AI-Avoidance

iNav avoidance using a neural net

Goal: augment iNav with obstacle avoidance. Do it with vision because it's fun and neural net because 80s. Since I'm surrounded by forests, it'll be trained in forests. The idea is to have a solid RTH that'll keep going home while avoiding obstacles.

What we have so far

Using one camera, the NN hardware can recognize obstacles. The accuracy is bad, for example my face isn't an obstacle, so I added images of people in the obstacle folder. Now it's decent. I downgraded from the 75% mobilenet to the 50% to get more free memory to get the MaixPy IDE running.

Hardware

Maix Bit which is small, low power consumption, easy to develop on.

Software

It's all python using keras as NN frontend, the software environment was setup on Windows 10 using Conda.

Training script based on Zipen's mobilenet example: train.py The resulting trained model: avoidance.hl5 Model converted to K210 format using NCC : avoidance.kmodel Script that runs on the Maix: boot.py Firmware: no_lvgl

The neural net

It's a mobilenet 0.50 224x224 which top has been replaced by a dense pyramid 512 -> 128 -> 32 -> 4 Training at 100 epochs is fast, yield loss of 2% and 100% accuracy The training set is about 1000 photos scattered amongst 4 folders

The photos are probably too similar, they're auto harvested from a video recording of me walking in the forest and frankly, with mobilenet base, I don't need many photos so I started taking single photos: same angle with and without obstacle, same obstacle far away=free... you get the idea. The result is already much better.