Torque request setting.

[Lotussuper7]

Can anyone shed some light on the torque request setting.

Is this only used for automatic transmissions that need torque reduction to shift gear, or can it be used to normalize torque on a turbocharged engine ( Ie. make torque output more in line with APS value?)

If so, can it be set up without having the exact torque curve from a dyno?

Currently I have set the E-Throttle map to be quite exponential (negitive) to try and compensate (eg. 50% APS = 35 TPS etc). However, I was wondering if the torque request would be a better way.

Haven't seen anyone else talk about it on the forum, so I just thought id throw it out there.

 

Any advice would be appreciated.

[Adamw]

This is really only designed for OEM automatic transmission integration.  In these the transmission or trans controller asks for a specific amount of torque redution for a gear shift such as:  "Please reduce torque by 64Nm" or whatever.  

To make a turbo engine power more linear with TP you would probably be best to just use TP on the axis of your boost control tables.

[Lotussuper7]

Thanks for the reply. The reason I ask is because the car has a lot of power vs traction and can be a bit unruly. ( Lotus 7 replica) with a turbo 4age under the hood.

I was contemplating using an offset to the E-throttle target using the Map reading to reduce Tps opening as boost builds. Do you think this is a viable solution? and if so, how would I go about it. I cant seem to come up with a solution to offset the throttle target position. 

My idea was to have a separate table with APS and Map that fed into the main E-Throttle target table and offset (replace) the original APS position. I dont want to give up the rpm axis on the main E-throttle table as I find it is useful.

 

Thanks again for you ongoing help.

 

kind regards.

[Adamw]

Yes you could use a GP PWM table to do the APS Vs MAP table then use the output from that table as the axis on your E-throttle target.  Just be careful to consider all possibilities and make sure you validate all conditions so that for instance if some scenario like the boost is too low due to a pipe falling off or something that it doesnt just force the throttle wide open because boost is low. 

Some motorcycles do things like limit throttle position based on gear or speed, so consider strategies like that also.  

A better option would probably be to get wheel speed sensors on it and set up slip based traction control so that the maximum torque the tyres can handle is always available.   

[Vaughan]

I've just been playing with taming my MR2  (3.5l v6) a little due to the large amounts of rain we've been having and what has worked so far is both putting a bigger curve in the aps to tps table and setting up traction control to limit slip.

[Lotussuper7]

Thanks for the reply's. Eventually I will set up traction control, however, I currently only have the front undriven wheel speed. (trying to find the best way to get a drive shaft sensor installed, space is tight).

So if I want to try the Map vs Aps table I would create a GP pwm table, and have the output as a virtual aux, then reference the virtual Aux on the y axis of the E- throttle table?

Thanks again.

 

Tim

[Adamw]

Yeah, but use a CAN aux - a virtual aux can only be on/off.  Then put the CAN AUX duty on the throttle target axis.

Rough example below, ignore the numbers I have in the tables, they are just rubbish I wacked in to explain how it would work.  So lets say you had a MAP of 120 and an APS of 90%, the GP PWM table would generate a duty cycle output of 60.0%.  So your throttle target would be working in the 60% DC row, if you were doing say 3500RPM, the final throttle target would be 54.3%TP.

 

[Lotussuper7]

Thanks. That is exactly what I was after! Going to give this a go. 

I'm going to set it up so it makes no change at 0 Mgp and below, then removes Aps input say 1.5 - 2% per psi of manifold pressure above atmosphere. (As a starting point)

 

This should make it safe, if a boost pipe does come off, no positive pressure will make it into the manifold and so no adjustment to the e throttle  taget will occur. (All adjustments will be negitive regardless)

Should be an interesting experiment.

 

Thanks!

[mapper]

Great idea for what the firmware is now. However I hope a proper torque control strategy which controls TPS and pre throttle pressure. Incoperating ignition amd lambda efficiency (actual vs optimal ign angle), charge temperature etc. 

So the e-throttle table is just a Torque request value. Boost, TPS angle etc. is then adjusted to get the desired torque. 

[Lotussuper7]

That is kinda what I thought the torque request setting was, but I understand its currently just for gear change torque reduction.

Generally it would just be good to have some more flexibility surrounding the e-throttle tables, like offset table/tables based on temps/pressures etc. But a proper torque request strategy im sure would be a very popular feature for people with turbo cars especially.

 

Haven't had chance to test out the idea I suggested on the road yet, as I'm still working on getting the fueling dialed in, have it is set up on it's own e throttle table, and in theory works perfect. It is only a theory though. 

If anyone else gives it a go, post up your thought/ observations here.

[Oprah_152]

On 5/31/2021 at 3:08 PM, Adamw said:

This is really only designed for OEM automatic transmission integration.  In these the transmission or trans controller asks for a specific amount of torque redution for a gear shift such as:  "Please reduce torque by 64Nm" or whatever.  

To make a turbo engine power more linear with TP you would probably be best to just use TP on the axis of your boost control tables.

Sorry to revive an old thread, Will we ever be able to use "Torque Request" parameter as a table axis in the future? I know I have the ability to use the GP Outputs to recreate this table, it just feels silly to have the same table defined twice

I do personally would like to use torque modelling for E-Throttle control. 

[Adamw]

In G4X Im pretty sure you can use absolutely any runtime you like on a table axis.  At least torque request can be used anyhow.  

[Oprah_152]

On 12/28/2022 at 9:25 PM, Adamw said:

In G4X Im pretty sure you can use absolutely any runtime you like on a table axis.  At least torque request can be used anyhow.  

I always get this Error on any of the Torque management parameters

[Adamw]

Ah, I dont think that is intended, I ask the firmware team to take a look when they are back from holiday.  

[Oprah_152]

On 1/3/2023 at 4:55 AM, Adamw said:

Ah, I dont think that is intended, I ask the firmware team to take a look when they are back from holiday.  

Thanks so much! It's very much winter here so no rush haha. 

[Vaughan]

On 1/3/2023 at 10:07 AM, Oprah_152 said:

I always get this Error on any of the Torque management parameters

Have fixed that, will be in the next release