Klipper

Klipper is an open-source firmware package for controlling 3D printers. It uses a host-based architecture in which a general-purpose computer, typically a Raspberry Pi, runs the Klipper host software and communicates with a small firmware installed on the printer’s microcontroller. The host handles G-code interpretation, motion planning, and higher-level computations, while the microcontroller executes precise stepper motor commands and reads sensors.

The printer is described and configured through a single text file, usually called printer.cfg. This file specifies the hardware layout, including stepper motors, endstops, temperature sensors, heaters, fans, probes, and bed leveling settings. Klipper supports a variety of microcontroller boards (such as STM32 and AVR-based controllers) and can drive multiple MCUs or extruders, communicating with the microcontroller(s) over a USB serial connection.

Key features and benefits include high-precision step timing and efficient motion planning, which enable advanced capabilities such as Input Shaper and Pressure Advance. These features can improve print quality by reducing resonance, ringing, and oozing. Klipper also provides robust temperature control, PID tuning, mesh bed leveling, bed probing, and extensive macro support to automate common printing workflows.

History and licensing: Klipper was developed by Kevin O’Connor and a community of contributors and is released as open-source software under a GPL-compatible license. It has gained popularity in the DIY 3D printing community as an alternative to traditional firmware, offering a flexible configuration model and modern motion features.