マルチ スケール キノウ ヲ ユウスル コウソク ジドウ マイクロ マニピュレーション システム

Ebubekir Avci, Chanh-Nghiem Nguyen, Kenichi Ohara, Yasushi Mae, Tatsuo Arai, Analysis and suppression of residual vibration in microhand for high-speed single-cell manipulation, International Journal of Mechatronics and Automation, 2013-Vol.3, No.2, pp.110-11

Elastic Inflatable Actuators for Soft Robotic Applications

The 20th century’s robotic systems have been made out of stiff materials and much of the developments in the field have pursued ever more accurate and dynamic robots which thrive in industrial automation settings and will probably continue to do so for many decades to come. However, the 21st century’s robotic legacy may very well become that of soft robots. This emerging domain is characterized by continuous soft structures that simultaneously fulfil the role of robotic link and robotic actuator, where prime focus is on design and fabrication of the robotic hardware instead of software control to achieve a desired operation. These robots are anticipated to take a prominent role in delicate tasks where classic robots fail, such as in minimally invasive surgery, active prosthetics and automation tasks involving delicate irregular objects. Central to the development of these robots is the fabrication of soft actuators to generate movement. This paper reviews a particularly attractive type of soft actuators that are driven by pressurized fluids. These actuators have recently gained substantial traction on the one hand due to the technology push from better simulation tools and new manufacturing technologies including soft-lithography and additive manufacturing, and on the other hand by a market pull from the applications listed above. This paper provides an overview of the different advanced soft actuator configurations, their design, fabrication and applications.This research is supported by the Fund for Scientific Research-Flanders (FWO), and the European Research Council (ERC starting grant HIENA)

Elastic Inflatable Actuators for Soft Robotic Applications

The 20th century’s robotic systems have been made out of stiff materials and much of the developments in the field have pursued ever more accurate and dynamic robots which thrive in industrial automation settings and will probably continue to do so for many decades to come. However, the 21st century’s robotic legacy may very well become that of soft robots. This emerging domain is characterized by continuous soft structures that simultaneously fulfil the role of robotic link and robotic actuator, where prime focus is on design and fabrication of the robotic hardware instead of software control to achieve a desired operation. These robots are anticipated to take a prominent role in delicate tasks where classic robots fail, such as in minimally invasive surgery, active prosthetics and automation tasks involving delicate irregular objects. Central to the development of these robots is the fabrication of soft actuators to generate movement. This paper reviews a particularly attractive type of soft actuators that are driven by pressurized fluids. These actuators have recently gained substantial traction on the one hand due to the technology push from better simulation tools and new manufacturing technologies including soft-lithography and additive manufacturing, and on the other hand by a market pull from the applications listed above. This paper provides an overview of the different advanced soft actuator configurations, their design, fabrication and applications.This research is supported by the Fund for Scientific Research-Flanders (FWO), and the European Research Council (ERC starting grant HIENA)

Scalability study for robotic hand platform

The goal of this thesis project was to determine the lower limit of scale for the RIT robotic grasping hand. This was accomplished using a combination of computer simulation and experimental studies. A force analysis was conducted to determine the size of air muscles required to achieve appropriate contact forces at a smaller scale. Input variables, such as the actuation force and tendon return force, were determined experimentally. A dynamic computer model of the hand system was then created using Recurdyn. This was used to predict the contact (grasping) force of the fingers at full-scale, half-scale, and quarter-scale. Correlation between the computer model and physical testing was achieved for both a life-size and half-scale finger assembly. To further demonstrate the scalability of the hand design, both half and quarter-scale robotic hand rapid prototype assemblies were built using 3D printing techniques. This thesis work identified the point where further miniaturization would require a change in the manufacturing process to micro-fabrication. Several techniques were compared as potential methods for making a production intent quarter-scale robotic hand. Investment casting, Swiss machining, and Selective Laser Sintering were the manufacturing techniques considered. A quarter-scale robotic hand tested the limits of each technology. Below this scale, micro-machining would be required. The break point for the current actuation method, air muscles, was also explored. Below the quarter-scale, an alternative actuation method would also be required. Electroactive Polymers were discussed as an option for the micro-scale. In summary, a dynamic model of the RIT robotic grasping hand was created and validated as scalable at full and half-scales. The model was then used to predict finger contact forces at the quarter-scale. The quarter-scale was identified as the break point in terms of the current RIT robotic grasping hand based on both manufacturing and actuation. A novel, prototype quarter-scale robotic hand assembly was successfully built by an additive manufacturing process, a high resolution 3D printer. However, further miniaturization would require alternate manufacturing techniques and actuation mechanisms

