cave-crawler-mcu

cave-crawler microcontroller firmware code (Teensy 3.5)

See also:

• cave-crawler-lib that communicates with this firmware
• cave-crawler for "top-level" project

Purpose

Precise time synchronization of multiple sensors:

• IMU (EM71780)
• encoders
• lidars (RPLidar A3, XV11Lidar)

Communication with embedded CPU.

State

Functional.

Code was carefully written in non-blocking manner:

• IMU (EM1780) is timestamped in interrupt
  • encoders are flagged for ASAP readout to get sync between IMU/encoders
  • IMU is read through asynchronous I2C (non-blocking)
• lidar communication is non-blocking and timestamped on first received packet byte
• embedded CPU (host controller) communication is non blocking

All together this achieves 10s of microseconds order worst case loop time.

Platforms

Firmware code written for Teensy 3.5.

Hardware

Combination of:

• IMU (EM71780)
• lidars (RPLidar A3, XV11Lidar)
• encoders
• embedded CPU running cave-crawler-lib

Using subset of above hardware requires modification of top-level cave-crawler-mcu.ino

Dependencies

• serial-nb-arduino
• xv11lidar-arduino
  • Arduino-PID-Library
• rplidar-a3-arduino
  • Arduino-PID-Library
• EM7180 (async-i2c branch)
  • CrossPlatformI2C

License

If somebody needs to relax the license from GPL to say MPL, let me know. There is no problem with that but I no longer work on this project.