By Jim McMahon

(Legacy Article) Professor Jian-Young Wu has been conducting research on waves of neuronal activity in the neocortex of the brain. Wu and his colleagues at the Department of Physiology and Biophysics at Georgetown University Medical Center visualize wave-like patterns in the brain cortex using optical imaging and voltage-sensitive dyea method that depends on robust vibration isolation. Their neuronal specimens are derived from slices of rat neocortex, the outer layer of a mammal's brain, which is involved in higher functions such as sensory perception and generation of motor commands and, in humans, language.

The neurons of the neocortex are arranged in vertical structures called neocortical columns that measure about 0.5 mm in diameter and 2 mm in depth. Each column typically responds to a sensory stimulus representing a certain body part, or region of sound or vision.

In the human neocortex, it is postulated that there are about a half-million of these columns, each of which contains approximately 60,000 neurons.

The neocortex can be viewed as a huge web, consisting of billions to trillions of neurons and hundred of trillions of interconnections. While individual neurons are too simple to have intelligence, the collective behavior of the billions of interneuronal interactions occurring each second can be highly intelligent.

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Featured Product: BM-4 Bench Top Vibration Isolation Platform

• Can also be made cleanroom and vacuum capatible.
  
• Vertical natural frequency of 1/2 Hz or less can be achieved over the entire load range.
  
• Horizontal natural frequency is load dependent. 1/2 Hz or less can be achieved at or near the nominal load.
  
• See Performance for a typical transmissibility curve with 1/2 Hz natural frequency.
  

Pricing & sizes for BM-4

Specifications (pdf)

Negative-stiffness Minus K BM-8 vibration isolator beneath the Neubrescope.

By Jim McMahon

The latest generation of fiber optic sensing systems employed to monitor well conditions can augment operational performance in the oil & gas industry. Critical data about the downhole well environment from distributed fiber optic sensing (DFOS) systems improves engineers and scientists ability to arrive at decisions that support operational optimization. This leads to well production performance enhancement and safety at the well site, with the ultimate goal of optimizing production from oil and gas wells. There is no other current method to acquire the quality and level of detail about physical conditions in a wellbore compared to fiber optics.

Distributed acoustic sensing (DAS) is mainly used to listen to hydraulic fracturing related signals, fluid and gas flow signals, or to sense seismic source response, such as in a vertical seismic profile (VSP). DAS senses changes in small physical acoustic vibrations along a glass fiber optic strand encased in a cable to measure vibrations. There are thousands of detection points along the fiber in the subsurface fiber optic cable.

DFOS is a technology that enables continuous, real-time measurements along the entire length of a fiber optic cable at minimal spatial intervals. Unlike conventional sensor systems that rely on discrete sensors measuring at pre-determined points, distributed sensing does not rely upon manufactured, discrete sensors, but uses the optical fiber itself as both sensing device and two-way transmitter of the signal (light). Optical fiber is the sensing element. without any additional transducers in the optical path. Surface instruments called interrogator units (IU) send a series of laser light pulses into the fiber and records the return of the naturally occurring back-scattered light signal as a function of time. In doing this, the distributed sensing system measures at all points along the fiber which are at a pre-determined clock-time interval over periods of well operational time

Because fiber optic cable can be installed in harsh environments for long periods of time, the technology holds promise for environmental monitoring of sensitive geologic operations. Many geofluid systems require dynamic acoustic, temperature, strain and pressure monitoring at great pressure, depth and temperature. Sensors that employ fiber optic cables serve well for such deployments because they can withstand adverse environments. Downhole application includes oil and gas wells (hydraulic fracture completion operations, flow-back operations, long-term well monitoring, and well-integrity monitoring), geothermal wells, deep industrial waste disposal wells and other harsh environment applications.

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By Michael Fremer, Insider views on everything vinyl

Let's begin by discussing what SAT's XD1 Record Player System is not: It is not a Technics SP-10R in a sci-fiinspired plinthalthough the XD1's engine does begin life as the SP-10R's basic drive system, which is stripped down to a handful of essential components, reimagined, reengineered, and rebuilt to much higher mechanical standards..

