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The goal of this research is to develop the prototype of a tactile sensing platform for anthropomorphic manipulation research. We investigate this problem through the fabrication and simple control of a planar 2-DOF robotic finger inspired by anatomic consistency, self-containment, and adaptability. The robot is equipped with a tactile sensor array based on optical transducer technology whereby localized changes in light intensity within an illuminated foam substrate correspond to the distribution and magnitude of forces applied to the sensor surface plane. The integration of tactile perception is a key component in realizing robotic systems which organically interact with the world. Such natural behavior is characterized by compliant performance that can initiate internal, and respond to external, force application in a dynamic environment. However, most of the current manipulators that support some form of haptic feedback either solely derive proprioceptive sensation or only limit tactile sensors to the mechanical fingertips. These constraints are due to the technological challenges involved in high resolution, multi-point tactile perception. In this work, however, we take the opposite approach, emphasizing the role of full-finger tactile feedback in the refinement of manual capabilities. To this end, we propose and implement a control framework for sensorimotor coordination analogous to infant-level grasping and fixturing reflexes. This thesis details the mechanisms used to achieve these sensory, actuation, and control objectives, along with the design philosophies and biological influences behind them. The results of behavioral experiments with a simple tactilely-modulated control scheme are also described. The hope is to integrate the modular finger into an %engineered analog of the human hand with a complete haptic system.

Masters Research - Masters of Philosophy / INTRODUCTION: Level III dosimetric intercomparison studies test the entire radiotherapy patient treatment chain from diagnostic imaging to treatment delivery and verification imaging at multiple radiotherapy centres. The anthropomorphic phantom employed in an intercomparison needs to meet specific criteria including portability, tissue equivalence and accommodation of radiation detectors to ensure clinical relevance and dosimetric accuracy. The proposition that a purpose-built phantom can encompass all the attributes necessary for precise Level III dosimetric intercomparisons for prostate cancer is the premise of this body of work. METHODS: Organ outlines were generated from a human computed tomography image set and incorporated into the phantom design to replicate human anatomy as closely as possible. Twenty-five points of interest were located throughout the dataset to identify where point-dose values could be measured with thermoluminescence dosimeters. The centre of the prostate was identified as the location for measurement with a small-volume ionization chamber. The materials used in this phantom were tested against water to determine relative attenuation, density and Hounsfield Units. Three materials were chosen to mimic bone, organs, and a backfill material and the phantom was manufactured using modern prototyping techniques into five separate coronal slices. Time lines and resource requirements for the phantom design and manufacture were recorded. The ability of the phantom to mimic the entire treatment chain was tested at the Calvary Mater Newcastle Hospital. RESULTS: The phantom CT images indicated the densities and organ geometries were comparable to the original patient. The phantom proved simple to load for dosimetry and rapid to assemble. Measurements indicated the reproducibility to be in the order of 1% for the ionization chamber measurement and within 3% for thermoluminescence dosimeters. Due to heat release during manufacture, small airgaps were present throughout the phantom producing artifacts on lateral images. The overall cost for production of the prototype phantom was comparable to other commercial anthropomorphic phantoms ($AU45,000). The phantom was shown to be suitable for use as a “patient” to mimic the entire treatment chain for typical external beam radiotherapy for prostate and rectal cancer. Outlining of relevant structures by a radiation oncologist was uncomplicated and the computerised treatment plan compared well with the dose measured using ionisation chambers and thermoluminescence dosimeters. DISCUSSION & CONCLUSIONS: The phantom constructed for the present study incorporates all characteristics necessary for accurate Level III intercomparison studies and will be an effective tool for an intercomparison of pelvic treatments in Australasia. These results may benefit analysis of outcomes for prostate cancer treatments, especially in the clinical trial environment. It will be of significant interest in the future to use the phantom to assess advanced radiotherapy delivery techniques such as Intensity Modulated Radiation Therapy (IMRT).

