Embedded Haptic Waveguides to Improve Tactile Feedback : Designing a custom 3D-printed surface to enhance signal mediation

The physical properties of an interaction surface can significantly alter the characteristics of a vibration signal during its transmission from the actuator to the point of contact. This distortion can integrate and attenuate the applied signal before it reaches the skin contact significantly altering the intended perception. Thus, efforts need to be made to identify and regulate vibration mediation throughout the entire device to achieve uniform global vibrotactile-feedback. Our research proposes a novel concept of 3D-printing Embedded Haptic Waveguides (EHWs) within the interaction surface to improve signal propagation. The EHWs are designed to lower impedance load, effectively creating multiple mediation channels to relay actuation throughout the device. To evaluate the efficiency of our EHW design we compare it to three commonly used off-the-shelf materials (Gorilla glass, Plexiglas, aluminum) and one unmodified 3D-printed ABS surface. Results indicate that the customized 3D-printed EHW surface was more efficient at signal propagation and created similar perceptual feedback throughout the entire surface for the applied signals. These findings suggest that the EHW design has the potential to enhance global-device actuation for surface-based interaction in mobile and handheld devices.