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Robotic arm

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A robotic arm is a programmable mechanical device designed to mimic the functions of a human arm.

Industrial robots-transparent
Industrial robots-transparent

These machines are often part of a much larger, complex robot system. The structure of a robotic arm consists of several parts called links. These links are connected by joints that allow for different types of movement. Some joints provide rotational motion, which allows the arm to turn. Other joints allow for translational displacement, which is movement in a straight line. The sequence of these connected links is known as a kinematic chain.

Futur en Seine 2012 51
Futur en Seine 2012 51

The very end of this kinematic chain is called the end effector. This component is analogous to a human hand and is used to perform specific tasks. Depending on the job, an end effector might be designed for welding, spinning, or gripping. While people often call this part a "robotic hand," that term is sometimes avoided in technical settings. To move accurately, engineers focus on the degrees of freedom in the arm. This term describes the number of independent ways the arm can move. Usually, the number of degrees of freedom matches the number of joints. An arm requires at least six degrees of freedom to reach any specific pose. This pose includes both the position and the orientation of the hand in three-dimensional space.

To control these complex movements, scientists use a mathematical process called inverse kinematics. This process calculates the necessary configuration of the arm to reach a desired pose. It specifically determines the required joint angles to place the end effector in a certain spot. There are several distinct types of robotic arms used in industry today. Cartesian or gantry robots use three prismatic joints that align with a Cartesian coordinate system. They are often used for assembly or applying sealant. Cylindrical robots use axes that form a cylindrical coordinate system for tasks like spot welding. Spherical or polar robots use a polar coordinate system for gas welding or die casting.

Dobot- A Robot arm
Dobot- A Robot arm

Other specialized designs include the SCARA robot, which uses two parallel rotary joints to move within a plane. Articulated robots feature at least three rotary joints and are common in spray-painting. Parallel robots use concurrent joints and can serve as mobile platforms for flight simulators. There are also anthropomorphic robots, which are shaped to resemble a human hand with independent fingers and thumbs. A special category is the collaborative robot, or "cobot." Unlike traditional industrial robots that are isolated from humans, cobots are designed to work alongside people. They use lightweight materials, rounded edges, and sensors to ensure safety. This allows them to assist in research, material handling, and quality inspection.

Several major companies have shaped the history of robotics. FANUC was established in Japan in 1972 and has shipped over 1 million robots as of 2023. In 2022, the VW Group purchased 1,300 FANUC arms for automobile production. Yaskawa was established in Japan in 1915 and began developing the MOTO arm series in the 1960s. Their first Motoman-L10 arm entered production in 1977, and they sold over 500,000 Motoman robots by 2021. KUKA, a German company founded in 1898, began industrial robot development in 1971. They introduced FAMULUS in 1973, which was the first electric six-axis robot arm. In 2008, KUKA released the KR 1000 Titan, the first arm capable of lifting 1000 kilograms.

Industrial robots-transparent
Industrial robots-transparent

Robotic arms are essential tools in space exploration and planetary science. The Canadarm and its successor, Canadarm2, are famous multi-degree-of-freedom arms used in orbit. These arms have been used for satellite deployment and inspecting the Space Shuttle.

STS-3 Canadarm captures PDP
STS-3 Canadarm captures PDP

On Mars, the Curiosity and Perseverance rovers utilize robotic arms for exploration. The Perseverance rover even has a smaller sample caching arm hidden inside its body. The InSight lander used a robotic arm called the IDA to move instruments on the Martian surface.

Insight seisanimate
Insight seisanimate

In deep space, the OSIRIS-REx spacecraft used a robotic arm called TAGSAM to collect a sample from an asteroid.

Modern advancements are driven by artificial intelligence and machine learning. These technologies allow arms to identify and control items even in unstructured surroundings. Vision-based AI systems help with motion planning and adaptive grasping. This makes robotic arms much more effective in medical surgery, logistics, and agriculture. In healthcare, AI-driven arms increase stability during delicate, minimally invasive surgeries. In warehouses, they help with sorting and packaging to improve efficiency. New technologies like edge computing allow robots to interpret sensor data in real time. This improves reaction times in fast-paced industrial sectors and helps robots become more autonomous.

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File:STS-3 Canadarm captures PDP.jpg
STS-3 Canadarm captures PDP.jpg
File:NASA Webb Telescope Mirrors Installed with Robotic Arm Precision (24544051132).jpg
NASA Webb Telescope Mirrors Installed...
File:HTV-6 final approach towards the International Space Station (3).jpg
HTV-6 final approach towards the...
File:Industrial robots-transparent.gif
Industrial robots-transparent.gif
File:Méshumans-optimitzaciódelacriança.jpg
Méshumans-optimitzaciódelacriança.jpg
File:Uarm metal wiki2.jpg
Uarm metal wiki2.jpg
File:Blueblack preview featured.jpg
Blueblack preview featured.jpg
File:Insight seisanimate.gif
Insight seisanimate.gif
File:Futur en Seine 2012 51.jpg
Futur en Seine 2012 51.jpg
File:Dobot- A Robot arm.png
Dobot- A Robot arm.png
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