1992 F1 Active Supension Benefits?

[Testdrive]

I was just looking at the 1992 season and comparing the McLaren MP4/7 and the Williams FW14B
MP4/7 had about 760HP, while the FW14B had about 750HP.
The MP4/7 didn't have TC early in the season.

Judging from the qualifying laps, it seems that Active Suspension has about 600ms to 700ms per lap while TC seems be about the same. The car seems to of had an advantage of like 1.2 seconds over the MP4/7 early in the season.
I'm assuming Active Suspension increase's down-force in corners mostly. I also heard it maintained it's aero balance through out the entire lap.

If it maintained it's aero balance, then COG would work with the same aero balance? or would they shift the Aero Balance 3% behind the COG like those using conventional suspension?

What are your thoughts?

[Just_a_fan]

Active suspension was intended to keep the floor as close to the ground and in a given stable orientation as possible. No pitching under braking or roll in the corners meant the downforce was consistent and the centre of pressure didn't move around. So more downforce (because they could run the floor at the optimum ride height / angle) and the downforce was consistent meaning a stable car.

I have read that the drivers had to trust the car more as they didn't get the cues that they would traditionally get with roll/pitching etc., so the car felt "wrong" to the drivers.

[jjn9128]

Active suspension was designed to keep the car in a condition which was optimal at all points around a circuit. So in low speed stuff the COP would want to be further forward - more front grip - and in high speed turns the COP more rearward - more controllable with understeer. Also, as fuel burned off through a race the COG would tend to go forwards, in those days the fuel tank was further back on the wheebase than modern long wheelbase cars, so the COP would want to shift accordingly to maintain handling balance.

The Williams system was relatively advanced compared to the McLaren one. Listen to Paddy Lowe's Beyond the Grid episode - McLaren were pre-programming theirs so that for every 1m increment of the circuit the attitude was controlled. The Williams system had more of an automated feedback loop based on speed, steer/brake input...etc so it was not suddenly surprised to be in the wrong part of the track (Ferrari's system lost where it was once and dumped Berger into the outside wall coming out of the pits). Williams also had some over-ride knobs and buttons in the cockpit so e.g. on a straight the rear ride height could be dumped to stall the diffuser and increase Vmax.

[nzjrs]

It was endearing to hear in that podcast the comparison that they spent so long tweaking the mechanically complex active suspension, and in comparison the first naive simple control algorithm, slip vs cylinder cutting, traction control system had a much larger effect on total lap time!

[Just_a_fan]

(Ferrari's system lost where it was once and dumped Berger into the outside wall coming out of the pits).

Estoril in '93?

[jjn9128]

(Ferrari's system lost where it was once and dumped Berger into the outside wall coming out of the pits).

Estoril in '93?

https://www.youtube.com/watch?v=R_jmnBiFwKw

Darn tootin'!

[Just_a_fan]

(Ferrari's system lost where it was once and dumped Berger into the outside wall coming out of the pits).

Estoril in '93?

Darn tootin'!

I remember watching that race over Sunday lunch at my parents' house. Both my Dad and I uttered naughty words and stated that Berger was rubbish and couldn't drive in a straight line to save his life. Little did we know it was a mechanical failure.

[Testdrive]

What's interesting Estoril, seems like a track that would benefit mostly from Active Suspension, lots of high speed corners.

If you look at Mansell's time of 1990 - 1:13.595 ( 700 HP)
and 1:12.443 from MP4/8 Mika from 1993 with ( 700 HP)
1990 was using qualifiers, I bet with 37cm rear tread, while 1993 was using 33cm rear tread but a soft tyre with TC and ABS.

The difference is close to 1.2 seconds.

[Stu]

What's interesting Estoril, seems like a track that would benefit mostly from Active Suspension, lots of high speed corners.

If you look at Mansell's time of 1990 - 1:13.595 ( 700 HP)
and 1:12.443 from MP4/8 Mika from 1993 with ( 700 HP)
1990 was using qualifiers, I bet with 37cm rear tread, while 1993 was using 33cm rear tread but a soft tyre with TC and ABS.

