This paper describes the experiments involving a driving simulator that examined the implicit relationship
between subjective perception and objective closeness of the gap between the host car and the lead car, the latter closing to the former at a constant relative velocity / at a constant relative deceleration rate. The subjective perception of closeness was quantified in terms of 1/TTC (θ?/θ, where theta is the driver’s visual angle of the lead car). The results suggest that the drivers perceive the lead car closing in terms of 1/TTC both in the constant relative velocity condition and the constant deceleration condition.
This study analyzes the relationship between the time of visual distraction for a driver, which can be defined
as taking one’s eye away from the forward driving view, and the probability of traffic accidents. Using a driving simulator, we investigated the evasive reaction time of 22 drivers to risky events under a visual distraction. We subsequently analyzed the correlation between the evasive reaction time and the occurrence probability of rear-end collision and lane-deviation collision using a statistical probabilistic model, which can quantify the risk of traffic accidents. Based on this relationship, the possibility of reducing the evasive reaction time using a distraction alarm was investigated in order to minimize the probability of collision. The results demonstrate that reducing the distraction time and thus the evasive reaction time below 1.0 s effectively reduced the probability of a rear-end collision to one third compared with the probability without using an alarm system. Moreover, this system was also effective against collisions resulting from lane deviation.
In Japan it is well known that many crossing collisions occur at non-signalized intersections, especially
elderly drivers are responsible for these accidents. Therefore, the traffic circumstance of stop sign intersections, where visibility is bad, was simulated by our highly realistic driving simulator. The visibility distance of the crossing vehicles and the confirmation action to pass through the intersection were evaluated with the time axis and the distance axis. The results found that the left/right safety checks of the elderly drivers were not sufficient. An ideal way of elderly driver's drive assist system was considered from the relation between elderly driver's driving action and accident factors based on these results.
Closed-loop control is vital for an application of HCCI engines in passenger cars. This paper introduces a simplified control-oriented model for control of combustion phasing and IMEP of a Blowdown Supercharge Engine (BDSC). Despite the complexity of this particular engine, the model has been found to match not only the steady state values in high load HCCI, but also to reproduce the transients. This model takes advantage of the knowledge of non-dynamic processes within the engine that can be derived from steady state values, while the main dynamics are achieved by dynamically modelling of cyclic coupling via in-cylinder temperature alone and mean exhaust pressure dynamics. Furthermore, a simplified combustion model has been found to be accurate enough for the region of interest. An automated tuning scheme helps to match the model to the respective target values. With this model and the tuning scheme, the model can be easily tuned for every possible case. A model-based MIMO state controller, based on Sliding-Mode Control theory has been designed and tested on a detailed 1-D simulation code.