XM and CX seats

[captainhaddock]

Interesting reading Russ. But I've been surprised at how hard especially rear seats are, nowadays. So that doesn't go into the long studies you mentioned, any more I guess. Try a new C3, unbelievably bad. DS 4, ditto. Would people like such hard sofa's at home, I wonder.

[russ92xmsed]

Less attention is generally paid to rear seats. As long as the different spectrum of people can sit in them safely and correctly then it's usually okay. It also depends on the car and its intended use. A c3 is a city car or second car, and therefore might usually have kids in the back. so possibly flatter seats might make it better for childrens booster seats.

But interestingly rear seats are usually more compromised than the front..... Usually it's head room...Jag XF... But coupes also are designed to only fit certain sizes of percentiles. Everything is carefully considered, they know adults usually won't fit in the back so they design accordingly. But something like a Rolls Royce or large exec car will then concentrate on rear comfort. Again it's what the design is intended for.

It's all a logistcal balancing equation Jaap.

We were taught a lot of all of this from professional ergonomics professors. One of our tutors was on the team that designed the Aerial Atom. That started life as a student ergonomics project at Coventry Uni, that went to full prototype stage. Then the tutor involved left the Uni, took the car, set up Ariel and sent the prototype back to the Uni in small cut up bits, so they couldn't use it for anything.

Our ergonomics tutor's husband, is a very highly respected ergonomics expert. He, I believe found out why VW Polo owners were complaining about sore ankles and why physio's were treating so many people with these same issues. Turns out VW set the accelerator pedal to high meaning owners with short legs and small feet...usually female...had to stretch and lift their feet of the floor to press the pedal. Resulting in muscle problems. Once proper ergonomic research was completed, this didn't occur again. It seems basic and common sense, but back then these things were not considered.

Ergonomics have improved industrial design immeasurably....but it can't satisfy everyone!

[silverspider]

I had backache in my BX driving 100 km non stop but i never had a backache in Xm and i drove 1000+ Km in 2 days on mountain roads and a lot of mist on the way to destination. Must mention that spheres were almost flat front/rear. Now with all spheres ok i feel like floating with this car.

[casalingua]

Responding to Russ
I think I said most of that in my post.
Me: seats are an ergonomist's nightmare
Russ: It's a really tricky area of design
Me: People are so variable within and between countries
Russ: As everyone is a different size, shape length of leg etc
Me: You can be sure modern seats are quantitatively checked
Russ. Car companies spend a huge amount of time getting these things right
Me: ...but that still means they don't suit some drivers [poorly expressed]
Russ: but exceptions can't be catered for in a mass market.

I ought to have said that using the available data is difficult and the data isn't that good (consistency and interpretation problems, for example) or that readily available. Here I'm citing Porter and Porter and a few of the reference books I've read in my research. The first problem is which data set and for which market. One of the points Porter S. made was that in trying to design a car seat to suit everyone from a Japanese woman (which one? The one born in 1940 or the taller one born in 1990?) to the fattest, tallest average German you could compromise your design totally. What might work quite well for the little and very big person may put off the majority of the target user group. All a competitor needs to do is to satisfy the core group better to win more customers than the firm that wins some extreme customers but provides a necessarily mediocre solution for the mainsteam. I found when packaging for the extremes of headroom (for the tall person) and outward visibility (a low scuttle for the short person, high seat) that I had an ugly high roof and a ridiculous deep window. Yes it was an ergonomic design but unsaleably ill-proportioned.
The next problem is that the various parameters used in ergonomics are not in any way simply related. There is less than 5% chance that a 95%ile height measurement is accompanied by a 95%ile arm length or leg length. Put this way, there are nearly no people who are the same percentile in even a few major measurements. You can be 25%ile in height, 75% in girth an and have 5%ile hands. If you decide to accomodate a 75%ile height man there is a 90% chance your user will not have 75%ile back length or leg length. Having done Porter's course and then read Porter and Porter in a book by Happian-Smith (Google it) I am surprised Porter thought reference to Dreyfus (the data Russ probably used and which I used )was enough. Certainly in the light of my years in the car industry and subsequent research into Inclusive Design/ergonomics, the main lesson from the Coventry course in ergonomics was that even with the best will and lots of time, ergonomics of vehicles is a chancy business.
The Ariel Atom guy was supposedly a tutor on my course. I think if I printed my view of the quality of his contribution to my education ... ... He turned up once in my recollection.

[Dieselman]

Did anyone notice the "Quick Reply" box?

[russ92xmsed]

Casalingua...I am sorry for repeating your words....clearly on the same page and both Cov Grads. My ergonomics tutor was Mrs Porter. Forget her first name!
Your quite right though, ergonomics is a very in depth subject which seems to create more problems than solve. We did use Dreyfus, but we were also given some worked out mannequins to use which was probably a result of some uni research. They included the extreme %tiles 2.5 and 97.5%tile. I think in the end, you simply have to use common sense with a lot of it. No point in designing a car and you can't see out or reach the dashboard. I suppose in the end, people don't sit in cars in a fixed postion, they do move and stretch. I do remember no one liked doing the ergonomics part of a project. It was usually glossed over...and as you say, if you really stuck to what the ergonomics suggest is right, you end up with a ruined design. You can't win either way.

One thing I did not mention, which you probably have...is hip points. They are very critical to seating design and seating position. I believe they must line up in a certain way with the ankle point to get a good seating position. So long ago now though.. can't remember it all.

Simon Saunders was the chaps name. He wasn't there when I was there. Well never bumped into him anyway. Clearly to busy ripping off the Uni and setting up Ariel!