+ self.update_odometry(msg, current_time)
+ if (current_time - self.last_time).to_nsec() > 100e6: # send every 100ms
+ self.send_odometry(msg, current_time)
+ self.send_range(msg, current_time)
+ self.last_time = current_time
+
+ def update_odometry(self, msg, current_time):
+ in_now = msg.input[:2]
+ 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 msg.output[1] > 0: # left reverse
+ in_diff[0] = -in_diff[0]
+ elif msg.output[0] == 0 and msg.output[1] == 0: # left stop
+ in_diff[0] = 0
+ if msg.output[3] > 0: # right reverse
+ in_diff[1] = -in_diff[1]
+ 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
+ delta_alpha = dist_dir/self.wheel_dist
+
+ dist = (in_diff[0] + in_diff[1])/2.0 * self.wheel_size*pi/8 # steps_changed same direction => m
+
+ delta_x = cos(self.alpha + delta_alpha/2)*dist
+ delta_y = sin(self.alpha + delta_alpha/2)*dist
+
+ self.alpha += delta_alpha
+ if self.alpha > 2*pi:
+ self.alpha -= 2*pi
+ elif self.alpha < -2*pi:
+ self.alpha += 2*pi
+ self.x += delta_x
+ self.y += delta_y