Chassis & Locomotion Breadboard Phase B1

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Nov 14, 2013 (4 years and 1 month ago)

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Proposal No. HR007.01.26/Tech

Reference

HR007.01.26/Tech
.

Revision

-

Date

2007
-
02
-
15

Reg. No.


Page

1

of
28





ExoMars Rover


Chassis & Locomotion Breadboard Phase B1



Task

: 5.1 Engineering





PART 1


TECHNICAL PROPOSAL





HR007.01.26/Tech

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2

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28




Table of contents

1

Introduction
................................
................................
................................
...............................

3

2

Objectives

................................
................................
................................
................................
.

4

3

Applicable Documents

................................
................................
................................
.............

4

4

Reference Documents

................................
................................
................................
..............

4

5

Technical Proposal (
Baseline)

................................
................................
................................
.

6

5.1

Chassis and Locomotion Design

................................
................................
..............................

6

5.1.1

Assessment of the Rover locomotion requirements

................................
..............................

6

5.1.2

Assessment and trade
-
off of alternative C&L concepts

................................
.........................

7

5.1.3

Adaptation and validation of analytical locomotion performance evaluation tools

..................

8

5.1.4

C&L subsystem definition and design optimization

................................
...............................

8

5.1.5

Detailed locomotion pe
rformance prediction and evaluation

................................
.................

9

5.1.6

Assessment of Electrical, Thermal, TM/TC and structure requirements of the C&L subsystem

9

5.1.7

Generation of reduced mechanical FEMs and thermal TMM/GMM
s

................................
.....

9

5.1.8

Consolidation of the C&L Subsystem Requirement Specification

................................
..........

9

5.1.9

Identification and analysis of critical technologies for the C&L subsystem
.............................

9

5.1.10

Prepar
ation of Programmatics for phase B2CD activitities

................................
..................

9

5.1.11

Other remarks on C&L Design

................................
................................
...........................
10

5.2

Chassis and Locomotion Breadboarding

................................
................................
................
11

5.2.1

Breadboarding tasks

................................
................................
................................
............
11

5.2.2

Locomotion Breadboard

................................
................................
................................
.......
12

5.2.3

Other remarks on C&L Breadboarding

................................
................................
.................
20

5.3

Assembly, Integration and Verification

................................
................................
....................
22

5.3.1

• Model philosophy

................................
................................
................................
...............
22

5.3.2

• Verification methods

................................
................................
................................
..........
22

5.3.3

• Requirements traceability approach
................................
................................
...................
22

5.3.4

• Preliminary AIT flow

................................
................................
................................
...........
23

5.3.5

Other remarks on C&L

Assembly, Integration and Verification

................................
.............
24

5.4

Mathematical Simulation and tools

................................
................................
.........................
24

6

Improvement and Optimisation

................................
................................
..............................
25

7

Attachments

................................
................................
................................
.............................
26

7.1

A
ttachment 1
-

ISO 9001:2000 HEIG
-
VD
-
CeTT Certificate, issued by IQnet

...........................
26

7.2

Selection of relevant publications

................................
................................
............................
27


Table of Illustrations

FIGURE 5.1
-
1:
RCL TYPE E, WITH WAL
KING
CAPABILITY, FROM RDE
-
4. IN THE CURRENT PR
OPOSAL THE
RCL
-
E IS THE BASIC CHOIC
E, BUT NOT WITH THE
DISPLAYED WALKING CA
PABILITIES HOWEVER.

................................
................................
................................
................................
................................
.......................

8


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FIGURE 5.1
-
2: EXOMARS ROVER CHA
SSIS & LOCOMOTION SY
STEM AND SUBSYSTEMS

..............................

8

FIGURE 5.2
-
1: OVERVIEW OF PRODU
CT TREE

................................
................................
................................
..........

13

FIGURE 5.2
-
2

: SKETCHES OF LUGGED

WHEELS WITH CHEVRON
-
SHAPED OR MIXED TRAN
SVERSE
AND LONGITUDINAL GRO
USERS.

................................
................................
................................
.....................

14

FIGURE 5.2
-
3: IMU FOR ROBOTIC P
L
ATFORM, INCL.
INVENSENSE IDG
-
300 [FROM RDE
-
17]

........................

14

FIGURE 5.2
-
4:
UML CLASS DIAGRAM OF

THE INTERFACES WITH
THE MOTION EXECUTION

SUBSYSTEM

( FROM [ADE
-
2] FIG. 3.7
-
1.)

................................
................................
................................
................................
....

16

FIGURE 5.2
-
5:
TYPICAL HUMAN
-
MAC
HINE INTERFACE FOR I
NTERACTIVE SPECIFICA
TION OF RELATIVE
RECTILINEAR, CIRCULA
R OR POINT MOTIONS
( FROM [RDE
-
18] )
................................
.............................

17

FIGURE 5.2
-
6:
TYPICAL INTERTASK ME
SSAGE EXCHANGE DIAGR
AM IN BASIC OPERATIO
N
(RE. P.31
FROM [ADE
-
2] )

................................
................................
................................
................................
........................

17

FIGURE 5.2
-
7:
PRINCIPLE FOR TRAJEC
TORY TRACKING (LEFT)

AND MULTIPLE WHEEL C
OORDINATION

(RIGHT) ( E.G. [RDE
-
10] , [RDE
-
12])

................................
................................
................................
......................

18

FIGURE 5.2
-
8:
PRINCIPLE OF THE MET
HOD OF AMIGUET FOR A
BSOLUTE INTERPOLATIV
E M
OTION

......

19

FIGURE 5.2
-
9:
CONTROL HIERARCHY FO
R LOCOMOTION, INCLUD
ING MANAGEMENT OF MU
LTIPLE
WHEEL TRACKING AND S
TEERING MOTORS

................................
................................
................................
..

19

FIGURE 5.2
-
10: GAISLER GRESB SP
ACEWIRE ETHERNET BRI
DGE

................................
................................
......

21


1

Introduction

This
technical proposal

describes the tasks that the HEIG
-
VD shall be responsible of in the frame of
the ExoMars Phase B1 for the Rover Vehicle Chassis and Locomotion Subsystem Design,
incorporating the Design and Manufact
ure of the Chassis and Locomotion Breadboard, for what
concerns «

Engineering

» (re. RDE
-
1).

Astrium Ltd is the Rover Vehicle System Lead, responsible to Alcatel Alenia Space Italia (AAS
-
I),
who is the Prime Contractor for ExoMars phase B1, under contract

from the European Space
Agency (ESA).

RUAG
Aerospace
is bidding to be the Prime Contractor for the Chassis and Locomotion (C&L)
Subsystem Design, responsible to Astrium Ltd.

HEIG
-
VD (E
-
Contractor) is responsible for the Engineering task in the Chassis

and Locomotion
(C&L) Subsystem and shall therefore report to RUAG.

The Chassis & Locomotion Subsystem is a part of the ExoMars Rover, and its breadboard will be
particularly useful not only to prepare next phases of same subsystem but also to help testi
ng other
components, in particular the navigation subsystem.

HEIG
-
VD
has studied the basic documentation for Chassis & Locomotion Subsystem.

The Engineering Task

would be managed by HEIG
-
VD.

HEIG
-
VD expects to receive the official technical documentation
after contract signature. If required,
adjustments will be done on this basis.

HEIG
-
VD
will buy all parts from s
upplier
s
. The re
quirements for
these parts would

be the same as if
they were

fabricated in
-
house.

Design of C&L breadboard as well as maths and

simulation tools will be done in the facility in
Yverdon
-
les
-
Bains (HEIG
-
VD
-
CeTT). Breadboard production, assembly, integration and verification
will be
done in a complementary way, in part in Yverdon and in part at RUAG facility in Emmen.

The project tea
m will work according to the certified CeTT in
-
house design criteria’s.


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2

Objectives

In order to achieve the program objectives in line with RUAG Aerospace (Customer) expectations
and requirements within the given budget constraints and with respect to tech
nical compliance,
planning and costs, HEIG
-
VD has established a solid project structure already in the proposal phase
that will be enhanced and confirmed as soon as the project kick
-
off has been held.