The difference is close to 1.2 seconds.

Back when Senna was still at Lotus, he used the Active car to great effect around bumpy street circuits (Monaco & Detroit, if I remember correctly). Although I think that era of Active operated differently to the later versions.

[Jolle]

What's interesting Estoril, seems like a track that would benefit mostly from Active Suspension, lots of high speed corners.

If you look at Mansell's time of 1990 - 1:13.595 ( 700 HP)
and 1:12.443 from MP4/8 Mika from 1993 with ( 700 HP)
1990 was using qualifiers, I bet with 37cm rear tread, while 1993 was using 33cm rear tread but a soft tyre with TC and ABS.

The difference is close to 1.2 seconds.

Back when Senna was still at Lotus, he used the Active car to great effect around bumpy street circuits (Monaco & Detroit, if I remember correctly). Although I think that era of Active operated differently to the later versions.

I believe Lotus had quite a simple but effective active suspension, or more a automatic ride hight/stiffness system. With an increase of pressure of the pilot tube, the suspension was raised, so the car would maintain it’s ride hight at speed, making it possible to run the car lower at low speed. It stil had normal springs and dampeners. The later Williams system was fully controlled by hydraulic actuators (and possibly being the first F1 car with an hydraulic system?)

[pierrre]

i remember when active suspension was introduced by lotus, their explaination for it was for a more consistent suspension load based on fuel weight. i wonder if they secretly applied it to heave upon increased downforce loads as they did not use a heave spring then...it would have been a huge advantage at that time

[Tommy Cookers]

I believe Lotus ......
.....Williams .... fully controlled by hydraulic actuators ... (first F1 car with an hydraulic system?)

has everyone read the old threads wherein that Dave Williams posted ?
the Dave Williams who designed the Lotus system

[Just_a_fan]

I believe Lotus ......
.....Williams .... fully controlled by hydraulic actuators ... (first F1 car with an hydraulic system?)

has everyone read the old threads wherein that Dave Williams posted ?
the Dave Williams who designed the Lotus system

Username DaveW

A search of the forum brings up plenty of things by him although it appears he hasn't posted on here for a couple of years.

[hollus]

Here some of his gems (the voting system has its uses as a filter):

viewtopic.php?p=673900#p673900

viewtopic.php?p=673643#p673643

viewtopic.php?p=508427#p508427

viewtopic.php?p=502450#p502450

[stresseddave]

I believe Lotus had quite a simple but effective active suspension, or more a automatic ride hight/stiffness system. With an increase of pressure of the pilot tube, the suspension was raised, so the car would maintain it’s ride hight at speed, making it possible to run the car lower at low speed. It stil had normal springs and dampeners. The later Williams system was fully controlled by hydraulic actuators (and possibly being the first F1 car with an hydraulic system?)

It was the other way around - the Williams system was a 'slow' active one - basically a hydraulic ram in series with the normal spring so the suspension could and did move without the ram. Perfect for basic ride height control, which in the aero era, was what was wanted without serious expense. Based off what was originally an AP mechanically controlled system.

The Lotus was 'fast' active - no real mechanical springs to speak of, just hydraulic rams simulating spring and damper. Needed a lot more signal processing and response in the hydraulic system to deal with the main suspension and tyre hop frequencies. Way more powerful though. It had proper modal isolation - separate stiffness and damping values in all 4 modes - combined with self-levelling (to any given attitude) and just about anything else you could think of

My first job out of university was playing with both systems (well the AP mechanical rather than Williams) in a very different field of transportation. We ended up playing with variable damping and a lot of system energy reduction stuff - a lot of the time the suspension wants to move under internal forces the way you want it to move, so you just control the movement via ypass rather than trying to drive the ram all the time.

If you search through the Google Patent database, you'll find both systems.

Williams: https://patentimages.storage.googleapis ... 861066.pdf
Lotus: https://patents.google.com/patent/GB8328373D0