Stress-free starting

Getting a truck rolling from a standstill up a hill requires agile footwork between the clutch and the accelerator. It can also be tough for the clutch if the rolling resistance is high or the driver misuses the clutch.

As of March 2008, all Scania trucks with clutch pedals are fitted with Scania Launch control, which relieves the driver of the stress of getting a heaving truck moving off up a hill or in the rough.

Scania engineer Per Sundholm developed the new system after studying the calibration of the accelerator pedal during normal driving and during stops.

Software solution

Sundholm found that he could optimise the calibration for each of these functions but not both at the same time, so he created a piece of software that did exactly that.

“Instead of increasing pressure on the accelerator as the clutch is released, the driver only needs to depress the accelerator to the desired engine speed, and Launch control automatically increases the power of the engine to get the torque to start the truck,” says Sundholm.

“It is like an electric radiator in your home,” he explains. “If you want it to be 20 degrees inside and it is cold outside, it will need to deliver more heat to maintain 20 degrees than if it were warm outside.”

Reduced wear and tear

Because Launch Control optimises the engine power according to parameters such as engine speed, accelerator and clutch positions, road speed (in this case zero), temperature and so on, substantial savings in terms of wear and tear can be achieved on, for example, the clutch system.

“Launch control guarantees optimum torque for starting on a hill or with a heavy load,” says Sundholm. “And for the driver, starting at a lower revs makes the truck feel powerful.”

Patent are pending for the new system.