Marc Gomez, SAT's designer, holds a master's degree in mechanical engineering and materials science. Before dedicating himself to creating the SAT tonearmby far the finest sounding and performing arm I've yet encountered (as unanimously corroborated by Stereophile readers who bought this very expensive product unheard as a result of my review)he was involved in a variety of projects for, among others, the European Space Agency and various European automobile manufacturers.

Even if it's not broken, why not fix it?
The XD1 is a compact disc player, though not a player of compact discs (footnote 1).

Its sculpted, satiny beauty goes beyond skin deep. The XD1's metalwork, and that of the SAT tonearms, is machined at a Swedish workshop that makes parts for Hasselblad cameras.

Gomez says that in designing the XD1, he focused on four main areas: isolation from external disturbances, speed stability, rigidity, and vacuum hold-down.

When Mr. Gomez began conceptualizing his design a decade ago, it was immediately clear to him, he says, that direct drive was the best way to spin a platter. His reasons were these: A direct-drive motor's rotational speed is just 33.3, 45, or 78rpm compared to several hundred rpm's required in the typical belt-drive design, and with direct drive the spindle is not laterally loaded as it is in belt-drive designs, so it receives only torque, not an off-center force. The amount of torque available means the 'table is less likely to drag during heavily modulated passages, something direct-drive advocates claim happens with most belt designs.

Gomez says the drive-unit is no an off-the-shelf motor designed for generic industrial applications. Rather, it is conceived and built from the ground up to drive the XD1 (except for those few elements he kept from the SP-10R motor, footnote 2). He says it's better balanced than the motors typically used on belt-drive and idler turntables.

These claims are hardly novel: If your old Technics SL-1200, which also uses a direct-drive motor, could talk, it would make the same claims. Nor did Gomez address the oft-cited disadvantages of direct-drive systems, which include motor "cogging" (torque ripple), noise, and "hunting and pecking" as the quartz-locked system readjusts to maintain speed consistency, a sort of analog "jitter" that belt-drive advocates claim is sonically more pernicious than the slow, gradual speed shifts a belt-drive table is more likely to experience.

Full article (with footnotes)...

Here is an image of 250 µm width of butterfly wing using University of California, Santa Barbara AFM with negative-stiffness vibration isolation.

(Lagacy 2013 article) With its development in 1986, and subsequent commercial introduction in 1989, the atomic force microscope (AFM) is one of the foremost tools for imaging and measuring materials and cells on the nanoscale. Revealing sample details at the atomic level, with resolution on the order of fractions of a nanometer, the AFM is instrumental for imaging an array of applications, such as defining surface characterizations, lithography, datastorage, and manipulation of atoms and nano-sized structures on a variety of surfaces.

The need for more precise vibration isolation with AFM, though, is becoming critical as resolutions continue to bridge from micro to nano. AFM systems are extremely susceptible to vibrations from the environment. When measuring a very few angstroms or nanometers of displacement, an absolutely stable surface must be established for the instrument. Any vibration coupled into the mechanical structure of the instrument will cause vertical and horizontal noise and bring about a reduction in the ability to measure with the highest resolution.

The vertical axis is the most sensitive for AFMs, but these microscopes are also quite sensitive to vibrations in the X and Y axes.

The atomic force microscope uses a sharp tip (probe), with a radius of curvature on the order of nanometers attached to the end of a tiny cantilever used to scan across a sample surface to image its topography and material properties. When the tip is brought into proximity of a sample surface, forces between the tip and the surface lead to a deflection of the cantilever This deflection is typically recorded using a laser beam that is reflected from the top surface of the cantilever to a photosensitive detector. The resultant position change of the cantilever allows characteristics such as mechanical, electrostatic, magnetic, chemical and other forces to be precisely measured by the AFM. These characteristics are displayed in a three-dimensional surface profile of the sample (in the X, Y and Z axes)an advantage that the AFM can provide compared to other microscopy techniques, such as the scanning electron microscope (SEM) which delivers a two-dimensional image of a sample (in the X and Y axes).

Minus K BM-1 Isolator.

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Abstract: Researchers in the Physics Department of St. Olaf College are using a uniquely designed, integrated nanoindenter-quartz microbalance apparatus to bridge the gap between the fundamental science of friction and the engineering of practical micromechanical systems. This level of micro-research requires extreme stability for the microbalance instrumentation. Since 2001, the lab has used negative-stiffness vibration isolation to achieve a high level of isolation in multiple directions, custom tailoring resonant frequencies to 0.5 Hz vertically and horizontally.

