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

Augmentation Of Human Skill In Microsurgery

Surgeons performing highly skilled microsurgery tasks can benefit from information and manual assistance to overcome technological and physiological limitations to make surgery safer, efficient, and more successful. Vitreoretinal surgery is particularly difficult due to inherent micro-scale and fragility of human eye anatomy. Additionally, surgeons are challenged by physiological hand tremor, poor visualization, lack of force sensing, and significant cognitive load while executing high-risk procedures inside the eye, such as epiretinal membrane peeling. This dissertation presents the architecture and the design principles for a surgical augmentation environment which is used to develop innovative functionality to address the fundamental limitations in vitreoretinal surgery. It is an inherently information driven modular system incorporating robotics, sensors, and multimedia components. The integrated nature of the system is leveraged to create intuitive and relevant human-machine interfaces and generate a particular system behavior to provide active physical assistance and present relevant sensory information to the surgeon. These include basic manipulation assistance, audio-visual and haptic feedback, intraoperative imaging and force sensing. The resulting functionality, and the proposed architecture and design methods generalize to other microsurgical procedures. The system's performance is demonstrated and evaluated using phantoms and in vivo experiments

Modular MRI Guided Device Development System: Development, Validation and Applications

Since the first robotic surgical intervention was performed in 1985 using a PUMA industrial manipulator, development in the field of surgical robotics has been relatively fast paced, despite the tremendous costs involved in developing new robotic interventional devices. This is due to the clear advantages to augmented a clinicians skill and dexterity with the precision and reliability of computer controlled motion. A natural extension of robotic surgical intervention is the integration of image guided interventions, which give the promise of reduced trauma, procedure time and inaccuracies. Despite magnetic resonance imaging (MRI) being one of the most effective imaging modalities for visualizing soft tissue structures within the body, MRI guided surgical robotics has been frustrated by the high magnetic field in the MRI image space and the extreme sensitivity to electromagnetic interference. The primary contributions of this dissertation relate to enabling the use of direct, live MR imaging to guide and assist interventional procedures. These are the two focus areas: creation both of an integrated MRI-guided development platform and of a stereotactic neural intervention system. The integrated series of modules of the development platform represent a significant advancement in the practice of creating MRI guided mechatronic devices, as well as an understanding of design requirements for creating actuated devices to operate within a diagnostic MRI. This knowledge was gained through a systematic approach to understanding, isolating, characterizing, and circumventing difficulties associated with developing MRI-guided interventional systems. These contributions have been validated on the levels of the individual modules, the total development system, and several deployed interventional devices. An overview of this work is presented with a summary of contributions and lessons learned along the way

Medical Robotics

The first generation of surgical robots are already being installed in a number of operating rooms around the world. Robotics is being introduced to medicine because it allows for unprecedented control and precision of surgical instruments in minimally invasive procedures. So far, robots have been used to position an endoscope, perform gallbladder surgery and correct gastroesophogeal reflux and heartburn. The ultimate goal of the robotic surgery field is to design a robot that can be used to perform closed-chest, beating-heart surgery. The use of robotics in surgery will expand over the next decades without any doubt. Minimally Invasive Surgery (MIS) is a revolutionary approach in surgery. In MIS, the operation is performed with instruments and viewing equipment inserted into the body through small incisions created by the surgeon, in contrast to open surgery with large incisions. This minimizes surgical trauma and damage to healthy tissue, resulting in shorter patient recovery time. The aim of this book is to provide an overview of the state-of-art, to present new ideas, original results and practical experiences in this expanding area. Nevertheless, many chapters in the book concern advanced research on this growing area. The book provides critical analysis of clinical trials, assessment of the benefits and risks of the application of these technologies. This book is certainly a small sample of the research activity on Medical Robotics going on around the globe as you read it, but it surely covers a good deal of what has been done in the field recently, and as such it works as a valuable source for researchers interested in the involved subjects, whether they are currently “medical roboticists” or not

