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CIRP DESIGN SEMINAR 2003 12-14 may, 2003, GRENOBLECIRP DESIGN SEMINAR 2003 12-14 may, 2003, GRENOBLE
COOPERATIVE TOOLS FOR SPECIFICATION AND MODELLING OF COMPLEX SYSTEMS
Faiçal Miled, Denis Choulier, and Michel Ferney
Laboratoire M3M
Université de Technologie de Belfort-Montbéliard - 90010 Belfort Cedex (France)
Phone: 03 84 58 33 40 – Fax: 03 84 58 31 46
{faical.miled, denis.choulier, michel.ferney}@utbm.fr
University of technology of Belfort Montbéliard - http://www.utbm.frM3M LABORATORY
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Problem
Functional specification
Structural modelof the passive part
Validation of the structural model of the passive part
Control and simulations
Functional validation of the active part
Cla
rifi
cati
onC
once
ptu
alTools
Matrixial table
Petri nets
Bond graphs
Bond graph
simulation tools
….
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INDEX OF THE PRESENTATION
University of technology of Belfort Montbéliard - http://www.utbm.frM3M LABORATORY
II. SPECIFICATION APPROACH
QUANTITATIVE SPECIFICATION:
QUALITATIVE SPECIFICATION:
ACTIVE PART VALIDATION:
METHOD:
VI. CONCLUSIONS AND PROSPECTS
I. CLASS OF THE STUDIED SYSTEMS
III. APPLICATION: Automatic transmission of a scooter
IV. FUNCTIONAL MODELLING BY PETRI NETS
V. NEXT STAGE OF DESIGN PROCESS: Conceptual design
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Technical_System j
SUj SUj TRj
TRj WU
CUjCUj
Need Functions
Energy
HYBRID SYSTEM
I. CLASSE OF THE STUDIED SYSTEMS
ARCHITECTURAL DESCRIPTION:
Technical_System i
SUi SUi TRi
TRi WU
Need Functions Energy
* Power link
SU: Source Unit
TR: TRansmission
WU: Work Unit
CUiCUi
* Informations flow
CU: Control UnitTU
TU: Transitions Unit
LEGENDE
M3M LABORATORY
Active partActive part WU Passive part Passive part
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Technical_System j
SUj SUj TRj
TRj WU
CUjCUj
Need Functions
Energy
HYBRID SYSTEM
I. CLASSE OF THE STUDIED SYSTEMS
ARCHITECTURAL DESCRIPTION:
Technical_System i
SUi SUi TRi
TRi WU
Need Functions
Energy
CUiCUi
TU
M3M LABORATORY
Active partActive part WU Passive part Passive part
SD: Set to be Designed
SDi
SDj
TU manage discrete behaviour, its design depends on technological criteria
CUs manage continuous behaviour, their design depends on control criteria
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DIRECTIVES:
For hybrid system:
TRs are to be specified: They complete passive part (SUs and WU are preset )
CUs and TU are to be specified: They form the active part
Designers must establish strong interaction between passive and active parts: Passive part must verify control criteria
Our paper presents a methodology to establish coherent specifications of the SDs and TU
M3M LABORATORY
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SPECIFICATION
SDs , TU
The analyse of:
• SUs: Depends principally on its power characteristics;
• WU: Represents a translation of need functions;
II. SPECIFICATION APPROACH
An approach based on the states and transitions: Behavioural functions
The system to be conceived must reach operating states and ensure transitions.
SUs WU
ANALYSE
M3M LABORATORY
The specification of:
• SDs and TU: Deduced from the analyse of SUs and WU.
