import cv2
import numpy as np
import matplotlib.pyplot as plt
import math
import sys
import time
# based on: https://www.hackster.io/really-bad-idea/autonomous-path-following-car-6c4992#overview
# Throttle
throttlePin = "P9_14"
go_forward = 8.22
dont_move_throttle = 7.75
dont_move_steer = 7.5
# op encode
speed = 0
prev = 0
go_faster_tick = 0 # Do not change this here. Code will set this value after seeing stop sign
# Encoder related variables
speedCheck = 10 # number of frames in between speed adjustment
TARGET = 30 #Target value we want to get from our encoder
SPEED_STEP = 0.02
SPEED_CEIL = 8.5
SPEED_FLOOR = 8.1
# Steering
steeringPin = "P9_16"
left = 9
right = 6
with open("yolov3.txt", 'r') as f:
classes = [line.strip() for line in f.readlines()]
net = cv2.dnn.readNet("yolov3.weights", "yolov3.cfg")
def throttle(duty_cycle):
duty_to_write = 200000 * duty_cycle
duty_to_write = int(duty_to_write)
with open('/dev/bone/pwm/1/a/duty_cycle', 'w') as filetowrite:
filetowrite.write(str(duty_to_write))
def steer(duty_cycle):
duty_to_write = 200000 * duty_cycle
duty_to_write = int(duty_to_write)
with open('/dev/bone/pwm/1/b/duty_cycle', 'w') as filetowrite:
filetowrite.write(str(duty_to_write))
def getRedFloorBoundaries():
"""
Gets the hsv boundaries and success boundaries indicating if the floor is red
:return: [[lower color and success boundaries for red floor], [upper color and success boundaries for red floor]]
"""
return getBoundaries("redboundaries.txt")
def isRedFloorVisible(frame):
"""
Detects whether or not the floor is red
:param frame: Image
:return: [(True is the camera sees a red on the floor, false otherwise), video output]
"""
# print("Checking for floor stop")
boundaries = getRedFloorBoundaries()
return isMostlyColor(frame, boundaries)
def isMostlyColor(image, boundaries):
"""
Detects whether or not the majority of a color on the screen is a particular color
:param image:
:param boundaries: [[color boundaries], [success boundaries]]
:return: boolean if image satisfies provided boundaries, and an image used for debugging
"""
#Convert to HSV color space
hsv_img = cv2.cvtColor(image, cv2.COLOR_BGR2HSV)
#parse out the color boundaries and the success boundaries
color_boundaries = boundaries[0]
percentage = boundaries[1]
lower = np.array(color_boundaries[0])
upper = np.array(color_boundaries[1])
mask = cv2.inRange(hsv_img, lower, upper)
output = cv2.bitwise_and(hsv_img, hsv_img, mask=mask)
#Calculate what percentage of image falls between color boundaries
percentage_detected = np.count_nonzero(mask) * 100 / np.size(mask)
# print("percentage_detected " + str(percentage_detected) + " lower " + str(lower) + " upper " + str(upper))
# If the percentage percentage_detected is betweeen the success boundaries, we return true, otherwise false for result
result = percentage[0] < percentage_detected <= percentage[1]
# if result:
# print(percentage_detected)
return result, output
def getBoundaries(filename):
"""
Reads the boundaries from the file filename
Format:
[0] lower: [H, S, V, lower percentage for classification of success]
[1] upper: [H, S, V, upper percentage for classification of success]
:param filename: file containing boundary information as above
:return: [[lower color and success boundaries], [upper color and success boundaries]]
"""
default_lower_percent = 50
default_upper_percent = 100
with open(filename, "r") as f:
boundaries = f.readlines()
lower_data = [val for val in boundaries[0].split(",")]
upper_data = [val for val in boundaries[1].split(",")]
if len(lower_data) >= 4:
lower_percent = float(lower_data[3])
