The Schnapsbomber is a project that was realized at the Munich University of Applied Sciences during the winter semester 2016/17.

In the team of 13 people we have developed a drinking game, which can be played from two persons. When the lid is opened, the game starts and a variable countdown begins. The Schnapsbomber is passed on to the next player in turn. Depending on how heavily the box is shaken the countdown will be reduced for seconds or the bomb will be ‘exploded’. As soon as the bomb explodes, the player has to take the shot glass out of the box within ten seconds, fill the glass, drink and put it back.

The team has divided into five working groups: design, tracks, digital printing/laser, programming, screen printing/pick & place.


design2The side panels adorn a simple, graphic game guide in comic style. On the lid the Schnapsbomber logo shines in bright, striking colors. The names of all participants are listed on the bottom, a QR code leads to the website:

The design was implemented in Adobe InDesign and Adobe Illustrator.

Digital printing / laser / plotter

druckThe Schnapsbomber is composed of three printed and two unprinted components.

– the box itself
– a lid
– the inlay
– the contact breaker holder
– a double bottom

The individual elements were laminated to protect the surface and give them a more high-quality look. The parts were punched with the laser engraver/plotter, then manually grinded, folded and glued together. The unnecessary areas of the foil with the tracks were cut out too.

Working group “Tracks”

leiterbahnenThe design of the cutting dies and the tracks were implemented in Adobe Illustrator. The cutting dies include:

– inlay (combined by a plug-in system)
– double bottom
– contact breaker holder (supports the inlay and prevents slipping)
– box
– separate lid for plug on

Additionally, the complete creation of the tracks, in consideration of the switch, the chip, the LEDs and the resistors. A circuit diagram of the programming team, which was adapted to the LEDs, the microchip, the inlay and the size of the box, served as a template. After several optimization of the track file, a laser file was created to enable a flexible fit into the box.

Working group “Programming”


The team’s challenge was to develop a usable program code for the Arduino physical computing environment. An Arduino UNO and a second same type with removable chip were used during the development and test phase. For the boxes, only the Arduino UNO, an ATMega 328p was used.

In addition are used:

– piezoelectric vibration sensor from Sparkfun
– capacitive sensor made of copper
– small loudspeaker for sound output
– seven SMD LEDs

With the help of Bachelorand Simon Jilg, a working circuit diagram could be designed to connect our chip to all components.

The programming of the game logic and the creation of the interface for the rest of the system are important for the working group. This enables a smooth integration of the chip and communication with all other components. The code consists of several parts which each carry out certain tasks in the overall system and allow the correct interaction of all the elements used. It operates internally in tenth of a second intervals and also uses this time to check and process measured values. However, it is only communicated to the outside of the game environment every second.

The countdown starts with a random value between 30 and 60 seconds. It reduces faster depending on the way the players play, while also being represented acoustically by a typical countdown sound. Here, the speed of the sound starts to double from 30 seconds. In the last five game seconds the sound is five times faster than before to signal the approach to the end.

Depending on the values the system receives from the vibration sensor and the capacitive sensor, the countdown is reduced by two to five seconds in a five step increment. The intensity of the vibration is visualized inside the box by means of LEDs. Within the last three playing seconds, the LED below the shot glass is blinking five times per second, similar to the countdown sound.

Screen printing of the tracks, as well as the setting of the LEDs.

silberbahnThe tracks printed with silver color are ultimately responsible for the conductivity and thus the functioning of the electronics.

The on foils printed tracks contain recesses for the LEDs, their resistors and the chip. If the silver paste is dry, use the Pick & Place to place the LEDs exactly in the gaps provided for this purpose.

Two adhesive spots are applied for the micro luminaires in order to fix them on the track. It’s important that the two poles do not touch, as this may lead to a short circuit.

The resistors to the respective LEDs and the chip are also set by Pick & Place technology.