I'm an engineer also and am very interested to learn the intricacies of how the system works. I have not been able to find very much information other than some very broad statements about stiffening the front for braking, and the rear for acceleration. There has got to be more going on than that. For example, does the DDC analize the sensors to determine if it is beneficial to soften the ride when it senses bumps? What parameters does the race calibration kit allow for adjustment? Can you tell it how much to stiffen or soften for certain events? It seems that with the huge variety of conditions encountered on the street that the 2D sensor would be just as beneficial as on the track.
I have been working on understanding this 2D sensor because for me, as a racer, if I dont understand how something works, I cannot get all of it potential out of it. Some racers can just get on a bike, car, boat, airplane and just start going fast. Someone else sets up the race item, and they go.
Now the understanding every one should have is what works for one person will not work for another. I dont care if it a car or motorcycle.. what works for Rossi does not work for Lorenzo. There is somewhat base line however.
So the first baseline on the suspension is usually 30mm sag. That is a magic starting point and maybe if you weight in at 250 lbs, and you cannot find a spring to accomplish 30mm, you might have to live with 45mm. Just dont try to go 10mm sag. You unload the suspension over a rise, bump or whatever, the tire loses contact patch area.
Ok, I know the answer on a question I saw someone post in one of the other 2D sensor what does it do threads.
Why is 20mm important on the setup of the upper bracket. This bracket is on the fork tube. It can move up and down quite a bit. The answer is part of the picture I have attached to this posting as well. You are working with a 5V potentiometer that moves 150mm per say. This is a linear potentiometer. You have a starting point and an ending point.
CALIB > DONE ! 100% needed. Every time you try to CALIB it better hit DONE and not fail. I know now it is reading the potentiometer on the swing arm, and now my front 2D sensor. The voltage at SAG is a variable that is stored as an integer and used to know when the suspension is going up ( uncompressed ) and down ( compressed ) .. i dont care if your voltage is 1.01010 at SAG, this number is stored in the ECU when CALIB is started, and this process finishes with DONE. Anything else is wrong as in FAIL ..
POINT A is at rest 30mm SAG ( if we are using a baseline here ) Guess what the voltage is on the output signal of the 2D sensor is at 20mm ( there about starting point ) on the fork tube? 1.024 pretty much think that the engineer was shooting for 1.0V @ baseline SAG ( 30mm in my case today )
Now, the suspension needs to unload all the way on the front end... Why? We do wheelies on exit of corners since we have the most awesome S1000RR made today and wheelie control when set right will skim that front tire above the ground 6 inches. Well, the 2D sensor is now at .5V with the suspension unloaded. You do not want it at ZERO I can assure you. The engineer did not write the code to read a zero reading under proper setup and working function. That is NOT point B either. It is more like point C as in it travels the least amount but is so important that the ECU knows when lift is occurring beyond the accellometer telling it that wheelie is in action.
Now, the suspension needs to do it job with the front tire on the ground at what point? Bumps, rises, falls, BRAKING ! This is really where DDC shines.
Point B is anywhere from baseline SAG to bottom of fork.
Another point of interest. The 2D sensor is compressed 1 inch from baseline and guess what the voltage is.... 2.015V ( again see attached picture of how the linear voltage works )
We are at 5V @ 150mm stroke. I have never yet been on the brakes hard enough to compress my fork seal to the bottom of the tube stop.
This is all I know I can write about the sensor at this point. My mind is getting wore out for the day.
I cannot tell you anything about the software that controls DDC as I am pretty sure no on this forum can either. Dagor6 is about the only person I seen posting about the ECU workings in fueling, timing, and other aspects that Bren, OEMtune, Alpha.. are all wacking at each other on whos tuning what EFI the best.. No one fighting about tuning the DDC however and how it works that i have seen.
Really, we take a 2D sensor to the front end. Give the ECU information about travel up and down... DDC is applied in someway that some engineer spent countless hours writing code for.
It works and I wanted it, and I have it now.
Oh, I should note that the attached JPEG is my notes in the bottom right corner. I added those so I could remember what my numbers are couple weeks from now when I check them.