How Robots Work

When many people hear the word “robot”, words such as “cool appearance”, “powerful function” and “high-end” will appear in their minds. They think that robots are as high-end and dazzling as the “Terminator” in science fiction movies. cool. In this article, we will explore the basic concepts of robotics and understand how robots accomplish their tasks.
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1. The components of the robot

At the most basic level, the human body consists of five main components:

(1) Body structure

(2) The muscular system, used to move body structures

(3) Sensory systems, used to receive information about the body and surrounding environment

(4) Energy sources, used to power muscles and senses

(5) Brain systems, which process sensory information and direct muscle movements Of course, humans also have some intangible characteristics, such as intelligence and morality, but on a purely physical level, the list is quite complete. The components of a robot are very similar to those of a human being. A typical robot has a movable body structure, a motor-like mechanism, a sensing system, a power source, and a computer “brain” that controls all these elements. Essentially, robots are “animals” made by humans, which are machines that mimic the behavior of humans and animals.

Bionic Kangaroo Robot

Robots can be defined in a wide range, ranging from industrial robots for factory services to household cleaning robots. By the broadest current definition, something is a robot if it is considered a robot by many people. Many roboticists (people who build robots) use a more precise definition. They stipulate that the robot should have a reprogrammable brain (a computer) to move its body. By this definition, robots differ from other mobile machines, such as cars, by their computing element. Many newer cars have an on-board computer, but only use it to make minor adjustments. The driver directly controls most parts of the vehicle through various mechanisms. And robots are different from ordinary computers in terms of physical characteristics. They are each connected to a body, which is not the case with ordinary computers.

Most robots do share some common traits

First, almost all robots have a body that can move. Some have only motorized wheels, while others have a large number of moving parts, usually made of metal or plastic. Similar to the human skeleton, these individual parts are connected by joints. The wheels and axles of the robot are connected by some kind of transmission. Some robots use motors and solenoids for transmission; others use hydraulic systems; and still others use pneumatic systems (systems powered by compressed gas). Robots can use any type of transmission described above. Second, the robot needs an energy source to drive these transmissions. Most robots will run on batteries or a wall outlet for power. Additionally, hydraulic robots require a pump to pressurize the liquid, while pneumatic robots require a gas compressor or compressed gas tank. All actuators are connected to an electrical circuit by wires. This circuit directly powers the electric motor and solenoid, and operates electronic valves to activate the hydraulic system. Valves control the path of pressurized fluid through a machine. For example, if the robot were to move a hydraulically powered leg, its controller would open a valve that leads from a hydraulic pump to a cylinder on the leg. The pressurized fluid will push the piston, rotating the leg forward. Typically, robots use pistons that provide bi-directional thrust to move parts in both directions. The robot’s computer controls everything connected to the circuit. To move the robot, the computer turns on all the motors and valves needed. Most robots are reprogrammable. To change a robot’s behavior, you simply write a new program into its computer. Not all robots have sensing systems. Very few robots have vision, hearing, smell or taste. One of the most common senses a robot has is kinesiology, or its ability to monitor its own movement. In the standard design, the robot’s joints are fitted with grooved wheels. On one side of the wheel is an LED that sends a beam of light through the groove and onto a light sensor on the other side of the wheel. The grooved wheels turn when the robot moves a particular joint. The grooves will block the beam during this process. An optical sensor reads the pattern of flickering beams and sends the data to a computer. Based on this pattern, the computer can accurately calculate how far the joint has rotated. The same basic system is used in a computer mouse. These are the basic building blocks of a robot. There are countless ways that roboticists can combine these elements to create robots of infinite complexity. Robotic arms are one of the most common designs.

2. How does the robot work?

The term “robot” in English comes from the Czech word robota, usually translated as “forced laborer”. It’s an apt description of most robots. Robots in the world are mostly used to do heavy repetitive manufacturing work. They are responsible for those tasks that are very difficult, dangerous or boring for humans. The most common manufacturing robot is the robotic arm. A typical robotic arm consists of seven metal parts connected by six joints. A computer turns stepper motors attached to each joint to control the robot (some large robotic arms use hydraulic or pneumatic systems). Unlike normal motors, stepper motors move precisely in increments. This allows the computer to move the robotic arm so precisely that it repeats the exact same motion over and over again. The robot uses motion sensors to make sure it moves exactly the right amount. The six-jointed industrial robot closely resembles a human arm, with the equivalent of a shoulder, elbow and wrist. Its “shoulders” are usually mounted on a fixed base structure (rather than a moving body). This type of robot has six degrees of freedom, that is, it can turn in six different directions. In contrast, the human arm has seven degrees of freedom.
A joint of a six-axis industrial robot

The role of the human arm is to move the hand into different positions. Similarly, the role of the robotic arm is to move the end effector. You can mount a variety of end effectors on the robot arm for specific application scenarios. A common end effector that grips and moves different objects is a simplified version of the human hand. Robotic hands often have built-in pressure sensors that tell the computer how hard the robot is grasping a particular object. This keeps objects in the robot’s hands from falling or being crushed. Other end effectors include blowtorches, drills, and paint sprayers. Industrial robots are designed to perform the exact same job repeatedly in a controlled environment. For example, a robot might be tasked with screwing the lids on jars of peanut butter as they pass along an assembly line. To teach the robot how to do the job, a programmer uses a handheld controller to guide the robotic arm through a set of motions. The robot stores the exact sequence of movements in memory, and it repeats it every time a new can is delivered on the assembly line.

