Colleague robot,
please take over!

So far, robots and humans have rarely worked side by side. Common robots are mostly stubborn recipients of orders that blindly perform programmed movements and are hardly able to respond to unexpected changes in their environment. However, manufacture of products in small numbers and quickly changing market requirements need flexible and intelligent robot systems that can autonomously adapt to current requirements and the environment while being capable of interacting with humans intuitively and safely at the same time. Innovative hardware and control concepts as well as methods of artificial intelligence will enable that in the future. At DLR, a variety of new technologies and methods are being developed to enable flexible and adaptable future production.

How does human-robot collaboration (HRC) go smoothly? How can mobile robots autonomously take over “handicraft“ tasks, assemble products, or cooperate with 3D printers? Is it possible to plan ahead the real use of robots by means of simulation, and can they be digitally controlled? In the project “Factory of the Future”, ten DLR institutes are jointly working on these issues to develop trend-setting technologies.

DLR’s lightweight robot technology plays a central role in this respect. It constituted one of the greatest revolutions in recent industrial history. Cobots, new sensitive lightweight robots such as LWR iiwa from KUKA AG master complex hand movements and show consideration for human colleagues – thanks to sensors in their joints capable of recognising physical contacts. In case of collision with a human, the robot stops or backs off, and sensors in the “fingers“ enable tactile identification as well as soft gripping of tools, workpieces or even fruits and vegetables prone to dents.

The benefit: a robot like the LWR iiwa can perform non-ergonomic activities as a henchman, for example overhead work or handing over of parts. Since 2009, a prototype version has been used at Mercedes-Benz in the first series deployment worldwide. The technology that has initially emerged from space flight has been developed by the German Aerospace Center (DLR) for use in industry since 2004. DLR researchers are working in close cooperation with their colleagues from KUKA and Daimler. Today, many more automotive manufacturers such as Volkswagen, BMW, and Ford use this technology to relieve humans in their daily work.

The lightweight robot at Mercedes-Benz inserts crown wheels and bearing shells weighing 5‒15 kilogrammes into gear casings.
© KUKA Roboter GmbH

The LWR iiwa lightweight robot in collaborative assembly of a front axle gear at the BMW works in Dingolfing. Ergonomics for the employees can be significantly improved by the assistance of the robot arm as heavy components are positioned by the robot with millimetre precision.

The latest generation of lightweight robots is the robot arm SARA (“Safe Autonomous Robotic Assistant“), developed at the DLR Institute of Robotics and Mechatronics. The highlight: thanks to innovative electronics, sensor technology, and mechanics, SARA can be hand-trained for highly diverse tasks by recording both the position and the forces acting on the robot arm. The operator not only imparts to the robot what to do, but also how it can tackle a task. The video demonstrates how SARA is shown the complex assembly of an aircraft window and autonomously implements what it has learned.

While there is an ever-increasing number of robot types available for “human-robot collaboration” (HRC), sharp-edged robot tools and workpieces still present a major challenge. To solve this problem, DLR has developed an airbag enabling HRC – without a protective fence – for a broad range of robot tools and workpieces without restricting the function of the overall robotic system. To this end, the airbag encompasses the tool and the workpiece before the robot approaches them, and subsequently releases them. In this way, cycle times in manufacture can be reduced and productivity is significantly enhanced.

Even the idea of an indoor crane is revolutionised with new robots: in DLR’s SwarmRail concept, robots are running on their own tracks underneath the hall ceiling. Instead of standing or running on the ground, they become space-saving “high flyers“ performing manifold transport or assembly tasks from above with their robot arms. In this way, the available space in the hall is optimally used and production processes are speeded up.

The sensitive harvest and storage helper: the DLR hand CLASH (Compliant Low-cost Antagonistic Servo Hand) from 2018 can grab fruits and vegetables in a soft manner so that, for instance, a mango will not get dents. Particularly interesting: the hand is relatively cost-effective.

An interesting idea of Rinspeed AG from Switzerland: a robot arm replaces the steering column in the concept vehicle named Budii. In this way, the steering wheel can be moved from the driver to the front-seat passenger or hide away when the car is driving autonomously in a traffic jam.

However, robot arms and hands are not only interesting for the industry. They can also “cure” the incurable – or just be fun.

DLR’s HIT Hand II has five fingers and is almost as large as a human hand. A robot, here Justin from DLR, can use tools designed for humans – like this cordless screwdriver. This robot hand, the most highly developed one in the world, is marketed by the DLR spin-off Wessling Robotics GmbH.

