The fourth dimension: fragrances are introduced to virtual reality


© Fraunhofer EMFT/Bernd Müller
Smallest silicon micromembrane pump in the world with dimensions of 3.5 x 3.5 x 0.6 mm^3

Getting a bird’s eye view of the world or traveling to the lowest point of the Earth – all this can be done very conveniently nowadays from the living room couch with the help of Virtual Reality (VR). VR technologies for hearing and seeing have been almost perfected, but one key sensory perception is still lacking – that of smell.

In the project Scent – the Fourth Dimension for Virtual Reality, Fraunhofer EMFT and Fraunhofer IVV scientists are developing an innovative fragrance dosage system to be positioned close to the nose that can produce new smells at every breath. This joint work is based on a design tool that defines not just the chemical properties of the odorants but also the pump-specific parameters and the dimensions of the fluidic components. With defined input parameters, the tool releases the required dosage volume for each individual odorant to be pumped out of the reservoir to the nose. The odor molecules are contained in the reservoir in a gas phase, with a separate unit being required for each odorant. One key requirement in being able to realize this complex dosage system is the extremely miniaturized pumps created by Fraunhofer EMFT, measuring just 3.5 x 3.5 mm² (see picture).

In addition to the fluidic components already mentioned, researchers at Fraunhofer EMFT have also developed a new high-voltage driver for micropumps which can operate up to four micropumps via a single channel. In order to avoid unwanted aromas and ensure that the smells change at each breath, an internal Fraunhofer Discover project (funding reference no. 835196) developed a breathing cycle detector based on an environment sensor. This system is able to detect far enough in advance when the next inhalation will occur, allowing the required quantity of odor molecules to be emitted at each breath.


  • Fraunhofer Institute for Process Engineering and Packaging IVV