robo_explorer: sign when moving backwards

[ros_roboint.git] / scripts / robo_explorer.py

diff --git a/scripts/robo_explorer.py b/scripts/robo_explorer.py
index f39c9c46732ad3bcd71bff05d25c5246b2154094..de755c10c38abbb52fb0261ccd2ed5689282e415 100755 (executable)
--- a/scripts/robo_explorer.py
+++ b/scripts/robo_explorer.py
@@ -2,9 +2,7 @@
 import roslib; roslib.load_manifest('roboint')
 import rospy
 import tf
-import tf.broadcaster
-import tf.transformations
-from math import sin, cos, pi
+from math import *
 from geometry_msgs.msg import Twist, TransformStamped, Point32
 from sensor_msgs.msg import LaserScan
 from nav_msgs.msg import Odometry
@@ -16,7 +14,6 @@ class RoboExplorer:
        def __init__(self):
                rospy.init_node('robo_explorer')
 
-               self.speed = (0, 0)
                self.x = 0
                self.y = 0
                self.alpha = 0
@@ -29,10 +26,10 @@ class RoboExplorer:
 
                # fake laser scan with ultra sonic range finder
                self.enable_ultrasonic_laser = bool(rospy.get_param('~ultrasonic_laser', "True"))
-               # Distance between both wheels in meter (18.8cm)
-               self.wheel_dist = float(rospy.get_param('~wheel_dist', "0.188"))
-               # Size of wheel Diameter in meter (5.1cm) * gear ratio (0.5) = 2.55cm 
-               self.wheel_size = float(rospy.get_param('~wheel_size', "0.0255"))
+               # Distance between both wheels in meter (18.55cm)
+               self.wheel_dist = float(rospy.get_param('~wheel_dist', "0.1855"))
+               # Size of wheel Diameter in meter (5.15cm) * gear ratio (0.5) = 2.575cm 
+               self.wheel_size = float(rospy.get_param('~wheel_size', "0.02575"))
                # Speed to PWM equation gradiant (The m in pwm = speed*m+b)
                self.speed_gradiant = float(rospy.get_param('~speed_gradiant', "64.3"))
                # Speed to PWM equation constant (The b in pwm = speed*m+b)
@@ -63,13 +60,13 @@ class RoboExplorer:
                if self.last_in is not None:
                        in_diff = [abs(a - b) for a, b in zip(in_now, self.last_in)] # get changed inputs
                        # fix in_diff from actual motor direction
-                       if self.speed[0] < 0:
+                       if msg.output[1] > 0: # left reverse
                                in_diff[0] = -in_diff[0]
-                       elif self.speed[0] == 0:
+                       elif msg.output[0] == 0 and msg.output[1] == 0: # left stop
                                in_diff[0] = 0
-                       if self.speed[1] < 0:
+                       if msg.output[3] > 0: # right reverse
                                in_diff[1] = -in_diff[1]
-                       elif self.speed[1] == 0:
+                       elif msg.output[2] == 0 and msg.output[3] == 0: # right stop
                                in_diff[1] = 0
 
                        dist_dir = (in_diff[1] - in_diff[0])*self.wheel_size*pi/8 # steps_changed in different direction => m
@@ -93,8 +90,10 @@ class RoboExplorer:
        def send_odometry(self, msg, current_time):
                # speeds
                dt = (current_time - self.last_time).to_sec()
-               vx = (self.x - self.x_last) / dt
-               vy = (self.y - self.y_last) / dt
+               vx = sqrt((self.x - self.x_last)**2 + (self.y - self.y_last)**2) / dt
+               if (msg.output[0]-msg.output[1] + msg.output[2]-msg.output[3]) < 0:
+                       # moving backward
+                       vx*=-1
                valpha = (self.alpha - self.alpha_last) / dt
                self.x_last = self.x
                self.y_last = self.y
@@ -123,7 +122,7 @@ class RoboExplorer:
                # set the velocity
                odom.child_frame_id = "base_link"
                odom.twist.twist.linear.x = vx
-               odom.twist.twist.linear.y = vy
+               odom.twist.twist.linear.y = 0.0
                odom.twist.twist.angular.z = valpha
 
                # publish the message
@@ -183,16 +182,14 @@ class RoboExplorer:
                #print "Speed wanted: %.2f m/s %.2f rad/s, set: %d %d" % (trans, rot, round(speed_l), round(speed_r))
 
                outmsg = Motor()
-               outmsg.num = 1
+               outmsg.num = 0
                outmsg.speed = round(speed_l)
                self.pub_motor.publish(outmsg)
                
                outmsg = Motor()
-               outmsg.num = 2
+               outmsg.num = 1
                outmsg.speed = round(speed_r)
                self.pub_motor.publish(outmsg)
 
-               self.speed = (speed_l, speed_r)
-
 if __name__ == '__main__':
        RoboExplorer()