This approach guarantees that experience and know
-
how a
ccumulated during the proposal phase
will be available for the design, development and production phase, thus enabling project
management continuity of and a reasonable cost
-
performance ratio in the execution of the prevailing
subcontract program and in me
eting the challenging technical requirements.

With a long experience in conducting challenging multi
-
national projects to success and satisfaction
of our customers and partners, we have selected a highly qualified and motivated project manager in
the perso
n of Prof. Jean
-
Daniel Dessimoz as Head of the Laboratory for Robotics and Automation of
HEIG
-
VD, who has the appropriate authority of decision within our organization so that the C&L BB
Engineering Contract will be treated with due priority as required in

order to reach the ambitious
goals set by our customer.

The designated Project Manager will be seconded by Professor Philippe Bonhôte,
Head of the
Institute for Mechanical Design, Materials and Packaging Technology.
at HEIG
-
VD, who assumes
overall technic
al responsibility for the prevailing subcontract program and in achieving any and all of
the technical objectives.

Regular reporting are normal routine activities at HEIG
-
VD and will be one element helping to keep
the project on track. Any deviation from t
he nominal planning can thus be identified early and
appropriate corrective actions can be taken in a way that will minimize or, as an objective, will lead to
no impact in the project.


3

Applicable Documents

ADE
-
1

Statement of Work


EXM.RM.SOW.ASU.0001

ADE
-
2

Requirements

EXM.RM.RQM.ASU.0001

4

Reference Documents


RDE
-
1

Vol 2 Management and Financial Aspects

Vol 2 Management
and Financial
Aspects.doc

RDE
-
2

ExoMars Project Status,
G. Gianfiglio

Astra06
-
Proc.1.1.02, 2006

RDE
-
3

The ExoMars rover and Pasteur pa
yload

Phase A

study: an approach to experimental astrobiology,
The
Rover Team: Dave Barnes et al.,
International Journal of
Astrobiology (3):221
-
241, 2006


ExoMarsRoverPhaseAIn
tJournAstr006.09.20AE0
01324934.pdf

RDE
-
4

M. Van Winnendael et al., «

Developmen
t of the ESA ExoMars
Rover

»,
Proc. of 'The 8th International Symposium on Artifical
Intelligence, Robotics and Automation in Space
-

iSAIRAS’,
ㅟwi湮敮摡敬弲愮灤a


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Munich, Germany. 5
-
8 September 2005, (ESA SP
-
603, August
2005)

RDE
-
5

W. Kutcherenko et al.
«

Chassis concepts for the ExoMars Rover,
Proc. Astra 2004, ESTEC, NLNov. 2
-
4, 2004

astra2004_D
-
05.pdf

RDE
-
6

Nicolas Uebelhart« Modelling and animation of virtual
autonomous mobile robots, in physically simulated world, for the
evaluation of locomotion an
d navigation structures »,
Symposium A5.2. Human and Robotic Partnerships to Realize
Space Exploration Goals, International Space Congress IAF
(Fédération internationale d'astronautique), Fukuoka, Japan,
Oct. 17
-
21, 2005



RDE
-
7

Jean
-
Daniel Dessimoz et al
., "Ontology for Cognitics, Closed
-
Loop Agility Constraint , and Case Study in Embedded
Autonomous Systems


a Mobile Robot with Industrial
-
Grade
Components", Proc. Conf. INDIN '06 on Industrial Informatics,
IEEE, Singapore, Aug.14
-
17, 2006, pp6


RDE
-
8

Ni
colas Uebelhart, Stéphane Michaud and Olivier Michel,
"Modelling and animation of virtual autonomous mobile robots,
in physically simulated world, for the evaluation of locomotion
and navigation structures", « DARH
-
2005
-

1st International
Conference on De
xtrous Autonomous Robots and Humanoids»,
with sponsorship Eurobot, IEEE, CLAWAR, and CTI, HESSO
-
HEIG
-
VD (West Switzerland University of Applied Sciences),
Yverdon
-
les
-
Bains, Switzerland, May 19
-
22, 2005.


RDE
-
9

Pierre Maurer and Micael Gagnebin, "Advance
d control
structure for the autonomous mobile robot Lodur", « DARH
-
2005
-

1st International Conference on Dextrous Autonomous Robots
and Humanoids», with sponsorship Eurobot, IEEE, CLAWAR,
and CTI, HESSO
-
HEIG
-
VD (West Switzerland University of
Applied Scie
nces), Yverdon
-
les
-
Bains, Switzerland, May 19
-
22,
2005.


RDE
-
10

Stéphane Salerno and Laurent Camax, “Design of a F.I.D.O.
-
Type Mobile Autonomous Robot”, IAC
-
03
-
P.P.02 Space
Congress of the IAF (International Astronautics Federation),
Bremen, Germany, Oct
. 1
-
6, 2003


RDE
-
11

Stéphane Salerno, “Réalisation d’un robot mobile du type
F.I.D.O Rover
-

Système locomoteur”, rapp. Diplôme,
HESSO.HEIG
-
VD, Switzerland, 2002


RDE
-
12

J.
-
D. Dessimoz, Pierre
-
François Gauthey, Michel Etique,
Bernard Saugy et Andrea Vez
zini, "Serpentine
-

an Intelligent
Urban Transportation System for Passengers, with
Autonomous, Mobile Robot Properties", Conf. and Proceedings,
SMC'99
-
IEEE, Tokyo, Japon, oct. 1999


RDE
-
13

Klaus Schilling, Thorsten Krupp, CAE
-
Methods Assisting the
Design

of the European Mars
-
Rover MIDD, Proceeding IFAC
Symposium Mechatronic Systems Darmstadt 2000.


RDE
-
14

K. Schilling, H. Roth, R. Lieb, Remote Control of a “Mars
Rover” via Internet


To Support Education in Control and
Teleoperations, Acta Astronautica 5
0 (2002), p. 173

178.




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RDE
-
15

K. Schilling, L. Richter, M. Bernasconi, C. Garcia
-
Marirrodriga,
The European Development of a Small Planetary Mobile
Vehicle, Space Technology 17 (1998), p. 151
-

162.


RDE
-
16

D. Turchi, S. Trolliet, L. Bourgeois, and J.
-
M. Vulliamy, "Design
and locomotion control for a telerobot of Sojourner type", 48th
Symposium of the International Astronautical Federation,
Torino, Italy, oct. 97, paper ST
-
97
-
W.2.04 (re.) publ. by the
American Institute of Aeronautics and Astronautics,

New York,
USA


RDE
-
17

J.
-
C. Buache, «

Robotique industrielle
-
Automatisation d’un
processus industriel

», Thesis, HESSO.HEIG
-
VD, Dec. 2006


RDE
-
18

Typical Human
-
Machine Interface for interactive specification of
relative rectilinear, circular or point
Motions of a mobile robot

http://arymotion.p
opulus.ch//rub/2#O
nlineInteraction




5

Technical Proposal (Baseline)

This section describes the set of four (4) tasks that are planned for «

Engineering

» (re. point 5.1 in
ADE
-
1) in C&L

: Design. In addition, we

also describe related workpackages in RDE
-
1.

5.1

Chassis and Locomotion Design

The principle tasks are to define the optimum Rover Chassis & Locomotion system, and to design,
manufacture and test a breadboard of the chosen design, to be implemented within th
e specified
schedule. Re
-
use of existing designs is planned where possible and mentionned accordingly.

The technical proposal for design is described in the following 10 paragraphs, in a structure similar to
ADE
-
1.

5.1.1

Assessment of the Rover locomotion requ
irements

Exploration of planetary surfaces requires mobility to access the places of scientific interest. The
development of planetary rovers can be segmented into specific periods:

-

In the sixties in the USA and Russia lunar rovers, manned and


unmanne
d, were developed.

-

In the eighties large vehicles were constructed by NASA for a Mars


sample return mission, which was abandoned.

-

In the nineties small rovers for Mars and the moon have been


developed by NASA and ESA.

After 2000 the tendency of N
ASA and ESA again moved towards larger planetary rovers to be able
to cover a larger area and to exhibit more robust performance.

