David A Hopkins

US Patent:

7370524, May 13, 2008

Filed:

Aug 15, 2005

Appl. No.:

11/205551

Inventors:

David James Hopkins - Livermore CA, US

Assignee:

Lawrence Livermore National Security, LLC - Livermore CA

International Classification:

G01M 1/16

US Classification:

731462, 73462

Abstract:

A control system and method for actively reducing vibration in a spindle housing caused by unbalance forces on a rotating spindle, by measuring the force-induced spindle-housing motion, determining control signals based on synchronous demodulation, and provide compensation for the measured displacement to cancel or otherwise reduce or attenuate the vibration. In particular, the synchronous demodulation technique is performed to recover a measured spindle housing displacement signal related only to the rotation of a machine tool spindle, and consequently rejects measured displacement not related to spindle motion or synchronous to a cycle of revolution. Furthermore, the controller actuates at least one voice-coil (VC) motor, to cancel the original force-induced motion, and adapts the magnitude of voice coil signal until this measured displacement signal is brought to a null. In order to adjust the signal to a null, it must have the correct phase relative to the spindle angle. The feedback phase signal is used to adjust a common (to both outputs) commutation offset register (offset relative to spindle encoder angle) to force the feedback phase signal output to a null.

US Patent:

45401730, Sep 10, 1985

Filed:

Dec 12, 1983

Appl. No.:

6/560372

Inventors:

David E. Hopkins - Livermore CA

International Classification:

A63B 2102

US Classification:

272139

Abstract:

A portable elastic exercising device which may be worn by the user to tone or firm up the wrist, arm and shoulder muscles while exercising not only in the conventional positions of standing, sitting, or lying, but more specifically, since the device is completely independent of the need to be anchored to a fixed object, it thereby permits the user to exercise while walking, running, or jogging, and has a single length of elastic cord that is twice passed through a flexible sheath to encompass the user's waist and whose two ends are also enclosed inflexible sheaths to form handles. Handle loops are maintained by covered steel wire ties or other fasteners.

US Patent:

53681126, Nov 29, 1994

Filed:

Jul 30, 1993

Appl. No.:

8/100623

Inventors:

Matthew J. Mount - Long Beach CA
David G. Hopkins - Riverside CA

Assignee:

Union Oil Company of California - Los Angeles CA

International Classification:

E21B 1500

US Classification:

175122

Abstract:

A measured and controlled tension is applied to one or more lines or cables attached to a drilling rig. Preferably, the tensioned line provide reactive torque support for the power swivel, The controlled tension allows a greater power swivel torque to be used on existing drilling rig structures and better distributes any portion of the torque load reacted by the structure. The controlled tension system can also be integrated into a fail-safe control system, where sensed cable failure or excessive cable loads cause a safe shutdown of operations, or the measured tension may also be based to control other drilling operations, such as hoisting speeds.

US Patent:

20220374468, Nov 24, 2022

Filed:

Mar 31, 2022

Appl. No.:

17/710434

Inventors:

- Santa Monica CA, US
Ryan Rifkin - Los Angeles CA, US
David Hopkins - Santa Monica CA, US
Jonathan Angelo - Los Angeles CA, US
Marcus Buffet - Los Angeles CA, US

International Classification:

G06F 16/583
G06F 16/587
H04N 5/232
G06Q 10/06

Abstract:

There is disclosed a system, apparatus and methods for optimizing photo selection. When a photographer takes photos as requested in a shot list, the photos are automatically assigned a quality score which correlates to how prominently the photo would be displayed in an online search. The photos and the quality scores are displayed to the photographer so that when the photographer has shot a sufficiently high quality photo then the photographer can stop shooting. Photos with the highest quality scores are optimal. The shot lists include reference photos, and if a new photo has a higher quality score than the corresponding reference photo, the new photo becomes the reference photo.

US Patent:

20200218774, Jul 9, 2020

Filed:

Mar 23, 2020

Appl. No.:

16/827632

Inventors:

- Fremont CA, US
Andrew Fong - Pleasanton CA, US
David Hopkins - Newark CA, US

International Classification:

G06F 17/11
G06F 30/36
G06F 30/367

Abstract:

Systems and methods for tuning an impedance matching network in a step-wise fashion are described. By tuning the impedance matching network in a step-wise fashion instead of directly to achieve optimum values of a radio frequency (RF) and a combined variable capacitance, processing of a wafer using the tuned optimal values becomes feasible.

US Patent:

20200067545, Feb 27, 2020

Filed:

Oct 31, 2019

Appl. No.:

16/669844

Inventors:

- Fremont CA, US
Andrew Fong - Pleasanton CA, US
David Hopkins - Newark CA, US

International Classification:

H04B 1/04
G06F 17/50
G05B 17/02

Abstract:

Systems and methods for reducing reflected towards a higher frequency radio frequency (RF) generator during a period of a lower frequency RF generator and for using a relationship to reduce reflected power are described. By tuning the higher frequency RF generator during the period of the lower frequency RF generator, precise control of the higher frequency RF generator is achieved for reducing power reflected towards the higher frequency RF generator. Moreover, by using the relationship to reduce the reflected power, time is saved during processing of a wafer.

US Patent:

20190272306, Sep 5, 2019

Filed:

May 9, 2019

Appl. No.:

16/408127

Inventors:

- Fremont CA, US
Andrew Fong - Pleasanton CA, US
David Hopkins - Newark CA, US

International Classification:

G06F 17/11
G06F 17/50

Abstract:

Systems and methods for tuning an impedance matching network in a step-wise fashion are described. By tuning the impedance matching network in a step-wise fashion instead of directly to achieve optimum values of a radio frequency (RF) and a combined variable capacitance, processing of a wafer using the tuned optimal values becomes feasible.

US Patent:

20190253833, Aug 15, 2019

Filed:

Apr 23, 2019

Appl. No.:

16/391696

Inventors:

- Santa Monica CA, US
Evan RIFKIN - Pacific Palisades CA, US
Steve Lackenby - Topanga CA, US
Alex Pronin - Calabasas CA, US
David Hopkins - Santa Monica CA, US

International Classification:

H04W 4/021
H04W 4/21
H04L 29/08

Abstract:

There is disclosed herein a non-volatile machine-readable medium storing a program, a system and method for enabling proximity-based, peer-to-peer sharing of media in which a first device having a wireless communication surrounding the device detects other wireless devices within the region. Communication connections are formed between the wireless devices and a list of the authenticated connections is maintained. Without input from a user, media is shared between the individual devices on the authenticated connections list and a remote server, subject to permissions pre-set by the individual devices. Devices not included in the list of authenticated connections are blocked from accessing the media. Access to the media is available for a period of time, after which time access to the media is blocked for all devices.