Bionic Device Research Articles

E-Skin and Its Advanced Applications in Ubiquitous Health Monitoring.

E-skin is a bionic device with flexible and intelligent sensing ability that can mimic the touch, temperature, pressure, and other sensing functions of human skin. Because of its flexibility, breathability, biocompatibility, and other characteristics, it is widely used in health management, personalized medicine, disease prevention, and other pan-health fields. With the proposal of new sensing principles, the development of advanced functional materials, the development of microfabrication technology, and the integration of artificial intelligence and algorithms, e-skin has developed rapidly. This paper focuses on the characteristics, fundamentals, new principles, key technologies, and their specific applications in health management, exercise monitoring, emotion and heart monitoring, etc. that advanced e-skin needs to have in the healthcare field. In addition, its significance in infant and child care, elderly care, and assistive devices for the disabled is analyzed. Finally, the current challenges and future directions of the field are discussed. It is expected that this review will generate great interest and inspiration for the development and improvement of novel e-skins and advanced health monitoring systems.

Design and Experiment of In-Situ Bionic Harvesting Device for Edible Sunflower

In view of the low degree of mechanization and poor quality of harvesting of edible sunflower after drying, an in situ bionic harvesting device was designed, which can achieve low-loss harvesting of edible sunflower without removing the edible sunflower disc. According to the physical characteristics of sunflower stalks in the field, influencing factors of in situ low-loss feeding were obtained, and the structural parameters of the in situ feeding mechanism were determined. Based on bionic technology and static analysis, the influencing factors on the performance of the bionic threshing mechanism were obtained. By analyzing the mechanical characteristics of edible sunflower seed, the operation parameters of the seed collection mechanism were determined. Based on the structural analysis results of the harvesting device, a response surface optimization test was carried out. The test results show that when the average rotation speed of the bionic loosening roller was 113.57 rpm, the average rotation speed of the simulated artificial striking roller was 230.80 rpm, the average forward speed of the harvesting device was 0.58 m/s, the working quality of the harvesting device was the best, the seed loss rate was 2.12%, and the edible sunflower disc threshing rate was 98.96%. A field verification test further confirms that under the optimal working parameters, the relative deviation between test indexes and response surface optimization test results was less than 2%. During the operation process, the movement of key components of the harvesting device was coordinated and stable. The research results can provide new ideas for the mechanized harvesting of the edible sunflower disc after drying.

Design of gelatin-based bionic device for neural computing applications

This study introduces an approach to the development of resistive random-access memory (RRAM) devices by utilizing gelatin-based materials and incorporating an ultrathin Al2O3 interface layer fabricated using atomic layer deposition (ALD). The integration of the ALD technology for Al2O3 deposition ensures precise control over the layer thickness and quality, contributing to enhanced device uniformity and stability. The AGAI device can withstand more than 200 switching cycles while maintaining a high ON/OFF ratio exceeding 103, and it also successfully emulates synaptic plasticity characteristics, including long-term synaptic plasticity and short-term synaptic plasticity, as demonstrated by their responses to paired-pulse facilitation and paired-pulse depression, respectively, thereby validating their potential for neural computing applications. Additionally, the hybrid conduction mechanism in the AGAI device, involving aluminum and oxygen vacancy filaments, provides remarkable control over the switching process, leading to repeatability in synaptic characteristics and resistance states. These capabilities introduce new possibilities for the development of neuromorphic computing systems, which aim to mimic the functionality of the human brain in processing and storing information.

A3-DOF frog-inspired quasi-zero stiffness isolator and its vibration control performance

To pursue a nonlinear isolator with simpler structure, better load adaptability, and wider quasi-zero stiffness (QZS) region, a 3-DOF bionic vibration isolation device is proposed and analyzed inspired by the superior landing performance of the frog's leg structure. The mechanism's dynamical equation is established using Lagrange's principle. The dynamic model is validated using ADAMS simulation. The effects of spring stiffness and rod length on static mechanical characteristics are analyzed. The vibration attenuation performance of the structure is analyzed under independent three-directional excitation and three-directional coupled excitation. Compared with the typical X-shaped QZS isolator and the traditional QZS isolator, the designed structure's advantages is demonstrated. By tuning the parameters and building a control route based on variable-stiffness dielectric elastomer, optimization of the device's vibration isolation performance under coupled excitation was accomplished.

