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
Locomotion performance degradation after carrying payloads is a significant challenge for insect-scale microrobots.Previously,a legged microrobot named BHMbot with a high load-carrying capacity based on front-leg actu...Locomotion performance degradation after carrying payloads is a significant challenge for insect-scale microrobots.Previously,a legged microrobot named BHMbot with a high load-carrying capacity based on front-leg actuation configuration and efficient running gait was proposed.However,insects,mammals and reptiles in nature typically use their powerful rear legs to achieve rapid running gaits for predation or risk evasion.In this work,the load-carrying capacity of the BHMbots with front-leg actuation and rear-leg actuation configurations is comparatively studied.Simulations based on a dynamic model with four degrees of freedom,along with experiments,have been conducted to analyze the locomotion characteristics of the two configurations under different payload masses.Both simulation and experimental results indicate that the load-carrying capacity of the microrobots is closely related to their actuation configurations,which leads to different dynamic responses of the microrobots after carrying varying payload masses.For microrobots with body lengths of 15 mm,the rear-leg actuation configuration exhibits a 31.2%enhancement in running speed compared to the front-leg actuation configuration when unloaded.Conversely,when carrying payloads exceeding 5.7 times the body mass(350 mg),the rear-leg actuation configuration demonstrates an 80.1%reduction in running speed relative to the front-leg actuation configuration under the same payload conditions.展开更多
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
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
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
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
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
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
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
Until now,although nanomedicines have gained much success in tumor treatment by reducing severe toxic side effects of drugs and improving the therapeutic efficiency of drugs,they are still faced with thorny challenges...Until now,although nanomedicines have gained much success in tumor treatment by reducing severe toxic side effects of drugs and improving the therapeutic efficiency of drugs,they are still faced with thorny challenges in targeted drug delivery including insufficient targeting accuracy,poor penetration into tumor core,and systemic toxicity issues.Recently,engineering nano/microrobots with multiple remarkable properties such as real-time sensing,interacting and manipulating capabilities,and programmability,have received increasing attention in biomedical applications ranging from disease diagnosis,targeted drug delivery,medical imaging,and surgery.More importantly,in different driven modes,nano/microrobots are capable of performing a wide variety of powerful functions,such as enhancing tissue penetration and payload retention in deep-seated tumors with active navigation,being programmable to release drugs or performing specific tasks directly at the tumor site with high precision and accuracy,automating repeated tumor treatment without the need for frequent interventions,and minimizing out-of-target tissue damage,leading to a huge exploration potential in tumor treatment.In this review,we delve into the recent progress and the development direction of nano/microrobots for tumor treatment and emphasize the working mechanisms and the unique functionalities of different driven modes in detail.Meanwhile,we elaborate on the application of nano/microrobots fabricated from various types of materials in tumor therapy.Finally,the key factors to be considered in the clinical translation of the above nano/microrobots are proposed.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
Microrobots-assisted drug delivery and surgery have been always in the spotlight and are highly anticipated to solve the challenges of cancer in situ treatment. These versatile small biomedical robots are expected to ...Microrobots-assisted drug delivery and surgery have been always in the spotlight and are highly anticipated to solve the challenges of cancer in situ treatment. These versatile small biomedical robots are expected to realize direct access to the tumor or disease site for precise treatment, which requires real-time and high-resolution in vivo tracking as feedback for the microrobots’ actuation and control. Among current biomedical imaging methods, photoacoustic imaging(PAI) is presenting its outstanding performances in the tracking of microrobots in the human body derived from its great advantages of excellent imaging resolution and contrast in deep tissue. In this review, we summarize the PAI techniques, imaging systems, and their biomedical applications in microrobots tracking in vitro and in vivo. From a robotic tracking perspective,we also provide some insight into the future of PAI technology in clinical applications.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
Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined sp...Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes.展开更多
