Problem

The Problem entity represents a Vehicle Routing Problem. It consists of two main parts: plan and fleet.

Plan

A plan contains a list of jobs to be served, and optionally a list of relations between these jobs and vehicles.

Job

Essentially, this entity represents a job to be served by any vehicle taking into account specific properties:

  • location (required): location represented via latitude and longitude:

    "location": {"lat": 52.5622847, "lng": 13.4023099}

  • duration (required): duration in seconds (service time): a time spent at a given location:

    "duration": 120

  • demand (required): demand represented via multidimensional units of measure, e.g. volume, mass, size, etc:

    "demand": [1]

  • times (optional): a list of time windows specifying when the vehicle is allowed to visit the given location. Date is represented in RFC3339 format:

    "times": [["2020-07-04T06:00:05.000Z","2020-07-04T12:05:05.000Z"]]

  • skills (optional): a list of skills which should be defined on the vehicle type serving the job.

    "skills": ["fridge"]

  • tag (optional): a user defined tag associated within a given place. It is propagated back within the solution.

    "tag": "pickup_1"

Note: Avoid referencing any confidential or personal information as part of the tag.

Depending on how the places property is specified, a job can be one of three types:

  • pickup: a job for picking something along the route and bringing it to route's end location. It is used when only the pickups place with one job place is specified. An example of a pickup job:
{
        "id": "pickup1",
        "places": {
          "pickups": [
            {
              "location": {"lat": 52.5622847, "lng": 13.4023099},
              "duration": 180,
              "demand": [1]
            }
          ]
        }
      }
  • delivery: a job for delivering something loaded at the beginning of the route. It is used when only the deliveries place with one job place is specified. An example of a delivery job:
{
        "id": "delivery1",
        "places": {
          "deliveries": [
            {
              "location": {"lat": 52.5252832, "lng": 13.41884},
              "duration": 180,
              "demand": [1]
            }
          ]
        }
      }
  • pickup and delivery job: a job for picking and delivering along the route. It is used when both pickups and deliveries places are specified. The job can have multiple pickups and deliveries. All or none of them have to be served. Also the sum of demands for pickup and delivery places should be equal. A basic scenario for it could be multiple pickups at different places followed by a single delivery. An example of a job with multiple job places:
{
        "id": "myMultiJob",
        "places": {
          "pickups": [
            {
              "location": {"lat": 52.5622847, "lng": 13.4023099},
              "duration": 180,
              "demand": [1],
              "tag": "p1"
            },
            {
              "location": {"lat": 52.5330881, "lng": 13.3973059},
              "duration": 180,
              "demand": [1],
              "tag": "p2"
            }
          ],
          "deliveries": [
            {
              "location": {"lat": 52.5252832, "lng": 13.41884},
              "duration": 180,
              "demand": [2],
              "tag": "d1"
            }
          ]
        }
      }

Limit on the number of jobs

The total amount of jobs is calculated as the sum of all pickups and deliveries included in jobs.

Relation

Using the optional relations parameter, we can define various relations between jobs and vehicles.

There are three types of relations specified by type:

  • sequence: the order of the jobs which are specified in this relation may not be changed and must be served by this particular vehicle. No additional job may be inserted between those jobs that are specified in this relation
  • flexible: the jobs that are specified in this relation must be served by this particular vehicle. The order among the jobs defined in this relation may not be changed. Jobs that are not specified in this or another relation can be inserted anywhere in this vehicle's tour even between the jobs defined in this relation
  • tour: the jobs that are specified in this relation must be served by this particular vehicle. The order of the jobs specified in this relation may be changed.

With the jobs property, each relation specifies a list of activities performed by a specific vehicle. There are four possible job types:

  • jobId: regular job id. (Note: Avoid referencing any confidential or personal information as part of the jobId.)
  • departure: departure activity
  • arrival: arrival activity
  • break: vehicle break activity

The vehicleId property is used to stick jobs to the specific vehicle with the given id. Check the next section for details about the vehicle id.

By using relations for our vehicles and jobs, we can influence the behavior of the algorithm for the re-planning process, and it's result.

{
  "relations": [
    {
      "type": "sequence",
      "jobs": ["departure", "job1", "job2"],
      "vehicleId": "1_1"
    }
  ]
}

Please note that jobs added into a sequence or a flexible relation are not checked for any constraint violations, e.g. time windows, skill requirements, capacity violations, pickup/delivery assignment, routing availability, etc. This might lead to infeasible or undesired solutions. Also a relation cannot be used with a job with multiple pickups or deliveries.

