Massachusetts Institute of Technology

Other

Tissuevision, Inc.

Schlumberger Technology Corporation

The General Hospital Corporation

The Charles Stark Draper Laboratory, Inc.

Teradyne, Inc.

Brigham Young University

Sorurabh Kumar Saha

Martin L Culpepper

Shih-Chi Chen

Sourabh Kumar Saha

Robert Matthew Panas

Christopher M DiBiasio

Marcel Thomas

Alexander H Slocum, Jr

Larry L Howell

Spencer P Magleby

Julio C Guerrero

Sarosh M Patel

Kartik Mangudi Varadarajan

Zihao Zhang

Dariusz Golda

Rohit Girdhar

Magnetic transmissions and related methods are described. In one embodiment, an apparatus includes a magnetic screw comprising an elongate body, a nut selectively magnetically coupled to the magnetic screw, and a potential energy storage system and/or a resistive force component. The nut is configured to be displaced relative to the elongate body in a first direction in response to manipulation of a magnetic field between the magnetic screw and the nut when the nut is magnetically coupled to the magnetic screw. In embodiments including a potential energy storage system, the potential energy storage system may store potential energy when the nut is displaced in the first direction. In embodiments including a resistive force component, the resistive force component may resist motion of the nut in the first direction by applying a resistive force to the nut at least partially in an opposing second direction.

Magnetic transmission

A microtome method and apparatus includes a microtome blade configured to oscillate in a direction transverse to a direction of advancing a cut, and a first flexure to support and guide the blade. The first flexure is compliant in the transverse direction while being stiff in the cut direction. A second flexure operatively engaged at one end portion with the first flexure, is stiff in the transverse direction while being compliant in the cut direction. The other end portion of the second flexure is rotatably engaged by an eccentric driven by a rotatable actuator, which oscillates the blade in the transverse direction while effectively isolating non-transverse motion from the blade. The second flexure is configured to move independently of any guides or other stationary objects during oscillation.

Oscillating microtome with flexure drive

This invention relates to the low-cost manufacture of a tunable physical topographic pattern and more particularly to the manufacture of micro and nano scale hierarchical periodic wrinkle patterns that are generated upon compression of supported thin films. Disclosed herein is (i) a composite material with tunable hierarchical wrinkle patterns, wherein the composite material comprises a stretched and pre-patterned base layer and a thin film that is conformally attached to the pre-patterned surface of the base layer, (ii) a method of fabricating the pre-patterned base via pattern replication, and (iii) a method of fabricating tunable hierarchical wrinkle patterns, wherein the pattern can be deterministically switched across the hierarchical and non-hierarchical states via strain control.

Wrinkled surfaces with tunable hierarchy and methods for the preparation thereof

Wrinkling of supported thin films is a strain-driven phenomenon that enables scalable and low-cost fabrication of periodic micro and nano scale structures. The morphology of wrinkles depends on both the magnitude and the nature of compressive strains that are applied to the thin film. This disclosure presents the methods to fabricate asymmetric 2-D wrinkled structures using biaxial compressive strains. The method relies on the dependence of wrinkle morphology on both strains and strain paths to generate asymmetric 2D wrinkles. Asymmetry is achieved by deliberately traversing the system through a strain state that creates cracks along a preferential direction. Fabricated patterns include non-uniform zigzag wrinkles that demonstrate period doubling only along one direction.

Method to fabricate asymmetric wrinkles using biaxial strains

The pattern complexity and functional value of wrinkled structures can be substantially increased by fabricating the wrinkles on pre-patterned quasi-planar substrates instead of flat substrates. This disclosure presents the methods for fabricating pre-patterned polymeric surfaces that can be subsequently used as the substrates during manufacture of complex wrinkled structures. Pre-patterned substrates are generated by imprinting the pre-patterns onto the substrates during the curing process. Suitability for post-curing use in fabrication of wrinkles is ensured by (i) delayed imprinting that occurs close to but before the gelation point and (ii) gradual alignment of pre-patterns to the direction of stretch that is applied later during manufacture of wrinkled structures.

Method to fabricate pre-patterned surfaces during manufacture of complex wrinkled structures

Wrinkling of thin films is a strain-driven process that enables scalable and low-cost fabrication of periodic micro and nano scale patterns. However, real-world application is limited by the inability of current tools to provide the means for applying large, accurate, and non-equal biaxial strains via a device that can fit within the vacuum chambers that are required for thin film deposition/growth during wrinkling. The present biaxial tensile stage is a compact system that enables one to apply large and accurate non-equal biaxial strains to elastomeric films. It consists of (i) fixtures to clamp and hold films onto the stage, (ii) linear bearings for motion guidance, (iii) integrated actuators for real-time stretch control, (iv) base with kinematic coupling for registration to a metrology system, and (v) the structural frame.

