Auditory and haptic systems for in-car speed management – A comparative real life study

Field experiments with ISA (intelligent speed adaptation) were carried out in Hungary and Spain in 2003 and 2004, respectively. Twenty private vehicles in each country were equipped with two kinds of systems: (1) support via an active accelerator pedal (AAP) and (2) warning via beep signals and a flashing red light when the speed limit was exceeded (BEEP). The test drivers drove for a month with both systems installed in each car. Speed was continually logged in all the vehicles and the test drivers were interviewed about their acceptance and experiences of the systems. The results show that both systems reduced the mean and 85 percentile speeds, but that the AAP was more effective. There was no long-lasting effect on speeds when the systems were removed. After the trial half of the drivers were willing to keep an ISA system, but more drivers wanted to keep the BEEP-system even though it showed lower satisfaction ratings than the AAP. The results indicate no major differences between the countries despite the workload being perceived to be higher in Hungary than in Spain.