Microrobots powered by an external magnetic field could be used for sophisticated medical applications such as cell treatment,micromanipulation,and noninvasive surgery inside the body.Untethered microrobot application...Microrobots powered by an external magnetic field could be used for sophisticated medical applications such as cell treatment,micromanipulation,and noninvasive surgery inside the body.Untethered microrobot applications can benefit from haptic technology and telecommunication,enabling telemedical micro-manipulation.Users can manipulate the microrobots with haptic feedback by interacting with the robot operating system remotely in such applications.Artificially created haptic forces based on wirelessly transmitted data and model-based guidance can aid human operators with haptic sensations while manipulating microrobots.The system presented here includes a haptic device and a magnetic tweezer system linked together using a network-based teleoperation method with motion models in fluids.The magnetic microrobots can be controlled remotely,and the haptic interactions with the remote environment can be felt in real time.A time-domain passivity controller is applied to overcome network delay and ensure stability of communication.This study develops and tests a motion model for microrobots and evaluates two image-based 3D tracking algorithms to improve tracking accuracy in various Newtonian fluids.Additionally,it demonstrates that microrobots can group together to transport multiple larger objects,move through microfluidic channels for detailed tasks,and use a novel method for disassembly,greatly expanding their range of use in microscale operations.Remote medical treatment in multiple locations,remote delivery of medication without the need for physical penetration of the skin,and remotely controlled cell manipulations are some of the possible uses of the proposed technology.展开更多
Bio-inspired magnetic helical microrobots have great potential for biomedical and micromanipulation applications. Precise interaction with objects in liquid environments is an important prerequisite and challenge for ...Bio-inspired magnetic helical microrobots have great potential for biomedical and micromanipulation applications. Precise interaction with objects in liquid environments is an important prerequisite and challenge for helical microrobots to perform various tasks. In this study, an automatic control method is proposed to realize the axial docking of helical microrobots with arbitrarily placed cylindrical objects in liquid environments. The docking process is divided into ascent, approach, alignment, and insertion stages. First, a 3D docking path is planned according to the positions and orientations of the microrobot and the target object. Second, a steering-based 3D path-following controller guides the helical microrobot to rise away from the container bottom and approach the target along the path. Third, based on path design with gravity compensation and steering output limits, alignment of position and orientation can be accomplished simultaneously. Finally, the helical microrobot completes the docking under the rotating magnetic field along the target orientation. Experiments verified the automatic docking of the helical microrobot with static targets, including connecting with micro-shafts and inserting into micro-tubes. The object grasping of a reconfigurable helical microrobot aided by 3D automatic docking was also demonstrated. This method enables precise docking of helical microrobots with objects, which might be used for capture and sampling, in vivo navigation control, and functional assembly of microrobots.展开更多
Disorders of the musculoskeletal system are the major contributors to the global burden of disease and current treatments show limited efficacy.Patients often suffer chronic pain and might eventually have to undergo e...Disorders of the musculoskeletal system are the major contributors to the global burden of disease and current treatments show limited efficacy.Patients often suffer chronic pain and might eventually have to undergo end-stage surgery.Therefore,future treatments should focus on early detection and intervention of regional lesions.Microrobots have been gradually used in organisms due to their advantages of intelligent,precise and minimally invasive targeted delivery.Through the combination of control and imaging systems,microrobots with good biosafety can be delivered to the desired area for treatment.In the musculoskeletal system,microrobots are mainly utilized to transport stem cells/drugs or to remove hazardous substances from the body.Compared to traditional biomaterial and tissue engineering strategies,active motion improves the efficiency and penetration of local targeting of cells/drugs.This review discusses the frontier applications of microrobotic systems in different tissues of the musculoskeletal system.We summarize the challenges and barriers that hinder clinical translation by evaluating the characteristics of different microrobots and finally point out the future direction of microrobots in the musculoskeletal system.展开更多
Inspired by the fast,agile movements of insects,we present a 1.9 g,4.5 cm in length,piezoelectrically driven,quadrupedal microrobot.This microrobot uses a novel spatial parallel mechanism as its hip joint,which consis...Inspired by the fast,agile movements of insects,we present a 1.9 g,4.5 cm in length,piezoelectrically driven,quadrupedal microrobot.This microrobot uses a novel spatial parallel mechanism as its hip joint,which consists of two spatially orthogonal slider-crank linkages.This mechanism maps two inputs of two independent actuators to the decoupled swing and lift outputs of a leg,and each leg can produce the closed trajectories in the sagittal plane necessary for robot motion.Moreover,the kinematics of the transmission are analyzed,and the parameters of the flexure hinges are designed based on geometrical constraints and yield conditions.The hip joints,legs and exoskeletons are integrated into a five-layer standard laminate for monolithic fabrication which is composed of two layers of carbon fiber,two layers of acrylic adhesive and a polyimide film.The measured output force(15.97 mN)of each leg is enough to carry half of the robot’s weight,which is necessary for the robot to move successfully.It has been proven that the robot can successfully perform forward and turning motions.Compared to the microrobot fabricated with discrete components,the monolithically fabricated microrobot is more capable of maintaining the original direction of locomotion when driven by a forward signal and has a greater speed,whose maximum speed is 25.05 cm/s.展开更多