Doctor of Philosophy

dissertationIn this dissertation, we present methods for intuitive telemanipulation of manipulators that use piezoelectric stick-slip actuators (PSSAs). Commercial micro/nano-manipulators, which utilize PSSAs to achieve high precision over a large workspace, are typically controlled by a human operator at the joint level, leading to unintuitive and time-consuming telemanipulation. Prior work has considered the use of computer-vision-feedback to close a control loop for improved performance, but computer-vision-feedback is not a viable option for many end users. We discuss how open-loop models of the micro/nano-manipulator can be used to achieve desired end-effector movements, and we explain the process of obtaining open-loop models. We propose a rate-control telemanipulation method that utilizes the obtained model, and we experimentally quantify the effectiveness of the method using a common commercial manipulator (the Kleindiek MM3A). The utility of open-loop control methods for PSSAs with a human in the loop depends directly on the accuracy of the open-loop models of the manipulator. Prior research has shown that modeling of piezoelectric actuators is not a trivial task as they are known to suffer from nonlinearities that degrade their performance. We study the effect of static (non-inertial) loads on a prismatic and a rotary PSSA, and obtain a model relating the step size of the actuator to the load. The actuator-specific parameters of the model are calibrated by taking measurements in specific configurations of the manipulator. Results comparing the obtained model to experimental data are presented. PSSAs have properties that make them desirable over traditional DC-motor actuators for use in retinal surgery. We present a telemanipulation system for retinal surgery that uses a full range of existing disposable instruments. The system uses a PSSA-based manipulator that is compact and light enough that it could reasonably be made head-mounted to passively compensate for head movements. Two mechanisms are presented that enable the system to use existing disposable actuated instruments, and an instrument adapter enables quick-change of instruments during surgery. A custom stylus for a haptic interface enables intuitive and ergonomic telemanipulation of actuated instruments. Experimental results with a force-sensitive phantom eye show that telemanipulated surgery results in reduced forces on the retina compared to manual surgery, and training with the system results in improved performance. Finally, we evaluate operator efficiency with different haptic-interface kinematics for telemanipulated retinal surgery. Surgical procedures of the retina require precise manipulation of instruments inserted through trocars in the sclera. Telemanipulated robotic systems have been developed to improve retinal surgery, but there is not a unique mapping of the motions of the surgeon's hand to the lower-dimensional motions of the instrument through the trocar. We study operator performance during a precision positioning task on a force-sensing phantom retina, reminiscent of telemanipulated retinal surgery, with three common haptic-interface kinematics implemented in software on a PHANTOM Premium 6DOF haptic interface. Results from a study with 12 human subjects show that overall performance is best with the kinematics that represent a compact and inexpensive option, and that subjects' subjective preference agrees with the objective performance results

A continuum robotic platform for endoscopic non-contact laser surgery: design, control, and preclinical evaluation

