Is it for an R/C car or something different? I’ve found out that RTAB-MAP works quite nicely, but whether it would be useful for you depends on many factors.
I want to take basically this: https://www.adafruit.com/product/749 (I got a parallax boebot kit when I was younger, before arduino was a thing) and just have it roam around like a robot pet. Mostly to learn and play around and because I think it would be fun.
Never seen that project before, looks cool, but I don't have the hardware required. I DO have ten ultrasonic rangefinders, some gyroscopes and accelerometers and a raspberry Pi camera, and a complete lack of the math knowledge required to implement kalman filters and smart solutions