Attachment performance analysis and experimental study of lunar rock bionic attachment device based on DEM-MBD

Lunar rock sampling is an important means of studying the evolutionary history of planets. However, facing the special microgravity environment of the Moon, general rock sampling drills cannot provide the torque and pressure required for the mission. Therefore, it is of great significance to study the sampling drill with attachment function. In this study, the claw spines of insects were simulated, and a biomimetic spine laminated structure with flexible connections was designed. The working principle of attachment and detachment was analyzed using a rod model with elastic characteristics. The process of biomimetic spines attaching to rough surfaces was simulated using the coupling method of multi-body dynamics and discrete element analysis (MBD-DEM). The mechanical properties of bionic claws during attachment were analyzed. Mechanical experiments were conducted on biomimetic spines attached to volcanic rock. The experiment results for single and multiple spines were compared with the simulation results, verifying the accuracy and reliability of the simulation model. Finally, A bionic attachment prototype was designed and tested for performance. The attachment device was integrated into a sampling drill and drilling experiments were conducted. This article provides important reference for the optimization of biomimetic spine structures, along with adding value to the design of attachment equipment.

Fingerprint-inspired biomimetic tactile sensors for the surface texture recognition

A bionic tactile device is designed for object surface texture recognition, taking inspiration from the microstructure of human fingerprints. The sense of touch in humans is achieved through the frictional vibration and generation of electrical potential signals by subcutaneous receptors. Constructing a tactile sensing device involves generating distinct signals upon interacting with different materials. The piezoelectric film PVDF is particularly suitable as a sensitive material for sensors due to its excellent flexibility, strong mechanical strength, excellent dynamic response and cost-effectiveness. This paper presents the design of a PVDF-based fingerprint-inspired tactile sensor capable of differentiating various textures. By combining the collected signals with machine learning algorithms, diverse textures can be effectively identified. To demonstrate the sensor’s superior performance, two experiments were conducted—one focused on recognizing different material textures, and the other on recognizing Braille characters. The accuracy achieved in these experiments was 97.4% and 96.5%, respectively, highlighting the technology’s significant potential in intelligent robotics and human-computer interaction.

Biomimetic computer-to-brain communication enhancing naturalistic touch sensations via peripheral nerve stimulation

Artificial communication with the brain through peripheral nerve stimulation shows promising results in individuals with sensorimotor deficits. However, these efforts lack an intuitive and natural sensory experience. In this study, we design and test a biomimetic neurostimulation framework inspired by nature, capable of “writing” physiologically plausible information back into the peripheral nervous system. Starting from an in-silico model of mechanoreceptors, we develop biomimetic stimulation policies. We then experimentally assess them alongside mechanical touch and common linear neuromodulations. Neural responses resulting from biomimetic neuromodulation are consistently transmitted towards dorsal root ganglion and spinal cord of cats, and their spatio-temporal neural dynamics resemble those naturally induced. We implement these paradigms within the bionic device and test it with patients (ClinicalTrials.gov identifier NCT03350061). He we report that biomimetic neurostimulation improves mobility (primary outcome) and reduces mental effort (secondary outcome) compared to traditional approaches. The outcomes of this neuroscience-driven technology, inspired by the human body, may serve as a model for advancing assistive neurotechnologies.

