Minimal flight computer on a 4-layer PCB with an ESP32-S3-WROOM-1.
- Barometer BMP581 for altitude computation
- IMU STM LSM6DS032x for acceloration and rotation data
- Buzzer for easier commissioning and recovery
- 2-channel Pyro ignition for recovery
- CAN Bus for communication with posible expansion PCBs
- µSD-Card for logging
- remove before flight jumper GPIO38 is pulled HIGH when the jumper is removed
- battery voltage measurement
µMETER provides two separated Pyro Channels. To prevent voltage drops from the ignition the battery is decoupled via two 680µF capacitors. The capacitors are charging/discharging when the ARM-Signal is enabled/disabled for about 2.8 sec. To be sure that the capacitors are fully charged, wait at least 3 sec between the first and second ignition. Alternatively, you can measure the voltage across the electrolytic capacitors on GPIO14.
- USB-C for programming, debugging and data transfer; do not use it for powersupply at flight
- UART for programming and debugging
- remove before flight jumper for inputs
- A 4p screw terminal for the pyros
- JST-XH 2p socket for battery
- 3p connector Würth WR-TBL for CAN
The ESP is programmed via the UART or USB-C connection. To enter download mode, press and hold BOOTSEL at startup.
You can find STEP files in 6_Export-Fertigungsdaten.
The board is powered by a 2S LiPo battery with 500mAh each.