Experimental studies of tail shapes for hummingbird-like flapping wing micro air vehicles

The stability of flying of a hummingbird-like flapping-wing micro air vehicle (MAV) has been challenging. In this paper, experimental studies are reported on the tail shapes of hummingbird-like flapping-wing MAVs, since tails play an important role in-flight stability. Dynamics parameters of hummingbird tails are firstly studied and evaluated. Then man-made tails inspired by the natural hummingbirds are designed, manufactured and optimized for experimental tests. The results show that lift generated by the tail is independent of a fan angle, whereas the pitch moment is related to the fan angle. Further, the tail can be applied to stabilising hovering twin-wing flapping wing MAVs

Developing technological fluency through creative robotics

Children have frequent access to technologies such as computers, game systems, and mobile phones (Sefton-Green, 2006). But it is useful to distinguish between engaging with technology as a 'consumer' and engaging as a 'creator' or designer (Resnick & Rusk, 1996). Children who engage as the former can use technology efficiently, while those who engage as the latter are creative and adaptive with technology. The question remains of how best to encourage movement along this continuum, towards technological fluency. This study defines three habits of mind associated with fluent technology engagement [(1) approaching technology as a tool and a creative medium, (2) understanding how to engage in a design process, and (3) seeing oneself as competent to engage in technological creativity], and examines the implementation of a learning environment designed to support them. Robot Diaries, an out-of-school workshop, encourages middle school girls to explore different ways of expressing and communicating with technology, to integrate technology with personal or fictional storytelling, and to adapt their technical knowledge to suit their own projects and ideas. Two research purposes guide this study. The first is to explore whether Robot Diaries, which blends arts and engineering curricula, can support multiple pathways to technological fluency. The second purpose is to develop and test a set of instruments to measure the development of technological fluency. Robot Diaries was implemented with a group of seven home-schooled girls between the ages of 9 and 14. Instructors from a home school enrichment program ran the workshop. The study utilized a mixed methods approach. Analysis suggests two distinct patterns of engagement in Robot Diaries are possible - an engineering focus (characterized by attention to the structure and function of the robot) and an artistic focus (characterized by attention to the robot's representational capacity). The ability to support and sustain multiple levels of participation is an important quality in a workshop designed to broaden engagement in technology exploration activities. Pre-post assessments suggest changes in confidence and (to a lesser extent) knowledge. This study has implications for the design of learning environments to support technological fluency, and for measuring this construct

Exploring the biofluiddynamics of swimming and flight

cum laude graduation (with distinction

Optimizing the structure and movement of a robotic bat with biological kinematic synergies

In this article, we present methods to optimize the design and flight characteristics of a biologically inspired bat-like robot. In previous, work we have designed the topological structure for the wing kinematics of this robot; here we present methods to optimize the geometry of this structure, and to compute actuator trajectories such that its wingbeat pattern closely matches biological counterparts. Our approach is motivated by recent studies on biological bat flight that have shown that the salient aspects of wing motion can be accurately represented in a low-dimensional space. Although bats have over 40 degrees of freedom (DoFs), our robot possesses several biologically meaningful morphing specializations. We use principal component analysis (PCA) to characterize the two most dominant modes of biological bat flight kinematics, and we optimize our robot’s parametric kinematics to mimic these. The method yields a robot that is reduced from five degrees of actuation (DoAs) to just three, and that actively folds its wings within a wingbeat period. As a result of mimicking synergies, the robot produces an average net lift improvesment of 89% over the same robot when its wings cannot fold

Topology Optimization Design of Monolithic 3D Printed Compliant Mechanisms for Bio-Inspired Actuation Systems of FWMAVs

L'obiettivo principale della presente tesi è esplorare la capacità di un approccio di progettazione combinato che sfrutta contemporaneamente i vantaggi dell'analisi FEM, dei meccanismi flessibili, dell'ottimizzazione topologica e delle tecnologie di stampa 3D. Oggigiorno la continua ricerca di prodotti più leggeri e semplici è diffusa in ogni realtà industriale che mira a mantenere la competitività. Allo stesso tempo, sebbene la riduzione del numero di componenti di un prodotto sia un obiettivo auspicabile, anche la complessità dei design tende a crescere costantemente.In questo contesto, diventa significativa l'implementazione di un processo di progettazione atto a combinare diversi strumenti ingegneristici, al fine di soddisfare tutte le specifiche di prodotto richieste e di sviluppare prodotti innovativi con migliori prestazioni. In particolare, questa ricerca mira a evidenziare le criticità e le potenzialità dell'implementazione di meccanismi flessibili tramite ottimizzazione topologica nello sviluppo di strutture monocomponente stampabili in 3D per l'attuazione di Flapping Wing Micro Air Vehicles (FWMAV) bio-ispirati. Alla ricerca di un approccio moderno alla progettazione, i suddetti strumenti ingegneristici sono stati integrati con l’efficacia delle soluzioni offerte dalla natura, sfruttando l’idea di reingegnerizzare la flessibilità naturale insita nelle strutture biologiche.È stata presa in considerazione anche l'opportunità di personalizzare il design, in modo da fornire una potenziale fonte di ispirazione per una diversa gamma di applicazioni.The main focus of the present dissertation is to explore the capability of a combined design approach that exploits at once the advantages of FEM analysis, Compliant Mechanisms, Topology Optimization and 3D Printing Technologies. Nowadays the continuous pursuit of lighter and simpler products is widespread in any industrial company aiming to maintain competitivity. At the same time, while part-count reduction of an item is a desirable target, also the complexity of designs tends to be ever-growing.In this context, the implementation of a design process suitable to combine different engineering tools becomes significant, in order to fulfill all the required product specifications and to develop innovative products with increased performances. In particular, this research aims to highlight the critical issues and the potentialities of implementing topology optimized Compliant Mechanisms in the development of monolithic 3D printable structures for the actuation of bio-inspired Flapping Wing Micro Air Vehicles (FWMAVs). Seeking a modern approach to design, the aforementioned engineering design tools were integrated with the effectiveness of solutions offered by nature, exploiting the idea of re-engineering the natural flexibility inherent in biological structures.The opportunity of tailoring the design was taken into account too, in order to provide a potential source of inspiration for a different range of applications

Learning and animal movement

Authors acknowledge the following grants for supporting this research: NSERC Discovery (ML and MA-M), NSF DMS-1853465 (WF and EG), and Canada Research Chairs Program (ML and MA-M).Integrating diverse concepts from animal behavior, movement ecology, and machine learning, we develop an overview of the ecology of learning and animal movement. Learning-based movement is clearly relevant to ecological problems, but the subject is rooted firmly in psychology, including a distinct terminology. We contrast this psychological origin of learning with the task-oriented perspective on learning that has emerged from the field of machine learning. We review conceptual frameworks that characterize the role of learning in movement, discuss emerging trends, and summarize recent developments in the analysis of movement data. We also discuss the relative advantages of different modeling approaches for exploring the learning-movement interface. We explore in depth how individual and social modalities of learning can matter to the ecology of animal movement, and highlight how diverse kinds of field studies, ranging from translocation efforts to manipulative experiments, can provide critical insight into the learning process in animal movement.Publisher PDFPeer reviewe