#!/usr/bin/env python
import roslib; roslib.load_manifest('ur5_driver')
import time, sys, threading, math
import copy
import datetime
import socket, select
import struct
import traceback, code
import optparse
import SocketServer
import rospy
import actionlib
from sensor_msgs.msg import JointState
from control_msgs.msg import FollowJointTrajectoryAction
from trajectory_msgs.msg import JointTrajectory, JointTrajectoryPoint
PORT=30001
MSG_OUT = 1
MSG_QUIT = 2
MSG_JOINT_STATES = 3
MSG_MOVEJ = 4
MSG_WAYPOINT_FINISHED = 5
MSG_STOPJ = 6
MSG_SERVOJ = 7
MULT_jointstate = 1000.0
MULT_time = 1000000.0
MULT_blend = 1000.0
JOINT_NAMES = ['shoulder_pan_joint', 'shoulder_lift_joint', 'elbow_joint',
'wrist_1_joint', 'wrist_2_joint', 'wrist_3_joint']
Q1 = [2.2,0,-1.57,0,0,0]
Q2 = [1.5,0,-1.57,0,0,0]
Q3 = [1.5,-0.2,-1.57,0,0,0]
connected_robot = None
connected_robot_lock = threading.Lock()
connected_robot_cond = threading.Condition(connected_robot_lock)
pub_joint_states = rospy.Publisher('joint_states', JointState)
dump_state = open('dump_state', 'wb')
class EOF(Exception): pass
def dumpstacks():
id2name = dict([(th.ident, th.name) for th in threading.enumerate()])
code = []
for threadId, stack in sys._current_frames().items():
code.append("\n# Thread: %s(%d)" % (id2name.get(threadId,""), threadId))
for filename, lineno, name, line in traceback.extract_stack(stack):
code.append('File: "%s", line %d, in %s' % (filename, lineno, name))
if line:
code.append(" %s" % (line.strip()))
print "\n".join(code)
def log(s):
print "[%s] %s" % (datetime.datetime.now().strftime('%Y-%m-%d %H:%M:%S.%f'), s)
def setConnectedRobot(r):
global connected_robot, connected_robot_lock
with connected_robot_lock:
connected_robot = r
connected_robot_cond.notify()
def getConnectedRobot(wait=False, timeout=-1):
started = time.time()
with connected_robot_lock:
if wait:
while not connected_robot:
if timeout >= 0 and time.time() > started + timeout:
break
connected_robot_cond.wait(0.2)
return connected_robot
# Receives messages from the robot over the socket
class CommanderTCPHandler(SocketServer.BaseRequestHandler):
def recv_more(self):
while True:
r, _, _ = select.select([self.request], [], [], 0.2)
if r:
more = self.request.recv(4096)
if not more:
raise EOF()
return more
else:
if self.last_joint_states and \
self.last_joint_states.header.stamp.to_sec() < time.time() + 1.0:
rospy.logerr("Stopped hearing from robot. Disconnected")
raise EOF()
def handle(self):
self.socket_lock = threading.Lock()
self.last_joint_states = None
setConnectedRobot(self)
print "Handling a request"
try:
buf = self.recv_more()
if not buf: return
while True:
#print "Buf:", [ord(b) for b in buf]
# Unpacks the message type
mtype = struct.unpack_from("!i", buf, 0)[0]
buf = buf[4:]
#print "Message type:", mtype
if mtype == MSG_OUT:
# Unpacks string message, terminated by tilde
i = buf.find("~")
while i < 0:
buf = buf + self.recv_more()
i = buf.find("~")
if len(buf) > 2000:
raise Exception("Probably forgot to terminate a string: %s..." % buf[:150])
s, buf = buf[:i], buf[i+1:]
log("Out: %s" % s)
elif mtype == MSG_JOINT_STATES:
while len(buf) < 3*(6*4):
buf = buf + self.recv_more()
state_mult = struct.unpack_from("!%ii" % (3*6), buf, 0)
buf = buf[3*6*4:]
state = [s / MULT_jointstate for s in state_mult]
msg = JointState()
msg.header.stamp = rospy.get_rostime()
msg.name = JOINT_NAMES
msg.position = state[:6]
msg.velocity = state[6:12]
msg.effort = state[12:18]
pub_joint_states.publish(msg)
self.last_joint_states = msg
elif mtype == MSG_QUIT:
print "Quitting"
raise EOF()
elif mtype == MSG_WAYPOINT_FINISHED:
while len(buf) < 4:
buf = buf + self.recv_more()
waypoint_id = struct.unpack_from("!i", buf, 0)[0]
buf = buf[4:]
print "Waypoint finished (not handled)"
else:
raise Exception("Unknown message type: %i" % mtype)
if not buf:
buf = buf + self.recv_more()
except EOF:
print "Connection closed (command)"
