…the flexible open source driving simulation

This task is a rebuilt of the original lane change task SO 26022: Road vehicles. Ergonomic aspects of transport information and control systems. Simulated lane change test to assess in-vehicle secondary task demand (2010). British Standards Institution. You can now use LCT directly in OpenDS and modify it according to your requirements.

The Lane Change Task (LCT) is a ISO-standardized driving task (ISO 17387:2008) that was widely used in automotive human-machine interaction (S. Mattes, 2003). LCT contains driving on a straight road at a fixed speed and requires the driver to continuously change between three lanes accordingly to information presented on road signs. For application, a handbook as well as an analyzer tool is available.


The LCT is an easy-to-implement, low-cost methodology for the evaluation of the distraction associated with performing secondary tasks while driving (Stefan Mattes, 2003). The result is an estimate of secondary task demand. The LCT is a driving task which resembles the visual, cognitive and motor demands of driving.

Principle and overview

The LCT is a simple dual task method that is able to quantify performance losses in a primary task caused by the performance of a secondary task. The primary task requires driving at a constant and limited speed of 60 km/h. Participants are not allowed to reduce speed when they are on the track. Instead, participants should keep the accelerator pedal pressed to the floor the entire time while driving.The simulated road comprises three lanes, which should be changed on occasion. Participants are instructed in which of the lanes they should drive by signs that appear at approximately regular intervals on both sides of the track (cf. Figure 1).

Figure 1. The original Lane Change Task (LCT).

The position of the simulated vehicle can be controlled and changed by means of the steering wheel. The “Lane Change” signs appear in pairs on both sides of the simulated road. The downwards arrow on the signs indicates the target lane. The signs are always visible but blank until the driver is positioned 40 meters in front of the signs. Then, the lane change information appears (cf. Figure 1, the situation on this screenshot indicates a lane change from the middle to the right lane). Participants have to begin a lane change as soon as the symbols appear on a sign. The mean distance from sign to sign is 150 meters. Thereby the mean duration between two changes is about 9 s at a speed of 60 km/h. There are 18 pairs of “Lane Change” signs along a track. Moreover, six different lane changes are possible (from left lane to right lane, from left lane to middle lane, etc.). The number of changes is balanced within 18 pairs of signs. There are 10 different tracks with a length of 3000 m. Due to the fact that speed is specified and limited to 60 km/h a duration of about 180 s per track results. To avoid learning effects, there exist 10 tracks with different order of signs/lane changes.To compare the performance during different runs the mean deviation between the adaptive model path trajectory and the participant’s actual driving path is calculated as the parameter of interest. In our case, the participants were instructed to start the secondary task at the “start” sign und to continue until the investigator stops the simulation at the end of the track.

However, LCT’s validity regarding real-world driving is disputed as there could be, for example, cognitive tunneling effects. Also, the driving task has low flexibility as its tracks are limited to three minutes per drive, fixed speed and fixed timing of events, predictable timing of upcoming events and contains only lane keeping and lane changes. Furthermore, it was designed to serve only for secondary task assessment.

The implementation of LCT in OpenDS is identical with the original version. However, users can decide to carefully change/extend the task and hence overcome some of the above restrictions. 

Figure 2. The Lane Change Task rebuilt in OpenDS.