Download Pattern Oriented Analysis and Design (POAD)

OOA Case Study:
Pacemaker
West
Virginia
University
 A cardiac Pacemaker is an implanted device
that assists cardiac functions when the
underlying pathologies make the intrinsic
heartbeats low or irregular.
 The Pacemaker runs in either a programming
mode or in one of the operational modes.
 During programming, the programmer specifies
the type of the operational mode.
 The operational mode depends on whether the
Atrium (A), Ventricle (V), or both are being
monitored or paced.
Case Study: Pacemaker
West
Virginia
University
 The programmer also specifies whether the pacing
is inhibit (I), triggered (T).
 For example in the AVI operation mode, the
Atrium portion (A) of the heart is paced (shocked),
the Ventricular portion (V) of the heart is sensed
(monitored), and the Atrium is only paced when a
Ventricular pulse does not occur
Case Study: Pacemaker (continued)
use case Diagram
West
Virginia
University
Programmer
Programming mode
<<Extends>>
<<Extends>>
<<Extends>>
<<Extends>>
<<Extends>>
AVI operation
AAI operation
VVI operation
Heart
AAT operation
VVT operation
West
Virginia
University
Context Class Diagram
DoctorProgrammer
Programming
Magnet
Pacemaker
ObservePaceMaker
Heart
PatientsHeart
Observer
Needed for
verification
purposes
West
Virginia
University
Lower-level Class Diagram
Reed_Switch
CommEnableCoil
commEnable_G
CoilComm
Communication_Gnome
CommChamber_A
CommChamber_V
Coil_Driver
Atrial_Model
Ventricular_Model
Pacemaker (continued)
West
Virginia
University
AVI Sequence Diagrams
Refractory “Initial”
Atrial
Ventricular
Refracory
Refractory
1: RefTimeOut
1.1: VrefractDone
Waiting
Waiting
Pacemaker (continued)
West
Virginia
University
AVI Sequence Diagrams
Sensed
Atrial
Ventricular
Waiting
Waiting
Heart
1: VSense
1.1: GotVSense
Reset
Sense
Timer
Waiting
Waiting
Pacemaker (continued)
West
Virginia
University
AVI Sequence Diagrams
Unsensed
Atrial
Ventricular
Waiting
Waiting
1: SenseTimeOut
1.1: APaceStart
Pacing
Pacing
2: Pace
3: PaceTimeOut'
3.1: APaceDone
Refractory
Refractory
Heart
Case Study: Pacemaker
(continued)
Atrial statechart
West
Virginia
University
Case Study: Pacemaker
(continued)
Atrial statechart
initialize
Off
ToOn
ToOff
On
West
Virginia
University
Case Study: Pacemaker
West
Virginia
University
(continued)
Atrial statechart
ToOn
ToOn
ToOff
A_Self_inhibited
Idle
ToInhibited
ToAVI
ToTriggered
A_AVI
A_Self_triggered
Case Study: Pacemaker
West
Virginia
University
(continued)
Atrial statechart
ToAVI
ini tial ize
Refractory
A_Pace_Pul se_Done
Paci ng
V_Refract_Done_Received
Time_Out
Wait
V_Sense_Recei ved
Pacemaker (continued)
West
Virginia
University
AVI Sequence Diagrams
Atrial
Ventricular
Heart
Atrial
Ventricular
Heart
RefTimeOut
RefTimeOut
V Refract Done
V Refract Done
Waiting
Waiting
Waiting
Waiting
Sense Timeout
V Sense
Got V Sense
Reset Sense Timer
A Pace Start
Pacing
Pacing
Waiting
Pace
PaceTimeOut
In case of sensing a heart beat
A Pace Done
Refactoring
Refactoring
In case of not sensing a heart beat
A sequence diagram for the Programming scenario
Programmer
ReedSwitch
CoilDriver
Communication
Gnome
Atrial
ApplyMagnet
EnableComm
IDLE
IDLE
EnableComm
ToON
ToON
Pulse
Count = 1, SetTimer
Receiving
Pulse
Count++,
ResetTimer
BitTimeout
Decode(Count)
Store Bit in Byte
Byte Full?
Yes enqueue(byte)
Waiting For
Byte
Waiting for
Bit
Pulse
Count =0
Receiving
OR
ByteTimeOut
ByteTimeOut
Validating
IDLE
IsValid?
ToAVI
HerezaByte(ACK)
Yes
Processing
HerezaByte(NAK)
Waiting to
Transmit
No
Waiting to Send
Next Byte
ToAVI
Ventricular
West
Virginia
University
•Sample statechart diagram
Of the Coil Driver
West
Virginia
University
Case Study: Pacemaker
Object Interaction Diagram
West
Virginia
University