Autonomously enjoying a cup of coffee despite paraplegia? This 58-year-old female is completely paralysed from the neck down due to a stroke she suffered 15 years ago. Within the scope of a study with a robot arm controlled by neuronal stimuli, thanks to this aid she was able to “grab” a bottle with coffee, “raise” it to her mouth, and drink with a straw after only a quarter of an hour of “training”. For control purposes, the neuro-prosthesis BrainGate2 was implanted in the motor cortex of the brain. A wireless connection is not yet possible – however, researchers are working on it.

Recapacitating robotics offers care-dependent persons and people with disabilities effective support in their daily lives. The mobile robot EDAN, developed by DLR, is a combination of an electrically operated wheelchair and robot arm. It is controlled by muscular signals. Paralysed persons obtain autonomy and quality of life through robotics, from opening a door to drinking from a glass. In addition, the robot arm is not just a recipient of orders but features built-in intelligence. It is capable of recognising intentions and knows how to respond.

Initially developed and verified to be used by astronauts in space, robotic technology is also used in medical technology thanks to DLR researchers. Surgeons are doing a great job, but it often gets very tricky when it comes to the very small range. DLR’s MIRO is a robot arm capable of assisting the surgeon directly at the operating table. Thanks to MIRO, a greater number of complex surgeries can be performed minimally invasive, for instance, through small skin incisions. MIRO is also capable of sensitively palpating tissue and cutting it by water jet in such a manner that vessels and nerves are preserved. At the same time, MIRO guides a camera to give the surgeon a complete overview at any time. The licence for MIRO was sold to the American company Medtronic. The largest medical technology company worldwide further developed the technologies of the DLR system for a medical robot to make it suitable for use in the operating room.
Moreover, the Europe-wide network Digital Innovation Hub Healthcare Robotics (DIH-HERO) is fostering the further technology transfer into practice.

Due to its humanoid shape, the service robot Justin is well-suited to act in the direct environment of humans. At present, it is prepared to be used as a household help and an assistant for astronauts in space. It is already capable of performing different tasks without human support and can be used as a remote-controlled avatar.
In 2019, Justin assisted ESA astronaut Alexander Gerst in inspection and maintenance of a future solar plant. What was so special about it: Gerst commanded Justin from the International Space Station. In the experiment, Gerst and Justin showed that the cooperation of astronauts in orbit with intelligent robots on the planet’s surface is also ideally suited for future Moon and Mars expeditions.

The humanoid robot TORO is additionally equipped with legs and smart abilities. Thus, it can take over jobs intended for two-legged and two-handed workers – for example, as shown here, in aircraft assembly.

Today, robots often “see“ with their hands, which means by their tactile sense. And what about the eyes? The first sensor worldwide enabling the robot’s 3D sight and spatial orientation comes from Germany, from the DLR spin-off Roboception GmbH: rc_visard enables robots to move in a room, recognise objects and see whether a task was successfully completed – like loading a pallet, counting of objects, and doing everything for what humans use their eyes.

Lightweight robots (LWR) – the very beginnings

Finally, the breakthrough for use on Earth was the LWR III with a payload of 14 kilogrammes and a weight of 14 kilogrammes. That means stronger motors, even better sensors, and stronger joints. And all that without additional weight. The icing on the cake: an appealing, organic design featuring excellent function at the same time: no corners, no rims, no spaces – and thus no danger for the “human colleagues” to pinch their fingers.

No arm without a hand: the DLR Hand

What is the benefit of an arm with no hand at its end? This also applies to robots. Up to now, robot hands in industrial use are rather grippers, special constructions that are optimised for a single, very special task. In comparison, a human hand is much more versatile. It is extremely complicated to rebuild it; however, it is being accomplished with increasing success. DLR scientists take a leading role in the manufacture of artificial hands.

In 1998, the DLR Hand I was introduced, a 4-finger hand with 12 or 13 degrees of freedom (compared to 22 degrees and one additional finger on the human hand).

The DLR Hand I with approx. 1,000 mechanical und 1,500 electric components was considered the most complex of all robot hands built so far worldwide. Each degree of freedom is, so-to-speak, a joint. This meant: 12 drives were required. Nonetheless: the scientists succeeded for the first time in integrating all 12 drives into the hand.

The DLR Hand II, first introduced at the end of 2000, was a further development with better electronics: instead of 400 cables towards the “outside world”, now only 12 came out of the hand.

The DLR HIT Hand II from 2007 is more lightweight although it has now 5 instead of 4 fingers. With 15 degrees of freedom, it is very flexible. It serves as the hand of Space Justin.

The DLR Spacehand (2020) is celestially good: it is so robust that it can be used in continuous operation in space. Maybe someday it will manufacture bricklayer robots for housebuilding on the Moon? Or service robots for spaceships?

Colleague robot, please take over!

Lightweight robots (LWR) – the very beginnings

No arm without a hand: the DLR Hand

Colleague robot,
please take over!