Technical progress is creating more possible applications for robots in the industry. What the new developments bring for medical devices is shown in research and by a system integrator. Two experts give their assessment, from Cobot to Social Robot.

You’ve probably come across them, too: Anyone preparing for a visit to the Automatica trade fair cannot avoid terms such as cobots, no-code or low-cost robotics, networking, or even social robots. But how important are these technological approaches in medical technology?

“Cobots (i.e., collaborative robots that work near or with humans) are an area that is currently driving the robotics community,” says Andreas Rothfuss, who develops robotic solutions for medical technology at BEC GmbH in Pfullingen. Cobots are interesting for this industry, Rothfuss adds. “Since it’s always about patients who are in the immediate environment, every robot in medicine has to be a cobot, so to speak.” He says the technology for this is already available, and the first systems are coming onto the market. “However, it will be a while before we see applications in medicine more frequently, as development times are simply longer here.”

First, Industrial Automation, Then Class IIb Medical Device

The automation experts at BEC know both the industrial and medical sides of robotics. Managing Director Matthias Buck founded the company about 18 years ago. The initial focus was on industrial automation and the construction of special systems. BEC continues to work on these and coasters in the entertainment sector. Medical technology projects were added to the agenda in 2011. Today, the company offers a positioning system for patient couches certified as a Class IIb medical device according to MDR. Another product, which can be used to position interventional needles, is being prepared for market launch.

Robots in medical technology have “a lot of potential,” according to Andreas Rothfuss. Currently, a quarter to a third of BEC’s sales are in this sector—and the Pfullingen-based company expects growth in this area. However, he says that not everything that works well for industrial production is ideal for medical devices.

No-Code Robotics: Not So Easy For Medicine

He cites the no-code programming of robots as an example of this. “For industrial applications, including the production of medical devices, such systems are super interesting,” Rothfuss says. Especially in combination with low-cost robots, he says that something like this could also be considered for automation tasks in small and medium-sized companies. “It’s not just the price of the robot that causes automation costs to rise. A large part of it is the robot integration into the system.”

Where tasks change frequently, he says that it is beneficial to set up the robot without any programming knowledge of your own. “For medical devices, I don’t see that happening because it’s the flexibility of the robot that would probably be a problem for approval,” Rothfuss continues. However, he added that use scenarios are conceivable—perhaps not as a medical device, but certainly for logistics and handling in the healthcare sector. “Handing a tray or moving a bed through a hospital would certainly be feasible with simple systems.”

Model-Based Safety Validation for Robots in Medicine

Magnus Hanses, who works on surgical robots at Magdeburg’s Fraunhofer Institute for Factory Operation and Automation (IFF) and heads the Cognitive Robotics Group, takes a somewhat more optimistic view. He emphasizes that in no-code robotics, too, the robot is programmed, “but in a way that enables higher-level instructions—like ‘go there, grab this.’” In medicine, something like this could lead to universal applications for robots. He adds that approval is an important aspect. “A model-based safety validation is currently being developed at the Fraunhofer IFF that could promote such approval,” says Hanses. This method enables dangerous collisions to be evaluated using simulation. A demonstrator will be on display at the Automatica trade show.

He and his colleagues are also concerned with flexibility in robot applications in the operating room as part of the Stimulate research campus. “A robot pays off primarily when it is used frequently – but previous systems were often highly specialized for a single type of procedure that might not be performed often enough to justify an investment,” he explains. Accordingly, he says, hospitals are skeptical when it comes to purchasing an assistant robot.

Robot To Take Over Simple Holding Tasks in Medicine

The solution from the Fraunhofer IFF, which was developed as part of the Stimulate Research Campus, was therefore designed to be more flexible from the start. It is mobile and easily transportable from OR to OR. “We have received feedback from physicians that a robot would be welcome if it manages to replace a person in the OR who only performs simple support tasks,” says Hanses. In addition, an assistant robot should be able to do this in as many variants as possible.

However, we are not talking about no-code robotics here. Instead, the Magdeburg team uses a lightweight robot programmed so that its movements cannot harm people in its immediate vicinity.

Robots Must Be Adapted to The Situation in The Operating Room

In a project lasting several years, the initial goal was to develop an instrument positioning system for a spinal operation in which the robot assists the surgeon. “The precision that can be achieved with a robot is a big part of the benefit here,” Hanses says. There are also plans to test the robot-guided use of an ultrasound probe.

