Actually, if you delve deeper into the robotics industry, you'll find that robots aren't quite like that. This article will teach you how to understand robots in one article and how they accomplish tasks.
Essentially, robots are "animals" created by humans; they are machines that mimic human and animal behavior. The components of a robot are very similar to those of a human. A typical robot has a movable body structure, a motor-like device, a sensing system, a power source, and a computer "brain" that controls all these elements.
The definition of a robot is very broad, ranging from industrial robots used in factories to home cleaning robots. According to the broadest definition, if something is considered a robot by many people, then it is a robot. Many robotics experts (those who create robots) use a more precise definition. They stipulate that a robot should have a reprogrammable brain (a computer) to move its body.
According to this definition, robots differ from other mobile machines (such as cars) in their computer elements. Robots differ from ordinary computers in their physical characteristics; each robot is connected to a body, unlike ordinary computers.
I. Common Characteristics of Robots
First, almost all robots have a movable body. Some are simply motorized wheels, while others consist of numerous movable parts, typically made of metal or plastic, connected by joints.
The wheels and axles of a robot are connected by some kind of transmission mechanism. Some robots use motors and solenoids as transmission mechanisms; others use hydraulic systems; and still others use pneumatic systems (systems driven by compressed gas). Robots can use any of these types of transmission mechanisms.
Secondly, robots need an energy source to power these transmission mechanisms. Most robots use batteries or wall outlets for power. Additionally, hydraulic robots require a pump to pressurize the fluid, while pneumatic robots require a gas compressor or compressed air tank.
All transmission mechanisms are connected to a circuit via wires. This circuit directly powers the electric motors and solenoids and operates electronic valves to activate the hydraulic system. The valves control the path of pressurized fluid within the machine. For example, if the robot wants to move a hydraulically driven leg, its controller opens a valve that connects the hydraulic pump to a piston cylinder on the leg. The pressurized fluid then pushes the piston, causing the leg to rotate forward. Typically, robots use pistons that provide bidirectional thrust, allowing components to move in both directions.
A robot's computer controls all components connected to the circuitry. To make the robot move, the computer activates all necessary motors and valves. Most robots are reprogrammable. To change the behavior of a robot, you simply write a new program into its computer.
Not all robots have sensory systems. Very few robots possess vision, hearing, smell, or taste. The most common sense a robot has is motion, its ability to monitor its own movement. In a standard design, a robot has grooved wheels mounted at its joints. On one side of the wheel is a light-emitting diode (LED) that emits a beam of light that passes through the groove and illuminates a light sensor located on the other side of the wheel. When the robot moves a specific joint, the grooved wheel rotates. During this process, the groove blocks the light beam.
An optical sensor reads the pattern of the light beam's flash and transmits the data to a computer. The computer can then accurately calculate the distance the joint has rotated based on this pattern. The basic system used in a computer mouse is the same.
These are the basic components of a robot. Robotics experts have countless ways to combine these elements to create robots of infinite complexity. The robotic arm is one of the most common designs.
II. How do robots work?
Most robots in the world are used for heavy, repetitive manufacturing work. They are responsible for tasks that are very difficult, dangerous, or tedious for humans.
The most common type of manufacturing robot is the robotic arm.
A typical robotic arm consists of seven metal parts connected by six joints. A computer rotates a stepper motor connected to each joint to control the robot (some large robotic arms use hydraulic or pneumatic systems).
Unlike conventional motors, stepper motors move precisely in incremental increments. This allows the computer to move the robotic arm with pinpoint accuracy, enabling it to continuously repeat the exact same movements. The robot uses motion sensors to ensure it moves exactly the correct amount.
This six-jointed industrial robot closely resembles a human arm, with sections corresponding to the shoulder, elbow, and wrist. Its "shoulder" is typically mounted on a fixed base structure (rather than a movable body). This type of robot has six degrees of freedom, meaning it can rotate in six different directions. In comparison, a human arm has seven degrees of freedom.
Industrial robots are specifically designed to perform the exact same task repeatedly in a controlled environment. For example, a robot might be responsible for screwing caps on peanut butter jars that are being transported on an assembly line. To teach the robot how to do this job, a programmer uses a handheld controller to guide the robotic arm through the entire sequence of movements. The robot stores the sequence of movements precisely in its memory, and then repeats the same movements whenever a new jar arrives on the assembly line.
Most industrial robots work on car assembly lines, assembling cars. When performing large volumes of this type of work, robots are far more efficient than humans because of their incredible precision. No matter how many hours they've worked, they can still drill holes in the same spot and tighten screws with the same force. Manufacturing robots also play a vital role in the computer industry. Their incredibly precise hands can assemble tiny microchips.
Robotic arms are relatively easy to manufacture and program because they only operate within a limited area. Things get more complicated when you're sending robots into the vast outside world.
The primary challenge is providing a viable locomotion system for the robot. If the robot only needs to move on flat ground, wheels or tracks are often the best option. If the wheels and tracks are wide enough, they can also be used on more rugged terrain. However, robot designers often prefer legged structures because they are more adaptable. Building legged robots also helps researchers understand the kinetics of nature, which is a valuable practice in biological research.
A robot's legs typically move back and forth driven by hydraulic or pneumatic pistons. These pistons are attached to different leg components, much like muscles attached to different bones. Getting all these pistons to work together correctly is undoubtedly a challenge. In infancy, the human brain must figure out which muscles need to contract simultaneously to prevent falls while walking upright. Similarly, robot designers must figure out the correct combination of piston movements related to walking and program this information into the robot's computer. Many mobile robots have a built-in balance system (such as a set of gyroscopes) that tells the computer when to correct the robot's movements.
