Use a 32ch RTRobot servocontroller with USB/UART
A cheaper and more accessible version of Lynxmotion controller board. For this one you have to initialise it before using it (There is no documentation about that, i had to find it myself, so to save your time here is it).
You have to send these first : ASCII : ~RT~OL HEX : 7E 52 54 7E 4F 4C
You will receive this response from the controller :
ASCII : RT HEX : 52 54 17
At the end of every command sen you have to include “\r\n”