For a significant duration,enhancing the efficacy of cancer therapy has remained a critical concern.Magnetotactic bacteria(MTB),often likened to micro-robots,hold substantial promise as a drug delivery system.MTB,clas...For a significant duration,enhancing the efficacy of cancer therapy has remained a critical concern.Magnetotactic bacteria(MTB),often likened to micro-robots,hold substantial promise as a drug delivery system.MTB,classified as anaerobic,aquatic,and gram-negative microorganisms,exhibit remarkable motility and precise control over their internal biomineralization processes.This unique ability results in the formation of magnetic nanoparticles arranged along filamentous structures in a catenary fashion,enclosed within a membrane.These bacteria possess distinctive biochemical properties that facilitate their precise positioning within complex environments.By harnessing these biochemical attributes,MTB could potentially offer substantial advantages in the realm of cancer therapy.This article reviews the drug delivery capabilities of MTB in tumor treatment and explores various applications based on their inherent properties.The objective is to provide a comprehensive understanding of MTB-driven drug delivery and stimulate innovative insights in this field.展开更多
This study focuses on exploring the complex dynamical behaviors of a magnetic microrobot in a random environment.The purpose is to reveal the mechanism of influence of random disturbance on microrobot dynamics.This pa...This study focuses on exploring the complex dynamical behaviors of a magnetic microrobot in a random environment.The purpose is to reveal the mechanism of influence of random disturbance on microrobot dynamics.This paper establishes stochastic dynamic models for the microrobot before and after deformation,considering the influence of Gaussian white noise.The system responses are analyzed via steady-state probability density functions and first deformation time.The effects of different magnetic field strengths and fluid viscosities on the movement speed and angular velocity of the microrobot are studied.The results indicate that random disturbances can cause deformation of microrobots in advance compared to the deterministic case.This work contributes to the design and motion control of microrobots and enhances the theoretical foundation of microrobots.展开更多
In order to develop a new type of fish-like microrobot with swimming, walking, and floating motions, in our past research, we developed a hybrid microrobot actuated by ionic conducting polymer film （ICPF） actuators....In order to develop a new type of fish-like microrobot with swimming, walking, and floating motions, in our past research, we developed a hybrid microrobot actuated by ionic conducting polymer film （ICPF） actuators. But the microrobot had some problems in walking and floating motions. In this paper, we propose a concept of hybrid microrobot （see Fig. 1）. The microrobot is actuated by a pair of caudal fins, a base with legs and an array of artificial swim bladders. We have developed a prototype of the base with legs and one artificial swim bladder, respectively, and carried out experiments for evaluating their characteristics. Experimental results show the base with legs can realize walking speed of 6 mm/s and rotating speed of 7.1 degrees/s respectively, and the prototype of the artificial swim bladder has a maximum floatage of 2.6 mN. The experimental results also indicate that the microrobot has some advantages, such as walking motion with 2 degrees of freedom, the walking ability on rough surface （sand paper）, the controllable floatage, etc. This kind of fish-like microrobot is expected for industrial and medical applications.展开更多
It is our target to develop underwater microrobots for medical and industrial applications. This kind of underwater microrobots should have the characteristics of flexibility, good response and safety. Its structure s...It is our target to develop underwater microrobots for medical and industrial applications. This kind of underwater microrobots should have the characteristics of flexibility, good response and safety. Its structure should be simple and it can be driven by low voltage and produces no pollution or noise. The low actuating voltage and quick bending responses of Ionic Conducting Polymer Film （ICPF） are considered very useful and attractive for constructing various types of actuators and sensors. In this paper, we will first study the characteristics of the ICPF actuator used in underwater microrobot to realize swimming and walking. Then, we propose a new prototype model of underwater swimming microrobot utilizing only one piece of ICPF as the servo actuator. Through theoretic analysis, the motion mechanism of the microrobot is illustrated. It can swim forward and vertically. The relationships between moving speed and signal voltage amplitude and signal frequency is obtained after experimental study. Lastly, we present a novel underwater crab-like walking microrobot named crabliker-1. It has eight legs, and each leg is made up of two pieces of ICPF. Three sample processes of the octopod gait are proposed with a new analyzing method. The experimental results indicate that the crab-like underwater microrobot can perform transverse and rotation movement when the legs of the crab collaborate.展开更多
Hydrogels with stimuli-responsive capabilities are gaining more and more attention nowadays with prospective applications in biomedical engineering,bioelectronics,microrobot,etc.We develop a photothermal responsive hy...Hydrogels with stimuli-responsive capabilities are gaining more and more attention nowadays with prospective applications in biomedical engineering,bioelectronics,microrobot,etc.We develop a photothermal responsive hydrogel based on N-isopropylacrylamide that achieved a fast and reversible deformation manipulated only by near-infrared(NIR)light.The hydrogel was fabricated by the projection micro stereolithography based 3D printing technique,which can rapidly prototype complex 3D structures.Furthermore,with the variation of the grayscale while manufacturing the hydrogel,the deformation of the hydrogel structure can be freely tuned within a few seconds by losing and absorbing water through adjusting the intensity and the irradiation direction of the NIR light,showing a potential application in ultra-fast object grabbing and transportation.The present study provides a new method for designing ultrafast photothermal responsive hydrogel based microrobot working in water.展开更多
This paper presents the moving mechanism of a high-speed insect-scale microrobot via electromagnetically induced vibration of two simply supported beams.The microrobot,which has a body length of 12.3 mm and a total ma...This paper presents the moving mechanism of a high-speed insect-scale microrobot via electromagnetically induced vibration of two simply supported beams.The microrobot,which has a body length of 12.3 mm and a total mass of 137 mg,can achieve reciprocating lift motion of forelegs without any intermediate linkage mechanisms due to the design of an obliquely upward body tilt angle.The gait study shows that the body tilt angle prevents the forelegs from swinging backward when the feet contact the ground,which results in a forward friction force applied on the feet.During forward movement,the microrobot utilizes the elastic deformation of the simply supported beams as driving force to slide forward and its forelegs and rear legs work as pivots alternatively in a way similar to the movement of soft worms.The gait analysis also indicates that the moving direction of the microrobot is determined by whether its body tilt angle is obliquely upward or downward,and its moving speed is also related to the body tilt angle and as well as the body height.Under an applied AC voltage of 4 V,the microrobot can achieve a moving speed at 23.2 cm s1(18.9 body lengths per second),which is comparable to the fastest speed(20 cm s-1 or 20 body lengths per second)among the published insect-scale microrobots.The high-speed locomotion performance of the microrobot validates the feasibility of the presented actuation scheme and moving mechanism.展开更多
