On-skin Telehaptic Device Allows Users to Transmit Touch Remotely

December 13, 2022 by Jake Hertz

Attached to a user's fingertip, this new "telehaptic" prototype allows people to transmit touch remotely and in real time.

Augmented and virtual reality (AR/VR) is heralded as the next revolution in consumer electronics. Central to AR/VR is haptics, an interface technology that requires designers to create both natural and intuitive physical interactions with devices.


The telehaptic solution

The telehaptic solution designed by Electronics and Telecommunications Research Institute (ETRI) researchers. Image used courtesy of the ETRI


Recently, researchers from the Electronics and Telecommunications Research Institute (ETRI) in Seoul, South Korea, published a paper describing a significant advance in the field of "telehaptics." The team developed a device that attaches to fingertips to remotely transmit touch in real-time and provide a vivid tactile experience.


What is Telehaptics?

Haptics refers to technology that relies on touch to acquire information and manipulate objects. Most consumer devices employ some form of haptics, often taking the form of a vibration motor for devices like smartphones or watches.

Telehaptics, on the other hand, transmits computer-generated tactile sensations over networks. The goal of telehaptics is to send and receive tactile information from one device to another.


Telehaptic interaction

Conceptual illustration of how telehaptic solutions may be used for VR/AR interactions. Image used courtesy of Advanced Functional Materials


For example, a telehaptic glove may capture the tactile sensations of a user, transmit that information to another user, and then recreate those same sensations on the receiver. With this technology, the ultimate goal is to enable users to share tactile sensations and create shared virtual interactions.


The Tradeoffs of Telehaptics

Telehaptics relies on several components, including specialized sensors to capture tactile data, a wireless link to share data, and specialized tactile actuators to recreate tactile sensations.

One challenge here is that the number of components required for a telehaptic system results in large devices. Consider the previous example of a telehaptic glove. To make a system that is natural to use, the glove must be relatively lightweight, allowing for a comfortable user experience. The glove must also be flexible to contort to the shapes of the human hand as it moves.

However, with the number of unique components inside a telehaptic system, designers face a tradeoff for weight, flexibility, and functionality. Researchers are now rethinking solutions for telehaptic systems that are comfortable and flexible to wear without foregoing performance.


Researchers Find a Way to Instantly Transmit Touch Remotely

Research emerging from ETRI now describes a new, ultra-flexible on-skin telehaptic system worn on a user’s fingertip to transmit touch remotely and in real-time. 

To record tactile information, the researchers' device uses dual mechanism sensors that consist of a fast adaptive and slow adaptive mechanoreceptor-like pressure sensor array. With a frequency range from 1 HZ to 1 kHz, this array records static and dynamic pressures of the fingertip as it experiences tactile sensations. The collected tactile information is then amplified and processed by an off-the-shelf processing module worn on the back of the hand and eventually transmitted to the receiver.


A description of the researcher’s on-skin telehaptics solution

A description of the researcher’s on-skin telehaptic solution. Image used courtesy of Nature


Once this information is received, the system recreates tactile information through a specialized array of sub-millimeter-scale piezoceramic actuators. These actuators are specially designed to generate vibration patterns with a 1.8 mm pitch and high spatial resolution. Importantly, the actuator array is integrated on a flexible substrate using a cross-pattern to maintain flexibility while minimizing stress during mechanical deformation.

With this prototype, the researchers proved the feasibility of a flexible telehaptic system that doesn't sacrifice performance. The researchers hope to eventually build off this prototype to create a more complete system.