With the rise of Covid-19 exposing weaknesses in the global supply chain, it has become apparent that many manufacturers need to shift their focus toward scalable factory automation to maintain flexible and efficient operations. Companies relying on human labor have been required to slow or stop production altogether due to physical distancing requirements. Others utilizing fixed or hard automation have found it difficult to adapt to changing demands and product requirements from a volatile market.
Fortunately, there is a solution. Robotic automation can help alleviate these issues, enabling companies to maintain productivity and gain greater agility for “the new now.”
Automation basics
Prior to many of the technological advancements available now, automated assembly lines were designed from the ground up and often customized around a single product or specific task. While many of these lines are still in use and effective for high-throughput operations with no variation, this type of automation can be costly when manufacturing and product requirements change. From custom tooling and fixturing to additional floorspace and changeover time, a lot is required to modify, implement and program a system of this nature.
A derivative of hard automation, but with more built-in flexibility, soft automation traditionally has been a good solution for those who know how their needs will change in the future or for those looking to run multiple batches of similar products. Frequently referred to as programmable automation, this form is often computer controlled and has some mechanical adjustments to deal with changes in production. However, this type of automation can also be time consuming to reprogram and allows for limited variation before modifications are required.
As the recent pandemic has exposed, many industries that could not cope with variation were ground to a halt while smaller, more flexible job shops, integrators and OEMs maintained or altered production to tackle the surge in general-use products. For these manufacturers, another type of automation called “flexible automation” made all the difference, allowing them to quickly adjust to operations and redeploy equipment.
Designed to change with variations in production, flexible automation usually involves a programmable robotic arm with an off-the-shelf or custom end-of-arm tooling (EOAT) with supporting peripheral technologies. Known as the “holy grail” of automation, flexible automation offers the advantage of effective fast and frequent changeovers and being easily adaptable to rapidly changing customer demands and production volumes.
Flexible assets
While the idea of flexible automation is nothing new, a growing number of manufacturers are now realizing the advantages it can bring to the production floor. Whether a completely new system has been implemented or a robotic solution has been integrated with existing hard or soft automation, key components of flexible automation help manufacturers reap multiple benefits.
Versatile industrial robots: Greater accessibility to more affordable, precise, compact and agile robots that are easily integrated, programmed and retaught is a key driver for many manufacturers making the shift to robotic automation. Furthermore, the flexibility robots provide allows manufacturers to optimize workflow and increase capacity for a variety of products. Increased axis speeds, improved acceleration/deceleration control, and optimizations in robot reach and payload also contribute to greater performance capability.
Yaskawa’s newer GP-series family of robots is a good example of robotic ingenuity that facilitates easy installation, operation and maintenance. These extremely fast and highly reliable compact robot models enable shorter cycle times, less downtime and better space utilization. This enables them to fit into existing lines with minimal modification and downtime.
A recent implementation by a leading appliance manufacturer highlights this benefit. Multiple GP-series robots were installed to replace dull, repetitive tasks, enhancing human worker safety while increasing throughput. Due to production requirements, the integration was performed in such a way that existing lines were able to maintain production while the robots were installed in roughly the same workspace as previous human workers. This allowed the integration to take place seamlessly with minimal disruption in productivity.
Feature-rich robot controllers: Another advantage for manufacturers looking into robotic automation is the fact that industrial robot controllers offer a host of unique, built-in features. For GP-series robots powered by the compact YRC1000 controller – in addition to advanced path planning algorithms and robust teaching tools – integrated safety technologies, such as machine and functional safety, allow a robot to be quickly and affordably integrated into existing lines while ensuring human workers remain unharmed.
Advanced functional safety features allow users to create “safe zones” where the robot can operate and define “no-go” areas where obstacles exist. Additionally, Functional Safety Unit (FSU) technology interfaces with other safety-rated devices like laser scanners and light curtains to slow or halt the robot when necessary and automatically resume operation when it is safe to do so.
Another helpful feature for integration is multiple robot control where two or more robots can be run from the same controller and taught using the same teach pendant. This configuration prevents crashes and runaway conditions by constantly monitoring the position of each robot to ensure they cannot interfere with each other or their surroundings.
Collaborative robot (cobot) modes: Over the past several months, both standard industrial robots and cobots have helped manufacturers effectively optimize operations that can successfully manage and fulfill the uptick in consumer product variety. Much of this flexibility is the product of the following cobot modes, which enable robots to operate safely near human workers.