This paper presents the formulation and practical implementation of positioning methodologies that compensate for the nonholonomic constraints of a mobile microrobot that is driven by two vibrating direct current(DC) ...This paper presents the formulation and practical implementation of positioning methodologies that compensate for the nonholonomic constraints of a mobile microrobot that is driven by two vibrating direct current(DC) micromotors. The open-loop and closed-loop approaches described here add the capability for net sidewise displacements of the microrobotic platform. A displacement is achieved by the execution of a number of repeating steps that depend on the desired displacement, the speed of the micromotors, and the elapsed time. Simulation and experimental results verified the performance of the proposed methodologies.展开更多
A simple autonomous docking method based on infrared sensors for mobile self-reconfigurable relay microrobots is proposed in the paper.The IR guidance system composed of an IR receiver and four IR emitters is designed...A simple autonomous docking method based on infrared sensors for mobile self-reconfigurable relay microrobots is proposed in the paper.The IR guidance system composed of an IR receiver and four IR emitters is designed,analyzed and developed.The autonomous docking control method based on centering alignment and dynamic motion planning is adopted so that it has high efficiency and reliability.Two basic microrobot prototypes are developed,and related docking experiments are done to verify the feasibility of the approach.展开更多
Micro/nanorobots based on immune cells show great potential for addressing challenging biological and biomedical conditions.However,their powerful innate immune functions,particularly the phagocytosis capabilities,rem...Micro/nanorobots based on immune cells show great potential for addressing challenging biological and biomedical conditions.However,their powerful innate immune functions,particularly the phagocytosis capabilities,remain a big challenge to fully leverage with the current designs of immune cell-based microrobots.Herein,we report a lightpowered phagocytic macrophage microrobot(phagobot),which is capable of robotic navigation toward specific foreign bio-threats and executing precise phagocytosis of these targeted entities under light control.Without genetic modification or nanoengineering of macrophages,the phagobot’s“wake-up”program is achieved through direct activation of a resting-state macrophage by a tightly focused near-infrared(NIR)light beam.The phagobot exhibits robotic steering and directional navigation controlled by optical manipulation of the extended pseudopodia within the activated macrophage.It can further execute targeted phagocytic clearance tasks via engulfing various foreign bio-threats,including nanoplastics,microbials,and cancer cell debris.Notably,the phagobot can be constructed in a living larval zebrafish through optical activation and manipulation of the endogenous macrophage,which also exhibits controllable navigation and targeted phagocytic capabilities in vivo.With the intrinsic immune functions of macrophages,our light-powered phagobot represents a novel form of intelligent immune cell-based microrobots,holding many new possibilities for precise immune regulation and treatment for immune-related diseases.展开更多
Bio-integrated microrobots(BIMs),which are fabricated with biofriendly materials,biological units(e.g.cells or biomolecules),or cell-material hybrids have emerged as a promising technology for minimally invasive biome...Bio-integrated microrobots(BIMs),which are fabricated with biofriendly materials,biological units(e.g.cells or biomolecules),or cell-material hybrids have emerged as a promising technology for minimally invasive biomedicine.The diminutive size and flexible structures enable BIMs to navigate within narrow,deep,and challenging-to-reach in vivo regions,performing biopsy,diagnostic,drug delivery,and therapeutic functions with minimal invasiveness.However,the clinical deployment of BIMs is a highly orchestrated task that requires consideration of material properties,structural design,locomotion,observation,therapeutic outcomes,and side effects on cells and tissues,etc.In this review,we review and discuss the latest advances in the biointegrated microrobot domain,evaluating various methods associated with materials,fabrication,actuation,and the implementation of biomedical functions in BIMs.By comparing the advantages and shortcomings of these techniques,this review highlights the challenges and future trends in highly intelligent bio-integrated microrobots,which have huge potential in minimally invasive biomedicine.展开更多
Bacterial biofilms can make traditional antibiotics impenetrable and even promote the development of antibiotic-resistant strains.Therefore,non-antibiotic strategies to effectively penetrate and eradicate the formed b...Bacterial biofilms can make traditional antibiotics impenetrable and even promote the development of antibiotic-resistant strains.Therefore,non-antibiotic strategies to effectively penetrate and eradicate the formed biofilms are urgently needed.Here,we demonstrate the development of selfpropelled biohybrid microrobots that can enhance the degradation and penetration effects for Pseudomonas aeruginosa biofilms in minimally invasive strategy.The biohybrid microrobots(CR@Alg)are constructed by surface modification of Chlamydomonas reinhardtii(CR)microalgae with alginate lyase(Alg)via biological orthogonal reaction.By degrading the biofilm components,the number of CR@Alg microrobots with fast-moving capability penetrating the biofilm increases by around 2.4-fold compared to that of microalgae.Massive reactive oxygen species are subsequently generated under laser irradiation due to the presence of chlorophyll,inherent photosensitizers of microalgae,thus triggering photodynamic therapy(PDT)to combat bacteria.Our algae-based microrobots with superior biocompatibility eliminate biofilm-infections efficiently and tend to suppress the inflammatory response in vivo,showing huge promise for the active treatment of biofilm-associated infections.展开更多
