tech by munguychaitu

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                     Nanopolymer Technology

                              ABSTRACT
       Nanotechnology involves working with matter at the scale of one-
billionth of a meter (1 nanometer). It refers to the manipulation of matter on
the minutest scale, i.e. atoms and molecules.
       According to Moore’s law, the number of transistors on a chip
doubles every 18 months. Going by this law, current standards would no
longer be feasible. Carbon Nanotubes technology is under progress and it
will take quit a lot of time for practical implementation.

NEW NANOPOLYMER CONCEPT
       0’s and 1’s make up the digital information and we try to cram as
much information as possible. Our Nanopolymer setup uses thousands of
nano-sharp tips to punch indentations representing individual bits into a thin
plastic polymer film. The result is similar to a nanotech version of the 'punch
card' but this technology is re-writeable and may be able to store more than 3
billion bits of data in the space occupied by just one hole in a standard punch
card. The indentations that are left on the polymer film measure about 10
nanometers each and carry a digitized version of the data. A punched
indentation may refer to as 0 or 1. Practical implementation of this
technology is possible.

NANOPOLYMER ROBOTS
       NanoPolymerRobots are nanodevices that will be used for the purpose
of maintaining and protecting the human body against pathogens. This is at
present possible only with the above proposed technology. We have
designed the nanorobot structure.
        Proposed applications include Nanopolymer machine for mouthwash,
cream with tiny polymer robot for skin diseases, polymer soldier for immune
system and devices working in the bloodstream which could nibble away at
arteriosclerotic deposits, widening the affected blood vessels.

SMART POLYMER SHIRT
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With this new nanopolymer technology, even the finest textile fibres could
have sensors, computers, and motors embedded in the fabric. Likewise,
clothing would be smart enough to change according to ambient
temperature, i.e. it will keep us warm in winter or cool and dry in summer. It
can also monitor parameters like heart rate, respiratory rate, and body
temperature.
NANOTECHNOLOGY
INTRODUCTION
      Every living being is composed of matter. Matter is again the
composition of infinite atoms. The atoms cluster together to form molecules,
which, in turn, combine with several other molecules to form a basic
molecular structure. These are vital things to consider in the field of
nanotechnology. Nanotechnology involves working with matter at the scale
of one-billionth of a meter (1 nanometer). It refers to the manipulation of
matter on the minutest scale, i.e. atoms and molecules.

MOORE’S LAW
       According to Moore’s law, the number of transistors on a chip
doubles every 18 months, and new micro transistors are crammed onto the
tiny chipset for more raw performance. Going by this law, experts are of the
opinion that sooner than later the current standards would no longer be
feasible for further deployment and the hardware would be needed to change
considerably.

CARBON NANOTUBES
       All over the world scientists have been working with Carbon
Nanotubes for the last several years. Carbon Nanotubes are tiny cylindrical
structures made up of carbon atoms having unique properties. Nanotube
transistors can be made smaller than the smallest possible silicon transistor.
But this technology is under progress and it will take quit a lot of time for
practical implementation.

NEW NANOPOLYMER CONCEPT
       0’s and 1’s make up the digital information and we try to cram as
much information as possible. Our Nanopolymer setup uses thousands of
nano-sharp tips to punch indentations representing individual bits into a thin
plastic polymer film. The result is similar to a nanotech version of the
venerable data processing 'punch card' developed more than 110 years ago,
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but the differences are the 'Nanopolymer concept’ technology is re-writeable
(meaning it can be used over and over again), and may be able to store more
than 3 billion bits of data in the space occupied by just one hole in a standard
punch card. The indentations that are left on the polymer film measure about
10 nanometers each (each mark being 50,000 times smaller than the period
at the end of this sentence.) and carry a digitized version of the data.




            FIG1: Punching the polymer with the help of heated spikes




    FIG2: Silicon cantilevers with spikes ready for action on the polymer

      The core of the Nanopolymer project is a two-dimensional array of v-
shaped silicon cantilevers that are 0.5 micrometers thick and 70 micrometers
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long. At the end of each cantilever is a downward-pointing tip less than 2
micrometers long. We can go for a setup that contains a 3 mm by 3 mm
array of 4,096 (64 x 64) cantilevers, which can be created by silicon surface
micromachining. A sophisticated design ensures accurate leveling of the tip
array with respect to the storage medium and dampens vibrations and
external impulses.
       Time-multiplexed electronics, similar to that used in DRAM chips,
address each tip individually for parallel operation. Electromagnetic
actuation precisely moves the storage medium beneath the array in both the
x- and y-directions, enabling each tip to read and write within its own
storage field of 100 micrometers on a side.




