Gezebo_precision_landing.py error


#1

Can’t detect Aruco markers.
And land around the marker.
Please check below

=========================
#!/usr/bin/env python

######IMPORTS######

import rospy
from sensor_msgs.msg import Image
import cv2
import cv2.aruco as aruco
import sys
import time
import math
import numpy as np
import ros_numpy as rnp
from dronekit import connect, VehicleMode, LocationGlobalRelative, LocationGlobal
from pymavlink import mavutil
from array import array

#####VARIABLES####

vehicle = connect(‘udp:127.0.0.1:14551’,wait_ready=True)
vehicle.parameters[‘PLND_ENABLED’]=1
vehicle.parameters[‘PLND_TYPE’]=1
vehicle.parameters[‘PLND_EST_TYPE’]=0
vehicle.parameters[‘LAND_SPEED’]=30 ##CM/S

velocity=.5 #m/s
takeoff_height=4 #m m0.5],[0.0, 530.8269276712998, 240.5],[0.0, 0.0, 1.0]]

newing_pub = rospy.Publisher(‘camera/color/image_new’, Image, queue_size=10)

id_to_find = 72 ##aruco
marker_size = 20 ## CM

aruco_dict = aruco.getPredefinedDictionary(aruco.DICT_ARUCO_ORIGINAL)
parameters = aruco.DetectorParameters_create()

horizontal_res = 640
vertical_res = 480

horizontal_fov = 62.2*(math.pi/180) ##62.2 for picam v2, 53.5 for v1
vertical_fov = 48.8*(math.pi/180) ##48.8 for v2, 41.41 for v1

found_count = 0
notfound_count = 0

#################[CAMERA_INTRINSICS]#################

dist_coeff = [0.0, 0.0, 0.0, 0.0, 0.0]
camera_matrix = [[530.8269276712998, 0.0, 320.5],[0.0, 530.8269276712998, 240.5],[0.0, 0.0, 1.0]]
np_camera_matrix = np.array(camera_matrix)
np_dist_coeff = np.array(dist_coeff)

time_last = 0
time_to_wait = .1 ##100 ms
#####################FUNCTION########################
def arm_and_takeoff(targetHeight):
while vehicle.is_armable !=True:
print ‘Waiting for vehicle to become armable’
time.sleep(1)
print ‘vehicle is now armable’

vehicle.mode = VehicleMode('GUIDED')

while vehicle.mode !='GUIDED':
    print 'Waiting for drone to ender GUIDED flight mode'
    time.sleep(1)
print 'Vehicle now in GUIDED mode. Have Fun'

vehicle.armed = True
while vehicle.armed ==False:
    print 'Waiting for vehicle to become armed.'
    time.sleep(1)
print 'Look out! Virtual props are spinning'

vehicle.simple_takeoff(targetHeight) ##meters

while True:
     print('Current Altitude: %d'%vehicle.location.global_relative_frame.alt)
     if vehicle.location.global_relative_frame.alt >=.95*targetHeight:
         break
     time.sleep(1)
print 'Target altitude reached!'

return None

###SEND VELOCITY COMMAND TO DRONE###

def send_local_ned_velocity(vx,vy,vz):
msg = vehicle.message_factory.set_position_target_local_ned_encode(
0,
0, 0,
mavutil.mavlink.MAV_FRAME_BODY_OFFSET_NED,
0b0000111111000111,
0, 0, 0,
vx, vy, vz,
0,0,0,0,0)
vehicle.send_mavlink(msg)
vehicle.flush()

def send_land_message(x,y):
msg = vehicle.message_factory.landing_target_encode(
0,
0,
mavutil.mavlink.MAV_FRAME_BODY_OFFSET_NED,
x,
y,
0,
0,
0,)
vehicle.send_mavlink(msg)
vehicle.flush()

def msg_receiver(message):
global notfound_count, found_count, time_last, time_to_wait, id_to_find

if time.time() - time_last > time_to_wait:
    np_data = rnp.numpify(message) ##Deserialize image data into array
    gray_img = cv2.cvtColor(np_data, cv2.COLOR_BGR2GRAY)

    ids = ''
    #ids=[129,72]
    (corners, ids, rejected) = aruco.detectMarkers(image=gray_img, dictionary=aruco_dict, parameters=parameters)

    try:
        if ids is not None:
            if ids[0] == id_to_find:
                ret = aruco.estimatePoseSingleMarkers(corners,marker_size, cameraMatrix=np_camera_matrix, distCoeffs=np_dist_coeff)
                (rvec,tvec) = (ret[0][0,0,:],ret[1][0,0,:])
                x='{:.2f}'.format(tvec[0]) ###Xerror/distance between camera and aruco in cm
                y='{:.2f}'.format(tvec[1]) ###Yerror/distance between camera and aruco in cm
                z='{:.2f}'.format(tvec[2]) ###Zerror/distance between camera and aruco in cm

                x_sum=0
                y_sum=0

                x_sum = corners[0][0][0][0] + corners[0][0][1][0] + corners[0][0][2][0] + corners[0][0][3][0]
                y_sum = corners[0][0][0][1] + corners[0][0][1][1] + corners[0][0][2][1] + corners[0][0][3][1]

                x_avg = x_sum / 4
                y_avg = y_sum / 4

                x_ang = (x_avg - horizontal_res*.5)*horizontal_fov/horizontal_res
                y_ang = (y_avg - vertical_res*.5)*vertical_fov/vertical_res

                if vehicle.mode !='LAND':
                    vehicle.mode = VehicleMode('LAND')
                    while vehicle.mode !='LAND':
                        time.sleep(1)
                    print 'Vehicle in LAND mode'
                    send_land_message(x_ang,y_ang)
                else:
                    send_land_message(x_ang, y_ang)

                marker_position = 'MARKER POSITION: x='+x+' y='+y+' z='+z

                aruco.drawDetectedMarkers(np_data,corners)
                aruco.drawAxis(np_data,np_camera_matrix,np_dist_coeff,rvec,tvec,10)
                ##puttText(image, text_to_draw,position,font_face,fontScale,color,thickness)
                cv2.putText(np_data,marker_position,(10,50),0,.7,(255,0,0),thickness=2)
                print(marker_position)
                print ('FOUND COUNT: '+str(found_count)+ 'NOTFOUND COUNT: '+str(notfound_count))

                found_count = found_count + 1
            else:
                notfound_count=notfound_count+1
        else:
                notfound_count=notfound_count+1
    except Exception as e:
            print 'Target likely not found'
            print e
            notfound_count=notfound_count+1
    new_msg = rnp.msgify(Image, np_data,encoding='rgb8')
    newing_pub.publish(new_msg)
    time_last = time.time()
else:
        return None

def subscriber():
rospy.init_node(‘drone_node’,anonymous=False)
sub = rospy.Subscriber(’/camera/color/image_raw’, Image, msg_receiver)
rospy.spin()

if name==‘main’:
try:
arm_and_takeoff(takeoff_height)
time.sleep(1)
send_local_ned_velocity(velocity,0,0)
time.sleep(1)
subscriber()
except rospy.ROSInterruptException:
pass


#2

typo, should be ‘newimg_pub’
image


#3

thank you so much.
I corrected it.
However, it does not land on the marker.
What should I do?

image


#4

I found still more errors in your code. These were remnants from track_aruco.py.

image

I strongly recommend trouble-shooting code that you can do yourself by comparing it with the course videos or the .ova files provided. I hope this helps but if not let me know.