else:
lower_percent = default_lower_percent
if len(upper_data) >= 4:
upper_percent = float(upper_data[3])
else:
upper_percent = default_upper_percent
lower = [int(x) for x in lower_data[:3]]
upper = [int(x) for x in upper_data[:3]]
boundaries = [lower, upper]
percentages = [lower_percent, upper_percent]
return boundaries, percentages
def initialize_car():
# give 7.5% duty at 50Hz to throttle
#PWM.start(throttlePin, dont_move, frequency=50)
throttle(dont_move_throttle)
# wait for car to be ready
#PWM.start(steeringPin, dont_move, frequency=50)
steer(dont_move_steer)
def stop():
"""
Stops the car
:return: none
"""
#PWM.set_duty_cycle(throttlePin, dont_move)
throttle(dont_move_throttle)
def go():
"""
Sends the car forward at a default PWM
:return: none
"""
#PWM.set_duty_cycle(throttlePin, go_forward)
throttle(go_forward)
def detect_edges(frame):
# filter for blue lane lines
hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)
# cv2.imshow("HSV",hsv)
lower_blue = np.array([90, 120, 0], dtype="uint8")
upper_blue = np.array([150, 255, 255], dtype="uint8")
mask = cv2.inRange(hsv, lower_blue, upper_blue)
# cv2.imshow("mask",mask)
# detect edges
edges = cv2.Canny(mask, 50, 100)
# cv2.imshow("edges",edges)
return edges
def region_of_interest(edges):
height, width = edges.shape
mask = np.zeros_like(edges)
# only focus lower half of the screen
polygon = np.array([[
(0, height),
(0, height / 2),
(width, height / 2),
(width, height),
]], np.int32)
cv2.fillPoly(mask, polygon, 255)
cropped_edges = cv2.bitwise_and(edges, mask)
# cv2.imshow("roi",cropped_edges)
return cropped_edges
def detect_line_segments(cropped_edges):
rho = 1
theta = np.pi / 180
min_threshold = 10
line_segments = cv2.HoughLinesP(cropped_edges, rho, theta, min_threshold,
np.array([]), minLineLength=5, maxLineGap=150)
return line_segments
def average_slope_intercept(frame, line_segments):
lane_lines = []
if line_segments is None:
# print("no line segments detected")
return lane_lines
height, width, _ = frame.shape
left_fit = []
right_fit = []
boundary = 1 / 3
left_region_boundary = width * (1 - boundary)
right_region_boundary = width * boundary
for line_segment in line_segments:
for x1, y1, x2, y2 in line_segment:
if x1 == x2:
# print("skipping vertical lines (slope = infinity")
continue
fit = np.polyfit((x1, x2), (y1, y2), 1)
slope = (y2 - y1) / (x2 - x1)
intercept = y1 - (slope * x1)
if slope < 0:
if x1 < left_region_boundary and x2 < left_region_boundary:
left_fit.append((slope, intercept))
else:
if x1 > right_region_boundary and x2 > right_region_boundary:
right_fit.append((slope, intercept))
left_fit_average = np.average(left_fit, axis=0)
if len(left_fit) > 0:
lane_lines.append(make_points(frame, left_fit_average))
right_fit_average = np.average(right_fit, axis=0)
if len(right_fit) > 0:
lane_lines.append(make_points(frame, right_fit_average))
return lane_lines
def make_points(frame, line):
height, width, _ = frame.shape
slope, intercept = line
y1 = height # bottom of the frame
y2 = int(y1 / 2) # make points from middle of the frame down
if slope == 0:
slope = 0.1
x1 = int((y1 - intercept) / slope)
x2 = int((y2 - intercept) / slope)
return [[x1, y1, x2, y2]]
def display_lines(frame, lines, line_color=(0, 255, 0), line_width=6):
line_image = np.zeros_like(frame)
if lines is not None:
for line in lines:
for x1, y1, x2, y2 in line:
cv2.line(line_image, (x1, y1), (x2, y2), line_color, line_width)
line_image = cv2.addWeighted(frame, 0.8, line_image, 1, 1)
return line_image
def display_heading_line(frame, steering_angle, line_color=(0, 0, 255), line_width=5):