Master of Science / Department of Mechanical and Nuclear Engineering / William L. Dunn / Neutron dosimeters measure neutron doses but portable, real time, high efficiency, and gamma insensitive neutron dosimeters are not commonly available. Characterization of a newly invented neutron dosimeter, based on perforated semiconductor neutron detectors (SNDs) whose perforations are filled with neutron reactive material, was the main purpose of this research study. The characterization procedure was performed by both simulation and experiment. The Monte Carlo N-Particle (MCNP) transport code was used to model a boron-filled dosimeter and to study the responses when the dosimeter was located on the surfaces of a water phantom and an anthropomorphic phantom for parallel beams of neutrons having various energy spectra. A pair of detectors was modeled: one bare and one Cd-filtered. Dosimeter responses were normalized for a beam that would produce 1 mSv ambient dose equivalent if incident on the ICRU sphere phantom. Dosimeter responses were estimated at different positions on the torso and it was found that the responses are relatively insensitive to the placement on the torso. For 100% efficient detectors and for beam with a Watt spectrum incident from front to back of the phantom, the bare detector produces about 140 counts per [Mu]Sv and the Cd-filtered detector produces about 80 counts per [Mu]Sv. The experimental characterization study involves observing SND counts with the dosimeter placed on an anthropomorphic torso phantom and determining the corresponding neutron dose. A TLD pair method was used to determine the neutron dose on the surface of the phantom. The neutron reactive material of the dosimeter was [superscript]6LiF, which is different from that assumed for the modeled dosimeter. A bare dosimeter response collected over 10 min was 25113 [plus or minus] 158 counts and the corresponding neutron dose was measured to be 2.57 mSv. The Cd-filtered dosimeter response collected over 10 min was 23886 [plus or minus] 155 counts and the corresponding neutron dose was measured to be 2.32 mSv. The neutron dosimeters are capable of detecting doses in the [Mu]Sv range and above, and are anticipated to provide direct read-out in dose units in future using count-to-dose conversion factors for bare and Cd-filtered SNDs.

This thesis investigates the work of Nikolaas (Niko) Tinbergen and his students, often known as the Tinbergians. Based on extensive archival research, and particularly on intensive study of fieldnotes – a resource largely untouched in previous historical enquiry – I throw new light on the scientific practices both of Tinbergen himself and the practices of individual students of his, including the relationship between research in the field and in the laboratory and the relationship between that research and the Tinbergians representation of their science, both to scientific and lay audiences. Chapter one investigates Tinbergen's own background, and his writings on method and practice. This included a commitment to studying 'natural' behaviour, which led them to be wary of experimental methods that might distort such behaviour. Tinbergen's idea of the 'ethogram' – a complete listing of the behavioural repertoire of a species – is here linked to earlier interest in comparative anatomy as a means of elucidating evolutionary relationships Contrary to the work of Eileen Crist, who argues that ethologist concern to produce mechanomorphic descriptions of behaviour led them to see their animals as machines, I show that the fieldnotes regularly included anthropomorphic description, which only later was excised in writing up scientific publications where mechanistic description and a programmatic rejection of anthropomorphism were the norm. The backgrounds of many of Tinbergen's contemporaries and students was considered in the first half of chapter two, and showed that almost all members of the school had a background in amateur natural history and strong personal and aesthetic affection for the animals they studied. The early fieldwork of the Tinbergians is examined in more detail in the second half of the chapter. This considers the work of two of Tinbergen's students: Robert Hinde and Martin Moynihan. Hinde's work is shown to be transitional between earlier approaches to animal behaviour and the more systematic methodology promoted by Tinbergen, while Moynihan's work instantiated a particularly pure expression of early Tinbergian ideals. Tinbergen's Oxford laboratory is the subject of chapter three, looking in particular at how 'natural' behaviour was studied in an artificial environment. I look at the work of Desmond Morris, Margaret Bastock (later Manning) and J. Michael (Mike) Cullen. Morris's work reproduced field techniques of intensive close observation of behaviour in the laboratory. Bastock's work, largely overlooked by previous historians, showed interest in behaviour genetics. Cullen's work illustrates the difficulties of studying natural behaviour under laboratory conditions, and emphasises the value that Tinbergians placed on direct observation over other possible recording techniques. I then proceed to a more general consideration of the relationship between laboratory and field in the early years of the Tinbergen school. Change over time is the theme of chapter four. Many of the early methodological commitments of the school were subsequently abandoned as the observation-led approach to behaviour gave way to a more explicitly theory-led and interventionist concern with causation, development, evolution and function. This was apparent both in the field and in the laboratory, and even included the occasional adoption of vivisection – a method dramatically at odds with the ethos of the early Tinbergen school. The final chapter investigates how Tinbergen and others of his school communicated their work to amateur audiences, and shows that in some instances the anthropomorphic observations excluded for their scientific writings reappear in these more popular communications. I then link this to the Tinbergen school's longstanding interest in human behaviour. The thesis is supplemented by a conclusion, and two appendices one listing the students studied in the thesis, and the other listing as many of Tinbergen's students as I can identify with surety.

