Decoupled suspension

Here are our CFD links and discussions about aerodynamics, suspension, driver safety and tyres. Please stick to F1 on this forum.
User avatar
Zynerji
110
Joined: 27 Jan 2016, 16:14

Decoupled suspension

Post

Not sure if this is the place, but this was eye opening for me!


User avatar
Stu
Moderator
Joined: 02 Nov 2019, 10:05
Location: Norfolk, UK

Re: Decoupled suspension

Post

Zynerji wrote:
11 Feb 2022, 20:36
Not sure if this is the place, but this was eye opening for me!

That is a very interesting video!
I had a linked hydraulic system on my drawing board for ages (way too many years ago!), that was part of very outlandish car design/concept. I was attempting to creat something that would work without electronic control to effectively decouple (although I didn’t know that it called decoupling at the time!) all four suspension modes. I never did fully solve it…
Perspective - Understanding that sometimes the truths we cling to depend greatly on our own point of view.

NL_Fer
NL_Fer
82
Joined: 15 Jun 2014, 09:48

Re: Decoupled suspension

Post

I believe the current rules doesn’t allow for an actual interconnect (FRIC) between front and rear. But the designers have to simulate the same effect, without an interconnect and only the 3 springs/dampers on each axle.

User avatar
Stu
Moderator
Joined: 02 Nov 2019, 10:05
Location: Norfolk, UK

Re: Decoupled suspension

Post

NL_Fer wrote:
13 Feb 2022, 11:14
I believe the current rules doesn’t allow for an actual interconnect (FRIC) between front and rear. But the designers have to simulate the same effect, without an interconnect and only the 3 springs/dampers on each axle.
This is true, no interconnection between each axle.
For this year, any connection across an axle must be by mechanical means only.
Perspective - Understanding that sometimes the truths we cling to depend greatly on our own point of view.

User avatar
henry
324
Joined: 23 Feb 2004, 20:49
Location: England

Re: Decoupled suspension

Post

IIRC, Malcolm Smith, Cambridge Professor, made a model of a fully decoupled suspension, I think the connections were hydraulic. I had a paper describing it, but I’ve lost it.

The inerter is a more famous contribution of his to suspension technology.

Edit: the paper is titled “ Interconnected vehicle suspension”, MC Smith GW Walker , 2005. I can’t find an online copy but it might still be available somewhere.
Fortune favours the prepared; she has no favourites and takes no sides.
Truth is confirmed by inspection and delay; falsehood by haste and uncertainty : Tacitus

Greg Locock
Greg Locock
235
Joined: 30 Jun 2012, 00:48

Re: Decoupled suspension

Post

One of the best lecturers I had. The Kinetic suspension allows for fully hydraulic interconnect and was used in a UWA FSAE car, and various Toyotas. https://en.wikipedia.org/wiki/Kinetic_D ... ion_System

There's a valve block in the interconnects which can be as complex or simple as you like.

User avatar
Stu
Moderator
Joined: 02 Nov 2019, 10:05
Location: Norfolk, UK

Re: Decoupled suspension

Post

henry wrote:
13 Feb 2022, 11:30
IIRC, Malcolm Smith, Cambridge Professor, made a model of a fully decoupled suspension, I think the connections were hydraulic. I had a paper describing it, but I’ve lost it.

The inerter is a more famous contribution of his to suspension technology.

Edit: the paper is titled “ Interconnected vehicle suspension”, MC Smith GW Walker , 2005. I can’t find an online copy but it might still be available somewhere.
Thanks Henry, I’ll try to search for it. 👍

Is this it? ⬇️
http://www-control.eng.cam.ac.uk/Homepa ... l_1014.pdf
Perspective - Understanding that sometimes the truths we cling to depend greatly on our own point of view.

