*3.9.1 Micro robotics*

In the field of small robotics, small power-efficient mechanical actuators and sensors are needed. With the use of piezoelectric actuators, building something as small as a robotic fly that can crawl and fly is technically feasible. In fact, a new field of robotic technology known as Micro Air Vehicles aims to build small drones the size of insects or birds that fly using flapping wings (**Figure 12**). They control surfaces just as birds and insects do. These types of feats in miniaturization are possible, in part, by using piezoelectric actuators.
