Customized drinks at the touch of a button
Customized drinks at the touch of a button - what sounds like a dream of the future is already a reality at the University of Stuttgart.
The innovative MADRID dispensing system is not only the result of creative engineering work, but also a key challenge: precise production with high material requirements.
This is precisely where high-performance tools such as RUKO's solutions come into play.
Automatic dispensing system: MADRID at a glance
Students from the Mechanical Engineering & Co. department at the University of Stuttgart have been developing the MADRID dispensing system since 2018. The automated dispensing system makes it possible to mix drinks individually and in seconds - an approach that opens up new possibilities both in the event sector and in the catering industry.
MADRID is an acronym and stands for “Maschinenbaufest DRink Infill Device”. At events such as weddings, company parties and the annual trade group party - the Maschinenbaufest - the system mixes drinks for each guest from a total of 18 different ingredients within a few seconds and is completely mobile. The findings from each event are incorporated into the ongoing development of the dispensing system in order to reduce the effort involved in setting up, dismantling and washing up and to make configuring the drinks as intuitive as possible for guests.
How MADRID works
There are 18 glass containers on the upper level of the cylindrical machine, which were produced in collaboration with the glass-blowing workshop of the Institute of Inorganic Chemistry at the University of Stuttgart. They each hold 1.8 liters of liquid and are filled manually from above during the event.
Silicone hoses guide the liquids from the containers to the lower part of the machine. There are no solenoid valves or pumps here, as their cleanability or delivery speed was identified as insufficient. Instead, the silicone hoses are kinked using servomotors and a lever mechanism.
Dosing during the dispensing process takes place by opening and closing the kinked sections. This means that the liquids only come into contact with glass containers and silicone tubes and are then channelled directly into the glass. The system thus reduces the amount of cleaning required before and after each event and minimises dispensing errors - a clear advantage in event operations.
The system thus demonstrates how drinks can be mixed individually and automatically - quickly, precisely and completely automatically.
For event organisers this means:
- less labor costs
- faster processes
- consistent quality
- an interactive experience for the guests
Mix drinks individually using the web configurator
A QR code takes guests to the configuration website. Here they can select their preferred language and then compose a drink according to their wishes. For events with alcoholic ingredients, the organiser can specify a corresponding limit per drink. Alternatively, a pre-defined drink can be selected from a list and varied in the configurator if required.
The guest then receives a four-digit code with which they can order the drink from the bar staff. This code always remains the same for the corresponding drink so that the same drink can be ordered again later in the evening (even by other guests).
After cashing up, the bar staff send the drink to MADRID and prepare a glass with ice cubes. A sensor on the base plate of the machine recognizes whether the glass has been fully inserted. The dispensing process then begins at the touch of a button. Depending on the number of ingredients contained in the drink, more or fewer of the hose kink valves open at the same time and close one after the other depending on the dispensing time.
Level measurement in the automated dispensing system
As the dosing system works without pumps and depends on the gravitational pressure of the liquids in the higher glass containers, the fill level in each container must be measured. Ultrasonic sensors are used for this purpose, which measure the distance to the liquid surface through two holes in the container lids. In addition, LEDs above the lids warn when the fill level is low and make refilling easier for the bar staff.
Cleaning effort and MADRID V2
MADRID has been delighting guests for years and, in addition to its function as an eye-catcher, transforms the individual ordering process into a fun challenge. At the same time, it presents the set-up, dismantling and cleaning team with the tedious task of laboriously packing the machine for transport and cleaning it extensively before and after each event.
After analysing past events in detail, a new development of the mechanical components was initiated in 2025. Firstly, the glass containers will no longer be permanently attached to MADRID. This means they can be stored separately and protected in crates for transport and cleaned in a dishwasher. Furthermore, an alternative principle will be used to measure the fill levels. As a result, the original, cable-connected container lids with their difficult-to-clean areas can be replaced by simpler lids. However, these design adaptations also required particularly precise machining of new components - especially for challenging materials.
Precise countersinking processes in HPL: countersinks from RUKO in use
Precise machining and countersinking of the holes in particular showed how crucial it is to choose the right tool.
The new base plate under the glass containers was milled from a solid core board (Fundermax Compact Interior 10mm). The material was chosen for its easy-to-clean coating and low warpage - even in occasional contact with liquids.
It soon became clear during the milling process that the material is extremely hard and challenging to machine. Conventional countersinking tools immediately reached their limits for the subsequent countersinking operations.
The solution: the use of the Ultimatecut 4S Boost countersink from RUKO - developed for high-quality materials and precise countersinking. Only by using this tool was it possible to reliably achieve the required precision in machining the resistant material.
As the countersinks are close to the edge of the circular solid core insert, it was possible to machine them using a bench drill. This enabled clean and controlled processing to be realised. The result is precise countersinking and a flawless surface quality.
Advantages of the solution used:
- clean, low-vibration machining
- high precision with demanding materials
- optimum surface quality
This shows how crucial the choice of the right tool is for precise results in demanding applications.
Next steps
The finished base plate now serves as the basis for the planned optimisations. Among other things, claws can be hooked into special cut-outs (and removed again for cleaning) to support the containers. MADRID V2 will also have a type of crane that can lift the container lids automatically for refilling and measure the new fill level.
An overview of the existing dispensing system and the dispensing process can be found on the website (madrid-drinks.de).
A detailed video of the machine's development process is available at youtube.com/BodgedButWorks.
The MADRID project impressively demonstrates how innovative concepts in mechanical engineering and precise tools work together to enable new applications in practice.