1. Hardware design

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2. Software design
3. Production
4. BOM and files

Goals

1. Making the machine wireless/battery powered
   • Add a safety circuit and battery monitoring
2. Improving expandability
3. Making the machine compact
4. Improve robustness
   • Resistant to external impacts

Electronics design

• A 12 V 6000 mAh Li-ion battery directly powers the A4988 motor drivers
• Battery voltage is monitored by the Pico’s ADC via voltage divider
• A LM2596 buck converter module converts 12 V to 5 V for the Pico
• UART, I2C, SPI, and extra GPIOs are available for easy expansion such as additional micro controller (e.g., ESP32-S3), an OLED display, sensors, limit switches, a fan, or a servo
• In this setup, the Pico works as the “spine”, and a wirelessly connected PC or additional micro controller works as the “brain”

Schematics

PCB

• Double-sided (LM2596 mounted at the bottom)

Pinout

Mechanical design

1. Modeling strategy (F3D)
   • Use external/internal components
   • Ref: Fusion 360 Components and Assemblies Explained
2. Component layout
   • The 6000 mAh battery at the center bottom between the motors
   • The minimum dimensions defined by the four motors and the battery
3. Frame: Topology optimization (Grasshopper tOpos)
   • Boundary: box excluding space for components
   • Loads: battery, PCB etc.
   • Support: Mounting points for the motors
   • Ref: Topology Optimization 101
   • IsoMesh > Quad Remesh > SubD from Mesh > Export as STEP > Import into F3D

   

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Industrial design

• Simplify the TO results
• Slightly rounded base surface for appearance quality