Adaptive Shift Strategy

Adaptive Shift Strategy
By increasing the linking of the transmission control system with other vehicle systems such as engine, brakes (ABS) and steering, a number of signals are made available to the TCM, which describe how the vehicle is being driven and on what road conditions. Using this information the TCM is able to exploit the vehicle's performance capability, and conversely maximize driving refinement and economy.

By monitoring signals associated to:
- Longitudinal and lateral acceleration,
- Engine speed and engine torque,
- Engine oil temperature,
- Position and movement of the accelerator, and
- Individual wheel speed,

Additional functions in the TCM can be realized. On the basis, of this information the TCM recognizes whether:
- The vehicle is maneuvering round a corner,
- All the wheels are gripping,
- The driver is braking,
- Or if the driver wishes to accelerate.

From these signals, conclusions are made regarding the vehicle's actual load status and the topography of the stretch of road (uphill or downhill gradient), and what shift strategy should be applied to the transmission function. For example, when 'sport' mode is selected and an enthusiastic driving style is detected on a demanding road. The TCM will adjust the transmission shift strategy to complement the conditions by inhibiting sixth-gear and selecting lower gears earlier to prevent 'hunting' between gears.

Under heavy braking, the TCM will select a lower gear to enable an immediate acceleration response on application of the accelerator pedal. Similarly, if the accelerator pedal is released rapidly following hard acceleration, selection of a higher gear is inhibited to increase engine braking and improve subsequent acceleration response. To complement these features, when the TCM detects the vehicle rounding a corner, selection of a higher gear is inhibited until the vehicle exits the corner. Once a more sedate driving style is detected, sixth gear will be reinstated and the shift strategy will return to normal.