Anthropomorphic phantoms are commonly used for testing radiation fields without the need to expose human subjects. One of the most widely known is RANDO phantom. This phantom is used primarily for medical X-ray applications, but a similar design known as "MATROSHKA" is now being used for space research and exposed to heavy ion irradiations from the Galactic environment. Since the radiation field in the phantom should respond in a similar manner to how it would act in human tissues and organs under an irradiation, the tissue substitute chosen for soft tissue and the level of complexity of the entire phantom are crucial issues. The phantoms, and the materials used to create them, were developed mainly for photon irradiations and have not been heavily tested under the conditions of heavy ion exposures found in the space environment or external radiotherapy. The Particle and Heavy-Ion Transport code System (PHITS) was used to test the phantoms and their materials for their potential as human surrogates for heavy ion irradiation. Stopping powers and depth-dose distributions of heavy charged particles (HCPs) important to space research and medical applications were first used in the simulations to test the suitability of current soft tissue substitutes. A detailed computational anthropomorphic phantom was then developed where tissue substitutes and ICRU-44 tissue could be interchanged to verify the validation of the soft tissue substitutes and and determine the required level of complexity of the entire phantom needed to achieve a specified precision as a replacement of the human body. The materials tested were common soft tissue substitutes in use and the materials which had a potential for the soft tissue substitute. Ceric sulfate dosimeter solution was closest to ICRU-44 tissue; however, it was not appropriate as the phantom material because it was a solution. A150 plastic, ED4C (fhw), Nylon (Du Pont Elvamide 8062), RM/SR4, Temex, and RW-2 were within 1% of the mean normalized difference of mass stopping powers (or stopping powers for RW-2) when compared to the ICRU-44 tissue, and their depth-dose distributions were close; therefore, they were the most suitable among the remaining solid materials. Overall, the soft tissue substitutes which were within 1% of ICRU-44 tissue in terms of stopping power produced reasonable results with respect to organ dose in the developed phantom. RM/SR4 is the best anthropomorphic phantom soft tissue substitute because it has similar interaction properties and identical density with ICRU-44 tissue and it is a rigid solid polymer giving practical advantages in manufacture of real phantoms.

