The SCARA acronym stands for Selective Compliant Assembly Robot Arm or Selective Compliant Articulated Robot Arm.
In general, traditional SCARA’s are 4-axis robot arms, i.e., they can move to any X-Y-Z coordinate within their work envelope. There is a fourth axis of motion which is the wrist rotate (Theta-Z). The ‘X’, ‘Y’ and the The ‘Z’ movements are obtained with three parallel-axis rotary joints. The vertical motion is usually an independent linear axis at the wrist or in the base. SCARA robots are used in assembly operations where the final move to insert the part is a single vertical move. Component insertion into printed circuit boards is an example. This is often called “vertical assembly”.
They are very common in pick-and-place, assembly, and packaging applications. The electronic printed circuit board industry, in particular, use large numbers of SCARAs for placing semiconductor ICs and other components on the circuit boards of computers and related equipment.
By virtue of the SCARA’s parallel-axis joint layout, the arm is slightly compliant in the X-Y direction but rigid in the ‘Z’ direction, hence the term: Selective Compliant. This is advantageous for many types of assembly operations, i.e., inserting a round pin in a round hole without binding.
The second attribute of the SCARA is the jointed two-link arm layout similar to our human arms, hence the often-used term, Articulated. This feature allows the arm to extend into confined areas and then retract or “fold up� out of the way. This is advantageous for transferring parts from one cell to another or for loading/ unloading process stations that are enclosed.
SCARA’s are generally faster and cleaner than comparable Cartesian systems. Their single pedestal mount requires a small footprint and provides an easy, unhindered form of mounting. On the other hand, SCARA’s can be more expensive than comparable Cartesian systems and the controlling software requires inverse kinematics for linear interpolated moves. This software typically comes with the SCARA though and is usually transparent to the end-user.
| Title | : | SCARA Robot |
| Category | : | Robotics Articles. |
| Tags | : | robot, robot scara, robotics, robotics article, scara, SCARA Robot, |
The word robotics was derived from the word robot, which was introduced to the public by Czech writer Karel Čapek in his play R.U.R. (Rossum's Universal Robots), which premiered in 1921.
According to the Oxford English Dictionary, the word robotics was first used in print by Isaac Asimov, in his science fiction short story "Liar!", published in May 1941 in Astounding Science Fiction. Asimov was unaware that he was coining the term; since the science and technology of electrical devices is electronics, he assumed robotics already referred to the science and technology of robots. In some of Asimov's other works, he states that the first use of the word robotics was in his short story Runaround (Astounding Science Fiction, March 1942). However, the word robotics appears in "Liar!"