Mechaduino is a board that sits on a regular stepper motor and turns it into a servo with a closed loop control of 0.1degree.

[Frank Herrmann] had an interesting idea to turn a geared DC motor into a servo motor assembly, but with a stepper motor-like interface. By stacking some small PCBs behind the motor body, it was po… ...

Makers, developers and Arduino enthusiasts searching for silent stepper drivers with high resolution encoders which are also Arduino compatible.

A new open source robotic arm has this week launched over on Kickstarter called the Dobot, providing an Arduino powered high quality 4-axis parallel-mechanism robot arm.