Magnetic microrobots,given their unique characteristics,hold great potential in biomedical applications such as targeted therapy and microscale operations and are receiving widespread attention.Research on the autonom...Magnetic microrobots,given their unique characteristics,hold great potential in biomedical applications such as targeted therapy and microscale operations and are receiving widespread attention.Research on the autonomous navigation of magnetic microrobots is highly focused,as it is an essential prerequisite for achieving functions such as targeted delivery in medical settings.The success of autonomous navigation determines the level of intelligence and precision in the motion of magnetic microrobots.However,uncertainties stemming from environmental changes and time-varying disturbances in electromagnetic systems adversely affect the control accuracy of magnetic microrobots.Additionally,the random appearance of dynamic obstacles along expected trajectories challenges their autonomous navigation.In this study,we demonstrate a method for the exact autonomous navigation of magnetic microrobots in fluid environments,successfully avoiding dynamic obstacles that suddenly appear in predefined trajectories.Improved versions of the A^(*) algorithm and dynamic window approach are integrated as path planners,that can generate smooth and collision-free trajectories that adhere to kinematic constraints in fluid environments with dynamic obstacles.A learning-based model predictive control strategy is employed,where radial basis function neural networks are used to effectively predict and compensate for fluid disturbances and inevitable errors introduced by electromagnetic system coupling,thereby ensuring the control accuracy of the magnetic microrobot in a flowing environment.Experiments in a constructed microfluidic environment validate the effectiveness of our navigation approach in motion control,autonomous navigation,and replanning,with an average error of less than 8%of the body length of the microrobot.展开更多
Manipulating cells at a small scale is widely acknowledged as a complex and challenging task,especially when it comes to cell grasping and transportation.Various precise methods have been developed to remotely control...Manipulating cells at a small scale is widely acknowledged as a complex and challenging task,especially when it comes to cell grasping and transportation.Various precise methods have been developed to remotely control the movement of microrobots.However,the manipulation of micro-objects necessitates the use of end-effectors.This paper presents a study on the control of movement and grasping operations of a magnetic microrobot,utilizing only 3 pairs of electromagnetic coils.A specially designed microgripper is employed on the microrobot for efficient cell grasping and transportation.To ensure precise grasping,a bending deformation model of the microgripper is formulated and subsequently validated.To achieve precise and reliable transportation of cells to specific positions,an approach that combines an extended Kalman filter with a model predictive control method is adopted to accomplish the trajectory tracking task.Through experiments,we observe that by applying the proposed control strategy,the mean absolute error of path tracking is found to be less than 0.155 mm.Remarkably,this value accounts for only 1.55% of the microrobot’s size,demonstrating the efficacy and accuracy of our control strategy.Furthermore,an experiment involving the grasping and transportation of a zebrafish embryonic cell(diameter:800μm)is successfully conducted.The results of this experiment not only validate the precision and effectiveness of the proposed microrobot and its associated models but also highlight its tremendous potential for cell manipulation in vitro and in vivo.展开更多
Metal-organic frameworks(MOFs)hold significant potential as vehicles for drug delivery due to their expansive specific surface area,biocompatibility,and versatile attributes.Concurrently,magnetically actuated micro/na...Metal-organic frameworks(MOFs)hold significant potential as vehicles for drug delivery due to their expansive specific surface area,biocompatibility,and versatile attributes.Concurrently,magnetically actuated micro/nano-robots(MNRs)offer distinct advantages,such as untethered and precise manipulation.The fusion of these technologies presents a promising avenue for achieving non-invasive targeted drug delivery.Here,we report a MOF-based magnetic microrobot swarm(MMRS)for targeted therapy.Our approach overcomes limitations associated with a single MNR,including limited drug loading and the risk of loss during manipulation.We select Zeolitic Imidazolate Framework-8(ZIF-8)as the drug vehicle for its superior loading potential and p H-sensitive decomposition.Our design incorporates magnetic responsive components into the one-pot synthesis of Fe@ZIF-8,enabling collective behaviors under actuation.Tuning the yaw angle of alternating magnetic fields and nanoparticles'amount,the MMRSs with controllable size achieve instantaneous transformation among different configurations,including vortex-like swarms,chain-like swarms,and elliptical swarms,facilitating adaptation to environmental variations.Transported to the subcutaneous T24 tumor site,the MMRSs with encapsulated doxorubicin(DOX)automatically degrade and release the drug,leading to a dramatic reduction of the tumor in vivo.Our investigation signifies a significant advancement in the integration of biodegradable MOFs into microrobot swarms,ushering in new avenues for accurate and non-invasive targeted drug delivery.展开更多
Oral administration is the most simple, noninvasive, convenient treatment. With the increasing demands on thetargeted drug delivery, the traditional oral treatment now is facing some challenges: 1) biologics how toimp...Oral administration is the most simple, noninvasive, convenient treatment. With the increasing demands on thetargeted drug delivery, the traditional oral treatment now is facing some challenges: 1) biologics how toimplement the oral treatment and ensure the bioavailability is not lower than the subcutaneous injections;2)How to achieve targeted therapy of some drugs in the gastrointestinal tract? Based on these two issues, drugdelivery microrobots have shown great application prospect in oral drug delivery due to their characteristics offlexible locomotion or driven ability. Therefore, this paper summarizes various drug delivery microrobotsdeveloped in recent years and divides them into four categories according to different driving modes: magneticcontrolleddrug delivery microrobots, anchored drug delivery microrobots, self-propelled drug delivery microrobotsand biohybrid drug delivery microrobots. As oral drug delivery microrobots involve disciplines such asmaterials science, mechanical engineering, medicine, and control systems, this paper begins by introducing thegastrointestinal barriers that oral drug delivery must overcome. Subsequently, it provides an overview of typicalmaterials involved in the design process of oral drug delivery microrobots. To enhance readers’ understanding ofthe working principles and design process of oral drug delivery microrobots, we present a guideline for designingsuch microrobots. Furthermore, the current development status of various types of oral drug delivery microrobotsis reviewed, summarizing their respective advantages and limitations. Finally, considering the significantconcerns regarding safety and clinical translation, we discuss the challenges and prospections of clinical translationfor various oral drug delivery microrobots presented in this paper, providing corresponding suggestions foraddressing some existing challenges.展开更多
基金supported by National Science Foundation Grant No.2123824.