setConnectedRobot(None)
def send_quit(self):
with self.socket_lock:
self.request.send(struct.pack("!i", MSG_QUIT))
def send_movej(self, waypoint_id, q, a=3, v=0.75, t=0, r=0):
assert(len(q) == 6)
params = [MSG_MOVEJ, waypoint_id] + \
[MULT_jointstate * qq for qq in q] + \
[MULT_jointstate * a, MULT_jointstate * v, MULT_time * t, MULT_blend * r]
buf = struct.pack("!%ii" % len(params), *params)
with self.socket_lock:
self.request.send(buf)
def send_servoj(self, waypoint_id, q, t):
assert(len(q) == 6)
params = [MSG_SERVOJ, waypoint_id] + \
[MULT_jointstate * qq for qq in q] + \
[MULT_time * t]
buf = struct.pack("!%ii" % len(params), *params)
with self.socket_lock:
self.request.send(buf)
def send_stopj(self):
with self.socket_lock:
self.request.send(struct.pack("!i", MSG_STOPJ))
def set_waypoint_finished_cb(self, cb):
self.waypoint_finished_cb = cb
# Returns the last JointState message sent out
def get_joint_states(self):
return self.last_joint_states
class TCPServer(SocketServer.TCPServer):
allow_reuse_address = True # Allows the program to restart gracefully on crash
timeout = 5
# Waits until all threads have completed. Allows KeyboardInterrupt to occur
def joinAll(threads):
while any(t.isAlive() for t in threads):
for t in threads:
t.join(0.2)
# Returns the duration between moving from point (index-1) to point
# index in the given JointTrajectory
def get_segment_duration(traj, index):
if index == 0:
return traj.points[0].time_from_start.to_sec()
return (traj.points[index].time_from_start - traj.points[index-1].time_from_start).to_sec()
# Reorders the JointTrajectory traj according to the order in
# joint_names. Destructive.
def reorder_traj_joints(traj, joint_names):
order = [traj.joint_names.index(j) for j in joint_names]
new_points = []
for p in traj.points:
new_points.append(JointTrajectoryPoint(
positions = [p.positions[i] for i in order],
velocities = [p.velocities[i] for i in order] if p.velocities else [],
accelerations = [p.accelerations[i] for i in order] if p.accelerations else [],
time_from_start = p.time_from_start))
traj.joint_names = joint_names
traj.points = new_points
def interp_cubic(p0, p1, t_abs):
T = (p1.time_from_start - p0.time_from_start).to_sec()
t = t_abs - p0.time_from_start.to_sec()
q = [0] * 6
qdot = [0] * 6
qddot = [0] * 6
for i in range(len(p0.positions)):
a = p0.positions[i]
b = p0.velocities[i]
c = (-3*p0.positions[i] + 3*p1.positions[i] - 2*T*p0.velocities[i] - T*p1.velocities[i]) / T**2
d = (2*p0.positions[i] - 2*p1.positions[i] + T*p0.velocities[i] + T*p1.velocities[i]) / T**3
q[i] = a + b*t + c*t**2 + d*t**3
qdot[i] = b + 2*c*t + 3*d*t**2
qddot[i] = 2*c + 6*d*t
return JointTrajectoryPoint(q, qdot, qddot, rospy.Duration(t_abs))
# Returns (q, qdot, qddot) for sampling the JointTrajectory at time t.
# The time t is the time since the trajectory was started.
def sample_traj(traj, t):
# First point
if t <= 0.0:
return copy.deepcopy(traj.points[0])
# Last point
if t >= traj.points[-1].time_from_start.to_sec():
return copy.deepcopy(traj.points[-1])
# Finds the (middle) segment containing t
i = 0
while traj.points[i+1].time_from_start.to_sec() < t:
i += 1
return interp_cubic(traj.points[i], traj.points[i+1], t)
class UR5TrajectoryFollower(object):
RATE = 0.02
def __init__(self, robot):
self.following_lock = threading.Lock()
self.T0 = time.time()
self.robot = robot
self.server = actionlib.ActionServer("follow_joint_trajectory",
FollowJointTrajectoryAction,
self.on_goal, self.on_cancel, auto_start=False)
self.goal_handle = None
self.traj = None
self.traj_t0 = 0.0
self.first_waypoint_id = 10
self.tracking_i = 0
self.pending_i = 0
self.update_timer = rospy.Timer(rospy.Duration(self.RATE), self._update)
def set_robot(self, robot):
# Cancels any goals in progress
if self.goal_handle:
self.goal_handle.set_canceled()
self.goal_handle = None
self.traj = None
self.robot = robot
if self.robot:
self.init_traj_from_robot()
