Kia Details Clutch-By-Wire Manual Gearbox For Mild Hybrids
Kia has revealed all the juicy details about its innovative new clutch-by-wire manual transmission to be used by a range of mild-hybrid models, starting with the recently announced 2021 Rio EcoDynamics+.
The South Korean automaker's new manual gearbox doesn't use a mechanical linkage, with the clutch operated purely electronically and integrated with a 48V powertrain.
(https://www.carscoops.com/wp-content/uploads/2020/06/Kia-Gearbox-1.jpg)
This means the intelligent Manual Transmission (iMT) works with the mild-hybrid starter-generator to switch off the engine earlier than Kia's Idle Stop& Go start-stop system. As a result, it improves overall fuel efficiency and reduce CO2 emissions by around 3 per cent in real-world driving conditions.
The gearbox is particularly helpful when coasting. As the driver leaves the car in-gear while coasting, the iMT sends an electronic signal to the gearbox to seamlessly switch off the engine and open the clutch. As the engine is switched off, the car continues to coast and the open clutch limits deceleration.
When the driver pushes the accelerator or engages the clutch to change gear, the system restarts the engine in the driver's selected gear. Electric power provided by the mild-hybrid starter generator and 48V battery instantly brings the engine and transmission up to the correct speed. The development of the transmission was completed at the Hyundai Motor Europe Technical Center in Offenbach, Germany.
"We are always looking at new ways to improve powertrain efficiency and performance, and the iMT is one such innovation," Kia's head of powertrain Dr Michael Winkler said. "An automatic or a double-clutch transmission suits a lot of drivers, but European drivers in particular still love changing gear for themselves. Alongside the increasing demand for electrified models, the iMT is a result of us exploring ways to electrify the 'classic' manual transmission."
Link: https://www.carscoops.com/2020/06/kia-details-clutch-by-wire-manual-gearbox-for-mild-hybrids/
They've managed to make a manual transmission complicated.
If it works as advertised I think it's great! All the benefits of a hybrid for fuel economy but not having to deal with the car not driving properly (too eager to upshift, etc). The driver controls the "gear".
Those repair bills though!!!!!! :mask:
That is utterly pointless... Even worse than auto rev matching manuals
Quote from: CaminoRacer on June 30, 2020, 09:34:18 AM
They've managed to make a manual transmission complicated.
The automated sequential gearbox and DSG already did that.
I don't see the point.
Buyers who want a stick want a god damned stick.
Buyers who don't, don't.
Nobody asked for or wants half a stick.
Quote from: Soup DeVille on July 09, 2020, 07:35:41 AM
I don't see the point.
Buyers who want a stick want a god damned stick.
Buyers who don't, don't.
Nobody asked for or wants half a stick.
It's meant for India, I'm pretty sure. The Indian market Hyundai Venue has the same gearbox. In india, AMT's are super popular because they're cheap to develop. This is basically an AMT without the automatic shifting function.
Quote from: 2o6 on July 09, 2020, 02:03:46 PM
It's meant for India, I'm pretty sure. The Indian market Hyundai Venue has the same gearbox. In india, AMT's are super popular because they're cheap to develop. This is basically an AMT without the automatic shifting function.
The Venue uses a 2-pedal "clutchless" (automatic clutch) manual, not a 3 pedal manual with DBW clutch pedal.
Quote from: Soup DeVille on July 09, 2020, 07:35:41 AM
I don't see the point.
Buyers who want a stick want a god damned stick.
Buyers who don't, don't.
Nobody asked for or wants half a stick.
Yup
Quote from: MX793 on July 09, 2020, 03:23:54 PM
The Venue uses a 2-pedal "clutchless" (automatic clutch) manual, not a 3 pedal manual with DBW clutch pedal.
I should have clarified, I'm pretty sure this system and the one in the Venue is the same. I think the "iMT" (AMT) is just a few extra lines of code, and the clutch pedal omitted for the Indian market.
