A vehicle's route can be decomposed, along the time axis, like this (we assume there are n visits):
| | | | | T[2], | | |
| Transition | Visit #0 | | | V[2], | | |
| #0 | aka | T[1] | V[1] | ... | V[n-1] | T[n] |
| aka T[0] | V[0] | | | V[n-2],| | |
| | | | | T[n-1] | | |
^ ^ ^ ^ ^ ^ ^ ^
vehicle V[0].start V[0].end V[1]. V[1]. V[n]. V[n]. vehicle
start (arrival) (departure) start end start end end
Note that we make a difference between:
- "punctual events", such as the vehicle start and end and each visit's start and end (aka arrival and departure). They happen at a given second.
- "time intervals", such as the visits themselves, and the transition between visits. Though time intervals can sometimes have zero duration, i.e. start and end at the same second, they often have a positive duration.
Invariants:
- If there are n visits, there are n+1 transitions.
- A visit is always surrounded by a transition before it (same index) and a transition after it (index + 1).
- The vehicle start is always followed by transition #0.
- The vehicle end is always preceded by transition #n.
Zooming in, here is what happens during a Transition
and a Visit
:
---+-------------------------------------+-----------------------------+-->
| TRANSITION[i] | VISIT[i] |
| | |
| * TRAVEL: the vehicle moves from | PERFORM the visit: |
| VISIT[i-1].departure_location to | |
| VISIT[i].arrival_location, which | * Spend some time: |
| takes a given travel duration | the "visit duration". |
| and distance | |
| | * Load or unload |
| * BREAKS: the driver may have | some quantities from the |
| breaks (e.g. lunch break). | vehicle: the "demand". |
| | |
| * WAIT: the driver/vehicle does | |
| nothing. This can happen for | |
| many reasons, for example when | |
| the vehicle reaches the next | |
| event's destination before the | |
| start of its time window | |
| | |
| * DELAY: *right before* the next | |
| arrival. E.g. the vehicle and/or | |
| driver spends time unloading. | |
| | |
---+-------------------------------------+-----------------------------+-->
^ ^ ^
V[i-1].end V[i].start V[i].end
Lastly, here is how the TRAVEL, BREAKS, DELAY and WAIT can be arranged during a transition.
- They don't overlap.
- The DELAY is unique and must be a contiguous period of time right before the next visit (or vehicle end). Thus, it suffice to know the delay duration to know its start and end time.
- The BREAKS are contiguous, non-overlapping periods of time. The response specifies the start time and duration of each break.
- TRAVEL and WAIT are "preemptable": they can be interrupted several times during this transition. Clients can assume that travel happens "as soon as possible" and that "wait" fills the remaining time.
A (complex) example:
TRANSITION[i]
--++-----+-----------------------------------------------------------++-->
|| | | | | | | ||
|| T | B | T | | B | | D ||
|| r | r | r | W | r | W | e ||
|| a | e | a | a | e | a | l ||
|| v | a | v | i | a | i | a ||
|| e | k | e | t | k | t | y ||
|| l | | l | | | | ||
|| | | | | | | ||
--++-----------------------------------------------------------------++-->
JSON representation |
---|
{ "vehicleIndex": integer, "vehicleLabel": string, "vehicleStartTime": string, "vehicleEndTime": string, "visits": [ { object ( |
Fields | |
---|---|
vehicle |
Vehicle performing the route, identified by its index in the source |
vehicle |
Label of the vehicle performing this route, equal to |
vehicle |
Time at which the vehicle starts its route. A timestamp in RFC3339 UTC "Zulu" format, with nanosecond resolution and up to nine fractional digits. Examples: |
vehicle |
Time at which the vehicle finishes its route. A timestamp in RFC3339 UTC "Zulu" format, with nanosecond resolution and up to nine fractional digits. Examples: |
visits[] |
Ordered sequence of visits representing a route. visits[i] is the i-th visit in the route. If this field is empty, the vehicle is considered as unused. |
transitions[] |
Ordered list of transitions for the route. |
has |
When
Arrival at next_visit will likely happen later than its current time window due the increased estimate of travel time |
route |
The encoded polyline representation of the route. This field is only populated if |
breaks[] |
Breaks scheduled for the vehicle performing this route. The |
metrics |
Duration, distance and load metrics for this route. The fields of |
route |
Cost of the route, broken down by cost-related request fields. The keys are proto paths, relative to the input OptimizeToursRequest, e.g. "model.shipments.pickups.cost", and the values are the total cost generated by the corresponding cost field, aggregated over the whole route. In other words, costs["model.shipments.pickups.cost"] is the sum of all pickup costs over the route. All costs defined in the model are reported in detail here with the exception of costs related to TransitionAttributes that are only reported in an aggregated way as of 2022/01. |
route |
Total cost of the route. The sum of all costs in the cost map. |
Visit
A visit performed during a route. This visit corresponds to a pickup or a delivery of a Shipment
.