Introduction: Scientists do not fully understand what causes friction and wear between two surfaces at the molecular level. When designing a micromechanical system, the fundamental machine parts of gears, hinges, pistons, gimbals, and suspended beams that flex are included. Basic motions that are the essence of mechanics rely on these materials having durability and low or controllable friction. Mastering these forces that occur on small-scale surfaces of micromachines is a considerable challenge. When the mechanical parts are very small, their properties are dominated by minute surface forces that macroscopic machines are not sensitive enough to detect. This raises entirely new questions about how to maintain minute components and to keep them moving and protected from wear or breakage.

Silicon Uniformity:
Engineers have relied on extremely thin lubricant films to reduce friction and to keep parts moving inside tiny silicon-constructed microelectromechanical systems (MEMS). But these films have not been sufficiently effective in micromachines, which rely on relatively fast-moving parts that are in contact with each other, such as gears, gimbals, and pistons. Since the early 1980s, with the introduction of the first micromechanical machines, the vision has been to batch-fabricate these devices as silicon chips to link with circuitry that can be connected wirelessly. However, these small silicon machines often disintegrate after just a few hours of operation. This technology has, for some time, been struggling to make it to the marketplace. Decades of research in both academia and business has been undertaken to understand friction and wear well enough at these micro- and nano-scales to effectively lubricate and provide wear protection.

New Research Methodology:
Professor Brian Borovsky, Associate Professor in the Physics Department at St. Olaf College in Northfield, MN, has been researching micro/nanotribology for over two decades [14]. He has pioneered friction research as applied to very tiny micromechanical machines, having developed state-of-the-art instrumentation and a process that tests frictional properties of surfaces coated with ultrathin lubricants. His is one of the few labs that can measure friction of micromachine surfaces sliding past each other at very high speeds that approach 1m/s.

While equipped with scanning electron (SEM) and atomic force microscopy (AFM) for analysis of surfaces, the labs focus instrumentation is a specially designed force probe nanoindenter in conjunction with a quartz microbalance...

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The need for nano- precision has became increasingly important in many fields of research and manufacturing, inducing microelectromcs fabrication, laser/optical system applications and biological research. This has meant that so too has the need for vibration Isolation technology that better facilitates the operation of sensitive Instrumentation such as atomic force microscopes, scanning tunneling microscopes, laser interferometers and optical profilers.

Once the mainstay for stabilizing academia's and Industry's most critical microenginering instrumentation, pneumatic (gas or air pressurized) vibration Isolation tables are today proving unsatisfactory in isolating disruptive low-frequency vibrations. There is a growing trend for locating sensitive instrumentation in building to locations that are subject to extremely high levels of vibration and this is a significant stumbling block for pneumatic vibration isolation tables, meaning alternative vibration isolation solutions are required.

Vibration sources
Nano-level instrumentation is sensitive to extremely small payload vibrations that can be caused by a multitude of factors. Every structure (building) transmits vibrations from Internal and external sources In a building, heating and ventilation systems, fans, pumps and elevators are Just some of the mechanical devices that create vibrations. Outside a building, adjacent road traffic, nearby construction, aircraft and even wand and other weather conditions all create vibrations How strongly the instrumentation is influenced depends on where it is in the building and how far away it is from the vibration sources.

Isolation for vibration critical applications
Over the past 25 years, two technologies have gained prominence for their ability to Isolate vibrations Influencing nano-level Instrumentation, namely active vibration isolation (also known as electronic-force cancellation) and negative-stiffness vibration isolation {also known as passive vibration isolation).

Both active and negative-stiffness vibration isolation are uniquely equipped for applications where structures smaller than a micrometre need to be produced or measured. These technologies provide functionality that is typically not achievable with pneumatic vibration isolation tables.

Full article: Comparing systems...

Press Release:
New Ultra-Thin CT-2 Low-Frequency Vibration Isolation Platform Adapts
to Space Constraints in Critical Micro- and Nano-Microscopy
(replaces the CT-1)

Full release...