As in terrestrial applications, most planetary rovers use wheels. But also wheeled and tracked
vehicles have been analysed. On
ly wheeled vehicles have been operated outside Earth so far. The
main advantages of wheeled rovers are


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-

good steering capabilities to given target points,


-

energy
-
efficient mobility at relatively high speeds.

Wheeled vehicles are designed for planeta
ry gravity forces. At low gravity, rovers must be operated
at smaller velocities, in order to keep the resulting forces low to avoid bouncing. Steering capabilities
will be very much affected by uneven surfaces. Thus sensor systems have to prevent motion i
nto
areas with obstacles and crevasses, which exceed the vehicle´s tolerance limits.


The Rover locomotion requirements for all mission phases seem reasonable at this point.
Occasionally, C&L Subsystem requirements (re ADE
-
2) are very conservative (e.g. RS
-
232 serial
port), and in general a large freedom is wisely left for system optimization in the perspective of
excellence in goal achievement (number of wheels, rigid or flexible state, type of actuators, etc.).

Compared to our past realizations, the requi
rements for this project are conservative in many points

:

-

The current plans as resulting from Phase A efforts and more have led to the current ESA
breadboard (made in 2006) which has motors (Maxon) and structural elements (Rexroth) which are
similar to

the ones we had on the FIDO type robot we had built and operated in 2002

; the gear ratio
is very similar as well (about 1'700

:1) and probably the position encoders were the same as well.

-

For control, our loops were much faster, and we have implement
ed with success overall
locomotion strategies on several different platforms, with very good performances (Serpentine,
Sojourner
-
type robot, FIDO
-
type robot, autonomous mobile platforms such as Lomu or RH1
-
Y for
example). Our multiagent kernel, Piaget, has

an extremely high level of granularity, is simple, small,
and has been implemented in various contexts

: Windows, DOS, on ordinary PC’s or even, with
Piaget
-
light, in C on an integrated PC (IPC). This could also easily be done in the context of the
propos
ed computing environment for this Exomars Phase B1 project.

Nevertheless, several aspects require more attention, not to mention the very tight overall schedule,
and these include in particular the following ones, mostly related to flight conditions:

-

Hel
p has to be sought for thermal aspects,

-

The flight conditions for computing resources (HW, SW, incl. IO's) have not been experimented yet
and even to some extent are still underspecified.

-

To consider as proposed by RCL and MDR (re RDE
-
4) additional mot
ricity for walking, is very
challenging. Apparently this could be relatively easy schieved if only small variations about
equilibrium values were tolerated. The dynamic range for walking however cannot easily be
restricted, because in moving conditions, i
n particular when moving on slopes with rocks, the
variation of limit values may very much vary.

5.1.2

Assessment and trade
-
off of alternative C&L concepts

Our experience in testing chassis structures kinematically and with dynamic properties show that
MER
-
type

rocker bogies have excellent stability properties and relative weight qualities. A possible
improvement might be brought by an additional dof on each side, for programmable outside rotation
of central leg, for two purposes

: improved stability on slopes t
ravelled sidewise, and possibility for
wheels to travel on different path, probably strongly reducing the (unwanted) depth of penetration of
wheels in soft grounds.


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Figure
5.1
-
1
:
RCL type E, with walking ca
pability, from RDE
-
4. In the current proposal the RCL
-
E is
the basic choice, but not with the displayed walking capabilities however.

Nevertheless at this point our strategy would be to pursue in as much as possible the recent options
following Phase A (RC
L
-
E), with the primary goal of delivering in time a functional and reliable
subsystem, allowing for progress in coordinated next phases (to start with

: integration of locomotion
and navigation). Following MDR recommendations, the 6x6x6x6W
(WheelsxWheelDri
vesxSteeringWheelsxWalkingWheels) solution might be attempted. We think
however preferable to follow the advice Sir Martin Sweeting once gave, as a recipe for success

:
«

avoid the nice
-
to
-
have’s

».

For reasons of weight and reliability, we propose to pro
duce the simpler 6x6x4x4W solution,
furthermore with the additional restriction that the «

walking

» mechanism should be used only once,
for unfolding legs before egress (during flight phase, legs must be folded because of the limited
volume avaible). Dur
ing operation, the legs should then be locked and passively configured.

Anyway, notice, as experimented in our simulations and published e.g. in RDE
-
6, that a critical
property of suspensions lies not exclusively in the type of architecture (e. g. RCL
-
E ve
rsus RCL
-
C or
MER) but in parameter values

! RCL
-
E suspension has very good obstacle passing properties when
the ratio of attachment height to between
-
wheel distance is very small, and on the contrary easily
falls ahead over small obstacles if the ratio gr
ows large. Therefore the optimum is in principle here to
have as low an attachment as the specified clearance to ground allows, and as long a distance
between wheels as stowing volume allows.

In as much as the primary goal is secured, better alternatives t
o known solutions will be
incrementally proposed, and if the Client approves, integrated to subsequent steps of modified plan.

5.1.3

Adaptation and validation of analytical locomotion performance evaluation tools

In principle no specific evaluation tools need b
e defined, except for what is integrated in software
design for Phase B1 activities.

5.1.4

C&L subsystem definition and design optimization

The Chassis and Locomotion Breadbord is organized as shown in Fig. 5.1.1

Struct ural
f rame
Suspension
Mechanism
Wheels
Traction and
steering drives
Localisation
sensors
Elect romechanical Assembly
Sof t ware
Package
Comput er
Hardware
Locomotion syst em
ExoMars Chassis&Locomot ion Breadboard

Figure
5.1
-
2
: ExoMars Rover Chassis & Locomotion system and subsystems


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This organisation reflects the requirements [ADE
-
2]. For design optimization, the starting points are
mainly the external references (ADE
-
2, RDE
-
3.,RDE
-
5) an
d the internal references (e.g. RDE
-
12,
RDE
-
7, RDE
-
10, RDE
-
6, RDE
-
9)

5.1.5

Detailed locomotion performance prediction and evaluation

Detailed locomotion performance prediction and evaluation (incl. locomotion capabilities, mass,

stability, power and rover mech
anical loads) will be performed, most probably confirming the
required specifications.

5.1.6

Assessment of Electrical, Thermal, TM/TC and structure requirements of the C&L
subsystem

Assessment of Electrical, TM/TC and structure requirements of the C&L subsystem,

for all mission
phases will be performed.
For thermal aspects, additional partners will be considered.

5.1.7

Generation of reduced mechanical FEMs and thermal TMM/GMMs

Generation of reduced mechanical FEMs and thermal TMM/GMMs of the locomotion subsystem (for
i
ntegration into rover vehicle models) will be considered.

5.1.8

Consolidation of the C&L Subsystem Requirement Specification

Consolidation of the C&L Subsystem Requirement Specification, in terms of power, heat and mass
will be done.

5.1.9

Identification and analysis

of critical technologies for the C&L subsystem

Identification and analysis of critical technologies for the C&L subsystem is an essential purpose of
Phase B1 Breadboard.

The main point is to have a functional system, where other contributions (primarily
navigation) can
be tested in real
-
size conditions. Next is the reasonable certainty that budgets in terms of mass and
volumes are feasible as well. Among key technological elements, «

walking

» capability, i.e. rotation
of wheels legs is a strong element.

Another one is the change of paradigm in the use of distributed
computing resources. Another one yet is the handling of possible shocks, such as a wheel slipping
from one rock to another one, with a proper damping solution

: can it be left to the ground,
or, like for
MER’s, built in the wheels, or further up, in the suspension mechanism, or even at the fixture point of
the main structural body

? Elasticity is good to reduce peak shock values, but whithout proper
damping (and losses) may lead to excessive
resonant oscillations and imprecisions. The
management of temperature and heat is another point where things are not too clear yet, and where
advices and thought must be gathered in view of future rover deployment.

The identification and analysis of crit
ical technologies will be performed all along project, integrating
new elements from experience and partner results.

5.1.10

Preparation of Programmatics for phase B2CD activitities

Preparation of Programmatics for phase B2CD activitities will be done in several s
teps.


