The complexity of human-machine interactions has increased steadily in recent years. This is partly due to the ever-increasing technological possibilities. The users are therefore often overwhelmed with the operation of new devices. In order not to increase the operating effort with the increasing complexity of the devices, new operating concepts are to be developed. One possibility for this is the utilisation of currently little-used sensory channels, such as the tactile perception.
Dielectric elastomer stack actuators offer the possibility to design novel interaction concepts with tactile feedback. They can be used for both input and output.
In cooperation with the Institute of Electromechanical Design (EMK) and the Institute of Printing Science and Technology, the Institute of Ergonomics & Human Factors (IAD) of the TU Darmstadt develops ideas for applications of Dielectric Elastomer Stack Actuators. In particular, the IAD examines the perception of concave, tactile feedback.
The following questions, among others, are being investigated within the framework of the research project:
- Which applications are dielectric elastomer stack actuators suitable for?
- Which parameters influence the perception of the concave tactile feedback?
- How should the feedback of the elastomer stack actuators be designed to be perceived by a user?
A literature analysis was used to determine which technical and human-related parameters have an effect on human tactile perception. These were then analysed in user studies on various aspects of tactile perception and recognition when using concave feedback and dielectric elastomer stack actuators. Subsequently, design guidelines for this type of tactile feedback were derived.
The following studies were carried out:
Study 1: Influence of size, form and depth of a concave shape on tactile perception
Study 2: Influence of material, age and gender on shape perception and recognition
Study 3: Influence of movement on shape perception
Study 4: Influence of frequency on the recognition of concave shapes
Study 5: Use of tactile feedback for the blind navigation of a computer at the workplace
The results show that tactile feedback from dielectric elastomer stack actuators can be used to complete blind navigation tasks. It is also shown that the distance between the actuators is more important than their surface area.
Kauer, M., Röbig, S., Maus, H., Mößinger, H., & Bruder, R. (2015). Using dielectric stack actuators for blind navigation with a tactile computer mouse. In: Proceedings 19th Triennial Congress of the IEA, 9.-14. August 2015, Melbourne, Australien.