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Bridge Client

The bridge client gets information about the simulation world, actors and the ego vehicle from the Carla simulation server. It also receives the control commands as supplied by the ADS (Automated Driving System) and applies it to the simulated ego vehicle.

The bridge client consists of two files, bridgeClient.py and apolloEncode.py. The former handles communication with the bridge server and the latter handles encoding of messages into formats compatible with the Baidu Apollo ADS.

bridgeClient.py

src.sim.bridgeClient.ApolloBridgeClient_ActorGTPublisher(hostIP, hostPort)

Bases: BridgeClient

Generic Bridge Client

Parameters:

  • hostIP (string) –

    The IP of the ADS host (server)

  • hostPort (int) –

    The port of the ADS host (server)

src.sim.bridgeClient.ApolloBridgeClient_ActorGTPublisher.sendActorGroundTruth(dataList)

Function to send actor ground truth data from the simulator

Parameters:

  • dataList (tuple) –

    Contains all parameters regarding actors in the simulation frame

src.sim.bridgeClient.ApolloBridgeClient_ActorGTPublisher.sendSensorData(data, type)

Wrapper function to send sensor data using the netstruct protocol

Parameters:

  • data (bytestring) –

    Sensor data as a bytestring

  • type (string) –

    String specifying type of sensor data

src.sim.bridgeClient.ApolloBridgeClient_EgoPublisher(hostIP, hostPort)

Bases: BridgeClient

Generic Bridge Client

Parameters:

  • hostIP (string) –

    The IP of the ADS host (server)

  • hostPort (int) –

    The port of the ADS host (server)

src.sim.bridgeClient.ApolloBridgeClient_EgoPublisher.sendEgoData(dataList)

Function to send ego vehicle localization and other data to the ADS. Some of the localization messages are not sent, as specified by the 'enableLocMsgs' flag. This is because Apollo does not need all the localization messages to drive.

Parameters:

  • dataList (tuple) –

    Contains all parameters regarding the ego in the simulation frame

src.sim.bridgeClient.ApolloBridgeClient_ImgPublisher(hostIP, hostPort)

Bases: BridgeClient

Generic Bridge Client

Parameters:

  • hostIP (string) –

    The IP of the ads host (server)

  • hostPort (int) –

    The port of the ads host (server)

src.sim.bridgeClient.ApolloBridgeClient_ImgPublisher.sendImgData(imgData)

Function to send image data from simulator to ADS

Parameters:

  • imgData –

    Image data from the simulator

src.sim.bridgeClient.ApolloBridgeClient_ImgPublisher.sendcImgData(cimgData)

Function to send compressed image data from simulator to ADS

Parameters:

  • cimgData –

    Compressed image data from the simulator

src.sim.bridgeClient.ApolloBridgeClient_PCPublisher(hostIP, hostPort)

Bases: BridgeClient

Generic Bridge Client

Parameters:

  • hostIP (string) –

    The IP of the ads host (server)

  • hostPort (int) –

    The port of the ads host (server)

src.sim.bridgeClient.ApolloBridgeClient_PCPublisher.sendPCData(PCData)

Function to send pointcloud data from simulator to ADS

Parameters:

  • cimgData –

    Compressed image data from the simulator

src.sim.bridgeClient.ApolloBridgeClient_Subscriber(hostIP, hostPort)

Bases: BridgeClient

Generic Bridge Client

Parameters:

  • hostIP (string) –

    The IP of the ads host (server)

  • hostPort (int) –

    The port of the ads host (server)

src.sim.bridgeClient.ApolloBridgeClient_Subscriber.decodeSimData(binMsg)

Function to decode the control command data received from the ADS

Parameters:

  • binMsg (bytestring) –

    Binary message from the ADS to be decoded

src.sim.bridgeClient.BridgeClient(hostIP, hostPort, msgString, delay=None, nextMsgTime=None)

Generic Bridge Client

Parameters:

  • hostIP (string) –

    The IP of the ads host (server)

  • hostPort (int) –

    The port of the ads host (server)

  • msgString (bstring) –

    string ID of the client

  • delay (float, default: None ) –

    time delay between each message

  • nextMsgTime (float, default: None ) –

    store the expected timestamp of the next message

src.sim.bridgeClient.BridgeClient.closeConnection()

Close the connection to the server

src.sim.bridgeClient.BridgeClient.computeNextMsgTime(now, prevMsg, delay)

When a message is sent, determines the timestamp of the next message and wheter to skip frames in case of excessive accumulation

Parameters:

  • now (float) –

    Current timestamp

  • prevMsg (float) –

    Expected time of the previous message

  • delay (float) –

    Expected delay of this message stream

Returns:

src.sim.bridgeClient.BridgeClient.connectToServer()

