clarifying mounting point

docs/is_tuning_generalities.md

@@ -22,16 +22,20 @@ When tuning Input Shaper, keep the following in mind:
   1. Finally, remember why you're running these tests: to get clean prints. Don't become too obsessive over perfect graphs, as the last bits of optimization will probably have the least impact on the printed parts in terms of ringing and ghosting.
 
 
-### Special note on accelerometer mounting point
-Input Shaping algorithms work by suppressing a single resonant frequency (or a range around a single resonant frequency). When setting the filter, **the primary goal is to target the resonant frequency of the toolhead and belts system** (see the [theory behind it](#theory-behind-it)), as this has the most significant impact on print quality and is the root cause of ringing.
+### Note on accelerometer mounting point
+Input Shaping algorithms are designed to mitigate resonances by targeting a specific resonant frequency or a range around it. When setting the filter, **the primary goal is to target the resonant frequency of the toolhead and belts system** (see the [theory behind it](#theory-behind-it)), as this has the most significant impact on print quality and is the root cause of ringing.
 
-When setting up Input Shaper, it is important to consider the accelerometer mounting point. There are mainly two possibilities, each with its pros and cons:
+Choosing the accelerometer's mounting point is important. There are currently three mounting strategies, each offering distinct advantages:
 
-| Directly at the nozzle tip | Near the toolhead's center of gravity |
-| --- | --- |
-| This method provides a more accurate and comprehensive measurement of everything in your machine. It captures the main resonant frequency along with other vibrations and movements, such as toolhead wobbling and printer frame movements. This approach is excellent for diagnosing your machine's kinematics and troubleshooting problems. However, it also leads to noisier graphs, making it harder for the algorithm to select the correct filter for input shaping. Graphs may appear worse, but this is due to the different "point of view" of the printer's behavior. | I personally recommend mounting the accelerometer in this way, as it provides a clear view of the main resonant frequency you want to target, allowing for accurate input shaper filter settings. This approach results in cleaner graphs with less visible noise from other subsystem vibrations, making interpretation easier for both automatic algorithms and users. However, this method provides less detail in the graphs and may be slightly less effective for troubleshooting printer problems. |
+| Mounting Point | Advantages | Considerations |
+| --- | --- | --- |
+| **Directly at the nozzle tip** | Provides a comprehensive view of all machine vibrations, including the main resonance, but also toolhead wobbling and global frame movements. Ideal for diagnosing kinematic issues and troubleshooting. | Results in noisier data, which may complicate the final Input Shaping filter selection on machines that are not perfect and/or not fully rigid. |
+| **Near the toolhead's center of gravity** | Provides a view of mostly only the primary resonant frequencies of the toolhead and belts, allowing precise filter selection for Input Shaping. The data is often cleaner, with only severe mechanical issues or very problematic toolhead wobble visible on the graphs. | May provide less detail on secondary vibrations (which have a fairly minor effect on ringing) and may be less effective in diagnosing unrelated mechanical problems. |
+| **Integrated accelerometer on a CANBus Board** | Simple and effective, requires no additional installation and always available. Can help for diagnosing issues like those caused by bowden tubes, umbillical coords and cable chains. If toolhead is very rigid, measurements are close enough to those of the center of gravity. | Not accurate for a detailed analysis or diagnosing mechanical issues due to distance from the nozzle tip and potential noise from attached components. |
 
-A suggested workflow is to first use the nozzle mount to diagnose mechanical issues, such as loose screws or a bad X carriage. Once the mechanics are in good condition, switch to a mounting point closer to the toolhead's center of gravity for setting the input shaper filter settings by using cleaner graphs that highlights the most impactful frequency.
+While you should usually try to focus on the toolhead/belts mechanical subsystem for resonance mitigation (since it has the most impact on ringing and print quality), you don't want to overlook the importance of nozzle tip measurements for other sources of vibration. Indeed, if resonance analysis results vary a lot between mounting points, reinforcing the toolhead's rigidity to minimize wobbling and vibrations is recommended. Here is a strategy that attempts to methodically address mechanical issues and then allow for the day-to-day selection of input shaping filters as needed: 
+  1. **Diagnosis phase**: Begin with the nozzle tip mount to identify and troubleshoot mechanical issues to ensure the printer components are healthy and the assembly is well done and optimized.
+  1. **Filter selection phase**: If the graphs are mostly clean, you can transition to a mounting point near the toolhead's center of gravity for cleaner data on the main resonance, facilitating accurate Input Shaping filter settings. You can also consider the CANBus integrated accelerometer for its simplicity, especially if the toolhead is particularly rigid and minimally affected by wobble.
 
 
 ## Theory behind it