Anthropomorphic surgical system for soft tissue robot-assisted surgery

Over the past century, abdominal surgery has seen a rapid transition from open procedures to less invasive methods such as laparoscopy and robot-assisted minimally invasive surgery (R-A MIS). These procedures have significantly decreased blood loss, postoperative morbidity and length of hospital stay in comparison with open surgery. R-A MIS has offered refined accuracy and more ergonomic instruments for surgeons, further minimising trauma to the patient.This thesis aims to investigate, design and prototype a novel system for R-A MIS that will provide more natural and intuitive manipulation of soft tissues and, at the same time, increase the surgeon's dexterity. The thesis reviews related work on surgical systems and discusses the requirements for designing surgical instrumentation. From the background research conducted in this thesis, it is clear that training surgeons in MIS procedures is becoming increasingly long and arduous. Furthermore, most available systems adopt a design similar to conventional laparoscopic instruments or focus on different techniques with debatable benefits. The system proposed in this thesis not only aims to reduce the training time for surgeons but also to improve the ergonomics of the procedure.In order to achieve this, a survey was conducted among surgeons, regarding their opinions on surgical training, surgical systems, how satisfied they are with them and how easy they are to use. A concept for MIS robotic instrumentation was then developed and a series of focus group meetings with surgeons were run to discuss it. The proposed system, named microAngelo, is an anthropomorphic master-slave system that comprises a three-digit miniature hand that can be controlled using the master, a three-digit sensory exoskeleton. While multi-fingered robotic hands have been developed for decades, none have been used for surgical operations. As the system has a human centred design, its relation to the human hand is discussed. Prototypes of both the master and the slave have been developed and their design and mechanisms is demonstrated. The accuracy and repeatability of the master as well as the accuracy and force capabilities of the slave are tested and discussed

SUPPORTING ENGINEERING DESIGN OF ADDITIVELY MANUFACTURED MEDICAL DEVICES WITH KNOWLEDGE MANAGEMENT THROUGH ONTOLOGIES

Medical environments pose a substantial challenge for engineering designers. They combine significant knowledge demands with large investment for new product development and severe consequences in the case of design failure. Engineering designers must contend with an often-chaotic environment to which they have limited access and familiarity, a user base that is difficult to engage and highly diverse in many attributes, and a market structure that often pits stakeholders against one another. As medical care in general moves towards personalized models and surgical tools towards less invasive options emerging manufacturing technologies in additive manufacturing offer significant potential for the design of highly innovative medical devices. At the same time however these same technologies also introduce yet more challenges to the design process. This dissertation presents a knowledge-based approach to addressing the existing and emerging challenges of medical device design. The approach aims to address these challenges using knowledge captured in a suite of modular ontologies modeling knowledge domains that must be considered in medical device design. These include ontologies for understanding clinical context, human factors, regulation, enterprise, and manufacturability. Together these ontologies support design ideation, knowledge capture, and design verification. These ontologies are subsequently used to formulate a comprehensive knowledge framework for medical device design, and to enable an innovative design process. Case studies analyzing the design of surgical tools in several medical specialties are used to assess the capabilities of this approach

Molecular phylogeny of horseshoe crab using mitochondrial Cox1 gene as a benchmark sequence

An effort to assess the utility of 650 bp Cytochrome C oxidase subunit I (DNA barcode) gene in delineating the members horseshoe crabs (Family: xiphosura) with closely related sister taxa was made. A total of 33 sequences were extracted from National Center for Biotechnological Information (NCBI) which include horseshoe crabs, beetles, common crabs and scorpion sequences. Constructed phylogram showed beetles are closely related with horseshoe crabs than common crabs. Scorpion spp were distantly related to xiphosurans. Phylogram and observed genetic distance (GD) date were also revealed that Limulus polyphemus was closely related with Tachypleus tridentatus than with T.gigas. Carcinoscorpius rotundicauda was distantly related with L.polyphemus. The observed mean Genetic Distance (GD) value was higher in 3rd codon position in all the selected group of organisms. Among the horseshoe crabs high GC content was observed in L.polyphemus (38.32%) and lowest was observed in T.tridentatus (32.35%). We conclude that COI sequencing (barcoding) could be used in identifying and delineating evolutionary relatedness with closely related specie

