Piero Messidoro Enrico Gaia Maria Antonietta Perino Dario...

Global Space Exploration Conference, Washington, D.C., United States. Copyright ©2012 by the International Astronautical Federation. All rights reserved.

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SYSTEMS AND TECHNOLOGIES FOR SPACE EXPLORATION:

STEPS – AN INITIATIVE OF THE PIEDMONT REGIONAL AUTHORITY, ACCADEMY AND INDUSTRY

Piero Messidoro

Thales Alenia Space, Italy, [email protected]

Enrico Gaia

Thales Alenia Space, Italy, [email protected] Maria Antonietta Perino

Thales Alenia Space, Italy, [email protected] Dario Boggiatto

Finpiemonte, Italy, [email protected]

Beginning of 2009, Piedmont Region and Thales Alenia Space, together with Politecnico di Torino, Universita`

di Torino, Universita` del Piemonte Orientale, ALTEC and 22 SME’s based in the region, started STEPS (Sistemi e Tecnologie per l’EsPlorazione Spaziale = Systems and Technologies for the EsPloration of Space), an innovative

collaborative project for accelerating the development of advanced technologies and promoting worldwide the technological excellence of the Piedmont Aerospace District (PDA). In these years, the STEPS project involved a considerable number of scientists and engineers, young and experts, in the space exploration topic globally

recognized as strategic for the development of the humankind and for the exploitation of innovation opportunities. Thales Alenia Space Italia (TAS-I) coordinates the overall project and the single work packages and directly contributes to research and develop solutions for: Entry Descent and Landing, Surface Navigation, Surface Mobility,

Rendez-vous and Docking (RVD), Protection from planetary environment, Inflatable structures and multifunctional Smart Skin, Landing legs including shock absorbers, Thermal protection and Aerothermodynamics, Energy management and regenerative Fuel Cells, Health Management System (HMS) and composite structures modelling,

Human Machine Interfaces (HMI), Virtual Reality and Collaborative Engineering. At the end of the project in May 2012, a series of real and virtual demonstrators together with the relevant technological areas have been presented showing how these technologies contribute to the creation of complex and advanced systems for the robotic and

human space exploration missions. The obtained results in the different technological fields and in the associated systems (i.e. the Pressurized Rover and Lander), demonstrate the validity of the adopted approach and of many

technical choices made during the project. In addition the successful set-up and utilization of technological engineering areas aimed at defining a new infrastructure for Concurrent Engineering design, simulation and virtual reality, at reproducing the environmental conditions and soil typical of Moon and Mars, and at developing and

validating solutions for the different technology areas completed the fulfilment of the STEPS objectives. The gained knowledge has already allowed the preparation of several proposals for advanced studies and projects and promises interesting industrial perspectives and opportunities for the companies involved in the project. Recently a new

proposal has been presented to the Piedmont Region for a possible continuation of the project (i.e. STEPS 2). The initiative is being observed by different key players in the space sector including ESA, which appreciated the quality of the technical content as well as the potentials of the adopted innovation model based on an open and dynamic

collaboration. The paper describes the STEPS project, reports on its current results and introduces the envisaged perspectives.

I. INTRODUCTION

In the International panorama of Space programs the top powers (USA, Europe, Canada, Russia, Japan, China, India and Republic of Korea) are developing

their own autonomous initiatives but are also discussing in international forums the possibility to make synergy and harmonize their efforts on the Space Exploration

challenge.

As recently discussed during the ISECG

(International Space Exploration Coordination Group) meeting held in Kyoto on 30th August 2011, where representatives of ASI (Italy), CNES (France), CSA

(Canada), DLR (Germany), ESA (European Space Agency), JAXA (Japan), KARI (Republic of Korea), NASA (United States of America), Roscosmos (Russia)

and UKSA (United Kingdom) took part, “a long-term strategy for human space exploration shall be planned


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beginning from the International Space Station and expanding human presence in the solar system leading ultimately to human missions to explore the surface of

Mars”. The result of this debate will be a Global Exploration Strategy which according to William Gerstenmaier, outgoing ISECG chair and Associate

Administrator of the NASA Human Exploration and Operations directorate, “will facilitate the ability of

space agencies to form the partnerships that will ensure robust and sustainable human exploration."

