SCARA Robots: Guide to The Most Versatile and Sought After Robot

13 September 2021
Selective Compliance Assembly Robot Arm (SCARA robot)
Catherine Bernier
Content Manager
,
Content for Cobot

The SCARA robot is a popular choice for small, high-speed, and high-precision applications. This article explains the basics of SCARA applications and the impact they can have on your business.

SCARA robots are unique robots with a special place in the industrial robot family. You might wonder, what is a SCARA robot? SCARA stands for Selective Compliance Assembly/Articulated Robot Arm. These robots are identified by their big swivel joint and ball screw. SCARAs are smaller industrial robots and have specific applications at which they excel. Their combination of speed, compactness, and precision gives them a special place in the industrial robot lineup. 

This article will introduce SCARA technology to you through the following topics:

Standard Applications for SCARA Robots

Due to their mechanics, SCARA robots have specific use cases. These robots are more of a specialty type compared to general-use articulated arms or six-axis robots. This means SCARAs aren’t suitable for every application. However, they will be an excellent option for the types of applications they are made for. Such applications include: 

  • Assembly
  • Disassembly
  • Pick and place
  • Material handling
  • PCB soldering
  • Dispensing

You can undoubtedly task other robot types for these applications. But what makes a SCARA a good choice over other robots? Small, high-speed applications that don’t require the flexibility of a six-axis robot, for instance, can be a great way to deploy a SCARA. This is especially the case when a high level of precision is required. 

SCARAs mechanical construction is often the primary advantage over other robot types for these kinds of tasks. Selective compliance means its arms can only move freely in specific dimensions. This differs significantly from the general-use six-axis robots that can flex and contort themselves at any angle you can imagine. This may sound like a negative feature, but this selective compliance significantly benefits specific applications. This rigidity allows the robot to have a high level of precision compared to other robot types. Precise mechanics are essential for small, high-speed applications like those listed here. SCARA robots’ strengths and limitations are discussed in detail later in this article. 

Industries for SCARA Robots

SCARA robots have specific use cases, but you will find them in a broad range of industries. Such industries include:

  • Electronics
  • Telecommunications
  • Food and beverage
  • Retail manufacturing
  • Automotive
  • Pharmaceuticals

These industries commonly require the tasks listed in the applications section. They often use smaller components and produce smaller products. Additionally, these industries are high-volume producers. The SCARAs speed helps it to excel here. 

Strengths and Limitations of SCARA Robots

SCARA_industrial_robot

 

SCARA robots are great for specific applications but a bad choice for others. It is essential to understand the strengths and limitations of these robots to make a good investment. Strengths of the SCARA include:

  • Speed
  • Precision
  • Compactness

SCARAs are small, fast, and precise. A significant reason for their precision is their mechanical rigidity. Specifically, their body doesn’t swivel in the up and down directions. This is why SCARAs are commonly deployed in PCB assembly and soldering tasks. Since PCBs are flat, this application doesn’t require a high degree of flexibility of six-axis robots. PCBs are also small and have tiny components. This means precision is of the utmost importance. SCARA robots excel in precision due to their limited number of axes and range of motion. This leads to less error that is inherent in all mechanical systems.

Of course, SCARA robots have their limitations. They are not considered to be general-use robots that can be deployed in most applications. These limitations include:

  • Small range of motion
  • Small payload capacity
  • Selective compliance

It might be confusing that selective compliance is listed here as a weakness. This feature is great for precision. However, for applications that require mechanical flexibility, it is certainly a limitation. For example, consider a welding application for a car frame. This will likely require a robot to weld across and down a joint to make a complete weld. A SCARA would only be able to weld across. Its selective compliance won’t allow it to pivot and rotate with the flexibility required for this task. In this way, selective compliance can hold the SCARA back for some applications. Moreover, they are also smaller robots and aren’t built for heavy payloads. Additionally, they won’t be able to achieve the reach required for some larger tasks. 

When should you use a SCARA?

Now you understand what SCARA robots are, their applications, and their strengths. But when is a SCARA robot right for you? There are a few key factors to take into account when considering a SCARA robot project:

  • Business case
  • Application fit

Business Case

If you are reading this article, you are very likely someone looking to improve manufacturing processes with automation. Robots can make a significant impact in this regard. But, how do you identify which projects will have the most significant value for you? HowToRobot’s potential finder tool helps you identify potential projects and determine their impact on your business.

Once you have identified one or a few areas of improvement using robotics, you must consider if a SCARA is right for the application.

Application Fit

Previously, you learned about the types of applications that SCARA robots are made for. However, many applications can be done by multiple robot types. The question is, when is a SCARA robot the optimal choice. Specific details about the application will determine which robot to use. Our network of independent advisors can help you choose the right solution for your project if you are unsure.
 

How Much Do SCARA Robots Cost?

Cost is a primary concern when looking at the capital project. Most manufacturers have a general sense that robots can be expensive. This is highly dependent on the application and robot type. However, SCARA robots can be less expensive compared to other robot types. SCARAs command a lower cost due to having fewer components like motors and gearboxes. They are also generally smaller robots which often helps on cost. 

Additional cost considerations should be included in your ROI calculation. SCARAs will require integration costs. These costs include things like physical installation, programming, setup, and safety mitigation. Safety equipment is necessary for all industrial robot types. This equipment includes safety fencing, light curtains, safety scanners, emergency stop buttons, etc. There will also be ongoing maintenance schedules required to keep your SCARA performing at optimal levels. These maintenance tasks include greasing, mechanical inspections, and performance tests.

The lower up-front cost of SCARA robots makes them a great choice for entry-level robot users to begin their automation journey.

Visit our RFQ tool to begin receiving quotes on SCARA robots from suppliers.