# Sets the trajectory to remain stationary at the current position
# of the robot.
def init_traj_from_robot(self):
if not self.robot: raise Exception("No robot connected")
# Busy wait (avoids another mutex)
state = self.robot.get_joint_states()
while not state:
time.sleep(0.1)
state = self.robot.get_joint_states()
self.traj_t0 = time.time()
self.traj = JointTrajectory()
self.traj.joint_names = JOINT_NAMES
self.traj.points = [JointTrajectoryPoint(
positions = state.position,
velocities = [0] * 6,
accelerations = [0] * 6,
time_from_start = rospy.Duration(0.0))]
def start(self):
self.init_traj_from_robot()
self.server.start()
def on_goal(self, goal_handle):
log("on_goal")
# Checks that the robot is connected
if not self.robot:
rospy.logerr("Received a goal, but the robot is not connected")
goal_handle.set_rejected()
return
# Checks if the joints are just incorrect
if set(goal_handle.get_goal().trajectory.joint_names) != set(JOINT_NAMES):
rospy.logerr("Received a goal with incorrect joint names: (%s)" % \
', '.join(goal_handle.get_goal().trajectory.joint_names))
goal_handle.set_rejected()
return
# Orders the joints of the trajectory according to JOINT_NAMES
reorder_traj_joints(goal_handle.get_goal().trajectory, JOINT_NAMES)
with self.following_lock:
if self.goal_handle:
# Cancels the existing goal
self.goal_handle.set_canceled()
self.first_waypoint_id += len(self.goal_handle.get_goal().trajectory.points)
self.goal_handle = None
# Inserts the current setpoint at the head of the trajectory
now = time.time()
point0 = sample_traj(self.traj, now)
point0.time_from_start = rospy.Duration(0.0)
goal_handle.get_goal().trajectory.points.insert(0, point0)
self.traj_t0 = now
# Replaces the goal
self.goal_handle = goal_handle
self.traj = goal_handle.get_goal().trajectory
self.goal_handle.set_accepted()
def on_cancel(self, goal_handle):
log("on_cancel")
if goal_handle == self.goal_handle:
with self.following_lock:
# Uses the next little bit of trajectory to slow to a stop
STOP_DURATION = 0.5
now = time.time()
point0 = sample_traj(self.traj, now - self.traj_t0)
point0.time_from_start = rospy.Duration(0.0)
point1 = sample_traj(self.traj, now - self.traj_t0 + STOP_DURATION)
point1.velocities = [0] * 6
point1.accelerations = [0] * 6
point1.time_from_start = rospy.Duration(STOP_DURATION)
self.traj_t0 = now
self.traj = JointTrajectory()
self.traj.joint_names = JOINT_NAMES
self.traj.points = [point0, point1]
self.goal_handle.set_canceled()
self.goal_handle = None
else:
goal_handle.set_canceled()
def _update(self, event):
if self.robot and self.traj:
now = time.time()
if (now - self.traj_t0) <= self.traj.points[-1].time_from_start.to_sec():
setpoint = sample_traj(self.traj, now - self.traj_t0)
try:
self.robot.send_servoj(999, setpoint.positions, 2 * self.RATE)
except socket.error:
pass
else: # Off the end
if self.goal_handle:
self.goal_handle.set_succeeded()
self.goal_handle = None
sock = None
def main():
global sock
rospy.init_node('ur5_driver', disable_signals=True)
if rospy.get_param("use_sim_time", False):
rospy.logfatal("use_sim_time is set!!!")
sys.exit(1)
# Parses command line arguments
parser = optparse.OptionParser(usage="usage: %prog robot_hostname")
(options, args) = parser.parse_args(rospy.myargv()[1:])
if len(args) != 1:
parser.error("You must specify the robot hostname")
robot_hostname = args[0]
# Sets up the server for the robot to connect to
server = TCPServer(("", 50001), CommanderTCPHandler)
thread_commander = threading.Thread(name="CommanderHandler", target=server.serve_forever)
thread_commander.daemon = True
thread_commander.start()
action_server = None
try:
while True:
# Checks for disconnect
if getConnectedRobot(wait=False):
time.sleep(0.2)
else:
print "Disconnected. Reconnecting"
if action_server:
action_server.set_robot(None)
rospy.loginfo("Programming the robot")
while True:
# Sends the program to the robot
sock = socket.create_connection((robot_hostname, PORT))
with open('prog') as fin:
program = fin.read()
sock.sendall(program % {"driver_hostname": socket.getfqdn()})
# Useful for determining if the robot failed to compile the program
if False:
print "Dump"
print "="*70
o = ""
while len(o) < 4096:
r = sock.recv(1024)
if not r: break
o = o + r
print o
r = getConnectedRobot(wait=True, timeout=1.0)
if r:
break
rospy.loginfo("Robot connected")
if action_server:
action_server.set_robot(r)
else:
action_server = UR5TrajectoryFollower(r)
action_server.start()
except KeyboardInterrupt:
try:
rospy.signal_shutdown("KeyboardInterrupt")
if r: r.send_quit()
except:
pass
raise
if __name__ == '__main__': main()