The Charles Stark Draper Laboratory, Inc.

James Alan Bickford

Marc Steven Weinberg

Louis Kratchman

Paul A Ward

Jonathan Jay Bernstein

Amy Elizabeth Duwel

Daniel Kenneth Freeman

Stephanie Lynne Golmon

Ronald Steven McNabb, Jr

Daniel I Harjes

John R Williams

William David Sawyer

John Joseph LeBlanc

James S Pringle, Jr

John J Le Blanc

William A Lenk

Max Lindsay Turnquist

Eugene H Cook

Jesse J Wheeler

William Joseph Trinkle, Jr

Anthony Petrovich

Joseph M Kinast

Laura Jane Mariano

Richard D Elliott

James D Derouin

Mirela G Bancu

Richard David Elliott, Iii

Daniel F Traviglia

Michael Joseph Tomaino-Iannucci

Ronald Edmund Gagnon, Jr

Kasey Russell

Andrew Reiter

David G D'Amore

John Shattler Fullford

Thomas Francis Marinis, Jr

A control circuit for an electrostatic machine includes a current source or sink, an inductor, a switching network coupled between the current source or sink and the electrostatic machine, and between the inductor and the electrostatic machine. A controller is configured to automatically cause the switching network to connect the current source or sink to the electrostatic machine each half-cycle of a periodically alternating polarity. At each polarity alternation, the electrostatic machine is isolated from the current source or sink for a first period of time. At each polarity alternation, the inductor is connected to the electrostatic machine for a second period of time while the electrostatic machine is isolated from the current source or sink, and then disconnect the inductor from the electrostatic machine.

High-power electrostatic machines

According to various aspects, a sensor system is provided comprising a first substrate configured to be coupled to a user, an electric field detector to detect a user electric field and comprising a second substrate, a proof mass positioned above the second substrate, one or more electrodes coupled to the second substrate, and a control circuit coupled to the one or more electrodes, the control circuit being configured to determine a change in capacitance between the proof mass and each electrode responsive to torsional movement of the proof mass responsive to the electric field, and a controller coupled to the first substrate and being configured to receive, from the detector, information indicative of each change in capacitance between the proof mass and each electrode, and determine, based on the information, characteristics of the electric field in at least two dimensions.

Miniature electric field detector

An electrostatic motor includes a cylindrical rotor and a stator. Electrodes are disposed on an inside cylindrical surface of the stator. Electrets and/or electrically conductive electrodes are disposed on the cylindrical rotor and a dielectric fluid fills space between the rotor and the stator to prevent discharge of the electrets. A mask is used to charge portions of an electret cylinder or other curved surface.

Electrostatic motor

An electromagnetic gradiometer that includes multiple torsionally operated MEMS-based magnetic and/or electric field sensors with control electronics configured to provide magnetic and/or electric field gradient measurements. In one example a magnetic gradiometer includes a first torsionally operated MEMS magnetic sensor having a capacitive read-out configured to provide a first measurement of a received magnetic field, a second torsionally operated MEMS magnetic sensor coupled to the first torsionally operated MEMS magnetic sensor and having the capacitive read-out configured to provide a second measurement of the received magnetic field, and control electronics coupled to the first and second torsionally operated MEMS magnetic sensors and configured to determine a magnetic field gradient of the received magnetic field based the first and second measurements from the first and second torsionally operated MEMS electromagnetic sensors.

Electromagnetic gradiometers

Aspects are generally directed to a compact and low-noise electric field detector, methods of operation, and methods of production thereof. In one example, an electric field detector includes a proof mass, a source of concentrated charge coupled to the proof mass, and a substrate having a substrate offset space defined therein, the proof mass being suspended above the substrate offset space. The electric field detector further includes a sense electrode disposed on the substrate within the substrate offset space and proximate the proof mass, the sense electrode being configured to measure a change in capacitance relative to the proof mass from movement of the proof mass in response to a received electric field at the source of concentrated charge. The electric field detector includes a control circuit coupled to the sense electrode and configured to determine a characteristic of the electric field based on the measured change in capacitance.

