CAPS RoutePro

1. CAPS RoutePro • Routing Environment. • Solution Methods. • Backhauls. • Dispatcher Interface. • Demonstration.

2. Routing Environment • Load and unload times. • Compatibility rules. • Routing Properties. • Routing Methods.

3. 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)

4. Load and Unload Times

5. 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.

6. Driver and Vehicle Compatibility

7. Vehicle and Product Compatibility

8. 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.

9. Enforcements

10. Travel Properties Adjust straight line distance for circuity. For multiple stops at same location.

11. a b Travel a-b direct or along blue access roads? Access to Road Network • Sites are not on the road network. • Use “access roads” to nearest intersection (node). • Can specify speed and circuity.

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

13. if a + b + d + e <= x + 200 d e x Out-of-Route Travel Add the new stop if it is not too far out of route 2nd New stop b a 3rd c 1st last

14. 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.

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

16. b c a d g e f Route must satisfy: c+g <= 0.15(a+b+c+d+e+f+g) Deadhead Travel Dashed lines indicate deadhead travel P = Pickup D = Delivery D1 P3 D2 P1,P2 P4 x D3 D4

17. Order Priorities Distance from depot, Quantity, or Time window

18. 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.

19. RoutePro Solution Techniques • Nearest Neighbor. • Nearest Pass. • Pie Algorithm. • Boundary Algorithm. • Cluster Algorithm. • Savings Algorithm. • Tree Algorithm. • Weighted Constraint Algorithm. • Add to Existing Algorithm.

20. 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.

21. Route Limits Prevents adding orders far from route.

22. 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.

23. 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

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

25. Nearest Neighbor

26. 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.

27. Nearest Pass Limit candidate orders to within yellow region or within 1 mile of depot.

28. 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?

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

30. 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.

31. Boundary Algorithm Repeats Pie Algorithm for larger and larger slices.

32. 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.

33. 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.

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

35. 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.

36. Tree Algorithm

37. b a d c Add Order 1 to route since a+b < c+d Tree Algorithm Should order 1 or 2 be added next? Order 1 Seed Order 2

38. 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.

39. 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.

40. Route Improvement Algorithms • After building initial routes. • Resequence stops on a route (intra-route improvements). • Manually move stops or add stops.

41. Empty Return Backhaul Backhauls Compare profit from deadheading and carrying a backhaul. Pickup Delivery depot D D

42. 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.

43. 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.

44. 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

45. Zoomed In View 5 Hardware stores 4 Locksmiths

46. Nearest Neighbor vs. Nearest Pass 16 routes, $10,254 11 routes, $9,795

47. Pie Algorithm vs. Boundary Algorithm 16 routes, $9,587 13 routes, $9,122

48. Cluster Algorithm vs. Savings Alg. 21 routes, $8,650 - 108 orders 20 routes, $16,583

49. Tree Algorithm vs. Weighted Constraint 11 routes, $8,600 12 routes, $9,962

50. Route Summary