This is my first attempt at a remote controlled model, using Bluetooth Low Energy. The heart of it is a tiny Arduino called Feather, from Adafruit. It has built-in BLE capability, and I have added a motor controller shield and a home-made board to connect servos. The wheels are powered by two geared motors and a sealed lead-acid battery. The arm and bucket are powered by servos. The model is fairly basic, as it was the function I was interested in, but note the hydraulics on the arm and bucket.