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					CAPS RoutePro

• Routing Environment.

• Solution Methods.

• Backhauls.

• Dispatcher Interface.

• Demonstration.
Routing Environment

• Load and unload times.

• Compatibility rules.

• Routing Properties.

• Routing Methods.
Load and Unload Times

• Fixed time per stop.
  – Minimum time to service a stop.


• Fixed load/unload time.
  – Independent of what and how much is being
    loaded/unloaded.

• Variable load/unload time.
  – In addition to fixed load/unload time.
  – Based on amount being loaded/unloaded.
  – Can round values to reflect partial loads (time to
    move a pallet is same whether full or half full)
Load and Unload Times
Compatibility (Mateability)

• Define compatibility/incompatibility for:
  – Site and vehicle.
   – Work zone and driver or vehicle.
   – Vehicle and order or product.
   – Vehicle and driver.
   – Vehicle and tractor.
   – Product and product.
Driver and Vehicle Compatibility
Vehicle and Product Compatibility
Route Properties

• Which rules to enforce.
  – Capacities.
  – Time windows.
  – Compatibilities.

• Travel Properties.
  – Straight line distance or road network.
  – Access from sites to road network.
  – Out-of-route travel limits.
Enforcements
Travel Properties




                    Adjust straight
                    line distance
                    for circuity.


                    For multiple
                    stops at same
                    location.
 Access to Road Network

• Sites are not on the road network.
• Use “access roads” to nearest intersection
  (node).
• Can specify speed and circuity.




                                        a              b


                              Travel a-b direct or along blue
                              access roads?
Out-of-Route Travel



                      Consider new
                      orders only
                      where out-
                      of-route
                      travel is
                      <200 miles.
Out-of-Route Travel

            Add the new stop if it is not too far out of route

                      if a + b + d + e <= x + 200



           2nd                         New stop
                 b              d
       a             3rd
                                                  e
                                      c
 1st
                           x

                                                      last
More Route Properties

• Deadhead miles.
   – For long-haul travel.
   – Limit empty miles as:
        • % of route distance.
        • Maximum number of empty miles.
        • Maximum number of empty hours.


• Order Priorities.
   –   Farthest from depot.
   –   Largest quantity.
   –   Shortest time window.
   –   Earliest time window.
Deadhead Travel



                  Limit empty
                  miles to 15%
                  of total
                  distance.
Deadhead Travel

                          Dashed lines indicate deadhead travel
                                                    P = Pickup
                                                    D = Delivery
                D1                        P3
                     b             c
        a                 D2                        d
P1,P2


            g                                              P4

                                                e
                     D3        f   x
                                   D4


   Route must satisfy: c+g <= 0.15(a+b+c+d+e+f+g)
Order Priorities




                   Distance from depot,
                   Quantity, or
                   Time window
Routing Methods

• Grow routes.
  – Construct new routes.
  – Add orders to existing routes only.
  – Add orders to existing routes first; then
    construct new routes.

• Resequence stops on a route.
  – Do not move stops between routes.

• Use predefined routes.
  – Provides a baseline for existing routes.
RoutePro Solution Techniques

•   Nearest Neighbor.
•   Nearest Pass.
•   Pie Algorithm.
•   Boundary Algorithm.
•   Cluster Algorithm.
•   Savings Algorithm.
•   Tree Algorithm.

• Weighted Constraint Algorithm.
• Add to Existing Algorithm.
Solution Techniques

• Consider high priority orders first.

• Use route limits to consider only orders that
  do not increase length and cost “too much”.
   – Limit on added miles.
   – Limit on added hours.
   – Limit on added cost.
Route Limits


               Prevents
               adding
               orders far
               from route.
Solution Techniques

• Build routes one order at a time.

• Location of first order placed on a route is
  called the seed.

• Link connecting depot and seed is called the
  skeleton.
   – Many algorithms try to add orders close to the
     skeleton.


• Most methods require user specified angles
  to define potential orders to add.
Nearest Neighbor

• Add nearest order in the specified
  neighborhood to route if feasible.
  –   Highest priority order is seed.
  –   Neighborhood specified by distance and angle.
  –   Only look within specified distance.
  –   Consider small angles first, then expand.




                                                      Seed
Nearest Neighbor




                   Limit candidate
                   orders to within
                   50 miles of
                   seed.
Nearest Neighbor
Nearest Pass

• Add order with least incremental cost to an
  existing route.

• Start new routes if no existing route can
  take a new order.
  – Highest priority order is seed.


• Consider orders only in region around depot
  with specified angle.
Nearest Pass




               Limit candidate
               orders to within
               yellow region or
               within 1 mile of
               depot.
Pie Algorithm

• Add order with smallest angle from skeleton
  within a specified “pie”-shaped region
  centered at depot.
   – Highest priority order is seed.


• Consider orders only in pie-shaped region
  with specified angle - or orders close to the
  depot.