You might have thought, maybe for only a few moments, that your audio system was sounding especially good. With that feeling, you would have rated the sound a top score of "10". Then those magical moments ended and your system returned to it's normal - but still good - performance level. Well, folks, the Minus K CT-2 Isolation Platform could raise your system score to an "11" and keep it there! Highly recommended for systems that are already high performance and where you want to coax the maximum performance from your audio investment....

Dr. David L. Platus is President and Founder and is the principal inventor of the technology. He earned a B.S. and a Ph.D. in Engineering from UCLA, and a diploma from the Oak Ridge School of (Nuclear) Reactor Technology. Prior to founding Minus K® Technology he worked in the nuclear, aerospace and defence industries conducting and directing analysis and design projects in structural-mechanical systems. He became an independent consultant in 1988. Dr. Platus holds over 20 patents related to shock and vibration isolation.

Ultra-Thin 2.7" High CT-2 Product Attributes:
  - Isolation performance is typically 10 to 100 times better than air systems
  - No air or electric power is required
  - Nothing to wear out
  - No maintenance

A complete description of the patented Negative-stiffness design can be found on the Technology page of the manufacturers Web site. The Minus K platform is completely silent and requires no pumps or power. The CT-2 model platforms are available for different weight ranges of payload, or supported weight. The 40CT-2 model, while not specifically listed on the Web page, was perfect for the Clearaudio Ovation turntable used for this review. The platform dimensions are 18" W x 20" D x 2.7" H, with a weight of about 30 pounds. Different models, for different payloads, range in price from $4,650 to about $5,250. In my system, the platform was installed 20" W x 18" D, which placed the adjustment crank on the 18" left side.

The horizontal frequency of ~1.5 Hz is achieved at or near the upper limits of the payload range. The vertical frequency is tunable to 0.5 Hz throughout the payload range. What this means is that any very low frequency vibrations that are not blocked or absorbed by the Minus K platform are several orders of magnitude below what your phono cartridge, or even the best subwoofers, can process.

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Manufacturers need to control processes to produce a consistent, reliable product. Where precision surface engineering is required, surface measurement may be a key part of maintaining control of the process, by checking output to see that the process is not outside of specification.

3D non-contact surface analysis is widely used in the industry for the measurement of small displacements and surface irregularities. It delivers the ultimate in high accuracy and repeatable and traceable measurement. When built into microscopy equipment, employing 3D laser scanning or structured light, these systems report the surface condition of a product with more accuracy than any other methodproviding nanometer-level profile measurements of height, width, angle, radius, volume, and roughness. Such precision measurement systems allow users to improve product quality and reliability, and increase manufacturing consistency and production yields.

Low-Frequency Vibration
When measuring at such high levels of precision, any instrument can be negatively affected by low-frequency vibrations generated within a manufacturing facility. These can distort measurements and impact imaging and measurement data

One company that has great familiarity with the manufacturing environment and 3D surface measurements is Keyence Corporation--a leading supplier of sensors, measuring systems, laser markers, microscopes, and machine vision systems worldwide.

We have many customers with high-precision 3D measurement systems operating in high-vibration environments, performing microscopy evaluation at 30,000 times magnification, looking at nanometer-level surface features, said Evan Eltinge, Senior Sales Engineer Surface Analysis Team, with Keyence Corporation of America. At that level of detail, and in that environment, if measures are taken to reduce vibration it improves the quality of the data.

Without proper isolation surface measurements occurring at 3,000 to 5,000 times magnification, the vibration could contribute to image blurring and loss of image quality, continued Eltinge.

Vibration can be caused by a multitude of factors within a plant; every structure is transmitting noise. Within the building itself, production machinery, forklift trucks, the heating and ventilation system, fans, pumps, compressors, and elevators are just some of the mechanical devices and equipment that create low-frequency vibration. Depending on how far away the surface measurement instrumentation is from these vibration sources, and where inside the structure the instrumentation is locatedwhether on the production floor or in a loftwill determine how strongly the instrumentation will be influenced.

External to the building, the equipment can be influenced by vibrations from truck movement, road traffic, nearby construction, loud noise from aircraft, and even wind and other weather conditions that can cause movement of the structure.

Vibration Isolation Options for 3D Surface Analysis...

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