This category of craft is fully controlled by a pilot using a ground station. Crafts of this type are preferred by hobbyists.

It is possible to increase the level of intelligence of a UAV so that it will neither be a fully autonomous vehicle, nor a fully remote controlled one. The pilot uses a remote control device to communicate between the quadcopter and the ground station but now the pilot does not fly the craft as if it's an RCV, the only thing that is required now is to set the points that it should pass (navigation points).

This category of craft has no pilot. All we need to do is connect the battery to the electronic system and let it fly. Quadcopters have numerous sensors, such as GPS, accelerometers, cameras, and many more. Every second, the controller gathers data from all the sensors and after calculations it autonomously decides how and where it should go according to the mission plan. These are extremely difficult to build, which is the reason why we prefer hybrid RCVs if we need a craft with autonomous functions.

Usually, any inexperienced hobbyist who is willing to build a quadcopter chooses the X shape, with four motors mounted at the ends. There are plenty of shapes and materials that can be used for this construction. Each has its own advantages and drawbacks, as it will be explained later on in the subsequent chapters. The X shape is the most common and a first attempt for almost everyone. However, a quadcopter can also be created in a Plus or H shape, as shown in the following figure:

Adding more than four motors will result in a different build that might also work. Vehicles like these are defined as hexa-copters or octo-copters depending on the number of motors used. It should be clear that we can only add two motors at a time; adding only one will not work due to the laws of physics, as will be explained later.