From 0d3d4b609367ad4b3fc4e7b4f7aa64ec651e649d Mon Sep 17 00:00:00 2001 From: Dmitry Butyugin Date: Sun, 27 Oct 2024 15:17:27 +0100 Subject: [PATCH] docs: Added documentation for sweeping_vibrations resonance test method Signed-off-by: Dmitry Butyugin --- docs/Config_Reference.md | 19 +++++++++++++++++++ docs/Measuring_Resonances.md | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+) diff --git a/docs/Config_Reference.md b/docs/Config_Reference.md index 94379a75430c..24fb40a9ede1 100644 --- a/docs/Config_Reference.md +++ b/docs/Config_Reference.md @@ -1744,11 +1744,23 @@ section of the measuring resonances guide for more information on # and on the toolhead (for X axis). These parameters have the same # format as 'accel_chip' parameter. Only 'accel_chip' or these two # parameters must be provided. +#method: vibrations +# A test method to use for resonance testing. Valid choices are +# vibrations, sweeping_vibrations. The vibrations method tests +# different vibration frequencies at the designated test point. +# The sweeping_vibrations method tests different vibration frequencies +# while also moving the toolhead slowly around the test point, and +# thus may help, for example, if stiction of the toolhead (a force that +# must be be overcome to start toolhead motion) is too high. +# The default is vibrations, which is generally a recommended choice. #max_smoothing: # Maximum input shaper smoothing to allow for each axis during shaper # auto-calibration (with 'SHAPER_CALIBRATE' command). By default no # maximum smoothing is specified. Refer to Measuring_Resonances guide # for more details on using this feature. +#move_speed: 50 +# The speed (in mm/s) to move the toolhead to and between test points +# during the calibration. The default is 50. #min_freq: 5 # Minimum frequency to test for resonances. The default is 5 Hz. #max_freq: 133.33 @@ -1767,6 +1779,13 @@ section of the measuring resonances guide for more information on # hz_per_sec. Small values make the test slow, and the large values # will decrease the precision of the test. The default value is 1.0 # (Hz/sec == sec^-2). +#motion_accel: 400 +# An acceleration of slow moves. Available only for sweeping_vibrations +# test method. The default is 400 mm/sec^2. +#motion_period: 1.2 +# A period of slow moves. Must not be set to a too small value in order +# to not poison the measurements. Available only for sweeping_vibrations +# test method. The default is 1.2 sec which is a good all-round choice. ``` ## Config file helpers diff --git a/docs/Measuring_Resonances.md b/docs/Measuring_Resonances.md index d5f7f54cc537..c61f395ec676 100644 --- a/docs/Measuring_Resonances.md +++ b/docs/Measuring_Resonances.md @@ -683,6 +683,38 @@ If you are doing a shaper re-calibration and the reported smoothing for the suggested shaper configuration is almost the same as what you got during the previous calibration, this step can be skipped. +### Unreliable measurements of resonance frequencies + +Sometimes the resonance measurements can produce bogus results, leading to +the incorrect suggestions for the input shapers. This can be caused by a +variety of reasons, including running fans on the toolhead, incorrect +position or non-rigid mounting of the accelerometer, or mechanical problems +such as loose belts or binding or bumpy axis. Keep in mind that all fans +should be disabled for resonance testing, especially the noisy ones, and +that the accelerometer should be rigidly mounted on the corresponding +moving part (e.g. on the bed itself for the bed slinger, or on the extruder +of the printer itself and not the carriage, and some people get better +results by mounting the accelerometer on the nozzle itself). As for +mechanical problems, the user should inspect if there is any fault that +can be fixed with a moving axis (e.g. linear guide rails cleaned up and +lubricated and V-slot wheels tension adjusted correctly). However, if +the axis has too high stiction (a force that must be be overcome to start +toolhead motion over that axis) and thus binds, or if the user gets +recommended shapers that do not eliminate the echo well on the prints +and troubleshooting did not help, the user may try to use a different +resonance test method that can be activated by adding +``` +[resonance_tester] +method: sweeping_vibrations +``` +option to the Klipper config, restarting Klipper, and reruning the resonance +test again. Note that this test moves the toolhead slowly around the test +point, thus requiring some clearance around the test point over the tested +axis. Since this method may produce higher amplitude vibrations compared to +the default method, it is avised to monitor the printer closely during the +test, and if the vibrations get too strong, the user may need to reduce +`accel_per_hz` value in `[resonance_tester]` section from its default value. + ### Testing custom axes `TEST_RESONANCES` command supports custom axes. While this is not really