routeDurationBalancing / balancing of tour durations

[Bernd Welter]

In Route Optimization Optiflow 1.13.0 we invented a new parameter: vehicle.preferences.routeDurationBalancing:

• Feature: Added a preference for balanced routes on the vehicle configuration. Higher values indicate a stronger preference for route durations close to the the average route duration.

As a user of xTour1 I am familiar with xTour1.BalancingParams and therefore I was expecting a specific behaviour but I just learned that this is not matching 100%. Let me explain this with a sample scenario:

• 100 delivery orders in the area of wider Berlin, each one with a capa of 1
• 1 depot, 10 vehicles, each one with enough space to handle 100% of the orders
• As time constraints apply the optimal solution in the default case is utilizing 8 of the 10 vehicles and the durations of the 8 routes comes along with 5 to 8 hours, so the longest route is 60% longer than the shortest one.

  

  routeDurationBalancing=0 for all vehicles (default)

• The new parameter manages to reorganize the routes to a 6-8 hours result, so the driver who has to serve the longest route works 33% longer than the one with the monimum duration.

  

  routeDurationBalancing=1 for all vehicles (invented in 1.13.0)

• And here comes the difference if you compare this with xTour1:

  

  Additional client constraint: maximum tour duration set to 6:15 enforces utilization of the total fleet.

  • With BalancingParams in use the xTour1 would utilize ALL 10 vehicles and try to find an equal workload for all the drivers.
  • Optiflow determines the number of Vehicles needed and then balance the workload over all the drivers.
  • To simulate this in Optiflow I appllied a maximum tour length of 6:15 hours.
• Be aware that balancing might increase the total costs - this is the price you have to be aware of!

  

  Comparison of the costs of the three plannings.