Development of novel micropneumatic grippers for biomanipulation

Microbjects with dimensions from 1 μm to 1 mm have been developed recently for different aspects and purposes. Consequently, the development of handling and manipulation tools to fulfil this need is urgently required. Micromanipulation techniques could be generally categorized according to their actuation method such as electrostatic, thermal, shape memory alloy, piezoelectric, magnetic, and fluidic actuation. Each of which has its advantage and disadvantage. The fluidic actuation has been overlooked in MEMS despite its satisfactory output in the micro-scale. This thesis presents different families of pneumatically driven, low cost, compatible with biological environment, scalable, and controllable microgrippers. The first family demonstrated a polymeric microgripper that was laser cut and actuated pneumatically. It was tested to manipulate microparticles down to 200 microns. To overcome the assembly challenges that arise in this family, the second family was proposed. The second family was a micro-cantilever based microgripper, where the device was assembled layer by layer to form a 3D structure. The microcantilevers were fabricated using photo-etching technique, and demonstrated the applicability to manipulate micro-particles down to 200 microns using automated pick-and-place procedure. In addition, this family was used as a tactile-detector as well. Due to the angular gripping scheme followed by the above mentioned families, gripping smaller objects becomes a challenging task. A third family following a parallel gripping scheme was proposed allowing the gripping of smaller objects to be visible. It comprises a compliant structure microgripper actuated pneumatically and fabricated using picosecond laser technology, and demonstrated the capability of gripping microobject as small as 100 μm microbeads. An FEA modelling was employed to validate the experimental and analytical results, and excellent matching was achieved

Viscoelasticity and Structure of Soft Biological Interfaces: From Artificial Models to Living Tissues

The primary aim of this thesis is to shed a quantitative light on the mechanics of dynamic biological interfaces with different levels of structural complexities, ranging from lung surfactant models to regenerating tissues. In chapter 3, the correlation between biophysical properties and function of the native extracellular matrix (ECM), mesoglea, of the freshwater polyp Hydra was studied. In the body design of Hydra, mesoglea acts as an interlayer between external (ectodermal) and internal (endodermal) cell layers, sustaining the mechanical integrity of polyps. In this study, nano-focused grazing incidence small angle X-ray scattering on isolated mesoglea revealed that the packing order of Hydra collagen type I was comparable to its vertebrate homologue. The structure was anisotropic with respect to the oral-aboral axis, supporting the extensive extension and contractions of the body along this axis. In the next step, the spatio-temporal evolution of mesoglea mechanics was tracked ex vivo by nano-indentation using an atomic force microscope. The experimental data demonstrated that freshly detached polyps initially had a uniformly soft mesoglea, but mesoglea changed the characteristic "elasticity patterns" during the asexual reproduction. This change could be explained by a quantitative proteome analysis, implying that the mechanical remodeling of Hydra was highly correlated with protease expression activity. When the body column tissue was transformed into head tissue either by a drug or by the over-expression of β-catenin, mesoglea had low elastic moduli over the whole body. This result suggests that the spatio-temporal patterns in mesoglea mechanics is strongly correlated with the stem cell activity. In chapter 4 a highly sensitive two-fingered micro-robotic hand was used to determine the viscoelastic properties of Hydra tissue fragments (regenerates) during early stages of regeneration. Owing to the dexterous grasping motion of microobjects realized by the micro-robot, the bulk elastic modulus of Hydra regenerates could be determined by linearly compressing the tissue by keeping the strain level low. Under a constant strain, the stress relaxation behavior could be interpreted by applying the Maxwell model of viscoelastic materials, yielding the Stokes frictional coefficient and viscous modulus. Furthermore, the forces actively generated by the regenerate were measured and shown to correlate well with shape fluctuations of a freely regenerating sample. In chapter 5, lung surfactant inactivation by serum proteins during the acute respiratory distress syndrome (ARDS) was simulated. As the model of dynamic, oscillating interfaces in lung, the competitive adsorption of dipalmitoylphosphatidylcholine (DPPC) and bovine serum albumin (BSA) to the air/water interface was monitored by periodically changing the surface area. The model was used to investigate the impact of perfluorohexane (PFH) as a potential therapeutics. The lipid-protein composite films at the air/water interface in the presence and absence of PFH gas could be visualized by fluorescence microscopy, indicating an accelerated displacement of a pre-adsorbed BSA by DPPC in saturated PFH atmosphere. The acceleration of BSA-DPPC replacement under PFH atmosphere was accompanied by significant changes in viscoelasticity of the interface, suggesting the incorporation of PFH to the protein layer

