Patents by Inventor Kevin Townsend

Kevin Townsend has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20190265268
    Abstract: A method of manufacturing an inertial measurement unit (IMU) comprises fabricating a plurality of individual MEMS inertial sensor packages at a package level as sealed packages containing a MEMS inertial sensor chip and an integrated circuit electrically connected together. Fabricating the individual MEMS inertial sensor packages comprises forming mechanical interconnect features in each package and assembling the IMU by mechanically interconnecting each individual MEMS inertial sensor package with another individual MEMS inertial sensor package in a mutually orthogonal orientation.
    Type: Application
    Filed: January 30, 2019
    Publication date: August 29, 2019
    Inventors: Kevin Townsend, Michael Terence Durston
  • Publication number: 20190242708
    Abstract: A vibrating structure angular rate sensor is provided which comprises a substrate; a plurality of flexible supporting structures fixed to the substrate; an annular member which is flexibly supported by the plurality of supporting structures to move elastically relative to the substrate; and an electrical drive system configured to drive the annular member to oscillate in a primary mode of oscillation with a resonant frequency f1. The plurality of supporting structures comprises at least one active supporting structure which carries an active electrical connection from the annular member to the drive system; and at least one passive supporting structure which does not carry an active electrical connection from the annular member to the drive system.
    Type: Application
    Filed: January 30, 2019
    Publication date: August 8, 2019
    Inventor: Kevin Townsend
  • Publication number: 20190245318
    Abstract: The present disclosure relates to a ring-type laser system supporting circumferential radial emission. A cylindrical ring waveguide provides optical confinement in the radial and axial dimensions supporting a plurality of traveling wave modes with various degrees of confinement. The waveguide contains a gain media which is gain tailored to offset modal confinement factors of the modal constituency to favor radial emission. The selected modes radiate energy as they circulate the laser resonator with a 360 degree output coupler. The design is applicable toward both micro-resonators and resonators much larger than the optical wavelength, enabling high output powers and scalability. The circumferential radial laser emission can be concentrated by positioning the cylindrical ring laser inside a three-dimensional conical mirror thereby forming a laser ring of light propagating in the axial dimension away from the surface of the laser, which can be subsequently collimated for focused using conventional optics.
    Type: Application
    Filed: January 21, 2019
    Publication date: August 8, 2019
    Inventors: Ronald LaComb, Kevin LaComb, Sallie Townsend
  • Publication number: 20190145771
    Abstract: A vibrating structure gyroscope includes an annular resonator arranged to vibrate in a plane in response to electrostatic driving forces and a set of capacitive drive electrodes arranged to apply a voltage creating an electrostatic driving force to excite a primary cos n? resonance along a primary axis at a primary frequency fP, such that Coriolis forces, resulting from an angular rate applied about an out-of-plane axis, induce a secondary cos n? resonance along a secondary axis at a secondary frequency fS. The gyroscope also includes digitally-controlled first and second sets to creating a static electrostatic balancing.
    Type: Application
    Filed: September 27, 2018
    Publication date: May 16, 2019
    Inventors: Kevin Townsend, Andrew Kazer
  • Patent number: 10161957
    Abstract: A method for closed loop operation of a capacitive accelerometer comprising: a proof mass; first and second sets of both fixed and moveable capacitive electrode fingers, interdigitated with each other; the method comprising: applying PWM drive signals to the fixed fingers; sensing displacement of the proof mass and changing the mark:space ratio of the PWM drive signals, to provide a restoring force on the proof mass that balances the inertial force of the applied acceleration and maintains the proof mass at a null position; detecting when the mark:space ratio for the null position is beyond a predetermined upper or lower threshold; and further modulating the PWM drive signals by extending or reducing x pulses in every y cycles, where x>1 and y>1, to provide an average mark:space ratio beyond the upper or lower threshold without further increasing or decreasing the mark length of the other pulses.
    Type: Grant
    Filed: March 17, 2015
    Date of Patent: December 25, 2018
    Assignee: ATLANTIC INERTIAL SYSTEMS, LIMITED
    Inventors: Kevin Townsend, Michael Terence Durston
  • Patent number: 10135454
    Abstract: A successive approximation Analog to Digital Converter (ADC), comprising: a sample and hold device arranged to sample and hold an input signal at the beginning of a conversion cycle; a successive approximation register that sequentially builds up a digital output from its most significant bit to its least significant bit; a digital to analog converter that outputs a signal based on the output of the successive approximation register; a comparator that compares the output of the digital to analog converter with an output of the sample and hold device and supplies its output to the successive approximation register; and a residual signal storage device arranged to store the residual signal at the end of a conversion cycle; and wherein the successive approximation ADC is arranged to add the stored residual signal from the residual signal storage device to the input signal stored on the sample and hold device at the start of each conversion cycle.
