OpenSCB is a hardware and software solution for controlling servos over USB. The hardware is designed to interface with classic RC servos, AX-12/AX-18 servos, OpenServo, and more using a powerful 32-bit microcontroller with a USB port for programming and control with a PC. The schematic and layout will be available and can be customized. A graphical interface is also provided for your computer to configure, calibrate, and control the board.
ServoMaster provides hardware independent abstractions to servos and servo controllers. It has implementations for several servo controller families, including Phidget, Pololu, Parallax, and SSC. It has support for servo and controller metadata, introspection, and capabilities discovery.