heading_image = np.zeros_like(frame)
height, width, _ = frame.shape
steering_angle_radian = steering_angle / 180.0 * math.pi
x1 = int(width / 2)
y1 = height
x2 = int(x1 - height / 2 / math.tan(steering_angle_radian))
y2 = int(height / 2)
cv2.line(heading_image, (x1, y1), (x2, y2), line_color, line_width)
heading_image = cv2.addWeighted(frame, 0.8, heading_image, 1, 1)
return heading_image
def get_steering_angle(frame, lane_lines):
height, width, _ = frame.shape
if len(lane_lines) == 2:
_, _, left_x2, _ = lane_lines[0][0]
_, _, right_x2, _ = lane_lines[1][0]
mid = int(width / 2)
x_offset = (left_x2 + right_x2) / 2 - mid
y_offset = int(height / 2)
elif len(lane_lines) == 1:
x1, _, x2, _ = lane_lines[0][0]
x_offset = x2 - x1
y_offset = int(height / 2)
elif len(lane_lines) == 0:
x_offset = 0
y_offset = int(height / 2)
angle_to_mid_radian = math.atan(x_offset / y_offset)
angle_to_mid_deg = int(angle_to_mid_radian * 180.0 / math.pi)
steering_angle = angle_to_mid_deg + 90
return steering_angle
def plot_pd(p_vals, d_vals, error, show_img=False):
fig, ax1 = plt.subplots()
t_ax = np.arange(len(p_vals))
ax1.plot(t_ax, p_vals, '-', label="P values")
ax1.plot(t_ax, d_vals, '-', label="D values")
ax2 = ax1.twinx()
ax2.plot(t_ax, error, '--r', label="Error")
ax1.set_xlabel("Frames")
ax1.set_ylabel("PD Value")
ax2.set_ylim(-90, 90)
ax2.set_ylabel("Error Value")
plt.title("PD Values over time")
fig.legend()
fig.tight_layout()
plt.savefig("pd_plot.png")
if show_img:
plt.show()
plt.clf()
def plot_pwm(speed_pwms, turn_pwms, error, show_img=False):
fig, ax1 = plt.subplots()
t_ax = np.arange(len(speed_pwms))
ax1.plot(t_ax, speed_pwms, '-', label="Speed PWM")
ax1.plot(t_ax, turn_pwms, '-', label="Steering PWM")
ax2 = ax1.twinx()
ax2.plot(t_ax, error, '--r', label="Error")
ax1.set_xlabel("Frames")
ax1.set_ylabel("PWM Values")
ax2.set_ylabel("Error Value")
plt.title("PWM Values over time")
fig.legend()
plt.savefig("pwm_plot.png")
if show_img:
plt.show()
plt.clf()
# CYY add for image detect ----- start
def get_output_layers(net):
layer_names = net.getLayerNames()
try:
output_layers = [layer_names[i - 1] for i in net.getUnconnectedOutLayers()]
except:
output_layers = [layer_names[i[0] - 1] for i in net.getUnconnectedOutLayers()]
return output_layers
def checkifStopsign(image, classes, net):
Width = image.shape[1]
Height = image.shape[0]
scale = 0.00392
# classes = None
# with open("yolov3.txt", 'r') as f:
# classes = [line.strip() for line in f.readlines()]
# net = cv2.dnn.readNet("yolov3.weights", "yolov3.cfg")
blob = cv2.dnn.blobFromImage(image, scale, (416,416), (0,0,0), True, crop=False)
net.setInput(blob)
outs = net.forward(get_output_layers(net))
class_ids = []
confidences = []
boxes = []
conf_threshold = 0.5
nms_threshold = 0.4
for out in outs:
for detection in out:
scores = detection[5:]
class_id = np.argmax(scores)
confidence = scores[class_id]
if confidence > 0.5:
center_x = int(detection[0] * Width)
center_y = int(detection[1] * Height)
w = int(detection[2] * Width)
h = int(detection[3] * Height)
x = center_x - w / 2
y = center_y - h / 2
class_ids.append(class_id)
confidences.append(float(confidence))
boxes.append([x, y, w, h])
indices = cv2.dnn.NMSBoxes(boxes, confidences, conf_threshold, nms_threshold)
for i in indices:
print(classes[class_ids[int(i)]])
if classes[class_ids[int(i)]] == "stop sign":
# print("acutal stop sign")
# global signflag
# signflag = True
return True
return False
# CYY add for image detect ----- end
# Max number of loops
max_ticks = 2000
# set up the car throttle and steering PWMs
initialize_car()
