Improving the realism in motion-based driving simulators by adapting tilt-translation technique to human perception

Abstract

While modern dynamic driving simulators equipped with six degrees-of-freedom (6-DOF) hexapods and X-Y platforms have improved realism, mechanical limitations prevent them from offering a fully realistic driving experience. Solutions are often sought in the "washout" algorithm, with linear accelerations simulated by an empirically chosen combination of translation and tilt-coordination, based on the incapacity of otolith organs to distinguish between inclination of the head and linear acceleration. In this study, we investigated the most effective combination of tilt and translation to provide a realistic perception of movement. We tested 3 different braking intensities (deceleration), each with 5 inverse proportional tilt/translation ratios. Subjects evaluated braking intensity using an indirect method corresponding to a 2-Alternative-Forced-Choice Paradigm. We find that perceived intensity of braking depends on the tilt/translation ratio used: for small and average decelerations (0.6 and 1.0m/s 2 ), increased tilt yielded an increased overestimation of braking, inverse proportionally with intensity; for high decelerations (1.4m/s 2 ), on half the conditions braking was overestimated with more tilt than translation and underestimated with more translation than tilt. We define a mathematical function describing the relationship between tilt, translation and the desired level of deceleration, intended as a supplement to motion cueing algorithms, that should improve the realism of driving simulations.

Design and kinematic analysis of a two-DOF moving platform as a base for a car simulator

“…The process of testing the platform is firstly done by performing simulation separately between roll and pitch planes, wherein incremental angle input (𝜃) is fed to (9). The range of angle input (𝜃) is Figure 8.…”

“…Jefiza et al [23] and Al-Dahan et al [24] used the MPU6050 module to detect the fall of the elderly when walking, while Rifajar and Fadlil [25] used it to detect the fall of a dancing robot by monitoring the acceleration of rotational motion. The approach to measuring joint angles in this research is different, where the measured orientation is used to calculate joint angles of the DC actuators based on (9).…”

“…This figure determines the maximum allowable range of rotational motion of the moving platform. Moreover, according to Stratulat et al [9], the limit of the vestibular system for sensing radial velocity is 3.7 deg/s. However, based on research by Groen and Bles [10], the movement of the car simulator will be more realistic when the entire car simulator platform is tilted with a radial speed that does not exceed 3 deg/s.…”

Impact of Human-Centered Vestibular System Model for Motion Control in a Driving Simulator

“…However, if this technique is not correctly implemented, it may generate an inaccurate motion perception, as it does not correspond to a natural driving movement. In addition, other studies have shown that the tilt perception thresholds must be adapted according to the level of acceleration to improve realism [3]. This leads us to believe that some participants may have been influenced not only by the type of model used in each strategy but also by the cueing strategy itself.…”

“…One of the approaches aiming at solving these problems has been to integrate human motion perception into the control design. Most MCAs use human perceptive system information to restore additional linear acceleration while tilting the platform cockpit [3]- [6]. This is a well-known technique named tilt coordination.…”