Magnetically driven microrobots hold great potential to perform specific tasks more locally and less invasively in the human body.To reach the lesion area in vivo,microrobots should usually be navigated in flowing blo...Magnetically driven microrobots hold great potential to perform specific tasks more locally and less invasively in the human body.To reach the lesion area in vivo,microrobots should usually be navigated in flowing blood,which is much more complex than static liquid.Therefore,it is more challenging to design a corresponding precise control scheme.A considerable amount of work has been done regarding control of magnetic microrobots in a flow and the corresponding theories.In this paper,we review and summarize the state-of-the-art research progress concerning magnetic microrobots in blood flow,including the establishment of flow systems,dynamics modeling of motion,and control methods.In addition,current challenges and limitations are discussed.We hope this work can shed light on the efficient control of microrobots in complex flow environments and accelerate the study of microrobots for clinical use.展开更多
Insect-scale flapping wing aerial robots actuated by piezoelectric materials—known for their high power density and rapid frequency response—have recently garnered increasing attention.However,the limited output dis...Insect-scale flapping wing aerial robots actuated by piezoelectric materials—known for their high power density and rapid frequency response—have recently garnered increasing attention.However,the limited output displacement of piezoelectric actuators results in complex transmission methods that are challenging to assemble.Furthermore,high piezoelectric coefficient materials capable of large displacements for direct wing actuation are fragile,costly,and relatively bulky.This article presents a novel design for minimalist insect-scale aerial robots,where piezoelectric bimorph PZT actuators directly drive two pairs of wings,thus eliminating complex transmission mechanisms and reducing fabrication complexity.These robots demonstrate high liftoff speeds and favorable lift-to-weight ratios,and they can achieve vertical ascent under uncontrolled open-loop conditions.The piezoelectric direct-driven twowing insect-scale aerial robot,based on this approach,features an 8 cm wingspan and a prototype weight of 140 mg,successfully achieving takeoff under unconstrained conditions with an external power source.To further enhance insect-scale aerial robot performance,we optimized the wing-to-actuator ratio and wing arrangement.We propose a biaxial aerial robot with an X-shaped structure,a 2:1 wing-toactuator ratio,a 70 mm wingspan,and a total mass of 160 mg.This structure demonstrates a high lift-to-weight ratio of 2.8:1.During free flight,when powered externally,it attains a maximum takeoff speed exceeding 1 m/s and achieves a vertical takeoff height surpassing 80 cm under uncontrolled conditions.Consequently,it ranks among the fastest prototypes in the milligram-scale weight category.展开更多
Treatment of intracranial gliomas has increasingly favored minimally invasive surgery,with a growing focus on leveraging microrobots for efficient drug delivery while overcoming the impact of body fluids.Inspired by h...Treatment of intracranial gliomas has increasingly favored minimally invasive surgery,with a growing focus on leveraging microrobots for efficient drug delivery while overcoming the impact of body fluids.Inspired by honeybee stingers,this study proposed a novel microspike robot.This robot firmly adhered to the tissue surface,enabling direct drug delivery from a hydrogel on its back into the targeted tissue via microspikes.The drug delivery rate was influenced by temperature and could be controlled by an alternating magnetic field.Microrobots could be delivered rapidly through a clinical Ommaya reservoir into the postoperative cavity or ventricle of the skull.The microrobot could be actuated for adhesion and retrieval,with its motion posture and trajectory highly precisely controlled by external magnetic fields.Biological experiments confirmed the excellent biocompatibility and biosafety of the microspike robot and demonstrated its effectiveness in treating gliomas by loading unconventional therapeutic drugs.The proposed microspike robot has significant potential for long-term drug delivery to target gliomas and other future clinical applications.展开更多
Microassembly platforms have attracted significant attention recently because of their potential for developing microsystems and devices for a wide range of applications.Despite their considerable poten-tial,existing ...Microassembly platforms have attracted significant attention recently because of their potential for developing microsystems and devices for a wide range of applications.Despite their considerable poten-tial,existing techniques are mainly used in laboratory research settings.This review provides an over-view of the fundamentals,techniques,and applications of microassemblies.Manipulation techniques based on magnetic,optical,acoustic fields,and mechanical systems are discussed,and control systems that rely on machine vision and force feedback are introduced.Additionally,recent applications of microassemblies in microstructure fabrication,microelectromechanical operation,and biomedical engi-neering are examined.This review also highlights unmet technical demands and emerging trends,as well as new research opportunities in this expanding field of research driven by allied technologies such as microrobotics.展开更多
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 in part by Beijing Natural Science Foundation under Grant 3232010in part by the National Natural Science Foundation of China under Grant 12002017+2 种基金in part by AECC Industry-university Collocation Fund under Grant HFZL2023CXY026in part by Beihang Outstanding Young Scholars Project under Grant YWF-23-L-1201in part by 111 Project under Grant B08009.
