What is iMT - smart manual transmission?

Manufacturers Kia and Hyundai have begun to equip some of their hybrids recently released with an updated gearbox, abbreviated as iMT (intelligent Manual Transmission), which means “intelligent mechanical transmission”. What is this system, what is the use of it? It is worth considering in more detail.

Design

"Smart mechanics" iMT allows you to shift gears in the usual way, using the pedal (it may not be) and the gearshift lever. However, it does not act on the transmission in the usual way through a cable or hydraulics. In this case, the control unit receives a signal due to which the ECU affects the actuator (iMT electronic unit). And already he creates pressure in the hydraulic system. As a result, the rod of the working cylinder comes into motion and the clutch opens. All this happens literally instantly!

Why did it have to be so complicated? The reason is the MHEV (moderate system) hybrid powertrain, which has a 48 volt starter-alternator. Under certain conditions, the electronics disconnect or connect the engine to the transmission on their own, without any action from the driver.

iMT Operation and Practical Benefits

One of the main components of the mild hybrid MHEV is a starter-generator called MHSG (Mild-Hybrid Starter-Generator) and driven by a belt drive. During acceleration, this node adds energy to the internal combustion engine, improving dynamics. In the event of braking or speed reduction, it works like a conventional generator, "collecting" energy into the battery using the recuperation method. Without such a technical solution, efficient start-stop operation would be impossible. Under normal conditions, the start-stop system cannot turn off the powertrain until the driver has shifted into neutral. And in the case of using iMT, the electronics turn off the motor already when the speed slows down. For example, when the car is just “going to” stop (before a traffic light, a pedestrian “zebra”, etc.). Some automatic and robotic transmissions have a similar “skill”, but in this case, “mechanics” are used.





What happens next? As soon as the driver presses the gas, the starter-alternator automatically connects the transmission to the engine. But there are nuances: the transmission will be the same as it was: in order to prevent a “peck”, the electronics will increase the speed in advance. If it decides that the speed is too low, the clutch will remain open and the car will “wait” for the driver to select the desired gear. The engine will start while the car is moving when you press any of the three pedals again (there may be two of them).



A variant of the iMT manual transmission has expanded its capabilities when used in hybrid vehicles. It is worth noting: in terms of design, an electronic clutch system is much simpler than a “robot” and also cheaper. To integrate it, it is enough to install an actuator (sometimes called an “intention sensor”) in a 6-speed manual transmission. It will act on the clutch servo when the shift lever is moved.



For example, Indian buyers of the Hyundai Venue crossover (in the database comes with the usual "mechanics") are offered a car with iMT, subject to an additional payment of 19 thousand rubles. with Russian money. If you need a car with a seven-band “robot” and a pair of clutches, you will have to pay another 109 thousand rubles. Which companies use iMT today?

Hyundai and Kia

This is an updated i30 and "Rio", designed for the European market. In the first case, iMT can be installed on a hatchback, station wagon or fastback, if the car has a 48-volt hybrid system. The most powerful engine in 160 liters. With. equipped with it by default. In Russia, only this version is sold, with a two-liter engine.



The European version of the Kia Rio received an EcoDynamics + hybrid engine, which works in conjunction with a 48-volt starter-generator. As a result, fuel is saved and harmful emissions are reduced by an average of 10%.

2016 Toyota CH-R

According to the description, the use of iMT in the transmission of this machine allows you to avoid jerks, jerks when switching speeds, which are allowed by inexperienced drivers. For example, if an overdrive gear is engaged, the system prevents the engine speed from dropping. And vice versa: when the reduced speed is activated, the iMT “give on to the gas”. If the clutch pedal is held down too long, the system is disabled. However, you should not constantly rely on a modified transmission - this is reminiscent of the instructions for the car:

• ? iMT cannot prevent errors in case of incorrect gear selection or excessive crankshaft revolutions.
  
• ? depending on the specific situation, the system may not function correctly: in order to prevent an accident or rapid wear of transmission parts, you should not rely entirely on iMT
  

Variants of the MHEV with conventional robots are also being produced. The fact is that many automakers quite rightly believe that most drivers want to "personally" shift gears. This “desire” is especially strong in Europe. It is appropriate to recall here - the idea does not shine with novelty.

Clutch automation in other types of transmissions

Toyota has its own iMT, but in this case, the Japanese mean something else. Here is a conventional six-speed manual transmission and a classic clutch. However, when shifting from a lower gear to a higher one or vice versa, the electronics come into action, which additionally adjusts the engine speed to the desired amount. As a result, the speed turns on smoothly.

Citroen DS, released already in 1955, also had a prototype of the current iMT: a four-speed semi-automatic played the role of a transmission. The speeds were switched by a lever on the steering column, but there was no clutch pedal: the driver released the gas, engaged the gear and pressed the pedal again.



All actions were performed by automation - a controller that affects the hydraulic drive. If it was necessary to stop, the driver pressed the brake, the clutch "self" disconnected. As soon as the pedal was released, it turned on and the car went on. There are other examples of machines with a system similar to iMT:

• ✅ VW Autostick - this transmission has been installed since 1968 on the "Beetles" for 8 years: the clutch was activated by pressing the button located at the top of the gearshift handle
  
• ✅ Alfa Romeo Q-System (1998) was a universal transmission - when the lever was moved to a certain position, the usual “automatic” began to work like a manual transmission
  
• ✅ Saab Sensonic - the system was used in Swedish cars until 1998 thanks to the use of a microprocessor that determined the optimal moment for gear shifting
  

The above examples indicate that in the future, most likely, there will be no concept of only two types of transmissions - mechanical and automatic, since many other, more efficient and convenient systems will appear.