文摘Microrobots powered by an external magnetic field could be used for sophisticated medical applications such as cell treatment,micromanipulation,and noninvasive surgery inside the body.Untethered microrobot applications can benefit from haptic technology and telecommunication,enabling telemedical micro-manipulation.Users can manipulate the microrobots with haptic feedback by interacting with the robot operating system remotely in such applications.Artificially created haptic forces based on wirelessly transmitted data and model-based guidance can aid human operators with haptic sensations while manipulating microrobots.The system presented here includes a haptic device and a magnetic tweezer system linked together using a network-based teleoperation method with motion models in fluids.The magnetic microrobots can be controlled remotely,and the haptic interactions with the remote environment can be felt in real time.A time-domain passivity controller is applied to overcome network delay and ensure stability of communication.This study develops and tests a motion model for microrobots and evaluates two image-based 3D tracking algorithms to improve tracking accuracy in various Newtonian fluids.Additionally,it demonstrates that microrobots can group together to transport multiple larger objects,move through microfluidic channels for detailed tasks,and use a novel method for disassembly,greatly expanding their range of use in microscale operations.Remote medical treatment in multiple locations,remote delivery of medication without the need for physical penetration of the skin,and remotely controlled cell manipulations are some of the possible uses of the proposed technology.
基金supported by the National Natural Science Foundation of China(No.62273117)Pre-research Task(No.SKLRS202418B)of State Key Laboratory of Robotics and Systems(HIT).
文摘Bio-inspired magnetic helical microrobots have great potential for biomedical and micromanipulation applications. Precise interaction with objects in liquid environments is an important prerequisite and challenge for helical microrobots to perform various tasks. In this study, an automatic control method is proposed to realize the axial docking of helical microrobots with arbitrarily placed cylindrical objects in liquid environments. The docking process is divided into ascent, approach, alignment, and insertion stages. First, a 3D docking path is planned according to the positions and orientations of the microrobot and the target object. Second, a steering-based 3D path-following controller guides the helical microrobot to rise away from the container bottom and approach the target along the path. Third, based on path design with gravity compensation and steering output limits, alignment of position and orientation can be accomplished simultaneously. Finally, the helical microrobot completes the docking under the rotating magnetic field along the target orientation. Experiments verified the automatic docking of the helical microrobot with static targets, including connecting with micro-shafts and inserting into micro-tubes. The object grasping of a reconfigurable helical microrobot aided by 3D automatic docking was also demonstrated. This method enables precise docking of helical microrobots with objects, which might be used for capture and sampling, in vivo navigation control, and functional assembly of microrobots.
基金supported by the National Natural Science Foundation of China(No.81572187,No.81871812 and No.52205590)the Natural Science Foundation of Jiangsu Province(No.BK20220834)+1 种基金project supported by Ruihua Charity Foundation(YL20220525)the Start-up Research Fund of Southeast University(No.RF1028623098).
文摘Disorders of the musculoskeletal system are the major contributors to the global burden of disease and current treatments show limited efficacy.Patients often suffer chronic pain and might eventually have to undergo end-stage surgery.Therefore,future treatments should focus on early detection and intervention of regional lesions.Microrobots have been gradually used in organisms due to their advantages of intelligent,precise and minimally invasive targeted delivery.Through the combination of control and imaging systems,microrobots with good biosafety can be delivered to the desired area for treatment.In the musculoskeletal system,microrobots are mainly utilized to transport stem cells/drugs or to remove hazardous substances from the body.Compared to traditional biomaterial and tissue engineering strategies,active motion improves the efficiency and penetration of local targeting of cells/drugs.This review discusses the frontier applications of microrobotic systems in different tissues of the musculoskeletal system.We summarize the challenges and barriers that hinder clinical translation by evaluating the characteristics of different microrobots and finally point out the future direction of microrobots in the musculoskeletal system.
基金supported by the Shanghai professional technology service platform under Grant 19DZ2291103.
文摘Inspired by the fast,agile movements of insects,we present a 1.9 g,4.5 cm in length,piezoelectrically driven,quadrupedal microrobot.This microrobot uses a novel spatial parallel mechanism as its hip joint,which consists of two spatially orthogonal slider-crank linkages.This mechanism maps two inputs of two independent actuators to the decoupled swing and lift outputs of a leg,and each leg can produce the closed trajectories in the sagittal plane necessary for robot motion.Moreover,the kinematics of the transmission are analyzed,and the parameters of the flexure hinges are designed based on geometrical constraints and yield conditions.The hip joints,legs and exoskeletons are integrated into a five-layer standard laminate for monolithic fabrication which is composed of two layers of carbon fiber,two layers of acrylic adhesive and a polyimide film.The measured output force(15.97 mN)of each leg is enough to carry half of the robot’s weight,which is necessary for the robot to move successfully.It has been proven that the robot can successfully perform forward and turning motions.Compared to the microrobot fabricated with discrete components,the monolithically fabricated microrobot is more capable of maintaining the original direction of locomotion when driven by a forward signal and has a greater speed,whose maximum speed is 25.05 cm/s.
基金supported by the National Natural Science Foundation of China(No.3190110313 to K.Ma)Special Foundation of President of the Chinese Academy of Sciences(No.YZJJ2022QN_(4)4)+2 种基金HFIPS Director’s Fund(Nos.E16CWK123X1YZJJQY202201)the Heye Health Technology Chong Ming Project(No.HYCMP-2022012 to Y.Wang)。
文摘For a significant duration,enhancing the efficacy of cancer therapy has remained a critical concern.Magnetotactic bacteria(MTB),often likened to micro-robots,hold substantial promise as a drug delivery system.MTB,classified as anaerobic,aquatic,and gram-negative microorganisms,exhibit remarkable motility and precise control over their internal biomineralization processes.This unique ability results in the formation of magnetic nanoparticles arranged along filamentous structures in a catenary fashion,enclosed within a membrane.These bacteria possess distinctive biochemical properties that facilitate their precise positioning within complex environments.By harnessing these biochemical attributes,MTB could potentially offer substantial advantages in the realm of cancer therapy.This article reviews the drug delivery capabilities of MTB in tumor treatment and explores various applications based on their inherent properties.The objective is to provide a comprehensive understanding of MTB-driven drug delivery and stimulate innovative insights in this field.