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Objective: Identification of discrete behaviour
Means: Study transitions between states
- Supported by the use of a symbolic vocabulary to predict the system behaviour
- It represents the first level of abstraction for specifying system
QUALITATIVE SPECIFICATION:
QUANTITATIVE SPECIFICATION:
Objective: Study the continuous behaviour of each technical system
Means: Quantify states and transitions
- Supported by a quantification of states with specific parameters in relation with
power components
- It represents a second level of abstraction for specifying system
M3M LABORATORY
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In order to realize design, the transition is:
The pre-existent elements acts such that the transition:
AND Exist Possible Impossible
Desired Ø
Not desired
SU
CONFLICT
CONFLICT
WU
TABLE OF CONSISTENCES:
NATURE OF TRANSITIONS:
M3M LABORATORY
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SU WU
nature of transitions between states of SU
States of WU
States of SU
nature of transitions between states of WU
States and nature of transitions
between states of TR
MATRIXIAL TABLE: A COOPERATIF TOOL
Ew1
Ewm
Ee1 Een
0
M3M LABORATORY
X
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III. APPLICATION: Automatic transmission of a scooter
TR
SU
Existent elements:
* SU: Thermal engine
* WU: Back wheel
WU
The user instructions:
* Desired speed with maximum efficiency;
* Maximum speed;
* Disconnect engine.
Engine will be considerate as a modulated source: Modulation will be managed by CU(s)
We must control engine speed and Back Wheel Speed
TRANSMISSION ENVIRONMENT AND EXPRESSION OF THE NEED:
M3M LABORATORY
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0
SU
WUIdling engine
Ee2
Generator engine Ee3
Free wheel Ew1
Driving wheelEw3
Receiving wheel Ew2
Stand by engine Ee1
X X
0
0 0
0
0 X
X
0
0
0 1 1
0
1
1
0
Qualitatif states Matrixial Table
QUALITATIVE SPECIFICATION:
Receiver engine Ee4
Qualitative specification needs basic knowledge's of the system
The analyse of SU and WU implies SD and TU qualitative specification
M3M LABORATORY
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QUANTITATIVE SPECIFICATION:* The quantitative states related to Ee3 are:
– Ee3,1: Maximum power;
– Ee3,2: Maximum power engine efficiency.
e
Pe
0
Maximum-Power
X
0
0
0
Ee31
Ee32
Ew21
Ew22
Ew23
SU WU
X
X
p_max
1
m
Te
e0
Maximum-Power efficiency
r_max
1
m i: engine load
M3M LABORATORY
* The quantitative states related to Ew2 are:
– Ew21: Maximum torque applied to the wheel;
– Ew22: Follow a speed instruction;
– Ew23: Reach maximum speed.
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IV. FUNCTIONAL MODELLING BY PETRI NETS:
Petri Net is a hierarchical modelling tool:
We affect each qualitative state to Petri Net model place
We affect each quantitative state to a substitution place
METHOD:
P2 P3
T1
T2
T3T4
T5
P1
P21
P22
P23
T22
T21
T23
T24
T25
P23
P2
Hier-level Petri Net: Qualitative modelling Low level Petri Net: Quantitative modelling
M3M LABORATORY
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P1
P21
P22
P23
T22
T21
T23
T24
T25
P3
T1
T4
T3T5
P23
T2
P2
Validation is made by:
• Study of structural properties of Petri Net: Liveliness and accessibility;
• Simulation of different use cases.
ACTIVE PART VALIDATION:
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V. NEXT STAGE OF DESIGN PROCESS: Conceptual design
Se : Cm
m
I:Jm
1
: SeCpr
r 1
R(r)
Cm
m
I:Jm
1
I:Jeq
M.T.F .. m
0
MSe :u2
y1
y2
SU TR WU
MSe :u1
M3M LABORATORY
P3
T5
P1
P21
P22
P23
T22
T21
T23
T24
T25
T1
T4
T3
P23
P2
T2
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VI. CONCLUSIONS
A cooperative tools for the synthesis of a valid technical specifications is proposed;
The multidisciplinary specification approach is based on a "state-transitions" language;
Matrixial tables allow for the visualisation and the application of consistence's rules which guarantee the coherence with the existing parts;
The passage to Petri Net models permits the validation of the active part;
The generation of TRs alternatives design should take into account control criteria, which are verified directly on bond-graph model;
Petri Net and bond-graph models form a complete virtual prototype of the application;
This prototype also makes possible to carry out qualitative, then quantitative simulations.
M3M LABORATORY
AND PROSPECTS