Kia has unveiled more details of its new intelligent Manual Transmission (iMT), which has been designed for the brand’s upcoming mild-hybrid electric vehicles (MHEVs).
The ‘clutch-by-wire’ system is engineered to boost fuel efficiency and reduce CO2 emissions while retaining the driver engagement of a conventional manual transmission.
Instead of being mechanically linked and using hydraulic pressure – Kia’s iMT clutch operates purely electronically and is integrated seamlessly with a 48V mild-hybrid powertrain. The iMT works with the mild-hybrid starter-generator (MHSG) to switch off the engine earlier than the vehicle’s start-stop system when coasting to a halt.
The chosen gear remains engaged even with the engine off. The engine restarts in the same gear as soon as the driver presses either the brake or accelerator pedal thanks to the burst of power provided by the MHSG.
The transmission restarts the engine in neutral (with an open clutch) if the driver pushes the clutch pedal to change gear, or if the vehicle speed is too low for the current engaged gear.
Kia claims the iMT will improve overall fuel efficiency and reduce CO2 emissions by around three percent in real-world driving conditions.
How it works – step-by-step:
- The driver leaves the car in-gear as it starts to coast, gently slowing the car down (e.g. for a corner, junction, or for traffic).
- While in-gear, the iMT sends an electronic signal to the gearbox and MHSG to seamlessly switch off the engine and open the clutch.
- With the engine switched off, and the transmission disconnected by the open clutch, the car is allowed to coast along to make the most of its kinetic energy.
- As the driver pushes the accelerator to pick up speed, or engages the clutch to change gear, the MHSG restarts the engine in the driver’s selected gear, or in neutral (with an open clutch).
- Electric power from the MHSG and 48V battery instantly bring the engine and transmission up to the correct speed.
- If the car drops below a certain speed, such that it is too low for the engaged gear – the engine restarts with assistance from the mild-hybrid system, and the clutch closes, to avoid labouring the engine in the engaged gear
Although it might be difficult to imagine this without a visual representation, Kia claims that the iMT retains the same operation and driver engagement as a conventional manual.
The new system allows drivers to enjoy the uniquely engaging drive that comes from using a manual transmission. The clutch pedal operates in the same manner as a conventional manual, with greater controllability due to the electromechanical control of the clutch and a ‘biting point’ that enables drivers to change gears smoothly.
The iMT is being developed at the Hyundai Motor Europe Technical Centre in Offenbach, Germany, overseen by Dr Michael Winkler, who added, “An automatic or a dual-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.”
Kia’s new iMT will be first introduced in the 2020 Kia Rio EcoDynamics+, due on sale in Europe in Q3 of 2020 with a new 1.0-litre T-GDi petrol mild-hybrid powertrain.
The new transmission will be adopted across a number of future Kia models, with the brand set to introduce a range of new engines and MHEV powertrains later in 2020.