Haptic pop-out of movable stimuli

When, in visual and haptic search, a target is easily found among distractors, this is called a pop-out effect. The target feature is then believed to be salient, and the search is performed in a parallel way. We investigated this effect with movable stimuli in a haptic search task. The task was to find a movable ball among anchored distractors or the other way round. Results show that reaction times were independent of the number of distractors if the movable ball was the target but increased with the number of items if the anchored ball was the target. Analysis of hand movements revealed a parallel search strategy, shorter movement paths, a higher average movement speed, and a narrower direction distribution with the movable target, as compared with a more detailed search for an anchored target. Taken together, these results show that a movable object pops out between anchored objects and this indicates that movability is a salient object feature. Vibratory signals resulting from the movable ball were found to be a reasonable explanation regarding the sensation responsible for the pop-out of movability

Using curvature information in haptic shape perception of 3D objects

Are humans able to perceive the circularity of a cylinder that is grasped by the hand? This study presents the findings of an experiment in which cylinders with a circular cross-section had to be distinguished from cylinders with an elliptical cross-section. For comparison, the ability to distinguish a square cuboid from a rectangular cuboid was also investigated. Both elliptical and rectangular shapes can be characterized by the aspect ratio, but elliptical shapes also contain curvature information. We found that an elliptical shape with an aspect ratio of only 1.03 could be distinguished from a circular shape both in static and dynamic touch. However, for a rectangular shape, the aspect ratio needed to be about 1.11 for dynamic touch and 1.15 for static touch in order to be discernible from a square shape. We conclude that curvature information can be employed in a reliable and efficient manner in the perception of 3D shapes by touch

"Haptic material": A Holistic Approach for Haptic Texture Mapping

International audienceIn this paper, we propose a new format for haptic texture mapping which is not dependent on the haptic rendering setup hardware. Our "haptic material" format encodes ten elementary haptic features in dedicated maps, similarly to "materials" used in computer graphics. These ten different features enable the expression of compliance, surface geometry and friction attributes through vibratory, cutaneous and kinesthetic cues, as well as thermal rendering. The diversity of haptic data allows various hardware to share this single format, each of them selecting which features to render depending on its capabilities

A comparative survey of climbing robots and arboreal animals in scaling complex environments

© Springer Nature Switzerland AG 2019. The inchworm-style climbing robot present in current literature will only take us so far towards the robotic maintenance of transmission towers. To continue to push toward developing robots that can perform work in reticular structures we must consider a broader spectrum of animals for inspiration. The abilities of Primates in climbing have long been a benchmark in climbing standards, but due to the mechanical and control complexity associated with their development, they are seldom seen in robotics. Birds (specifically Psittaciformes) offer an alternate solution, utilising less degrees-of-freedom whilst maintaining stability and maneuverability. These ancient arboreal specialists may hold they keys to unlocking the next stage in the development of climbing robotics. This work presents lessons learned from a review on primates as well as some preliminary observations on the climbing capabilities of Psittaciformes