基金supported by the National Nature Science Foundation of China(Grant Nos.12072264 and 12272296)the Key International(Regional)Joint Research Program of the National Science Foundation of China(Grant No.12120101002)+1 种基金the National Science Foundation of Chongqing,China(Grant No.cstc2021jcyj-msxm X0738)the National Science Foundation of Guangdong Province,China(Grant No.2023A1515012329)。
文摘This study focuses on exploring the complex dynamical behaviors of a magnetic microrobot in a random environment.The purpose is to reveal the mechanism of influence of random disturbance on microrobot dynamics.This paper establishes stochastic dynamic models for the microrobot before and after deformation,considering the influence of Gaussian white noise.The system responses are analyzed via steady-state probability density functions and first deformation time.The effects of different magnetic field strengths and fluid viscosities on the movement speed and angular velocity of the microrobot are studied.The results indicate that random disturbances can cause deformation of microrobots in advance compared to the deterministic case.This work contributes to the design and motion control of microrobots and enhances the theoretical foundation of microrobots.
文摘In order to develop a new type of fish-like microrobot with swimming, walking, and floating motions, in our past research, we developed a hybrid microrobot actuated by ionic conducting polymer film （ICPF） actuators. But the microrobot had some problems in walking and floating motions. In this paper, we propose a concept of hybrid microrobot （see Fig. 1）. The microrobot is actuated by a pair of caudal fins, a base with legs and an array of artificial swim bladders. We have developed a prototype of the base with legs and one artificial swim bladder, respectively, and carried out experiments for evaluating their characteristics. Experimental results show the base with legs can realize walking speed of 6 mm/s and rotating speed of 7.1 degrees/s respectively, and the prototype of the artificial swim bladder has a maximum floatage of 2.6 mN. The experimental results also indicate that the microrobot has some advantages, such as walking motion with 2 degrees of freedom, the walking ability on rough surface （sand paper）, the controllable floatage, etc. This kind of fish-like microrobot is expected for industrial and medical applications.
文摘It is our target to develop underwater microrobots for medical and industrial applications. This kind of underwater microrobots should have the characteristics of flexibility, good response and safety. Its structure should be simple and it can be driven by low voltage and produces no pollution or noise. The low actuating voltage and quick bending responses of Ionic Conducting Polymer Film （ICPF） are considered very useful and attractive for constructing various types of actuators and sensors. In this paper, we will first study the characteristics of the ICPF actuator used in underwater microrobot to realize swimming and walking. Then, we propose a new prototype model of underwater swimming microrobot utilizing only one piece of ICPF as the servo actuator. Through theoretic analysis, the motion mechanism of the microrobot is illustrated. It can swim forward and vertically. The relationships between moving speed and signal voltage amplitude and signal frequency is obtained after experimental study. Lastly, we present a novel underwater crab-like walking microrobot named crabliker-1. It has eight legs, and each leg is made up of two pieces of ICPF. Three sample processes of the octopod gait are proposed with a new analyzing method. The experimental results indicate that the crab-like underwater microrobot can perform transverse and rotation movement when the legs of the crab collaborate.
基金the National Natural Science Foundation of China(52006056)the Key-Area Research and Development Program of Guangdong Province(2020B090923003)the Natural Science Foundation of Hunan through Grant No.2020JJ3012。
文摘Hydrogels with stimuli-responsive capabilities are gaining more and more attention nowadays with prospective applications in biomedical engineering,bioelectronics,microrobot,etc.We develop a photothermal responsive hydrogel based on N-isopropylacrylamide that achieved a fast and reversible deformation manipulated only by near-infrared(NIR)light.The hydrogel was fabricated by the projection micro stereolithography based 3D printing technique,which can rapidly prototype complex 3D structures.Furthermore,with the variation of the grayscale while manufacturing the hydrogel,the deformation of the hydrogel structure can be freely tuned within a few seconds by losing and absorbing water through adjusting the intensity and the irradiation direction of the NIR light,showing a potential application in ultra-fast object grabbing and transportation.The present study provides a new method for designing ultrafast photothermal responsive hydrogel based microrobot working in water.
基金This work is supported by the National Natural Science Foundation of China(Grant No.12002017)China Postdoctoral Science Foundation(Grant No.2019M650441)the 111 Project(Grant No.B08009).
文摘This paper presents the moving mechanism of a high-speed insect-scale microrobot via electromagnetically induced vibration of two simply supported beams.The microrobot,which has a body length of 12.3 mm and a total mass of 137 mg,can achieve reciprocating lift motion of forelegs without any intermediate linkage mechanisms due to the design of an obliquely upward body tilt angle.The gait study shows that the body tilt angle prevents the forelegs from swinging backward when the feet contact the ground,which results in a forward friction force applied on the feet.During forward movement,the microrobot utilizes the elastic deformation of the simply supported beams as driving force to slide forward and its forelegs and rear legs work as pivots alternatively in a way similar to the movement of soft worms.The gait analysis also indicates that the moving direction of the microrobot is determined by whether its body tilt angle is obliquely upward or downward,and its moving speed is also related to the body tilt angle and as well as the body height.Under an applied AC voltage of 4 V,the microrobot can achieve a moving speed at 23.2 cm s1(18.9 body lengths per second),which is comparable to the fastest speed(20 cm s-1 or 20 body lengths per second)among the published insect-scale microrobots.The high-speed locomotion performance of the microrobot validates the feasibility of the presented actuation scheme and moving mechanism.
