Perception of Combined Visual and Inertial Low-Frequency Yaw Motion

AIAA Modeling and Simulation Technologies Conference

et al. 2011

Self Cite

In motion simulation the inertial information generated by the motion platform is most of the times different from the visual information in the simulator displays. This occurs due to the physical limits of the motion platform. However, for small motions that are within the physical limits of the motion platform, one-to-one motion, i.e. visual information equal to inertial information, is possible. It has been shown in previous studies that one-to-one motion is often judged as too strong, causing researchers to lower the inertial amplitude. When trying to measure the optimal inertial gain for a visual amplitude, we found a zone of optimal gains instead of a single value. Such result seems related with the coherence zones that have been measured in flight simulation studies. However, the optimal gain results were never directly related with the coherence zones. In this study we investigated whether the optimal gain measurements are the same as the coherence zone measurements. We also try to infer if the results obtained from the two measurements can be used to differentiate between simulators with different configurations. An experiment was conducted at the NASA Langley Research Center which used both the Cockpit Motion Facility and the Visual Motion Simulator. The results show that the inertial gains obtained with the optimal gain are different than the ones obtained with the coherence zone measurements. The optimal gain is within the coherence zone.The point of mean optimal gain was lower and further away from the one-to-one line than the point of mean coherence. The zone width obtained for the coherence zone measurements was dependent on the visual amplitude and frequency. For the optimal gain, the zone width remained constant when the visual amplitude and frequency were varied. We found no effect of the simulator configuration in both the coherence zone and optimal gain measurements.

supporting

confidence: 76%

Section: Iva Coherence Zone Versus Optimal Gainmentioning

confidence: 99%

Section: Iva Coherence Zone Versus Optimal Gainmentioning

confidence: 99%

See 1 more Smart Citation

Relationship Between Optimal Gain and Coherence Zone in Flight Simulation

Grácio

Pais

AIAA Modeling and Simulation Technologies Conference

et al. 2011

Self Cite

“…For both the upper and the lower threshold measurements only the frequency had a significant effect, with lower values for the higher frequency, similar to what has been seen in previous work. 6,7 The task difficulty did not have a significant effect on the measured thresholds.…”

Section: Iiic Thresholds and Coherence Zonesmentioning

confidence: 98%

“…The CZW also decreases with the decrease in the PMC. The effect of frequency on the PMC has been qualitatively explained 6,7 with the fact that at higher frequencies the dynamics of the Semi-Circular Canals (SCC) have a higher gain in velocity which is not accounted for in the internal comparison of visual and inertial cues. This effect is present in all the threshold measurements indicating that not only for the perception task only, but also for the active tasks, this relationship remains valid.…”

Section: 19mentioning

confidence: 99%

Effect of Performing a Boundary-Avoidance Tracking Task on the Perception of Coherence Between Visual and Inertial Cues

Pais

AIAA Modeling and Simulation Technologies Conference

Wentink

2011

Self Cite

During flight simulation, the inertial and visual stimuli provided to the pilot differ considerably. For successful design of motion cueing algorithms it is necessary to gather knowledge on how pilots perceive the difference between visual and inertial cues. Some of the work done on this topic has concentrated on the concept of coherence zone. A coherence zone represents a range of inertial motion amplitudes, which although not being a match with the visual motion, are still perceived by humans as one realistic, coherent movement. To extend the knowledge on coherence zones an experiment was performed that tested the yaw motion coherence zone limits at two frequencies during passive and active situations. Subjects were required to perform a boundary-avoidance task as a mean to decrease the attention given to the perception task. This decrease in attention was thought to cause a widening of the perceived coherence zones. The boundary-avoidance tracking task had two levels of difficulty. The measured coherence zones did not change significantly with the addition of the control task. These results imply that unlike motion perception thresholds, coherence zones are little influenced by decreased levels of attention. This being true, for a range of tasks, such as supervisory tasks or procedural training in a flight simulator, pilot acceptance of the inertial cues might be measured in a passive manner and directly applied to the active scenario.

Perceptual scaling of visual and inertial cues

Grácio

Bos²,

et al. 2013

Exp Brain Res

In the field of motion-based simulation, it was found that a visual amplitude equal to the inertial amplitude does not always provide the best perceived match between visual and inertial motion. This result is thought to be caused by the "quality" of the motion cues delivered by the simulator motion and visual systems. This paper studies how different visual characteristics, like field of view (FoV) and size and depth cues, influence the scaling between visual and inertial motion in a simulation environment. Subjects were exposed to simulator visuals with different fields of view and different visual scenes and were asked to vary the visual amplitude until it matched the perceived inertial amplitude. This was done for motion profiles in surge, sway, and yaw. Results showed that the subjective visual amplitude was significantly affected by the FoV, visual scene, and degree-of-freedom. When the FoV and visual scene were closer to what one expects in the real world, the scaling between the visual and inertial cues was closer to one. For yaw motion, the subjective visual amplitudes were approximately the same as the real inertial amplitudes, whereas for sway and especially surge, the subjective visual amplitudes were higher than the inertial amplitudes. This study demonstrated that visual characteristics affect the scaling between visual and inertial motion which leads to the hypothesis that this scaling may be a good metric to quantify the effect of different visual properties in motion-based simulation.