Marco Dolci

Analysis of alternative energy harvesting methods to power atmospheric robotic explorers on Jupiter

WindBots is a NIAC funded concept for a long-duration atmospheric robot explorer targeting the region between 0.3 bar and 10 bar on Jupiter. The WindBot would explore this region, which extends from 15km above to 125km below the reference surface at 1 bar. Proposed WindBot mission scenarios include a glider which would use updrafts to gain altitude before gliding to find another updraft, mimicking the action of soaring birds such as frigate birds. In another mission scenario, a balloon-like WindBot would use buoyancy to maintain altitude within its operational region. An important requirement of a WindBot is survival with energy obtained in-situ to provide power for the 30–50W avionic payload envisioned for the mission. The solar intensity below Jupiters clouds is small and a solar solution as well as a nuclear solution have been ruled out from this study. This paper analyzes methods of energy generation and harvesting in Jupiters atmosphere and offers a comparison of the relative power densities. Wind, thermal, and magnetic energy, as well as other modalities, are sources of energy for a WindBot to transform into mechanical or electrical energy. Mechanisms evaluated include vibration harvesting and turbine technologies to utilize small-scale wind velocity gradients. Natural atmospheric thermal and pressure gradients may be tapped to provide power to a WindBot. The possibility of inductive generation using Jupiters strong magnetic field is also considered. Finally, these methods are evaluated on their power density and applicability to proposed WindBot designs.

Robotic gripper for payload capture in low Earth orbit

The consensus to a study phase for an Intermediate eXperimental Vehicle (IXV) successor, a preoperational vehicle called Space Reusable Integrated Demonstrator for European Return (SPACE RIDER), has been recently enlarged, as approved during last EU Ministerial Council. One of the main project tasks consists in developing SPACE RIDER to conduct on orbit servicing activity with no docking. SPACE RIDER would be provided with a robotic manipulator system (arm and gripper) able to transfer cargos, such as scientific payloads, from low Earth orbiting platforms to the SPACE RIDER cargo bay. The platform is a part of a space tug designed to move small satellites and other payloads from Low Earth Orbit to Geosynchronous Equatorial Orbit and vice versa. A study on this robotic technology is here presented. This research is carried out by Politecnico di Torino and Thales Alenia Space Italy. The system configuration of the robotic manipulator is first described in terms of volumes and masses. The considered housing cargo bay requirements in terms of volume (< 100 l) and mass (< 50 kg) combined with the required overall arm dimensions (4 m length), and mass of the cargo (5–30 kg) force to developing an innovative robotic manipulator with the task-oriented end-effector. It results in a 7df arm to ensure a high degree of dexterity and a dedicated end-effector designed to grasp the cargo interface. The gripper concept here developed consists in a multi-finger hand able to lock both translational and rotational cargo degrees of freedom through an innovative under-actuation strategy to limit its mass and volume. A configuration study on the cargo handle interface has also been performed together with some computer-aided design models and multibody analysis of the whole system to prove its feasibility. Finally, the concept of system control architecture is defined.

WindBots: A Concept for Persistent In Situ Science Explorers for Gas Giants

Visible to the naked eye, the gas giants Jupiter and Saturn have been known to astronomers since antiquity. In the modern times much was learned about them, and yet so much remains to be learned. They are made almost entirely of hydrogen and helium, they have no hard surface to land to; their low temperature atmospheres are characterized by strong winds, at least in the observed upper atmosphere. What we know about them comes from remote sensing—yet their clouds impede deeper observation through remote sensing. We also have, in a singular case, data transmitted by a robotic probe that descended through the Jovian atmosphere. We need more of these probes, to confirm the models we formed about these planets, and to discover new phenomena below their clouds. This chapter examines mission concept alternatives in which robotic craft operate in the atmospheres of gas giants, for long duration, and using energy derived from local sources. In a preferred scenario these Wind Robots (WBs), with high mobility and autonomy compared to passive balloons, would operate in the Jovian atmosphere above and below the region of clouds, between 0.3 and 10 bar, for a year-long duration mission, in strong (potentially turbulent) winds. In an example, notional mission, a WB would operate in the eyewall of the Great Red Spot, using the high wind and updrafts of the anticyclone, as well as horizontal gusts. Both naturally buoyant and winged solutions, as well as hybrids of the two, are determined possible. A Network of WBs could measure wind speeds, temperatures, and atmospheric composition simultaneously, at multiple locations.

Windbots: An investigation of potential solutions for Jupiter-based aerostatic robotic explorers

The purpose of this paper is to investigate robotic mobility solutions for long-duration (∼years), in-situ scientific missions to the Jupiter atmosphere. In particular, this paper is focused on aerostatic-based mechanisms, utilizing buoyancy principles to maintain flight. Three primary aerostat types were investigated; Charliere (light-gas), Montgolfier (heated gas), and Vacuum aerostats. Supplemental systems to the aerostats were also investigated to assist with mobility control within the Jupiter atmosphere. The systems include the Balloon Guidance System (BGS) previously investigated for planetary balloons, and buoyancy controlled gliders. A Charliere would provide the most reliable lift, however one needs to ensure 13 kg of H2 for every 1 kg of payload. A Montgolfier would not require supplemental hydrogen; further analysis is needed to evaluate flight equilibrium dynamics. A BGS would provide the increased mobility otherwise unachievable with a conventional aerostat, offering steering ability (given wind gradients) between Jupiter belts and zones. Buoyancy controlled gliding is a potential solution which if executed correctly may bridge the functionality gap between traditional aerostats (with the benefits of reliable lift), and gliders (with maneuverability and navigational abilities).

Concepts for mars on-orbit robotic sample capture and transfer

A potential Mars Sample Return (MSR) mission would require robotic autonomous capture and manipulation of an Orbital Sample (OS) before returning the samples to Earth. An orbiter would capture the OS, manipulate to a preferential orientation, transition it through the steps required to break-the-chain with Mars, stowing it in a containment vessel or an Earth Entry Vehicle (EEV) and providing redundant containment to the OS (for example by closing and sealing the lid of the EEV). In this paper, we discuss the trade-space of concepts generated for both the individual aspects of capture and manipulation of the OS, as well as concepts for the end-to-end system. Notably, we discuss concepts for OS capture, manipulation of the OS to orient it to a preferred configuration, and steps for transitioning the OS between different stages of manipulation, ultimately securing it in a containment vessel or Earth Entry Vehicle.

What number of cosmic ray events do we need to measure source catalogue correlations

Recent analyses of cosmic ray arrival directions have resulted in evidence for a positive correlation with active galactic nuclei positions that has weak significance against an isotropic source distribution. In this paper, we explore the sample size needed to measure a highly statistically significant correlation to a parent source catalogue. We compare several scenarios for the directional scattering of ultra-high energy cosmic rays given our current knowledge of the galactic and intergalactic magnetic fields. We find significant correlations are possible for a sample of

A lower bound on the number of cosmic ray events required to measure source catalogue correlations

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Testbeds and technologies for potential Mars orbital sample capture and manipulation

1000 cosmic ray protons with energies above 60 EeV.

An orbiting sample capture and orientation system architecture for potential mars sample return

Recent analyses of cosmic ray arrival directions have resulted in evidence for a positive correlation with active galactic nuclei positions that has weak significance against an isotropic source distribution. In this paper, we explore the sample size needed to measure a highly statistically significant correlation to a parent source catalogue. We compare several scenarios for the directional scattering of ultra-high energy cosmic rays given our current knowledge of the galactic and intergalactic magnetic fields. We find significant correlations are possible for a sample of

A systems architecting methodology using Bloom's taxonomy to promote creative engineering synthesis

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