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At this point it appears that the requirements as of [ADE
-
1] are relating to the following

product tree:

-

Breadboards (as needed)

-

Planetary Protection models (Mass, surface finish representative)

-

Structural Thermal Model

-

Qualification model,
with design and materials to be compatible with planetary

protection requirements

-

Flight model, to be developed in compliance with planetary protection

requirements

-

Flight Spares

In this list, two items deserve a special attention.

Breadboards needed
can be estimated as consisting in a single unit, but some iterations are
expected to be performed on most components, therefore a factor 1.5 to 2 in load and cost should
be estimated with respect to what would mean a single unit in the strict sense.

Flight

Spares should somewhat benefit from the modular approach taken in design. But not much
should really be expected here

: Extreme project management principles strongly reject the idea of
adding properties to components for the pure sake of addressing gener
ality. In fact each component
is best designed, produced and finally maintained if it is unique. Even though for example we have
six wheels, kinematic links and electrical wiring will differ quite a lot as for example in front, bogie
pairs are lateral, and

at the back the bogie is transverse. Consider also the 10
-
14 motor drives

:
some of them are mounted for traction, other ones for steering, and the latter for configuration.
Changes associated with stowing, handling, documentation, and traceability constr
aints, as well as
compatibility checks at each modification makes the cost of standardization in the context of a single
flight model quite high also. In summary not more than 10 to 20% can be gained in average on the
cost of spares versus originals.

Manpo
wer charges at HEIG
-
VD for next phases should be kept constant, on a much longer duration
time (about 2 years).

At the end of Phase B1, it twill become possible to consider a committing programmatic and financial
package for the complete development and op
eration phases (B2, C/D and E)

The final Specification, implementing the possible SRR RIDs, will become the starting point for the
subsequent Phase B2/C/D Rover Vehicle development activities.

Consequently, at this stage, requirements cannot be considere
d frozen and in some cases (e.g.
environmental and interface), they will become available in the course of the B1 phase, as an
outcome of the mission system and vehicle system work that runs in parallel to the work addressed
in this SoW. Due to the nature

of the B1 phase (study and breadboarding level) the incorporation of
the results of the system level design into the Rover C&L subsystem design by the E
-
Contractor is
part of the work.

5.1.11

Other remarks on C&L Design

The E
-
Contractor shall be ready to provid
e intermediate inputs and perform design and analyses
iterations following update of the requirements coming from the Astrium Ltd.

The E
-
Contractor shall undertake all the activities necessary to accomplish the engineering tasks of
Phase B1 in accordance
with the Rover Vehicle Chassis and Locomotion requirements provided in
AD.1 and its applicable documents. The E
-
Contractor shall perform such activities for the three
Rover scenarios as defined in section 1.2. The E
-
Contractor shall contribute providing a
dequate
inputs to the Vehicle system specifications definition.

In support to the design tasks, the E
-
Contractor shall perform all the necessary analyses required to
substantiate the design and demonstrate compliance to the applicable requirements as per
AD.1.


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The E
-
Contractor shall establish and maintain a complete set of resources budgets (mass,
power/energy, thermal dissipation, telemetry and telecommand etc.) relevant to the Rover C&L
subsystem.

The E
-
Contractor shall pay specific attention to the co
nstraints imposed during the stowed phases of
the mission, while the Rover Vehicle is inside the DM, in particular those related to stowage, packing
and subsequent deployment.

The E
-
Contractor shall generate reduced mechanical Finite Element Models (FEMs)

of the
locomotion subsystem in its stowed and deployed configuration for supply to Astrium Ltd for
integration into overall FEMs of the complete rover.

The E
-
Contractor is responsible for the determination of mechanical loads acting on the locomotion
su
bsystem and the rover body during surface operations.

The E
-
Contractor shall optimise the C&L subsystem design for minimum mass, volume and power
consumption.

Within the design of the C&L subsystem, when selecting design and components, the E
-
Contractor
shall take account of the implementation of sterilisation/cleaning procedures to comply with the
planetary protection policies defined in the Planetary Protection Policies and Requirements (AD 3 of
AD.1).

For what concerns the C&L Breadboard, a decision o
n the suitability of the relevant configuration
with the different mission scenarios shall be taken in agreement with Astrium Ltd, and AAS
-
I before
commencing the design and manufacture of the breadboard.

Moreover, the Chassis and Locomotion design and th
e breadboard shall be designed taking into
account, to the maximum possible extent, common design solutions and resources synergy between
the mission scenarios, such as to avoid duplication of effort.

5.2

Chassis and Locomotion Breadboarding

The Rover C&L De
sign Lead activity shall include the design, manufacture and testing of a
breadboard that is representative of the chosen flight design. The objective of this activity is to bring
the identified critical technology to TRL 4 to 5 (i.e. components and/or Bre
adboard validation in
relevant environment


See Annex 1).

-
Breadboarding tasks

-
Locomotion Breadboard

5.2.1

Breadboarding tasks

The breadboarding tasks include:

-

Definition of Breadboarding approach and use of facilities

-

Definition and detailed design of
the C&L Breadboard, including production of a breadboard
specification derived from the requirements in AD.1.

-

Procurement of all parts and materials necessary for the Breadboarding activity, including the
definition and procurement of any necessary Grou
nd Support Equipment (GSE) to support the
transportation, and operation of the C&L Breadboard.

-

Functional Commissioning of the C&L Breadboard.

-

Performance testing and characterisation of the C&L Breadboard (see detail in AD.1)

-

Definition of a poss
ible TRL upgrade program for the C&L subsystem elements, indicating at
what stage they can become part of the overall Vehicle design, development and verification
programme.


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5.2.1.1

Definition of Breadboarding approach and use of facilities

Parts will be bought w
hen possible, using major suppliers as described in Vol 2 and other (COTS).
For the rest they will be produced at HEIG
-
VD or RUAG, or subcontracted according to performance
optimality (delays, quality, cost).

5.2.1.2

Definition and detailed design of the C&L Bread
board

Definition and detailed design of the C&L Breadboard, including production of a breadboard
specification is derived from the requirements in AD.1, an is expanded in systematic way. Table 1
below shows the main elements composing the C&L Breadboard (a
s well as those composing the
Locomotion system).

5.2.1.3

Procurement of all parts and materials necessary for the Breadboarding activity

Procurement of all parts and materials necessary for the Breadboarding activity, including the
definition and procurement of
any necessary Ground Support Equipment (GSE) to support the
transportation, and operation of the C&L Breadboard.

According to tests made by other teams for ESA tests in Tenerife, C&L Breadboard transportation
requires special attention because of relative
ly large weight and size, as well as slow motion
possibilites.

5.2.1.4

Functional Commissioning of the C&L Breadboard

We shall systematically proceed to ensure that
the C&L Breadboard

functionally performs according
to the documented design intent and the operatio
nal needs, and that specified system
documentation and training are provided to the facility staff.

5.2.1.5

Performance testing and characterisation of the C&L Breadboard

Performance of the C&L Breadboard shall be tested and characterized systematically, according

to
details in AD.1 and the prepared Test Plan..

5.2.1.6

Definition of a possible TRL upgrade program for the C&L subsystem elements

In asmuch as project development allows, a TRL upgrade program will be defined for the C&L
subsystem elements, indicating at what s
tage they can become part of the overall Vehicle design,
development and verification programme.

5.2.1.7

Other remarks for Breadboarding tasks

Our Breadboard shall be as far as is practical, form, fit and function compatible with the envisaged
Flight Design so fa
r as to reproduce the main features of the design that need early demonstration in
order to assess the system performance and reliability.

5.2.2

Locomotion Breadboard

An overview of the Locomotion Breadboard is shown in Fig. 5.2.
-
1.


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Struct ural f rame
Suspension
Mechanism
Wheels
Traction and
steering drives
Localisation
sensors
Elect romechanical
Assembly
Sof t ware
Package
Comput er
Hardware
Locomotion syst em
ExoMars Chassis&Locomot ion
Breadboard

F
igure
5.2
-
1
: Overview of Product Tree

Table 1 below shows additional elements composing the C&L Breadboard (as well as those
composing the Locomotion system).

