Coffee With Robots? You Might Have a New Barista in the Future

Not over a coffee at his favorite Italian restaurant, but while watching the Sunday crime series at home in Pfinztal, Michael Stille came up with the idea of an application that baristas all over the world would fear. Because in the crime thriller "Animals of the Big City", a coffee robot, which initially comes under suspicion of murder, plays one of the leading roles. Impressed by this talented and innovative robot, Stille went straight to work. His aim was to create an efficient robot solution that could serve freshly prepared coffee specialties to customers in record time—and always in a friendly manner and without a break. And the Baden-based tinkerer already had a name for the project: MyAppCafé was to be the name of the new wonder machine. "This would solve all the personnel problems in the catering trade. After all, finding good staff is becoming increasingly difficult at the moment," says Michael Stille. He knows this from his own experience because he has been running a catering business in nearby Karlsruhe for 20 years.

In order to realize such a high-tech project, it was clear to Stille from a very early stage that he would not be able to do it on his own, but would have to bring on board other experts to build his coffee robot. In addition to his business partners, Dirk G. Rothweiler in particular was an important advisor and a helping hand for the young company. He is the full-time manager of a prototype construction company of the same name and works part-time as a start-up scene supervisor for the city of Karlsruhe. With his know-how, he brings together the various trades necessary for such projects. In this case, in addition to a coffee machine manufacturer, professionals for app and robot programming, plant engineers, and a handling specialist were in demand.

Support From the Region

IBS Ingenieurbüro Dr. Klaus Schnürer GmbH (IBS) from the neighboring city of Karlsruhe was commissioned with the project implementation of the MyAppCafé, which mainly consists of a robot cell in which various devices such as a coffee machine, printer, robot, etc. are installed. "IBS implements the ideas of its customers—from the construction of individual mechanical components to the realization of complete machines and plants. The IBS engineers, technicians, draughtsmen, and product designers draw on many years of experience in the field of engineering and project management," explains Marcel Trapp, project manager at IBS. In this specific case, the first step was to work out the idea and preliminary work of the customer MyAppCafé and develop it further together. In the further course of the project, a CAD model was then created in order to place all the required components precisely and check their accessibility by the robot.

A Project With Great Challenges

The requirements for handling the coffee robot were high. Because the solution had to be almost 100% automated. The entire order processing was automated, from order acceptance, brewing the coffee, printing a picture on the coffee, to dispensing and cashless payment for the drink. A high level of process reliability was of enormous importance since no operating personnel for the coffee robot will be on site. One of the biggest challenges was to handle the four different coffee cup sizes with a single gripper and pair of gripper jaws, while still using the most affordable (low-cost) digital gripper possible despite the strict budget constraints. Another sticking point was the fact that the cups are stacked rotated in cup dispensers in the robot cell. In order to remove them, a resistance in the form of a rubber ring on the cup edge had to be overcome. Consequently, gripping could only be achieved by frictional connection. A suitable gripper and matching gripper fingers had to be found. Furthermore, the position and the gripping force had to be determined so precisely that the gripper fingers would not slip through the cup, but also that they would not grip too tightly, as there would then be a risk that two or more cups could be gripped at once. For these and other tricky questions, IBS sought the advice of an acknowledged specialist in the field of handling technology—the Zimmer Group.

Product "Made in Ländle"

The gripper manufacturer comes from Rheinau, Germany, and therefore, also from the region. Thus, the coffee robot developed into a real product "made in Ländle" (note: Ländle here refers lovingly to the German region Baden-Württemberg). The expertise of the Zimmer Group has now helped to push the project forward. After an analysis, consultation, and final tests, the ideal gripper was finally found.

The choice fell on the GEP2013IO-00-A—an electric 2-jaw parallel gripper from the GEP2000 series. In addition to a large stroke in a small installation space, it has the possibility to regulate the required gripping forces over four levels. With this solution, as mentioned above, the gripper would, for example, no longer grip too tightly and would no longer grip several cups at once. Another major advantage of the electric gripper is that it can be controlled very easily like a valve via I/O ports. After selecting the suitable gripper, IBS then developed the appropriate gripper jaws. After these had been manufactured in a 3D printing process and extensively tested in several internal test and validation loops, an output unit was developed, dedicated software was written for the communication and control of all components involved, and finally, the robot was programmed.