Michael A Matthews

US Patent:

20020181739, Dec 5, 2002

Filed:

Jun 4, 2002

Appl. No.:

10/162426

Inventors:

Robert Hallowell - Nashua NH, US
Michael Matthews - Billerica MA, US
David Clark - Walpole MA, US

Assignee:

MASSACHUSETTS INSTITUTE OF TECHNOLOGY - CAMBRIDGE MA

International Classification:

G06K009/40

US Classification:

382/100000, 382/199000, 382/274000

Abstract:

A method and apparatus for identifying a weather condition from visible imagery. A sequential series of visible images depicting a field of view is received. A composite visible image representing a long-term average of the monitored field of view is maintained and updated with each subsequent image. Each received image and the composite visible image are edge-detection filtered. Persistent edges existing in both the received image and the composite visible image are extracted and used to predict a weather condition. In one embodiment, a statistical value determined from the extracted edge image is used to predict visibility using a predetermined scoring function.

US Patent:

20220187458, Jun 16, 2022

Filed:

Dec 13, 2021

Appl. No.:

17/549124

Inventors:

- Mountain View CA, US
Bryce Remesch - Hollis NH, US
Michael R. Matthews - Portola Valley CA, US
David Sobel - Los Altos CA, US
Imam Uz Zaman - San Jose CA, US

International Classification:

G01S 17/34
G01S 17/48
G01S 17/931
B60W 30/08

Abstract:

The subject matter of this specification can be implemented in, among other things, systems and methods of optical sensing that utilize time and frequency multiplexing of sensing signals. Described are, among other things, a light source subsystem to produce a first beam having a first frequency and a second beam having a second frequency, a modulator to impart a modulation to the second beam, and an optical interface subsystem to receive a third beam caused by interaction of the first beam with an object and a fourth beam caused by interaction of the second beam with the object. Also described are one or more circuits to determine, based on a first phase information carried by the third beam, a velocity of the object, and then determine, based on a second phase information carried by the third beam and the first phase information, a distance to the object.