A light-responsive poly(urethane-urea) actuator with room temperature self-healing performance

Light-responsive actuators with self-healing properties and super mechanical strength at room temperature are critical for practical applications. However, optimizing both of these properties on a single actuator is extremely challenging. Herein, a novel light-responsive poly(urethane-urea) actuator (PIBS-0.75) with room temperature self-healing performance has been successfully prepared. The PIBS-0.75 light-responsive actuator not only exhibits excellent self-healing properties (heals for 8 h at room temperature and regains 91.16 % of its original tensile strength), but also shows high tensile strength (15.52 MPa) and good fracture strain (over 600 %). Moreover, a bionic light-responsive device with room temperature self-healing properties has been successfully fabricated to imitate human gestures of greeting. By incorporating the room temperature self-healing ability into the light-responsive actuator, this work would pave a new way for the development of durable and sustainable light-responsive actuators.

The Design and Experimental Validation of a Biomimetic Stubble-Cutting Device Inspired by a Leaf-Cutting Ant's Mandibles.

Under the conditions of conservation tillage, the existence of the root-soil complex greatly increases the resistance and energy consumption of stubble-cutting blades, especially in Northeast China. In this research, the corn root-soil complex in Northeast China was selected as the research object. Based on the multi-toothed structure of the leaf-cutting ant's mandibles and the unique bite mode of its mandibles on leaves, a gear-tooth, double-disk, bionic stubble-cutting device (BSCD) was developed by using a combination of power cutting and passive cutting. The effects of rotary speed, tillage depth, and forward speed on the torque and power of the BSCD were analyzed using orthogonal tests, and the results showed that all of the factors had a large influence on the torque and power, in the order of tillage depth > rotary speed > forward speed. The performance of the BSCD and the traditional power straight blade (TPSB) was explored using comparative tests. It was found that the optimal stubble-cutting rate of the BSCD was 97.4%. Compared with the TPSB, the torque of the BSCD was reduced by 15.2-16.4%, and the power was reduced by 9.2-11.3%. The excellent performance of the BSCD was due to the multi-toothed structure of the cutting edge and the cutting mode.

The impact of bionic prostheses on users' self-perceptions: A qualitative study

Bionic devices for reestablishing or augmenting users' capabilities (e.g., bionic prostheses or exoskeletons) are becoming increasingly common. While prior research examined how such devices affect others' perceptions of their users, little is known about how these devices affect users' self-image and -perception, and the corresponding theory is scarce. To account for this gap, we conducted semi-structured interviews with users of bionic upper limb prostheses to obtain insights into their self- and meta-perceptions. Results of our qualitative analysis indicate that using bionic prostheses influences the social (self-) perception of bionics users in multiple ways, such that users describe themselves as being seen as more competent by others and treated differently after receiving the bionic prosthesis in comparison to simpler models. Results imply a somewhat complex dual identity among users in the sense that the bionic device instills competence, but disability-related feelings of stigma are present simultaneously. Despite being exploratory, our findings thus indicate that using bionic devices affects users' self-perception, stereotypes, and interpersonal perceptions. The ongoing proliferation of restoring devices and the introduction of augmenting technologies in future work contexts, for example, might thus have unintended social consequences that need to be accounted for.

Regulation mechanism of bionic wireless power device thermal management system based on nanofluids and magnetic field

For further optimal power conservation and dissipation performance of wireless power devices, this paper presented a cooling system that couples a wave bionic surface structure with composite magnetic nanofluids. Heat transfer mechanisms near the wall of the channel under magnetic field excitation have been developed. Effect of changes in the near-wall thermal boundary layer on the integral heat transfer was analyzed, and a comprehensive evaluation of the model performance was given. The outcomes revealed that as the flow approaches the crest, the difference in thermal boundary layer thickness for different flow Reynolds numbers becomes small, and in the flow region in the second half of the wave crest, the thermal boundary depth is no longer regular at different Reynolds numbers, which is due to the “detached flow”. “Detached flow” effectively breaks the thermal boundary enhancing the heat transfer performance. Temperatures excited by magnetic forces show disordered “jumps”, and the heat transfer characteristics are substantially improved by 41.59 % under magnetic field. Comprehensive evaluation index under magnetic field excitation is up to 1.54 for wave bionic surfaces with a frequency of 20 rad/s.