文摘Locomotion performance degradation after carrying payloads is a significant challenge for insect-scale microrobots.Previously,a legged microrobot named BHMbot with a high load-carrying capacity based on front-leg actuation configuration and efficient running gait was proposed.However,insects,mammals and reptiles in nature typically use their powerful rear legs to achieve rapid running gaits for predation or risk evasion.In this work,the load-carrying capacity of the BHMbots with front-leg actuation and rear-leg actuation configurations is comparatively studied.Simulations based on a dynamic model with four degrees of freedom,along with experiments,have been conducted to analyze the locomotion characteristics of the two configurations under different payload masses.Both simulation and experimental results indicate that the load-carrying capacity of the microrobots is closely related to their actuation configurations,which leads to different dynamic responses of the microrobots after carrying varying payload masses.For microrobots with body lengths of 15 mm,the rear-leg actuation configuration exhibits a 31.2%enhancement in running speed compared to the front-leg actuation configuration when unloaded.Conversely,when carrying payloads exceeding 5.7 times the body mass(350 mg),the rear-leg actuation configuration demonstrates an 80.1%reduction in running speed relative to the front-leg actuation configuration under the same payload conditions.
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.
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 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 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 Science Foundation of China(8217070298,81773283).
文摘Until now,although nanomedicines have gained much success in tumor treatment by reducing severe toxic side effects of drugs and improving the therapeutic efficiency of drugs,they are still faced with thorny challenges in targeted drug delivery including insufficient targeting accuracy,poor penetration into tumor core,and systemic toxicity issues.Recently,engineering nano/microrobots with multiple remarkable properties such as real-time sensing,interacting and manipulating capabilities,and programmability,have received increasing attention in biomedical applications ranging from disease diagnosis,targeted drug delivery,medical imaging,and surgery.More importantly,in different driven modes,nano/microrobots are capable of performing a wide variety of powerful functions,such as enhancing tissue penetration and payload retention in deep-seated tumors with active navigation,being programmable to release drugs or performing specific tasks directly at the tumor site with high precision and accuracy,automating repeated tumor treatment without the need for frequent interventions,and minimizing out-of-target tissue damage,leading to a huge exploration potential in tumor treatment.In this review,we delve into the recent progress and the development direction of nano/microrobots for tumor treatment and emphasize the working mechanisms and the unique functionalities of different driven modes in detail.Meanwhile,we elaborate on the application of nano/microrobots fabricated from various types of materials in tumor therapy.Finally,the key factors to be considered in the clinical translation of the above nano/microrobots are proposed.
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This work was partially supported by the Research Grants Council of the Hong Kong Special Administrative Region(Nos.11103320,11215817,and 11101618)。
文摘Microrobots-assisted drug delivery and surgery have been always in the spotlight and are highly anticipated to solve the challenges of cancer in situ treatment. These versatile small biomedical robots are expected to realize direct access to the tumor or disease site for precise treatment, which requires real-time and high-resolution in vivo tracking as feedback for the microrobots’ actuation and control. Among current biomedical imaging methods, photoacoustic imaging(PAI) is presenting its outstanding performances in the tracking of microrobots in the human body derived from its great advantages of excellent imaging resolution and contrast in deep tissue. In this review, we summarize the PAI techniques, imaging systems, and their biomedical applications in microrobots tracking in vitro and in vivo. From a robotic tracking perspective,we also provide some insight into the future of PAI technology in clinical applications.
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.
基金supported by the National Key Research and Development Program of China(No.2024YFB3212901)National Natural Science Foundation of China(12072189)the Medicine and Engineering Interdisciplinary Research Fund of Shanghai Jiao Tong University(No.YG2025ZD05)。
文摘Pipelines are extensively used in environments such as nuclear power plants,chemical factories,and medical devices to transport gases and liquids.These tubular environments often feature complex geometries,confined spaces,and millimeter-scale height restrictions,presenting significant challenges to conventional inspection methods.Here,we present an ultrasonic microrobot(weight,80 mg;dimensions,24 mm×7 mm;thickness,210μm)to realize agile and bidirectional navigation in narrow pipelines.The ultrathin structural design of the robot is achieved through a high-performance piezoelectric composite film microstructure based on MEMS technology.The robot exhibits various vibration modes when driven by ultrasonic frequency signals,its motion speed reaches81 cm s-1 at 54.8 k Hz,exceeding that of the fastest piezoelectric microrobots,and its forward and backward motion direction is controllable through frequency modulation,while the minimum driving voltage for initial movement can be as low as 3 VP-P.Additionally,the robot can effortlessly climb slopes up to 24.25°and carry loads more than 36 times its weight.The robot is capable of agile navigation through curved L-shaped pipes,pipes made of various materials(acrylic,stainless steel,and polyvinyl chloride),and even over water.To further demonstrate its inspection capabilities,a micro-endoscope camera is integrated into the robot,enabling real-time image capture inside glass pipes.
