Turtle Beach Corporation

Ultrahaptics IP Ltd

Ultraleap Limited

Brian Alan Kappus

Elwood Grant Norris

Benjamin John Oliver Long

Mark W Norris

David S Hecht

Justin Rorke Buckland

Adam John Robert Jackson

Amaru Daniel Araya-Williams

Richard Kulavik

Thomas Andrew Carter

James A Barnes

Michele Iodice

Rafel Jibry

Robert Charles Blenkinsopp

Orestis Georgiou

Adam Jackson

Benjaimin John Oliver Long

Gavin Alistair David Cutting

William Wren

Adam Price

Salvador Catsis

Rob Malkin

Keith Chipperfield

Victor Joseph Manzella, Jr

Benjamin Long

Jonathan Martinez MUÑOZ

Adam Harwood

A method for specifying desired quantities of the energy flux of the combined waves of acoustic radiation pressure to apply producing a mid-air haptic pushing force, which has the effect of simultaneously reducing the harmonic distortion present is described. Further, a method for communicating only the summaries of acoustic field contributions at the required locations in the form of summed portions of the relatively small matrix whose row and column count depend only on the control point count is described. Further, phased arrays of ultrasonic speakers can produce a relatively large amount of acoustic energy which is usually directed in a specific direction or focused to a particular point depending on the application of the array. Further, to allow the system to be driven more strongly than usual, the complex-valued linear system that governs the drive signal to each control point is solved twice. Further, to achieve mid-air haptics with high precision the radiation pressure generated must be modelled accurately.

Features of airborne ultrasonic fields

An acoustic matching structure is used to increase the power radiated from a transducing element with a higher impedance into a surrounding acoustic medium with a lower acoustic impedance. The acoustic matching structure consists of a thin, substantially planar cavity bounded by a two end walls and a side wall. The end walls of the cavity are formed by a blocking plate wall and a transducing element wall separated by a short distance (less than one quarter of the wavelength of acoustic waves in the surrounding medium at the operating frequency). The end walls and side wall bound a cavity with diameter approximately equal to half of the wavelength of acoustic waves in the surrounding medium. In operation, a transducing element generates acoustic oscillations in the fluid in the cavity. The transducing element may be an actuator which generates motion of an end wall in a direction perpendicular to the plane of the cavity to excite acoustic oscillations in the fluid in the cavity, and the cavity geometry and resonant amplification increase the amplitude of the resulting pressure oscillation. The cavity side wall or end walls contain at least one aperture positioned away from the center of the cavity to allow pressure waves to propagate into the surrounding acoustic medium.

Blocking plate structure for improved acoustic transmission efficiency

Disclosed are methods to manipulate a given parametrized haptic curve in order to yield a smooth phase function for each acoustic transducer which minimizes unwanted parametric audio. Further, the impulse response of a haptic system describes the behavior of the system over time and can be convolved with a given input to simulate a response to that input. To produce a specific response, a deconvolution with the impulse response is necessary to generate an input.

Minimizing unwanted responses in haptic systems

A digital signal generation assumes that a base frequency (the frequency with which the primitive phase angles are specified relative to) is equal to the carrier frequency for all relevant times. But this causes errors in the digital signals output to each array element transducer. Thus, it is necessary for the development of a signal generation system that is capable of producing a digital signal using the free selection of amplitude and phase. This is used to produce a substantially error-free signal that preserves the amplitude and phase relative to a constant base frequency while allowing the carrier frequency to vary.

Reducing harmonic distortion by dithering

Described herein are techniques for tracking objects (including human body parts such as a hand), namely: 1) two-state transducer interpolation in acoustic phased-arrays; 2) modulation techniques in acoustic phased-arrays; 3) fast acoustic full matrix capture during haptic effects; 4) time-of-flight depth sensor fusion system; 5) phase modulated spherical wave-fronts in acoustic phased-arrays; 6) long wavelength phase modulation of acoustic field for location and tracking; and 7) camera calibration through ultrasonic range sensing.

Tracking in haptic systems

Defining critical spacing is necessary for steering of parametric audio. Comparing steering measurements both with and without a waveguide leads to a conclusion that the diffuse phyllotactic grating lobe contributes audio and is to blame for poor steering. In addition, the waveguide needs to function with correct phase offsets to achieve the steering required for performance. Arranging tubes so that the array configuration changes from rectilinear to another distribution is useful when the waveguide is short of critical spacing or constrained for space. Array designs may also capitalize on rectilinear transducer design while having the benefits of a transducer tiling that has irrational spacing to promote the spread of grating lobe energy.

Acoustic transducer structures

To resolve an issue related to the calibration of optical cameras in transducer-based mid-air haptic systems, the magnification of the motion induced on an optical camera by an acoustic field modulated at specific frequencies reveals very small temporal variations in video frames. This quantized distortion is used to compare different acoustic fields and to solve the calibration problem in an automatized manner. Further, mechanical resonators may be excited by ultrasound when it is modulated at the resonant frequency. When enough energy is transferred and when operating at the correct frequency, a user in contact with the device can feel vibration near areas of largest displacement. This effect can be exploited to create devices which can produce haptic feedback while not carrying a battery or exciter when in the presence of an ultrasonic source.

Haptic effects from focused acoustic fields

A phased array of ultrasonic transducers may create arbitrary fields that can be utilized to manipulate fluids. This includes the translation of drops on smooth surfaces as well speeding the evaporation of fluids on wetted hands. Proposed herein is the use airborne ultrasound focused to the surface of the hand. The risk is that coupling directly into the bulk of the hand may cause damage to the cellular material through heating, mechanical stress, or cavitation. Using a phased array, the focus may be moved around, thus preventing acoustic energy from lingering too long on one particular position of the hand. While some signaling may penetrate into the hand, most of the energy (99.9%) is reflected. Also disclosed are methods to couple just to the wetted surface of the hand.

Ultrasonic-assisted liquid manipulation

Estimating the field strength from an ultrasonic phased array can be done by summing the contribution of each transducer to the point of interest. Since this contribution is already calculated when creating a converging spherical wave, it can be reused to add a virtual microphone to the system. By monitoring this microphone and moving it along with new focus points, a robust system of field estimates and regulation may be established.

Dynamic capping with virtual microphones

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Poway, CA, United States of America

Brian Alan Kappus