Science fiction used to be the only place where robots existed. However, with the lightning-fast way technology evolves, we are now living in a society where robots are used to do both basic and complex jobs, helping humans with tasks that are repetitive, dangerous, and difficult or even impossible to accomplish under normal circumstances.
Programmable robotic arms are among the most popular machines used today for these tasks. These usually work much like a human arm and can either be a stand-alone machine or a part of a more sophisticated robot – for example, the Mars Curiosity Rover has a robotic arm that helps with sample collection and preparation. There are various types of industrial robot arms that have since made fields like manufacturing, military surveillance and weaponry, medicine and healthcare, transportation, and research safer and more efficient.
Here are some examples of the most common types of robotic arms.
Articulated Robot Arm
This design features anywhere from two to ten or more joint structures, although most have at least four to six articulation points. Each additional joint, called an axis, provides an additional range of motion – the more axes there are, the more precise the robot arm can be. For example, bomb disposal robots have hand-like attachments that closely emulate the motions of the human hand. This can be used to open doors, for example, or handle or move sensitive munitions. Articulated robot arms are also commonly used in assembly lines, die casting, gas welding, and even spray painting.
Cartesian Robot Arm
Taking its name from the Cartesian plane, the Cartesian robots are also called rectilinear or gantry robots or arms. These robotic arms have three prismatic joints – the X, Y, and Z joints – that deliver linear motions along each axis. They may also have a wrist-like attachment on one end to provide rotational movement. Cartesian robots are popular in arc welding, assembly operations, and pick and place (P&P) machines.
Cylindrical Robot Arm
This type of robot arm has at least one rotary joint at its base, which provides rotational motion along its axis, and at least one prismatic joint, which provides linear motion and connects the links (usually three). The joints form a cylindrical coordinate system, making this type of robot arm valuable in industries that usually deal with tubes and cylindrical components. Other uses include die casting, spot welding, and even measuring accretion disks in astronomy.
Delta Robot Arm
A delta robot is a type of parallel robot (a type of robot with arms that have prismatic or rotary joints that converge onto a common base), distinguished by three arms built from jointed parallelograms. This structure maintains the orientation of the end effector, the part attached to the end of the robotic arm that does most of the work. Delta robots are capable of quick yet precise and delicate movements, which make them popular in the food processing and packaging, chemical, pharmaceutical, and electronics industries.
Polar or Spherical Robot Arm
This type of robot is configured to form a polar coordinate system using a combination of two rotary joints and one linear joint, connected to a singular base with a twisting joint. This results in a spherical-shaped work envelope and range of motions. Apart from gas and arc welding, polar robots are also used in environmental monitoring, planetary and underwater exploration, and rehabilitation and physical therapy machines.
SCARA Robot Arm
SCARA stands for Selective Compliance Assembly Robot Arm or Selective Compliance Articulated Robot Arm. Often used in high-speed assembly operations, packaging, and P&P machines, SCARA robots have a cylindrical design, with two parallel rotary joints that provide flexibility and suppleness (compliance) in a single plane.
Despite robots have been seen as a threat to job security, humans still have a leading edge over machines – things like the ability to improvise, critical thinking, and judgment give humans irreplaceable value even as they work alongside highly capable, efficient machines. The assistance these machines give to humans become an invaluable asset that makes modern living much more convenient for people and society in general.