Leland Stanford Junior University

Agilent Technologies, Inc.

Byron M Yu

Krishna V Shenoy

Teresa H Meng

William H McAllister

Gopal Santhanam

John Patrick Cunningham

Paul Nuyujukian

Caleb T Kemere

Vikash Gilja

Cynthia A Chestek

Stephen I Ryu

Artificial control of a prosthetic device is provided. A brain machine interface contains a mapping of neural signals and corresponding intention estimating kinematics (e.g. positions and velocities) of a limb trajectory. The prosthetic device is controlled by the brain machine interface. During the control of the prosthetic device, a modified brain machine interface is developed by modifying the vectors of the velocities defined in the brain machine interface. The modified brain machine interface includes a new mapping of the neural signals and the intention estimating kinematics that can now be used to control the prosthetic device using recorded neural brain signals from a user of the prosthetic device. In one example, the intention estimating kinematics of the original and modified brain machine interface includes a Kalman filter modeling velocities as intentions and positions as feedback.

Brain machine interface

A brain machine interface for decoding neural signals for control of a machine is provided. The brain machine interface estimates and then combines information from two classes of neural activity. A first estimator decodes movement plan information from neural signals representing plan activity. In one embodiment the first estimator includes an adaptive point-process filter or a maximum likelihood filter. A second estimator decodes peri-movement information from neural signals representing peri-movement activity. Each estimator is designed to estimate different aspects of movement such as movement goal variables or movement execution variables.

Decoding of neural signals for movement control

A contactless conductivity detector uses a signal electrode arranged longitudinally between two ground electrodes. Conveniently, the ground electrodes can be integral with a metal housing that electrically shields the detector electronics from external electrical noise. The ground electrodes are defined at the locations where a capillary separation channel extends through the housing. The signal electrode is coupled to an AC transmitter through a sense resistor; the signal electrode is also coupled to a receiver that provides an output corresponding to the magnitude of the AC signal developed at the signal electrode. The signal electrode is located at a voltage-divider node between the sense resistor and the resistances of the sample fluid between the signal electrode location and the ground electrode locations. Thus, the signal developed at the signal electrode reflects the sample fluid resistance, which is the inverse of its conductivity. This single-electrode configuration provides a relatively flat response to frequency so that a single-frequency can be used for detection, as opposed to a frequency sweep, which can be required for other contactless conductivity detectors. The result is a simpler and more cost effective contactless conductivity detector suitable for use with electrophoresis and other chemical-analysis systems.

Contactless conductivity detector with transmitter/receiver electrode

Growing community of inventors

San Jose, CA, United States of America

Byron M Yu