RobotDog Controller

ESP32-Robot-Dog-Controller-PCB

Double-layer PCB controller for a robotic dog using ESP32, with four servo outputs, sensor interface, and power management.

Overview

This project presents the design of a custom double-layer PCB controller for a robotic dog based on the ESP32.

The board was designed to organize the electronic connections of the robotic dog into a single PCB, including four servo motor outputs, a sensor interface, and a dedicated power input.

The project started with an initial design sketch to determine the placement of the main components. The design was then implemented and routed using KiCad PCB Editor.

Project Objectives

The main objectives of this project were to:

• Design a custom PCB for a robotic dog.
• Use an ESP32 as the main controller.
• Provide four dedicated servo motor ports.
• Add a sensor interface.
• Add a 5V power input.
• Organize the power and signal connections.
• Design the PCB using two copper layers.
• Clearly label the ports and components.
• Validate the PCB layout using KiCad Design Rules Checker.

Initial Design

The first stage was creating a simple concept sketch to define the location of:

• ESP32 controller
• Servo motor connectors
• Sensor connector
• Battery/power input
• Filtering capacitor
• Mounting holes

This stage helped organize the PCB before implementing it digitally.

Initial Design Sketch

PCB Implementation

After completing the initial concept, the PCB was implemented using KiCad.

The final design uses a double-layer PCB:

• F.Cu — Top Copper Layer
• B.Cu — Bottom Copper Layer

The two layers were used to organize the signal, power, and ground routing while keeping the board compact.

PCB Layout

Main Controller

The board is designed around an ESP32 development board.

The ESP32 provides the GPIO signals required for controlling the servo motors and communicating with the external sensor.

Servo Motor Interfaces

The PCB contains four dedicated 3-pin servo connectors.

Each connector provides:

• Signal
• 5V
• GND

Servo GPIO Assignment

This arrangement allows the robotic dog's servo motors to connect directly to the PCB.

Sensor Interface

A separate sensor connector was included for future expansion.

The interface provides:

This interface can be used with compatible I2C sensors.

Power Section

The PCB includes a dedicated power section for the controller and servo connections.

Main power features include:

• 5V power input
• Common GND
• Servo power distribution
• Filtering capacitor
• Organized power routing

A large capacitor is included to help stabilize the power supply when the servo motors operate.

Pinout Summary

Main Components

• ESP32 development board
• 4 × 3-pin servo connectors
• Sensor connector
• 5V power input
• Filtering capacitor
• 4 mounting holes
• Double-layer PCB

Design Validation

The PCB layout was checked using KiCad Design Rules Checker (DRC).

Final validation results:

• DRC Errors: 0
• Unconnected Items: 0

The validation process was used to identify and correct issues such as track crossings, shorts between power nets, and incomplete connections during the development process.

A final fabrication review of footprints, dimensions, and manufacturer-specific design rules should still be performed before physical PCB manufacturing.

Application

The PCB is intended to be used as the main electronic connection board inside a quadruped robotic dog.

Instead of using multiple independent wires between the ESP32, servo motors, sensor, and power supply, the PCB provides a centralized interface.

This improves:

• Wiring organization
• Reliability
• Maintainability
• Hardware integration
• Expandability
• Overall electronic system organization

Design Workflow

Project Requirements
        ↓
Initial Design Sketch
        ↓
Component Selection
        ↓
GPIO Assignment
        ↓
PCB Component Placement
        ↓
Signal & Power Routing
        ↓
Double-Layer PCB Design
        ↓
DRC Validation
        ↓
Final PCB Layout

Repository Structure

ESP32-Robot-Dog-Controller-PCB/
│
├── README.md
├── RobotDog_Controller.kicad_pcb
├── RobotDog_Controller_BOM.csv
├── RobotDog_Controller_Pinout.csv
├── fp-lib-table
│
├── RobotDog.pretty/
│   └── Custom Footprints
│
└── images/
    ├── initial-design-sketch.png
    ├── pcb-layout.png
    └── pcb-3d-view.png

Tools Used

• KiCad — PCB design and routing
• ESP32 — Main microcontroller
• KiCad DRC — PCB design validation

Future Improvements

Future versions of the board could include:

• Integrated voltage regulation
• Additional sensor interfaces
• Dedicated servo power protection
• Additional filtering capacitors
• Battery monitoring
• Improved 3D component models
• Smaller PCB dimensions
• Manufacturing-ready Gerber files

References

• KiCad PCB Editor Documentation
• Espressif ESP32 Hardware Design Guidelines

Project Categories

ESP32 PCB Design KiCad Robotics Embedded Systems Robot Dog Servo Motors