April 22, 2023

Vermelding onderdeel organisatie

Transportation simulatorCIM project meeting

CIM Project meeting

Jonne Zutt

April 22, 2023 2

Contents

• Transport Planning• TP Simulator• Pamela• TP Simulator

April 22, 2023 3

Transport Planning - overview

Infrastructure

Agents

Orders

Incidents

(Re)Planning

Execution &monitoring

Statistics Order stateAgent history

TP Simulator

April 22, 2023 4

Incident management

• Any event from outside the planning system that cannot be anticipated with certainty.• new orders, changes in orders• road blocks, traffic jams• malfunctional vehicles

• What is incident management?• Ensuring the correct operation of a system

under the events of incidents• Detection, repair and notification of problems

April 22, 2023 5

Agent plan• Route Rt =n,• Schedule Sd = n, where i is claimed at time i,• (Un)loading U, L = (O)n.

Performance measures• Infrastructure resource utilization, transportation

resource utilization,• Sum of pick-up / delivery penalties,• Scalability: cpu load and communication.

April 22, 2023 6

Transport Planning

• Testing performance and robustness of routing/scheduling algorithms in normal conditions varying order densities / agents / infrastructure properties.

• Testing performance and robustness with different incident rates.

April 22, 2023 7

TP Simulator for CIM

• Similarities:• Communicating agents with different

capabilities• Resource based planning• Blackboard, negotiation, auction, contracting

• Differences:• Claiming multiple resources simultaneously• Tasks with precedence relations [Jeroen]

April 22, 2023 8

Pamela

• A.J.C. van Gemund• General-purpose performance simulation

interface,• Concurrency is obtained by using light-weight

threads,• Based on procedure-oriented (P/V-style)

paradigm,• Fast discrete event simulator.

April 22, 2023 9

Pamela run-time library [tr-1994-03]• Process pam_proc:

• Light-weight thread• Local timestamp

• Semaphore pam_sema:• Credit• Queue of blocked processes

• At each time, only one process is running (preemptive vs. non-preemptive)

• pam_time( ), pam_delay(delay)• pam_P(sema), pam_V(sema), pam_T(sema)

April 22, 2023 10

Pamela – communication

Send(msg)

pam_P(room)push(msg)pam_V(data)

Receive( )

pam_P(data)pop(msg)pam_V(room)

return msg

Non-blocking-receive( )

if pam_T(data) > 0return Receive( )

elsereturn NoMessageAvailable

Msg 1 data.credit = 2room.credit = 4

Msg 2

April 22, 2023 11

Pamela – capacity constraints

Drive(A, B)

pam_P(cap_B)arbitrated_pam_V(cap_A)pam_delay(…)

Arbitrated_pam_V(sema)

pam_V(sema)Reschedule processes that are

blocked for sema

• Each infrastructure resource has acapacity semaphore cap_, with its creditinitialized to the capacity of the resource.

April 22, 2023 12

Visualize agent plans

April 22, 2023 13

Preliminary results