Work Impossible for Humans to Fulfill

Robots carry out work that would be impossible for humans to do. Robots provide the required quality, precision, speed and traceability which cannot be achieved manually. Please find examples below:

Universal Robots, Denmark - IFR-Partner

New robot lends precision and reliability to the production of hearing aids

July 2013

Hearing device manufacturer Oticon needed a more flexible robot to handle the tiny hearing device components in its production. The company found the ideal solution in the six-axis robot from Danish company Universal Robots.

Employing robots in the production process was not a new concept to Oticon. This manufacturer of hearing aids had been using robot technology for the past 10 years. But, as the minute components became increasingly smaller in order to make the hearing aids more comfortable, the existing two- and three-axis robots used in manufacturing were no longer suitable.

Arne Oddershede, group leader of the maintenance unit at Oticon's test and production center in Thisted, Denmark, explains that the production tasks could not be performed by manual labor either.

"The parts for modern hearing aids are getting smaller and are often only a millimeter in size. We looked for a solution that can suction small parts out of a mold. This was impossible manually. We needed a more flexible solution that would also be economically viable for smaller production runs," says Oddershede.

Flexible robot arm with six rotating axes

Armiga, the systems integration specialist, also based in Thisted, had the right solution for all these requirements. It was in the form of the UR 5, a six-axis articulated robot arm from Danish manufacturer Universal Robots weighing only 40 lbs and with a payload of 11lbs.

"We realized that two- or three-axis robots were not suitable for the job. Lateral and vertical movements were nowhere near sufficient. If for instance a small part is stuck in a mold, it must be possible to tip it out," says Lars Gasberg, Sales Manager at Armiga.

Intuitive user guidance and the precision of the UR robots, were the features that convinced Oticon. Also, rapid advances in medical engineering have resulted in constantly changing production processes and a broader range of hearing aid models that require a flexible robot handling smaller batch sizes.

Suction tool for up to four components

It took just one day to install the robot for its new task in Oticon's molding shop, where the company handles very small components such as wax filters that are barely a millimeter in size. These are fitted to the inside of the hearing device to protect the electronics from wax buildup in the ear.

Mounted firmly to the injection molding machine, the robot can position itself over the mold and suction the plastic elements using a specially designed vacuum system. This is possible due to a suction tool that can accommodate up to four tiny components simultaneously. The UR 5 is programmed to only engage the suction mechanism when the mold is open. Once it has taken the parts, the robot draws away, and the injection molding machine prepares for a new operation. All the components from the same mold are subsequently collected in separate tubes to ensure that they can be traced correctly. The vacuum system also ensures that the sensitive elements are not damaged.

More complex molded components are handled with pneumatic gripping tools. Because of its six axes, the UR 5 is very manoeuvrable and can rotate or tilt the parts in order to lift them quickly out of the mold. The robot works in four- to seven-second cycles depending on the size of the production run and the component.

Hands-on Robots

Arne Oddershede emphasizes the accessibility and logical design of the UR robots. "Since we produce different batch sizes and components when developing new products, it must be possible to easily reprogram the robot. With a traditional robot, this involves a computer and requires specially-trained staff, typically a programmer. But with the UR 5, any member of the technical staff can literally grab the robot and show it the motion sequence using waypoints," he says.

The robot comes with a fitted safety mode that allows staff to work alongside the robot without any additional safety shielding. There is a sensor installed in each joint that notices when the robotic arm requires more force for a given movement than previously calculated, for example when an arm or a foot is in the way. The robot will stop working immediately if a counter pressure of 150 Newton is detected. This safety mode has been certified by the Danish Technological Institute in accordance with the European ISO Standard 10218.

Cost-effective investment

The price of around EUR 22,000 was another persuasive factor in purchasing the robot from Universal Robots.  "The investment paid for itself within a few short months. Also, the operating costs are reasonable, since the robot works in a particularly energy-efficient manner. The UR 5 has met all our requirements," explains Oddershede.

Oticon has now deployed a second robot for the same field of application at its production site in Poland.