Stimuli-Responsive Microtools for Biomedical and Defense Applications

We live in a 3D world which has embraced ever shrinking technologies, yet the techniques used to create these micro- and nanoscale technologies are inherently 2D. Self-assembly of 2D templates into 3D devices enables the creation of complex tools cheaply, efficiently, and in mass quantity. I utilize this technique to create stimuli-responsive microgrippers, which are shaped like hands with flexible joints and rigid phalanges and range in size from 10 µm to 4 mm. Intrinsic stress within the hinges provides all the energy necessary for gripping, and thus they require no wires or batteries for operation. Here, I demonstrate their use for both biomedical and defense applications. These microgrippers can be used as microsurgical tools, gripping onto tissue in response to body temperature and excising tissue from the gastrointestinal tract in both in vivo and ex vivo porcine models. A Monte Carlo model confirmed that these tiny tools has a higher probability of sampling tissue from a lesion as compared to the traditional biopsy foreceps. These grippers were scaled down to 10 µm and used to capture single cells for in vitro isolation, imaging, and assays. All-polymeric, porous, stimuli-responsive therapeutic grippers or “theragrippers” which swell and de-swell around body temperature were created for drug delivery applications. These theragrippers can be loaded with commercial drugs for biphasic, site-specific controlled release and were successfully demonstrated in an in vitro and an in vivo model. For defense applications, integrating microelectronics like RFID’s onto the microgrippers creates tagging, tracking, and locating (TTL) devices capable of latching onto clothing, hair, and moving animal targets. This integrated design is enabled using high throughput solder-based self-assembly. This defense application, particularly reliant on covert, wireless technology, benefits from our novel photothermal actuation mechanism using low power, handheld lasers. In addition to triggering microgripper closing, this actuation scheme also enables complex sequential folding pathways, a step towards programmable matter

