Quote:
Originally Posted by msk340i
What I understood is PAS has "2 rack-and-pinions" and that can produce an adjustable Ackerman angle on tight turns which is actually more beneficial than DAS. DAS can only produce the same angle on tight and wide turns on the other hand.
That tells us that Ferrari are onto the benefits of a steering system with variable toe angles/Ackerman angles. Mercedes' solution leaves it to the driver whole Ferrari's solution leaves it to the double rack-and-pinion.
Side note: every time I read about DAS explained by engineers (Mercedes and other) they always say that DAS's main advantage is on the straight not as most people think that it's for the turns. Because DAS produces a zero toe-in and that decreases resistance on the straights. That made them mention high speed circuits not low speed ones like Monaco.
|
"The W10's power steering arrangement was equipped with a double rack and pinion setu-p, creating a variable Ackermann system that made it possible to make one wheel steer independently of the other, depending on the given steering input."
i guess this part, answers some of your questions about 2-rack and on..
about DAS.. actually the point is, may sound a bit geeky but not like 0 toe, if you set a car for a bit toe-out on front and toe-in on the back thats the ultimate way for free flow on the straights and stability.. Indy cars use it for example.. makes things better for initial part of the corner as well by this..
and if you re not fantasizing with caster especially, having toe-out more exaggerated will help reduce understeer and if your car is grippy on front it ll give pointy front end mechanically if your rear of the car is grippy to handle that.. this concept was already with W10 maybe even backwards.. and almost of the race cars ultimate goal.. cause by this you give less steering effort to take the front wheels off the center.. so with this in mind, DAS helps to concentrate much more corners without compromising straight line alignment for less scrub since you can change them..
for high speed tracks and tracks like Monaco part.. its not about high speed tracks.. its all about straights.. before DAS you had to think about the straights as well.. but by DAS you have more room to play with alignment since you can neutralize your cornering setup on the straights.. i suggest you to watch first few laps of Bottas in pre-season testing, how car acts weird when he was moving the steering wheel on wrong times.. basically we re telling almost the same thing.. what Merc' engineers are telling is this also except with the hidden part.. they re not telling that we dont need to think about straights anymore cause they can now eliminate cornering setup on straights.. race cars adjusted to corners not straights.. the reason why we have DRS.. though there are exceptions like Monza.. cause most the lap is full throttle without not much lateral force teams set their cars to low drag.. and when you think about best teams on speed traps tends to struggle in Parabolica.. cause they re thinking more for the straights with less downforce..
for ackermann part.. and after lets say after putting 5-6 degree of steering angle its totally different affect on the car than basic toe-in or out.. ackermann becomes important on really slow corners that not much aerodynamic factor is in play anymore.. like the slowest corner of the season U turn in Monaco and the chicane.. and Monaco is the track we see most anti-ackermann setup on entire calendar and front toe adjustment of course + camber.. to achieve the optimal slip angle on slow mechanical corners.. the less vertical load a tyre has, the lower the amount of slip angle it can sustain.. and actually thats why i was wondering how high could Merc' fly with DAS in corners since they could change the geometry for the straights.. that was my point.. cause they wouldnt need to think for the straights anymore.. and this is why Merc' engineers came up with this idea.. having more room to play for corners and shred more time in corners without thinking for straights anymore when they want..
for PAS.. this part of the article..
"Having the ability to vary the Ackermann angle depending on the corner's profile can have some interesting aerodynamic implications."
well ackermann angles varies depending on how much steering angle you put already.. and this part states the difference between DAS and PAS.. though name the PAS is a bit blurry for me.. cause power steering is already been in use for many years in F1.. its not that clear like DAS.. and without thinking of the initial toe setting is only telling half of the story of ackermann setup as well on the other hand..
While PAS is not as advanced as DAS, it was this type of system that Mercedes first began running from the start of 2019 and became the precursor to what it has developed for this year.
as i ve said, it doesnt look hard to copy for other teams.. which it doesnt make PAS less better or something.. its good to see Ferrari is working on stuff except just firing people..
and im pretty glad that we can have chance to talk about technical part of F1 here as well..