            FIG3: Proposed setup for Nanopolymer technology

      The Nanopolymer functions on the principle of a parallel x/y scanning
of the entire cantilever array chip over the storage medium. As a part of a
feedback-controlled leveling scheme, three cantilevers at the periphery of
the array are dedicated as distance sensors. The signals they generate are
used to ensure that the tip-to-medium contact is maintained and controlled
while x/y scanning is performed for reading and writing
      For the operation of the device -- i.e. reading, writing, erasing and
overwriting -- the tips are brought into contact with a thin polymer film
coating a silicon substrate only a few nanometers thick. Bits are written by
heating a resistor built into the cantilever to a temperature of typically 400
degrees Celsius. The hot tip softens the polymer and briefly sinks into it,
generating an indentation. For reading, the resistor is operated at lower
temperature, typically 300 degrees Celsius, which does not soften the
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polymer. When the tip drops into an indentation, the resistor is cooled by the
resulting better heat transport, and a measurable change in resistance occurs.




              FIG4: Expected structure of cantilever with spike.


      To over-write data, the tip makes a series of offset pits that overlap so
closely their edges fill in the old pits, effectively erasing the unwanted data.

       While current data rates of individual tips are limited to the kilobits-
per-second range, which amounts to a few megabits for an entire array,
faster electronics will allow the levers to be operated at considerably higher
rates. This technology could support data rates as high as 1 - 2 megabits per
second.

       Power consumption greatly depends on the data rate at which the
device is operated. When operated at data rates of a few megabits per
second, Nanopolymer is expected to consume about 100 milliwatts, which is
in the range of flash memory technology and considerably below magnetic
recording.


       If this concept is achieved an areal density of 800 gigabits (billion
bits, Gb) per square inch, which translates to a potential capacity of about 2
gigabytes (billion bytes, GB) in an area of 3 mm-square. Further
improvement is also possible. In this way we can achieve Moore’s law with
ease.
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APPLICATIONS OF OUR TECHNOLOGY

NanoPolymerRobots
The development of advanced products requires more and more accuracy
and the tendency moves toward smaller components. These are fabricated
using the above technology. To handle this smaller objects we have
proposed a nano robot with 3 degrees-of-freedom with higher precison and
control system.
Architecture of nano robot:




                         Fig: The Nanorobot system

The system is composed of a robot operating under a light microscope or a
stereo SEM. A stereo vision module and probably additional sensors (laser
interferometer) will be used to locate the objects and the robot gripper. This
information is sent to the main control computer which will move the robot
in an appropriate way. The commands are given by a human operator
through a virtual reality-based user interface.
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       Stereo views, force and sound are among the feedback signals that
will be provided to the user. It will thus be possible to use the system either
as a teleoperated or as a semi-automatic mode of operation.
       In the latter, only final and/or intermediate goals will be specified by
the user, the control being made by the stereo vision feedback.
       In robotics, like in every controlled system, the final accuracy is
strongly linked to the resolution of the sensor and its location, the behavior
of the mechanics and the control algorithm used.

Sensors

For classical robots, the sensors are usually at the joint level. Assuming that
the links are highly rigid, a geometric model is calculated to transform the
sensors information into a position and orientation of the tool center point
(TCP) in an absolute cartesian frame. This technique leads to a poor
accuracy but to a good repeatability, most of the errors being due to offset
miscalibration and link deformation. If higher accuracy is needed, a
calibration is often proposed. However, when dealing with nanometer
precisions, many sources of errors are not predictable, and cannot be
corrected in a calibration process. It is then imperative to use a sensorable to
measure, with the desired resolution, the relative distance between the TCP
and the object to grasp. Among the sources of error that could affect the
precision of the robot we can list:

      friction, mechanical play
      thermal drift
      fabrication tolerances and misalignment
      mechanical deformations due to forces
      vibrations (internal and external) and noise
      sensor errors, miscalibration.

The ideal sensor would measure this relation with the highest possible
resolution (at least better than 10 nm), in 6 degrees-of-freedom (dof), and
with a very high bandwidth (> 10kHz).


Mechanics:

It is obvious that a good mechanics will lead to better performances of the
overall system and will simplify its control. We discuss in the following
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some important aspects to be aware of. If the sensor system is able to
measure directly the relation between the TCP and the object, the robot must
not be accurate anymore.
       The only requirement is a high resolution, that is the smallest
achievable step. This leads to completely new solutions that are much more
tolerant in fabrication and are easier to handle. A careful design is however
necessary and a special attention has to be put on the elimination of backlash
and Coulomb friction.