Control techniques for mechatronic assisted surgery

The treatment response for traumatic head injured patients can be improved by using an autonomous robotic system to perform basic, time-critical emergency neurosurgery, reducing costs and saving lives. In this thesis, a concept for a neurosurgical robotic system is proposed to perform three specific emergency neurosurgical procedures; they are the placement of an intracranial pressure monitor, external ventricular drainage, and the evacuation of chronic subdural haematoma. The control methods for this system are investigated following a curiosity led approach. Individual problems are interpreted in the widest sense and solutions posed that are general in nature. Three main contributions result from this approach: 1) a clinical evidence based review of surgical robotics and a methodology to assist in their evaluation, 2) a new controller for soft-grasping of objects, and 3) new propositions and theorems for chatter suppression sliding mode controllers. These contributions directly assist in the design of the control system of the neurosurgical robot and, more broadly, impact other areas outside the narrow con nes of the target application. A methodology for applied research in surgical robotics is proposed. The methodology sets out a hierarchy of criteria consisting of three tiers, with the most important being the bottom tier and the least being the top tier. It is argued that a robotic system must adhere to these criteria in order to achieve acceptability. Recent commercial systems are reviewed against these criteria, and are found to conform up to at least the bottom and intermediate tiers. However, the lack of conformity to the criteria in the top tier, combined with the inability to conclusively prove increased clinical benefit, particularly symptomatic benefit, is shown to be hampering the potential of surgical robotics in gaining wide establishment. A control scheme for soft-grasping objects is presented. Grasping a soft or fragile object requires the use of minimum contact force to prevent damage or deformation. Without precise knowledge of object parameters, real-time feedback control must be used to regulate the contact force and prevent slip. Moreover, the controller must be designed to have good performance characteristics to rapidly modulate the fingertip contact force in response to a slip event. A fuzzy sliding mode controller combined with a disturbance observer is proposed for contact force control and slip prevention. The robustness of the controller is evaluated through both simulation and experiment. The control scheme was found to be effective and robust to parameter uncertainty. When tested on a real system, however, chattering phenomena, well known to sliding mode research, was induced by the unmodelled suboptimal components of the system (filtering, backlash, and time delays). This reduced the controller performance. The problem of chattering and potential solutions are explored. Real systems using sliding mode controllers, such as the control scheme for soft-grasping, have a tendency to chatter at high frequencies. This is caused by the sliding mode controller interacting with un-modelled parasitic dynamics at the actuator-input and sensor-output of the plant. As a result, new chatter-suppression sliding mode controllers have been developed, which introduce new parameters into the system. However, the effect any particular choice of parameters has on system performance is unclear, and this can make tuning the parameters to meet a set of performance criteria di cult. In this thesis, common chatter-suppression sliding mode control strategies are surveyed and simple design and estimation methods are proposed. The estimation methods predict convergence, chattering amplitude, settling time, and maximum output bounds (overshoot) using harmonic linearizations and invariant ellipsoid sets

The development of optical nanomachines for studying molecules : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Mechatronics Engineering at Massey University, Palmerston North, New Zealand

Chapter 3 is ©2020 IEEE. Accepted manuscript is reprinted, with permission, from 2020 IEEE/ASME International Conference on Advanced Intelligent Mechatronics (AIM). Chapter 5 is ©2022 IEEE. Accepted manuscript is reprinted, with permission, from 2022 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS).Optical tweezers have been used for a number of applications since their invention by Arthur Ashkin in 1986, and are particularly useful for biological and biophysical studies due to their exceptionally high spatial and force-based resolution. The same intense laser focus that allows light to be used as a tool for micro-nanoscale manipulation also has the potential to damage the objects being studied, and the extremely high force resolution is coupled with the limitation of very low forces. There is potential to overcome these drawbacks of optical manipulation through making use of another laser based technique: two-photon absorption polymerisation (TPAP). This thesis has brought these together to demonstrate the uses of optical nanomachines as helpful tools for optical tweezer studies. The project was highly interdisciplinary, concerning the intersection of optical trapping, 3D micromachine design and development, and DNA stretching. The thesis was based around the strategy of first developing microrobots and demonstrating their manipulation using optical tweezers, then adjusting the design for specific applications. Microlevers were developed for lever-assisted DNA stretching and amplification of optical forces. The influence of design features and TPAP parameters on microlever functionality was investigated; particularly the influence of overlapping area and presence of supports, and the effects of differently shaped "trapping handles". These features were important as lever functionality was tested in solutions of different ionic strength, and stable trapping of the levers was required for force amplification. DNA stretching was chosen as a target application for distanced-application of optical forces due to its status as a well-known and characterised example of single-molecule studies with optical tweezers. Amplification of optical forces was also seen as an application that could demonstrate the utility of optical micromachines, and microlevers with a 2:1 lever arm ratio were developed to produce consistent, two-fold amplification of optical forces, in a first for unsupported, pin-jointed optical microrobotics. It is hoped that in the future fully-remote, micromachine-assisted studies will extend optical tweezer studies of laser-sensitive subjects, as well as increasing the forces that can be applied, and the results obtained in this thesis are encouraging. All in all, the thesis confirms the potential of optical micromachines for aiding studies using optical tweezers, and demonstrates concrete progress in both design and application