Which Robots are Useful for Polishing?

Many robot types are used for polishing applications. This is due to the wide variety of polishing applications out there. Your choice of robot depends heavily on the specific requirements of your application. Reach, payload, and surface geometry are key features to consider when choosing robot. Each type has strengths and weaknesses in these categories. Let’s look briefly at some common robot types and why you might use one over the other.  

Six-Axis

Finding the most-common industrial robot in this list shouldn’t be surprising. Six-axis robots are excellent for polishing applications. This is thanks to their best-in-class dexterity. Six-axis robots have the ability to contort their arms at all angles. This helps immensely in polishing applications when parts feature curves and sides that require finishing. Other robot types can struggle to give you the same level of performance for parts like this. They also feature a great balance of reach and payload capacity for bigger parts and tooling. Collaborative robots are implied to be part of this category for the scope of this article.

Exterior components in the aerospace industry are typically large and have complex geometries thanks for the optimization towards aerodynamics. Polishing tasks here require excellent reach and dexterity. The complicated shapes demand dexterous movement from the arm of the robot. Six-axis robots excel in these types of tasks.

SCARA

The SCARA robot is a great choice for simple polishing applications. The SCARA should certainly be considered when your part only requires polishing on a single, flat surface. All else equal, the SCARA will be a more cost-effective option vs. the six-axis robot when both can perform the task adequately. However, be careful, the SCARA will struggle to polish complex part surfaces where the six-axis would excel. Additionally, SCARAs are limited in reach due to their small frame.

SCARAs are great for polishing tasks like small mirrors and flat metal panels. These parts are small and simple enough geometrically for the SCARA to handle with ease. However, large parts or those with multiple edges or complex shapes become difficult for the SCARA to polish consistently. 

Cylindrical Robots

Cylindrical robots are a less common choice but still useful for certain circumstances. Similar to SCARAs, they can struggle with complex part geometries due to their limited range of motion. However, they are useful for simple polishing tasks on vertical parts. You can consider a polishing task on a car door as an example here. Their ability to extend and retract as well as swivel their arm helps somewhat with complex geometries, but the six-axis will quickly become a better option here. 

How to Integrate a Polishing Robot

Integrating a polishing robot is no small task. There are large considerations to ensure success and optimal performance. Knowing when to automate, how to choose major components, and who to contact for sourcing are key factors to consider. 

When to Automate

As with most automation tasks, some key indicators indicate that automation may be beneficial. Those include things like having a current bottleneck at the finishing stage, requiring more consistent performance, and a need to increase safety around the polishing line. Polishing robots typically produce at a higher rate than human operators. This can speed up the finishing process which can remove the bottleneck. In addition, since robots follow programmed steps, they offer a higher level of consistency than human operators. Finally, if safety is a concern, relocating human operators from a dangerous task like polishing can help to reduce safety incidents.

Selecting your Robot and Tooling

Your choice of robot and tooling are factors that will have the biggest impact on your ability to optimize your polishing task. Referring back to common robot types, there are choices that are better or worse for certain scenarios. Having a complete understanding of your task and its requirements should guide your choice in the selection here. Proper tooling is necessary to ensure a quality part finish. It may be required to consider a custom option here. Suppliers and integrators are a good choice to start here.

Who to Contact for Purchase and Integration

Knowing who to reach out to for part sourcing can be daunting for some. There are so many suppliers and service providers, but who is best based on your situation? HowToRobot has a large database of suppliers you can connect with. You can request quotes and connect with regional and international providers here. 

Common Challenges with Polishing

Consistent Finish

Finding a consistent finish is likely the single most important goal for automating your polishing task. Some factors can affect your ability to achieve a consistent finish. Level of defect, proper maintenance, and consistent part presentation are key for ensuring optimal performance here. 

Large defects from a polishing perspective like chips and small burrs can be problematic for polishing. Force and torque sensors can be helpful here, but if the issue is too extreme it would be wise to integrate a grinding step beforehand. 

It’s critical to maintain proper maintenance of your tooling for consistency. Maintaining a schedule for tool change-outs and robot maintenance will help keep finish consistency high. The frequency of tool change-outs are specific to your parts and tooling. Manufacturer recommendations are a good place to start.

Part presentation helps make sure your robot is polishing your part correctly each time. Unless your robot has a way to identify part location, you need to present your part in the same way each time. 

Finding the Proper Tooling

Proper tooling can be a challenge. Pre-fabricated end-of-arm tooling for polishing might offer more limited options than desired. It is common to create custom tooling such that the right polish head is used for the job. It is important to connect with the right supplier that can provide custom tooling options.

Part Handling

Part presentation and part handling can go hand-in-hand. Many manufacturers use custom jigs and mounts to ensure parts are held in a firm and consistent manner. The force of your polishing task as well as the size and weight of your parts can guide your direction here. 

HowToRobot is your guide for your automation journey. If you are looking for support with starting to look for automation solutions, we can help you get started.