This Global Exploration Roadmap as preliminary planned identifies two potential pathways: "Asteroid

Next" and "Moon Next." Each pathway represents a notional mission scenario over a 25 year period describing a logical sequence of advanced technology

developments, exploitation of the ISS, planetary robotic missions and human exploration missions (as reflected in the following ISEGC Global Exploration Road Map

where the above options are identified by the Agencies – see Fig. 1).

Fig. 1 – ISEGC Global Exploration Road Map

In this context, NASA plans to conduct a routine cadence of robotic missions to the Moon and NEAs

with Mars’ surface as a horizon destination for human exploration before 2040. For this purpose, NASA continues his crew vehicle (MPCV - the former Orion)

and heavy launcher (SLS) definition activities besides the developments of commercial cargo and crew

transportation programs like COTS (in which TAS-I is involved as responsible of the Cygnus/PCM), in parallel to the exploitation of the International Space Station

until 2020 in particular using it as a test-bed for Space Exploration.

In the USA in addition to the Commercial Transportation Services other private initiatives are on-

going, such as the Google Lunar X-Prize, for developing a landing/mobility mission to the Moon where also a “Team Italia” (involving TAS-I,

Politecnico di Torino, ALTEC and other PAD SME’s) is participating to the competition.

Europe and Italy are following a similar development path which will be likely confirmed in the next Ministerial Council in November 2012 on the basis

of the European scenarios presently under discussion in ESA and summarized in the following road maps where again the two alternatives “Moon Next” and “Asteroid

Next” are shown (see Fig.’s 2 and 3). In this context TAS-I is leading one of the two studies with the

objective to support ESA in this definition effort.

Fig. 2 – ESA “Moon Next” scenario

Fig. 3 – ESA “Asteroid Next” scenario

In parallel and consistently with these scenarios, ESA is already collaborating with USA and other

international partners on space exploration projects.

In fact in the framework of the Aurora programme ESA is developing in cooperation with Roscosmos the ExoMars mission to bring on Mars a lander and a rover

(launches foreseen for 2016 and 2018) for investigating the Martian environment in preparation of future human missions. TAS-I is prime contractor of ExoMars and


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ALTEC is responsible for the ground control of the rover. New technologies are also under development and will be demonstrated in the Aurora programme to

prepare the international Mars Sample Return mission which will carry back on Earth some samples of Mars terrain.

On a shorter term view, ESA is also considering to

extend the activities on ISS at least until 2020 implementing derivatives of ATV (Automated Transfer

Vehicle, for which TAS-I is responsible of the pressurized Cargo Carrier) and exploiting the station as a technological test-bed. This has recently brought to a

Call for Ideas to which TAS-I contributed involving PAD partners. ESA is also studying a mission to the Moon (Lunar Lander) and is developing new

transportation systems demonstrators such as re-entry vehicles (e.g. Expert and IXV for which TAS-I is prime contractor). Decisions on these matters in terms of

follow-on are expected in the next ESA Ministerial Conference.

In general, the short term development approach

adopted by international institutions is focused on the main critical “enabling capabilities” in order to assess the technology needs over a longer span of time with the

inherent benefit of not stranding technologies for a single destination. This Capability-Driven Framework, as addressed by NASA, ESA and the other Agency’s, is

the most viable approach given the cost, technical and political constraints and provides a foundation for the Agency’s needed technology investments.

STEPS has been conceived in line with the above

described stream of initiatives with the aim to catalyze the technology development competencies available in

the PAD to be ready to accomplish those enabling capability needs identified by the international institutions.

II. THE STEPS PROJECT

Synergies between the Comitato Distretto

Aerospaziale del Piemonte, primary coordination body between local institutions and aerospace industry, research and academy, and the European Regional

Development Fund (ERDF) 2007-2013 have enabled Regione Piemonte to design and fund the initiative

“Piattaforma Aerospazio” for accelerating the innovation of aerospace technology within the Region and reassuring its worldwide excellence.

