Abstract: A device for detecting contact pressure applied to a finger, the finger having a fingernail illuminated by light, comprises at least one photodetector for measuring a change in light reflected by an area of the finger beneath the fingernail in response to the contact pressure applied to the finger. The photodetector provides a signal corresponding to the change in light reflected. The device also includes a processor for receiving the signal and determining whether the change corresponds to a specified condition. The photodetector may be enclosed in a housing and coupled to the fingernail.

Abstract: A hybrid personal vehicle capable of holonomic omni-directional self-locomotion. The vehicle may be programmed to navigate to a specified location in a crowded household environment. Additionally, sensors are provided for accurate docking and tight mating with fixtures such as a toilet or bed. A controller determines a docking trajectory to a specified fixture and behaves with arbitrary stiffness in each degree of freedom about a determined center of compliance.

Abstract: A monitoring system for monitoring the health status of a patient and transmitting to a remote receiver a signal, based on measured physiological parameters. A sensor is incorporated in a finger ring or other article of apparel so as to monitor skin temperature, blood flow, blood constituent concentration, or pulse rate of the patient. The data are encoded for wireless transmission by mapping a numerical value associated with each datum to a pulse emitted after a delay of a specified duration following a fiducial time. Multiple ring bands and sensor elements may be employed for deriving three-dimensional dynamic characteristics of arteries and tissue of the finger.

Abstract: An apparatus for positioning a human subject on a surface and for transferring a subject from one surface to another. The subject is situated on the top surface of a fluid enclosure and an actuator mechanism causes local deformations of the top surface in such a manner as to create traveling waves whereby a force tangential to the top surface is exerted on the subject for moving the subject with respect to the surface. The actuator mechanism may be a motor driver and may be a plurality of linear actuators configured so as to cause local deformations of the top surface in a direction having a vertical and/or horizontal component. The linear actuators may be shape memory fibers.

Abstract: A reconfigurable mechanism for varying the footprint of a wheeled omnidirectional vehicle. The variable footprint mechanism consists of a pair of beams intersecting at a pivotal point in the middle. Two pairs of ball wheels at the diagonal positions of the vehicle chassis are mounted, respectively, on the two beams intersecting in the middle. The angle between the two beams varies actively so that the ratio of the wheel base to the tread may change. Independent servomotors driving the ball wheels allow the vehicle to move in an arbitrary direction from an arbitrary configuration as well as to change the angle between the two beams and thereby change the footprint. By controlling the beam angle, static stability may be augmented, the width of the vehicle may be reduced, and the effective transmission ratio relating the vehicle speed to individual actuator speeds may be varied in a continuous manner.