Learn More
A miniaturized, telemetric, photoplethysmograph (PPG) sensor for long-term, continuous monitoring is presented in this paper. The sensor, called a "ring sensor," is attached to a finger base for monitoring beat-to-beat pulsation, and the data is sent to a host computer via a radio-frequency transmitter. Two major design issues are addressed: one is to(More)
Buckling is a highly nonlinear and singular phenomenon in thin beams, and is usually an undesired characteristic that must be prevented from occurring in engineered systems. Buckling, however, can be a useful mechanism for gaining extremely large displacement amplification, since a tiny displacement in the axial direction of the beam may lead to a large(More)
—A new type of touch sensor for detecting contact pressure at human fingertips is presented. Unlike traditional electronic gloves, in which sensor pads are placed between the fingers and the environment surface, this new sensor allows the fingers to directly contact the environment without obstructing the human's natural haptic senses. The finger touch(More)
Human hands employ characteristic patterns of actuation, or synergies, that contain much of the information required to describe an entire hand shape. In some cases, 80% or more of the total information can be described with only two scalar component values. Robotic hands, however, commonly only couple intra-finger joints, and rarely take advantage of this(More)
A new approach to the design and control of shape memory alloy (SMA) actuators is presented. SMA wires are divided into many segments and their thermal states are controlled individually in a binary manner. The Peltier effect is used for heating and cooling individual segments of the SMA. Unlike the traditional way of controlling the wire length by driving(More)
Densely arrayed skeletal myotubes are activated individually and as a group using precise optical stimulation with high spatiotemporal resolution. Skeletal muscle myoblasts are genetically encoded to express a light-activated cation channel, Channelrhodopsin-2, which allows for spatiotemporal coordination of a multitude of skeletal myotubes that contract in(More)