Un des freins majeurs au développement de la manipulation d'objet avec une main robotisée est sans aucun doute leur fragilité. C'est l'une des raisons pour laquelle un système bras-main anthropomorphe, extrêmement robuste, est développé au centre de robotique et de mécatronique de DLR. Le système est unique à la fois par sa complexité, utilisant 52 moteurs et plus de200 capteurs, ainsi que par ses capacités dynamiques. En effet, ce nouveau système a la particularité d'être mécaniquement flexible ce qui offre la possibilité de stocker de l'énergie à court terme et remplit ainsi deux fonctions essentielles pour un robot humanoïde: les impacts sont filtrés et les performances dynamiques sont augmentées.Dans cette thèse, on se concentre plus particulièrement sur la main. Elle dispose de 19 degrés de liberté dont chacun est actionné par deux tendons flexibles antagonistes. La rigidité des tendons étant non linéaire il est possible, tout comme peut le faire l'être humain, de co-contracter les <<muscles>> et donc d'ajuster la rigidité des doigts afin de s'adapter au mieux aux tâches à effectuer. Cependant, cette flexibilité entraine de nouveau défis de modélisation et de contrôle. L'état de l'art se concentre majoritairement sur le problème de la répartition des forces internes ou du contrôle d'articulation flexible mais peu de travaux considèrent les deux problèmes simultanément.Le travail présenté dans la première partie de la thèse se concentre sur la modélisation de la main et du poignet. Les problématiques spécifiques aux systèmes actionnés par des tendons, tels que les matrices de couplage et l'estimation du déplacement des articulations à partir du déplacement des tendons, sont étudiées.La seconde partie se concentre sur le contrôle d'articulations actionnées par des tendons flexibles antagonistes. Les problèmes de distribution des forces internes et de correction de la rigidité perçue par l'utilisateur sont présentés.Des approches de contrôle linéaire et non linéaire sont utilisées et des expériences sont réalisées pour comparer ces approches. En particulier, il est montré que le <<backstepping>>, une méthode de contrôle non linéaire peut être utilisée et permet d'obtenir le comportement d'impédance souhaité tout en garantissant la stabilité en boucle fermée. / One of the major limitations of object manipulation with a robotic hand is the fragility of the hardware.This is one of the motivations for developing the new anthropomorphic and extremely robust Hand Arm System at the robotics and mecatronics center of DLR.The system is unique in terms of complexity, with 52 motors and more than 200 sensors, and also in terms of dynamics.Indeed, the system is mechanically compliant, thus offers the possibility to store and release energy, thereby providing two essential functions: The impacts are filtered and the dynamics are enhanced.This thesis focuses on the hand. It has 19 degrees of freedom, each being actuated by two flexible antagonistic tendons. Because the stiffnes of the tendons is not linear, it is possible to adjust the mechanical stiffness of the joints, similar to the co-contraction of human muscles, in order to adapt to a task. However, the stiffness adjustability rises new challenges in modeling and control. The state of the art usually focuses on the problems of tendon-driven systems or flexible joint robots but seldomly both simultaneously.In the first part, the modeling of the hand and the wrist is conducted. Several problems specific to tendon-driven systems are presented, such as the coupling matrices and the joint position estimation based on the tendon displacement. The second part focuses on the control of a single joint actuated by two flexible tendons. The distribution of the tendon forces and the correction of the effective stiffness are reported. Linear and nonlinear approaches are used and multiple experiments are realised to compare them. The major result is that the backstepping, a nonlinear control method, can be used and provides the desired impedance behavior while guaranting closed-loop stability.

Robots should offer a human-like level of dexterity when handling objects if humans are to be replaced in dangerous and uncertain working environments. This level of dexterity for human-like manipulation must come from both the hardware, and the control. Exact replication of human-like degrees of freedom in mobility for anthropomorphic robotic hands are seen in bulky, costly, fully actuated solutions, while machine learning to apply some level of human-like dexterity in underacted solutions is unable to be applied to a various array of objects. This thesis presents experimental and theoretical contributions of a novel neuro-fuzzy control method for dextrous human grasping based on grasp synergies using a Human Computer Interface glove and upgraded haptic-enabled anthropomorphic Ring Ada dexterous robotic hand. Experimental results proved the efficiency of the proposed Adaptive Neuro-Fuzzy Inference Systems to grasp objects with high levels of accuracy.

This study was conducted to investigate the empathy between human chatbot interactions amongcomputer science students at Uppsala University, Sweden. This was done by exploring howparticipants perceive anthropomorphic chatbots as machines or humans, the existence of verbalabuse during human chatbot interactions, and the expectation of chatbot helpfulness dependingon gender dynamics. A semi-structured interview methodology with five students was conductedfor qualitative data collection. The collected data was manually analyzed using thematic analysis.The results of this study found that there is empathy in human chatbot interaction, regardless ofwhether participants perceive anthropomorphic chatbots as humans or machines. However, thelevel of empathy is generally low as participants frustrate when they are dissatisfied with theresponse of chatbots and exit the chatbots without expressing their frustration, and they usuallyforget their frustration and come again with other questions another time. The study also showsthat participants might expect more help and politeness if chatbots are more likely to be female.