The European one can unclutch itself if it needs to, I can't imagine why they wouldn't write a bit more code for it to be able to work like an AMT (where you have to shift it)
I guess it would make sense in places like India or even China where a CVT or 4AT would be too expensive or power sapping on a small engine.
Quote from: 2o6 on July 09, 2020, 02:03:46 PM
It's meant for India, I'm pretty sure. The Indian market Hyundai Venue has the same gearbox. In india, AMT's are super popular because they're cheap to develop. This is basically an AMT without the automatic shifting function.
Interesting.
Trying to figure out how these are cheaper to develop than a traditional, planetary gearset slushbox.
Quote from: MX793 on July 09, 2020, 05:25:30 PM
Trying to figure out how these are cheaper to develop than a traditional, planetary gearset slushbox.
Maybe it's an emissions thing? It's probably just easier to put a couple servos on a manual gearbox, rather than develop and tune a CVT or DCT or even regular automatic that can still meet the performance, cost, and emissions parameters. These AMT's are usually on very cheap cars, with very small engines.
Cars like the Suzuki S-Presso, or Tata Tiago only have like 80HP, and are cheap. It's probably much easier and cheaper to hook up a couple servos to the manual gearbox rather than develop an automatic. Especially since it seems like the markets they're sold in don't care too much about particularly smooth shifts.
Quote from: 2o6 on July 09, 2020, 06:05:47 PM
Maybe it's an emissions thing? It's probably just easier to put a couple servos on a manual gearbox, rather than develop and tune a CVT or DCT or even regular automatic that can still meet the performance, cost, and emissions parameters. These AMT's are usually on very cheap cars, with very small engines.
Cars like the Suzuki S-Presso, or Tata Tiago only have like 80HP, and are cheap. It's probably much easier and cheaper to hook up a couple servos to the manual gearbox rather than develop an automatic. Especially since it seems like the markets they're sold in don't care too much about particularly smooth shifts.
Also on big ass Class 8 trucks. I hate them. So slow.
Quote from: 2o6 on July 09, 2020, 06:05:47 PM
Maybe it's an emissions thing? It's probably just easier to put a couple servos on a manual gearbox, rather than develop and tune a CVT or DCT or even regular automatic that can still meet the performance, cost, and emissions parameters. These AMT's are usually on very cheap cars, with very small engines.
Cars like the Suzuki S-Presso, or Tata Tiago only have like 80HP, and are cheap. It's probably much easier and cheaper to hook up a couple servos to the manual gearbox rather than develop an automatic. Especially since it seems like the markets they're sold in don't care too much about particularly smooth shifts.
I think you underestimate the level of sophistication required for automating the actuation of a dry clutch. It's not nearly as simple as "slap a couple of servo motors in there".
With these cheap, low powered cars, they could probably get away with the kind of CVT you find in snowmobiles and ATVs/UTVs. Super cheap to implement and super simple.
If you want to do a manual gearbox that doesn't require you to use a clutch when you come to a stop or crawling through traffic, you can do what several car companies have done over the past 70+ years and put a torque converter in line with the clutch. Maybe step it up to a locking torque converter with some simple logic to lock up above a given speed and unlock when the engine RPM drops near stall speed.
Quote from: MX793 on July 09, 2020, 05:25:30 PM
Trying to figure out how these are cheaper to develop than a traditional, planetary gearset slushbox.
Less parasitic loss, so the engine can be smaller?
Quote from: MX793 on July 09, 2020, 06:20:24 PM
I think you underestimate the level of sophistication required for automating the actuation of a dry clutch. It's not nearly as simple as "slap a couple of servo motors in there".
With these cheap, low powered cars, they could probably get away with the kind of CVT you find in snowmobiles and ATVs/UTVs. Super cheap to implement and super simple.
If you want to do a manual gearbox that doesn't require you to use a clutch when you come to a stop or crawling through traffic, you can do what several car companies have done over the past 70+ years and put a torque converter in line with the clutch. Maybe step it up to a locking torque converter with some simple logic to lock up above a given speed and unlock when the engine RPM drops near stall speed.