5.2.2.1

Electromechanical assembly

The main components
of the electromechanical assembly are the following:

-

A structural frame

-

Suspension mechanisms

-

Wheels

-

Traction and steering drives

-

Localisation sensors (IMU, tilt sensors, etc.)

They are presented below.

5.2.2.1.1

Structural frame

The frame will follo
w requirements and include particular settings so as to allow an easier
displacement of breadboard to various assembly and test places.

5.2.2.1.2

Suspension mechanisms

As explained above, suspension mechanisms is foreseen to be of the RCL
-
E 6x6x4x4W solution,
with t
he restriction that the «

walking

» mechanism should be used only once, for unfolding legs
before egress (during flight phase, legs must be folded because of the limited volume avaible).
During operation, the legs should then be locked and passively confi
gured.

As time allows, interesting alternatives may be explored; for example, inserting compact passive
magnetic clutches (or indexing elements) in walking joints might provide a good solution to reduce
the load of motors. During normal driving, clutches a
re blocked. When needed (cross slope driving or
initial deployement) clutches are released one by one, as the right mix of wheels rotations (moved by
powerfull wheel motors) reconfigure, one by one, the walking dofs. Of course these reconfiguring
phases sh
ould be done only if stability is garanteed. Singular states should be indentified. During
deployment, inertial effects might be used to open walking arms, by activating wheel motors.

5.2.2.1.3

Wheels

Wheels should be rigid, in order to have the best reliability, ri
gidity, i.e. higher vehicle
eigenfrequencies and increased accuracy of positioning for payload and instruments, including
navigation tools.

As learned from the team who performed trials with Bridget in Tenerife, indesirable lateral slippage
may occur with
current solutions.


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Figure
5.
2
-
2

: Sketches of lugged wheels with chevron
-
shaped or
mixed transverse and longitudinal grousers.

To limit drippage during cross slope drive lugged wheels with longitudinal or o
blique (chevron)
grousers will be considered (e. g. Fig.5.2.2)
. Probably with deeper ("smaller") profiles for longitudinal
grousers, as paddling out from landing module for egress is critical.

The size will be maximal in order to increase footprint.

For o
ptimal use of available space during stowing, motor drives will be integrated in wheels.

Experience has shown that sand is a critical cause of hazard in joint actuation, and improved
solutions with respect to current MER solutions must be searched for join
t protection and sealing.

5.2.2.1.4

Traction and steering drives

As of now the traction and steering drives are foreseen to be Maxon motors, with main gears
provided by ASSAG. The design phase will integrate the latest results in order to specify
breadboarding.

5.2.2.1.5

Loc
alisation sensors (IMU, tilt sensors, etc.)

At locomotion level, the main contributions for localisation purpose are provided by encoders on
motors and absolute sensors on all passive joints, as well as steering units.

In addition gyros provide the basis o
f an IMU.


Figure
5.2
-
3
: IMU for robotic platform, incl.
InvenSense IDG
-
300 [from RDE
-
17]

Notice that the sensors will allow not only basic motions but the also the implementation of a
caterpillar behavior (
refer for point 5.2.2.2).


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5.2.2.2

Locomotion control system

As illustrated below (5.2.2.3 Target Data) locomotion control must be carefully structured, with a
hierarchy of methods and resources addressing very different, complementary issues, such as the
followin
g: trajectory control, wheel orientation and incremental motion, point to point motion with
acceleration and speed control, as well as low
-
level servoing and position estimation from encoders.

The various points are detailed in the various paragraphs below
, but first some other remarks are still
given at this more genral level:

-

In particular, our expertise in trajectory management (e.g. RDE
-
12) and tracking, as well as
Piaget
envionment for parallelism and parallel tasks/multiagents/SOA architecture (RDE
-
7) are useful
assets.

-

An important new concept is the following one: it would be beneficial to develop and implement the
notion of virtual (instead of mechanical) tracks (re. caterpillars) in order to reduce the risk for a wheel
to sink in soft soil. It

is of course not possible to increase footprint by this approach, but nevertheless
the collective behavior of wheels can be improved in a similar way, all wheels but one contributing to
motion when the atter must simultaneously correct position or speed w
hile reducing torque below
slippage values. A similar way to optimize locomotion was practiced in our Serpentine vehicles, both
at local level, with 4 active tracting wheels, and in convoy configuration, with multiple vehicle
following each other at short
distances (re. e.g. RDE
-
12).

(I was already noted in 1997 (RDE
-
16) that wheels have a tough job of moving on soft ground since,
as easily experienced with cars on sand or snow, entering the ground induces steep local slopes for
getting out of the hole, the
refore high forces should be applied to ground elements, which slip away
with the wheel and behing, digging further the ground, instead of pulling the wheel (and vehicle) out
of ground.)

-

From another view angle, most of the locomotion control system shou
ld finally be ported on LEONS
processors, and in the framework of the architecture specifically described in the requirements (see
Fig. 5.2.4).




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Figure
5.2
-
4
:
UML class diagram of the interfaces with the Mo
tion Execution subsystem

( from [ADE
-
2] fig. 3.7
-
1.)

It is suggested in [ADE.2] that locomotion, as far as control is concerned) should be made possible
by a Motion Execution subsystem as described in the accompanyng figure

along with a graphical
represen
tation of the required interfaces
.

This Motion Execution subsystem is required to interact with other subsystems and data stores,
What follows is a definition of the minimum set of message and interfaces required to implement the
required functionality of
the Motion Execution subsystem.

It is intended that these interfaces and message will be refined and completed during the
Breadboarding activities of Phase B1.

In summary, the main components of the locomotion control sytem are the following:

-

Motion Exe
cution Manager

-

Motion Execution Kernel

-

Target Data Manager

-

Localisation Data Manager

-

Localisation Manager

-

Wheel Controller

-

Tracting Motor Assembly («

Drives)

-

Steering Motor Assembly

-

Drive Motors

-

Navigation Data manager

They are presented
below.

Notice that at least three complementary point of views can validly be adopted

: message passing,
as above, OS adapted code distribution (RTMS, on Leon processors), and possibly a multiagent
approach, of Piaget
-
type. For each of those three points o
f views a different architecture is relevant.

The Breadboard will comply with the requirements in terms of functionality, HMI , OS and language
standards as well as main and internal control interfaces.

5.2.2.2.1

Motion Execution Manager

Trajectories will be defined

at the highest abstraction level, either in the navigation subsystem, or in
the Motion Execution Manager.

The Motion Execution Manager will be a Man Machine Interface for the purposes of the
Breadboarding activities

; with the highest possible compatility

at the interface level to the Motion
Execution Kernel, to which the Navigation Subsystem will deliver commands.

For test purpose, trajectories may typically be conveniently (according to our experience) defined as
follows :

-

Select key points (x,y) on a

map,

-

Interconnect them with linear sections

-

Resample the trajectory at regularly
-
spaced intervals

-

Smooth the trajectory, iteratively until some application
-
related or vehicle
-
related, maximum
curvature constraint is met (re. JDD, Signal Process
ing 79).

-

Define local orientation (tangent angle) for each sample (x, y, alpha)

On this basis, it is easy to generate the orders towards or from Motion Execution Kernel.


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Figure
5.2
-
5
:
Typical Human
-
Mach
ine Interface for interactive specification of relative rectilinear,
circular or point motions
( from [RDE
-
18] )


Orders to be handled with the locomotion protocol to be defined, towards Motion Execution Kernel,
include the following

ones : StopMotion(Join
tNumber/all), MoveTo(X, Y, AlphaDegree),
MoveRelTo(X,Y,AlphaDegree), MoveAhead(Distance), MoveBackward(Distance),
TurnAbout(AlphaDegree), MoveForwardOnTheRight(AlphaDegree,Radius).
MoveForwardOnTheLeft(AlphaDegree,Radius), MoveBackwardOnTheRight(AlphaDegre
e,Radius).
MoveBackwardOnTheLeft(AlphaDegree,Radius).

In addition, other, configuration orders may typically include SetSpeed(MeterPerSecond),
SetAcceleration(MeterPerSecondSquare), and Reset(JointNumber/all).

