Atessa Ets Pro

[bobbejaan]

does anyone have some good detail about the drivetrain and the way atessa works in comparison to other cars

at my school we are now learning about diffs and drivetrain of a car and i want my teacher to explane te Atessa ets pro system

bobbejaan
student @ www.iva-driebergen.nl

[GTES-t]

Here's some detail about the drivetrain:






Anyways, Here's what I've come across about ATESSA-ETS. I've seen it standing for ATTESSA (Advanced Total Traction Engineering System for All) and ETS (Electronic Torque Split). The first one sounds odd, but knowing how the Japanese make abbreviations, it sounds about right. A prime example is Toyota's RAV 4 (Recreational Active Vehicle with 4-wheel drive) That's what they even have written on the JDM Rav 4's wheel cover!

Ok, back to the point, here is Attessa's basic description 'monitors the cars handling via sensors and calculates when to divert torque to the front wheels. For instance, in a drag situation where the rear wheels would spin from takeoff ATTESSA would divert power to the front wheels as well, minimising wasted time while the wheels struggle for grip.'

Now, for ATTESSA E-TS Pro, I've found this:
ATESSA E-TS PRO is Nissans 4WD system which transfers power and braking force where it is needed for best performance. Torque is split between front and rear wheels while braking force is split independently to all four wheels utilising ABS. In ordinary driving conditions torque is delivered purely to the rear wheels, however when the car is pushed the computer engages the front wheels and calculates the amount of power split between front and rear.

I don't know if this helps you or not, keep in mind, this is basic info, getting indepth would involve discussing the G-Sensors, computer, the difference between R32 (only electrically operated, pull fuse and it doesn't work, RWD only) and the R33/34 which have some mechanical linkage (requires pulling the front driveshaft to make it RWD, usually done for dyno tests).

[GTES-t]

Also, I came across this awhile back. It's some great GTR (R32) handling criticism and solutions. It doesn't tell you how the system works directly, but it directly involves the components in the system so it may shed light on how it works for you, plus you may find it of interest.

http://www.autospeed.com/cms/article.html?&A=0060

[bobbejaan]

thanks guys

but i thougt ( and hoped )the skyline system was very different from all the other Traction control and ESP systems but it seems the r34 uses the same kind of system

i was planning to show my teacher something he had never seen before

but thanks again

[RazorGTR]

Originally Posted by bobbejaan

thanks guys

but i thougt ( and hoped )the skyline system was very different from all the other Traction control and ESP systems but it seems the r34 uses the same kind of system

i was planning to show my teacher something he had never seen before

but thanks again

Sounds more like the ESP system uses the same concept as the ATESSA system. In fact no other manufacturer's system is the same. What was explained is the simplified version.

The major differences between the R32 atessa system and the atessa pro of the R34 is the sampling rate, and the R33 and R34 transfer case clutch packs is the R33 and R34 come preloaded while the R32 does not. Also the R32 with only 100 samples per second while the R33 and R34 has over 1000 samples per second.

Not with standing how the system actually works also. Unlike a traction control where power is reduced automaticlly or the throttle amount adjusted, with the Skyline you are using the car's full power at what ever level of throttle. Hence you are able to spin up all 4 wheels.

The Atessa system uses a hydrolic pump to pressurize the wet clutch packs in the transfercase. This pressure is variable from 1kg-m to 50kg-m, not in percentage as many think, though as not confuse myself like others use the percentage thing. In fact it is actually a percentage of the avilable torque the pump will make, and clutch packs will take.

Now it is a stand alone computer but also talks to the main ecu for vairous input signals from three lots of sensors, all of which determin the amount of front wheel torque applied at any given situation. Readings are taking from the 4 ABS sensors, G-force sensor(s), and throttle position sensor. All of which effect the amount of power transfered. The ABS sensors and throttle postion sensor play the greatest part and effect the split difference the greatest while the G-force sensors play a secondary roll unless the car goes into a slide or hard cornering come into play or the atessa computer senses there is still wheel spin or you are under very hard acceleration.

As a quick example I'm able to achive around 20 k-m max with lost of traction. That is the G-force sensor and throttle position sensor working together under WOT conditions while if when I ran the car on a grass gymkanna 40 kg-m wasn't uncommon.