代写COMPSYS 705 Assignment 1 (part 1)代做Python编程

COMPSYS 705 Assignment 1 (part 1)

UPPAAL  Modeling and Verification

1   DDD mode pacemaker (Weighting: 15%)

Your task is to create a model of DDD mode pacemaker using UPPAAL. The created modelshall be verified using UPPAAL.

1.1    Model Description

The heart model, including two components of “Random_Atrium” and “Random_Ventricle”, has been given as shown in Fig. 1.

•    Random_ Atrium:

o Inputs: AP;

o Outputs: APulse;

o Local clocks: x, x ∈  [Aminwait, Amaxwait]

o constint Amaxwait = 1200;

o const int Aminwait = 1;

•    Random_ Ventricle:

o Inputs: VP;

o Outputs: VPulse;

o Local clocks: x, x ∈  [Vminwait, Vmaxwait]

o const int Vmaxwait = 1200;

o const int Vminwait = 1;

Fig. 1. A random heart model.

A DDD mode pacemaker is capable of sensing and pacing both the atrium and ventricle. The timing constraints include [1]:

•    AEI: Atrial Escape Interval. This describes the maximum time interval between a ventricular event and the corresponding atrial event.

•    AVI: Atrial Ventricular Interval. This describes the maximum time interval between an atrial event and the corresponding ventricular event.

•    VRP: Ventricular Refractory Period. This defines the resting period for the ventricle after each

ventricular event. Physiologically, ventricular events are not detectable by the pacemaker during the resting period. That is, if VPulse, generated by the heart model, occurs within VRP, it will be   ignored by the pacemaker.

•    PVARP: Post Ventricular Atrial Refractory Period. This defines the resting period for the atrium after each ventricular event. Physiologically, atrial events are not detectable detected by the    pacemaker during the resting period. That is, if APulse, generated by the heart model, occurs   within PVARP, it will be ignored by the pacemaker.

•    URI: Upper Rate interval. This indicates the minimum time interval between two consecutive ventricular events.

•    LRI: Lower Rate Interval. This indicates the maximum time interval between two consecutive  ventricular events. In dual chamber mode, LRI time interval equals the summation of AVI and  AEI. It serves as the lower bound for the heart rate, and hence the value of LRI is greater than URI.

Fig. 2 shows examples how the DDD mode pacemaker works at some heart conditions.

Fig. 2. The timing diagram of the DDD mode pacemaker [1].

•    Waveform 1 indicates a normal heart behavior. We could observe that the related AVI timers stop before expiry, which shows a normal synchrony between an atrial event and the following ventricular event. Likewise, the behavior. of AEI shows a normal synchrony between ventricular event and the coming atrial event.

•    Waveform. 2 presents the following situation where an artificial pulse (VPace) will be generated by the pacemaker if an intrinsic ventricular pulse is not sensed within the AVI interval. Also the  LRI requirement is not violated.

•    Waveform. 3 features a situation where both AEI and AVI are expired. Consequently, to achieve the LRI requirement, both APace and VPace are produced.

•    Waveform. 4 presents an atrial event that is earlier than usual. It may cause a temporary fast ventricular rate if there is no upper limitation. The existence of URI defers the generation of  VPace by extending the AVI interval to the length of the URI interval.

1.2    Instructions

•    Use UPPAAL to build a DDD mode pacemaker to deliver treatments conforming to the timing

constraints (const int AEI = 800; const int AVI = 150; const int VRP = 150; constint PVARP = 100; const int URI = 400; const int LRI = AEI + AVI;).

•    Perform. the verification of the following properties on the closed-loop system, composed of the heart model, the DDD mode pacemaker and monitors.

1.     The system is deadlock free.

2.    A ventricular sense (VS) cannot be generated within VRP.

3. An atrial sense (AS) cannot be generated within PVARP.

4.     The pacemaker never delivers a pacing pulse (AP) within AEI.

5.     The pacemaker never delivers a pacing pulse (VP) within AVI.

6.     The pacemaker never delivers a pacing pulse (VP) within URI.

7.     The time interval between two consecutive ventricular events is always lessor equal to LRI.

8. The pacemaker can  deliver a pacing pulse  (VP), where the  time interval between this  VP and its preceding atrial event is greater than AVI.

1.3    Marking Criteria (Weighting)

•    Modeling                                                                                     60%

o Use clocks to model the timing constraints.          60%

•    Verification                                                                                40%

o Modeling and verification of each property.         8×5%

2   References

[1]  Zhao,  Yu,  and  Partha  S.  Roop.  "Model-Driven  Design  of  Cardiac  Pacemaker  Using  IEC  61499 Function   Blocks." Distributed   Control   Applications:   Guidelines, Design Patterns, and   Application Examples with the IEC 61499 9 (2016): 335.

[2] Jiang, Z., Pajic, M., Moarref, S., Alur, R., & Mangharam, R. (2012, March). Modeling and verification of a dual chamber implantable pacemaker. In International Conference on Tools and Algorithms for the

Construction and Analysis of Systems(pp. 188-203). Springer, Berlin, Heidelberg.