Simple partly 3d printed lawm mowing robot with stm32 blue pill and Zephyr RTOS
New version pushed to master, this one has support for ADC monitoring of the battery voltage and current sensor (with ACS712).
I also added new photos with full covers - 3d printed in 5 parts and hot glued together :D
The static back support radius and size got bigger as the robot got stuck constantly on my un-even yard. This new larger one made quite much better, but it still gets stuck. I ordered larger motors. Another option could be to make code somewhat handle the 'getting stuck' by trying to reverse, rotate, and retry or similar. But lets see how it goes with new motors --if-- when they arrive from China.
The mower blades got upgrade from "cutted from plastic food package" to steel bend-wire -- turns out that the food plastic package does not withstand 3000rpm with grass. Go figure.
I am also thinking of updating the drive logic - that currently tries to relay on nice 90deg turns and keeping 'almost perfect' track with wheels - to simpler and similar to what i observed on youtube. A 'grass detector' would be good but i think i could go with keeping x,y location tracking based on wheel rotation.
I also made driver for MPU9250 to zephyr (https://github.com/zephyrproject-rtos/zephyr/pull/24705) but i have not integrated it to the mower. Basically it could be used to eliminate some of the wheel tracking error, but its not that simple i am afraid.