In fact Regione Piemonte assumes regional

competitiveness and employment through research and

innovation as key objectives of the ERDF exploitation,

and Aerospace as priority in its three-year Research

Plan. The “Piattaforma Aerospazio” commands the

concentration and integration of resources on three

comprehensive projects of high relevance and competitive edge potential for the local aerospace technology network (see Fig. 4):

• UAV based System for civil Land Monitoring (SMAT F1)

• Green Engine for Air Traffic 2020 (GREAT

2020)

• Systems & Technologies for Space ExPloration (STEPS)

Fig. 4 – Regione Piemonte Aerospace Platform The innovation policy model of European

Technology Platforms, in addition to ERDF, are the assumed references for the implementation schemes of the “Piattaforma”, in synergy with regional laws for the

development of research, innovation and production. Specifically for Space, primary topic of interest fo r

the development strategies of associated technologies in Regione Piemonte is Space Exploration; other major topics of interest are represented by management of

Space Science data and Space Operations, Space

Transportation and Technology spin-off.

In this context STEPS represents a joint development of technologies and systems for Space Exploration by a

consortium led by Thales Alenia Space and including Politecnico di Torino, Università di Torino, Università del Piemonte Orientale, ALTEC and 22 SMEs based in

the region. It started in January 2009 and concluded in May 2012.

The budget of almost 10 M€ allocated to this project by

Regione Piemonte, plus an amount of about 8 M€ engaged directly by the involved Industry and Research Centres, have enabled novel engineering and

experimentation work in several key directions for leading edge Space Exploration, and allowed to involve a considerable number of students and young graduates

in developing highly sophisticated technical skills.

The contents of the project are also trimmed in a way to be closely synergetic, and not duplicating or diverging, with the state-of-the-art national and international

initiatives in space Exploration, namely those of the leading space Agencies. In particular, the progress of

S ystem Primes, SMEs, Academies

and Research Centers

Global market

opportunities

UAV Systems for civil land

monitoring (SMAT F1)

Mac

ro-p

roje

cts

Systems & technologies

for Space Exploration (STEPS)

Green Aeronautical Engine

technologies (GREAT 2020)

European Regional

Development Funds


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the project is regularly shared with executives of the European Space Agency.

TAS-I coordinates the overall project and the single work packages and directly contributes to research and

develop solutions for: Entry Descent and Landing, Surface Navigation, Surface Mobility, Rendez-vous and Docking (RVD), Protection from planetary

environment, Inflatable structures and multifunctional Smart Skin, Landing legs including shock absorbers,

Thermal protection and Aerothermodynamics, Energy management and regenerative Fuel Cells, Health Management System (HMS) and composite structures

modelling, Human Machine Interfaces (HMI), Virtual Reality and Collaborative Engineering. The different technologies are finalized towards application on two

important elements of Space Exploration scenarios namely a lander and a pressurized rover which are applicable to both robotic and human exploration needs

and for Moon and Mars missions. The fig. 5 shows this conceptual approach that links the different technologies

to the main applicable systems.

Fig. 5 – STEPS conceptual approach

The STEPS project was oriented to investigate the specific technologies as well as to develop virtual and

physical demostrators of lander and rover together with a series of engineering infrastructures and technological areas.

III. STEPS RESULTS

The STEPS objectives and expected results have been introduced in previous publications

1, the final

achievements are summarized in this section according to the main technology areas.

III.I Entry, Descent, Landing and Surface Navigation Contrary to past missions characterized by large

landing dispersion ellipses, future Mars missions will be

targeted at very specific sites maybe also located in rough and hazardous areas due to scientific interest. Spacecrafts will then be required to autonomously

perform the critical landing operations, including the

identification of the best landing site within the selected landing area and the avoidance of surface obstacles.

The STEPS project plans the investigation of the

Machine Vision field to enhance the image acquisition and processing techniques and permit their fruitful utilization in future space missions.

The activities focused in enhancing the techniques inherent to both the Image Processing area (i.e.

