Once guardians of large- and heavy-part handling, robots are now involved in moving the smallest and most delicate of parts with dexterity. Vision technology advances have led to robots being able to pick and place randomly located parts. From three-dimensional bin picking to food-grade applications, robotics are moving into new manufacturing frontiers.
The use of material-handling robots has increasingly become a solution to raise productivity and manufacturing versatility, while enhancing worker safety as they historically have. Material handling is a natural extension of robotics and an area where the technology has already been predominant for many years, but robots are finding new applications.
Safety has been one of the most important hallmarks of materials handling in manufacturing and production environments. For workers, the job of lifting heavy and awkwardly sized containers in addition to operating material-handling equipment like forklifts can be hazardous in itself. Robotics came into their own when there were requirements to work in hostile and potentially unsafe environments.
The use of robots cut down on injuries, ranging from strains and sprains from lifting loads incorrectly or handling overly large or heavy loads, to fractures and bruises from being struck by materials or caught in pinch points, to cuts and bruises caused by falling materials that were improperly stored or unfastened.
As technology advances, however, manufacturers are increasingly using different types of machines to safely move, store, and retrieve all types of materials. More and more, robots are being called upon to move and store materials ranging from products as small as vials of liquids to as big as cars in manufacturing processes.
Manufacturers have had to adapt to consumer demands for more sophisticated products and faster availability of goods, resulting in greater capital investments in robotics to become more efficient. With robotics, quick turnarounds from one product to another are readily being carried out, with the ability to move larger variations of products and adjust to productivity demands.
The technical challenges are to be more versatile, and the key is to better and more efficiently handle products. For small items it is the ability to have more dexterity when picking up and putting down products, while moving big products requires larger grippers with arms that can carry heavier weights.
In addition, the variation in the types of packaging that must be handled creates another set of issues. To improve these abilities, progress in vision, software, and gripper technologies for robotic handling of extreme parts -- ultra large and heavy ones to small and delicate components -- is being forged ahead.
For small and fragile parts such as electronic components, glass panels, and even food products, robots that are quick but precise enough to meet production needs and not cause damage are required. Delta-style robots might be the manufacturers' manipulator of choice for these types of applications. When it comes to tiny or delicate products, manufacturers often use 1-kg payload delta robots.
Food-handling challenges when handling raw food are complex, but there are grippers certified by the U.S. Department of Agriculture (USDA) that can touch food directly. Biotechnology applications are another area where robots and grippers that are certified by the Food and Drug Administration (FDA) are useful, as they can handle vaporized hydrogen peroxide cleaning after handling blood and plasma samples.
As robotic capabilities expand, they have become faster and can carry heavier loads. In the past a robot required a heavy-duty manipulator, and as parts got larger, grippers have become also become larger. There is a trend toward robots that can pick up payloads as large as 3,000 pounds. Usually, this challenge is managing the synchronization of two or more robots. Advanced technology using a single robot is a possible solution that reduces workspace area and lowers the complexity of the material-handling operation.
Robot manufacturers are constantly trying to find more efficient ways to move parts. Area scanners provide a potential solution for three-dimensional bin-picking. Scanners use a controlled light pattern to build an array of points to guide the robots. Bin-picking tasks can be carried out in less time and without sensor heads on the robot.
A vision-guided robot could be used to pick and load trays of products into bags. As many as three different products could be picked and placed using vision to locate the products and determine their orientation. The robot takes products that are randomly oriented, loading the trays and then unloading them, followed by repeating the process.
As we move further into the future, robotic handling of more and more sizes and types of products will be carried out more efficiently and cost effectively. Material handling is one of the predominant areas where robotics will continue to play a major role. Upon faster speeds plus tooling and software improvements, material-handling robotics have improved rapidly in the last five years, and this trend will continue as technology advances.
Photo credit: Robotiq
Bob Clark is vice president of sales and marketing for Bishamon Industries Corp., based in Ontario, Calif. Bishamon is a manufacturer of lift tables, pallet positioners, skid lifts, pallet trucks, and other handling equipment. The company's products are designed to enhance ergonomics and worker safety and productivity. For more, visit www.bishamon.com.