Bipedal locomotion is inherently unstable, making it extremely difficult to implement in robot manufacturing. To design robots with more stable walking, designers often turn to the animal kingdom, especially insects. Insects have six legs and often possess extraordinary balance, allowing them to adapt easily to many different terrains.
Some mobile robots are remotely controlled, allowing humans to direct them to perform specific tasks at specific times. Remote control devices can communicate with the robot using cables, radio, or infrared signals. Remotely controlled robots, often called golem robots, are extremely useful for exploring dangerous or inaccessible environments, such as the deep sea or the interior of a volcano. Other robots are only partially remotely controlled. For example, an operator might instruct a robot to go to a specific location but not provide directions, allowing it to find its own way.
NASA develops R2, a remotely controlled space robot.
Autonomous robots can act independently without relying on any human controllers. The basic principle is to program the robot to react to external stimuli in a specific way. Extremely simple collision-response robots perfectly illustrate this principle.
This robot has a collision sensor to detect obstacles. When you start the robot, it generally moves in a zigzag pattern along a straight line. When it hits an obstacle, the impact is felt by its collision sensor. Each time a collision occurs, the robot's program instructs it to back up, turn right, and then continue moving forward. In this way, the robot changes its direction whenever it encounters an obstacle.
Advanced robots will utilize this principle in more sophisticated ways. Robotics experts will develop new programs and sensing systems to create robots with higher intelligence and stronger perception capabilities. Today's robots can perform admirably in a wide variety of environments.
Simpler mobile robots use infrared or ultrasonic sensors to detect obstacles. These sensors work similarly to an animal's echolocation system: the robot emits a sound signal (or a beam of infrared light) and detects the reflection of the signal. The robot then calculates the distance to the obstacle based on the time it takes for the signal to reflect.
More advanced robots use stereoscopic vision to observe the world around them. Two cameras provide depth perception, while image recognition software enables the robot to determine the location of objects and identify various objects. Robots can also use microphones and odor sensors to analyze their surroundings.
Some automated robots can only work in limited environments they are familiar with. For example, lawnmower robots rely on buried markers to define the boundaries of their lawns. Robots used to clean offices, on the other hand, need maps of the building to move between different locations.
More advanced robots can analyze and adapt to unfamiliar environments, even those with rugged terrain. These robots can associate specific terrain patterns with specific actions. For example, a rover robot might use its visual sensors to generate a map of the ground ahead. If the map shows an uneven terrain pattern, the robot will know to take an alternate route. Such systems are extremely useful for exploratory robots working on other planets.
One alternative robot design employs a looser structure, introducing randomization. When stuck, this robot moves its appendages in various directions until its actions produce an effect. It completes tasks through close collaboration between force sensors and transmission mechanisms, rather than being entirely guided by a computer program. This is similar to ants trying to navigate around obstacles: ants don't seem to make a decisive move when faced with an obstacle, but rather continuously try different approaches until they get around it.
III. Artificial Intelligence
Artificial intelligence (AI) is undoubtedly the most exciting and controversial field in robotics: everyone agrees that robots can work on assembly lines, but there is disagreement about whether they can possess intelligence.
Ultimately, artificial intelligence is the reproduction of human thought processes—an artificial machine possessing human-like intelligence. Artificial intelligence includes the ability to learn any knowledge, reasoning ability, language ability, and the ability to form its own opinions. Currently, robotics experts are far from achieving this level of artificial intelligence, but they have already made significant progress in limited areas of AI. Today, machines with artificial intelligence can already mimic certain specific elements of intelligence.
Computers have already acquired the ability to solve problems within limited domains. The execution process of solving problems using artificial intelligence is complex, but the basic principles are quite simple. First, an AI robot or computer gathers facts about a given situation through sensors (or human input). The computer compares this information with stored information to determine its meaning. Based on the collected information, the computer calculates various possible actions and then predicts which action will be most effective. Of course, the computer can only solve problems that its program allows it to solve; it does not possess general analytical capabilities. Chess computers are an example of such machines.
Some modern robots also possess limited learning capabilities. Learning robots can recognize whether a certain action (such as moving a leg in a certain way) achieves the desired result (such as navigating around an obstacle). The robot stores this information and, when it encounters the same situation again, will attempt to perform an action that will allow it to cope successfully. Similarly, modern computers can only do this in very limited situations. They cannot collect all types of information like humans. Some robots can learn by imitating human actions.
The real challenge of artificial intelligence lies in understanding how natural intelligence works. Developing AI is different from creating an artificial heart; scientists don't have a simple, concrete model to refer to. We know that the brain contains billions of neurons, and our thinking and learning are accomplished by establishing electrical connections between different neurons. However, we don't know how these connections enable higher-level reasoning abilities, or even the underlying principles of low-level operations. The brain's neural networks seem incomprehensibly complex.
Therefore, artificial intelligence is still largely theoretical. Scientists propose hypotheses about the principles of human learning and thinking, and then use robots to experiment with their ideas.
Just as the physical design of robots is a convenient tool for understanding animal and human anatomy, research into artificial intelligence helps us understand how natural intelligence works. For some robotics experts, this insight is the ultimate goal in robot design. Others envision a world where humans and intelligent machines coexist, with humans using various small robots for manual labor, healthcare, and communication. Many robotics experts predict that the evolution of robots will eventually make us completely cyborgs—humans fused with machines. There is reason to believe that future humans will implant their minds into robust robotic bodies and live for thousands of years!
Regardless, robots will play an important role in our daily lives in the future. In the coming decades, robots will gradually expand beyond industry and science into everyday life, much like the gradual popularization of computers in homes starting in the 1980s.
