soar.robot.arcos¶

ARCOS (Advanced Robot Control and Operations Software) Client.

Classes and functions for communicating with an ARCOS server running on an Adept MobileRobot platform (typically Pioneer 2 and 3).

soar.robot.arcos.ADSEL = 35¶: Select the A/D port number for reporting ANPORT value in standard SIP.

class soar.robot.arcos.ARCOSClient(timeout=1.0, write_timeout=1.0, allowed_timeouts=2)¶

Bases: object

An ARCOS Client communicating over a serial port with an ARCOS server.

Parameters:	timeout (float) – The time to wait while receiving data before a timeout occurs, in seconds. write_timeout (float) – The time to wait while sending data before a timeout occurs, in seconds. allowed_timeouts (int) – The number of timeouts to tolerate before the update coroutine closes the port.

standard¶: dict – The last standard Server Information Packet (SIP) received, or None, if one hasn’t been received yet.

config¶: dict – The last CONFIGpac SIP received, or None, if one hasn’t been received yet.

encoder¶: dict – The last ENCODERpac SIP received, or None, if one hasn’t been received yet.

io¶: dict – The last IOpac SIP received, or None, if one hasn’t been received yet.

standard_event¶: threading.Event – Set whenever a standard SIP is received.

config_event¶: threading.Event – Set whenever a CONFIGpac SIP is received.

encoder_event¶: threading.Event – Set whenever an ENCODERpac SIP is received.

io_event¶: threading.Event – Set whenever an IOpac is received.

sonars¶: list – A list of the latest sonar array values, updated whenever a standard SIP is received.

connect(forced_ports=None)¶

Attempt to connect and sync with an ARCOS server over a serial port.

Returns if successful.

Parameters:	forced_ports (list, optional) – If provided, a list of serial ports to try connecting to. Otherwise, the client will try all available ports.
Raises:	`ARCOSError` – If unable to connect to any available ports.

disconnect()¶: Stop the ARCOS server and close the connection if running.

pulse()¶: Continually send the PULSE command so that the robot knows the client is alive.

receive_packet()¶

Read an entire ARCOS Packet from an open port, including header and checksum bytes.

Returns:	The entire packet as a list of bytes, including header and checksum bytes.
Return type:	list
Raises:	`Timeout` – If at any point a timeout occurs and fewer bytes than expected are read. `InvalidPacket` – If the packet header, checksum, or packet length are invalid. `ARCOSError` – If something went wrong reading from the serial port.

send_command(code, data=None, append_null=True)¶

Send a command and data to the ARCOS server.

Parameters:	code – The command code. Must be in `soar.robot.arcos.command_types`. data (optional) – The associated command argument, assumed to be of the correct type. For commands that take a string argument, a `bytes` object may also be used. append_null (optional) – If `True`, append a null byte to any `str` or `bytes` object passed as a command argument.
Raises:	`Timeout` – If the write timeout of the port was exceeded. `ARCOSError` – If an error occurred writing to the serial port.

send_packet(*data)¶

Send arbitrary data to the ARCOS server.

Adds the packet header and checksum. Thread-safe.

Parameters:	*data – A tuple or iterable of bytes, whose values are assumed to be between 0 and 255, inclusive.
Raises:	`Timeout` – If the write timeout of the serial port was exceeded. `ARCOSError` – If something went wrong writing to the serial port.

start()¶: Open the ARCOS servers, enable the sonars, and start the pulse & update coroutines.

sync(tries=4)¶

Try to sync with an ARCOS server connected over an open serial port.

Returns the raw robot identifying information packet sent after SYNC2 if successful.

Parameters:	tries (int, optional) – The number of failures to tolerate before timing out.
Raises:	`Timeout` – If the number of tries is exhausted and syncing was not completed.

update()¶: Continually receive and decode packets, storing them as attributes and triggering events.

static wait_or_timeout(event, timeout=1.0, timeout_msg='')¶

Wait for an event to occur, with an optional timeout and message.

Parameters:	event (Event) – The event to wait for. Expected to be one of the attribute events of this class. timeout (float, optional) – How long to wait for the event before timing out. timeout_msg (str) – The message to pass if a timeout occurs.
Raises:	`Timeout` – If the event has not occurred by the specified time.

exception soar.robot.arcos.ARCOSError¶

Bases: soar.errors.SoarIOError

Umbrella class for ARCOS-related exceptions.

soar.robot.arcos.BUMPSTALL = 44¶: Stall robot if no (0), only front (1), only rear (2), or either (3) bumpers make contact.

soar.robot.arcos.CLOSE = 2¶: Close servers and client connection. Also stops the robot.

soar.robot.arcos.CONFIG = 18¶: Request a configuration SIP.

soar.robot.arcos.DCHEAD = 22¶: Adjust heading relative to last setpoint; +- degrees (+ is counterclockwise).

soar.robot.arcos.DHEAD = 13¶: Turn at SETRV speed relative to current heading; (+) counterclockwise or (-) clockwise degrees.

soar.robot.arcos.DIGOUT = 30¶: Set (1) or reset (0) user output ports. High bits 8-15 is a byte mask that selects the ports to change; low bits 0-7 set (1) or reset (0) the selected port(s).

