1. Shaping the Future Transmission Systems

2. Transmission Gear Changing (Shifting) Automated Manual Transmissions Continuously Variable Transmissions Infinitely Variable Transmissions

3. Transmissions – Shift Perception

4. Transmissions – Shift Times

5. Transmissions – Shift Time Profile Longitudinal Acceleration (g) Time (seconds)

6. Oscillation start up during torque re- instatement is caused by combined engine torque modulation and clutch actuation and is strongly affected by the clutch performance model plus knowledge of temperature dependent friction characteristics  Oscillation continuation is due to lack of driveline damping – not apparent on AT systems (due to torque converter)  Rapid rates of torque reinstatement lead to shorter shift times but can result in higher post shift oscillations Transmissions – Shift Time Profile

7. Oscillation start up during torque re- instatement is caused by combined engine torque modulation and clutch actuation and is strongly affected by the clutch performance model plus knowledge of temperature dependent friction characteristics  Oscillation continuation is due to lack of driveline damping – not apparent on AT systems (due to torque converter)  Rapid rates of torque reinstatement lead to shorter shift times but can result in higher post shift oscillations Transmissions – Shift Time Profile

8. Time (seconds) Longitudinal Acceleration (g) Transmissions – Shift Time Profile

9. Shift by Wire and Automated Manual Transmissions

10. Second generation systems (AMT); Twin clutch, Twin layshaft Gear pre-selection Single cone synchros Hydraulic shift action and clutch control First generation systems were based on former manual shift systems (SbW); Usually single dry clutch systems with hydraulic and electro hydraulic actuations Primary applications, small city vehicles (high shift operation) Poor torque interrupt effects and poor clutch thermal performance

11. First Generation AMT Aisin Seiki

12. 2 nd Generation AMT Getrag Powershift (Ford, Volvo) > Dual Clutch > Hydraulic Actuation > 10% fuel economy benefit (on Auto)

13. Automated Manual Transmissions

14. Automated Manual Transmissions – Shift Perception  Unlike the conventional mechanical system the feel of the shift change (the tactile feedback) can be almost exactly defined within the context of the chosen control system, whether that is the a steering wheel paddle system or an artificial shift level  In the case of the shift level it is usual to include either a mechanical H type – so replicating a manual system or adopt the step-up/step-down convention often used on barrel change systems (e.g motorbikes)  The removal of the gear shift cable associated NVH issues is a major advantage of AMT systems from a ‘pleasibility’ standpoint. The driver is very sensitive to all in-cabin noises and vibrations, particularly those low frequency harmonics associated with the powertrain

15. Variable Transmissions

16. Continuous change in output to input ratio – NOT discrete ratios Ability to transmit power throughout during ratio change CVT (Continuously Variable Transmission) Has maximum and minimum ratio limits Two main families of mechanical CVT > Variable pulley drives > Rolling contact traction drives IVT (Infinitely Variable Transmission) Include within the ratio range a condition with zero output speed whilst the input is rotating (geared neutral)

17. Advantages No gear shift Continuous transmission of torque Control of engine speed independently of vehicle speed Ability to operate engine at peak power over wider range of vehicle speeds Ability to operate at most fuel efficient point for required output power CVT and IVT Disadvantages Mechanical efficiency of ‘variator’ and belts Parasitic efficiency of transmission system and controller Compromise between fuel economy and torque margin to achieve driveability

18. CVT – Variable Pulley

19. Primary pulley position sets ratio Secondary pressure sets torque level CVT – Pulley Operation

20. CVT – Variable Pulley

21. Audi A6 2.8L Multitronic CVT – Variable Pulley

22. Ratio spread 6,0 Consumption 9% less than 5- speed-automatic Engine torque 310 Nm Audi A6 2.8L Multitronic CVT – Variable Pulley

23. CVT – Control; Strategies Variogram

24. A – engine idle For light acceleration: B – clutch engagement; C to D – constant engine speed and ratio change with vehicle acceleration; D to E – increased engine speed at constant ratio. Variogram CVT – Control; Strategies

25. Kickdown: G- clutch engagement; G to H – engine acceleration to maximum speed; H to F vehicle acceleration with maximum power. Variogram CVT – Control; Strategies

26. Full toroidal, traction drive variator – Fast dynamic response – Torque controlled Split power path with epicyclic summing gear – Reverse, forward and ‘geared neutral’ operation without start- up device Twin regime operation – Wide ratio spread IVT – Torotrak

27. 1 The input disc(s) Powered by the engine 2 The variator roller(s) which picks up the power and transfers it to… 3 The output disc(s) which transmits the power to the drive shaft IVT – Torotrak

29. IVT - Series III Layout Power recirculation Low regime; -6 to +15 mph/1000rpm (including geared neutral)

30. IVT - Series III Layout High regime +15 to +74 mph/1000rpm (sync. to overdrive)

31. IVT – Torotrak

32. Standard Auto Transmission - Engine Operating Envelope – US Highway IVT – Fuel Economy Optimisation

33. IVT - Engine Operating Envelope – US Highway Cycle IVT – Fuel Economy Optimisation

34.  Driveability is key to customer acceptance  Calibration is key to driveability solutions  Integrated approach to total powertrain calibration is required  Question mark regarding long term implementation CVT - IVT Conclusions

35. Thank you for listening