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SCARA arms

A four-axis arm that swings in a horizontal plane and plunges straight down — a fast, stiff way to pick, place and press parts on a flat bench.

  • SCARA
  • selective compliance arm

What it is

A SCARA arm has two rotary joints with vertical axes, so its shoulder and elbow swing sideways like a drafting lamp, plus a vertical slide and a wrist that twists the tool. SCARA stands for Selective Compliance Assembly Robot Arm: compliant sideways, so a peg finds its hole, but stiff up and down, so it can press parts home. The trade is reach for speed. It cannot tilt the tool, but it is typically quicker in its plane than an articulated arm of similar size.

Also called a selective compliance arm or a four-axis assembly robot. In this taxonomy it sits under Arm, and the test is geometry: two parallel vertical rotary joints plus a vertical linear axis. A four-axis arm with rotary joints and no slide is articulated.

What they are used for

  • Small-part assembly — placing screws, connectors and components onto boards and housings, where arms like the Epson T6-B replace bench work.
  • Pick-and-place and sorting — moving parts between trays, conveyors and fixtures at cycle rates articulated arms cannot match.
  • Dispensing and inspection — moving a nozzle or camera over a flat part, where only X, Y, Z and a twist are needed.
  • Teaching labs — compact units such as the DOBOT M1 Pro introduce industrial programming on a desk.

What to compare

Attribute Why it matters In this catalogue
reach Working radius; the vertical stroke is the other half of the envelope 400 mm (DOBOT M1 Pro) – 600 mm (Epson T6-B All-in-One SCARA Robot)
payload Light by design; a few kilograms is typical 1.5 kg (DOBOT M1 Pro) – 6 kg (Epson T6-B All-in-One SCARA Robot)
repeatability The reason to choose a SCARA; typically tighter than a desktop articulated arm 0.02 mm (DOBOT M1 Pro) – 0.04 mm (Epson T6-B All-in-One SCARA Robot)
axes Four is standard 4 (all 2)
mounting Floor or table; ceiling-mounted versions free the bench table (2)
collaborative Few SCARAs are rated to run unfenced; check the attribute no entries yet

Price picture (observed 2026-10-28)

  • Professional / industrial: GBP 4,614 (DOBOT M1 Pro).
  • On quotation: Epson T6-B All-in-One SCARA Robot.

Prices are the latest observation per product, in the seller's currency; see each record's offers for history and VAT notes.

In the catalogue

Professional / industrial: DOBOT M1 Pro · Epson T6-B All-in-One SCARA Robot

Edge cases

  • Four-axis desktop arms with no vertical slide: articulated, not SCARA.
  • Delta pickers: parallel arms, even though they also do fast planar pick-and-place.
  • A SCARA on a linear track: still a SCARA; the track is an extra axis.
  • Ceiling-mounted SCARAs: still SCARAs; mounting records it.

Related

Arm · Articulated arm · Parallel arm · Cartesian arm · Cylindrical & spherical arm · Vacuum gripper

Rule of membership

Two parallel vertical rotary joints plus a vertical prismatic axis.

Category rb-1-2 in the whatrobot taxonomy.