User:Phelps1513/sandbox/Quantum tunneling composite

Quantum tunneling composite (QTC) is an electrically conductive polymer used as a pressure switch or sensor. Used like a light dimmer switch for a light bulb, QTCs with a greater amount of pressure applied with have a higher concentration of electron flow. In its unstressed state, QTC acts as an electrical insulator but when sufficient amount of pressure is applied, it becomes a metal-like conductor. QTCs were discovered in 1997 by technician David Lussey while he was searching for a way to develop an electrically conductive adhesive. Lussey founded Peratech Ltd, a company devoted to research work and usage of QTCs. Peratech Ltd. and other companies are working on developing quantum tunneling composite to improve the touch technology the world faces. QTCs are safe to use in dangerous environments where materials may explode, such as space.

Introduction
Quantum tunneling composites are combinations of polymer composites with elastic, rubber-like properties, elastomer, and metal particles (nickel)l. Due to a no air gap in the sensor, contamination or interference between the contact points is impossible. There is also little to no chance of arcing, electrical sparks between contact points. In the QTC's inactive state, the conductive elements are too far from one another to pass electron charges. Thus, current does not flow when there is no pressure on the quantum-tunneling composite. A characterization of a QTC is its spiky silicon covered surface. The spikes do not actually touch, but when a force is applied to the QTC, the spikes move closer to each other and a [quantum] effect occurs as a high concentration of electrons flow from one spike tip to the next. The electrical current stops when the force is taken away.

Types
QTCs come in different forms and each form are used differently but have similar resistance change when deformed. QTC pills are the most commonly used type of QTC. Pills are pressure sensitive variable resistors. The amount of pressure applied is proportionate to the amount of electrical current passed. QTC pills can be used as input sensors which responds to an applied force. These pills can also be used in devices to control higher currents than that of QTC sheets. Another form of QTC are sheets. These sheets are composed of three layer: a thin layer of QTC material, a conductive material, and a plastic insulator. QTC sheets allows a quick switch from high to low resistance and vice versa.

Advantages

 * Flexible: It is possible for QTCs to be in any shape or size. This makes QTC materials possible
 * Durable: Since there are no moving parts of a quantum tunneling composite, it does not wear out or break apart. QTCs are proven mechanically strong. They've been tested under various pressures and temperatures and they are still capable of performing the needed functions.
 * Energy conservable: When it is in a state of rest, i.e. no pressure is on the QTC, no power is used. No electrical current is present and no electron charge is passed. The current will flow only when a force, pressure, is put upon the QTC.
 * Versatile: It is possible for QTCs to be made in any shape and size. This allows flexibility for The unique properties, such as the spikes and no air gap, allow QTC material to be used in vast areas such as textile, sports, medicine, automotive, etc.

Applications
QTCs were used to provide fingertip sensitivity in NASA's Robonaut. Robonaut was able to survive and send detailed feedbacks from space. The sensors on the human-like robot was capable tell how hard and where it was gripping something.

Quantum tunneling composites are relatively new and are still being researched and developed on. The following are possible uses for QTCs:
 * Textile : QTCs can be integrated as switches in sporting clothes to control music players. The textile can be made into a foldable piano keyboard.
 * Sporting materials such as training dummies or fencing jackets can be covered in QTC material. Sensors on the material can relay information on the force of an impact.
 * Mirror and window operation such as gesture, stroke, or swipe can be used on automotive. Depending on the amount of pressure applied from the gesture, the car parts will adjust to the desired setting at either a fast speed or a slow speed. When more pressure is applied, the faster the operation will take.
 * Blood pressure cuffs: QTCs in blood pressure cuffs reduces inaccurate readings from improper cuff attachment. The sensors tell how much tension is needed to read a person's blood pressure.