• Solution quality depends on angle specified.
   – What angle is best?
Pie Algorithm




                Limit candidate
                orders to within
                yellow region or
                within 20 miles
                of depot.
Boundary Algorithm

• Multiple use of Pie Algorithm with a user
  specified set of angles to increase size of
  “slice”.

• Specify
   – Minimum angle.
   – Maximum angle.
   – Number of increments.


• Good to find best angle for Pie Algorithm.

• Good for sparse distributions of orders.
Boundary Algorithm




                     Repeats Pie
                     Algorithm for
                     larger and larger
                     slices.
Cluster Algorithm

• Adds orders sequentially for sites close
  together.

• New orders must be within a user specified
  distance of the route and not too near the
  depot.

• Good if orders are clustered in space and
  time.

• Not too good if clustering is not apparent.
Savings Algorithm

• Add orders to routes based on greatest
  “savings”.

• Savings reflect cost to link two orders on a
  route.

• Consider orders only in region of specified
  angle around depot.
Savings Algorithm




                    Limit candidate
                    orders to within
                    yellow region or
                    within 1 mile of
                    depot.
Tree Algorithm

• Adds orders to routes sequentially to
  minimize a weighted sum of two distances
  – from order to seed location.
  – from order to depot.


• User specifies weight to control emphasis on
  distance to depot or to seed for route.

• Useful to minimize empty travel on first and
  last legs of route.
Tree Algorithm
Tree Algorithm

Should order 1 or 2 be added next?

                         Order 1
                               b
            a
                                     Seed

                                      d

                     c
                                          Order 2


      Add Order 1 to route since a+b < c+d
Weighted Constraint Algorithm

• Adds orders to existing routes to minimize
  distance.
   – Does not build new routes.


• Does not require user specified angles.

• Useful for orders that are hard to route.
Add to Existing Algorithm

• Adds orders to existing routes based on
  “regret”.
  – Does not build new routes.


• Regret = difference between cost with order
  on best and second best route.

• Assigns order with highest regret to best
  route.
Route Improvement Algorithms

• After building initial routes.

• Resequence stops on a route (intra-route
  improvements).

• Manually move stops or add stops.
    Backhauls

    Compare profit from deadheading and carrying a
    backhaul.


     Pickup
     Delivery




                depot

                           Empty Return


D                                                    D
                Backhaul
Profitable Backhauler Algorithm

• Requires revenue for potential backhauls to
  be given.

• Considers adding potential backhauls to
  existing routes:
  – Compares net profit for backhaul (revenue - cost)
    with cost to deadhead.
  – Inserts backhaul with largest net profit.
Dispatcher’s Process

• Import orders and validate.

• Select orders to route.

• Build routes.
   – Build new routes and edit routes.
   – Use one or more route methods.
   – Limited to methods allowed by Administrator.


• Analyze results.

• Export routes.
 Demo: New England Acme Tools

• 1 Warehouse

• 425 Customers
  – Hardware stores.
  – Locksmith shops.


• 2 Vehicle Types
  – 48 ft. trailers (25)
  – 28 ft. trailers (15)

• 130 Orders
Zoomed In View

                 5 Hardware stores
                 4 Locksmiths
 Nearest Neighbor vs. Nearest Pass
16 routes, $10,254     11 routes, $9,795
 Pie Algorithm vs. Boundary Algorithm
16 routes, $9,587      13 routes, $9,122
 Cluster Algorithm vs. Savings Alg.
21 routes, $8,650 - 108 orders   20 routes, $16,583
Tree Algorithm vs. Weighted Constraint
11 routes, $8,600      12 routes, $9,962
Route Summary
Cost and Distance
Time Usage
Excel Vehicle Utilization Chart

                                                          Vehicle Utilization Chart
 Max vs. Used Capacity




                         6000
                         5000
                         4000                                                                                                     PEAKQTY1
                         3000
                         2000                                                                                                     MAXCAPACITY1
                         1000
                            0
                                DRLG1




                                                                                               DRSH1
                                        DRLG10
                                                 DRLG11
                                                           DRLG12
                                                                    DRLG13
                                                                             DRLG14
                                                                                      DRLG15


                                                                                                       DRSH10
                                                                                                                DRSH11
                                                                                                                         DRSH12
                                                                    Vehicle ID
Excel Vehicle Use Chart

                                    Vehicles Used In Time
 Number of vehicles




                      8
                      6
      used




                      4
                      2
                      0
                      Mar/17   Mar/18   Mar/18    Mar/19      Mar/19   Mar/20   Mar/20
                      12:00     0:00    12:00      0:00       12:00     0:00    12:00
                                                 Route time
RoutePro Summary

• Very powerful package.

• Handles wide range of routing problems and
  real-world complexities.

• Allows user (administrator) control over all
  aspects.

• Provides multiple solution algorithms.
   – Must select best algorithm for each application.

				
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posted:11/26/2012
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