X-Git-Url: https://defiant.homedns.org/gitweb/?p=ros_wild_thumper.git;a=blobdiff_plain;f=scripts%2Fdwm1000.py;h=707dff19f05e75865b6371b789daf84a1159db86;hp=a1dac533a75fdff3df52e15de79150042db8869f;hb=f04118a96832b33d160805b1e07e738a41102b84;hpb=d0c13eed893ea8d50dd8f6471af5a19c625d7842

diff --git a/scripts/dwm1000.py b/scripts/dwm1000.py
index a1dac53..707dff1 100755
--- a/scripts/dwm1000.py
+++ b/scripts/dwm1000.py
@@ -14,6 +14,7 @@ from i2c import i2c
 from time import sleep
 from std_msgs.msg import Float32
 from nav_msgs.msg import Odometry
+from wild_thumper.srv import DWM1000Center, DWM1000CenterResponse
 if VISULAIZE:
 	import matplotlib.pyplot as plt
 
@@ -41,6 +42,10 @@ class simple_kalman:
 
 		return x
 
+	def set_measure_cov(self, R):
+		if R > 0:
+			self.R = R
+
 class DW1000(threading.Thread):
 	def __init__(self, name, addr, offset):
 		threading.Thread.__init__(self)
@@ -72,10 +77,10 @@ class DW1000(threading.Thread):
 
 	def run(self):
 		last_val = 10
-		while True:
+		while not rospy.is_shutdown():
 			val = self.get_value()
-			if abs(val - last_val)  > 10:
-				print "Ignoring values too far apart %s: %.2f - %.2f" % (self.name, val, last_val)
+			if abs(val - last_val)  > 50:
+				rospy.logwarn("Ignoring values too far apart %s: %.2f - %.2f", self.name, val, last_val)
 			elif not isnan(val):
 				self.dist = val + self.offset
 				self.last_update = datetime.now()
@@ -92,9 +97,12 @@ class Position:
 		P_est_x = 0.02
 		P_est_y = 0.01
 		# Systemrauschen
-		Q = 0.002
-		self.filter_x = simple_kalman(1.0, P_est_x, Q, Rx)
-		self.filter_y = simple_kalman(0.0, P_est_y, Q, Ry)
+		Qx = 0.001
+		Qy = 0.00001
+		# TODO: Replace 2x 1d kalman with 2d kalman
+		# so the polyfit variance can be replaced with a covariance matrix
+		self.filter_x = simple_kalman(1.0, P_est_x, Qx, Rx)
+		self.filter_y = simple_kalman(0.0, P_est_y, Qy, Ry)
 		self.speed_x = 0
 		self.speed_y = 0
 		self.speed_z = 0
@@ -106,10 +114,6 @@ class Position:
 		self.speed_y = msg.twist.twist.linear.y
 		self.speed_z = msg.twist.twist.angular.z
 
-	"""
-	TODO:
-	- variance of kalman should be dependant on distance
-	"""
 	def filter(self, x, y):
 		# Correct estimation with speed
 		current_time = rospy.Time.now()
@@ -130,6 +134,11 @@ class Position:
 		if x != None and y != None:
 			x = self.filter_x.run(x)
 			y = self.filter_y.run(y)
+
+			# Update variance
+			dist = np.linalg.norm([x, y])
+			self.filter_x.set_measure_cov(np.polyval([0.018, 0.0, 0.0], dist))
+			self.filter_y.set_measure_cov(np.polyval([0.006, 0.0, 0.0], dist))
 		else:
 			x = self.filter_x.x_est
 			y = self.filter_y.x_est
@@ -138,22 +147,32 @@ class Position:
 		return x,y
 
 
+def handle_center_call(req):
+	diff = dwleft.distance_valid() - dwright.distance_valid()
+	dwleft.offset -= diff/2
+	dwright.offset += diff/2
+	rospy.loginfo("Centering to %.2f %.2f", dwleft.offset, dwright.offset)
+	return DWM1000CenterResponse()
+
 if __name__ == "__main__":
-	rospy.init_node('DW1000')
-	dwleft  = DW1000("uwb_dist_left",  0xc2, +0.02)
-	dwright = DW1000("uwb_dist_right", 0xc0, -0.02)
-	dist_l_r = 0.285
+	rospy.init_node('DWM1000', log_level=rospy.DEBUG)
+	dwleft  = DW1000("uwb_dist_left",  0xc2, +0.0)
+	dwright = DW1000("uwb_dist_right", 0xc0, -0.0)
+	dist_l_r = 0.285 # Distance between both DWM1000
 	rate = rospy.Rate(10)
 	pos = Position()
 	tf_broadcaster = tf.broadcaster.TransformBroadcaster()
+	rospy.Service('/DWM1000/center', DWM1000Center, handle_center_call)
 
 	while not rospy.is_shutdown() and dwleft.is_alive() and dwright.is_alive():
 		dist_left = dwleft.distance_valid()
 		dist_right = dwright.distance_valid()
+		x = None
+		y = None
 		if dist_left == None or dist_right == None:
-			print "no valid sensor update"
+			rospy.logerr_throttle(10, "no valid sensor update %r %r" % (dist_left, dist_right))
 			# run kalman prediction only
-			pos.filter(None, None)
+			x,y = pos.filter(None, None)
 		else:
 			dir = "left" if (dist_left < dist_right) else "right"
 
@@ -167,19 +186,18 @@ if __name__ == "__main__":
 				else:
 					dist_left += off/2
 					dist_right -= off/2
-			print "%.2f %.2f %.2f %.2f %s" % (dwleft.distance(), dwright.distance(), dist_left, dist_right, dir)
+			rospy.logdebug("%.2f %.2f %.2f %.2f %s", dwleft.distance(), dwright.distance(), dist_left, dist_right, dir)
 
 			a_r = (-dist_right**2 + dist_left**2 - dist_l_r**2) / (-2*dist_l_r)
 			x = dist_l_r/2 - a_r
 			t = dist_right**2 - a_r**2
 			if t >= 0:
 				y = sqrt(t)
-				print x,y
+				rospy.logdebug("x=%.2f, y=%.2f", x, y)
 				# Rotate 90 deg
 				x, y = (y, -x)
 
 				x, y = pos.filter(x, y)
-				tf_broadcaster.sendTransform((x, y, 0.0), (0, 0, 0, 1), rospy.Time.now(), "uwb_beacon", "base_footprint")
 
 				if VISULAIZE:
 					circle_left = plt.Circle((-dist_l_r/2, 0), dwleft.distance, color='red', fill=False)
@@ -191,6 +209,7 @@ if __name__ == "__main__":
 					plt.show()
 			else:
 				# No current position, still need up update kalman prediction
-				pos.filter(None, None)
+				x, y = pos.filter(None, None)
+		tf_broadcaster.sendTransform((x, y, 0.0), (0, 0, 0, 1), rospy.Time.now(), "uwb_beacon", "base_footprint")
 
 		rate.sleep()