Researchers led by City University of Hong Kong (CityU) has developed a wireless, soft e-skin. This e-skin is placed on top of the skin where it can both detect and deliver the sense of touch. The deeper the sender presses, the stronger and longer the sensation generated on the other e-skin. The researchers foresee that this development can enhance distance touch communication in a virtual reality.
“With the rapid development of virtual and augmented reality (VR and AR), our visual and auditory senses are not sufficient for us to create an immersive experience. Touch communication could be a revolution for us to interact throughout the metaverse,” said Dr Yu Xinge, Associate Professor in the Department of Biomedical Engineering (BME) at CityU.
E-skin to communicate in touch
While there are numerous haptic interfaces in the market to simulate tactile sensation in the virtual world, they provide only touch sensing or haptic feedback. The uniqueness of the novel e-skin is that it can perform self-sensing and haptic reproducing functions on the same interface. In other words: you can feel touch and sent touch to someone else with the same device making it possible to communicate in touch.
The electrical skin is a patch-like device containing 16 flexible actuators. These sensors consist of a flexible coil, soft silicone support, a magnet, and a thin polydimethylsiloxane (PDMS) film. The touch sensing and haptic feedback functions are based on electromagnetic induction. Part of the patch are also a microcontroller unit (MCU), Bluetooth module and other electronics on a flexible circuit board. All components are combined in a 7cm by 10 cm, 4.2 mm thick device.
Data sent via Bluetooth
Once the actuator on one patch is pressed and released, it sends electrical signals for tactile sensation to a corresponding actuator in another e-skin patch. The deeper the sender presses, the stronger and longer the sensation generated on the other e-skin. Then the electrical signal is converted into a digital signal by an analog-to-digital converter on the circuit board of the patch. The data is transmitted by Bluetooth.
When the other e-skin patch received the signal, it reproduces the haptic feedback through machinal vibration. The process can also be reversed to deliver vibrations to the receivers e-skin. Although each actuator can perform only one task at a time, the rest of the 15 actuators on the e-skin can supplement each other and perform the sensing or haptic reproducing function. Therefore, the e-skin allows for bidirectional touch.
IoT for touch
“Our e-skin can communicate with Bluetooth devices and transmit data through the internet with smartphones and computers to perform ultralong-distance touch transmission, and to form a touch Internet of Things (IoT) system, where one-to-one and one-to-multiple touch delivery could be realised. Friends and family in different places could use it to ‘feel’ each other,” said Dr Yu. “This form of touch overcomes the limitations of space and greatly reduces the sense of distance in human communication.”
The research findings were published in the scientific journal Science Advances under the title “Touch IoT enabled by wireless self-sensing and haptic-reproducing electronic skin”. Next, the research team will focus on practical applications for people with visually impairment, who could wear the e-skin to gain remote directional guidance and read Braille messages.
These researchers developed the e-skin
The first co-authors are Dr Li Dengfeng, then-postdoc on Dr Yu’s research team, Dr Yao Kuanming, postdoc in BME, Mr Zhou Jingkun and Mr He Jiahui, both PhD students in BME at CityU, and Ms Liu Sitong from Dalian University of Technology (DUT). Corresponding authors are Dr Yu, Professor Xie Zhaoqian from DUT, and Dr Dai Yuan from Tencent Robotics X. The research was supported by CityU and the Hong Kong Research Grants Council.
More can be found here: https://www.cityu.edu.hk/research/stories/2023/02/23/cityu-develops-wireless-soft-e-skin-interactive-touch-communication-virtual-world
