Scara robots have been around for over 35 years but now they are really coming of age. Their robust simplicity has been proven efficient in many industries, notably electronics and assembly, but programming complexity and cost have limited their markets. The recent development of low cost control systems, new hardware designs and new robotic safety features are bringing costs down and making robots easier to work with.
SCARA is an acronym of Selective Compliance Articulated Robot Arm. It is this selective compliance that makes the SCARA design a great starting point for a low cost arm. By having only one Z axis actuator the robot only requires this axis’ motor and gearing to be powerful enough to work against gravity. The rotational axes work only in the horizontal plane and so do not need big motors, high power electronics or expensive gearboxes.
While many current SCARA robots are exceptionally fast and powerful a recent shift in industrial robotics is seeing the growth of lower speed, lower cost robots that open up new industrial applications. An additional benefit of lower power robots is that they will usually be inherently safer.
Scara robots can also be easier to use in many applications as there is not the variety of angles and configurations possible with a more complex, anthropomorphic arm of the type that is very common in industry. As a SCARA robot generally holds its tooling, whatever that may be, in a single direction, orientation is simple and predictable. This has benefits in programming especially when feeding CAD and G-code information to the robot controller as is frequently needed in flexible high technology manufacturing.
Due to the lowering cost of many sensor technologies robots are becoming both safer and easier to use, both in installation and in general production. Robots can also deliver huge amounts of data back to monitoring and control software allowing continuous monitoring, analysis and improvement of processes. The latest safety standards for industrial robotics allow suitably designed and equipped installations to work “cage free” without the need for guarding or human robot segregation. This offers users lower costs, greater flexibility and greater acceptance of robots as just another useful production tool.
The latest examples of SCARA robots hitting the mainstream include robots such as the MakerArm, collaborative dual SCARA robot the duAro from Kawasaki, ABB’s new range of SCARA Robots including the IRB 910SC, the Precise Automation PF400 collaborative SCARA and the exceptionally low cost, but industrial quality Flux Integration Ally robot.
So although humble SCARA robots have been seen as the simple relation to 6 axis industrial robots their simplicity is also their strength in the new world of accessible industrial robotic automation.