Introducing slack or wait time into passenger routing problem using VRP

KenBakke — Wed, 20 Oct 2010 11:50:35 GMT

I am trying to schedule transportation for passengers to appointments at a facility. I am having problems controlling the wait time on the resulting route effectively. My test problem consists of 3 passengers located at various locations within 10 minutes of the single facility. One of the passengers has a 7:00 am appointment and the other two have a 10:00 appointment. I constructed the problem with six total orders and three order pairs as follows:

Orders:
Passenger 1 - pickup quanity 1 located within 10 minutes of facility, service time .5
Passenger 2 - pickup quanity 1 located within 10 minutes of facility, service time .5
Passenger 3 - pickup quanity 1 located within 10 minutes of facility, service time .5
Facility 1 - delivery quanity 1, TimeWindowStart1 = 7:00, TimeWindowEnd1 = 7:05, service time .1
Facility 2 - delivery quanity 1, TimeWindowStart1 = 10:00, TimeWindowEnd1 = 10:05, service time .1
Facility 3 - delivery quanity 1, TimeWindowStart1 = 10:00, TimeWindowEnd1 = 10:05, service time .1

Order Pairs:
Passenger 1,Facility 1, MaxTransitTime = 60
Passenger 2,Facility 2, MaxTransitTime = 60
Passenger 3,Facility 3, MaxTransitTime = 60

I have also included a depot and a single route.

When I solve this problem, Passenger 1 and Facility 1 are unassigned. The route created is:
Passenger 2 - Arrive at: 9:46
Passenger 3 - Arrive at 9:56
Facility 2 - Arrive at 10:04
Facility 3 - Arrive at 10:05

If I increase the MaxTransitTime in the order pairs to 240, the problem will solve with the resulting solution:

Passenger 1 - Arrive at: 6:51 - Depart at 6:51
Facility 1 - Arrive at 7:05 - Depart at 7:05
Passenger 2 - Arrive at 7:16 - Depart at 7:17
Passenger 3 - Arrive at 7:27 - Depart at 7:27
Facility 2 - Arrive at 7:35 - Depart at 10:00 - Wait time 145
Facility 3 - Arrive at 10:00 - Depart at 10:00

I need to control the location of the wait time. It is obvious that my original set of constraints can easily be met if there is a mechanism to ask the vehicle to wait between Facility 1 and Passenger 2. How can I accomplish this? Am I missing some type of configuration that allows slack or wait time?

Re: Introducing slack or wait time into passenger routing problem using VRP

NaAn — Thu, 21 Oct 2010 16:28:11 GMT

Hi,

You need to add the pickup time window to avoid the wait time between Facility 2 and Facility 3. VRP solver will only apply the wait time in front of the orders with time windows. You may try to add the pickup time window for passenger 2 and 3 (i.e. [9am, 10am]) and see whether the solution meets your expectation.

Please let me know if you have more questions.

Thanks.

Anna

Re: Introducing slack or wait time into passenger routing problem using VRP

KenBakke — Fri, 22 Oct 2010 09:54:32 GMT

Thank you Anna, your solution worked well for me.

topic Re: Introducing slack or wait time into passenger routing problem using VRP in ArcGIS Network Analyst Questions

Introducing slack or wait time into passenger routing problem using VRP

Re: Introducing slack or wait time into passenger routing problem using VRP

Re: Introducing slack or wait time into passenger routing problem using VRP