Filtering, Enhancement, Restoration, and Compression) and the Computer Vision area (i.e. object recognition) and SLAM (Simultaneously Localization and Motion)

algorithms development) A considerable effort has been given also on the

integration of both the Machine Learning and the

Computational Intelligence approaches with the Machine Vision system in order to solve the issues identified in previous studies performed by TAS-I on:

• Entry, Descent & Landing (EDL) approaches guided by means of a camera aimed to direct a lander to the chosen landing point

• Rover Surface Autonomous Navigation realized via a stereo vision system and correlated algorithms (i.e.

path planning algorithms) aimed to autonomously guide a rover in an unknown terrain

EDL activities

The performed activity resulted in the developed o f a vision-based GNC for EDL that will operate during

the powered descent phase of the landing and cover the complete GNC chain. In particular: �� image processing algorithms for hazard mapping

and recognition of the position with respect to the nominal landing site

�� piloting function for the selection of the best

landing site keeping into account precision and safety requirements

�� adaptive guidance by generation of the best reference trajectory to reach the landing site selected by the piloting function

�� vision-based navigation by fusion of information about the state of the lander from image processing and other sensors

�� control algorithms The integration of the developed algorithms with

the detailed simulation of sensors, actuators and

Martian environment resulted in a simulation too l (STEPSIm) allowing analysis and virtualization of the

GNC technology. Good results have been obtained testing the system using both real and synthetic images (created by means of Pangu software).

The trajectory visualization is shown in Fig. 6 together with an example of the elaborated coloured hazard mapping of the Mars site Promethei Terra ;

Fig. 7 shows the visual navigation GNC validation facility and associated drone developed in TAS-I for STEPS.

Fault Diagnostics Infrastructures

Vision and Terrain

Reconnaissance

Navigation and Guidance

Man-machine Interfaces

Environmental Control

Pressurized

Structures

Rigid and Inflatable

Structures Energy Management

Landing/Ascent Vehicles

Virtual Reality Concurrent/Collaborative

Design

Multidisciplinary Optimization

Aerothermodynamics

Locomotion and Mechanisms


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Fig: 6: Examples of EDL trajectory and landing site hazard mapping

Fig.7: TAS-I GNC Validation Facility and drone

Rover Autonomous Navigation

The Rover Autonomous Navigation development was performed starting from the results obtained in

the EDL framework adapting the GNC algorithms to permit the identification of the camera position with respect to a planar pattern and the subsequent

application on a surface mobility vehicle. The resulted navigation logic flow is shown in Fig. 8 and

the rover demonstrator used for its functional verification in Fig. 9.

Fig. 8: Rover Navigation Logic Flow

Fig. 9: Rover Functional Demonstrator

III.II Surface Mobility, RVD and Protection from Planetary Environment

Future exploration missions are characterized by

complex systems architectures and related assembly needs, requiring the performance of RVD operations

among different spacecrafts both on-orbit and on-surface. Moreover, the need to operate in adverse environments for long time requires the development of

new materials and technologies to both sustain the harsh conditions and protect the systems from the tough effects of the local environment. Within the STEPS

project, three different research fields have been deeply investigated to solve some of the issues identified in previous studies:

• Surface Mobility: development of an electric motor-wheel to be utilized on a Lunar Pressurized Rover, capable to sustain the lunar peculiar rugged terrain

and assuring enhanced performances (i.e. in terms of exploration range and velocity) and a good level of

reliability

• Environment Protection Solutions: development of both a dust removal and an enhanced radiation

protection systems to protect both astronauts and equipment’s from the lunar environment during a surface exploration campaign

• Rendez-Vous & Docking: Development of both a Rendezvous & Docking mechanism and a 2D test facility for validating on ground the whole

technology.

Surface Mobility

In designing the direct-drive motor that was selected in place of traditional geared solutions for reducing

moment of inertia and improving efficiency, reliability and easiness to install, particular care was taken to account lunar peculiar thermal excursion and dust

effects. In parallel with the motor, also a 1 m diameter steel-made wheel was developed. The wheel has been designed to sustain the rover weight, transmit traction,


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minimize the sinkage and resist to the required cycling. A great effort was put in finding a suitable thermal control system guaranteeing that all motor components

remain among allowable limits. The realized motor/wheel is shown in Fig. 10.

Fig. 10: STEPS Motor and Wheel

Environment Protection Solutions To test the dust effects on the motor/wheel system, a

new Planetary Environment Simulation Chamber

(PESCha) was developed using traditional (Mars) and improved (Moon) dust simulants (see Fig. 11). The most promising dust removal system identified after the tests

was realized together with an enhanced radiation protection system (see Fig. 12).

