Pigeons were tested in a search task on the surface of a monitor on which their responses were registered by a touch-sensitive device. A graphic landmark array was presented consisting of a square outline (the frame) and a colored "landmark." The unmarked goal, pecks at which produced reward, was located near the center of one edge of the frame, and the landmark was near it. The entire array wa...

This paper presents a novel landmark generating method for robust multi-robot localization and tracking. Although the conventional approaches are able to generate a number of landmarks, they often tend to misjudge or ignore some landmark in particular environment. Analyzing those methods, we suggest the new landmark that is referred to here as Rotating Triangles (RT) landmark. RT landmark imple...

Route directions describe the sequence of actions a moving person needs to take to reach a goal in an environment. When generating directions, speakers not only specify what to do. They also refer to landmarks located along the route. We report two studies intended to identify the cognitive functions of landmarks. In the first study, participants learned a route in an urban environment. They th...

Twenty outpatients who fulfilled the criteria for a diagnosis of schizophrenia and 28 control participants were invited to learn a route through a complex outdoor environment. They were then tested in tasks intended to explore various aspects of their memorized representation of the navigational episode. Compared to controls, the patients showed significant impairment in both the verbal product...

Active Shape Models often require a considerable number of training samples and landmark points on each sample, in order to be efficient in practice. We introduce the Fractal Active Shape Models, an extension of Active Shape Models using fractal interpolation, in order to surmount these limitations. They require a considerably smaller number of landmark points to be determined and a smaller num...

Teams of humans and robots working together can provide effective solutions to problems. In such applications, effective human-robot teaming relies on being able to communicate information about the current perception or understanding of the environment. In this paper, human-robot teaming on navigational tasks is discussed. The role of the human user will be to specify the goal point(s) for the...

How do honeybees use visual odometry and goal-defining landmarks to guide food search? In one experiment, bees were trained to forage in an optic-flow-rich tunnel with a landmark positioned directly above the feeder. Subsequent food-search tests indicated that bees searched much more accurately when both odometric and landmark cues were available than when only odometry was available. When the ...

This paper investigates the function and formation of spatial language involving landmarks. We argue for two points. First, landmarks have an important function in spatial language. Agents that can use different landmarks and express their choice perform better than agents who cannot. Second, the use of landmarks has a positive effect on evolving systems of spatial relations. Agents that have t...

We propose the novel approach of dynamic affine-invariant shape-appearance model (Aff-SAM) and employ it for handshape classification and sign recognition in sign language (SL) videos. AffSAM offers a compact and descriptive representation of hand configurations as well as regularized model-fitting, assisting hand tracking and extracting handshape features. We construct SA images representing t...