【XWBOO Top News】 Touch is a form of people perceiving the external environment through the skin, which can mainly perceive the temperature, humidity, pressure, vibration, etc. from the outside world, and feel the shape, size, material, softness and hardness of the object. In recent years, the function of tactile sensors based on the principle of human touch has become more and more perfect, and it has a wide range of applications in the fields of the Internet of Things and big data.
Flexible tactile sensors are called "robots with bionic intelligent skin" and "electronic skin robots". Compared with traditional sensors, it can not only detect the characteristics of objects, but also have the functions of sensing different contact forces, hot and cold, humidity, vibration frequency and so on. This tactile sensor is usually composed of pressure sensor and strain sensor, in order to ensure firm contact with non-flat, rough and dynamic skin surfaces without hindering daily activities, flexible tactile sensor has low modulus, high tensile and good wear resistance, at the same time, flexible tactile sensor also has the characteristics of high sensitivity, lightweight, low cost and low power consumption.
In recent years, the application of intelligent robots has gradually been widely used, like vision and hearing, touch is also an important means for intelligent robots to perceive external information. Tactile sensors are similar to the "skin" of intelligent robots, which can improve the efficiency and intelligence of robots, and can also complete a variety of delicate and difficult work in more complex environments. For example, let the intelligent robot pour a glass of water, for us, touching the cup, starting to pour water, judging the amount of water, receiving a few points, sending to the designated position, putting down the cup, and other ordinary steps, but for the intelligent robot is a test.
Although haptic sensing technology has developed to a certain extent, there are still some problems, such as the lack of new materials for tactile sensors, no obvious breakthroughs in the working principle and technology of tactile sensors, and the dexterity of receiving instructions and performing operations is not satisfactory. And many research results are mostly in the laboratory stage, and there are quite few results that can be commercialized on a large scale.
Professor Zhou Wei's team from the School of Aeronautics and Astronautics of Xiamen University has long been committed to the research of sensors with higher sensitivity and human-like perception. Inspired by the structure composition of arthropods, they proposed to construct a bionic flexible tactile sensor, which can accurately sense the magnitude and direction of external forces and realize ultra-sensitive high-frequency dynamic force detection.
With a flexible matrix and a rigid microstructure, this arthropod-like "rigid and flexible" structure is constructed using new materials. In the past two years, they have been groping in epoxy resin, paraffin, polydimethylsiloxane, silica gel and other materials, repeatedly looking for the best combination, and finally groped for a fused "rigid and flexible" structure. This achievement provides a new working mode for the "skin" of the intelligent robot and greatly improves the sensitivity of the "skin" of the intelligent robot.
This bionic "rigid and flexible" flexible tactile sensor not only improves the force transmission efficiency of flexible materials, but also subverts the working mode of traditional piezoelectric flexible tactile sensors, so that the sensitivity of the sensor can reach 17 times the theoretical limit value, and has excellent performance of 5−600Hz wide bandwidth, 0.009−4.3N linear detection range and real-time force direction recognition.
The development and maturity of flexible tactile sensors have promoted their application and development in the fields of biomedicine, motion detection and human-computer interaction, thereby further promoting the development of intelligent systems. This achievement provides a new method and new idea for the in-depth research of piezoelectric tactile sensor, and has important theoretical research value and significance for the establishment of human-like tactile perception system by intelligent robots. The development of flexible tactile sensors with superior performance, easy to make, low cost and mass production is bound to be the future development direction, we can expect that tactile sensors will not only be suitable for intelligent robots, but also expected to be used in medical, automotive, wearable devices and other fields, bringing us more convenience.
(Source: Science and Technology Daily)
Original title: New progress in flexible tactile sensor research gives robots a keen "touch"