Comparative Analysis of the Hydrodynamic Performance of Dual Flapping Foils with In-Phase and Out-of-Phase Oscillations

In the context of the plain river network, conventional water pumps suffer several drawbacks, including inadequate efficiency, poor security, and costly installation costs. In order to improve the hydrodynamic insufficiency problem and enhance the hydrodynamic performance and applicability of flapping hydrofoils, this paper proposes a bionic pumping device based on dual flapping foils. Based on the finite volume method and overlapping grid technology, the numerical simulation and experimental verification of the hydraulic performance of two typical motion modes of in-phase and out-of-phase oscillations are conducted, thereby providing a theoretical foundation for improving and optimizing the design of flapping hydrofoils. The results show that the out-of-phase oscillation has better hydraulic performance compared to the in-phase oscillation. The formation of the tail vortex structure plays a crucial role in determining the hydraulic efficiency of dual flapping foils, with in-phase oscillation forming a pair of vortex streets and out-of-phase oscillation forming two pairs of vortex streets. The pumping efficiency of the out-of-phase oscillation is significantly higher than that of the in-phase oscillation, reaching up to 38.4% at a fixed frequency of f = 1 Hz, which is an increase of 90.5% compared to the in-phase oscillation. The characteristic curve of the in-phase oscillation shows an “S” type unstable oscillation phenomenon, namely the hump phenomenon, while the out-of-phase oscillation does not show such a phenomenon, which can effectively expand its application range. In addition, the applicable head of the out-of-phase oscillation hydrofoil is lower, which can better meet the requirements of ultra-low head conditions.

Bioinspired Luminescent HOF-Based Foam as Ultrafast and Ultrasensitive Pressure and Acoustic Bimodal Sensor for Human-Machine Interactive Object and Information Recognition.

Bionic sensors have extensively served smart robots, medical equipment, and flexible wearable devices. The luminescent pressure-acoustic bimodal sensor can be treated as a remarkable, multifunctional, integrated bionic device. Here, a blue-emitting hydrogen-bonded organic framework (HOF-TTA) as luminogen combines with melamine foam (MF), generating the flexible and elastic HOF-TTA@MF (1 and 2) as a pressure-auditory bimodal sensor. In the luminescent pressure sensing process, 1 has excellent maximum sensitivity (132.02kPa-1 ), low minimum detection limit (0.0 1333Pa), fast response time (20ms), high precision and great recyclability. 2 as a luminescent auditory sensor exhibits the highest response to the 520Hz sound at 255-1453Hz. In the process of sensing sound at 520Hz, 2 possesses high sensitivity (1 648 441.3cpsPa-1 cm-2 ), low detection limit (0.36dB) and ultrafast response time (10ms) within 11.47-91.77dB. The sensing mechanisms toward pressure and auditory are analyzed in detail by finite element simulation. Furthermore, 1 and 2, as a human-machine interactive bimodal sensor, can recognize nine different objects and word information of "Health", "Phone", and "TongJi" with high accuracy and strong robustness. This work provides a facile fabricated method of luminescent HOF-based pressure-auditory bimodal sensors and endows them with new recognition functions and dimensions.

A bionic profiling-energy storage device based on MBD-DEM coupled simulation optimization reducing the energy consumption of deep loosening