soar.robot.arcos.ENABLE = 4¶: Enable the motors, if argument is 1, or disable them if it is 0.

soar.robot.arcos.ENCODER = 19¶: Request a single (1), a continuous stream (>1), or stop (0) encoder SIPS.

soar.robot.arcos.E_STOP = 55¶: Emergency stop. Overrides acceleration, so is very abrupt.

soar.robot.arcos.HEAD = 12¶: Turn at SETRV speed to absolute heading; +-degrees (+ is counterclockwise).

soar.robot.arcos.IOREQUEST = 40¶: Request a single (1), a continuous stream (>1), or stop (0) IO SIPS.

exception soar.robot.arcos.InvalidPacket¶

Bases: soar.robot.arcos.ARCOSError

Raised when a packet’s checksum is incorrect.

soar.robot.arcos.MOVE = 8¶: Translate forward (+) or backward (-) mm absolute distance at SETV speed.

soar.robot.arcos.OPEN = 1¶: Start the ARCOS servers.

soar.robot.arcos.POLLING = 3¶: Change sonar polling sequence. Argument is a string consisting of sonar numbers 1-32 (as single bytes).

soar.robot.arcos.PULSE = 0¶: Reset server watchdog (typically sent every second so that the robot knows the client is alive).

soar.robot.arcos.ROTATE = 9¶: Rotate counter- (+) or clockwise (-) degrees/sec at SETRV limited speed.

soar.robot.arcos.RVEL = 21¶: Rotate (degrees/sec) counterclockwise (+) or clockwise (-). Limited by SETRV.

soar.robot.arcos.SAY = 15¶: Play up to 20 duration, tone sound pairs through User Control panel piezo speaker. The argument is a string whose first byte must be the number of (duration, tone) pairs to play, followed by each (duration, tone) pair. Duration is in 20 millisecond increments. A value of 0 means silence. The values 1-127 are the corresponding MIDI notes, with 60 being middle C. The remaining values are frequencies computed as (tone - 127)*32, ranging from 1-4096 in 32Hz increments.

soar.robot.arcos.SETA = 5¶: Set translation acceleration, if positive, or deceleration, if negative, in mm/sec^2.

soar.robot.arcos.SETO = 7¶: Reset local odometry position to the origin (0, 0, 0).

soar.robot.arcos.SETRA = 23¶: Change rotation (+) acceleration or (-) deceleration in degrees/sec^2

soar.robot.arcos.SETRV = 10¶: Set maximum rotation velocity in degrees/sec. Note that the robot is still limited by the hardware cap.

soar.robot.arcos.SETV = 6¶: Set maximum translational velocity in mm/sec. Note that the robot is still limited by the hardware cap.

soar.robot.arcos.SONAR = 28¶: 1=enable, 0=disable all the sonar; otherwise bits 1-3 specify an array from 1-4 to enable/disable.

soar.robot.arcos.SONARCYCLE = 48¶: Change the sonar cycle time, in milliseconds.

soar.robot.arcos.SOUNDTOG = 92¶: Mute (0) or enable (1) the user control piezo speaker.

soar.robot.arcos.STOP = 29¶: Stop the robot without disabling the motors.

soar.robot.arcos.SYNC0 = 0¶: The initial synchronization packet.

soar.robot.arcos.SYNC1 = 1¶: The second synchronization packet.

exception soar.robot.arcos.Timeout¶

Bases: soar.robot.arcos.ARCOSError

Raised when no packet is read after a certain interval.

soar.robot.arcos.VEL = 11¶: Translate at mm/sec forward (+) or backward (-), capped by SETV.

soar.robot.arcos.VEL2 = 32¶: Set independent wheel velocities; bits 0-7 for right wheel, bits 8-15 for left in 20mm/sec increments.

soar.robot.arcos.command_types = {0: None, 1: None, 2: None, 3: <class 'str'>, 4: <class 'int'>, 5: <class 'int'>, 6: <class 'int'>, 7: None, 8: <class 'int'>, 9: <class 'int'>, 10: <class 'int'>, 11: <class 'int'>, 12: <class 'int'>, 13: <class 'int'>, 15: <class 'str'>, 18: None, 19: <class 'int'>, 21: <class 'int'>, 22: <class 'int'>, 23: <class 'int'>, 28: <class 'int'>, 29: None, 30: <class 'int'>, 32: <class 'int'>, 35: <class 'int'>, 40: <class 'int'>, 44: <class 'int'>, 48: <class 'int'>, 55: None, 92: <class 'int'>}¶: The argument type of every supported ARCOS command.

soar.robot.arcos.decode_packet(packet)¶

Decode a SIP (Server Information Packet) into a field-indexable dictionary.

Returns:	A dictionary with field names as keys and values as corresponding numbers. The `'TYPE'` key holds a value of `'STANDARD'`, `'CONFIG'`, `'ENCODER'`, or `'IO'`, corresponding to the packet type.
Return type:	dict
Raises:	`InvalidPacket` – If a packet’s fields could not be decoded.

soar.robot.arcos.packet_checksum(data)¶

Calculate and returns the ARCOS packet checksum of a packet which does not have one.

Parameters:	data (list) – A list of data bytes.
Returns:	The packet checksum.
Return type:	int