Klipper

Firmware for 3D printers that combines a general-purpose computer, usually a Raspberry Pi, with the micro-controller on the printer board. The computer does the motion calculations and the controller only drives the motors with precise timing. It includes resonance compensation (input shaping), pressure advance, bed mesh levelling, delta calibration and skew correction. It is controlled through browser front-ends such as Mainsail and Fluidd or through OctoPrint. In labs and workshops it gets more out of existing printers. Installation requires basic Linux skills and editing a configuration file.