This robotic platform is based on two stepper motors with the integrated motor controllers which simplifies controller electronics. The direction control is achieved by controlling the speed of each motor.

The robot side consist of Arduino-Uno controler, 2.4GHz radio module, 5.8GHz video transmitter module with camera and 12V battery with DC/DC converter.

The radio module is 2.4GHz E34-2G4D from Ebyte electronics available from Ebay. for $6.00.

https://www.ebay.com/itm/2-4GHz-E34-2G4D20D-Full-Duplex-20dBm-UART-2-4G-Wireless-Transmitter-and-Receiver/191966326509?hash=item2cb215aeed:g:AGAAAOSw2WhdixQw

They are great modules with UART interface that can be easily connected to the Arduino. I used one on the robot side and one in remote controller. They must be to the different channels and to the proper baud rate. Please see the pdf manual for the instructions on how to configure the radio.

The remote controller consist of 2.4GHz radio module, Arduino-Nano, DC-DC controller and 5.8GHz video receiver. 

The motion control was implemented by using simple joystick encoder whose X and Y outputs are read with the Arduino analog inputs. The X and Y values are converted to position commands and transferred via radio to the robot.

The controller box is supplied with the external 12Vdc power supply.