Ramsés V. Martínez

Harvard University | Harvard · Department of Chemistry and Chemical Biology

Systems and methods for providing flexible robotic actuators are disclosed. Some embodiments of the disclosed subject matter include a soft robot capable of providing a radial deflection motions; a soft tentacle actuator capable of providing a variety of motions and providing transportation means for various types of materials; and a hybrid robotic...

A soft robotic device includes a flexible body having a width, a length and a thickness, wherein the thickness is at least 1 mm, the flexible body having at least one channel disposed within the flexible body, the channel defined by upper, lower and side walls, wherein at least one wall is strain limiting; and a pressurizing inlet in fluid communic...

This paper demonstrates a new soft structure that uses a meso- or macro-scale elastic instability to generate a shape-memory effect similar to that exhibited by a ferroelastic material. It demonstrates the phase transitions, state switching, and shape-memory effects in this system, both in experiment and in simulation. The new class of materials de...

We report a low-cost, high-throughput benchtop method that enables thin layers of metal to be shaped with nanoscale precision by generating ultrahigh-strain-rate deformations. Laser shock imprinting can create three-dimensional crystalline metallic structures as small as 10 nanometers with ultrasmooth surfaces at ambient conditions. This technique...

Spectrally encoded confocal microscopy (SECM) is a reflectance confocal microscopy technology that can rapidly image large areas of luminal organs at microscopic resolution. One of the main challenges for large-area SECM imaging in vivo is maintaining the same imaging depth within the tissue when patient motion and tissue surface irregularity are p...

This article describes the use of embossing and "cut-and-stack" methods of assembly, to generate microfluidic devices from omniphobic paper and demonstrates that fluid flowing through these devices behaves similarly to fluid in an open-channel microfluidic device. The porosity of the paper to gases allows processes not possible in devices made usin...

This paper describes the modular magnetic assembly of reconfigurable, pneumatically actuated robots composed of soft and hard components and materials. The soft components of these hybrid robots are actuators fabricated from silicone elastomers using soft lithography, and the hard components are acrylonitrile–butadiene–styrene (ABS) structures made...

This paper describes the fabrication of functional optical devices by sectioning quantum-dot-in-nanowires systems with predefined lengths and orientations. This fabrication process requires only two steps: embedding the nanowires in epoxy, and using an ultramicrotome to section them across their axis ("nanoskiving"). This work demonstrates the comb...

The fabrication and properties of “fluoroalkylated paper” (“RF paper”) by vapor-phase silanization of paper with fluoroalkyl trichlorosilanes is reported. RF paper is both hydrophobic and oleophobic: it repels water (θappH2O>140°), organic liquids with surface tensions as low as 28 mN m-1, aqueous solutions containing ionic and non-ionic surfactant...

This paper characterizes the ability of soft pneumatic actuators and robots to resist mechanical insults that would irreversibly damage or destroy hard robotic systems—systems fabricated in metals and structural polymers, and actuated mechanically—of comparable sizes. The pneumatic networks that actuate these soft machines are formed by bonding two...

In this work we form and manipulate nanometer-size liquid bridges of nonpolar organic solvents such as octane and 1-octene with a dynamic force microscope. These menisci have been used to confine chemical reactions that gave rise to the fabrication of nanometer-size structures. Peer reviewed

This paper describes the fabrication of pressure-driven, open-channel microfluidic systems with lateral dimensions of 45-300 microns carved in omniphobic paper using a craft-cutting tool. Vapor phase silanization with a fluorinated alkyltrichlorosilane renders paper omniphobic, but preserves its high gas permeability and mechanical properties. When...

Spectrally-encoded endoscopy (SEE) is an ultraminiature endoscopy technology that acquires high-definition images of internal organs through a sub-mm endoscopic probe. In SEE, a grating at the tip of the imaging optics diffracts the broadband light into multiple beams, where each beam with a distinctive wavelength is illuminated on a unique transve...

Soft robotic tentacles that move in three dimensions upon pressurization are fabricated by composing flexible elastomers with different tensile strengths using soft lithographic molding. These actuators are able to grip complex shapes and manipulate delicate objects. Embedding functional components into these actuators (for example, a needle for de...

The front cover image illustrates a soft robotic tentacle with a textured surface fabricated by composing flexible elastomers using soft lithographic molding. These soft tentacles can manipulate delicate objects and house functional components that extend their capabilities (for example, a video camera). More details can be found in the article by...

This chapter reviews soft lithographic approaches to nanofabrication: that is, the generation and replication of patterns using a polymeric stamp bearing relief features. Soft lithographic methods are playing roles in science and technology where conventional methods of fabrication - for example, those developed for semiconductor manufacturing - ar...

This paper demonstrates the use of aqueous multiphase systems (MuPSs) as media for rate-zonal centrifugation to separate nanoparticles of different shapes and sizes. The properties of MuPSs do not change with time or during centrifugation; this stability facilitates sample collection after separation. A three-phase system demonstrates the separatio...