    Type: Grant
    Filed: December 3, 2015
    Date of Patent: November 20, 2018
    Assignee: ATLANTIC INERTIAL SYSTEMS LIMITED
    Inventors: Michael Terence Durston, Kevin Townsend, Douglas Robert Sitch
  • Publication number: 20180111826
    Abstract: An micro electro mechanical sensor comprising: a substrate; and a sensor element movably mounted to a first side of said substrate; wherein a second side of said substrate has a pattern formed in relief thereon. The pattern formed in relief on the second side of the substrate provides a reduced surface area for contact with the die bond layer. The reduced surface area reduces the amount of stress that is transmitted from the die bond layer to the substrate (and hence reduces the amount of transmitted stress reaching the MEMS sensor element). Because the substrate relief pattern provides a certain amount of stress decoupling, the die bond layer does not need to decouple the stress to the same extent as in previous designs. Therefore a thinner die bond layer can be used, which in turn allows the whole package to be slightly thinner.
    Type: Application
    Filed: October 13, 2017
    Publication date: April 26, 2018
    Inventors: Michael DURSTON, Kevin TOWNSEND
  • Publication number: 20180017388
    Abstract: There is provided a method of sensing a rotation rate using a vibrating structure gyroscope, said gyroscope comprising an electronic control system comprising one or more control loops, wherein at least one of said control loops comprises a filter having a variable time constant, said method comprising the steps of: determining or estimating a characteristic of the vibrating structure of said gyroscope; and adapting or varying said time constant of said filter with the determined or estimated characteristic of said vibrating structure.
    Type: Application
    Filed: January 26, 2016
    Publication date: January 18, 2018
    Inventors: Kevin TOWNSEND, Andrew CLIFFORD, Nicholas WILKINSON
  • Publication number: 20170346497
    Abstract: A successive approximation Analogue to Digital Converter (ADC), comprising: a sample and hold device arranged to sample and hold an input signal at the beginning of a conversion cycle; a successive approximation register that sequentially builds up a digital output from its most significant bit to its least significant bit; a digital to analogue converter that outputs a signal based on the output of the successive approximation register; a comparator that compares the output of the digital to analogue converter with an output of the sample and hold device and supplies its output to the successive approximation register; and a residual signal storage device arranged to store the residual signal at the end of a conversion cycle; and wherein the successive approximation ADC is arranged to add the stored residual signal from the residual signal storage device to the input signal stored on the sample and hold device at the start of each conversion cycle.
    Type: Application
    Filed: December 3, 2015
    Publication date: November 30, 2017
    Applicant: Atlantic Inertial Systems Limited
    Inventors: Michael Terence Durston, Kevin Townsend, Douglas Robert Sitch
  • Publication number: 20170322029
    Abstract: A digitally controlled voltage controlled oscillator comprising an Nbit digital to analogue convertor arranged to receive a frequency change demand signal as a digital Nbit word, and having an output provided via an integrator to a voltage controlled oscillator configured to provide a frequency output.
    Type: Application
    Filed: October 27, 2015
    Publication date: November 9, 2017
    Inventors: Kevin Townsend, Michael Durston
  • Publication number: 20170153267
    Abstract: A method for closed loop operation of a capacitive accelerometer uses a single current source (62) and a single current sink (64) to apply an in-phase drive signal V1? to a first set of fixed capacitive electrode fingers and a corresponding anti-phase drive signal V2? to a second set of fixed capacitive electrode fingers. This provides a net electrostatic restoring force on the proof mass for balancing the inertial force of the applied acceleration and maintains the proof mass at a null position.
    Type: Application
    Filed: June 26, 2015
    Publication date: June 1, 2017
    Applicant: Atlantic Inertial Systems Limited
    Inventors: Kevin Townsend, Michael Durston, Douglas Sitch
  • Publication number: 20170146562
    Abstract: In a method for open loop operation of a capacitive accelerometer, a first mode of operation comprises electrically measuring a deflection of a proof mass (204) from the null position under an applied acceleration using a pickoff amplifier (206) set to a reference voltage Vcm. A second mode of operation comprises applying electrostatic forces in order to cause the proof mass (204) to deflect from the null position, and electrically measuring the forced deflection so caused. In the second mode of operation the pickoff amplifier (206) has its input (211) switched from Vcm to Vss, using a reference control circuit (209), so that drive amplifiers (210) can apply different voltages Vdd to the proof mass (204) and associated fixed electrodes (202).
    Type: Application
    Filed: June 5, 2015
    Publication date: May 25, 2017
    Inventors: Michael Durston, Kevin Townsend
  • Publication number: 20170089947
    Abstract: A method for closed loop operation of a capacitive accelerometer comprising: a proof mass; first and second sets of both fixed and moveable capacitive electrode fingers, interdigitated with each other; the method comprising: applying PWM drive signals to the fixed fingers; sensing displacement of the proof mass and changing the mark:space ratio of the PWM drive signals, to provide a restoring force on the proof mass that balances the inertial force of the applied acceleration and maintains the proof mass at a null position; detecting when the mark:space ratio for the null position is beyond a predetermined upper or lower threshold; and further modulating the PWM drive signals by extending or reducing x pulses in every y cycles, where x>1 and y>1, to provide an average mark:space ratio beyond the upper or lower threshold without further increasing or decreasing the mark length of the other pulses.
