.
Many forks (SpotMicroESP32, spotMicro ROS) use different servos and boards; stick to one project's list.
The SpotMicroAI GitLab repo did not load publicly when checked (2026-10-25); the docs site and the Thingiverse design are still up.

FAQ

How much does it cost to build the SpotMicro (SpotMicroAI)?

About $300 to $500 in parts at current prices, Our estimate, not an official total (the docs give no prices). Assumes MG996R servos at about $9 to $15 each, a Raspberry Pi 4, the listed sensors, a 2S pack, about 1 kg of PLA plus some flexible filament, and hardware. Upgrading to the CLS6336HV servos the designer also supports adds roughly $300 to $500..

Do I need a 3D printer for the SpotMicro (SpotMicroAI)?

Yes. PLA for everything except the four paws, which print in flexible filament (TPU). Skeleton: two sidewalls, computer slab, two inner and two outer shoulders. Body: top and bottom covers, head, hindquarters. Legs: 4 forelimbs, 4 midlimbs, 4 midlimb covers, 4 upper limbs, 4 paws, half of the limb parts mirrored. Print the horn style that matches your servo (MG996R or CLS6336HV).