Using the Accelerometer

Update Klipper

• Klipper supports the LIS3DH accelerometer on November 13, 2024. If you need to use the LIS3DH accelerometer, you need to update Klipper
• After connecting to the host computer via network, enter the following code (the update may fail due to network issues)

  cd ~/klipper 
  git pull

Add Configuration

#####################################################################
#                       LIS3DH Accelerometer Configuration (Enable as needed)
#####################################################################
[lis3dh]
cs_pin: SHT36:gpio9
spi_software_sclk_pin: SHT36:gpio10
spi_software_mosi_pin: SHT36:gpio11
spi_software_miso_pin: SHT36:gpio12

[resonance_tester]
accel_chip: lis3dh
probe_points:
    125, 125, 20  # Set the coordinates of the nozzle when performing resonance measurement here

User Guide

Install Dependencies

warning

• No need to execute for FLY host, it already comes with the accelerometer dependency package
• Must execute for non-FLY hosts! It is recommended to operate using SSH tools such as MobaXterm_Personal

• Please execute the commands below in order to install dependencies

• Note that depending on the CPU performance, this may take a long time, up to 10-20 minutes. Please wait patiently for the installation to complete. In some cases, the installation may fail if the motherboard's RAM is too low.

  sudo apt install python3-numpy python3-matplotlib libatlas-base-dev

  ~/klippy-env/bin/pip install matplotlib numpy

Test Accelerometer

• Homing is required before execution
• Enter the command below in the console

ACCELEROMETER_QUERY

• For multiple accelerometers, you can specify one to test with ACCELEROMETER_QUERY CHIP=<ADXL>, where <ADXL> should be replaced with the corresponding accelerometer name
• If errors occur, please check wiring and configuration
• A normal output is shown in the image below
  
• This means you can now proceed with measuring resonance compensation

Calibrate Accelerometer

• Home the printer
• Enter the command below in the console to start automatic calibration for X and Y axes

SHAPER_CALIBRATE

• After calibration is complete, execute the command below to save the data

SAVE_CONFIG

• The calibration process may take some time, please wait patiently
• If you wish to calibrate only one axis, you can use the command below

SHAPER_CALIBRATE AXIS=X

tip

Note! If the printer vibrates violently during testing, please press the emergency stop or send M112 to stop immediately

• Excessive accel_per_hz can cause intense vibration, you can appropriately reduce it

  [resonance_tester]
  accel_per_hz: 50  # Default value is 75