A number of messages may be read from the Mot
ion Execution Kernel, reflecting status of
locomotion task (Done, CurrentJointError(JointNumber/all), Current Location,
GetSensor(SensorName/All), etc.),

Finally, the protocole manager will make sure to garantee compatibility with high
level directives, a
s
defined if Fig. 5.2
-
5.


Figure
5.2
-
6
:
Typical Intertask message exchange diagram in basic operation
(re. P.31 from [ADE
-
2] )


A possible option would be to command motion along a trajectory segment, chara
cterized by
multiple via points (e.g. FollowTrajectory(ViaPoints, N)). In practice the merit of such an approach
seems limited by the fact that the navigation subsystem would probably be capable of delivering

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better via points as progress is achieved, eit
her because new information is available (e.g. better
visibilty of obstacles) or because corrections in path following can be done (implicit compensation
for tracking erros, etc.).

5.2.2.2.2

Motion Execution Kernel

The motion Execution Kernel implements the main fu
nctionality of the Locomotion system

: «

Motion
Execution

». It will essentially convert and interpolate in time the via
-
points from the Navigation Data
into a series of Drive and Steer Motor commands.

The main input commands have been listed in the previo
us point (5.2.2.2.1Motion Execution
Manager).

From input commands, several situations must be distinguished

, corresponding each to a specific
treatment

: absolute interpolative motion, rectilinear relative motion, circular motion, point motion.

The gene
ral method for travelling on regularly spaced samples on smooth curvilinear trajectories, for
a vehicle with numerous coordinated joints, such as ExoMars Rover, is the following

:

-

match vehicle position and orientation in terms of main structure (chassis
)

-

define relative position and orientation (transformation) of each wheel or limb (thereby superposing
gait)

-

interpolation is made directly at individual wheel or limb level between so
-
defined successive
positions along trajectory





Figure
5.2
-
7
:
Principle for trajectory tracking (left) and multiple wheel coordination

(right) ( e.g. [RDE
-
10] , [RDE
-
12])

In priority, the basic input commands defined above are applicable, and each of the corresponding

situation is described below: absolute interpolative motion, rectilinear relative motion, circular
motion, point motion. While the sequential order of the motions has been logical for the user so far,
the order is noe changed for ease of implementation,


-


Rectilinear relative motion
. Conceptually, the rectilinear relative motion is the simplest, all
wheels being parallel and making the same nominal displacement. The result is a segment of
straight line.

-

Point motion
. A point motion is a motion whereb
y the vehicle rotates «

horizontally

» about its
center. For a point motion, wheels have to be oriented in such as way that their axis of tracting
motion passes by the center of rotation of the vehicle. Then the travel to be made by each
wheel along trajec
tory is proportional to their distance to the point of rotation.

-

Circular motion
. For circular motion, the center of rotation can be defined arbitrarily far on the
right or on the left of the vehicle. This distance defines he curvature radius, and its in
verse, the
(local) curvature of the trajectory.


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-

Absolute interpolative motion
. For the user, the simplest is to specify the cartesian coordinates
in the plane, along with a rotation

: X, Y, alpha. The reference frame may typically be the
lander frame (ab
solute coordinates)

; or it can be with the same ease the vehicle frame
(relative motion). In all cases, using our Amiguet’98 method, the motion is made in three
steps

: point motion for directing the rover towards goal, rectilineat motion to th goalsite,
and
point motion again in order to reach the final specified orientation (alpha).


Figure
5.2
-
8
:
Principle of the method of Amiguet for absolute interpolative motion

On this basis, all joints may receive the
ir respective target values for displacement, maximal
acceleration and top speed.

5.2.2.2.3

Target Data

The Target Data refers to the elementary motor setting required to progressively
implement the
Navigation generated path.

Caution must be given here to the actual

level considered in control hierarchy.


Figure
5.2
-
9
:
Control hierarchy for locomotion, including management of multiple wheel tracking and
steering motors


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In practice for each axis individually target pos
ition, maximal speed, and maximal acceleration are
received at relatively low pace (on the order of once per second, for ExoMars) from upper levels
(Motion Execution Kernel).

With a trapezoidal profile in speed, faster Target data must be generated by inte
rpolation, for feeding
lower
-
level wheel controllers.

5.2.2.2.4

Localisation Data

The Localisation Data consists of a fusion of all sensor data. This information is available to the
Navigation subsystem; however, the sensor fusion is performed at the Locomotion sub
system level
by the Localisation Manager subsystem.

See next point.

5.2.2.2.5

Localisation Manager

The Localisation Manager is where Sensor data fusion occurs.

A careful integration of all executed motions can be done bortton
-
up, thereby yielding a good
estimate of
current vehicle location, to be confronted with target data. Computation should be done 6
times

, each time neglecting one of the wheels. By this approach, wheels that happen to significantly
differ from the average may be specially treated, with compensat
ion of slippage.

This opens the possibility of adaptive behavior

: extra mileage for slipping wheels, or on the contrary
reduction of torque in order to avoid digging holes.

5.2.2.2.6

Wheel Controller

The Wheel Controller is responsible for instantaneous, individual

control of each joint, i. e. 10
motors. On the basis of displacement, velocity and acceleration parameters, instantaneous targets
values are computed and individually fed to lower level, closed
-
loop controllers .

In addition, encoders are read and incre
mental signals are processed at high rate (10 microsecond).
And output signal are generated in terms of PWM signals on power amplifiers for motors.

5.2.2.2.7

Drive Motors

The Drive Motors refers to the hardware implementation of the drive mechanism.
This includes
po
wer electronic circuits and encoder signals.

5.2.2.2.8

Steer Motors

The Steer Motors refers to the hardware implementation of the steering mechanism. This includes
power electronic circuits and encoder and absolute position signals.

5.2.2.2.9

Navigation Data

The Navigation Da
ta refers to the path data generated by the Navigation subsystem. For the
Breadboard it will be included as part of the MMI.
See details above in this 5.2.2. section.

5.2.3

Other remarks on C&L Breadboarding

The camera systems are not considered part of the loc
alisation sensors.

The Contractor shall identify the worst design cases, to be agreed with RUAG, to be used for the
breadboard model design and testing.


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The B/B shall allow the implementation of design activity outcomes (both at vehicle and at C&L
level
) that can be raised either during the phase B1 itself or later on.

The Contractor shall provide test predictions by analysis of the Breadboard performance.

When not explicitly specified, the scale of the Breadboard model shall be such that demonstratio
n of
actual flight performance is possible from the test results.

The tests shall include testing on a sufficiently representative terrain in terms of mobility aspects
(physical soil properties and distribution of rocks) to allow validation of the predic
tions of mobility and
stability performance on Mars. A draft Test Plan is included within the ITT Pack for guidance.

The Contractor shall prepare, issue and execute a test program for both the breadboard model and
the subassembly demonstrators (if any).

The Contractor shall prepare a test plan, perform the tests and issue a test report for the performed
breadboard tests.

In the test report the Contractor shall correlate the test results with test predictions made by analysis,
confirm the expected perfor
mance and indicate relevant impact on the system design.

The Contractor shall prepare and issue a breadboard user manual to allow potential reutilisation of
the items in subsequent phases.

The Contractor shall foresee, for the breadboard activity, a Br
eadboard Design Review (BB DR),
Test Readiness Review (TRR) and a combined Test Review Board (TRB)/Delivery Review Board
(DRB). This final combined review shall be convened to declare the completion of the breadboard
activity and take a final decision on
the related enabling technology to be adopted and further
developed in the following project phases. This shall be achieved by analysing the results of the
breadboard testing, their consequences on the mission design and the results of the Aurora
Programme

R&D activities, to be documented in an appropriate document, part of the Design
Justification File.

Astrium Ltd, as Vehicle System Lead, will prescribe an on
-
board Processing architecture (see AD.1)
for the Locomotion Breadboard, to enable subsequent int
egration of the Rover Navigation
functionality. The processing hardware will be provided as free issue from a breadboard integration
procurement activity being in run in parallel to the C&L activities.

