Input Shaper Accelerometer with USB C Port

The Input Shaper Accelerometer PCB board with a RP2040 chip and ADXL accelerometer sensor was designed to make tuning input shaper on your 3D printer easier. No more building your own harness or plugging individual wires into the Raspberry Pi IO ports and risk shorting something out.

Features

1. Base on popular RP2040 and ADXL345 accelerometer sensor

2. Easily transportable to be used on multiple 3d printers

3. Mounting holes on the PCB is based on the Afterburner and Stealthburner toolheads but adapter plates can be easily made for any printer

4. PCB connects via USB-C port

How to Install
1 – Mount PCB to the toolhead with included screws
2 – Log into Raspberry Pi

**If you have never run Input Shaper before you will need to install a few things into klipper.
Run below commands in klipper 

Install numpy
~/klippy-env/bin/pip install -v numpy

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

3 – enter “cd ~/klipper/”
4 – enter “make menuconfig”
5 – copy menuconfig setting from image below

6 – Enter “Q” to save and exit makeconfig
7 – Enter “make clean”
8 – Enter “make”
9 – Once the process is finished we need to copy the file klipper.uf2 via ftp program (I used FileZilla)

• log into Raspberry Pi through FTP program
• klipper.uf2 file can be found in folder /klipper/out/
• Copy this file to your desktop

10 – Connect Input Shaper PCB to the PC

• Press and hold button found on Input Shaper PCB. Button can be found just under the words “Portable Input Shaper”
• Connect Input Shaper PCB to PC via USB-C cable
• Release the button
• A window will open. If a window doesn’t open you can access this through the Windows File explorer. There should be a drive labeled RPI-RP2.
• Drag and drop klipper.uf2 file into the window. Window should close once you drop the file.
• The Input Shaper PCB will reboot and Klipper should now be installed onto the Input Shaper PCB.
• Wait for a few seconds and you can unplug the Input Shaper PCB from the PC.

11 – Log into the Raspberry Pi and plug Input Shaper PCB into the Raspberry Pi
12 – run
/dev/serial/by-id/*
13 – You should see an id with “usb-Klipper_rp2040” This shows there is communication between the 2 boards and is what you will need to copy ID into the below config later in step 14

14 – Copy the below config into your printer.cfg

[mcu PIS]
# Obtain definition by “ls -l /dev/serial/by-id/” This is from step 13
serial: /dev/serial/by-id/usb-Klipper_rp2040_xxxx

[adxl345]
cs_pin: PIS:gpio13
#spi_bus: spi1a
spi_software_sclk_pin: PIS:gpio10
spi_software_mosi_pin: PIS:gpio11
spi_software_miso_pin: PIS:gpio12
axes_map: x,-z,y

[resonance_tester]
accel_chip: adxl345
probe_points:
100,100,20  #This should be the center of your bed so adjust as needed

More info on Input Shaper and Klipper can be found here