Fig. 11: PESCha and dust simulants

Fig. 12: Dust Removal and Enhanced Radiation

Protection Systems RVD

A different research developed both the docking mechanism mounted on the target and chaser vehicles and the engineering technological area for testing the

mechanism (see Fig. 13). The realization of this RVD test facility permitted the validation of the GNC algorithms too.

Fig. 13: RVD Facility with Chaser, Target and docking Mechanisms

III.III Inflatable Structures and Multifunctional Smart Skin

The future space exploration scenarios foresee a

progressively adoption of new materials, inflatable systems and smart solutions to be implemented for the new spacecrafts’ design, inspiring technological

challenges for structural and thermal engineer. Two different fields have been investigated as described

herein.

Inflatable structures

The inflatable structures technology can provide great benefit for the on-orbit phases of manned mission combining lightness, strength and reduced volumes at

launch but it requires in depth investigations to guarantee levels of structural performance comparable with present metal structures and to fulfil the identified

deployment function constrains. The analyzed flexible wall is obtained using a multi-layered configuration to guarantee thermal insulation, Micro Meteoroids &

Orbital Debris (MMOD) protection, cosmic radiation shielding, structural pressure containment and adequate

resistance against crew accidentally induced aggression. The STEPS activity focused in enhancing the air containment bladder, the internal protective barrier and

the MMOD layer elements. In particular, small size wires to be embedded in the fabric used to produce the inflatable layers and new nano-charged and metalized

polymeric materials have been studied and developed for both the internal barrier and the bladder. The Fig. 14 shows the internal barrier where its passive

function is enhanced embedding different type of wires (e.g. thin cupper wires, optical fibers) in order to carry

small amount of power or transmit signals. Moreover the cables might also serves themselves as sensors: their capacitance or impedance could be used

to monitor different environmental conditions such as temperature, humidity, stress, etc. Embedded wires may also play an important role in

limiting adhesion of (lunar/mars) dust by dispersing electrostatic charges or applying active electromagnetic fields in a surface habitat or airlock.


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The conductive fabric functionality have been tested and verified for what concern power transmission and signal attenuation (see again Fig. 14).

Fig. 14: Inflatable Structure internal Barrier with

embedded wires and its functional tests The Fig. 15 shows an enhanced air containment

bladder (Polyurethane improves sealing with metals wrto the classic Polyethylene) with respectively grapheme nano-particles and Aluminium co-extrusion,

both solutions to minimize air permeability and improve the inflatable structure behaviour against perforation or wrinkles.

Fig. 15: Nano-charged and metalized air

containment layer

In parallel, investigations on an inflatable manned system were conducted to develop an inflatable airlock for the pressurized rover to be used on the

planned surface (see its concept in Fig. 16).

Fig. 16: STEPS Inflatable Airlock for Surface

Smart & Multifunction Structures

Besides inflatable structures, the multi-function

capability was extended in rigid structures including functions as avionics, thermal control and health monitoring. In particular, two different technological

solutions were addressed in the Smart Multifunctional Structures field: �� the thermo-mechanical substrate

�� the functional layer with circuitry and electronics (the so called Smart Skin)

The performed activity allowed executing analysis

and trade-off on possible substrate materials, design and manufacturing a smart skin and completing a

multidisciplinary optimization loop on the developed elements. Fig. 17 shows the Smart Skin solutions and the new Thermal Control area where technology

functional tests were carried-out.

Fig. 17: Smart Skins and Thermal Control Area

III.IV Landing Legs including shock absorber In the context of the soft landing capabilities fo r

Space Exploration, the STEPS project planned to focus the effort towards the improvement of some

technological aspects related to Landing Legs and Active Shock Absorbers (ASA) technologies.

The driving requirements for any Landing Leg

design are to ensure: safe landing, limited accelerations at touch down and topping avoidance.

Landing Legs The R&D aims to improve the basic landing gear

performance, adding new characteristics and capability, like: lander mobility, levelling, walking, terrain

adaptability. At the end of a Landing Leg concepts design trade-off, the tripod configuration has been selected, due to its superior efficiency compared to the

other studied solutions. Fig. 18 shows the landing leg concept and its realization.