Crab and cockle shells as heterogeneous catalysts in the production of biodiesel

In the present study, the waste crab and cockle shells were utilized as source of calcium oxide to transesterify palm olein into methyl esters (biodiesel). Characterization results revealed that the main component of the shells are calcium carbonate which transformed into calcium oxide upon activated above 700 °C for 2 h. Parametric studies have been investigated and optimal conditions were found to be catalyst amount, 5 wt.% and methanol/oil mass ratio, 0.5:1. The waste catalysts perform equally well as laboratory CaO, thus creating another low-cost catalyst source for producing biodiesel. Reusability results confirmed that the prepared catalyst is able to be reemployed up to five times. Statistical analysis has been performed using a Central Composite Design to evaluate the contribution and performance of the parameters on biodiesel purity

Simple and low-cost manufacturing of customisable drug delivery devices and flexible sensors for biomedical applications

In recent years, 3D printing technologies have been adopted into the medical and pharmaceutical industry for the fabrication of personalised medicines, oral dosage forms, medical implants, medical devices, tissue engineering applications, and many more. However, the use of 3D printing, in particular the low-cost Fused Deposition Modelling (FDM) 3D printing technique, has been limited due to the limited number of biocompatible materials suitable for pharmaceutical and biomedical applications. In this study, the FDM 3D printing technique was being explored for the fabrication of pharmaceutical products as it is the most widely available and easily accessible 3D printing technology. In order to improve the usability of FDM 3D printing for pharmaceutical and biomedical applications, the studies to fabricate several different biocompatible filaments composition that can be used for drug loading were carried out. Firstly, filaments made of several pharmaceutical grade polymers were being developed using hot-melt extrusion (HME). Three types of biocompatible polymeric filaments have been developed. They are (Polylactic Acid) PLA-based, (Hydroxypropyl Cellulose) HPC-based and (Polycaprolactone) PCL-based. These filaments were added with a plasticiser, polyethylene glycol (PEG), to improve their processability and physicochemical properties of the produced filaments so that they can used in an FDM 3D printer. The HPC-based filaments were loaded with a model drug, theophylline, that exhibits poor aqueous solubility, whereas the PCL-based filaments were loaded with a readily soluble model drug, metformin. The studies showed that the filaments were effective in sustaining the release of both drug, and the sustain release properties of the filaments can be adjusted by altering the composition of the polymers. The studies showed that the HME technology is very compatible with FDM 3D printing as it is able to produce 3D printable filaments by mixing different polymeric materials. The filaments can also be loaded with a desired drug at a required dose to allow the 3D printing of drug delivery systems. This technique allows the fabrication of personalised drug delivery systems in-house. It can be beneficial for clinics and hospitals in remote areas as the lead times can be reduced when in-house fabrication is possible. The ability to fabricate personalised medicines at hand also means that the dose can drug release patterns can be altered for the patients at any point of time when required. Apart from that, this technique can change way medicines are transported and stored, which could potentially help save cost on transportation and inventory. In addition to medicines, the FDM 3D printing technique can also be used to produce other personalised drug delivery systems such as microneedles, braces and implants of various shapes due to the flexibility of the 3D printing process. The other aspect of this research was on the fabrication of biomedical sensors that can potentially be integrated with the 3D printed drug delivery systems to form a smart drug delivery device. The idea of smart drug delivery device is that it is capable of continuous monitoring the health of a patient and then administer drug to the patient whenever it is required. The development of such smart medical devices has been one of the hottest interests in the biomedical sector. One of the main issues with such technologies is the high cost which has caused the technologies to be not so affordable for many people. Therefore, the studies to fabricate some simple biomedical sensors such as a temperature sensor and a glucose sensor using simple and cost-effective manufacturing technique were being explored. The fabrication techniques used are FDM 3D printing and a thin-film fabrication technique that involves deposition of material using a thermal evaporator. Low-cost manufacturing techniques were being explored in order to help reduce manufacturing cost which could help improve the affordability of such technologies. The fabricated temperature and glucose sensors exhibit great stability in performance and mechanical flexibility. The flexibility allows the sensors to be conformable to curved surfaces such as the skin. Hence, the sensors are suitable to be used as a wearable device or integrated into some other medical devices to form a smart medical device