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Vibrating Makes for Better Seeing: From the Fly's Micro-Eye Movements to Hyperacute Visual Sensors.

Viollet S - Front Bioeng Biotechnol (2014)

Bottom Line: Several robotic platforms have been endowed with artificial visual sensors performing periodic micro-scanning movements.Artificial eyes performing these active retinal micro-movements have some extremely interesting properties, such as hyperacuity and the ability to detect very slow movements (motion hyperacuity).The fundamental role of miniature eye movements still remains to be described in detail, but several studies on natural and artificial eyes have advanced considerably toward this goal.

View Article: PubMed Central - PubMed

Affiliation: Aix-Marseille University, CNRS, ISM UMR 7287 , Marseille , France.

ABSTRACT
Active vision means that visual perception not only depends closely on the subject's own movements, but that these movements actually contribute to the visual perceptual processes. Vertebrates' and invertebrates' eye movements are probably part of an active visual process, but their exact role still remains to be determined. In this paper, studies on the retinal micro-movements occurring in the compound eye of the fly are reviewed. Several authors have located and identified the muscles involved in these small retinal movements. Others have established that these retinal micro-movements occur in walking and flying flies, but their exact functional role still remains to be determined. Many robotic studies have been performed in which animals' (flies' and spiders') miniature eye movements have been modeled, simulated, and even implemented mechanically. Several robotic platforms have been endowed with artificial visual sensors performing periodic micro-scanning movements. Artificial eyes performing these active retinal micro-movements have some extremely interesting properties, such as hyperacuity and the ability to detect very slow movements (motion hyperacuity). The fundamental role of miniature eye movements still remains to be described in detail, but several studies on natural and artificial eyes have advanced considerably toward this goal.

No MeSH data available.


Related in: MedlinePlus

(A) Simplified diagram of a fixed fly walking on a track ball while its MOT response to the laterally to-and-fro moving target placed in front of it is recorded. (B) Closed-loop control of the target’s speed depending on the MOT activity. If the MOT control system is correlated with the speed of the target, then the latter will remain stationary regardless of the speed reference input signal. In the closed-loop scheme presented here, a second feedback-loop has been added to that proposed by Northrop and Qi (see Figure 3): in this case, the input signal is the target speed and the output signal is the angular speed of the visual axes. The switch makes it possible to open or close the feedback loop, depending on the experimental procedure used.
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Figure 6: (A) Simplified diagram of a fixed fly walking on a track ball while its MOT response to the laterally to-and-fro moving target placed in front of it is recorded. (B) Closed-loop control of the target’s speed depending on the MOT activity. If the MOT control system is correlated with the speed of the target, then the latter will remain stationary regardless of the speed reference input signal. In the closed-loop scheme presented here, a second feedback-loop has been added to that proposed by Northrop and Qi (see Figure 3): in this case, the input signal is the target speed and the output signal is the angular speed of the visual axes. The switch makes it possible to open or close the feedback loop, depending on the experimental procedure used.

Mentions: It would be interesting to check the MOT responses of a fixed walking fly placed in front of a moving target, the linear position of which is controlled in a closed-loop mode (see Figure 6). As described by Northrop and Qi (Northrop, 2001), a target moving laterally to-and-fro in front of a walking fly triggers MOT activity, which is correlated with the speed of the target. Under the closed-loop conditions presented in Figure 6B, the target’s motion will be controlled by the error between a reference input signal (a sinusoidal signal, for example) and the angular speed of the visual axes estimated by recording the MOT activity. Therefore, if the rotation of the visual axes faithfully follows the motion imposed on the target, the feedback loop controlling the speed described in Figure 6B will completely immobilize the target. It is assumed here that the MOT activity is scaled to match the angular speed of the visual axes. This scaling can be applied via the DPP. It is also assumed that the time required to make the target move in response to any change in the MOT activity is very short.


Vibrating Makes for Better Seeing: From the Fly's Micro-Eye Movements to Hyperacute Visual Sensors.

Viollet S - Front Bioeng Biotechnol (2014)

(A) Simplified diagram of a fixed fly walking on a track ball while its MOT response to the laterally to-and-fro moving target placed in front of it is recorded. (B) Closed-loop control of the target’s speed depending on the MOT activity. If the MOT control system is correlated with the speed of the target, then the latter will remain stationary regardless of the speed reference input signal. In the closed-loop scheme presented here, a second feedback-loop has been added to that proposed by Northrop and Qi (see Figure 3): in this case, the input signal is the target speed and the output signal is the angular speed of the visual axes. The switch makes it possible to open or close the feedback loop, depending on the experimental procedure used.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4126468&req=5

Figure 6: (A) Simplified diagram of a fixed fly walking on a track ball while its MOT response to the laterally to-and-fro moving target placed in front of it is recorded. (B) Closed-loop control of the target’s speed depending on the MOT activity. If the MOT control system is correlated with the speed of the target, then the latter will remain stationary regardless of the speed reference input signal. In the closed-loop scheme presented here, a second feedback-loop has been added to that proposed by Northrop and Qi (see Figure 3): in this case, the input signal is the target speed and the output signal is the angular speed of the visual axes. The switch makes it possible to open or close the feedback loop, depending on the experimental procedure used.
Mentions: It would be interesting to check the MOT responses of a fixed walking fly placed in front of a moving target, the linear position of which is controlled in a closed-loop mode (see Figure 6). As described by Northrop and Qi (Northrop, 2001), a target moving laterally to-and-fro in front of a walking fly triggers MOT activity, which is correlated with the speed of the target. Under the closed-loop conditions presented in Figure 6B, the target’s motion will be controlled by the error between a reference input signal (a sinusoidal signal, for example) and the angular speed of the visual axes estimated by recording the MOT activity. Therefore, if the rotation of the visual axes faithfully follows the motion imposed on the target, the feedback loop controlling the speed described in Figure 6B will completely immobilize the target. It is assumed here that the MOT activity is scaled to match the angular speed of the visual axes. This scaling can be applied via the DPP. It is also assumed that the time required to make the target move in response to any change in the MOT activity is very short.

Bottom Line: Several robotic platforms have been endowed with artificial visual sensors performing periodic micro-scanning movements.Artificial eyes performing these active retinal micro-movements have some extremely interesting properties, such as hyperacuity and the ability to detect very slow movements (motion hyperacuity).The fundamental role of miniature eye movements still remains to be described in detail, but several studies on natural and artificial eyes have advanced considerably toward this goal.

View Article: PubMed Central - PubMed

Affiliation: Aix-Marseille University, CNRS, ISM UMR 7287 , Marseille , France.

ABSTRACT
Active vision means that visual perception not only depends closely on the subject's own movements, but that these movements actually contribute to the visual perceptual processes. Vertebrates' and invertebrates' eye movements are probably part of an active visual process, but their exact role still remains to be determined. In this paper, studies on the retinal micro-movements occurring in the compound eye of the fly are reviewed. Several authors have located and identified the muscles involved in these small retinal movements. Others have established that these retinal micro-movements occur in walking and flying flies, but their exact functional role still remains to be determined. Many robotic studies have been performed in which animals' (flies' and spiders') miniature eye movements have been modeled, simulated, and even implemented mechanically. Several robotic platforms have been endowed with artificial visual sensors performing periodic micro-scanning movements. Artificial eyes performing these active retinal micro-movements have some extremely interesting properties, such as hyperacuity and the ability to detect very slow movements (motion hyperacuity). The fundamental role of miniature eye movements still remains to be described in detail, but several studies on natural and artificial eyes have advanced considerably toward this goal.

No MeSH data available.


Related in: MedlinePlus