How Good are Cobots at Welding?

The manufacturing industry has been using robots widely for several years as a replacement for the human laborer. Recent advances in this field are the Cobots or collaborative robots. They are called collaborative as their design makes them work alongside an individual as a part of a team rather than replacing the humans.

Cobots are good at operations and activities that cannot be fully automated. However, the process speed does not improve for activities such as workers ferrying parts backwards and forwards between themselves on the assembly line with the robots locked away in cages.

Manufacturers such as Ford are already on the cobot bandwagon, and the new robots could transform the way the industry works. The Ford factory has collaborative robots installing shock absorbers on vehicles on the production line along with humans. The cobots work with accuracy and precision, boosting the human productivity, while saving them valuable time and money.

At present, the industry uses four main types of cobots. They are the Safety Monitored Stop, Speed and Separation Monitoring, Hand Guiding, and Power and Force Limiting.

The Safety Monitored Stop is a collaborative feature used when the cobot works on its own, but sometimes needing assistance from an operator. For instance, in an automated assembly process, the worker may need to step in and perform an operation on a part that the cobot is holding. As soon as the cobot senses the presence of the human within its workspace, it will cease all motion until the worker leaves the predetermined safety zone. The cobot resumes its activities only after receiving a signal from its operator.

Speed and Separation Monitoring is similar to the Safety Monitored Stop, with the cobot operating in a predetermined safety zone. However, this cobot’s reaction to humans is different. The Cobot will not automatically stop because of the human presence, but will slow down until its vision detection system informs it of the location of the person or object. The Cobot stops only if the person is within a predetermined area, and waits for the proximity to increase before resuming its operations. This cobot is useful in areas with several workers are present, at it requires far fewer human interventions.

Although a Hand Guiding cobot works just as a regular industrial robot does, it has additional pressure sensors on its arm device. The operator can therefore teach the cobot to hold an object hard enough and to move it fast enough without damaging the object, while securely working with it. Production lines that handle delicate components find Hand Guide cobots very useful for careful assembly.

Power and Force Limiting cobots are among the most worker-friendly machines. They can sense unnatural forces in their path, such as humans or similar objects. Their joints are programmed to stop all movement at such encounters, and even reverse the movement.

As many skilled workers retire, and replacements are rare, the American Welding Society is working with Universal Robots, to produce a new attachment to their UR+ line of cobots with welding capabilities. The robot moves along the start and stop path of the desired weld, and welds only the specified stitch areas.