Drone ESP32

🚁 ESP32 Drone Controller Board

A Wi-Fi/Bluetooth micro-drone where the PCB is the airframe. Flight controller, motor drivers, sensors, and LiPo charging all sit on one 2-layer board.

✨ Highlights

• PCB airframe: four arms with integrated motor mounts and slot-in landing legs, ~103 × 104 mm, so no separate frame is needed.
• ESP32-WROOM-32E with an on-board antenna keep-out, for Wi-Fi / BLE control.
• Four brushed-motor channels: logic-level MOSFETs with flyback diodes, gate resistors, and gate pull-downs on every channel.
• Flight sensors: a 6-axis IMU and a barometric pressure sensor for altitude hold.
• USB-C: programming through a CH340K USB-UART bridge with auto-reset, plus single-cell LiPo charging.
• Manufacturing ready: Gerbers, drill files, BOM, and CPL.

🧩 Block Diagram

flowchart LR
    USB[USB-C] --> UART[CH340K<br/>USB-UART]
    USB --> CHG[TP4056<br/>LiPo Charger]
    CHG --> BAT[(1S LiPo)]
    BAT --> LDO[AP2112K<br/>3.3V LDO]
    LDO --> MCU[ESP32-WROOM-32E]
    UART -- auto-reset --> MCU
    MCU -- SPI --> IMU[LSM6DS3<br/>6-axis IMU]
    MCU -- I2C --> BARO[LPS22HB<br/>Barometer]
    MCU -- PWM x4 --> DRV[4x SI2302<br/>MOSFET drivers]
    BAT --> DRV
    DRV --> M[4x Brushed motors]

🔧 Key Components

Motor PWM pin map (for firmware)

🖼️ Gallery

PCB Layout (F.Cu / B.Cu)	3D View (Bottom)

📐 Schematics (click to expand)

Sheet	Preview
Top level
01 – ESP32 Core & Connectivity
02 – Power Management & LiPo
03 – Motor Drivers & EMI Protection
04 – Autonomous Flight Sensors

📊 Board Stats

🔁 Revision 2

Rev 2 fixes the issues found while assembling the first board:

• USB-C: both D+ pins (A6/B6) and both D− pins (A7/B7) are now tied, so USB works in either cable orientation.
• CH340K:
  • UD+/UD− corrected.
  • TX/RX now crossed to the ESP32.
  • V3 tied to VCC (required at 3.3 V).
• Motors:
  • Drain traces widened to 0.8 mm.
  • M2 moved from IO14 (which outputs PWM at boot) to IO12, which the gate pull-down holds low at boot.
• Power:
  • 10 µF input capacitor at the LDO (C18, bottom side).
  • 100 nF filter on the battery-sense ADC (C19, bottom side).
  • Footprint for an optional 100 µF bulk capacitor on the battery (C17, not fitted).
• Mechanical: arm slots and leg notches widened from 1.33 mm to 1.80 mm, so the 1.6 mm landing legs fit.
• DRC: board-edge clearance check re-enabled. A custom rule exempts only the joint solder pads.

All top-side footprints are unchanged from Rev 1, so the original paste stencil can be reused. Full review: docs/Rev2_Design_Review.md.

📁 Repository Structure

Drone_ESP32/
├── Drone_ESP32.kicad_pro / .kicad_sch / .kicad_pcb   # KiCad project (top level + PCB)
├── Drone_ESP32.kicad_dru        # Custom DRC rules
├── ESP32_Core.kicad_sch         # Sheet 01 – MCU, USB-UART, auto-reset
├── Power_Management.kicad_sch   # Sheet 02 – USB-C, LiPo charger, LDO, power switch
├── Motor_Drivers.kicad_sch      # Sheet 03 – 4x MOSFET motor drivers
├── Sensors_Suite.kicad_sch      # Sheet 04 – IMU + barometer
├── Drone_Custom.3dshapes/       # 3D model for the USB-C connector
├── Gerbers/                     # Gerbers, drill files, JLCPCB zip
├── BOM.csv · CPL.csv            # Bill of materials and placement (JLCPCB format)
├── docs/                        # Design review
├── DATA SHEET/                  # Component datasheets
└── images/                      # Renders & schematic exports

🏭 Manufacturing

Bare PCB:

1. Upload Gerbers/Drone_ESP32_JLCPCB.zip to JLCPCB.
2. Order with these options: 2 layers, FR-4, 1.6 mm, HASL.

Assembly (optional):

1. Enable PCB Assembly and upload BOM.csv and CPL.csv.
2. Review part placement and rotation in the preview before ordering.
3. C18 and C19 are on the bottom side, and C17 is not fitted.