Reply With QuoteThanks for that RMP. I'm well aware of how it works, and have driven several road cars with it and found it sublime on some and just annoying on others.
Anyway, if you've driven 25+ on sand and say that it's bad then that's good enough for me.
Moderator
I haven't kept count. Around 25 I think. And a driver or instructor, seen more in action.Originally Posted by Captain_Rightfoot
Yes, as above. No, they're not all exactly the same, but they all have the same unfortunate effect in sand to a greater or lesser degree.
Most manufacturers disable ESC in low range. Some vehicles disable it in high as soon as a CDL is locked. Some cannot be disabled. Others re-enable at a certain speed. All (I've tested) re-enable after an engine cycle under most conditions.Is it not possible that for a hire vehicle that would be exactly what you want?
Mitsubishi disables their DSC in low range which I am happy with. If you need it off to get through indian head, then low range it is and at least you won't be doing much more than 40 k
OK, this is a technical explanation of problem with Electronic Stability Control (to give it the correct generic name, DSC is Land Rover's version, same thing but marketing has give it a different moniker).
An ESC-equipped vehicle has a number of sensors which tell a computer things like:
- how fast the vehicle is travelling
- the rate of yaw
- individual wheel speeds
- angle of the steering wheel
- accelerator input
- some cars have a pitch and roll sensor too (FL2 for example)
- gear
and more.
From this the vehicle can work out if it is responding correctly to the driver input. For example, if the steering wheel angle is large yet the yaw rate is not consistent with the angle and the speed, then the system concludes the car must be understeering. If the yaw rate is great and the steering is shallow it's probably understeer. Simplistic examples but the point is the computer knows precisely what the car is doing. And it knows within nanonseconds, almost (but not quite) before the car actually starts to get out of control.
The computer then takes corrective action which is increasing or reducing brake pressure to individual wheels for a sort of skid-steer action to correct the course. It may, and this is also crucial for sand driving, chop the throttle. Once the computer is happy the car is now back on the intended track it gives up and lets the driver have control again.
Now anyone who's driven on sand will spot a problem with this. When on any sand but the hardest beaches the vehicle will wiggle around as it follows ruts, naturally understeer in soft sand, roll more around corners at a given speed than bitumen, shimmy as it goes up a dune...the list goes on and suffice it to say that vehicle dynamics on sand are quite different to those on a hard surface (bitumen or dirt) which is what ESC is designed for.
The problem is that ESC sees these shimmies, rolls and slips and decides the world is coming to an end. Compounding the problem is the fact that sand driving needs more throttle than normal driving. So, ESC does it's job -- it individually brakes each wheel, and starts to chop the throttle. Try driving up a dune like that. Simply, you can't. The faster you go, the more ESC kicks in. If you go too slow you don't have the momentum.
So ESC is not designed for sand and is a hindrance. This is why all sand driving courses, and indeed Land Rover themselves tell you to switch it off. Every single one of the ESC vehicles I've driven behaves the way I've described with ESC enabled on sand.
Could a ESC system be designed for sand? Possibly, but it would be very difficult and I really cannot see any manufacturer bothering with the extremely high development costs.
There is an argument for enabling ESC at higher sand speeds but that won't be effective either. At low speed you'd need it off for reasons as above. Let's say the threshold is 40kmph. Well, over 40 the vehicle can still be sliding and shimmying, and thus ESC will kick in. So make it 50? Or 60? Anyway, even if the beach was quite hard then I'd be cautious about enabling it because ESC is designed to presume the underlying surface is hard like dirt or bitumen, not soft, and thus it can be working against you even at higher speeds, and a hard beach is a lot softer than any bitumen. If you had a hard surface with a thin layer of sand then ESC would be fine, in fact excellent.
There is a lot more technical and dynamics discussion around this but hopefully that explains my point of view.
Note that ESC is a fantastic technology and as Cap RF says it is magically good in the environment for which it is designed, which is conventional roads and I for one support the move to make it mandatory. Problem is it doesn't work in sand, so my view is fix the problem by fixing the driver.
ForumSage
Thanks for that RMP. I'm well aware of how it works, and have driven several road cars with it and found it sublime on some and just annoying on others.
Anyway, if you've driven 25+ on sand and say that it's bad then that's good enough for me.
2005 Defender 110
Moderator
It's the same way on sand, the level of intervention varies but losing momentum on a road is just annoying, it won't stop you making it up a slope. On some higher-performance sports cars there a multiple positions from fully on to entirely off. Most 4WDs just have on and off, and off is usually down to around 10-30% of 'on' so it'll still kick in, but only really late, too late to correct a skid, maybe enough to reduce the impact and enough to stop people drifting ;-) 4WD off modes all work fine for sand. Some vehicles like gen 1 Klugers cannot disable it at all which is a problem.
ESC is also a problem in muddy ruts for the reason reasons.
