A Flexible Dual-Mode Capacitive Sensor for Highly Sensitive Touchless and Tactile Sensing in Human-Machine Interactions

Human-machine interaction(HMI) is extensively employed in various applications such as robotic control and augmented reality/virtual reality. However, HMIs are mainly based on single-interaction mode, requiring bulky equipment to be worn or sustaining physical contact with the interfaces, resulting in limited interaction efficiency and intelligence. Here, it proposes a novel flexible dual-mode capacitive sensor using 12 sensing units for touchless and tactile sensing during HMIs, the sensor has a labyrinth-patterned electrode to improve the performance of proximity sensing and a truncated pyramid-shaped porous hierarchical dielectric structure to improve the pressure sensing performance. The fabricated dual-mode sensor is characterized by a high proximity detection range of up to 110 mm, the pressure detection range is from 0 to 200 kPa with a sensitivity of 0.464% kPa-1. Further, the dual-mode sensor exhibits excellent discrimination between proximity and pressure signals, along with remarkable stability and repeatability. Then, a touchless-tactile HMI platform is developed for real-time control of robotics through accurate perception of touchless hand gestures and contact-pressing interactions. This platform demonstrates the superior dual-mode sensing performance of the sensor and validates its potential in future intelligent HMI scenarios. A novel flexible dual-mode capacitive sensor is developed for touchless and tactile sensing during human-machine interactions. The sensor has a labyrinth-patterned electrode to improve the performance of proximity sensing and a truncated pyramid-shaped porous hierarchical dielectric structure to improve the pressure sensing performance. Touchless-tactile HMI demonstrates the superior dual-mode sensing performance and application potential of the sensor.image