Aspects and embodiments are generally directed to magnetic field detector systems and methods. In one example, a magnetic field detector system includes a proof-mass including a magnetic dipole source, a plurality of supports, each individual support of the plurality supports being coupled to the proof-mass, a plurality of sensors, each individual sensor of the plurality of sensors positioned to measure a resonant frequency of a corresponding support of the plurality of supports, and a controller coupled to each individual sensor of the plurality of sensors, the controller configured to measure a characteristic of a magnetic field imparted on the proof-mass based on at least a first resonant frequency of the measured resonant frequencies.

Magnetic field detector system

Aspects and embodiments are generally directed to electric field detector systems and methods. In one example, an electric field detector system includes a proof-mass including a source of concentrated charge, a plurality of supports, each individual support of the plurality supports being coupled to the proof-mass, a plurality of sensors, each individual sensor of the plurality of sensors positioned to measure a resonant frequency of a corresponding support of the plurality of supports, and a controller coupled to each individual sensor of the plurality of sensors, the controller configured to measure a characteristic of an electric field imparted on the proof-mass based on at least a first resonant frequency of the measured resonant frequencies.

Electric field detector system

Aspects are generally directed to systems and methods that integrate contactless electric field detectors to measure biophysical signals generated by a body. In one example, a biophysical sensing system includes a sensing assembly including an array of contactless electric field detectors, each of the contactless electric field detectors being configured to sense a corresponding component of an electric field generated by a body, a control system to receive sensor data indicative of the components of the electric field sensed by each of the contactless electric field detectors, the control system being configured to generate an estimate of the electric field based on the sensor data, and a feedback system coupled to at least the control system, the feedback system including at least one feedback interface, the feedback system being configured to operate the feedback interface to provide feedback based on the estimate of the electric field.

Biophysical sensing systems and methods using non-contact electric field detectors

Compact low-loss antennas and methods for long range two-way communication are provided. In one example, a mechanical antenna includes a first material having first embedded electric charge carriers, a second material having second embedded electric charge carriers, and an actuator coupled to at least one of the first material and the second material, the actuator being configured to generate a monopole current and transmit a low frequency signal by causing kinematic motion of the first material relative to the second material.

Mechanical antenna

An ultra-low noise sensor for magnetic fields comprises a mechanically resonant structure having a magnetized proof mass. The displacement of the proof mass due to a magnetic field provides a high resolution and highly amplified measurement of magnetic field fluctuations near the resonance frequency. A flux modulator may be used with the resonant structure to amplify magnetic fluctuations in a non-resonant frequency band. The resonant structure, combined with a high resolution readout device and a frequency-compensating numerical processor, can amplify magnetic fluctuations in a broad range of frequencies. A solenoid coil surrounding the resonant structure may be used to null the quasi-static earth's magnetic field and thereby increase the dynamic range of the sensor. Cryogenically cooling the resonant structure can improve the resolution of the sensor. A magnetometer that embodies features of the present invention is miniaturized and has improved amplification and resolution at room temperature.

Ultra-low noise sensor for magnetic fields

An electronic device includes a substrate and a plurality of sensors. Each sensor is disposed in a well over the substrate and includes a working electrode, an inner filling solution disposed thereover, and an ion-selective membrane. The working electrode is in contact with the substrate and the ion-selective membrane is disposed over the inner filling solution and substantially seals the well.

Three-dimensional metal ion sensor arrays on printed circuit boards

An in-line loss-on-ignition measurement system includes an on-site extractor subsystem configured to collect fuel or a combustion by-product from a hydrocarbon fuel burning plant. An on-site analyzer is configured to receive the collected matter from the extractor subsystem and configured to weigh the collected matter, burn the collected matter, and weight the collected matter again. A controller is responsive to the analyzer and is configured to determine the loss-on-ignition data for the plant based on the weight of the collected matter before and after it is burned in the analyzer.

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Winchester, MA, United States of America

James Alan Bickford