ForumSage
What is going to happen when it becomes mandatory (Didn't I hear that was happening)? There are going to be a lot of useless 4wds out there
2005 Defender 110
Moderator
Yes it will be mandatory from I think 2011, but for some reason Victoria wants to go ahead of the other states. It will apply only to sales new vehicles, not existing ones as ESC cannot be retrofitted (just not economically viable).
It won't be a problem anyway because we can just disable it when we need to and almost all 4WDs can do that. The legislation says it must be fitted, not enabled, although personally I think you'd be mad to have it and not enable it onroad or dirt road.
This comes back to DM's point about drivers needing to understand their vehicles, he was talking about ABS but the point is also valid for ESC.
Off the top of my head from the wagons only the Patrol, Defender and 76 don't have ESC these days.
For the moment utes and the like won't be forced to have ESC, although I can see that happening, probably 2015 (just a guess). It is another nail in the coffin of the Defender as we know it, and for that matter the 7x Series. The Patrol died some time ago, Nissan just didn't realise.
Super Moderator
1. On places like Fraser Island at low tide there is enough area in the littoral zone to have a 4 to 6 lane expressway. At places like Broome and across the top end the littoral zone can be hundreds of metres wide.
Beaches are crown land and mostly under the control of local government. That is why most beaches in NSW have beach driving prohibited. If you can drive to the beach, so can someone who polices it.
2. That is quite a change from blanket statement in your original post.
You won't find me on: faceplant; Scipe; Infragam; LumpedIn; ShapCnat or Twitting. I'm just not that interesting.
ChatterBox
SubscriberNo its not.
I said:
Public rights of way, e.g. beaches where driving is allowed, can be policed because they are covered under statute.You can license people to drive on roads because roads are governed by statute. They are owned either by state or local government and the statutes that govern access to roads can therefore be policed.
Offroad is entirely different. Ownership is the first major factor and access privileges that ensue. Government agencies (e.g. police) do not have right of access without due cause, for example they have to actually know that someone is in the process of doing something that contravenes their license. They cannot sit and wait like they do on roads.
Put another way. If licensing was to be implemented there would be no effective way to police it without first removing people's right to privileged access to privately owned property. Can you see that happening? I can't.
Alan
Alan
2005 Disco 2 HSE
1983 Series III Stage 1 V8
YarnMaster
Years ago, myself and others took 2 wheel drive VW beetles up Frazer Island. You do not necessarily need 4WD for Frazer, so why penalise those in 4wd's. Also took my VW Beetle up other roads marked 4 wheel drive only. I do think owners of 4WD should not be penalised for afew idiots.
Perhaps hire companies should be made to inform hirers of the dangers of a 4wd before they hire it to them. Once I hired a small 2 ton pantec truck to move a friend into a new flat. I was not familiar with that sort of vechile, so took it easy, and had no problems. Surely I should not have to have special tests and licences before I hire such a vechile.
Some years ago we purchased a Ford XC Falcon station waggon that had stiff springs fitted fortowing a caravan. Its handling was terrible, the rear sliding out on evry corner. No 4WD that I have ever driven has handled as bad as that 2WD. Yet people want to introduce special licences for 4WD. How silly.
One Merc post away from being banned...
The proposal has nothing whatsoever to do with city vs country. Let's remember that the catalyst is foreign tourists tipping over 4WDs. Having said that, I do agree that city drivers in general have less exposure to off-road driving conditions and therefore less ability to learn the skill than a country driver.
To reject such a proposal simply because you feel like being forced to prove your ability at something you know you're already an expert at just makes no sense. What if everybody had that attitude when driving tests were first introduced? Some things like this you just have to suck up and do what's required and get on with your life. I don't see any point in opposing the idea so I plan to get on board and push for it.
I am not totally sold on the idea of club membership being a valid alternative to out and out government regulation through licensing. But I still believe club membership should qualify you for a discount as it shows a greater than average commitment to the skill of off-road driving. In your case, the same discount could be applied as a primary producer.
RoverLord
The proposal has everything to do with city vs country. You assume that a driver has no expertise in offroad driving - i.e. that the driver has no experience except in a normal car. This is not necessarily the case and is likely to be a reverse situation when you are talking about a driver who has grown up on a property. What next? A special licence to drive an ordinary car?
What you do not appreciate, is that quite apart from the city/country aspect, the normal car licence allows drivers to drive a wide variety of vehicles, including light trucks and vans which are arguably even more different from a car than are typical four wheel drives. Introduction of a four wheel drive licence logically requires similar licences for these vehicles. This requirement would greatly limit the employment opportunities of a lot of people, both city and country.
And there is no evidence to suppose that a separate licence would do anything significant for safety, because the problem is largely one of attitude, not knowledge or skills - it would simply be another bit of bureaucracy added to a society that is already suffocating in red tape.
John
John
JDNSW
1986 110 County 3.9 diesel
1970 2a 109 2.25 petrol
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