    Type: Application
    Filed: March 17, 2015
    Publication date: March 30, 2017
    Applicant: Atlantic Inertial Systems Limited
    Inventors: Kevin Townsend, Michael Terence Durston
  • Patent number: 9374069
    Abstract: A method of processing an amplitude-modulated analog signal at a carrier frequency Fc comprises: digitizing the analog signal to produce an input bit stream that represents the amplitude of the analog signal; generating an in-phase reference bit stream that is synchronous to the carrier frequency Fc and represents an in-phase digital reference signal substantially in the form of a sine and/or cosine wave; and multiplying the input bit stream with the in-phase reference bit stream to produce an output bit stream representing the amplitude modulation of the analog signal.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: June 21, 2016
    Assignee: Atlantic Inertial Systems Limited
    Inventor: Kevin Townsend
  • Patent number: 9341476
    Abstract: An inertial sensor is described that has means for improving quadrature rejection The sensor is of a ring type, driven by a driver circuit, the sensor further comprising primary and secondary portions having corresponding signal pickoffs. The primary pickoff signal amplitude is controlled via an automatic gain control, the primary phase lock loop and VCO locks to the resonant frequency to provide the clocks for the synchronous detectors, the primary pickoff signals via the primary phase shift circuit is provided to the primary driver, the secondary pickoff signal being input into a detector circuit capable of detecting motion in the sensor. The secondary channel comprises a series of circuits that when operable in series significantly improve the quadrature rejection ability of the sensor. The circuits include a synchronous detector, passive and active filters and a decimator.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: May 17, 2016
    Assignee: SILICON SENSING SYSTEMS LIMITED
    Inventors: Kevin Townsend, Michael Durston
  • Publication number: 20160028380
    Abstract: A method of processing an amplitude-modulated analogue signal at a carrier frequency Fc comprises: digitising the analogue signal to produce an input bit stream that represents the amplitude of the analogue signal; generating an in-phase reference bit stream that is synchronous to the carrier frequency Fc and represents an in-phase digital reference signal substantially in the form of a sine and/or cosine wave; and multiplying the input bit stream with the in-phase reference bit stream to produce an output bit stream representing the amplitude modulation of the analogue signal.
    Type: Application
    Filed: July 25, 2014
    Publication date: January 28, 2016
    Inventor: Kevin Townsend
  • Patent number: 9234907
    Abstract: An angular velocity sensor is described with improved ageing and hysteresis properties. The sensor may be of a ring type driven by a driver circuit, the sensor further comprising primary and secondary portions having corresponding signal pickoffs. The gain of the primary pickoff signal and the capacitance of the primary portions of the sensor are controlled relative to the gain of the secondary pickoff and the capacitance of the secondary portions of the sensor. Control electronics is provided that enables matching of the relative signals from the respective channels. In this way, temperature hysteresis and ageing effects of materials used in forming the sensor are overcome.
    Type: Grant
    Filed: May 19, 2011
    Date of Patent: January 12, 2016
    Assignee: SILICON SENSING SYSTEMS LIMITED
    Inventors: Michael Durston, Kevin Townsend, Christopher Paul Fell
  • Patent number: 9176158
    Abstract: An inertial sensor is described that has a commanded test function. The sensor is of a ring type driven by a driver circuit, the sensor further includes primary and secondary portions having corresponding signal pickoffs. The primary pickoff signal amplitude is controlled via an automatic gain control, the primary phase lock loop and VCO locks to the resonant frequency to provide the clocks for the synchronous detectors, the primary pickoff signals via the primary phase shift circuit is provided to the primary driver, the secondary pickoff signal being input into a detector circuit capable of detecting motion in the sensor. The commanded test function includes a signal derived from the primary portion of the circuit and input into the two inputs of a differential amplifier in the secondary pickoff detector circuit.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: November 3, 2015
    Assignee: SILICON SENSING SYSTEMS LIMITED
    Inventors: Kevin Townsend, Michael Durston, Douglas Robert Sitch
  • Patent number: 9162875
    Abstract: An inertial sensor is described in which a resonant element is driven by control electronics into resonance. The control electronics includes an oscillator. A circuit is provided for matching the frequency of the oscillator with the frequency of the output of the resonant element such that the time to operation from start up of the sensor is minimized and the requirement of frequency matching a given sensor to the control electronics is removed.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: October 20, 2015
    Assignee: SILICON SENSING SYSTEMS LIMITED
    Inventors: Michael Durston, David Beasley, Kevin Townsend
  • Publication number: 20130233074
    Abstract: An angular velocity sensor is described with improved ageing and hysteresis properties. The sensor may be of a ring type driven by a driver circuit, the sensor further comprising primary and secondary portions having corresponding signal pickoffs. The gain of the primary pickoff signal and the capacitance of the primary portions of the sensor are controlled relative to the gain of the secondary pickoff and the capacitance of the secondary portions of the sensor. Control electronics is provided that enables matching of the relative signals from the respective channels. In this way, temperature hysteresis and ageing effects of materials used in forming the sensor are overcome.
    Type: Application
    Filed: May 19, 2011
    Publication date: September 12, 2013
    Applicant: SILICON SENSING SYSTEMS LIMITED
    Inventors: Michael Durston, Kevin Townsend, Christopher Paul Fell