This repository contains the source code that has developed during my bachelor's thesis. In this thesis I investigate the possibility of creating a prototype circuit board with multiple simultaneous multizone solid-state lidars and an on-board microcontroller. The circuit board is designed to be mounted on the Crazyflie.
The project was successful and a circuit board was built, that could collect data from all sensors and send it to a ground control station.
The on-board microcontroller is an ESP32-S3, which is a dual-core SoC developed by Espressif. It supports both WiFi and BLE, and can be programmed directly through USB with the help of its USB Serial/JTAG Controller.
The solid-state lidar is the VL53L5CX developed by STMicroelectronics. It's a state-of-the art sensor which can measure distances to multiple zones simultaneously, and thus output a 2D matrix of distances. It's configurable to output a matrix of 4x4 or 8x8, and supports a variety of customizable settings such as ranging frequency, number of targets per zone, etc.
The following table contains the main components for the protoype:
| Component | Amount | Description |
|---|---|---|
| ESP32-S3 | 1 | On-board microcontroller |
| VL53L5CX | 5 | Multizone solid-state lidar sensor |
| TPS62A01 | 1 | DC-DC converter |
| LED | 3 | LEDs can always be useful. For instance, they can indicate the state of the microcontroller. |
| Button | 1 | Used to enter boot mode or as normal GPIO |
| Micro-USB connection | 1 | Used to program the ESP32-S3 |
| DS28E05R | 1 | 1-Wire EEPROM, used by the Crazyflie to identify the deck |
| Resistors, capacitors & inductors | x | Necessary for the rest of the components to work correctly. |
The schematic for the main PCB board can be found here and the schematic for the "satellite" board (the small PCB with the sensor) can be found here.
The firmware written in C and is built with ESP-IDF as of version 4.4. You can build the firmware through the cli, with a custom install of ESP-IDF, or you can use Espressifs VS Code extension. Instructions can be found here to set up your build system.
Ensure that your esp-idf environment is activated, then run the following from the root of this repository:
idf.py set-target esp32-s3
idf.py build
To flash:
idf.py -p (PORT) flash'
To monitor the UART:
idf.py monitor -p (PORT)
The firmware of the Crazyflie had to be extended to support the deck, which was done by a fork of the original firmware. To build and flash the Crazyflie ensure that you have the tools that are required for this, which can be found here.
The firmware of the Crazyflie is in a submodule: crazyflie-firmware-slamdeck and can be updated by:
git submodule init
git submodule update
Then, to build the firmware run:
cd crazyflie-firmware-slamdeck
make menuconfig
Then, to enable the deck driver, select:
- Build and debug options
--->Enabled debug build[*] - Expansion deck configuration
--->Force load specified custom deck driver:bcSLAM
Then build it:
make
Finally, put the Crazyflie in bootloader mode and flash it:
make cload
The GUI is written in Python with PyQt. To run the GUI it is recommended to first create a virtual environment. Once this is done it can be installed by the following:
pip install -r requirements.txt.
gui/main.py
Below are some images of the 3D visualization in the GUI.