A novel bionic profiling energy storage device was designed in this research to reduce the energy consumption of deep loosening operations. As the core technology of conservation tillage, deep loosening has always been difficult to promote on a large scale in the Phaeozem region of Northeast China due to its high energy consumption. The deep loosening mechanism is mainly composed of deep loosening shovel and energy-storage profiling device. At present, optimizing the structure of deep loosening shovel to reduce consumption was the main research method in this field, but it is still difficult to meet the production demand. At the same time, energy storage-profiling device has been neglected by researchers for a long time because of the lack of suitable mechanism innovation ideas and efficient experiment optimization methods. Based on the excellent soil excavation capability of the hare, the bionic energy storage-profiling device (BSPD) was innovatively designed by drawing the unique mechanism of its fore-upper limb, and the MBD-DEM coupled simulation technology was proposed as the experimental optimization method. It was found that BSPD has significant advantages in flexible profiling, tillage depth control, elastic energy storage and deep loosening resistance reduction capabilities compared with traditional self-excited energy storage-profiling devices (SSPD) by the analysis methods of least significant difference (LSD), Regression Analysis and Redundancy analysis (RDA), based on the results of MBD-DEM coupled simulation experiments. In addition, it was found that the torsional elastic coefficient, as the core design parameter of BSPD, also had a significant impact on the above four capabilities, and its optimal value was obtained by the established torsional elastic coefficient-deep loosening energy consumption regression model. The field experiment results showed that the deep loosening energy consumption of BSPD was 16.2% lower than that of SSPD and filed experiment results also verified the accuracy of MBD-DEM coupled simulation results. In summary, this study found a more effective new research path in addition to the traditional deep loosening consumption reduction research methods, and provided mechanism innovation design ideas and experimental optimization methods for the research and development of agricultural soil-engaging components.

Study on the Mechanism of Motion Interaction between Soil and a Bionic Hole-Forming Device

Due to the lack of water resources, the main agricultural planting method used in the northwest region of China is plastic film mulching, with precision hole sowing performed on the film after mulching. However, conventional hole-forming devices damage the compactness of the soil hole while moving on the plastic film, causing seed misplacement. Therefore, this study designed a bionic hole-forming device based on the oriental mole cricket. In order to explore the interaction between the hole-forming device and the soil, a typical soil discrete element particle model was established, and its contact parameters were calibrated. An experiment was conducted to compare the performance of the bionic hole-forming device with a conventional device using discrete element method and multi-body dynamics (DEM-MBD) coupled simulations. The results revealed that the bionic hole-forming device caused less soil disturbance during the hole-forming process and could reduce the sowing operation resistance compared to the traditional device. Compared to traditional square and cone-shaped hole-forming devices, the soil resistance of the bionic hole-forming device was the smallest, at 7.51 N. This work provides a reference for the optimization of hole-forming devices for plastic film sowing.

Simple cyclic memristive neural networks with coexisting attractors and large-scale amplitude control.

The memristor's unique memory function and non-volatile nature make it an ideal electronic bionic device for artificial neural synapses. This paper aims to construct a class of memristive neural networks (MNNs) with a simple circular connection relationship and complex dynamics by introducing a generic memristor as synapse. For placing the memristive synapse in different coupling positions, three MNNs with the same coupling cyclic connection are yielded. One remarkable feature of the proposed MNNs is that they can yield complex dynamics, in particular, abundant coexisting attractors and large-scale parameter-relied amplitude control, by comparing with some existing MNNs. Taking one of the MNNs as an example, the complex dynamics (including chaos, period-doubling bifurcation, symmetric coexisting attractors, large-scale amplitude control) and circuit implementation are studied . The number of equilibria and their stabilities are discussed. The parameter-relied dynamic evolution and the coexisting attractors are numerically shown by using bifurcations and phase portraits. A microcontroller-based hardware circuit is given to realize the network, which verifies the correctness of the numerical results and experimental results.

High-Contrast Bidirectional Optoelectronic Synapses based on 2D Molecular Crystal Heterojunctions for Motion Detection.

Light-stimulated optoelectronic synaptic devices are fundamental compositions of the neuromorphic vision system. However, there are still huge challenges to achieving both bidirectional synaptic behaviors under light stimuli and high performance. Herein, a bilayer 2D molecular crystal (2DMC) p-n heterojunction is developed to achieve high-performance bidirectional synaptic behaviors. The 2DMC heterojunction-based field effect transistor (FET) devices exhibit typical ambipolar properties and remarkable responsivity (R) of 3.58×104 A W-1 under weak light as low as 0.008mW cm-2 . Excitatory and inhibitory synaptic behaviors are successfully realized by the same light stimuli under different gate voltages. Moreover, a superior contrast ratio (CR) of 1.53×103 is demonstrated by the ultrathin and high-quality 2DMC heterojunction, which transcends previous optoelectronic synapses and enables application for the motion detection of the pendulum. Furthermore, a motion detection network based on the device is developed to detect and recognize classic motion vehicles in road traffic with an accuracy exceeding 90%. This work provides an effective strategy for developing high-contrast bidirectional optoelectronic synapses and shows great potential in the intelligent bionic device and future artificial vision.

