Nano Final

INTRODUCTION • Nanorobot is intended for treatment and/or of medicinal problems like:  Tumors  Asteriosclerosis  Blood clots  Accumulation of scar tissue

Construction  Size  Methods of entry  Means of propulsion  Control device  Power source  Removal of device afterwards

Factors to consider How to  Introduce the device into body  Move the device around the body  Know where the device should go  Control the device  Power the device  Know what must be done  Remove the device

How to introduce the device into the body we are gaining access through circulatory system  Smaller the machine the better  Accessing through large diameter artery.

How to access the device around the body we are gaining access through circulatory system Possibilities:  Must be carried to site of operation  Must be propelled

Carrying to site of operation It is done by normal blood flow Limits  Cannot be used in tumors and blood clots  Cannot be made stagnant

Must be propelled Requirement The device must be able to  move at a practical speed against the flow of blood.  move when blood is pooling rather than flowing steadily.  move in surges, so as to be able to get through the heart without being stuck, in the case of emergencies.  to react to changes in blood flow rate so as to maintain position, or somehow anchor itself to the body so as to remain unmoving while operating.  change direction laterally, so as to navigate the bloodstream.

Methods of propulsion • PROPELLERElectric motor of size 1/64th of an inch on a side Use shrouded blade design to avoid damage to surrounding tissue It is simple, well understood and exists exists since 1960.

How do we know where the device should go Sensor is used to locate position of microrobot They are of two typesinternal external

Internal sensor • It is used to navigate site of unwanted tissue. • It is used to distinguish between healthy & unwanted tissue.

External sensor Used to  determine location of operation site.  gain a idea of where the microrobot is in relation to that tissue. There are many techniques like  Ultrasonic  MRI  IR

Ultrasonic  in active mode, a ultrasonic beam is beamed into the body, reflected back and received signal is processed.  In passive mode, a ultrasonic signal of very specific pattern is generated by microrobot.

IR rays  In passive mode, various tissues in body generate signals & can be detected & interpreted by external sensor.  In the active mode, a signal is generated from outside the body .It is allowed to reflect from/pass through tissues and the result is interpreted.  The IR technique is more practical.

How do we control the device By means of internal sensor They are of two types: used to find final navigation used during actual operation.

How do we control the device They are of following technique chemical spectroscopic UHF

spectroscopic  It involves taking continuous small samples of surrounding tissues & analyzing them for appropriate chemicals.  Done by laser diode/electric arc to vaporize small amount of tissues.  Side effects are minimum.  Power requirement can be met by capacitors.  Equipment has no moving parts.

Means of treatment There are different types  Break clump of substance & eliminate it.  Destroy the substance and allow body to eliminate.  Use microrobot to physically remove the unwanted tissue.

Physical removal  Destroys the unwanted tissue in site  Avoids damaging the cancerous cells & releasing chemicals. Ultrasonicthe frequency of energy could be applied at specific frequency. needed to disrupt specific chemical bond. It destroys tumor producing chemicals.

Heat use heat to destroy cancerous cells  high level of heat is applied for a short time Microwave  It is designed to generate US signal & convert it into heat & kill the cancerous cells. From above a microrobot that can have several “treatment modules” is preferred.

power It is of 2 types.  source within the body  source external to the body source within the body  Body heat-uses body heat to power the microrobot.  The problem is that it requires energy gradient function.

Power from bloodstream  microrobot has electrodes mounted on outer casing that combines with blood stream to form battery.  Powered by means of fuel cell  Carry the required amount of energy using nuclear power source.

External source  Physical connection wire is used. wire must be flexible. wire must be thin  The power source must be electricity light

 Electricity needs a return path heating of wire is inevitable.  Light uses fiber optic cable. brittleness of wire must be taken into account.  Electricity is better option.

No physical connection  Ultrasonic-antenna is fixed in microrobot ultrasonic energy is beamed into the body & converted to electricity.  Induced magnetic-body is surrounded by magnetic field Field induces current within a rotating closed conducting loop in microrobot. Pinpoint heat source can be obtained.

Control system  Need to steer microrobot to where the sensor says  Need to know where to go  Need to know the route  Need to apply treatment effectively.  Need to reach outlet from body.

Applications  Kidney stones- by introducing microrobot into urethra we can break the stone directly.  Liverstone- by introducing microrobot into bile duct we can break the stone directly.  Burn & wound debriding-microrobot can be used to clean wound & burns. it is used to remove dirt & foreign particles.

conclusion • most or all of the engineering technologies to create a series of practical and effective microrobots already exist. Rather than keep our eyes fixed on the far future, let us start now by creating some actual working devices that will allow us to cure some of the most deadly ailments known, as well as advance our capabilities directly, rather than as the side effects of other technologies. A concerted development effort could have a working model of the microrobot ready within a year or two, and this would certainly advance the development of nanotechnology.