A nanorobot is essentially a controllable machine at the nano meter or molecular scale and composed of nano-scale components. The field of nanorobotics studies the design, manufacturing, programming and control of the nano-scale robots constituting any passive or active nano structure capable of actuation, sensing, signaling, information processing, intelligence and having swarm behavior. In fact there are countless such machines that exist in nature and there is an opportunity to build more of them by mimicking nature.

Developments

The development in nanorobots are emerging with many aspects even for further future investigations. Basically, there are two distinct kind of nanorobot utilization, one is for the surgery intervention and the other is to monitor patients’ body. The nanorobots go along with specific controls, sensors and actuators depending on the type of biomedical applications and various research centers are building such nanorobots nowadays. Advances on diamondoid manufacturing are also being used for manufacturing nanodevices and building nanorobots. Due to the modern scientific capabilities, it has become easy for the scientists to create nanorobotic devices and interface them with the macro world for control.

Manufacturing

The nanorobots are invisible to naked eye and hard to manipulate and work with. Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) can be employed to establish a visual and haptic interface to enable to sense the molecular structure of these nano scaled devices. The nanorobots or nano machine components are difficult to fabricate and control challenges. Such devices have to operate in microenvironments with physical properties different from those encountered by conventional parts.

Molecular machines

Molecular machines use various biological elements whose function at the cellular level creates motion, force or a signal as machine components and these components perform their preprogrammed biological function in response to the specific physiochemical stimuli but in an artificial setting. In this way proteins and DNA could act as motors, mechanical joints, transmission elements, or sensors. If all these different components were assembled together in the proper proportion and orientation they would form nano devices with multiple degrees of freedom, able to apply forces and manipulate objects in the nanoscale world.

Applications

The nanorobots can be used to manipulate matter at the nano scale. Other applications range from medical to environmental sensing to space and military applications. Nanorobots can find application in molecular construction of complex devices, precise drug delivery to repair cells and fight tumor cells.

Control of Nanorobotic systems

The nano robotic systems can be controlled either internally or externally or as a hybrid control.

Internal Control

This is a traditional method. This type of control depends upon the mechanism of bio chemical sensing and selective binding of various bio molecules with various other elements. These molecules can be programmed for a particular kind of molecular interaction. The question of actively controlling the nanorobots using internal control mechanism is a difficult one. For achieving this internal control, the concept of molecular computers could be utilized to analyze the biological information, which could detect and treat cancer by producing a drug. This molecular computer is in generalized form and can be used for any disease which produces a particular pattern of gene expression related to it.

External Control

This type of control mechanism affects the dynamics of the nanorobot in its work environment through the application of external potential fields such as MRI for guiding the nano particles. MRI system is capable of generating variable magnetic field gradients which can exert force on the nanorobot in the three dimensions and hence control its movement and orientation. Other possibilities being explored are in the category of ‘hybrid’ control mechanisms where the target is located and fixed by an external navigational system but the behavior of the nanorobot is determined locally through an active internal control mechanism.