Fig. 18: Landing Leg concept and realization

Active Shock Absorber (ASA) The research is focused on improving the landing

capability on unprepared terrain by substituting passive dampers with active shock absorbers that could lead to an efficiency increasing ,i.e. landing gear reutilization,


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hopping mobility exploitation, reduction of terrain roughness induced vibrations, motion energy reduction, energy recovery/harvesting.

Among different possible active shock absorbers technologies, electromagnetic actuators have been selected for the relatively easy control architecture and

for the absence of freezable fluid inside the mechanisms. A reference scenario has been identified to

determine the driving performance and requirement for ASA that corresponds to the Moon South Pole where the surface if very rough. The location selection

has derived other two important requirements: the lander shall be able to overtake 0.5 m obstacle and shall be able to land on an inclined terrain with 15 deg slope,

with a total lander body mass of 800 kg (see Fig. 19). ASA is capable to work in a bidirectional way i.e.

during landing ASA act as a damper, after landing ASA

may adjust the lander inclination. Another possible application of this technology is

the ASA adaptation to fit inside a rover suspension system; in this case, ASA is used to recover energy from the rover movements and to reduce terrain

roughness induced vibrations. Fig. 19 shows also the ASA and the relevant test set-up.

Fig 19: Lander Legs performance, ASA and its test

III.V Thermal protection and Aerothermodynamics

The most suitable protection from the high temperatures involved for both Mars entry modules and Earth re-entry capsules is represented by ablative shields.

Ablative materials are in fact characterized by a higher reliability than non-ablative protections (i.e., ceramics)

and simpler process of manufacturing and assembly, hence leading to more contained costs. Furthermore, ablative materials have a broader scale of applications,

being potentially used in those zones (i.e., nose, stagnation points) exposed to high flux levels exceeding temperature limits of ceramic protections.

The STEPS research aimed basically to select at least two compositions of material candidate for ablative thermal protection systems of Mars entry modules and

the simulation of the ablative material behaviour by the implementation of both a dedicated tool and an integrated code able to simulate the interaction between

the external thermo-fluid dynamic and the ablative behaviour, in terms of ablation, thermal conduction, and surface recession, as well as to provide the capability to

implement optimization strategies relative to the shield shape. Final materials have been selected by an experimental-

analytical simulation approach, in particular the more promising compositions are: Epoxy matrix with filler,

PFA charged with Graphite and Silicates. Stand-alone ablation tool, AblationFOAM has successfully been validated by a cross-checking

between experimental data (Apollo IV mission case) and commercial software (SAMCEF/Amaryllis) results. The integrated ablation code and the integrated shape

optimization technique and algorithms guarantee a stronger thermal-ablation-fluid-dynamic coupling, therefore a more reliable design.

Fig. 20 shows one of the ablative samples and a typical code result.

Fig. 20: Ablative TPS and an AblationFOAM result

III.VI Energy Management and regenerative Fuel Cells

Energy management (production, storage,

distribution and utilization) is a key enabling technology of any exploration mission scenario.

The STEPS research in this field has been based on

regenerative fuel cells for space exploration systems (e.g. planetary base, rovers).

Different solutions were investigated depending on

the specific mission requirements and a preliminary architecture assessment has been performed depending on the energy production and resources regeneration

balance. Regeneration would permit a more efficient management of water and gasses, key factor to make

long duration human missions feasible. The research activities focused on the definition of a

proper energy management system including a PEM

fuel cell and an electrolyser for regenerating oxygen and hydrogen, a water management methodology, and a thermal control system.

A demonstration and test technological area has been realized to prove the capability of achieving a RFCS with a complete closed loop.


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Fig. 21 shows the breadboard of the Fuel Cells and of the Electrolyser.

Fig. 21: Fuel Cells and Electrolyser Breadboard

This research was linked with the activity of the TAS-I Recycle Lab in particular for two aspects: selection of

possible materials to be used in the storage of the water that will be produced by the fuel cell prototype and evaluation of their suitability through regular analysis of

the main physical-chemical water parameters. Two inflatable, commercial and inert containers were

compared and a new breadboard based on Electro Dialysis Reversal (EDR) was realized (see Fig. 22).

