Working on an Integration of Dmitry Butyugin Advanced Klipper Stuff

After more than a day of programming, I successfully ported Dmitry Butyugin's advanced Klipper features to my own Klipper fork. It was somewhat challenging because his developments were based on a very old version of Klipper, and numerous changes have been made to Klipper since then. As a result, I had to rewrite significant portions of his code to ensure compatibility. But enough of the programmer's struggles—so, what's in it for us?

🛠️ Smooth Input Shapers

The Smooth Input Shaper feature uses polynomial smooth functions to effectively cancel vibrations at specific frequencies, offering improved performance compared to traditional input shapers. Key benefits include:

• Enhanced Smoothing: Implements a smoothing approach similar to S-curve acceleration with fixed timing.

• Increased Effectiveness: Provides greater smoothing than discrete input shapers, resulting in less blocking with high accelerations precise motion control.

• Faster Print Speeds: Reduces vibrations during acceleration, allowing for quicker and more stable speed changes.

🧵 Extruder PA Synchronization with Input Shaping

This feature synchronizes filament extrusion (Pressure Advance) with the toolhead's motion, reducing artifacts by compensating for changes in toolhead movement. Key improvements include:

• Aligned Movements: Resolves the misalignment between Klipper's existing pressure advance algorithm and input shaping.

• Stable Extruder Velocity: Ensures more consistent extruder speeds, minimizing erratic behavior during extrusion.

• Improved Wiping Behavior: Achieves more reliable retraction velocity, enhancing overall print quality.

⚙️ High Precision Stepping and New Stepcompress Protocol

The new stepcompress protocol and precision stepping feature enhances stepper motor control by refining the step compression algorithm, which is essential for accurately transmitting stepper commands. Highlights include:

• Higher Precision: Adds a second term in the Taylor expansion and uses fixed-point arithmetic, reducing the error margin to approximately ±1.5%.

• Smoother Acceleration Profiles: Enables more effective input shaping and reduces vibration artifacts, leading to smoother and more reliable motion control.

Current Status and Next Steps

These features are not yet part of the THEOS mainline because they are highly experimental and may cause issues or perform suboptimally in certain scenarios. Additionally, integrating Dmitry's code into my fork might have introduced some bugs, requiring extensive testing to ensure stability. Also there is a lack of documentation, that means that using these features requires diving into the source code to understand their functionality and configuration. There is still a significant amount of work to be done before I can confidently integrate them into THEOS's mainline, but they represent some of the most exciting advancements for Klipper.

🚀 Stay tuned for more updates, and feel free to reach out with any questions or feedback!