JSON representation |
---|
{
"shipmentIndex": integer,
"isPickup": boolean,
"visitRequestIndex": integer,
"startTime": string,
"loadDemands": {
string: {
object ( |
Fields | |
---|---|
shipment |
Index of the |
is |
If true the visit corresponds to a pickup of a |
visit |
Index of |
start |
Time at which the visit starts. Note that the vehicle may arrive earlier than this at the visit location. Times are consistent with the A timestamp in RFC3339 UTC "Zulu" format, with nanosecond resolution and up to nine fractional digits. Examples: |
load |
Total visit load demand as the sum of the shipment and the visit request |
detour |
Extra detour time due to the shipments visited on the route before the visit and to the potential waiting time induced by time windows. If the visit is a delivery, the detour is computed from the corresponding pickup visit and is equal to:
Otherwise, it is computed from the vehicle
A duration in seconds with up to nine fractional digits, ending with ' |
shipment |
Copy of the corresponding |
visit |
Copy of the corresponding |
Transition
Transition between two events on the route. See the description of ShipmentRoute
.
If the vehicle does not have a startLocation
and/or endLocation
, the corresponding travel metrics are 0.
JSON representation |
---|
{ "travelDuration": string, "travelDistanceMeters": number, "trafficInfoUnavailable": boolean, "delayDuration": string, "breakDuration": string, "waitDuration": string, "totalDuration": string, "startTime": string, "routePolyline": { object ( |
Fields | |
---|---|
travel |
Travel duration during this transition. A duration in seconds with up to nine fractional digits, ending with ' |
travel |
Distance traveled during the transition. |
traffic |
When traffic is requested via |
delay |
Sum of the delay durations applied to this transition. If any, the delay starts exactly A duration in seconds with up to nine fractional digits, ending with ' |
break |
Sum of the duration of the breaks occurring during this transition, if any. Details about each break's start time and duration are stored in A duration in seconds with up to nine fractional digits, ending with ' |
wait |
Time spent waiting during this transition. Wait duration corresponds to idle time and does not include break time. Also note that this wait time may be split into several non-contiguous intervals. A duration in seconds with up to nine fractional digits, ending with ' |
total |
Total duration of the transition, provided for convenience. It is equal to:
A duration in seconds with up to nine fractional digits, ending with ' |
start |
Start time of this transition. A timestamp in RFC3339 UTC "Zulu" format, with nanosecond resolution and up to nine fractional digits. Examples: |
route |
The encoded polyline representation of the route followed during the transition. This field is only populated if |
route |
Output only. An opaque token that can be passed to Navigation SDK to reconstruct the route during navigation, and, in the event of rerouting, honor the original intention when the route was created. Treat this token as an opaque blob. Don't compare its value across requests as its value may change even if the service returns the exact same route. This field is only populated if |
vehicle |
Vehicle loads during this transition, for each type that either appears in this vehicle's The loads during the first transition are the starting loads of the vehicle route. Then, after each visit, the visit's |
EncodedPolyline
The encoded representation of a polyline. More information on polyline encoding can be found here: https://developers.google.com/maps/documentation/utilities/polylinealgorithm https://developers.google.com/maps/documentation/javascript/reference/geometry#encoding.
JSON representation |
---|
{ "points": string } |
Fields | |
---|---|
points |
String representing encoded points of the polyline. |
Break
Data representing the execution of a break.
JSON representation |
---|
{ "startTime": string, "duration": string } |
Fields | |
---|---|
start |
Start time of a break. A timestamp in RFC3339 UTC "Zulu" format, with nanosecond resolution and up to nine fractional digits. Examples: |
duration |
Duration of a break. A duration in seconds with up to nine fractional digits, ending with ' |