MakerBot Print is our newest print-prepration software, which supports native CAD files and STL assemblies,
allows you to interact with all your printers via the Cloud, and many other exciting new features.
I made one sample (you can see the photos) and I was able to move the the head by applying different PWM on servos. The problem is that it's not linear XY movement - for example to make movement on X you also have to apply changes on Y which requires trigonometric calculations. With the new ST ARM processors (like STM32F401) with built in math coprocessor this task is doable but with simple Arduino UNO boards it's not easy task.
Similar movement was used the Shaper tool