A microfluidic device inspired by leaky tumor vessels for hematogenous metastasis mechanism research.

Endothelial intercellular pores of tumor vessels generally lead to enhanced interstitial flow and may facilitate the migration of tumor cells. The permeability of tumor vessels causes a concentration gradient of growth factors (CGGF) from blood vessels to tumor tissues, which is opposite to the direction of interstitial flow. In this work, exogenous chemotaxis under the CGGF is demonstrated as a mechanism of hematogenous metastasis. A bionic microfluidic device inspired by endothelial intercellular pores of tumor vessels has been designed to study the mechanism. A porous membrane vertically integrated into the device using a novel compound mold is utilized to mimic the leaky vascular wall. The formation mechanism of the CGGF caused by endothelial intercellular pores is numerically analyzed and experimentally verified. The migration behavior of U-2OS cells is studied in the microfluidic device. The device is divided into three regions of interest (ROI): primary site, migration zone, and tumor vessel. The number of cells in the migration zone increases significantly under the CGGF, but decreases under no CGGF, indicating tumor cells may be guided to the vascellum by exogenous chemotaxis. Transendothelial migration is subsequently monitored, demonstrating the successful replication of the key steps in vitro in the metastatic cascade by the bionic microfluidic device.

A novel bionic packed bed latent heat storage system filled with encapsulated PCM for thermal energy collection

• A bionic structure brings a more homogeneous temperature difference and a smaller pressure drop compared with conventional systems. • The parameters related to heat transfer and phase transition acquired from numerical study were validated by experiments. • A non-local thermal equilibrium model was employed to characterize the temperature distribution of PCM and HTF in porous media. • The enhancement of flow resistance and heat exchange performance was evaluated. The main content of this work is to propose a novel bionic solution to overcome the nonuniformity of flow and temperature distribution, which is an inherent problem and restriction for conventional latent heat storage devices. By learning from animal circulatory systems, the inner space and flow channel network are distributed hierarchically as arteries, veins, capillaries and ventricles. A conceptual configuration of the bionic system is presented, and its numerical model is established to demonstrate the flow and heat transfer phenomena. The encapsulated PCM that is used in this study is fabricated and parameters related have been measured by experiments. A numerical model of a 3D continuous PCM bed is established to help research the flow of HTF through the surfaces of PCM particles and the heat transfer between them. Then, a model of a simplified bionic device is developed where the PCM region is set as a porous domain. The results show the flow and temperature fields are distributed uniformly, along with a much smaller global pressure drop. By allocating the thermal load on cascaded layers with stepwise PCMs, a more homogeneous global temperature difference can be achieved.

EEG Signal Classification of Motor Imagery Right and Left Hand using Common Spatial Pattern and Multilayer Perceptron Back Propagation

The number of people with disabilities is increasing, so it requires bionic devices to replace human motor functions. Brain-Computer Interface (BCI) can be a tool for the bionic device to communicate with the brain. Signal brain or Electroencephalogram (EEG) signal need to classify to drive the corresponding bionic device. This research goal is to classify the imagination of the right and left-hand movements based on the EEG signal. The system design in this research consists of EEG channel selection using Finite Impulse Response (FIR) filter, feature extraction using Common Spatial Pattern (CSP), and classification using Multilayer Perceptron Back Propagation (MLP-BP). The data used a secondary dataset from BCI Competition IV (2b) with 9 research subjects. The research scenario is carried out by trying to use several variations in the number of hidden layer nodes on each EEG channel. Based on the test, the best accuracy for MLP-BP is 68.7% using 24 nodes in the alpha channel.