HPC module

METS-R HPC is used to control multiple simulation instances that can run and exchange data through WebSocket connects. Apache Kafka is used to explicitly model the data stream. The overall HPC framework is shown in the figure below, note this framework allows us to separate the logics of modeling data processing, decision generation, traffic simulation, and potentially cyber attacks.

HPC framework

HPC framework

Code structure

Four types of classes are used:

  • Client for interfacing the data communication between simulators and other components.

  • Runner for defining different types of experiments.

  • Model for implementing operational algorithms.

  • Config for storing the configuration templates.

Besides these, we provide the example scripts: interactive_example.ipynb, cosim_example.py.

Interactive APIs

The following APIs are implemented to interact with the METS-R SIM, here sim_client is an instance of METSRClient.

STEP

Name

Description

Examples

Return

tick

Move the simulation one tick forward

sim_client.tick()

QUERY

If an agent ID is provided, a query would return the information of the specific agent, otherwise, it will return a list containing the ID of all agents.

Name

Description

Examples

Return

query_vehicle(id=None, private_veh=False, transform_coords=False)

Get the information of one or more vehicles. By default, queries public vehicles. Set private_veh=True for private vehicles and transform_coords=True to convert coordinates to SUMO format.

sim_client.query_vehicle(1, True, True)

x, y, speed, acceleration, bearing, origin zone, destination zone, vehicle state

query_taxi(id=None)

Get the information of one or more EV taxis.

sim_client.query_taxi(36879)

x, y, passenger number, vehicle state, origin zone, destination zone

query_bus(id=None)

Get the information of one or more EV buses.

sim_client.query_bus(37732)

battery state, route ID, current stop, passenger number

query_road(id=None)

Get the information of one or more roads.

sim_client.query_road(100011)

speed limit, number of on-road vehicles, average travel time, road length (m), energy consumed, road type

query_centerline(id, lane_index=0, transform_coords=False)

Get the centerline geometry of a specific lane on a road. Set transform_coords=True to return coordinates in SUMO format.

sim_client.query_centerline(100011, 0)

list of (x, y) coordinate pairs along the lane centerline

query_zone(id=None)

Get the information of one or more demand zones.

sim_client.query_zone(0)

vehicle stock, taxi demand, bus demand, x, y, zone type

query_signal(id=None)

Get the information of one or more traffic signals.

sim_client.query_signal(14)

current phase, next phase, next update time

query_signal_group(id)

Get the signal group information for a given signal controller ID, including all phases and their durations.

sim_client.query_signal_group(14)

signal group ID, phase list, phase durations

query_signal_between_roads(upstream_road, downstream_road)

Query the signal controlling the connection between two consecutive roads.

sim_client.query_signal_between_roads("r1", "r2")

signal ID, current phase, next update time

query_chargingStation(id=None)

Get the information of one or more EV charging stations.

sim_client.query_chargingStation(-10)

x, y, number of available chargers

query_coSimVehicle()

Get the vehicle IDs currently located on the co-simulation road.

sim_client.query_coSimVehicle()

list of vehicle IDs on the co-sim road

query_route(orig_x, orig_y, dest_x, dest_y, transform_coords=False)

Query the shortest route between two coordinate-specified locations. Set transform_coords=True if inputs are in SUMO coordinate format.

sim_client.query_route(10.0, 20.0, 50.0, 80.0)

ordered list of road IDs forming the route

query_route_between_roads(orig_road, dest_road)

Query the shortest route between two road IDs.

sim_client.query_route_between_roads("r1", "r2")

ordered list of road IDs forming the route

query_road_weights(roadID=None)

Query the current edge weights (travel time or energy cost) used for routing. Returns weights for all roads if no ID is specified.

sim_client.query_road_weights(100011)

road ID, current weight value

query_bus_route(routeID)

Get the stop sequence and road path for a named bus route.

sim_client.query_bus_route("route_1")

route name, stop zone IDs, road path

query_route_bus(routeID)

Get all active buses currently assigned to a specific route.

sim_client.query_route_bus("route_1")

list of bus IDs on the route

CONTROL

Name

Description

Examples

Inputs

generate_trip(vehID, origin=-1, destination=-1)

Generate a vehicle trip between origin and destination zones.

sim_client.generate_trip("veh_1", 3, 5)

vehID, origin zone ID, destination zone ID

generate_trip_between_roads(vehID, origin, destination)

Generate a vehicle trip between origin and destination roads.

sim_client.generate_trip_between_roads("veh_1", "r1", "r2")

vehID, origin road ID, destination road ID

set_cosim_road(roadID)

Set one or more roads for co-simulation. Vehicles on these roads will be controlled externally.

sim_client.set_cosim_road("road_2")

roadID

release_cosim_road(roadID)

Release one or more co-simulation roads, returning vehicle control to the simulator.

sim_client.release_cosim_road("road_2")

roadID

teleport_cosim_vehicle(vehID, x, y, bearing, private_veh=False, transform_coords=False)

Teleport a co-simulation vehicle to a specified coordinate with a given heading. Set transform_coords=True if coordinates are in SUMO format.

sim_client.teleport_cosim_vehicle("veh_1", 10.5, 25.0, 90.0)

vehID, x, y, bearing (degrees), private_veh, transform_coords

teleport_trace_replay_vehicle(vehID, roadID, laneID, dist, private_veh=False)

Teleport a vehicle to a position specified by road ID, lane index, and distance from the downstream junction.

sim_client.teleport_trace_replay_vehicle("veh_1", "road_3", 1, 30.0)

vehID, roadID, laneID, dist, private_veh

enter_next_road(vehID, private_veh=False)