Biaxial tensile stage for fabricating and tuning wrinkles

A gyroscope includes a first mass, a second mass, and a drive structure configured to drive each of the first mass and the second mass in a drive mode. The drive structure includes a first portion and a second portion, with the first portion being configured to drive the first mass in a direction along a drive axis and the second portion being configured to drive the second mass in a direction opposite to the first mass along the drive axis. The gyroscope further includes a sense structure configured to sense motion of each of the first mass and the second mass in a sense mode along a direction substantially perpendicular to the drive axis, and a plurality of flexures configured to couple the first portion to the second portion and further configured to decouple the drive mode and the sense mode.

Modal decoupling via flexure-based transmissions as applied to a micromachined tuning fork gyroscope

Passive stamp alignment system. The system includes a stamp supported by a stamp holder resting on three balls affixed to a top platform. A bottom platform supports a substrate to be aligned with the stamp. Means are provided for moving either the top or the bottom platform and holding the other platform stationary so as to contact the substrate with the stamp whereby the stamp holder is lifted away from each of the balls in sequence resulting in alignment of the stamp and the substrate parallel to each other.

System for passive alignment of surfaces

A compliant holder device for constraining an animal includes a device body, a nose cone, and compliant flexure arms having contact surfaces for constraining the animal's head. In use, an animal is placed on the device body, and the nose of the animal is placed in the nose cone to constrain the skull at the nose. The compliant flexure arms are flexed to increase the distance between the contact surfaces of respective compliant flexure arms, and the ears of the animal are placed between the contact surfaces of the flexed compliant flexure arms, wherein the flex in the compliant flexure provides pressure to and constrains the skull at the ears.

Compliant holder device for animal imaging and surgery

A nano-scale compliant mechanism includes a coupler and a plurality of nanotubes disposed for nano-scale motion relative to a grounded component. The nanotubes are fastened at one end to the coupler and at the other end to ground, to guide motion of the coupler relative to the ground. Particular embodiments include a plurality of parallel carbon nanotubes. An exemplary embodiment exhibits first and second regions of mechanical behavior; a first region governed by bulk elastic deformation of the nanotubes and a second region governed by compliant, hinge-like bending of the buckled nanotubes.

Carbon nanotube based compliant mechanism

A high-bandwidth MEMS actuation system includes actuator pairs coupled in parallel to a stage, each actuator energizable in a drive direction against a bias to an energized position, and movable upon deenergization, to the rest position to define an actuation cycle. The actuators are asymmetric, with an energization frequency greater than a bias frequency, and are opposably coupled to one another. A pulse generator alternately transmits pulses to the actuators, at an alternation frequency greater than the bias frequency. The pulse generator transmits the energization pulses to each of the actuator pairs sequentially at a sequence frequency greater than the cycle frequency. The actuators are each movable from energized to rest positions faster than the bias frequency, and the actuator pairs are sequentially energizable faster than the cycle frequency, wherein the stage is movable in one degree of freedom at a bandwidth of at least four times the cycle frequency.

Microfabricated mechanical frequency multiplier

An anchoring module capable of being secured within a structure includes at least one compliant ring configured to radially expand and an expandable device positioned within the compliant ring to expand the compliant ring from a relaxed state to interface with the structure. The anchoring module is part of a modular system used to harvest fluid, such as oil or natural gas from a structure, such as a pipe or well. Another module of the system, sometimes referred to as a support or back-up module, employs an expandable surface that is capable of expanding to the diameter of the interior of the borehole. These modules may be combined in a variety of configurations to support a sealing element, such as an inflatable sealing element. The self-conforming nature of the system obviates the need for prior knowledge of the structure or complex sensor systems to chart the structure. The anchoring module can also be utilized in a crawling system to convey tools inside a structure.

Anchoring system and method

A thermomechanical actuation system and method includes an elongated thermomechanical actuator (TMA), which is contoured so that electrical resistance at a mid-portion of the TMA is less than at end portions thereof. A pulse generator is electrically coupled to the TMA, and is configured to supply excitation pulses to the TMA. The excitation pulses are transient, so that each pulse is terminated prior to reaching a steady state amplitude, while having sufficient energy to heat the TMA to its predetermined operational temperature range.

Growing community of inventors

Marblehead, MA, United States of America

Martin L Culpepper