Developing Enthusiast Features for Driveline Control in a Volvo car

Abstract

When the new Volvo S/V60 was released it was marketed as a sporty and dynamic car. The chassis and handling of the car makes it enjoyable and it communicates in a direct fashion with the driver which is greatly appreciated by journalists and enthusiast car drivers. The great reception of the car encouraged to investigate what that could be done within driveline control in order to make it even more fun to drive. In this thesis the following enthusiast features are developed and tested: Launch control, down shift support, controlled exhaust detonations during shifts, injection cuts for sound and response reasons, distinct/sporty accelerator pedal characteristics in neutral and a system for increasing the response of the engine after gear change. All features are implemented within the engine controller. Models for the new functionality were developed in Matlab/Simulink. The launch control was simulated using VSim, a Volvo developed tool for longitudinal vehicle analyses. For the functionalities not well represented by VSim, measurement data from the test vehicle was run through the models to verify that the output signals were correct. The Simulink models were then adapted to the ECM and implemented into a test vehicle. The test vehicle used was a Volvo S80 with a 2.5 liter turbocharged port fuel injected five cylinder engine, manual transmission and a Denso ECM. The testing and calibration was conducted on test tracks, regular roads and in a chassis dynamometer. The result of the addition of new features is a car that is more fun to drive, offers quicker acceleration, better response and gives a more direct and sporty impression. Use of launch control gives quick and repetitive 0-100km/h times. The time to regain boost after gear change is reduced by 0.3 seconds and boost pressure never drops below 160kPa absolute pressure with the response system active. The "Skip stroke" injection cut strategy proved to be useful for building torque reserves with very moderate exhaust temperatures. The down shift support gives a smoother and more stable ride while letting the driver impress his friends with his down shifting skills. The sportier accelerator pedal characteristics proved to make the communication between car and driver feel more direct and finally the addition of exhaust detonations during gear changes makes it impossible not to smile.