Fleet

A fleet specifies a list of vehicle types and their routing profiles.

VehicleType

Each vehicle type is defined by the following properties:

  • id: a unique identifier of a vehicle type. In the solution, it is used to generate specific vehicle ids using the pattern ${vehicleType}_${sequence_index}.

    "id": "vehicle"

Note: Avoid referencing any confidential or personal information as part of the vehicle's Id.

  • profile: specifies the name of the routing profile (see next section)

    "profile": "normal_car"

Note: Avoid assigning real-life identifiers, such as for instance a vehicle license plate id as the profileName of the routing profile.

  • costs: defines different vehicle costs:
    • fixed cost to start using the vehicle
    • distance cost per meter
    • time cost per second
  {
    "costs": {
      "distance": 0.0002,
      "time": 0.004806,
      "fixed": 22
    }
  }
  • shifts: specifies an array of depot places where vehicles of this particular type should start and end:

    {
      "shifts": [{
        "start": {
          "time": "2020-07-04T09:00:00Z",
          "location": {"lat": 52.46642, "lng": 13.28124}
        },
        "end": {
          "time": "2020-07-04T18:00:00Z",
          "location": [52.46642, 13.28124]
        },
        "breaks": [
          {
           "times": [["2020-07-04T06:00:05.000Z","2020-07-04T12:05:05.000Z"]],
           "location": {"lat": 52.46642, "lng": 13.28124},
           "duration": 3600
          }
        ]
      }]
    }
    

    Each place is specified by time and location. Start time means earliest departure time, end time latest arrival time. The optional parameter breaks specifies a list of vehicle breaks during the tour (at the moment, not more than one). A Break has an optional location property, if it is omitted then the vehicle takes it's break at the last served job's location.

    The end location is optional: if it is omitted then vehicle's route ends at the last job location.

  • capacity: vehicle capacity represented via multidimensional units of measure, e.g. volume, mass, size, etc:

    "capacity": [10]

  • skills: a list of vehicle skills which can be used to serve jobs

    "skills": ["fridge"]

  • limits: specifies constraints applied to a vehicle type

    • maxDistance: specifies the maximum distance limitation for our vehicle in meters
    • shiftTime: defines the shift time for the vehicle in seconds
{
  "limits": {
    "maxDistance": 30000,
    "shiftTime": 28800
  }
}

Routing Profile

Different routing profiles are specified as elements in the profiles collection. There are two possible profile types: car and truck. They have the following common properties:

  • name: a unique name of the routing profile. It is used on the vehicle type definition "name": "normal_car"

  • type: specifies the routing profile type, possible values: car, truck

    "profile": "car"

  • departureTime: specifies a vehicle's departure time. If omitted, the earliest shift start time of all vehicle types sharing the same vehicle profile is used.

  • avoid: specifies a list of routing features that should be avoided

Car Profile

At the moment, the car profile does not have any extra properties.

Truck Profile

Truck limitations are defined using the truckOptions field in the problem request.

The shippedHazardousGoods option sets a list of hazardous materials shipped by the trucks, such as explosives, gas and materials harmful to water. For the full list of options, see the API Reference.

Other options describe the physical attributes of the truck: weight limit, weight per axle, height, width and length. The tunnel category option restricts the routes to pass only through tunnels of a less strict category.

Example

An example of a Problem:

{
  "plan": {
    "jobs": [
      {
        "id": "myJob",
        "places": {
          "deliveries": [
            {
              "location": {"lat": 52.46642, "lng": 13.28124},
              "times": [["2020-07-04T10:00:00.000Z","2020-07-04T12:00:00.000Z"]],
              "duration": 180,
              "demand": [1]
            }
          ]
        }
      }
    ]
  },
  "fleet": {
    "types": [
      {
        "id": "myVehicle",
        "profile": "normal_car",
        "costs": {
          "distance": 0.0002,
          "time": 0.005,
          "fixed": 22
        },
        "shifts": [{
          "start": {
            "time": "2020-07-04T09:00:00Z",
            "location": {"lat": 52.52568, "lng": 13.45345}
          },
          "end": {
            "time": "2020-07-04T18:00:00Z",
            "location": {"lat": 52.52568, "lng": 13.45345}
          }
        }],
        "limits": {
          "maxDistance": 300000,
          "shiftTime": 28800
        },
        "capacity": [10],
        "amount": 1
      }
    ],
    "profiles": [{
      "name": "normal_car",
      "type": "car",
      "departureTime": "2020-07-04T09:15:00Z"
    }]
  }
}

results matching ""

    No results matching ""