Choosing Between Robots and Cobots for Robotic Welding

Automation has been a boon to the welding industry, assisting with the skilled-labor shortage and in producing precise and repeatable welds as well as increasing productivity. While the benefits to welding automation seem clear, selecting the right piece of technology may be less so. Selection requires the need to balance purpose, price and how it will propel a manufacturing operation forward. Recognizing key nuances between two welding-automation options, robots and cobots, is essential to attain positive results. 

Robots and cobots, though strikingly similar, each possess unique characteristics that serve specific purposes, making their utility more or less beneficial depending on the circumstances in a particular manufacturing operation. When choosing, keep the following considerations in mind.

Part Throughput

As soon as a fabricator begins experiencing higher part throughput with lower part mix, it will want to explore automation dedicated to that specific part or product family. In such a case, robots offer repetitive, high-precision welds, providing the uniformity needed when producing high-volume parts. Meanwhile, cobots offer flexibility for customized welds, providing the adaptability needed when producing a higher part mix of low-volume runs. Cobots are restricted to relatively low top speeds compared to robots to account for collaboration within the cell, typically resulting in lower productivity than robots.

Workspace Accommodations

Each shop differs from the next, especially concerning available space and how a piece of welding automation can fit. Traditional robots typically install in stationary weld cells to maintain the precise programming required for a workpiece and to achieve repeatability over the course of a run, making a robot a relatively permanent fixture wherever it ends up. From a size and safety perspective, a robot requires more floorspace than a cobot to prevent potentially unsafe human interaction. Robotic welding cells may use light curtains, fencing or locked gating to provide adequate distancing from the moving robots and parts inside of cells, and to ensure that the robots will not operate should humans be present.

Cobots, designed to work alongside humans, can eliminate the added safety need of gates. And, because cobots are smaller, they have the flexibility and adaptability to adhere to changing work requirements. This makes cobots well-suited for tighter workspaces and shops that prefer portability to move automated welding equipment to where the work resides.

Part and Arm Size

Size doesn’t always matter, but when it comes to the capabilities of welding automation, part size directly impacts the ideal length of a robotic arm. Arm length determines whether the welding gun can reach necessary weld joints and maintain the precision required of a weld and the overall finished product. Unsurprisingly, a larger part benefits from a longer arm to ensure coverage across the entire work envelope and to mitigate the need to reorient the automation or part. Depending on robot size, maximum reach can extend from 5 to 10 ft. Robots also can travel automatically via external axes, such as a track setup, to extend  their reach into the cell.