The implementation of highly capable and flexible tools that help scale production as demands change is paramount for a competitive edge within the industrial landscape. Key among this use is the integration of extremely reliable robotic automation. From assembly, dispensing and inspection to picking, palletizing, welding and more, the range of dirty, mundane and unsafe tasks industrial robots can tackle is extensive.
To better address fabricator concerns for more affordable robotic options that can be easily integrated and redeployed on demand, robot suppliers continue to focus on collaborative robot, or cobot, development. In turn, these meticulous efforts are igniting a wave of cobot usage that is expected to occupy 30 percent of the global industrial robot market by 2027.
Cobot advantages
The deployment of extremely agile welding cobots is witnessing a significant increase in utilization. Inherently safe by design, power and force limiting (PFL) cobots can work with or near human workers without additional safety measures – pending a thorough risk assessment of any robotic system – including the application, robot, workpiece, work area and end-of-arm tooling (EOAT). Easily rolled up to large, heavy workpieces or placed beside manual welders for supplemental fabrication, these virtual workhorses aid in creating hyper-productive workspaces.
Offering many of the benefits industrial robots can bring in a convenient package, user-friendly cobots can help overcome tough challenges, especially as labor concerns grow. With a total of 360,000 new welding professionals projected to be needed by 2027, industry experts anticipate that the use of cobots for welding-related tasks will soften the proverbial blow.
Effectively combining the skill of a human welder with the precision and efficiency of robust robotic automation, safe and intuitive cobots help bridge the welding knowledge gap. What once required weeks of training by a human worker is now fulfilled with a welding cobot and intelligent peripheral tools in a matter of hours or days, freeing current workers to complete higher value-added tasks. Moreover, the use of highly flexible cobots enables small to medium-sized enterprises to do more with less, bolstering smaller workforces, aiding tighter budgets and accommodating floorspace restrictions.
Cobot prerequisites
While the equipment used for a particular application is dependent on process requirements and a thorough risk assessment, manufacturers looking to implement cobot welding should be mindful when it comes to cobot selection. Foremost, finding a cobot brand that is built on the same platform as proven industrial welding robots is ideal. For example, Yaskawa industrial robots, such as the AR and GP Series, use Inform programing language or an intuitive “smart” teach pendant via the YRC1000 controller. The same applies to Yaskawa’s HC Series human collaborative (HC) robots. This is extremely helpful for robot users that want to take jobs from one robot type to another.
Along with this, a cobot’s ability to utilize the same essential and powerful welding tools as industrial robots is also beneficial. Where power supplies are concerned, it can be important for customers to be able to use their preferred brand to maintain a single stock of consumables and user knowledge. Likewise, whether it be the use of waveforms to increase safety and quality, through-arc seam tracking to compensate for workpiece or fixture inaccuracies, or through-wire touch sensing to find the orientation of parts with simple joints and geometries, cobots should be compatible with these proven technologies to truly benefit welding operations.
Similarly, cobots with diverse programming options that can scale with production as needed are best. Versatile cobots should cater to various skill levels and programming needs. For example, a standard teach pendant should be available for use to cater to more experienced robot users, where their “muscle memory” and welding expertise can be used to accelerate the robot programming and integration process.
Teaching tools
To enhance application safety and gain greater versatility, especially where EOAT is involved, having the ability to change specific functions from the cobot teach pendant can also be helpful as most welds are not simple, flat, straight lines. Settings for avoidance function, force monitor, speed limit function, external force limit, torque sensor calibration, safety mode security level, safety logic circuit and more should all be adjustable from the teach pendant.
For less-experienced or novice cobot users, highly intuitive teach pendants, like Yaskawa’s’ Smart Pendant, provide improved graphical user interfaces with familiar icon-driven programming. Moreover, patented built-in technologies, such as Smart Frame, make the robot programmer the frame of reference and jog the robot relative to the user, effectively eliminating the need of knowledge for conventional coordinate frames (X, Y, Z) and enabling quick implementation of the robotic system for more basic tasks.
Intelligent pendants like this should also have the ability to switch to a classic view of the user interface, allowing experienced professionals the option to revert to traditional prompts.
Whether using a standard teach pendant or newer smart pendant, the utilization of feature-rich software applications and specialty application modules can enhance the cobot welding process. Intuitive pendant applications and interfaces, such as the Universal Weldcom Interface (UWI), help bridge the weld programming knowledge gap for standard and smart pendants alike, allowing users to gain easy control of any welding process or parameter from the power supply.
Enabling fast adjustments to items such as voltage, amperage and wire feed speed, these processes are matched for welding certain metals that have specific shielding gas requirements (and sometimes proprietary filler metals), ensuring high-quality welds. Features for touch sensing and dual pulse can also be manipulated. Other smart pendant apps, like Weld Builder, allow users to easily set various welding operations specifically for cobot applications. All of this serves to facilitate the trend toward no-code programming and tech-savvy shop floor transformations.
Extremely helpful for quick programming and redeployment on demand is the ability to perform hand-guided teaching. Providing users with the ability to physically grab and guide a robot by the T-flange, this lead-to-teach method simplifies the need for understanding coordinate systems and fosters a quick and easy learning curve. Experienced weld programmers that already understand how to position and travel a weld torch can simply recreate the same movement by hand-guiding the robotic torch. This is especially helpful in high-mix, low-volume settings where frequent changeovers occur.
Keep in mind, for some applications, hand-guiding may make it difficult to adjust tool axes or individual robot axes for access into parts or in tight spaces. Conversely, hand-guiding is often complemented by traditional programming methods to adjust torch angles or facilitate work in close spaces.
Cobot designs
Aside from robust tools and easy programming, cobot designs themselves are extremely important to the welding process. Foremost, cobots should boast an IP67 rating. Designed to work in rough environments to guard against weld spatter or harsh chemicals, IP67-rated cobots feature easy-to-clean surfaces and require no extra protection or “jacket.” Human welders in close proximity, however, should still consider all risk mitigation for the welding application being performed.
Cobots must adhere to safety standards in RIA 15.806. This can include everything from the design of the arm to prevent pinch points or even abrasion injuries to how the robot reacts to its environment and collisions. Anything added to the robot, including the EOAT, must also be assessed with the rest of the robot as to not add any potentially dangerous elements to the cobot and application.
To suit floorspace and application requirements, robot suppliers and integrators continue to develop a range of collaborative solutions. Welding equipment companies and robot manufacturers alike have been introducing new products to this space, many of which are built on the need of the industry they serve.
Extremely portable and space-saving weld carts with minimal features and a single cobot can easily assist the welding of large, heavy workpieces, often eliminating the need for a large, expensive dedicated workcell. Adding flexibility for small to medium-sized part processing, pre-engineered collaborative workcells that are fully equipped with an industrial pedigree cobot, integrated weld package, intuitive weld interface, arc flash protection, fume mitigation and more also help with capacity challenges across the industrial landscape.
While there is no one-size-fits-all solution, the use of cobots, along with robust and intelligent peripherals, will continue to provide shop floor agility to address production challenges for greater operational excellence. Whether to fulfill high-mix, low-volume production demands or address labor shortages or other manufacturing challenges, flexible and efficient cobots with durable designs can optimize operations for future gains.