But it evidently must not be cheap, or at least work best for that market. Basically every very small, very cheap automatic in India is an AMT, and has been for years. Basically all the Suzuki cars, the Renault Kwid, the Datsun Go, basically all Tata hatchbacks. GM does the same thing for some of their cheaper Baojun vehicles, although lately they've been phased out for CVT automatics (and the price has gone up, too).
Also, they *don't* work that well. They're notorious for being jerky as shit.
I don't understand how developing a torque converter or shift logic for a CVT would be cheaper than automating the clutch and gearchange. These setups are basic, I'm not a 100% sure of the design, but I'm pretty sure what is in essence, a robot that "pushes" the clutch, and another one that changes the gears. Those AMT's share a lot with the regular manual transmissions. I mean, these cars are like $4500 new.
Quote from: Soup DeVille on July 09, 2020, 07:03:42 PM
Less parasitic loss, so the engine can be smaller?
Here's a shitty video for Suzuki's AGS system. It looks like a box bolted to a regular manual.
https://youtu.be/txAdIaXwZuo
Quote from: 2o6 on July 09, 2020, 07:08:17 PM
But it evidently must not be cheap, or at least work best for that market. Basically every very small, very cheap automatic in India is an AMT, and has been for years. Basically all the Suzuki cars, the Renault Kwid, the Datsun Go, basically all Tata hatchbacks. GM does the same thing for some of their cheaper Baojun vehicles, although lately they've been phased out for CVT automatics (and the price has gone up, too).
Also, they *don't* work that well. They're notorious for being jerky as shit.
I don't understand how developing a torque converter or shift logic for a CVT would be cheaper than automating the clutch and gearchange. These setups are basic, I'm not a 100% sure of the design, but I'm pretty sure what is in essence, a robot that "pushes" the clutch, and another one that changes the gears. Those AMT's share a lot with the regular manual transmissions. I mean, these cars are like $4500 new.
You don't need "shift logic" for a basic CVT or even rudimentary auto. Automatic transmissions existed long before cars had ECUs and computers. Shift "logic" was purely mechanical in nature.
Logic for controlling a dry plate clutch and throttle so that the car can take off from a stop without stalling or smoking the clutch is not simple. If it was, we would have seen these gearboxes 50+ years ago. The earliest example I'm aware of to make production came out in the mid 80s and was a flop. The first successful examples came out in the later 90s.
Quote from: 2o6 on July 09, 2020, 07:12:18 PM
Here's a shitty video for Suzuki's AGS system. It looks like a box bolted to a regular manual.
https://youtu.be/txAdIaXwZuo
Pretty neat really, like a little robot doing the work for you.
Quote from: 2o6 on July 09, 2020, 07:12:18 PM
Here's a shitty video for Suzuki's AGS system. It looks like a box bolted to a regular manual.
https://youtu.be/txAdIaXwZuo
Haha that's pretty bad as far as presentation but production of the video isn't too bad. And they definitely make their point- although "fun to drive" doesn't seem a huge selling point, fuel economy, ease of driving, price, and weight all are why they build them.
Quote from: Soup DeVille on July 09, 2020, 07:35:41 AM
I don't see the point.
Buyers who want a stick want a god damned stick.
Buyers who don't, don't.
Nobody asked for or wants half a stick.
Yeah, basically every half measure has been...well, just that.
Quote from: AutobahnSHO on July 10, 2020, 12:45:11 PM
Haha that's pretty bad as far as presentation but production of the video isn't too bad. And they definitely make their point- although "fun to drive" doesn't seem a huge selling point, fuel economy, ease of driving, price, and weight all are why they build them.
I can't imagine much in the way of fuel savings. Automatics are pretty efficient these days if they're programmed for it. My car is pretty good at keeping the rpm down around 1500. As well, with converter locks, not much in the way of slush.