Design and Use of CSP Meta-Model for Embedded Control Software - - PowerPoint PPT Presentation

Design and Use of CSP Meta-Model for Embedded Control Software Development

Communicating Process Architectures 2012 Maarten Bezemer, Robert Wilterdink and Jan Broenink

Robotics and Mechatronics, University of Twente, The Netherlands

CSP Meta-Model for Embedded Control Software Development 2

Outline

• Introduction
• CSP Meta-Model
• Use Case
• Example
• Conclusions and Future Work

Demo afterwards!

CSP Meta-Model for Embedded Control Software Development 3

Introduction - Context

• Model-Driven Design tools help with development of complex

software

• CSP helps with development of concurrent software
• The combination helps with complex concurrent software
• Eg embedded control software for large(r) robots

CSP Meta-Model for Embedded Control Software Development 4

Introduction - Meta-Models

• Constituting elements of models is required
• Multiple tools (of a tool suite) need knowledge of the models
• Interchangeable models within a community
• A meta-model describes the format of a model
• A meta-meta-model describes the format of a meta-model
• etc.
• Models that conform to a meta-model use format that is known
• n before-hand
• No existing CSP meta-model available

with a focus on graphical modelling

CSP Meta-Model for Embedded Control Software Development 5

Base Meta-Model

• Modular design
• Base Meta-Model
• Component-Port-Connector (CPC) implementation
• Usable for multiple types of models
• Graph based models
• Communication based interfaces to external tools
• Basically any model having 'communicating' objects

BaseObject

name parent ...

BasePort BaseRelation BaseLink BaseDiagram IBaseContainerObject BaseModel

sub-model 0..1 parent links 0..1

• bjects

* 1 link ... ports container 1 1 * 2 relatedObjects

<<derived>>

2..*

CSP Meta-Model for Embedded Control Software Development 6

CSP Meta-Model

• Base Meta-Model + CSP constructs

CSPProcess CSPCompositionalGroup

groupedRelations

CSPCompositionalObject

relations

2 0..*

CSPCompositionalRelation

compositionalObjects group type

0..1 1..*

BaseObject BaseRelation

Base Meta-Model CSP Meta-Model

name ... relatedObjects 2..*

CSPWriter CSPReader

port variable

CSPPortVariableProcess BaseLink

ports

<<derived>>

CSPChannel

bufferSize

CSP Meta-Model for Embedded Control Software Development 7

CSP Meta-Model details

• Strict border between Base and

CSP Meta-Models

• Convenient for tools/editors
• All CSP objects/processes are

based on same CSP base object

• Even groups
• BaseRelation defines ANY relation
• Used to define compositional relations
• BaseLink defines a communicational relation
• Used to define communication channels

CSPProcess CSPCompositionalGroup

groupedRelations

CSPCompositionalObject

relations

2 0..*

CSPCompositionalRelation

compositionalObjects group type

0..1 1..*

BaseObject BaseRelation

Base Meta-Model CSP Meta-Model

name ... relatedObjects 2..*

CSPWriter CSPReader

port variable

CSPPortVariableProcess BaseLink

ports

<<derived>>

CSPChannel

bufferSize

CSP Meta-Model for Embedded Control Software Development 8

Use Case - TERRA

• Twente Embedded Real-time Robotic Application
• Eclipse based tool suite
• CSP Editor
• Model validation
• Model transformation
• CSP/FDR

→ Formal verification of model

• C++/LUNA →

Towards on target execution of model

CSP meta-model

(1.1.2)

CT meta-model FDR CSP meta-model Co-simulation engine

(3.3)

CSPm model CT model CSP model C++ code LUNA frame- work

+

conforms to conforms to conforms to

M2M (3.2) M2T

(3.1) based on based on

DE verification Simulation / CT verification Realisation

CSP Meta-Model for Embedded Control Software Development 9

Use Case – CSP Editor

• Graphical representation similar to gCSP
• More compact models, due to some changes

v

SYSTEM IO CONTROLLER

*

TILT SAFETY PAN

!

period

CSP Meta-Model for Embedded Control Software Development 10

Use Case – Model Validation

• Validation in editor
• Rules are defined by Meta-Model

'What to fill in where'

• Addition rules for transformations
• Keeps models compliant for model transformation
• Compatible with specific target transformation rules
• Object names must be correct and unique (CSP and C++ LUNA)
• Sub-models must be defined (CSP)

c

• n

t e x t C S P P r

• c

e s s { c r i t i q u e h a s S u b m

• d

e l { g u a r d : C

• d

e G e n D e s c r i p t i

• n

. i s U n d e f i n e d ( )

• r

C

• d

e G e n D e s c r i p t i

• n

= = " C S P " c h e c k : s e l f . s u b m

• d

e l . i s D e f i n e d ( ) m e s s a g e : " C S P c

• d

e g e n e r a t i

• n

w i l l f a i l : " + s e l f . n a m e + " d

• e

s n

• t

h a v e a s u b

• m
• d

e l s e t " } }

CSP Meta-Model for Embedded Control Software Development 11

Use Case – Model transformation

• Possible to use external expert tools
• FDR for formal verification of the models
• No need to reinvent these external tools!
• Put the models to actual use
• C++/LUNA code generation to execute model on target
• Prevent errors due to manual conversion of correct models

(The demo afterwards will show actual examples)

CSP Meta-Model for Embedded Control Software Development 12

Use Case – Model transformation

• Representation of model in CSP (FDR)

CSPm Meta-model representation Additional Attributes

p = ... CSPProcess CSPCompositionalGroup groupedRelations: relations that are grouped channel c CSPChannel ports: two connected ports / processes datatype <type> = <name> CSPVariableDescription

name: name of the variable type: boolean, integer...

c ! <var> CSPWriter

variable contains data link: channel to write to / read from

c ? <var> CSPReader p ; q CSPCompositionRelation type = SEQ or PAR or ALT compositionalObject: the two related objects p || q CSPCompositionRelation p [] q CSPCompositionRelation if-statement CSPRecursionProperty expression: true when another loop is required

CSP Meta-Model for Embedded Control Software Development 13

Example

• Corresponding CSP (FDR) code available in paper
• Real-life examples
• JIWY and Production Cell available

(JIWY will be showed in the demo afterwards)

v

APPLICATION THREAD2

*

READERS Calculations2 THREAD1

*

WRITERS Calculations1

!

firstValue

!

secondValue

?

readValue

?

readValue

! ?

Compositional Group Recursion Variable definition v

*

Writer Guarded Reader

LEGEND

<name>

<variable> <variable>

CSP Meta-Model for Embedded Control Software Development 14

Conclusions

• CSP Meta-Model usable to store CSP related models
• TERRA tool suite makes use of CSP Meta-Models
• Editors
• Validation
• Transformations to plain text
• Actual suitable for Embedded Control Software Development
• JIWY and Production Cell models are designed
• Used by students for their assignments

CSP Meta-Model for Embedded Control Software Development 15

Future Work

• Better integration between external modelling tools and TERRA
• 20-sim suitable for physics modelling
• Directly integrate 20-sim models as CSP sub-models
• Building blocks
• Provide standard Control Software functionality
• Generic Architecture Component as a template/skeleton block
• Simulation and co-simulation capabilities
• Better understand of models
• Able to test a control model using a dynamics model of the plant

CSP Meta-Model for Embedded Control Software Development 16

“Hopefully a standard meta-model will emerge that is suitable for the needs of the community and helping to improve interaction between multiple disciplinaries within the community.”

• Standard storage format
• Interchangeable with the tools developed within our community
• Tighter cooperation!

CSP Meta-Model for Embedded Control Software Development 17