Fig. 22: Fuel Cells water storage containers and EDR

III.VI HMS and composite structures modelling

The increasing use of composite materials in space

industry highlights the need to better foresee their

behaviour and to monitor their state during operative life. The objective of STEPS was to perform a critical composites fracture mechanics analysis and a detailed

evaluation of the best technologies suitable for analyzing and monitoring the composite structures. Different fracture mechanisms take part in composites

material and different methodologies shall be implemented to understand how the composites failure modes start, evolve and interact each other up to the

global failure of the structures. After having characterized the fracture mechanisms in composites

materials, different software have been assessed trying to obtain a correct critical composites fracture mechanics. So, a new methodology for analysing

fracture mechanics on multi-layer structures has been developed and specific tests for its validation has been performed leading to promising results. This confirms

also the selected Health Management System solution

utilized to monitor the thermo-structures status. Fig. 23 shows the HMS logic and STEPS tested solution.

Fig. 23: HMS logic and implemented solution

III.VII Human-machine interface

The presence of humans in future Exploration missions will increase the possibility of discovering or

solving unexpected situations related to the operability or autonomy of spacecrafts/robots.

The objective of STEPS in the field of command and

control systems focused on the development of an immersive and integrated Human Machine Interface (HMI) permitting both remote control of a un-

pressurized lunar rover equipped with a robotic arm and the next direct collaboration among human and robot in the same environment (Crew Collaborative Robotics).

The specific target functions and technologies are:

• Ground station for the control of a unmanned vehicle on IVA, 1G, time delay conditions;

• Vehicle control during Extra vehicular close to or on-board the rover;

• Specific interfaces for human-machine communication (including Augmented Reality - AR)

• Artificial-intelligence architecture for the vehicle allowing sliding autonomy levels depending on the

operation/collaboration needs and prediction capabilities.

The development of the intended immersive HMI is based on a Human Centred Design approach based on ISO 13407 standard and is closely connected with the

virtual reality researches since users behaviour during operations could easily be tested and tracked on simulated environment by applying virtual models of

the systems. Main results include:

• Realization of artificial intelligence subsystems necessary for a Human machine interface use case

characterized by the intervention of a rover with a robot arm and sliding autonomy assisting an astronaut

in trouble during an EVA mission;


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• 3D Graphical User Interface over imposed on the real world (AR) providing support to the human operator during the execution of procedural tasks;

• Development of the ubiquitous arm: wearable system for control of the robotic arm end effectors

Fig. 24 shows the HMI command and control, logic

results.

Fig. 24 HMI Command and Control logic

III.VIII Virtual Reality and Collaborative Engineering

A peculiar characteristic of space product (in

particular for Space Exploration) is the presence of a high number of disciplines and function developing and operating a system requiring considerable optimization

and robustness characteristics. This is typically tackled by carrying a number of development cycles for ensuring a consistent and complete evolution of the

system but requires long time and work often constrained by the capability of sharing information efficiently and effectively.

Among the main objectives of STEPS there is the development of a Centre for the Collaborative

Engineering and Virtual Prototyping of complex space systems permitting the synergy of all stakeholders along each phase of the product development.

This activity aims at defining, prototyping and validating an infrastructure and related process, able to support design activities during all project phases (0-A

with Concurrent Design Facility, and B-C/D with the framework currently under development), allowing

• Improvement of Online/Offline Collaboration among

all stakeholders

• Model Based System Engineering: more models, less documents to efficiently and consistently synthesise

information

• Definition of a common baseline, machine-interpretable which can be integrated in different

analysis tools

• Saving time for searching data and giving more time for engineering activities

• Early and cheaper visualization of a virtual mock-up permitting multidisciplinary simulations.

The study resulted in the definition of a structured database and web editor based on a valid meta-model for sharing data of system engineering and disciplines

analysis. Several tools were realized for the realization of

complete and realistic virtual scenarios replicating

physics of planetary environment and of the systems under development (Pressurized lunar rover, Mars Entry

vehicle, landing vehicle). The Virtual Reality laboratory is fully operative and

already provides support to the development of systems

and the verification of operations by users. The Fig. 25 shows the Concurrent Engineering (CE)

environment and some Virtual Reality (VR) laboratory

features.

Fig. 25: CE Environment and VR Lab features

III.IX Pressurized Rover and Lander Demonstrators

The STEPS Technology Systems Demonstrators has

been developed in order to highlight the selected system applications, namely: a Pressurized Rover for Human planetary mission and an autonomous planetary lander.

