Page 142 - Read Online
P. 142

Sun et al. Soft Sci. 2025, 5, 18  https://dx.doi.org/10.20517/ss.2024.77        Page 19 of 26

               neuromorphic computing technology also shows significant potential in wearable devices, particularly in
               health monitoring. These smart health devices, including smartwatches and health-monitoring patches, use
               neuromorphic algorithms to monitor real-time physiological signals and predict health conditions. By
               modeling and predicting real-time signals through SNNs, these devices can detect early signs of health
               issues. For instance, a SNN can predict a user’s exercise or fatigue state based on heart rate patterns, even
               detecting potential health risks in advance. Researchers have developed a wearable, flexible sweat-sensing
               platform for real-time, multi-channel sweat analysis. Integrated ion electrophoresis modules enabled
               automatic and programmatic sweat extraction. These sensors held great potential for monitoring
               dehydration, diagnosing cystic fibrosis, drug monitoring, and non-invasive blood glucose detection
                                                                                                       [110]
               [Figure 7F].


               Robotic skin integrates skin-inspired sensors with neuromorphic computing, allowing robots to “feel” and
               perceive their environment. Using SNNs, the system processes sensory signals and quickly adjusts the
               robot’s actions based on tactile inputs such as touch pressure or object contact. A recent study designed a
               flexible tactile sensing array based on capacitive mechanisms, with a polyethylene terephthalate (PET)
               substrate, PDMS dielectric layer, and convex-concave contact layers. The PDMS layer featured four types of
               microstructures, enabling tactile feedback control for robotic arms, showing potential for obstacle
                        [111]
               avoidance .
               The multimodal perception system is also a type of integrated system that combines skin-inspired sensors
               and neuromorphic computing. These systems can simultaneously process tactile information, auditory
               information, and simulate the comprehensive processing capabilities of human senses. Data from sensor
               arrays, including tactile and sound sensors, are processed through neuromorphic computing units (e.g.,
               SNN). The system can perceive and learn based on the combined patterns of touch and sound, enabling
               more complex tasks such as intelligent voice control and touch-sound synchronization. Researchers have
               combined pressure-activated organic electrochemical synaptic transistors with artificial mechanoreceptors
               to detect the directional movement of object vibrations. By processing spike-encoded signals through a deep
               learning model, the spatiotemporal characteristics of tactile patterns were effectively distinguished,
                                              [112]
               achieving high recognition accuracy  [Figure 7G]. Another study proposed a multimodal bionic tactile
               sensor module capable of sensing surface geometries, forces, vibrations, and temperatures, exploring and
               mimicking human tactile perception capabilities .
                                                        [113]
               In recent years, significant progress has been made in the development of multimodal sensing systems. At
               the same time, such integrated systems often exhibit superior performance. We often focus on the system’s
               skin-inspired neuromorphic sensors, materials, sensitivity or accuracy, power consumption, response time,
               and their task to assess the system’s specific performance and the latest developments. An overview is
               provided in Table 1. However, as integrated systems, they still face several key limitations and challenges.
               Multimodal sensing systems typically require many sensors and significant computational resources,
               resulting in high energy consumption. Furthermore, the manufacturing costs of current sensing systems
               remain elevated, and their production processes are often complex, which presents a barrier to large-scale
               deployment and widespread application. For e-skin and robotic skin, long-term wearability and comfort
               still need further improvement. Specifically, in terms of simulating human skin, there is still room for
               enhancement in softness, breathability, and overall comfort. Integrated systems require larger sensor arrays,
               but these large arrays are prone to crosstalk, degraded performance, and difficulties in functional
               integration. Current research systems are typically small-scale, and substantial advancements will require
               further breakthroughs in materials, performance, and low energy consumption.
   137   138   139   140   141   142   143   144   145   146   147