All the software elements of the onboard locomotion
will be developed as tasks within the RTEMS
operating system of the Leon processor. Astrium Ltd will provide support for this work as part of the
breadboard preparation work. It will be the task of the contractor to define and implement the
necessary alg
orithms and co
-
operate with the vehicle prime in the refinement of the interfacing
between the processing modules.


Figure
5.2
-
10
: Gaisler GRESB Spacewire Ethernet Bridge


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At this point, interfacing possibil
ities with the target system, and capabilities in terms of bandwidth
and reactivity are not clearly defined yet, therefore as a safe alternative, the baseline will ensure that
the Chassis and Locomotion breadboard will be operational by using conventional
techniques, with
the Spacewire
-
Ethernet Bridge of Fig.5.2.10 ensuring compatibility with the rest of Rover system, in
case other teams are ready in thie proposed RTEMS and Leon processor technology. It is hoped
however that an implementation closer to futu
re flight conditions will also be done during Phase B1.

In order that the software developed for the Locomotion system shall be transferable, it shall be
written in the C programming language. A description of the modules involved can be found in AD.1.

No
te: A navigation system is not part of these C&L breadboard activities

5.3

Assembly, Integration and Verification

The Contractor shall prepare the C&L subsystem AIV Plan following the ExoMars Assembly
Integration and Verification Requirements (see AD 8 of AD.
1) and taking into account Planetary
Protection requirements as specified in AD 3 of AD.1. As a minimum he shall identify:



• Model philosophy

• Verification methods (producing a Verification Matrix)

• Requirements traceability approach

• Preliminary
AIT flow.

5.3.1

• Model philosophy

The basic idea is to ensure the manufacturing of a model which will be functional at the end of the
project, in particular with the goal of receiving other key project contributions

: computing hardware,
operating systems, nav
igation implementation.

The second topmost priority is to get as close as possible to the flight version, in order that
expierence be gained so as to improve design and performances.

5.3.2

• Verification methods

Verification wil be done bottom
-
up, starting with

components and subassemblies. A natural approach
is to produce and update in systematic fashion a Verification Matrix.

5.3.3

• Requirements traceability approach

Changes in requirements will be traced by using a rigorous structure of directories and archive fi
les.
Standard tools for incremental document changes will provide the possibility to analyze all chainge
chains.

In addition, special documents with requirement matrices will help having a quick overview of main
items.


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5.3.4

• Preliminary AIT flow

.

Assembly is

made bottom
-
up.

Table.1 on right shows the main components for
Electromechanical assembly and Locomotion
system.

In this breadboard, many components are
multiple

: 6 wheels, 10 motors, 3 bogies etc.

Therefore each modular subunit must be
satisfactorily
assembled integrated and tested
before similar units are similarly assembled,
integrated, and tested.

Flows will be organized in parallel for
independent items, in particular, for mechanical
aspects, wheels, bogies, motor drive
subassemblies, and for softw
are elements
position integrators, commutators, interface
drivers, motion manager, etc.

For mechanical components as well as software
components, the design, breadboarding, and
AIT phases should be as much as possible
iterated 4 times

: in theory, in simul
ation, on
standard existing system, and finally as the
specified unit complying with requirements.

Table 1.
Main components for Electro
-
mechanical assembly and Locomotion system


Breadboard







Electromechanical assembly





Structural frame







Fra
me







Fixtures for stowing





Helpers for moving




Suspension mechanism






Bogie right






Top bar front






Top bar rear






Main fixture






Lower bar







Front vertical






Rear vertical






Passive joint sensor




Bogie left






Bogie rear





Wheels








Front right







Middle right






Rear right







Front left







Middle left







Rear left






Traction and steering drives





Traction drives







Front right








Motor








Encoder







Harm
onic drive






Amplifier






Middle right






Rear right







Front left







Middle left







Rear left






Steer Units







Front right







Rear right







Front left







Rear left





Temporary load







Computing hardware






I/O unit incl.






10x

A in








B in








Top
in








PWM Out 1+







PWM Out 1
-







PWM Out 2+



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PWM Out 2
-







Enable






4x

Position sensor





3x

Bogie position
sensor




Batteries







Power supply



Locomotion syst
em






Software Package






Application








Motion Executive







Communication unit




Coordination unit







Linear motion






Point motion






Cartesian absolut motion





Circular motion




10x

Low
-
level control loop




10x

Position

integrator





10x

Commutator







Localisation unit




Test Package





Computer hardware









Table 1.
Main components for Electro
-
mechanical assembly and Locomotion system.


5.3.5

Other remarks on C&L
Assembly, Integration and Verification

This AI
V plan shall include activities performed at unit and subsystem level.

The E
-
Contractor shall support all AIV activities performed at higher level i.e. Vehicle, Rover and
Descent Module Composite levels

The E
-
Contractor shall be compliant with the projec
t requirements traceability approach established
at system level, and in particular he shall use the DOORS/TREK tool. (In as much as the E
-
Contractor uses other tools, he shall ensure compliance for the elements necessary at higher levels)

5.4

Mathematical Si
mulation and tools

The E
-
Contractor shall use the following standard tools:

• For mechanical/structural design


MSC NASTRAN 2005 (for non
-
linear analysis ABAQUS)

• For configuration design
-

CATIA version V.

• For multi
-
body dynamic analysis


Mecano.

The HEIG
-
VD works usually with CATIA version V and SolidWoks 2006.

HEIG
-
VD is able to provide calculations with MSC NASTRAN 2005 and with ANSYS 10.0.

Part of the work will be outsourced. Abaqus structural and thermal calculations can be carried out by
LMAF laboratory from Swiss Federal institute of Technology (EPFL). HEIG
-
VD and EPFL use
software under academic license agreement. Theses softwares shouldn’t be used in this project
without permission. If needed, these softwares shall be rented. Standard
price for renting is about
20$/hour.


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Usualy HEIG
-
VD carries multibody simulations out by ADAMS/CosmosMotion or MBdyn. The
Mecano analysis shall be outsourced.

For all the design activities involving the use of other SW simulations, HEIG
-
VD shall demonstra
te
the validation of the used tools.

For locomotion analytical tools, validation shall be linked to the breadboarding activity.

6

Improvement and Optimisation

During the C&L Engineering task, optimizations will be performed to reach target requirements and

improvements will be proposed to RUAG..

The improvements will be proposed with respect to the performance, mass, functionality, cost, etc.
having in mind productivity and risk.

Possible improvements that fall outside of the normal scope of activities (cos
t & schedule) will be
discussed at review meetings and implemented only following RUAG approval.


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7

Attachments

7.1

Attachment 1

-

ISO 9001:2000 HEIG
-
VD
-
CeTT Certificate, issued by IQnet



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7.2

Selection of relevant publications

The list below includes many of the ref
erence documents quoted above but is here much more
complete.

Jean
-
Daniel Dessimoz, Pierre
-
François Gauthey and Carl Kjeldsen, "Ontology for Cognitics, Closed
-
Loop Agility Constraint , and Case Study in Embedded Autonomous Systems


a Mobile Robot with
Ind
ustrial
-
Grade Components", Proc. Conf. INDIN '06 on Industrial Informatics, IEEE, Singapore,
Aug.14
-
17, 2006, pp6.

Nicolas Uebelhart« Modelling and animation of virtual autonomous mobile robots, in physically
simulated world, for the evaluation of locomoti
on and navigation structures », Symposium A5.2.
Human and Robotic Partnerships to Realize Space Exploration Goals, International Space Congress
IAF (Fédération internationale d'astronautique), Fukuoka, Japan, Oct. 17
-
21, 2005

André Perrenoud, Pierre
-
Franço
is.Gauthey, Nicolas Uebelhart, Jean
-
Daniel Dessimoz,
"Development and Opportunities for Mobile Robots in Switzerland", IPLnet 2005: "Needs and
Opportunities for Swiss Industry", 5th national Workshop of the Swiss Network of Excellence for
Integral Producti
on automation and Logistics, IPLnet, Schloss Böttstein, Sept. 5
-
7, ISBN

Nicolas Uebelhart, Stéphane Michaud and Olivier Michel, "Modelling and animation of virtual
autonomous mobile robots, in physically simulated world, for the evaluation of locomotion a
nd
navigation structures", « DARH
-
2005
-

1st International Conference on Dextrous Autonomous
Robots and Humanoids», with sponsorship Eurobot, IEEE, CLAWAR, and CTI, HESSO
-
HEIG (West
Switzerland University of Applied Sciences), Yverdon
-
les
-
Bains, Switzerlan
d, May 19
-
22, 2005.

