Smart bullet

Smart bullet is a term that has been used to describe several theoretical and prototype bullets. The "smart" part comes from the bullet doing something other than simply following its given trajectory, e.g. turning, speeding up, slowing down, sending data, etc. The patent number 5,788,178 for the guided bullet is held by Rolin F. Barrett Jr., of North Carolina, USA.

Types of smart bullets
In 2012 Sandia National Laboratories announced a self-guided bullet prototype that could track a target illuminated with a laser designator. The bullet is capable of updating its position 30 times a second and hitting targets over a mile away.

Changing trajectory
One kind of smart bullet is a projectile that is capable of changing its course during flight. One use of this would be to enable soldiers to stay behind protective cover and shoot around corners. One implementation uses a muscle wire inside the bullet. The wire shortens or lengthens, causing the bullet to bend. Another implementation uses a spoiler and micro gyro to control the bullet.

Navigating
Honeywell Aerospace has produced inertial measurement units based on MEMS and microelectronics technologies that it claims can survive the shock of being fired out of a gun.

Transmitting data
Another smart bullet is one that can transmit data about the location into which it has been fired. A prototype has been created by researchers at the University of Florida in Gainesville, Florida, USA with funding from Lockheed Martin. The bullet (projectile) has a sensor inside of it that can send wireless data up to 70 meters.

Limiting range
Another smart bullet is one that self-destructs within a limited range. This would be used to minimize collateral damage of a bullet in case of a miss. For example, hunting near a populated area. This would involve either change in course into the ground, or near vaporization.