Modubot

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Modubot is a modular robotics platform built around cube-shaped modules, each with a dedicated PCB designed for specific functions. These modules can serve as regional controllers, motor controllers, sensor modules, or other customizable components, allowing for a flexible and adaptable robotic system. The entire project is based on STM32 microcontrollers.

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Goal:

The vision for Modubot is to create a flexible, modular platform that promotes hands-on learning and skill development. By using cube-based modules, each with a unique electronic function, Modubot acts as a test platform for experimenting with:

• Protocols
• Circuits
• PCB architecture
• Firmware

This project is a chance to apply and refine engineering knowledge while exploring creative possibilities in robotics.

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Roadmap:

1. ✅ Design First Ever Module (General Purpose) - Accomplished
2. ✅ Create a Simple 2-Wheel Robot with Remote Operation - Accomplished
3. ✅ Write Firmware for CAN-FD, IMU, UART GPS
4. ✅ Create a 2 Degrees of Freedom Arm
5. 🔲 Design a Brushed/Stepper/BLDC Motor Controller Module (MCM)
6. 🔲 Create a Miniature Buggy Rover
7. 🔲 Design 2nd Version of the General Purpose Module (GPM)
8. 🔲 Design Modular Drone (1x GPM + 4x MCM)

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Current Status:

STAGE 2:

The current phase features a 2-wheeled robot designed as a proof of concept. It tests the General Purpose Module (GPM v1) along with:

• SPI to NRF24L01 (used for remote control)
• Servo control

However, the continuous servos faced tuning issues, preventing the robot from driving straight, highlighting the need to shift towards PID-controlled DC motors with encoders for precise control.

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STAGE 1:

The first wave of designs has been completed. The initial PCB design was kept simple to avoid unnecessary points of failure. It functions as intended, though there are some design oversights:

• It cannot handle high current (only 1-2 amps at 12V)
• Limited resistance to back EMF

These issues will be addressed in version 2, after learning more about system requirements.

The 3D-printed structure has also been refined and is expected to remain unchanged unless major issues arise. For quick connections between modules and subcomponents (e.g., PCB bracket), 3D-printed Lego pins (scaled 1.25x) are being used, and for more permanent fixtures, M6 bolts can be inserted in the same holes. Initially, PETG was used for printing, but due to brittleness, the material has been changed to ABS, which is more ductile.