- Safety monitored stop (stop-state): Compatible with all robots that are equipped with an FSU, this mode is popular for re-stocking piece parts and for occasional human-robot interaction. Often utilized with a standard industrial robot (paired with a series of photoelectric presence sensors or a laser scanner), safety monitored stop mode detects human entrance into the monitored workspace, briefly pausing the robot movement until the person is clear.
- Speed and separation monitoring: Used in conjunction with Power and Force Limiting (PFL) robots to increase cycle times or on standard industrial robots to streamline human-robot interaction, this mode is primarily used for optimizing traditional robot applications, such as loading jigs or removing finished parts.
With the help of the controller’s FSU, speed and separation monitoring employs the use of laser scanners, light curtains or vision systems to detect how close a human is to the robot’s work area. When the person enters a predefined safety-monitored zone, a cobot with PFL slows to a safe, collaborative speed where a standard industrial robot slows and then comes to a complete stop as the human worker approaches the robot.
- PFL: The only robots that are inherently safe by design, PFL models are used when frequent human-robot interaction is required. PFL can be combined with other collaborative modes to improve cycle time and worker safety. Ideal for light assembly, machine tending, and picking and packing tasks, dual-channel torque sensors in all joints constantly monitor force to quickly react to contact and halt motion.
- Hand guiding: Paired with PFL technology, hand guiding is a unique feature that simplifies robot teaching by enabling a robot programmer to teach a program path to a robot by physically guiding the robot from point to point. This feature is enabled by the same built-in PFL sensors that also make the robot safe to work with a human worker.
While technically any of the modes mentioned qualify a robot as being collaborative, the entire robotic system must be assessed to determine whether an application is truly collaborative. This includes the robot, the EOAT, the workpiece and the robot work area. Accounting for intended and foreseeable human contact with the robotic system while the robot is in motion is of the utmost importance. If any one of these critical areas fails to meet the standards for collaborative operation, then the application cannot be deemed collaborative – even if a “collaborative” robot, in name, is being used.
Innovative moves
In further regard to cobots, palletizing has become a common use, as the application is repetitive and can be strenuous for human workers. A cobot can be deployed with minimal guarding (as dictated by the risk assessment) at the end of the line, stacking products onto shipping pallets. When the pallet is full, a human worker can remove and exchange it for an empty one. This enables one human worker to potentially manage multiple palletizing stations, greatly improving efficiency.
Many applications once thought to be a deal-breaker for robotic automation can now be met head-on by feature-rich software packages and reliable vision tools. From 3-D simulation and offline programming for optimizing robot and equipment placement to cost-effective and easy-to-integrate vision systems for fast and easy recognition of parts for packaging, palletizing, assembly, machine loading and more, options abound for creating more flexible and efficient operations. Comprehensive software for generating pallet patterns for virtually any mix of SKUs as well as software for conveyor tracking up to 60 m per min. are other popular options for manufacturers looking to increase productivity without adding complexity.
A leading production inefficiency before the pandemic, the quest for finding skilled talent continues to be an issue. However, the combination of smart methods with human-robot process automation has helped to alleviate disruption to some extent, fueling confidence in the benefits that innovative technology can provide.
The use of ergonomically designed, intuitive teach pendants with graphical user interfaces, for example, is making it easier on manufacturers to train individuals with little or no automation experience. Whether it is through a “click and program” approach using touchscreen buttons or through built-in Smart Frame technology that eliminates the use of coordinate frames and enables a robot to adapt to the user’s position, today’s teach pendant technology is helping to provide a fast, simple learning curve to novice robot users.
These innovations, mixed with other technologies such as feature-rich digital weld interfaces, easy-to-program cobots and more continue to facilitate quick implementation of a robotic system.
From high-speed changeover and workforce supplementation to better ergonomics, robotic automation has the potential to help manufacturers of any industry or size deal with the on-going pandemic disruption. When implemented and managed well, flexible robots and easy-to-use technologies can complement human worker talent, creating safer, highly efficient operations that can adapt quickly to change.
Whether it is by incremental upgrades to an existing system or through a completely new installation, companies that embrace robotic automation will increase process flexibility. And, in the end, they’ll be better prepared for the volatile demands of today’s market.