      The difference between the dynamic and static friction coefficients is
the cause of the stick-slip effect in classical mechanisms. This effect gives a
lower limit to the reachable resolution. It is very expensive and almost
impossible to go down to nanometers with such drives. New designs must be
found trying to avoid friction in the bearings or better, to avoid bearings.
Piezoelectric elements are well suited for that purpose. Several concepts
have been proposed to increase it while keeping the high precision.

Control




                              Fig: Control strategy

It will not be possible to acquire the new position at a high rate with the
vision system. In order to achieve an effective motion it is necessary to
move “blind” while the vision is calculating the new data. To assure a proper
operation and above all the stability of the arm, a fast joint position control is
needed. The resolution of the joint sensors must be as good or even better as
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the wanted system’s resolution, but locally only. The control loop will thus
be cascaded, like shown in figure.

Control with Real Time Vision Feedback

The 3 dof magnet-based micro-crawling machine described above has been
controlled successfully under a light microscope. The control setup consists
of a VME compatible 68020 microprocessor board and a vision board that
collects the information of a CCD camera mounted on the microscope. A
primitive user interface allows the operator to give commands to the system.



The system supports two modes:

Firstly, the robot can be driven directly with a space mouse(Logitech) used
as a 3D joystick. During the motion the operator is supplied with the original
image displayed on a video screen and with the 3 coordinates of the
calculated in 100ms by the low level vision system.

The second mode is called semi-automatic. It allows the user to freely
position a 3D cursor on the screen and then let the mechanism move toward
this new goal. In this case, the control loop is closed by the computer and not
by the operator who is just a supervisor. A new measured position is
provided every 100ms by the vision process. In-between, the robot moves
blindly. It is thus possible to control the mechanism inside the field of view
of the microscope.
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                           Fig: Nanocontrol system

FIELDS OF APPLICATION:

Some possible applications using NanopolymerRobots are as follows:

1. Mounting of hybrid chips (e.g. Laser diodes), microsensors and
micromachines

2. Positioning and mounting of optoelectronic devices

3. Microsurgery

4. Sorting of biological cells for diagnosis

OTHER APPLICATIONS:

1.     To cure skin diseases, a cream containing NanoPolymerRobots may
be used. It could remove the right amount of dead skin, remove excess oils,
add missing oils, apply the right amounts of natural moisturizing
compounds, and even achieve the elusive goal of 'deep pore cleaning' by
actually reaching down into pores and cleaning them out. The cream could
be a smart material with smooth-on, peel-off convenience.



2.    A mouthwash full of smart NanoPolymerMachines could identify and
destroy pathogenic bacteria while allowing the harmless flora of the mouth
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to flourish in a healthy ecosystem. Further, the devices would identify
particles of food, plaque, or tartar, and lift them from teeth to be rinsed
away. Being suspended in liquid and able to swim about, devices would be
able to reach surfaces beyond reach of toothbrush bristles or the fibres of
floss. As short-lifetime medical nanodevices, they could be built to last only
a few minutes in the body before falling apart into materials of the sort
found in foods (such as fibre).



3.     Medical nanodevices could augment the immune system by finding
and disabling unwanted bacteria and viruses. When an invader is identified,
it can be punctured, letting its contents spill out and ending its effectiveness.
If the contents were known to be hazardous by themselves, then the immune
machine could hold on to it long enough to dismantle it more completely.



4.     Devices working in the bloodstream could nibble away at
arteriosclerotic deposits, widening the affected blood vessels. Cell herding
devices could restore artery walls and artery linings to health, by ensuring
that the right cells and supporting structures are in the right places. This
would prevent most heart attacks.



SMART POLYMER SHIRT

       Wouldn’t it be really nice if any nasty stains are never ever got onto
our shirts? With this new nanopolymer technology, even the finest textile
fibres could have sensors, computers, and motors embedded in the fabric.
The micro granules that form the basic molecular structure are smaller than a
grain of sand, thereby forming a barrier that causes heavy liquids and stains
to gently roll off. The fabric sensors ensure that garments resists fading or
crumpling, and also monitor the body odour.
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                                                                Data bus
  Sensors



 Address
 bus




                         Multi function processor



       Likewise, clothing would be smart enough to change according to
ambient temperature, i.e. it will keep us warm in winter or cool and dry in
summer.
In the proposed block diagram the parameters monitored are heart rate,
respiratory rate, and body temperature. Also we can develop garments that
clean and mend themselves, and grow or shrink to fit a variety of shapes and
sizes.



CONCLUSION

      In this paper we have proposed a practically possible nanotechnology
named as Nanopolymer technology. It is feasible and can be easily
implemented compared to the Carbon nanotube which will take years to
come (More than 10 years). Vital applications that originated in our minds
and which makes use of this new technology are also mentioned in this
paper. Practical implementation of this concept leads to all of the above
wonders, and many more, are possible.

								
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