The Pressurized Rover Flight Model will be sized for a nominal crew of 4, it would have a nominal speed of 15 km/h and capable of negotiating slopes up to 30 degrees

and obstacles up to 0.5 m. The mass of a pressurized rover for lunar exploration should be around 8000 kg and the overall dimensions would be 5m x 4m x 3.8m.

The overall sizing of the STEPS Pressurized Rover Demonstrator is about 1:2 of the flight unit and the mass

is nearly 1500 Kg. The locomotion system is sized to reproduce as much as possible terra-mechanics conditions representative of reduced gravity. The

maximum speed has been limited to 5 km/h for safety reasons. The locomotion platform includes six elastic wheels and motors accommodated in the wheels hubs.

CATIA Model

A PI P roper ties

file

CATIA T ree

To EPS

Mapping

W eb E ditor

System Model

3D Models (V RMLs) V E R

I T A

S A

d.

User

Modelica model

CAD model

Master DB

Consistency

Checker

Online Collaboration

Virtual

env ironment


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An inflatable airlock demonstrator is located in the rear part to represent the capability of the Pressurized Rovers of docking or undocking to/from planetary habitat

elements. The main scope of the rover demonstrator developed in STEPS is to collect, integrate and test in a system platform the technologies coming from other

STEPS work packages i.e. direct drive motors, active shock absorbers, technological upright, vision system

for digital elevation map, inflatable airlock, elastic wheels, remote control station and related MMI.

In addition, the pressurized rover demonstrator

includes others technological Commercial Off-The-Shelf (COTS) items to be evaluated like the high energy density battery pack, Laser scanner for the collision

avoidance system, front and rear navigation cameras, foldable solar panel, commercial off-road shock absorbers, motor electronic drivers, inertial

measurement unit, on board main controller and vision computer. The different STEPS technologies and the

complementary COTS are summarized in Fig. 26.

Fig. 26: Pressurized Rover demonstrator technologies and COTS

In particular, the demonstration and testing phas e allow investigating the following: locomotion system behavior on a rocky surface similar to moon/mars soil,

two different steering systems, elastic wheel behavior, utilization of a rotary case motor, vision system in support to manual navigation, inflatable airlock

technologies, active shock absorber application, different types of MMI for rover control, make experience with Lithium Polymer battery, optimization

of the energy budget.

Similar Approach has been adopted for the lander physical demonstrator to be seen in conjunction with the GNC aspects covered in section III.I above.

The Fig. 27 shows the two demonstrations on the Moon-Mars terrain Simulator (MMTS) built in ALTEC for the STEPS project.

Fig. 27: Rover and Lander Demonstrators on the MMTS

IV. CONCLUSIONS AND PERSPECTIVES

Regione Piemonte, in the frame of its initiatives to

sustain innovation and promote the development strategy of the PAD, supported the STEPS Project, an

important research program focused on the horizon of the space exploration. In this three-year initiative TAS-I leaded a versatile group of partners including ALTEC,

Politecnico di Torino, Università di Torino, Università del Piemonte Orientale and 22 local SMEs. The project developed a series of Space Exploration enabling

technologies and several technological demonstrators (both virtual and physical) finalized to lander and Rover systems applicable to both robotic and human missions.

Moreover, it included the development and utilisation of technology validation areas and of CE

environments, simulation and VR facility. These activities and infrastructures are promoting the PAD network as a centre of excellence for the space

exploration. STEPS is contributing to the employment growth in high tech sectors and also training and recruitment of young people both in the industrial and in

the research systems. This collaborative work in innovative research will

likely continue in the next future considering the

excellent results obtained in this first phase. In fact the proposal for a STEPS 2 project has been presented to

the Regione Piemonte and is presently under evaluation. The basic idea is to continue the technology development on a subset of the STEPS technologies,

selected on the basis of the quality of the first phase results and also of the opportunity to face a validation in space in short-medium term in some of the Space

Exploration initiatives that are planned at national and international levels.

V. REFERENCES Ref. 1: M.A. Perino, P.Messidoro, E.Gaia, D.Boggiatto

“STEPS Project – Technologies and Systems for Space Exploration”, IAC-11.D3.2.2 – IAF Cape Town 2012


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