基金supported by the Shenzhen Institute of Artificial Intelligence and Robotics for Society,China (No.AC01202101106)。
文摘Magnetically driven microrobots hold great potential to perform specific tasks more locally and less invasively in the human body.To reach the lesion area in vivo,microrobots should usually be navigated in flowing blood,which is much more complex than static liquid.Therefore,it is more challenging to design a corresponding precise control scheme.A considerable amount of work has been done regarding control of magnetic microrobots in a flow and the corresponding theories.In this paper,we review and summarize the state-of-the-art research progress concerning magnetic microrobots in blood flow,including the establishment of flow systems,dynamics modeling of motion,and control methods.In addition,current challenges and limitations are discussed.We hope this work can shed light on the efficient control of microrobots in complex flow environments and accelerate the study of microrobots for clinical use.
基金supported by the National Natural Science Foundation of China(No.52475039)。
文摘Insect-scale flapping wing aerial robots actuated by piezoelectric materials—known for their high power density and rapid frequency response—have recently garnered increasing attention.However,the limited output displacement of piezoelectric actuators results in complex transmission methods that are challenging to assemble.Furthermore,high piezoelectric coefficient materials capable of large displacements for direct wing actuation are fragile,costly,and relatively bulky.This article presents a novel design for minimalist insect-scale aerial robots,where piezoelectric bimorph PZT actuators directly drive two pairs of wings,thus eliminating complex transmission mechanisms and reducing fabrication complexity.These robots demonstrate high liftoff speeds and favorable lift-to-weight ratios,and they can achieve vertical ascent under uncontrolled open-loop conditions.The piezoelectric direct-driven twowing insect-scale aerial robot,based on this approach,features an 8 cm wingspan and a prototype weight of 140 mg,successfully achieving takeoff under unconstrained conditions with an external power source.To further enhance insect-scale aerial robot performance,we optimized the wing-to-actuator ratio and wing arrangement.We propose a biaxial aerial robot with an X-shaped structure,a 2:1 wing-toactuator ratio,a 70 mm wingspan,and a total mass of 160 mg.This structure demonstrates a high lift-to-weight ratio of 2.8:1.During free flight,when powered externally,it attains a maximum takeoff speed exceeding 1 m/s and achieves a vertical takeoff height surpassing 80 cm under uncontrolled conditions.Consequently,it ranks among the fastest prototypes in the milligram-scale weight category.
基金supported by the National Key R&D Program of China(No.2023YFB4705600)the National Natural Science Foundation of China(Nos.U23A20342,62273331,61925307,and 61821005)+1 种基金the CAS Project for Young Scientists in Basic Research(No.YSBR-036)the CAS/SAFEA International Partnership Program for Creative Research Teams.
文摘Treatment of intracranial gliomas has increasingly favored minimally invasive surgery,with a growing focus on leveraging microrobots for efficient drug delivery while overcoming the impact of body fluids.Inspired by honeybee stingers,this study proposed a novel microspike robot.This robot firmly adhered to the tissue surface,enabling direct drug delivery from a hydrogel on its back into the targeted tissue via microspikes.The drug delivery rate was influenced by temperature and could be controlled by an alternating magnetic field.Microrobots could be delivered rapidly through a clinical Ommaya reservoir into the postoperative cavity or ventricle of the skull.The microrobot could be actuated for adhesion and retrieval,with its motion posture and trajectory highly precisely controlled by external magnetic fields.Biological experiments confirmed the excellent biocompatibility and biosafety of the microspike robot and demonstrated its effectiveness in treating gliomas by loading unconventional therapeutic drugs.The proposed microspike robot has significant potential for long-term drug delivery to target gliomas and other future clinical applications.
基金supported by Shanghai Municipal Science and Technology Major Project(2021SHZDZX)also in part supported by the Science and Technology Commission of Shanghai Municipality(20DZ2220400).
文摘Microassembly platforms have attracted significant attention recently because of their potential for developing microsystems and devices for a wide range of applications.Despite their considerable poten-tial,existing techniques are mainly used in laboratory research settings.This review provides an over-view of the fundamentals,techniques,and applications of microassemblies.Manipulation techniques based on magnetic,optical,acoustic fields,and mechanical systems are discussed,and control systems that rely on machine vision and force feedback are introduced.Additionally,recent applications of microassemblies in microstructure fabrication,microelectromechanical operation,and biomedical engi-neering are examined.This review also highlights unmet technical demands and emerging trends,as well as new research opportunities in this expanding field of research driven by allied technologies such as microrobotics.
