Most mobile robot mapping and exploration research makes use of longrange, powerful sensors such as laser rangefinders to create maps. In this paper we take a different approach, creating maps using robots with limited sensing capabilities, most notably in their sensor range. Our prototype robots use only five infrared range sensors with a maximum range of 80 cm; in general, these robots cannot...

Walking requires the coordination of several tasks, including making forward progress (by prodUcing a gait) and maintaining upright posture. In this chapter we discuss how a dynamical model of this coordination can be constructed. Experimentally, subjects walked on a treadmill while viewing large-field visual displays of an oscillating hallway. In our modeling, we focus on two features of the d...

Tucked away somewhere in the twisting innards of Mulago Hospital, Kampala, Uganda, there lies the pink, neatly stapled medical file of a man who is doomed to die. I know this because I saw him on Thursday night. “There’s an interesting case you should see if you have time,” said the attending physician cheerily. “You should look up his condition in your book and take a history. It might be good...

Ubiquitous computing is making it possible to increase the sensory feedback from everyday spaces to attract attention to often-neglected tasks, make them safer and easier and potentially motivate new behavior. HyperReality describes distributed computing interfaces that weave existing environments with immersive sound and images to expand sensory feedback from everyday activities. This paper di...

Et Tu, Torsten? This critique of my Economic Policy paper generates many emotions. It is certainly an honor for my research to be taken seriously by such an eminent scholar as my friend Torsten Persson. And while any publicity is good, a negative citation dominates a positive one. There is irony; I came up with the original idea in a hallway conversation with Harry Flam a few feet from Persson’...

In a number of studies reaction time has been found to increase with increases in size ratio on a same -different form-comparison task. Bennett and Warren (2002, Perception & Psychophysics 64 462-477) teased apart environmental and retinal size ratios by showing the forms along a (simulated) texture hallway, viewed monocularly, on a simultaneous form-comparison task; roughly equal effects of en...

The performance of wireless communication systems is predominantly dependent on propagation environment and respective radiating antennas. Due to the shorter wavelength at Millimeter Wave (MmW) frequencies, the propagation loss through surroundings in indoor environments is typically very high. To improve the channel capacity and to reduce inter-user interference, a high gain directional antenn...

Successful obstacle avoidance requires a close coordination of the visual and the motor systems. Visual information is essential for adjusting movements in order to avoid unwanted collisions. Yet, established obstacle avoidance paradigms have typically either focused on gaze strategies or on motor adjustments. Here we were interested in whether humans show similar visuomotor sensitivity to obst...

A shifted field of view, an altered perception of optic flow speed, and gait asymmetries may influence heading direction in Parkinson's disease (PD). PD participants (left body-side onset, LPD, n=14; right body-side onset, RPD, n=9) and Healthy Control participants (n=17) walked a virtual hallway in which the optic flow speeds of the walls varied. Three-dimensional kinematics showed participant...