The development of soft pneumatic actuators based on composites consisting of elastomers with embedded sheet or fiber structures (e.g., paper or fabric) that are flexible but not extensible is described. On pneumatic inflation, these actuators move anisotropically, based on the motions accessible by their composite structures. They are inexpensive,...

A nanopatterning method to deposit ferritin proteins with nanoscale accuracy over large areas is reported. Selective deposition is driven by the electrostatic interactions existing between the proteins and nanoscale features. Upon deposition, the protein shell can be removed by heating the patterns in an oxygen atmosphere. This leaves exposed the i...

The invention is related to the field of photodetectors, and in particular to photodetectors having a hybrid plasmonic nanostructured arrangement.

Dieser Aufsatz handelt von “Nanoskiving” (zu Deutsch etwa: Nano-Hartschälen oder Nano-Dünnschleifen) – einer einfachen und kostengünstigen Methode zur Nanofertigung, die die Notwendigkeit eines Zugangs zu Reinräumen und den dazugehörigen Einrichtungen minimiert, und die es zudem ermöglicht, Nanostrukturen aus Materialien und in Formen zu erstellen,...

This Review discusses nanoskiving--a simple and inexpensive method of nanofabrication, which minimizes requirements for access to cleanrooms and associated facilities, and which makes it possible to fabricate nanostructures from materials, and of geometries, to which more familiar methods of nanofabrication are not applicable. Nanoskiving requires...

Convenient and inexpensive methods to pattern the facets of optical fibers with metallic nanostructures would enable many applications. This communication reports a method to generate and transfer arrays of metallic nanostructures to the cleaved facets of optical fibers. The process relies on nanoskiving, in which an ultramicrotome, equipped with a...

Quantum chemical calculations at the B3LYP/aug-cc-PVTZ level show that CO2 can spontaneously break in the presence of an electric field above 40 V/nm. The energetics of the reaction was further assessed by single-point CCSD(T) calculations, which show that the electric field transforms the reaction from endothermic to exothermic. The rupture occurs...

This paper examines the factors that influence the quality of nanostructures fabricated by sectioning thin films with an ultramicrotome ("nanoskiving"). It surveys different materials (metals, ceramics, semiconductors, and conjugated polymers), deposition techniques (evaporation, sputter deposition, electroless deposition, chemical-vapor deposition...

We report a top-down process for the fabrication of single-crystalline silicon nanowire circuits and devices. Local oxidation nanolithography is applied to define very narrow oxide masks on top of a silicon-on-insulator substrate. In a plasma etching, the nano-oxide mask generates a nanowire with a rectangular section. The nanowire width coincides...

We report a tip-based nanofabrication method to generate carbon nanopatterns. The process uses the field-induced transformation of carbon dioxide gas into a solid material. It requires the application of low-to-moderate voltages similar to 10-40 V. The method allow us to fabricated sub-25 nm dots and it can be up scaled to pattern square centimeter...

Ricardo Garcia, Eugenio Coronado, and co-workers demonstrate on p. 588 large-scale patterning of single ferritin molecules by sequential (atomic force microscopy local oxidation) and parallel approaches (lithographically controlled wetting). The nanopattern size matches the size of the protein (∼10 nm). Electrostatic interactions, capillary forces,...

Patterning of single ferritin molecules by sequential (atomic force microscopy local oxidation) and parallel approaches (lithographically controlled wetting). The nanopattern size matches the size of the protein (10 nm). Electrostatic interactions, capillary forces, surface functionalization, and nanolithography are used to achieve the desired prot...

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física de la Materia Condensada . Fecha de lectura: 21-07-09 Bibliogr.: p.202-206

The emergence of an ultrasensitive sensor technology based on silicon nanowires requires both the fabrication of nanoscale diameter wires and the integration with microelectronic processes. Here we demonstrate an atomic force microscopy lithography that enables the reproducible fabrication of complex single-crystalline silicon nanowire field-effect...

The miniaturization limits of electronic and mechanical devices depend on the minimum pattern periodicity that is stable in ambient conditions. Here we demonstrate an atomic force microscopy lithography that enables the patterning of 2 nm organic structures with 6 nm periodicities in air. We also demonstrate that the lithography can be up-scaled fo...

Nanometre-size menisci of various liquids such as water, ethanol, 2-propanol, octane, and 1-octene have been formed and used to confine chemical reactions by using an atomic force microscope. The application of a bias voltage between a conductive scanning probe tip separated a few nanometres from a sample surface enables the field-induced formation...

The development of nanometer-scale lithographies is the focus of an intense research activity because progress on nanotechnology depends on the capability to fabricate, position and interconnect nanometer-scale structures. The unique imaging and manipulation properties of atomic force microscopes have prompted the emergence of several scanning prob...

Nanometer-size menisci of organic liquids such as octane and 1-octene have been formed and used to confine chemical reactions. The application of a bias voltage between a conductive scanning probe tip separated a few nanometers from a silicon surface allows the field-induced formation of nanometer-size liquid menisci that can subsequently be used t...