PhillipM wrote: ↑
Sat Feb 22, 2020 6:22 pm
I think you'd have some serious issues with steering feedback given the backlash required to make that work Xwang.
The drawing was just to give an idea of a possible arrangement not to say that the number of teeth, the gear ratio and the helical angle depicted (10°) are the correct ones.
In any case if we consider the toe arm attached at 6.5" from the steering axis, a transversal movement of 2.88mm is needed to change 1° of toe when steering is 0.
Such a movement is given by an helical path 1.65° if a longitudinal movement of 10cm is taken in consideration for the steering wheel.
I hope I have not done any error in my calculation and I do not have specific experience in this field of the engineering to know if such an arrangement would give issues but it seems that the system should be not reversible from the point of view of the longitudinal movement of the steering wheel column because a huge force exerted from the toe arm would give rise to a small longitudinal force of the steering wheel while on the other side, a little pushing force from the pilot side would give a high force on the toe arm.
With the numbers above the ratio between toe arm force and steering wheel one is 0.0288 (and a preloaded spring could be added to keep the steering wheel in the cornering position so that the pilot do not have to push and turn the wheel at the same time).
Of course the servo hydraulic steering system should be made in a way to not interfere badly with the DAS (and I think that modifying the servo steering is the most difficult part in case someone want to adopt this system to their car in a rush).
PS I do not know if this tread is the correct one to discuss how DAS could be implemented (I am not discussing if it is legal or not. If it is not should I move this post and the image in anew discussion but I thought that too much different discussions which cover different aspects of the same innovation could be not easy to follow. Let me know please if I have to move. I do not want to go OT).