Nicolas Uebelhart, Florian Glardon and Pierre
-
François Gauthey, “Lomu, an Autonomous Mobile
Robot with Robust Architecture and Components", « DARH
-
2005
-

1st International Conference on
Dextrous Autonomous Robots and Humanoids», with s
ponsorship Eurobot, IEEE, CLAWAR, and
CTI, HESSO
-
HEIG (West Switzerland University of Applied Sciences), Yverdon
-
les
-
Bains,
Switzerland, May 19
-
22, 2005.

Klaus Schilling, Testing of Planetary Rovers in Earth Environments, IFAC Symposium Mechatronic
System
s, Berkeley 2002.

Pierre Maurer and Micael Gagnebin, "Advanced control structure for the autonomous mobile robot
Lodur", « DARH
-
2005
-

1st International Conference on Dextrous Autonomous Robots and
Humanoids», with sponsorship Eurobot, IEEE, CLAWAR, and CT
I, HESSO
-
HEIG (West Switzerland
University of Applied Sciences), Yverdon
-
les
-
Bains, Switzerland, May 19
-
22, 2005.

Stéphane Salerno and Laurent Camax, “Design of a F.I.D.O.
-
Type Mobile Autonomous Robot”, IAC
-
03
-
P.P.02 Space Congress of the IAF (Internation
al Astronautics Federation), Bremen, Germany,
Oct. 1
-
6, 2003

K. Schilling, H. Roth, R. Lieb, Remote Control of a “Mars Rover” via Internet


To Support Education
in Control and Teleoperations, Acta Astronautica 50 (2002), p. 173

178.

Stéphane Salerno, “Ré
alisation d’un robot mobile du type F.I.D.O Rover
-

Système locomoteur”,
rapp. Diplôme, HESSO.HEIG
-
VD, Switzerland, 2002.

J.
-
D. Dessimoz, "Is a Robot that can Autonomously Play Soccer Intelligent?", Proc. Intern. Conf. on
Intelligent Autonomous Systems, No

6, E. Pagello et al (Eds), IOS Press, co
-
sponsored by IEEE,
Venice, Italy, July 2000, pp. 951
-
958

Klaus Schilling, Thorsten Krupp, CAE
-
Methods Assisting the Design of the European Mars
-
Rover
MIDD, Proceeding IFAC Symposium Mechatronic Systems Darmstadt 2
000.

J.
-
D. Dessimoz, "Robot Task Description for Motion Control along Complex Trajectories", Proc.
Intern. Conf. on Intelligent Autonomous Systems, No 6, E. Pagello et al (Eds), IOS Press, co
-
sponsored by IEEE, Venice, Italy, July 2000, pp. 1013
-
1018

J.
-
D
. Dessimoz, Pierre
-
François Gauthey, Michel Etique, Bernard Saugy et Andrea Vezzini,
"Serpentine
-

un Système Intelligent de Transport Urbain pour Passagers, avec des Propriétés de

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Robots Mobiles Autonomes", Conf. et Actes du Congrès IEEE Francophone pour
l'Automatique,
CIFA
-
IEEE, Lille, France, Juillet 2000

J.
-
D. Dessimoz, Pierre
-
François Gauthey, Michel Etique, Bernard Saugy et Andrea Vezzini,
"Serpentine
-

an Intelligent Urban Transportation System for Passengers, with Autonomous, Mobile
Robot Propertie
s", Conf. and Proceedings, SMC'99
-
IEEE, Tokyo, Japon, oct. 1999

J.
-
D. Dessimoz, F. Schnegg, D. Ceppi and F.G. Casal, "Tech
-
Spa, a personal tutoring environment
for space techniques", 49th International Astronautical Congress, Intern. Astron. Federation,
M
elbourne, Australia, 28 sept.
-
2 oct. 1998; Proc. publ. by the American Institute of Aeronautics and
Astronautics, New York, USA.

J.
-
D. Dessimoz, P.
-
F. Gauthey, M. Etique, A. Rotzetta, B. Saugy, and F. Dräyer, "Automatic Path
Generation and Steering for a
New, Intelligent Urban Transportation System", Proc. ICAM'98, 3rd
International Conference on Advanced Mechatronics,
-

Innovative Mechatronics for the 21st Century,
Okayama, Japan, Vol.2, pp. 762
-
767, 3
-
6 Aug. 1998.

J.
-
D. Dessimoz, P.
-
F. Gauthey, M. Etiqu
e, C. Yechouroun, and B. Saugy, "Automatic Guidance and
Collision Avoidance for “Serpentine”, a novel City Transport System", Proc. 31st Intern. Symp. on
Automotive Technology and Automation (ISATA), vol. "Intelligent Transportation Systems and
Telemetrics
", Düsseldorf, Germany, 2
-
5 juin 1998, pp. 441
-
448 .

K. Schilling, Teleoperations for Planetary Rovers and Industrial Spin
-
off Applications, in : S.
Rondeau (ed.), Proceedings 1st IFAC Workshop on Space Robotics, Montréal 1998, p. 25
-

30.

L. Richter, K.
Schilling, M.C. Bernasconi, C. Garcia
-
Marirrodriga,

Mobile Micro
-
Robots for Scientific Instrument Deployment on Planets, Journal of Robotics and
Autonomous Systems 23 (1998), p. 107
-

115.

K. Schilling, Autonomous Navigation of Rovers for Planetary Explora
tion, Proceedings 14th IFAC
Symposium on Automatic Control in Aerospace, Seoul 1998, p. 88
-

92.

K. Schilling, Technology Developments for Planetary Rovers and Spin
-
offs for Industrial
Applications, in: Koussoulas / Groumpos (eds.), Proceedings IFAC Symp
osium on Large Scale
Systems : Theory and Applications, Patras 1998, p. 1126
-

1131.

K. Schilling, L. Richter, M. Bernasconi, C. Garcia
-
Marirrodriga, The European Development of a
Small Planetary Mobile Vehicle, Space Technology 17 (1998), p. 151
-

162.

D. Turchi, S. Trolliet, L. Bourgeois, and J.
-
M. Vulliamy, "Design and locomotion control for a
telerobot of Sojourner type", 48th Symposium of the International Astronautical Federation, Torino,
Italy, oct. 97, paper ST
-
97
-
W.2.04 (re.) publ. by the America
n Institute of Aeronautics and
Astronautics, New York, USA.

L. Richter, K.Schilling, M. Bernasconi, Technology Development for a Mobile Instrument Deployment
Device for Mars Surface Exploration, IAF
-
97
-
Q.3.05, Turin 1997.

K. Schilling, H. Roth Sensor Syste
m and Teleoperations Concept for the Mars Rover MIDD, in:
P.Levi, Th.
Bräunl, N. Oswald (eds.) Autonome Mobile Systeme 1997, "Informatik aktuell" Springer
Verlag 1997, p. 178
-

188.

K. Schilling, Control Aspects of Planetary Rovers, Control Engineering Pr
actice 5 (1997), p. 823
-

825.

K. Schilling, L. Richter, M. Bernasconi, C. Jungius, C. Garcia
-
Marirrodriga, Operations and Control
of the Mobile Instrument Deployment Device on the Surface of Mars, Control Engineering Practice 5
(1997), p. 837
-

844.

L. R
ichter, K. Schilling, M. Bernasconi, C. Jungius, C. Garcia
-
Marirrodriga, Development of a Mobile
Instrument Deployment Device (MIDD), in : L. Demsetz (ed.), "Robotics for Challenging
Environments", Albuquerque, 1996, p. 283
-
289.

K. Schilling, C. Jungius,

Mobile Robots for Planetary Exploration, Control Engineering Practice 4
(1996), p. 513
-

524.

----