Compared to cars designed in the 80ies or in the early 90ies, new cars exhibit major improvements, especially in terms of driver assistance and road handling. To quantify the influence of these developments on drivers' behavior, a study was carried out on a test track with two cars of different generations in the summer 2004.

36 male drivers, from 28 to 52 years old, were recruited in the general public to participate to the experiment. They were dispatched in two homogenous groups. For each group, drivers were asked to drive twice the same car:​ the first time, they familiarized freely with the car and the road during about one hour ("free driving phase");​ three weeks later, they were invited to drive on the same road as if they were late or in a hurry ("rush driving phase"). The track is divided in two portions:​ a "main road" (3.5 km) and a "secondary sinuous road" (1.9 km). There is no traffic on the test track. Drivers' actions on the car’s controls were recorded and synchronized with dynamic parameters and video recordings.

This paper is focused on the influence of car modernity and driving consigns on longitudinal and lateral solicitations of the car. Driver's behavior is analyzed in terms of longitudinal acceleration, deceleration (braking) and lateral acceleration when negotiating short curves.