Move a co-simulation vehicle onto the next road in its planned route.

sim_client.enter_next_road("veh_1")

vehID, private_veh

reach_dest(vehID, private_veh=False)

Signal that a co-simulation vehicle has reached its destination and should be removed from the network.

sim_client.reach_dest("veh_1")

vehID, private_veh

control_vehicle(vehID, acc, private_veh=False)

Directly override the acceleration of a vehicle for the current tick.

sim_client.control_vehicle("veh_1", 2.5)

vehID, acc (m/s²), private_veh

update_vehicle_sensor_type(vehID, sensorType, private_veh=False)

Change the sensor type of a vehicle (e.g., for V2X data stream configuration).

sim_client.update_vehicle_sensor_type("veh_1", "LiDAR")

vehID, sensorType, private_veh

update_vehicle_route(vehID, route, private_veh=False)

Override the planned route of a vehicle with a new ordered list of road IDs.

sim_client.update_vehicle_route("veh_1", ["r1", "r2", "r3"])

vehID, route (list of road IDs), private_veh

dispatch_taxi(vehID, orig, dest, num)

Dispatch a specific taxi to serve a passenger request between two zones.

sim_client.dispatch_taxi("taxi_1", 0, 2, 1)

vehID, origin zone ID, destination zone ID, num passengers

dispatch_taxi_between_roads(vehID, orig, dest, num)

Dispatch a specific taxi to serve a request between two road-specified locations.

sim_client.dispatch_taxi_between_roads("taxi_1", "r1", "r2", 1)

vehID, origin road ID, destination road ID, num passengers

add_taxi_requests(zoneID, dest, num)

Inject a taxi passenger request at a zone, to be fulfilled by the simulator’s dispatch logic.

sim_client.add_taxi_requests(1, 3, 2)

origin zone ID, destination zone ID, num passengers

add_taxi_requests_between_roads(orig, dest, num)

Inject a road-based taxi request from one road to another.

sim_client.add_taxi_requests_between_roads("r1", "r2", 1)

origin road ID, destination road ID, num passengers

assign_request_to_bus(vehID, orig, dest, num)

Assign a passenger request directly to a specific bus.

sim_client.assign_request_to_bus("bus_1", 0, 5, 10)

vehID, origin zone ID, destination zone ID, num passengers

add_bus_requests(zoneID, dest, routeName, num)

Inject a bus passenger request at a zone for a specific route.

sim_client.add_bus_requests(2, 5, "route_1", 15)

origin zone ID, destination zone ID, route name, num passengers

add_bus_route(routeName, zone, road, paths=None)

Define a new bus route by specifying its stop zones and road path. If paths is provided, explicit road paths between stops are used.

sim_client.add_bus_route("route_new", [0,1,2], ["r_a","r_b","r_c"])

route name, list of zone IDs, list of road IDs, optional paths

add_bus_run(routeName, departTime)

Schedule a new bus departure on an existing route at a specified simulation time (in ticks).

sim_client.add_bus_run("route_1", 3600)

route name, departure time (ticks)

insert_bus_stop(busID, routeName, zoneID, roadName, stopIndex)

Dynamically insert a new stop into an active bus route at a given index.

sim_client.insert_bus_stop("bus_1", "route_1", 3, "r_c", 2)

bus ID, route name, zone ID, road name, stop index

remove_bus_stop(busID, routeName, stopIndex)

Remove a stop from an active bus route at a given index.

sim_client.remove_bus_stop("bus_1", "route_1", 2)

bus ID, route name, stop index

update_road_weights(roadID, weight)

Update the routing weight (e.g., travel time or energy cost) for a road segment.

sim_client.update_road_weights(100011, 45.0)

roadID, new weight value

update_charging_prices(stationID, stationType, price)

Update the per-kWh charging price at a specific station. stationType specifies L2 or L3 charger.

sim_client.update_charging_prices(-10, "L3", 0.25)

station ID, charger type, price ($/kWh)

update_signal(signalID, targetPhase, phaseTime)

Force a traffic signal to switch to a target phase, lasting the specified duration (in ticks).

sim_client.update_signal(14, 2, 30)

signal ID, target phase index, phase duration (ticks)

update_signal_timing(signalID, greenTime, yellowTime, redTime)

Update the fixed-time cycle durations (in ticks) of a traffic signal.

sim_client.update_signal_timing(14, 30, 5, 25)

signal ID, green ticks, yellow ticks, red ticks

set_signal_phase_plan(signalID, greenTime, yellowTime, redTime, startPhase, phaseOffset)

Set a complete signal phase plan using durations in seconds.

sim_client.set_signal_phase_plan(14, 30.0, 5.0, 25.0, 0, 0.0)

signal ID, green time (s), yellow time (s), red time (s), start phase, phase offset (s)

set_signal_phase_plan_ticks(signalID, greenTicks, yellowTicks, redTicks, startPhase, tickOffset)

Set a complete signal phase plan using durations in simulation ticks.

sim_client.set_signal_phase_plan_ticks(14, 60, 10, 50, 0, 0)

signal ID, green ticks, yellow ticks, red ticks, start phase, tick offset

save(filename)

Save a full snapshot of the current simulation state to a file, enabling reproducible replay.

sim_client.save("snapshot_t1000.bin")

filename

load(filename)

Restore the simulation to a previously saved state.

sim_client.load("snapshot_t1000.bin")

filename

reset()

Reset the simulation to its initial state using the current configuration.

sim_client.reset()

terminate()

Fully terminate the simulation process.

sim_client.terminate()

close()

Close the client connection while leaving the simulation running.

sim_client.close()