基金supported in part by the National Science Foundation(IIS1318638 and IIS1426752)the Shenzhen Science and Technology Project(ZDSY20120617113312191)
文摘This paper presents the formulation and practical implementation of positioning methodologies that compensate for the nonholonomic constraints of a mobile microrobot that is driven by two vibrating direct current(DC) micromotors. The open-loop and closed-loop approaches described here add the capability for net sidewise displacements of the microrobotic platform. A displacement is achieved by the execution of a number of repeating steps that depend on the desired displacement, the speed of the micromotors, and the elapsed time. Simulation and experimental results verified the performance of the proposed methodologies.
基金Supported by the National High Technology Research and Development Programme of China(No.2007AA04Z340)
文摘A simple autonomous docking method based on infrared sensors for mobile self-reconfigurable relay microrobots is proposed in the paper.The IR guidance system composed of an IR receiver and four IR emitters is designed,analyzed and developed.The autonomous docking control method based on centering alignment and dynamic motion planning is adopted so that it has high efficiency and reliability.Two basic microrobot prototypes are developed,and related docking experiments are done to verify the feasibility of the approach.
基金the National Natural Science Foundation of China(12374286,32271405,and 12204196)Guangdong Basic and Applied Basic Research Foundation(2024A1515012514,2022B1515120012)+1 种基金Science and Technology Program of Guangzhou(2024A04J6319)the Fundamental Research Funds for the Central Universities(21623112,21624217).
文摘Micro/nanorobots based on immune cells show great potential for addressing challenging biological and biomedical conditions.However,their powerful innate immune functions,particularly the phagocytosis capabilities,remain a big challenge to fully leverage with the current designs of immune cell-based microrobots.Herein,we report a lightpowered phagocytic macrophage microrobot(phagobot),which is capable of robotic navigation toward specific foreign bio-threats and executing precise phagocytosis of these targeted entities under light control.Without genetic modification or nanoengineering of macrophages,the phagobot’s“wake-up”program is achieved through direct activation of a resting-state macrophage by a tightly focused near-infrared(NIR)light beam.The phagobot exhibits robotic steering and directional navigation controlled by optical manipulation of the extended pseudopodia within the activated macrophage.It can further execute targeted phagocytic clearance tasks via engulfing various foreign bio-threats,including nanoplastics,microbials,and cancer cell debris.Notably,the phagobot can be constructed in a living larval zebrafish through optical activation and manipulation of the endogenous macrophage,which also exhibits controllable navigation and targeted phagocytic capabilities in vivo.With the intrinsic immune functions of macrophages,our light-powered phagobot represents a novel form of intelligent immune cell-based microrobots,holding many new possibilities for precise immune regulation and treatment for immune-related diseases.
基金funded by the National Natural Science Foundation of China under Grant Nos.62222305,62403056,62088101the Science and Technology Innovation Program of Beijing Institute of Technology under Grant 2024CX06008the Postdoctoral Fellowship Program of CPSF under Grant BX20230459.
文摘Bio-integrated microrobots(BIMs),which are fabricated with biofriendly materials,biological units(e.g.cells or biomolecules),or cell-material hybrids have emerged as a promising technology for minimally invasive biomedicine.The diminutive size and flexible structures enable BIMs to navigate within narrow,deep,and challenging-to-reach in vivo regions,performing biopsy,diagnostic,drug delivery,and therapeutic functions with minimal invasiveness.However,the clinical deployment of BIMs is a highly orchestrated task that requires consideration of material properties,structural design,locomotion,observation,therapeutic outcomes,and side effects on cells and tissues,etc.In this review,we review and discuss the latest advances in the biointegrated microrobot domain,evaluating various methods associated with materials,fabrication,actuation,and the implementation of biomedical functions in BIMs.By comparing the advantages and shortcomings of these techniques,this review highlights the challenges and future trends in highly intelligent bio-integrated microrobots,which have huge potential in minimally invasive biomedicine.
基金supported by National Key Research and Development Program of China(2022YFA1206900)Guangdong Basic and Applied Basic Research Foundation(2022A1515110659,China)National Natural Science Foundation of China(22175083 and 22375224).
文摘Bacterial biofilms can make traditional antibiotics impenetrable and even promote the development of antibiotic-resistant strains.Therefore,non-antibiotic strategies to effectively penetrate and eradicate the formed biofilms are urgently needed.Here,we demonstrate the development of selfpropelled biohybrid microrobots that can enhance the degradation and penetration effects for Pseudomonas aeruginosa biofilms in minimally invasive strategy.The biohybrid microrobots(CR@Alg)are constructed by surface modification of Chlamydomonas reinhardtii(CR)microalgae with alginate lyase(Alg)via biological orthogonal reaction.By degrading the biofilm components,the number of CR@Alg microrobots with fast-moving capability penetrating the biofilm increases by around 2.4-fold compared to that of microalgae.Massive reactive oxygen species are subsequently generated under laser irradiation due to the presence of chlorophyll,inherent photosensitizers of microalgae,thus triggering photodynamic therapy(PDT)to combat bacteria.Our algae-based microrobots with superior biocompatibility eliminate biofilm-infections efficiently and tend to suppress the inflammatory response in vivo,showing huge promise for the active treatment of biofilm-associated infections.
