transportation simulator
DESCRIPTION
Transportation simulator. CIM project meeting. CIM Project meeting. Jonne Zutt. Contents. Transport Planning TP Simulator Pamela TP Simulator. Infrastructure. Agents. Orders. Incidents. Transport Planning - overview. TP Simulator. (Re)Planning. Execution & monitoring. - PowerPoint PPT PresentationTRANSCRIPT
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
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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
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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.
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Visualize agent plans
April 22, 2023 13
Preliminary results