ActuatorsΒ are the moving part of a device that controls the mechanism of a system. A simple example of an actuator is the opening of a valve. With this simple example of a solenoidal valve, we can understand that an actuator (or, in other words, a part that performs a movement in a specific direction) needs a control signal along with the source of energy. The control signals are relatively low energy in the form of voltage or current. The control system can be software-based, a human, or any other input. Combining actuators with mixed reality applications can open up a whole new world of interaction.Β Mixed realityΒ refers to combining real and virtual worlds for producing new environments and visualizations.
With mixed reality, physical and digital objects can co-exist and interact in real-time. A team of researchers from theΒ University of ChicagoΒ recently publishedΒ an articleΒ on a foldableΒ haptic actuatorΒ for rendering touch in Mixed Reality. This device is developed to provide an interactive environment where the user can touch a virtual object. The device provides feedback to mixed reality (MR) environments by pressing against the userβs fingerpad when a user touches a virtual object. It provides low-frequency vibrations on the finger contact points. The device is calledΒ Touch&Fold, and it is designed to fit on a userβs fingernail. When the device is not in use (when the user is touching real-world objects), the device folds back on top of the userβs nail.
Touch&FoldΒ features a linear resonant actuator that allows rendering not only touch contacts (i.e., pressure) but also textures (i.e., vibrations). The device is wireless and self-contained. It measures onlyΒ 24Γ24Γ41 mmΒ and weighsΒ 9.5 g. The actuation takes only 92 milliseconds.