Greg Locock
Greg Locock
235
Joined: 30 Jun 2012, 00:48

Re: Decoupled suspension

Post


User avatar
henry
324
Joined: 23 Feb 2004, 20:49
Location: England

Re: Decoupled suspension

Post

Yes, that’s it. I guess all search engines are not created equal, or maybe search operators. I only found references, not the paper itself.
Fortune favours the prepared; she has no favourites and takes no sides.
Truth is confirmed by inspection and delay; falsehood by haste and uncertainty : Tacitus

User avatar
Tim.Wright
330
Joined: 13 Feb 2009, 06:29

Re: Decoupled suspension

Post

I did some analysis on the characteristics of an interconnected suspension here a few years ago. My version had no warp stiffness.
viewtopic.php?p=574169#p574169
Not the engineer at Force India

User avatar
Stu
Moderator
Joined: 02 Nov 2019, 10:05
Location: Norfolk, UK

Re: Decoupled suspension

Post

Tim.Wright wrote:
14 Feb 2022, 21:17
I did some analysis on the characteristics of an interconnected suspension here a few years ago. My version had no warp stiffness.
viewtopic.php?p=574169#p574169
That is excellent, thank you for sharing it again!
Perspective - Understanding that sometimes the truths we cling to depend greatly on our own point of view.

User avatar
Honda Porsche fan
1
Joined: 16 Sep 2022, 05:44

Re: Decoupled suspension

Post

Does the decoupled suspension have anything to do with the the Benetton Renault Tuned Mass damper of 2005 that was banned ?

If not, could you add a tuned mass damper to a decoupled hydraulic suspension or FRIC with added benefits or will it be redundant or cause negative issues?

The tuned mass damper was tuned to counteract yaw motion.

"How Renault F1 won a World championship by creating the tuned mass damper."...
https://mooregoodink.com/how-renault-f1 ... ss-damper/

johnny comelately
johnny comelately
110
Joined: 10 Apr 2015, 00:55
Location: Australia

Re: Decoupled suspension

Post

Stu wrote:
13 Feb 2022, 10:57
Zynerji wrote:
11 Feb 2022, 20:36
Not sure if this is the place, but this was eye opening for me!

That is a very interesting video!
I had a linked hydraulic system on my drawing board for ages (way too many years ago!), that was part of very outlandish car design/concept. I was attempting to creat something that would work without electronic control to effectively decouple (although I didn’t know that it called decoupling at the time!) all four suspension modes. I never did fully solve it…
Jules Bianchi's uncle designed a system that separated bump and rebound both in springs and damping, he approached Peugeot and others but it didnt break into the mainstream.

User avatar
henry
324
Joined: 23 Feb 2004, 20:49
Location: England

Re: Decoupled suspension

Post

Honda Porsche fan wrote:
21 Oct 2022, 23:17
Does the decoupled suspension have anything to do with the the Benetton Renault Tuned Mass damper of 2005 that was banned ?

If not, could you add a tuned mass damper to a decoupled hydraulic suspension or FRIC with added benefits or will it be redundant or cause negative issues?

The tuned mass damper was tuned to counteract yaw motion.

"How Renault F1 won a World championship by creating the tuned mass damper."...
https://mooregoodink.com/how-renault-f1 ... ss-damper/
The mass damper on the car handled heave and pitch.

The yaw that is referred to is on the wind tunnel model.
Fortune favours the prepared; she has no favourites and takes no sides.
Truth is confirmed by inspection and delay; falsehood by haste and uncertainty : Tacitus

User avatar
Honda Porsche fan
1
Joined: 16 Sep 2022, 05:44

Re: Decoupled suspension

Post

henry wrote:
22 Oct 2022, 01:04
Honda Porsche fan wrote:
21 Oct 2022, 23:17
Does the decoupled suspension have anything to do with the the Benetton Renault Tuned Mass damper of 2005 that was banned ?

If not, could you add a tuned mass damper to a decoupled hydraulic suspension or FRIC with added benefits or will it be redundant or cause negative issues?

The tuned mass damper was tuned to counteract yaw motion.

"How Renault F1 won a World championship by creating the tuned mass damper."...
https://mooregoodink.com/how-renault-f1 ... ss-damper/
The mass damper on the car handled heave and pitch.

The yaw that is referred to is on the wind tunnel model.
Does a fully decoupled hydraulic suspension with FRIC remove the need for a mass damper? Or could a mass damper be added with additional benefits?