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Archivio digitale delle tesi discusse presso l’Università di Pisa

Tesi etd-11032015-130810


Tipo di tesi
Tesi di laurea magistrale
Autore
DINUZZI, GIACOMO
Indirizzo email
g.dinuzzi@virgilio.it
URN
etd-11032015-130810
Titolo
Robotic Hooking System for Floating Lander
Dipartimento
INGEGNERIA CIVILE E INDUSTRIALE
Corso di studi
INGEGNERIA AEROSPAZIALE
Relatori
relatore Prof. Chiarelli, Mario Rosario
Parole chiave
  • floating lander
  • hooking system
  • mechanisms
  • robotic arm
  • structure
Data inizio appello
01/12/2015
Consultabilità
Completa
Riassunto
Abstract
Exploration of planets’ satellites and other celestial bodies such as comets and asteroids is lately becoming of interest either for scientific purpose or for commercial exploitation. This thesis work propose a possible robotic hooking system in order to stabilize a floating lander which should make some samples acquisition on outer planet’s satellite.
Analysis begin from some already existing mission proposals which involve exploration of Titan, Saturn’s largest moon. Since Titan surface is widely covered by liquid methane lakes, all mission proposals include floating lander which should be capable of travelling on lakes’ surface. Because of scientific interest either in liquid samples analysis or solid shoreline analysis, one can think about a possible hooking system to be deployed close to shoreline rocks, in order to make possible solid samples acquisition from cost line. Then Titan environment has been analysed, taking into account wind and waves to design a proper hooking system. At the beginning two possible hooking mechanism candidates have been considered, harpoon mechanism and robotic arms, identifying pros and cons for both configurations. Various considerations have led to the choice of robotic arms system for hooking realization. Once more suited hooking system has been chosen for this purpose, some computational analysis has been carried out in order to find a proper arm cross section capable of resisting under loading conditions. Hooking problem has been analysed from a displacement point of view, thinking of not being capable of lowering vertical displacement imposed by waves motion. A simplified two dimensional model has been used at first and once cross section candidates have been identified, two dimensional results have been validated with a three dimensional model. Later on, hooking mechanism choice have been taken into account more in detail. Even for hooking mechanism itself, two different possible hooking mechanisms have been considered first, suction cups-based mechanism and microspines-based one. From dimension and adaptability considerations microspines-based mechanism has been chosen. Then, hooking mechanism dimension and mechanical parts design have been produced. Effects of arms’ motion on lander stability have been analyse too, leading to proposed deployment pattern which maintains lander within acceptable values of tilting angles. At the end of thesis work hooking mechanism model have been validated with fatigue analysis in order to ensure proper functioning under repeated cycles of loading.
Finally, some considerations about future work to be done have been proposed, in order to improve current work and to further develop presented preliminary analysis. A section about similar robotic mechanism has been added at the end of the thesis for sake of completeness and to show other possible applications to microspines technology.
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