CHAPTER-4: How robots are made?

A robot basically contains a movable physical structure, a motor of some sort, a sensor system, a power supply and a computer "brain" which can control all of these elements. Robots are machines which can duplicate human and animal behavior. Most of robots have various qualities in general. Almost all robots have a movable body. Some only have motorized wheels and others have several movable segments, typically made of plastic or metal. Individual segments are connected together with joints like the bones of human body.

Robots spin wheels and pivot jointed segments with some sort of actuator. Robots use various types of actuator. Electric motors and solenoids are used in some robots as actuators. Hydraulic and pneumatic system are also used in different types of robots. Pneumatic is a system which is operated by compressed gases. In order to operate these actuators, a robot requires a power source. Most robots are operated either by battery or plug into the wall. For pressurizing the hydraulic fluid, a pump is required by a robot. An air compressor or compressed air tanks are required for pneumatic robots.

The actuators are electrically connected by wire into an electrical circuit. The circuit provides necessary powers to electrical motors and solenoids directly. By employing electrical valves, it triggers the hydraulic system. The valves regulate the pressurized fluid’s path through the machine. In order to move a hydraulic leg, for example, the controller of the robot would open the valve leading from the fluid pump to a piston cylinder attached to that leg. The pressurized fluid would extend the piston, rotating the leg forward. Usually, robots use pistons which can push both ways for moving their segments in two directions.

Everything associated with the circuit are controlled by the computer of the robot. The computer switches on all the necessary motors and valves for moving the robot. Most of robots are re-programmable. You can change the robot’s behavior of the robot by simply writing a new program to its computer.

Some robots have sensors which assist them to see, hear, taste and smell. The sense of movement is the most common robotic sense. A robot can monitor its own motion by utilizing this sensor. Slotted wheels are used in a standard design which are connected to the joints of the robot. An LED on one side of the wheel shines a beam of light through the slots to a light sensor on the other side of the wheel. The slotted wheel is turned on when the robot moves a particular joint. The slots break the light beam as the wheel spins. The light sensor reads the pattern of the flashing light and transmits the data to the computer. The computer can tell exactly how far the joint has rotated based on this pattern. These are the basic nuts and bolts of robotics. Scientists and engineers can create various types of robots by combining these elements in various ways.

Next Chapter: CHAPTER-5: How artificial intelligence works?