Sensodrive gearbox

An electronically controlled manual gearbox, the SensoDrive features electronically managed clutch and gear-shift functions. As a result, the car has no clutch pedal and the gear lever — which remains present — has no mechanical link with the gearbox.

The SensoDrive gearbox is managed by a control unit, which controls two actuators. One actuator changes gears while the other, which is equipped with a facing wear compensation system, opens and closes the clutch. The gearbox control unit also dialogues with the engine control unit.

The SensoDrive gearbox is managed by a control unit, which controls two actuators. One actuator changes gears while the other, which is equipped with a facing wear compensation system, opens and closes the clutch. The gearbox control unit also dialogues with the engine control unit.

This sophisticated electronic management system takes into account all the parameters necessary for efficient gear-changing: gear lever, accelerator, brake, engine and gearbox rpm, vehicle speed, ABS, ESP, engine torque and temperature. In this way, when the gearbox control unit receives an order — in either operating mode — to change speeds, it briefly cuts off the engine’s powerflow, disengages the clutch, changes gears, engages the clutch and authorises power to be restored. These operations are sequenced as quickly as possible to minimise the break in acceleration.

For vehicle start-up, the gearbox control unit closes the clutch in accordance with the accelerator position and the engine speed. With this high-precision servosystem, the driver remains in full control of the car in the most difficult situations (reverse parking, hillstarts) as well as on fast starts.

Steering wheel - mounted paddle (+)
In automatic mode, gears are selected by the computer on the basis of the auto-adaptive shift patterns.

The control unit analyses the driver’s behaviour and the type of route (rising, falling, corner) as well as the vehicle load and surface grip in order to define the most appropriate gear speed.

The SensoDrive gearbox reaps the benefits of the experience acquired by PSA Peugeot Citroën with the auto-adaptive gearbox.

To avoid changing gears too frequently, gear shifts are conducted at different speeds during acceleration and deceleration.

The SensoDrive features two operating modes:

• manual mode
• automatic mode
• In manual mode, the driver maintains full control over gear shifts. Gears are changed using one of the two control functions provided.
  
  Paddles located behind the wheel. The right-hand paddle is used to change up, the left-hand paddle to change down. These paddles give access to the five forward speeds. Their position in relation to the wheel is fixed, so they can be used intuitively by the driver whatever the wheel position, for improved comfort and safety.
• A gear lever on the central console. This lever has a stable central position. The driver pushes it forwards (+) to change up, and pulls it back (-) to change down.

For reasons of safety, only the console lever can be used to put the car into neutral or reverse. The driver pushes the lever to the right to put the car into neutral. To put the car into reverse, the driver places a foot on the brake pedal, pushes the lever right andpulls it back.

Even when manual mode is active, the SensoDrive gearbox enhances driving comfort. For example, the driver no longer has to change down on braking, when the car is approaching a stop sign or traffic lights. The gearbox changes down to first gear automatically then disengages the clutch when the car stops. When the driver puts a foot on the accelerator to move off again after a brief stop, the car starts up in first gear.

Moreover, in order to protect the power train, each request to change gears is analysed by a computer, which validates or rejects the driver’s actions and can even select the appropriate gear in the event of overor under-revving.

Last, the gearbox control unit makes down-shifting a smooth and gentle process.

In automatic mode, the driver delegates the decision and the selection of gears to the control unit, which applies a number of gearshift patterns managed on an auto-adaptive basis.

The control unit analyses the driver’s behaviour, the type of route and the position of the accelerator in order to define the most appropriate gear.

The control unit applies a number of rules in specific situations: maintain the current gear speed or change down to boost engine brake power; refuse change-ups on corners; change down to the lowest gear on kick-down for power acceleration.

In the same way, the gearbox detects low-grip conditions and adopts a “snow” type programme. This information is displayed on the instrument cluster.

An electric control function positioned on the central console behind the lever lets the driver switch to automatic mode. In this case, an “Auto” pictogram is displayed on the instrument cluster, together with the gear engaged. At the same time, an indicator lights up.

To ensure maximum safety, the SensoDrive gearbox includes a number of protective functions:

The engine will only start if the brake pedal is pressed down.

The driver can put the car into reverse only if his foot is on the brake and the car is stationary.

If the car remains stationary over a long period with the engine on and a gear selected, the system returns automatically to neutral.

The technology of the SensoDrive gearbox brings improvements in many areas:

• Comfort : In automatic mode, the driver does not have to change gears: a major advantage in heavy traffic. In manual mode, the driver no longer has to take a hand off the wheel to select the gear required.
• Safety : Eyes on the road and hands on the wheel, the driver concentrates on the road ahead. A dashboard indicator shows the current gear-speed and mode of operation.
• Consumption : Automatic mode optimises gear shift management to bring savings of 0.2 l/100 km in a standard combined cycle.

* The technology featured on this website may vary in availability from one model to another.