RC Crawler
Apparently as a kid I broke up all my RC cars to look inside and learn how they work, I failed. And one point my parents stopped buying me RC cars. I waited a loooong time, but I learned how they worked! And of course I had to make one myself. My first attemp was a KNEX car. I love KNEX! I fell in love with them when they were giving very small kits of it with newsletters when I was very little. When I had a job and had the money to buy them they were not available in my country, so I bought a set from Amazon US, thinking no way it would arrive, and it did! It was a lot of fun to build, I just love gears. But it was not exactly what I had in mind, so it got disassembled.
My second attempt used those generic yellow geared motors with an esp8266 and DRV8833 driver. But I did not want a normal RC car, I wanted it to be driveable in many different surfaces, and wheels that come with the motors did not have much grip. So I moved to wheels from KNEX. Alas, the KNEX wheels did not cut it either, I kind of placed that project on back burner. Some time later I found the perfect wheels from banggood. Ordered immediately. They were 12 cm high, perfect off-road wheels. But of course I could not drive them with those yellow motors, so the search for the motor begun.
I wanted this vehicle to be slow but powerful, I needed geared motors. They were pretty expensive which led me to second hand market and scrap yards. After couple of months I found my motors, 12v 150 RPM metal geared motors from a scrap yard. I needed 4, but I bought 5 and made a hand crank powered emergency lamp from one of them.
Those motors were powerful alright, and consequently poor DRV8833 had no hope of driving them. I ordered a pair of BTS7960B, saw them on a James Bruton video. For power, I used my 3s4p battery pack I made from 18650 cells I salvaged from flea market find laptop batteries. It was starting to take shape! At first I was using Blynk. After another break from the project I found out they removed the app and changed focus. This gave me the push I needed to make the car truly RC.
Next addition was NRF24L01+. Code side of things were easy with Blynk, and NRF24L01+ pushed me to learn more and more of Arduino environment. I had to build a remote controller too. 