Initiate connection

src.sim.bridgeClient.BridgeClient.decodeSimData(binMsg)

Decodes and return the message received from the server, to be customized based on the client role.

src.sim.bridgeClient.BridgeClient.recvMsg()

Netstruct function to receive message from apolloBridgeServer

src.sim.bridgeClient.BridgeClient.recvSimData()

Function to receive messages from the server

Returns:

  • –

    The message from the server, decoded with self.decodeSimData

src.sim.bridgeClient.BridgeClient.register()

Register a client object to the server

src.sim.bridgeClient.BridgeClient.sendBinMsg(data, msgType)

Netstruct protocol function to package and send binary data

Parameters:

  • data (bytestring) –

    The data to send

  • msgType (string) –

    Message type

apolloEncode.py

src.sim.apolloEncode.ConvertPoints(carlaPoint, t)

Convert Carla points from the pointcloud to the Protobuf PointXYZIT format

Parameters:

  • carlaPoint –

    Point from each Carla pointcloud frame

  • t (float) –

    Timestamp

Returns:

  • –

    Point in the PointXYZIT format

src.sim.apolloEncode.encode_BPmsgs(lat, lon, utmx, utmy, t, seq)

Package and serialize ego vehicle Best Pose data from the simulator to Apollo's format

Parameters:

  • lat (float) –

    Latitude

  • lon (float) –

    Longitude

  • utmx (float) –

    UTM X-coordinate

  • utmy (float) –

    UTM Y-coordinate

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

Returns:

  • –

    Best Pose message as a bytestring

src.sim.apolloEncode.encode_Chamsgs(t, lat, lon, utmx, utmy, odo, heading, vel, throttle, brake, steering)

Package and serialize ego vehicle chassis data from the simulator to Apollo's format

Parameters:

  • t (float) –

    Timestamp

  • lat (float) –

    Latitude

  • lon (float) –

    Longitude

  • utmx (float) –

    UTM X-coordinate

  • utmy (float) –

    UTM Y-coordinate

  • odo (float) –

    Odometer reading

  • heading (float) –

    Heading

  • vel (float) –

    Absolute velocity

  • throttle (float) –

    Throttle percentage

  • brake (float) –

    Brake percentage

  • steering (float) –

    Steering angle

Returns:

  • –

    Chassis message as a bytestring

src.sim.apolloEncode.encode_CompressedIMG(imgData, seq)

Package and serialize compressed camera images from the simulator to Apollo's format

Parameters:

  • imgData –

    Image data from the simulator

  • seq (int) –

    Sequence number

Returns:

  • –

    Compressed image data as a bytestring

src.sim.apolloEncode.encode_GPSmsg(lat, lon, utmx, utmy, qw, qx, qy, qz, velx, vely, heading, t, seq)

Package and serialize ego vehicle GPS data from the simulator to Apollo's format

Parameters:

  • lat (float) –

    Latitude

  • lon (float) –

    Longitude

  • utmx (float) –

    UTM X-coordinate

  • utmy (float) –

    UTM Y-coordinate

  • qw (float) –

    Quaternion W

  • qx (float) –

    Quaternion X

  • qy (float) –

    Quaternion Y

  • qz (float) –

    Quaternion Z

  • velx (float) –

    Velocity in X-axis

  • vely (float) –

    Velocity in Y-axis

  • heading (float) –

    Heading

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

Returns:

  • –

    GPS message as a bytestring

src.sim.apolloEncode.encode_Heamsgs(t, seq, heading)

Package and serialize ego vehicle heading from the simulator to Apollo's format

Parameters:

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

  • heading (float) –

    Heading

Returns:

  • –

    Heading message as a bytestring

src.sim.apolloEncode.encode_IMG(imgData, seq)

Package and serialize camera images from the simulator to Apollo's format

Parameters:

  • imgData –

    Image data from the simulator

  • seq (int) –

    Sequence number

Returns:

  • –

    Image data as a bytestring

src.sim.apolloEncode.encode_IMUmsgs(avelX, avelY, avelZ, accX, accY, accZ, t, seq)

Package and serialize ego vehicle IMU data from the simulator to Apollo's format

Parameters:

  • avelX (float) –

    Angular velocity in the X-axis

  • avelY (float) –

    Angular velocity in the Y-axis

  • avelZ (float) –

    Angular velocity in the Z-axis

  • accX (float) –

    Acceleration in the X-axis

  • accY (float) –

    Acceleration in the Y-axis

  • accZ (float) –

    Acceleration in the Z-axis

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

Returns:

