Mad Bot

Mad_Bot

Exploratory project in Embedded Robotics and Swarm Algorithms

Warning: This is an ongoing project, and the repository is under construction!

Features

• Small PCB-based frame, minimum 3D printed parts
• ESP32-S3 MCU with vector instructions, acceleration for neural network computing and signal processing workloads
• Wi-Fi, Bluetooth 5 and BLE connectivity
• Omnidirectional movement
• Quadrature encoders for precise movement
• 8 MB PSRAM for image processing
• 2 Megapixel camera and ToF sensors for running embedded robotics algorithms
• Powered via USB-C or 3000mAh LiPo battery with inner protection and external charging circuit
• Load sharing circuit for operating the robot while charging
• Buck-Boost converter for powering the MCU and peripherals
• 6V regulator for powering the middle power range motors
• ESPNOW, ESP-WIFI-MESH or ESP-BLE-MESH for communication between several robots
• Integrated MEMS microphone for sound recognition
• micro-ROS support

Note: Software support for some features is still in progress.

Fusion360 design

URDF model

Robot	Wheel

Operation demo

Forward movement	Backward movement	Rotation

Charging mode

Board layout

Future work

• Add a BOM
• Design a carrier extension in Fusion360
• Test battery charging circuit
• Test load sharing circuit
• Test basic functionality with motors and ESP32-S3
• Test Wi-Fi
• Motors library (in progress)
• Encoders testing
• Device firmware (in progress)
• Sensors testing (in progress):
  • Camera
  • ToF
  • IMU
  • MEMS microphone (requires PCB bug fix)
• Remote controller based on ESP32
• PSRAM memory testing
• ROS2 integration via micro-ROS (in progress)
• Web page with control interface and telemetry
• URDF model
• Joystick control via ROS2
• Digital twin for simulation in Gazebo and Mujoco
• ESPNOW and Mesh experiments
• Multi-agent algorithms
• Computer vision algorithms
• Mini SLAM experiments

Fix list for new hardware revisions

• MEMS microphone footprint flipped
• Non-fixed Buck-Boost mentioned in the schematics instead of 3.3V fixed
• 6V regulator doesn't disconnect the load if disabled because of topology - extra switch needed
• Battery connector is hard to remove - source power switch needed
• Better (aligned) placement for camera & ToF sensors

Software Troubleshooting

micro-ROS build issues

If you encounter issue like this building micro-ROS for the ESP32-S3 platform, edit libmicroros.mk file at line 110 to include esp32s3 as follows:

ifeq ($(IDF_TARGET),$(filter $(IDF_TARGET),esp32s2 esp32c3 esp32c6 esp32s3))

Acknowledgements

This project takes inspiration from the following open-source projects:

• https://github.com/YePeOn7/ros2_omni_robot_sim (omnidirectional drive kinematics)
• https://github.com/twistx77/V53L7CX-Library.git (ToF sensor library)
• https://github.com/natanaeljr/esp32-mpu-driver (IMU driver)
• Jonas Scharpf code pf the PCA9685 driver (motor PWM driver)