A robotic arm is one of the basic components used in building a car

Most industrial robots work on automotive assembly lines, assembling cars. Robots are much more efficient than humans at doing a lot of this work because they are so precise. No matter how many hours they’ve been in the job, they still drill holes in the same places and drive screws with the same force. Manufacturing robots also play a very important role in the computer industry. Their incredibly precise hands can assemble a tiny microchip. Robotic arms are relatively easy to manufacture and program because they only work in a limited area. Things get a little more complicated if you’re sending your robot to the vast outside world. The first challenge is to provide a viable motion system for the robot. If the robot only needs to move on flat ground, wheels or tracks are often the best choice. They are also suitable for rougher terrain if the wheels and tracks are wide enough. But robot designers often want to use leg-like structures because they are more adaptable. Creating legged robots can also help equip researchers with knowledge of natural kinematics, a beneficial practice in the field of biological research. Robot legs are usually moved back and forth by hydraulic or pneumatic pistons. The individual pistons are attached to different leg parts, like muscles attached to different bones. Getting all these pistons to work together in the right way is certainly a challenge. In infancy, the human brain has to figure out which muscles need to contract simultaneously in order to walk upright without falling over. Likewise, a robot designer must figure out the correct combination of piston movements for 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 the robot’s motion needs to be corrected.

Boston Dynamics’ newly upgraded Atlas humanoid robot

The movement mode of bipedal walking itself is unstable, so it is extremely difficult to realize in the manufacture of robots. In order to design robots that walk more stably, designers often turn their attention to the animal kingdom, especially insects. Insects have six legs, and they tend to have extraordinary balance and adaptability to many different terrains. Certain mobile robots are remotely controlled, allowing humans to direct them to do specific jobs at specific times. The remote control unit can communicate with the robot using connecting wires, radio or infrared signals. Telerobots, often called puppet robots, are useful for exploring environments that are fraught with danger or inaccessible to humans, such as the deep ocean or inside a volcano. Some robots are only partially controlled by remote control. For example, an operator might instruct a robot to go to a specific spot, but not guide it on its way, allowing it to find its own way.

NASA develops remote-controllable space robot R2

Autonomous robots can act autonomously without relying on any human controller. The basic idea is to program a robot to respond in a certain way to external stimuli. The extremely simple crash-response robot illustrates this principle well.

The robot has a collision sensor that checks for obstacles. When you start the robot, it generally zigzags along a straight line. When it hits an obstacle, the force of the impact acts on its crash sensors. Each time there was a collision, the robot was programmed to instruct it to back up, turn right, and move on. According to this method, the robot changes its direction whenever it encounters an obstacle. Advanced robots use this principle in more sophisticated ways. Robotics experts will develop new programs and sensing systems to create more intelligent and sentient robots. Today’s robots can perform in a variety of environments. Simpler mobile robots use infrared or ultrasonic sensors to sense obstacles. These sensors work like an animal’s echolocation system: The robot emits a sound signal (or a beam of infrared light) and detects reflections of the signal. The robot calculates the distance between it and the obstacle based on the time it takes for the signal to reflect. More advanced robots use stereo vision to see the world around them. Two cameras give the robot depth perception, while image recognition software gives the robot the ability to locate objects and recognize various objects. The robot can also use microphones and scent sensors to analyze its surroundings. Certain autonomous robots can only work in limited environments with which they are familiar. For example, lawn-mowing robots rely on buried landmarks to determine the extent of grass fields. Robots used to clean offices require maps of buildings to move between locations. More advanced robots can analyze and adapt to unfamiliar environments, even areas with rough terrain. These robots can associate specific terrain patterns with specific actions. For example, a rover robot uses its vision sensors to generate a map of the ground ahead. If the map shows a rough terrain pattern, the robot knows it should go another way. Such a system would be very useful for exploration robots working on other planets. An alternative robot design uses a looser structure, introducing randomization. When the robot gets stuck, it moves its appendages in various directions until its movements have an effect. Instead of a computer programming everything, it uses force sensors and actuators that work together to accomplish tasks. This is similar to when ants try to bypass obstacles: ants do not seem to be decisive when they need to pass obstacles, but keep trying various methods until they bypass obstacles.

3. Homemade robot

In the final sections of this article, we take a look at the most compelling areas in the robotics world: artificial intelligence and research robotics. Experts in these fields have made great strides in robotics over the years, but they are not the only makers of robots. For decades, a small but passionate hobby has been building robots in garages and basements around the world. Home-made robots are a burgeoning subculture with considerable influence on the internet. Amateur roboticists assemble their creations from a variety of commercial robotics tools, mail-order parts, toys, and even vintage VCRs. Like professional robots, home-made robots come in many varieties. Some robotics enthusiasts, who can only work on the weekends, have created very elaborate walking machines, while others have designed domestic robots for themselves, and some enthusiasts are keen to build competitive robots. Among competitive robots, the most familiar are remote-controlled robot warriors, like the ones you see on the show BattleBots. These machines aren’t really “true robots” because they don’t have reprogrammable computer brains. They are just enhanced remote control cars. More advanced competitive robots are controlled by computers. For example, a soccer robot plays a small soccer game without any human input. A standard robot soccer team consists of several individual robots that communicate with a central computer. The computer “sees” the entire pitch through a video camera and uses color to identify footballs, goals, and players from their own and opposing teams. The computer processes this information all the time and decides how to direct its team.

Adaptability and Versatility

The personal computer revolution was marked by its remarkable adaptability. Standardized hardware and programming languages allow computer engineers and amateur programmers to build computers for their specific purposes. Computer parts are somewhat like craft supplies, and their uses are endless. Most robots to date are more like kitchen appliances. Roboticists make them specialized for specific purposes. But their adaptability to completely different application scenarios is not very good. this is changing