However, even though the robot can potentially work very accurately, it faces special challenges at the operating table. While the workpiece waits at a defined position in production, in the medical environment, the robot encounters the patient, who is at least breathing and could usually move in some other unpredictable way. This means that the planned application field is not always at the expected location—and the engineers must prepare the robot for this.

The solution for this, which the Stimulate research campus is developing and for which the requirements were coordinated with experts from Siemens Healthineers, relies on a marker system. This is fixed through the skin for interventions on the spine and provides the jointed-arm robot with the reference point it needs to guide an instrument to the intervention site planned by the physician. In this way, CT imaging can be greatly reduced and, accordingly, so can radiation exposure for patients and physicians, which is another argument for using a robot in this environment.

Safety in The Operating Room: When Does the Robot Hurt Someone?

Safety is a big issue here because, in the OR, contact with the patient is part of the application. “When we talk about safety in the industrial environment, we refer to ISO standards that define different operating modes for safe operation, such as force and power limitation or speed and distance monitoring,” says Hanses. The goal is for the robot to not move with too much momentum when it gets close to a worker. Biomechanical limit values were defined to achieve this; in other words, the robot must not inflict pain on the human on contact. “What that means exactly was tested in a study with test subjects at the Fraunhofer IFF. On this basis, we want to define what is permissible for robots,” Hanses adds.

In the case of speed and distance calculation, the robot should not even touch the human in its work area but stop beforehand until it comes to a standstill. “Both are much easier to achieve with lightweight robots than with a heavy industrial robot,” says Hanses. The Magdeburg engineers are using the LBR lightweight robot from Augsburg-based Kuka AG, which was developed for industrial applications and their OR project. Its joints are additionally equipped with torque sensors. In addition, they provide the measured values for the robot to proceed sensitively.

For further work, however, a change is planned. “We will use the LBR-Med, which has the documentation for certification according to MDR and meets additional requirements for use in medicine,” Hanses says.

Robots For Medical Technology: Best to Bring a Lot to the Table

The automation experts at BEC also opted for this system—for the same reason. “If I can buy a suitable system,” says Rothfuss. “I save myself a lot of costs and nerves.”

BEC welcomes more projects with medical device manufacturers. These could involve robotic integration into medical devices and the use of robots in the production of the same, he adds. “With its business areas, BEC brings the necessary competencies for both.”

Rothfuss says projects that build directly on the Exacure system developed by BEC for patient positioning or the Guidoo interventional needle positioning system are of particular interest. “A lot could be made of that through adaptation—and especially for the technology behind Guidoo, there’s a broad field of possible further applications.”

Proboscis? Tentacle? That’s Where It Gets Complex

Speaking of further development, could new, bionically inspired robot shapes that resemble trunks or tentacles advance robotics in medicine? On this question, both experts are skeptical. “Such concepts are exciting when it comes to being able to reach certain positions in a confined space,” Rothfuss says. “But controlling something like that is incredibly complex. To implement that and also achieve an advantage over a stable conventional system, I can hardly imagine.” Hanses also believes that the precision expected of the robot would be challenging to achieve with it. “But in the human environment, such systems have an important advantage: there’s no place to get stuck or bruised.”

Interaction with other devices is also essential for robots to have advantages in medical use. This is conceivable by utilizing cables or via mobile communications standards, such as 5G. “For our positioning systems in medicine, we rely on cable-based solutions: They are simpler, run more stably, and have no problems with approval,” says BEC employee Rothfuss. However, he says there are currently many projects related to the use of 5G in medicine. “For example, when it comes to controlling robots in the operating room that a medical professional operates remotely, 5G becomes interesting—or perhaps other standards.”

Mobile Communication Standards for Robots in the Operating Room—If the Latency Is Right

“IT specialists must answer whether 5G offers the required extremely low latency times for this,” adds IFF staff member Magnus Hanses. “For mobile robots, wireless data transfer is interesting in any case because they use rechargeable batteries. This means they only have a limited amount of energy available.” If you don’t want to integrate heavy computing technology, he says that calculations in the cloud are an elegant alternative—even for teleoperations.

But currently, the main issue in Magdeburg is how the physician right next to the operating table controls the assistance system. The Magdeburg team is currently working with a floor that uses sensors to record a person’s weight. This makes it possible to determine the physician’s position and where he or she taps with the tip of his or her foot so that, for example, a button can be projected onto the floor to create a sterile operating option.

Such approaches are interesting for industrial partners, says the group leader. Hanses hopes that the Automatica trade show will bring further contacts of this kind. In any case, the OR system will be on display there at the Fraunhofer IFF booth.

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Source: Announcement medizin&technik dated May 30, 2022