基金supported by the National Key R&D Program of China(Grant No.2023YFB4705600)the National Natural Science Foundation of China(Grant Nos.U23A20342,62273331,61925307,61821005)+1 种基金the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-036)the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘Magnetic microrobots,given their unique characteristics,hold great potential in biomedical applications such as targeted therapy and microscale operations and are receiving widespread attention.Research on the autonomous navigation of magnetic microrobots is highly focused,as it is an essential prerequisite for achieving functions such as targeted delivery in medical settings.The success of autonomous navigation determines the level of intelligence and precision in the motion of magnetic microrobots.However,uncertainties stemming from environmental changes and time-varying disturbances in electromagnetic systems adversely affect the control accuracy of magnetic microrobots.Additionally,the random appearance of dynamic obstacles along expected trajectories challenges their autonomous navigation.In this study,we demonstrate a method for the exact autonomous navigation of magnetic microrobots in fluid environments,successfully avoiding dynamic obstacles that suddenly appear in predefined trajectories.Improved versions of the A^(*) algorithm and dynamic window approach are integrated as path planners,that can generate smooth and collision-free trajectories that adhere to kinematic constraints in fluid environments with dynamic obstacles.A learning-based model predictive control strategy is employed,where radial basis function neural networks are used to effectively predict and compensate for fluid disturbances and inevitable errors introduced by electromagnetic system coupling,thereby ensuring the control accuracy of the magnetic microrobot in a flowing environment.Experiments in a constructed microfluidic environment validate the effectiveness of our navigation approach in motion control,autonomous navigation,and replanning,with an average error of less than 8%of the body length of the microrobot.
基金partially supported by the ZJU 100 Young Talent Program(Grant No.2019M650419).
文摘Manipulating cells at a small scale is widely acknowledged as a complex and challenging task,especially when it comes to cell grasping and transportation.Various precise methods have been developed to remotely control the movement of microrobots.However,the manipulation of micro-objects necessitates the use of end-effectors.This paper presents a study on the control of movement and grasping operations of a magnetic microrobot,utilizing only 3 pairs of electromagnetic coils.A specially designed microgripper is employed on the microrobot for efficient cell grasping and transportation.To ensure precise grasping,a bending deformation model of the microgripper is formulated and subsequently validated.To achieve precise and reliable transportation of cells to specific positions,an approach that combines an extended Kalman filter with a model predictive control method is adopted to accomplish the trajectory tracking task.Through experiments,we observe that by applying the proposed control strategy,the mean absolute error of path tracking is found to be less than 0.155 mm.Remarkably,this value accounts for only 1.55% of the microrobot’s size,demonstrating the efficacy and accuracy of our control strategy.Furthermore,an experiment involving the grasping and transportation of a zebrafish embryonic cell(diameter:800μm)is successfully conducted.The results of this experiment not only validate the precision and effectiveness of the proposed microrobot and its associated models but also highlight its tremendous potential for cell manipulation in vitro and in vivo.
基金supported by the National Natural Science Foundation of China(22275073,22005119,21731002,2197510422150004)the Guangdong Major Project of Basic and Applied Research(2019B030302009)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(2020A1515110404)the Guangzhou Basic and Applied Basic Research Foundation(2024A04J3597,202102020444)the Fundamental Research Funds for the Central Universities(21622409)。
文摘Metal-organic frameworks(MOFs)hold significant potential as vehicles for drug delivery due to their expansive specific surface area,biocompatibility,and versatile attributes.Concurrently,magnetically actuated micro/nano-robots(MNRs)offer distinct advantages,such as untethered and precise manipulation.The fusion of these technologies presents a promising avenue for achieving non-invasive targeted drug delivery.Here,we report a MOF-based magnetic microrobot swarm(MMRS)for targeted therapy.Our approach overcomes limitations associated with a single MNR,including limited drug loading and the risk of loss during manipulation.We select Zeolitic Imidazolate Framework-8(ZIF-8)as the drug vehicle for its superior loading potential and p H-sensitive decomposition.Our design incorporates magnetic responsive components into the one-pot synthesis of Fe@ZIF-8,enabling collective behaviors under actuation.Tuning the yaw angle of alternating magnetic fields and nanoparticles'amount,the MMRSs with controllable size achieve instantaneous transformation among different configurations,including vortex-like swarms,chain-like swarms,and elliptical swarms,facilitating adaptation to environmental variations.Transported to the subcutaneous T24 tumor site,the MMRSs with encapsulated doxorubicin(DOX)automatically degrade and release the drug,leading to a dramatic reduction of the tumor in vivo.Our investigation signifies a significant advancement in the integration of biodegradable MOFs into microrobot swarms,ushering in new avenues for accurate and non-invasive targeted drug delivery.
基金the funding from National Key Research and Development Program of China,China(No.2018YFA0703000)The National Natural Science Foundation of China No.52275294.
文摘Oral administration is the most simple, noninvasive, convenient treatment. With the increasing demands on thetargeted drug delivery, the traditional oral treatment now is facing some challenges: 1) biologics how toimplement the oral treatment and ensure the bioavailability is not lower than the subcutaneous injections;2)How to achieve targeted therapy of some drugs in the gastrointestinal tract? Based on these two issues, drugdelivery microrobots have shown great application prospect in oral drug delivery due to their characteristics offlexible locomotion or driven ability. Therefore, this paper summarizes various drug delivery microrobotsdeveloped in recent years and divides them into four categories according to different driving modes: magneticcontrolleddrug delivery microrobots, anchored drug delivery microrobots, self-propelled drug delivery microrobotsand biohybrid drug delivery microrobots. As oral drug delivery microrobots involve disciplines such asmaterials science, mechanical engineering, medicine, and control systems, this paper begins by introducing thegastrointestinal barriers that oral drug delivery must overcome. Subsequently, it provides an overview of typicalmaterials involved in the design process of oral drug delivery microrobots. To enhance readers’ understanding ofthe working principles and design process of oral drug delivery microrobots, we present a guideline for designingsuch microrobots. Furthermore, the current development status of various types of oral drug delivery microrobotsis reviewed, summarizing their respective advantages and limitations. Finally, considering the significantconcerns regarding safety and clinical translation, we discuss the challenges and prospections of clinical translationfor various oral drug delivery microrobots presented in this paper, providing corresponding suggestions foraddressing some existing challenges.
