for y in xrange(1, 19):
occupancyGrid.setCell(11, y, 1)
# Start and goal cells
start = (3, 18)
goal = (20, 0)
# Create the planner on the original map
planner = FIFOPlanner('Depth First Search Original Occupancy Grid',
occupancyGrid)
planner.setWindowHeightInPixels(400)
planner.search(start, goal)
path = planner.extractPathToGoal()
# Now try it on our Minkowski sum map with radius 0.5 (1 cell)
occupancyGrid.expandObstaclesToAccountForCircularRobotOfRadius(0.5)
planner = FIFOPlanner('Depth First Search Robot Radius 0.5', occupancyGrid)
planner.setWindowHeightInPixels(400)
planner.search(start, goal)
path = planner.extractPathToGoal()
# Now try it on our Minkowski sum map with radius 0. Should be the same as the original
occupancyGrid.expandObstaclesToAccountForCircularRobotOfRadius(0)
planner = FIFOPlanner(
'Depth First Search Robot Radius 0 (Same As Original Map)', occupancyGrid)
planner.setWindowHeightInPixels(400)
planner.search(start, goal)
path = planner.extractPathToGoal()
# Now try it on our Minkowski sum map with a radius of 2 (4 cells). In this case, the
# robot can't get there from here.
class PlannerControllerNode(object):
def __init__(self):
rospy.init_node('planner_controller', anonymous=True)
self.waitForGoal = threading.Condition()
self.waitForDriveCompleted = threading.Condition()
self.goal = None
pass
def createOccupancyGridFromMapServer(self):
# Get the map service
rospy.loginfo('Waiting for static_map to become available.')
rospy.wait_for_service('static_map')
self.mapServer = rospy.ServiceProxy('static_map', GetMap)
rospy.loginfo('Found static_map; requesting map data')
# Query the map status
response = self.mapServer()
map = response.map
rospy.loginfo('Got map data')
# Allocate the occupancy grid and set the data from the array sent back by the map server
self.occupancyGrid = OccupancyGrid(map.info.width, map.info.height,
map.info.resolution)
self.occupancyGrid.setScale(rospy.get_param('plan_scale', 5))
self.occupancyGrid.setFromDataArrayFromMapServer(map.data)
self.occupancyGrid.expandObstaclesToAccountForCircularRobotOfRadius(
0.2)
def createPlanner(self):
self.planner = FIFOPlanner('FIFO', self.occupancyGrid)
self.planner.setPauseTime(0)
self.planner.windowHeightInPixels = rospy.get_param(
'maximum_window_height_in_pixels', 700)
def createRobotController(self):
self.robotController = Move2GoalController(self.occupancyGrid)
def handleDriveToGoal(self, goal):
# Report to the main loop that we have a new goal
self.waitForGoal.acquire()
self.goal = goal
self.waitForGoal.notify()
self.waitForGoal.release()
# Wait until the robot has finished driving
self.waitForDriveCompleted.acquire()
self.waitForDriveCompleted.wait()
self.waitForDriveCompleted.release()
return GoalResponse(True)
# Run the planner. Note that we do not take account of the robot orientation when planning.
# The reason is simplicity; adding orientation means we have a full 3D planning problem.
# As a result, the plan will not be as efficient as it could be.
def driveToGoal(self, goal):
# Get the current pose of the robot
pose = self.robotController.getCurrentPose()
start = (pose.x, pose.y)
print "start = " + str(start)
print "goal = " + str(goal)
# Call the planner
startCellCoords = self.occupancyGrid.getCellCoordinatesFromWorldCoordinates(
start)
goalCellCoords = self.occupancyGrid.getCellCoordinatesFromWorldCoordinates(
(goal.x, goal.y))
print "startCellCoords = " + str(startCellCoords)
print "goalCellCoords = " + str(goalCellCoords)
# Exit if we need to
if rospy.is_shutdown() is True:
return False
# Get the plan
goalReached = self.planner.search(startCellCoords, goalCellCoords)
# Exit if we need to
if rospy.is_shutdown() is True:
return False
# If we can't reach the goal, give up and return
if goalReached is False:
rospy.logwarn("Could not reach the goal at (%d, %d); moving to next goal", \
goalCellCoords[0], goalCellCoords[1])
return False
# Extract the path
path = self.planner.extractPathToGoal()
# Now drive it
self.robotController.drivePathToGoal(path, goal.theta,
self.planner.getPlannerDrawer())
return True
def run(self):
# First set up the occupancy grid
self.createOccupancyGridFromMapServer()
# Create the planner
self.createPlanner()
# Set up the robot controller
self.createRobotController()
# Set up the wait for the service. Note that we can't directly
# handle all the driving operations in the service
# handler. The reason is that the planner can create a GUI,
# and self MUST run in the main thread. The result is pretty
# ugly logic and can lead to deadlocking.
service = rospy.Service('drive_to_goal', Goal, self.handleDriveToGoal)
print 'Spinning to service goal requests'
while not rospy.is_shutdown():
# Wait for a new goal. Allow at most 0.1s, which gives
# time to check if we are shutting down
self.waitForGoal.acquire()
self.waitForGoal.wait(0.1)
self.waitForGoal.release()
# If no goal has been allocated, cycle around
if (self.goal is None):
continue
self.driveToGoal(self.goal)
self.goal = None
# Signal back to the service handler that we are done
self.waitForDriveCompleted.acquire()
self.waitForDriveCompleted.notify()
self.waitForDriveCompleted.release()