Tactlets Bring Tactile Feedback to Objects with Custom 3D-Printed Inputs
Custom printed high-resolution controls for an electro-tactile output with integrated touch sensing, which can be placed on 3D objects.
Computer scientists from Saarland University and the University of Sydney have developed 3D-printed tactile feedback inputs, or custom printed controls, that can be placed on nearly any 3D object. In general, they provide haptic outputs and touch-sensing capabilities for ubiquitous, tangible, and wearable computing applications. The key in the Tactlets design is its 3D printing method, in this case FDM or Fused-Deposition Modeling or conductive inkjet printing, which allows them to incorporate electrically conductive material with the filament.
A Tactlet can be produced using almost any 3D printer that has a dual extrusion system, and are made using one or more taxels (tactile pixels), which can sense touch inputs. They can also be formed into a myriad of shapes depending on the applications, including several different types of sliders and buttons, for tactile inputs, outputs, tick marks, and dynamic ranges. For example, a Tactlet slider can be added to an audio device to create a volume control.
During the printing process, taxels are embedded into the FDM material using a conductive filament, each with a trace running to a part of the model that’s exposed so they can be connected to a Teensy 3.2 microcontroller. At that point, conductive or resistive touch circuits can be incorporated to detect when the Tactlet is being touched. The Teensy can then be programmed to detect how the Tactlet is being touched, whether it’s a sliding motion or being tapped, and so on.
Tactlets can be printed on most 3D objects, even with complex geometries. The researchers demonstrated the Tactlets capabilities by building a pair of novel haptic devices, such as a phone case with a slider that can be used to scroll through documents and a presenter device with tactile feedback for use with Microsoft PowerPoint. The team envisions Tactlets being used to provide tactile input/output controls for the rapid prototyping of new interactive objects, tangible interfaces, and other computing devices.