Overview

Week 13 brought the holding period to an end as our custom-fabricated PCBs and surface-mount components officially arrived at the lab. Keeping to a controlled, methodical pace, the team focused entirely on unboxing logistics, physical inventory management, and conducting baseline electrical safety checks on the raw unpopulated boards before kicking off the assembly phase.

What We Did

• Inventory Tracking & Sorting: Unboxed the custom 2-layer PCBs and specific board-level components. We cataloged all microcontrollers, sensors, and passives to ensure our physical inventory completely matched our locked Bill of Materials.
• Bare-Board Visual Inspections: Performed detailed visual inspections of the raw PCBs under magnification to check for manufacturing defects, such as trace fractures, misaligned solder pads, or unexpected silkscreen errors.
• Electrical Continuity Testing: Utilized a multimeter to run baseline continuity and short-circuit tests on the unpopulated boards, verifying that the power and ground planes were properly isolated before introducing any voltage.

Key Decisions

• Phased Assembly Workflow: Decided to adopt a strict, step-by-step soldering strategy rather than populating the entire board at once.
  • Why: Soldering and verifying the power regulation circuit first ensures the board safely delivers the correct voltage. This protects our sensitive microcontrollers and I2C sensors from getting fried if there is an underlying hardware issue.
• Enclosure Modeling Freeze: Formally chose to hold off on finalizing or printing any 3D enclosure prototypes until the physical board is completely soldered. This ensures we map the exact, real-world vertical clearances and component heights before committing to a 3D print.

Challenges

• Manual Inspection Bottlenecks: Checking the tiny footprints of the surface-mount components against the raw PCB pads by hand required extreme patience and precision, slowing down our transition to the soldering iron but saving us from potential manufacturing headaches later.

Next Steps

• Set up the soldering station, apply solder paste, and assemble the initial power management subsystem on the first board.
• Verify the voltage outputs of the power system using a digital multimeter.
• Once the board profile is physically finalized with components, take physical measurements to resume the 3D packaging track.