The application of laser technologies in surgical interventions has been accepted in the clinical domain due to their atraumatic properties. In addition to manual application of fibre-guided lasers with tissue contact, non-contact transoral laser microsurgery (TLM) of laryngeal tumours has been prevailed in ENT surgery. However, TLM requires many years of surgical training for tumour resection in order to preserve the function of adjacent organs and thus preserve the patient’s quality of life. The positioning of the microscopic laser applicator outside the patient can also impede a direct line-of-sight to the target area due to anatomical variability and limit the working space. Further clinical challenges include positioning the laser focus on the tissue surface, imaging, planning and performing laser ablation, and motion of the target area during surgery. This dissertation aims to address the limitations of TLM through robotic approaches and intraoperative assistance. Although a trend towards minimally invasive surgery is apparent, no highly integrated platform for endoscopic delivery of focused laser radiation is available to date. Likewise, there are no known devices that incorporate scene information from endoscopic imaging into ablation planning and execution. For focusing of the laser beam close to the target tissue, this work first presents miniaturised focusing optics that can be integrated into endoscopic systems. Experimental trials characterise the optical properties and the ablation performance. A robotic platform is realised for manipulation of the focusing optics. This is based on a variable-length continuum manipulator. The latter enables movements of the endoscopic end effector in five degrees of freedom with a mechatronic actuation unit. The kinematic modelling and control of the robot are integrated into a modular framework that is evaluated experimentally. The manipulation of focused laser radiation also requires precise adjustment of the focal position on the tissue. For this purpose, visual, haptic and visual-haptic assistance functions are presented. These support the operator during teleoperation to set an optimal working distance. Advantages of visual-haptic assistance are demonstrated in a user study. The system performance and usability of the overall robotic system are assessed in an additional user study. Analogous to a clinical scenario, the subjects follow predefined target patterns with a laser spot. The mean positioning accuracy of the spot is 0.5 mm. Finally, methods of image-guided robot control are introduced to automate laser ablation. Experiments confirm a positive effect of proposed automation concepts on non-contact laser surgery.Die Anwendung von Lasertechnologien in chirurgischen Interventionen hat sich aufgrund der atraumatischen Eigenschaften in der Klinik etabliert. Neben manueller Applikation von fasergeführten Lasern mit Gewebekontakt hat sich die kontaktfreie transorale Lasermikrochirurgie (TLM) von Tumoren des Larynx in der HNO-Chirurgie durchgesetzt. Die TLM erfordert zur Tumorresektion jedoch ein langjähriges chirurgisches Training, um die Funktion der angrenzenden Organe zu sichern und damit die Lebensqualität der Patienten zu erhalten. Die Positionierung des mikroskopis chen Laserapplikators außerhalb des Patienten kann zudem die direkte Sicht auf das Zielgebiet durch anatomische Variabilität erschweren und den Arbeitsraum einschränken. Weitere klinische Herausforderungen betreffen die Positionierung des Laserfokus auf der Gewebeoberfläche, die Bildgebung, die Planung und Ausführung der Laserablation sowie intraoperative Bewegungen des Zielgebietes. Die vorliegende Dissertation zielt darauf ab, die Limitierungen der TLM durch robotische Ansätze und intraoperative Assistenz zu adressieren. Obwohl ein Trend zur minimal invasiven Chirurgie besteht, sind bislang keine hochintegrierten Plattformen für die endoskopische Applikation fokussierter Laserstrahlung verfügbar. Ebenfalls sind keine Systeme bekannt, die Szeneninformationen aus der endoskopischen Bildgebung in die Ablationsplanung und -ausführung einbeziehen. Für eine situsnahe Fokussierung des Laserstrahls wird in dieser Arbeit zunächst eine miniaturisierte Fokussieroptik zur Integration in endoskopische Systeme vorgestellt. Experimentelle Versuche charakterisieren die optischen Eigenschaften und das Ablationsverhalten. Zur Manipulation der Fokussieroptik wird eine robotische Plattform realisiert. Diese basiert auf einem längenveränderlichen Kontinuumsmanipulator. Letzterer ermöglicht in Kombination mit einer mechatronischen Aktuierungseinheit Bewegungen des Endoskopkopfes in fünf Freiheitsgraden. Die kinematische Modellierung und Regelung des Systems werden in ein modulares Framework eingebunden und evaluiert. Die Manipulation fokussierter Laserstrahlung erfordert zudem eine präzise Anpassung der Fokuslage auf das Gewebe. Dafür werden visuelle, haptische und visuell haptische Assistenzfunktionen eingeführt. Diese unterstützen den Anwender bei Teleoperation zur Einstellung eines optimalen Arbeitsabstandes. In einer Anwenderstudie werden Vorteile der visuell-haptischen Assistenz nachgewiesen. Die Systemperformanz und Gebrauchstauglichkeit des robotischen Gesamtsystems werden in einer weiteren Anwenderstudie untersucht. Analog zu einem klinischen Einsatz verfolgen die Probanden mit einem Laserspot vorgegebene Sollpfade. Die mittlere Positioniergenauigkeit des Spots beträgt dabei 0,5 mm. Zur Automatisierung der Ablation werden abschließend Methoden der bildgestützten Regelung vorgestellt. Experimente bestätigen einen positiven Effekt der Automationskonzepte für die kontaktfreie Laserchirurgie

The 2nd International Electronic Conference on Applied Sciences

This book is focused on the works presented at the 2nd International Electronic Conference on Applied Sciences, organized by Applied Sciences from 15 to 31 October 2021 on the MDPI Sciforum platform. Two decades have passed since the start of the 21st century. The development of sciences and technologies is growing ever faster today than in the previous century. The field of science is expanding, and the structure of science is becoming ever richer. Because of this expansion and fine structure growth, researchers may lose themselves in the deep forest of the ever-increasing frontiers and sub-fields being created. This international conference on the Applied Sciences was started to help scientists conduct their own research into the growth of these frontiers by breaking down barriers and connecting the many sub-fields to cut through this vast forest. These functions will allow researchers to see these frontiers and their surrounding (or quite distant) fields and sub-fields, and give them the opportunity to incubate and develop their knowledge even further with the aid of this multi-dimensional network

A flexible access platform for robot-assisted minimally invasive surgery

Advances in Minimally Invasive Surgery (MIS) are driven by the clinical demand to reduce the invasiveness of surgical procedures so patients undergo less trauma and experience faster recoveries. These well documented benefits of MIS have been achieved through parallel advances in the technology and instrumentation used during procedures. The new and evolving field of Flexible Access Surgery (FAS), where surgeons access the operative site through a single incision or a natural orifice incision, is being promoted as the next potential step in the evolution of surgery. In order to achieve similar levels of success and adoption as MIS, technology again has its role to play in developing new instruments to solve the unmet clinical challenges of FAS. As procedures become less invasive, these instruments should not just address the challenges presented by the complex access routes of FAS, but should also build on the recent advances in pre- and intraoperative imaging techniques to provide surgeons with new diagnostic and interventional decision making capabilities. The main focus of this thesis is the development and applications of a flexible robotic device that is capable of providing controlled flexibility along curved pathways inside the body. The principal component of the device is its modular mechatronic joint design which utilises an embedded micromotor-tendon actuation scheme to provide independently addressable degrees of freedom and three internal working channels. Connecting multiple modules together allows a seven degree-of-freedom (DoF) flexible access platform to be constructed. The platform is intended for use as a research test-bed to explore engineering and surgical challenges of FAS. Navigation of the platform is realised using a handheld controller optimised for functionality and ergonomics, or in a "hands-free" manner via a gaze contingent control framework. Under this framework, the operator's gaze fixation point is used as feedback to close the servo control loop. The feasibility and potential of integrating multi-spectral imaging capabilities into flexible robotic devices is also demonstrated. A force adaptive servoing mechanism is developed to simplify the deployment, and improve the consistency of probe-based optical imaging techniques by automatically controlling the contact force between the probe tip and target tissue. The thesis concludes with the description of two FAS case studies performed with the platform during in-vivo porcine experiments. These studies demonstrate the ability of the platform to perform large area explorations within the peritoneal cavity and to provide a stable base for the deployment of interventional instruments and imaging probes