  • –

    IMU message as a bytestring

src.sim.apolloEncode.encode_INSmsgs(t, seq)

Package and serialize ego vehicle INS data from the simulator to Apollo's format

Parameters:

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

Returns:

  • –

    INS message as a bytestring

src.sim.apolloEncode.encode_PC(pcData, seq)

Package and serialize LiDAR pointcloud from the simulator to Apollo's format

Parameters:

  • pcData –

    Pointcloud data from the simulator

  • seq (int) –

    Sequence number

Returns:

  • –

    Pointcloud message as a bytestring

src.sim.apolloEncode.encode_POmsgs(objCount, objIDs, objType, objHeadings, objLats, objLons, objutmx, objutmy, objVelXs, objVelYs, objBBxs, objBBys, objBBzs, t, seq)

Package and serialize actor snapshot data from the simulator into Apollo's Perception Obstacle message

Parameters:

  • objCount (int) –

    Number of objects/obstacles in current simulation snapshot

  • objIDs (list) –

    Unique identifier assigned to each object/obstacle

  • objType (string) –

    Type of object (vehicle, pedestrian, cones etc.)

  • objHeadings (float) –

    Heading of each object

  • objLats (float) –

    Latitude of each object

  • objLons (float) –

    Longitude of each object

  • objutmx (float) –

    UTM X-coordinate of each object

  • objutmy (float) –

    UTM Y-coordinate of each object

  • objVelXs (float) –

    Velocity of each object in the X-axis

  • objVelYs (float) –

    Velocity of each object in the Y-axis

  • objBBxs (float) –

    Bounding box dimension of each object in the X-axis

  • objBBys (float) –

    Bounding box dimension of each object in the Y-axis

  • objBBzs (float) –

    Bounding box dimension of each object in the Z-axis

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

Returns: Perception Obstacles message as a bytestring

src.sim.apolloEncode.encode_Posemsgs(lat, lon, utmx, utmy, qw, qx, qy, qz, velx, vely, heading, avelX, avelY, avelZ, accX, accY, accZ, t, seq)

Package and serialize ego vehicle pose from the simulator to Apollo's format

Parameters:

  • lat (float) –

    Latitude

  • lon (float) –

    Longitude

  • utmx (float) –

    UTM X-coordinate

  • utmy (float) –

    UTM Y-coordinate

  • qw (float) –

    Quaternion W

  • qx (float) –

    Quaternion X

  • qy (float) –

    Quaternion Y

  • qz (float) –

    Quaternion Z

  • velx (float) –

    Velocity in X-axis

  • vely (float) –

    Velocity in Y-axis

  • heading (float) –

    Heading

  • avelX (float) –

    Angular velocity in X-axis

  • avelY (float) –

    Angular velocity in Y-axis

  • avelZ (float) –

    Angular velocity in Z-axis

  • accX (float) –

    Acceleration in X-axis

  • accY (float) –

    Acceleration in Y-axis

  • accZ (float) –

    Acceleration in Z-axis

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

Returns:

  • –

    Pose message as a bytestring

src.sim.apolloEncode.encode_Tfmsgs(utmx, utmy, eulx, euly, eulz, t, seq)

Package and serialize ego vehicle transform from the simulator to Apollo's format

Parameters:

  • utmx (float) –

    UTM X-coordinate

  • utmy (float) –

    UTM Y-coordinate

  • eulx (float) –

    Euler angle in the X-axis

  • euly (float) –

    Euler angle in the Y-axis

  • eulz (float) –

    Euler angle in the Z-axis

  • t (float) –

    Timestamp

  • seq (int) –

    Sequence number

Returns:

  • –

    Transform message as a bytestring

src.sim.apolloEncode.encode_corrIMUmsgs(avelX, avelY, avelZ, eulX, eulY, eulZ, accX, accY, accZ, heading, t)

Package and serialize ego vehicle Corrected IMU data from the simulator to Apollo's format

Parameters:

  • avelX (float) –

    Angular velocity in the X-axis

  • avelY (float) –

    Angular velocity in the Y-axis

  • avelZ (float) –

    Angular velocity in the Z-axis

  • eulX (float) –

    Euler angle in the X-axis

  • eulY (float) –

    Euler angle in the Y-axis

  • eulZ (float) –

    Euler angle in the Z-axis

  • accX (float) –

    Acceleration in the X-axis

  • accY (float) –

    Acceleration in the Y-axis

  • accZ (float) –

    Acceleration in the Z-axis

  • heading (float) –

    Heading (yaw)

  • t (float) –

    Timestamp

Returns:

  • –

    Corrected IMU message as a bytestring