Clinical Considerations for Flexible Access Surgery

The expectation of excellence in health care in modern times continues to be challenged. Government and patients alike continue to demand superior health care with excellent treatment outcomes at minimal expense to their time and convenience. Although surgery is the most definitive treatment option in modern medicine, it can be the most demanding both physically and psychologically. The less invasive the procedure offered the more acceptable it has been shown to be to the patient more often with fewer complications attributed and a faster return to health (1). The positive impact of the minimally invasive concept on the healthcare system has been unfathomable. The domino effect created by the early results from laparoscopic surgery was felt not only across the surgical community but also the medical. Across different specialties, alternative novel therapeutic techniques were devised to overcome problems relating to the large operative procedures which struggled to cross over to the laparoscopic approach. The best example of this is in cardiovascular surgery, where image guided endovascular techniques have overcome the need for many of the once extensive operative procedures including the abdominal aortic aneurysm repair and the coronary bypass procedure. The risks and complications from these operative interventions remain significant and are still performed, though far less frequently than in the past. Selective aneurysms as well as primary coronary events are managed routinely through the endovascular technique with surgery being retained for the complex cases or the non-responders. It seems obvious in hindsight that given the choice of a small 5mm groin incision over a large 30cm open chest or abdominal incision which the public would choose, even with the greater long term benefits sometimes favoring the open approaches. Gastrointestinal endoscopy has the potential to move in the same direction. The use of the endoscope as a surgical tool rather than simply an investigative device has only recently been recognized, promoted through the concept of Natural Orifice Translumenal Endoscopic Surgery (NOTES). The technique aims to provide a cosmetic enhancement to routine surgical procedures by creating the access incision within a natural orifice. The endoscope provides the vision and the biopsy channels in-built are able to guide operative instruments to the target site to enable a therapeutic procedure to be undertaken. However, it would be naïve to believe that in the current state NOTES is anything but a fashionable research technique and far from routine clinical use. However, it’s most superior element, which has the potential to extend the boundaries of surgery aside from all else, is the flexibility of the platform. This thesis provides a detailed investigation into the use of the flexible endoscope as a surgical platform. It defines Flexible Access Surgery (FAS) as an all encompassing surgical technique which utilizes flexible platforms at its heart, describes some novel applications representative as examplars of the technique and explores the significant challenges which would hinder clinical translation. These challenges are described and integrated into two novel enhanced mechatronic flexible access surgical platforms which are further validated and trialed within the pre-clinical in-vivo setting as the future of flexible surgery. The major original contributions of this thesis include the description and definition of the flexible access technique with novel clinical applications. The design, construction and validation of a flexible access box simulator for describing flexible endoscopic navigation within a spatial environment highlighting the challenge this encompasses for many clinicians. The instrumental requirements are explored through the evaluation of the force requirements within the preclinical setting and the instrument refinement both in design and practice that can be adopted to optimize the force delivery particularly when relating to novel flexible platform designs. Finally, the thesis describes the integrated clinical design and validation of two enhanced mechatronic flexible access platforms and describes their clinically driven construction through a series of pre-clinical live in-vivo trials. The evolution of each device is described with performance evaluation and clinical exemplars undertaken. The impact of the results presented within this thesis and the potential for further high impact research is centered on the design and integration of future flexible robotic platforms for minimally invasive surgery. The clinical and mechanical requirements essential for optimal clinical performance will enable designs to be more clinically relevant and ultimately more clinically translatable in the future. Defining these requirements has entailed the use of mapping and sensing the relevant tools which has in turn exposed future potential research avenues to be opened into the perhaps more relevant real time evaluation of the surgical workflow, enabling clinical skills to be more reliably quantified during laparoscopic and endoscopic procedures