# set up video
video = cv2.VideoCapture(2)
video.set(cv2.CAP_PROP_FRAME_WIDTH, 320)
video.set(cv2.CAP_PROP_FRAME_HEIGHT, 240)
# wait for video to load
time.sleep(1)
# PD variables
kp = 0.09
kd = kp*0.1
lastTime = 0
lastError = 0
# counter for number of ticks
counter = 0
# start the engines
go()
# arrays for making the final graphs
p_vals = []
d_vals = []
err_vals = []
speed_pwm = []
steer_pwm = []
current_speed = go_forward
stopSignCheck = 1
sightDebug = False
isStopSignBool = False
isAtRedBox = False
stopSeen = 0
speedCap = False
pause_counter = 0
while counter < max_ticks:
ret, original_frame = video.read()
frame = cv2.resize(original_frame, (160, 120))
if sightDebug:
cv2.imshow("Resized Frame", frame)
# if stopSeen == 0:
# floorGreen, _ = isTrafficGreenLightVisible(frame)
# if floorGreen:
# go()
# else:
# continue
# print("stopSeen: ", stopSeen)
# check for stop sign/traffic light every couple ticks
if ((counter + 1) % stopSignCheck) == 0 and counter > pause_counter:
isStopSignBool, floorSight = isRedFloorVisible(frame)
if isStopSignBool:
print("see red, stop")
stop()
stopSeen += 1
pause_counter = counter + 40
# exit loop on final stop sign
if stopSeen == 3:
print("detected final stop sign, stopping")
break
time.sleep(2)
rett, original_framee = video.read()
framee = cv2.resize(original_framee, (160, 120))
if (checkifStopsign(frame, classes, net)):
print("detected stop sign, stopping")
else:
print("detected red box, stopping")
# if(checkifStopsign(frame, classes, net)):
# print("detected actual stop sign, stopping")
go_forward = 8.22
go()
# process the frame to determine the desired steering angle
# cv2.imshow("original",frame)
edges = detect_edges(frame)
roi = region_of_interest(edges)
line_segments = detect_line_segments(roi)
lane_lines = average_slope_intercept(frame, line_segments)
lane_lines_image = display_lines(frame, lane_lines)
steering_angle = get_steering_angle(frame, lane_lines)
# heading_image = display_heading_line(lane_lines_image,steering_angle)
# cv2.imshow("heading line",heading_image)
# calculate changes for PD
now = time.time()
dt = now - lastTime
if sightDebug:
cv2.imshow("Cropped sight", roi)
deviation = steering_angle - 90
# speed adjustment
if counter % speedCheck == 0:
with open('/sys/module/op_encode/parameters/op_count', 'r') as fileread:
read = int(fileread.read())
speed = read - prev
prev = read
# print(speed)
if speed > TARGET:
go_forward = go_forward - SPEED_STEP
elif speed < TARGET:
go_forward = go_forward + SPEED_STEP
print(go_forward)
# if go_forward > SPEED_CEIL:
# print("=====speed ceil=====")
# go_forward = SPEED_CEIL #limit the highest speed
# elif go_forward < SPEED_FLOOR:
# print("=====speed floor=====")
# go_forward = SPEED_FLOOR
# print(go_forward)
# throttle (go_forward)
# PD Codeint
error = -deviation
base_turn = 7.5
proportional = kp * error
derivative = kd * (error - lastError) / dt
# take values for graphs
p_vals.append(proportional)
d_vals.append(derivative)
err_vals.append(error)
# determine actual turn to do
turn_amt = base_turn + proportional + derivative
# caps turns to make PWM values
if 7.2 < turn_amt < 7.8:
turn_amt = 7.5
elif turn_amt > left:
turn_amt = left
elif turn_amt < right:
turn_amt = right
# turn!
#PWM.set_duty_cycle(steeringPin, turn_amt)
steer(turn_amt)
# take values for graphs
steer_pwm.append(turn_amt)
speed_pwm.append(go_forward)
# update PD values for next loop
lastError = error
lastTime = time.time()
key = cv2.waitKey(1)
if key == 27:
break
counter += 1
# clean up resources
video.release()
cv2.destroyAllWindows()
print("Finishing... ")
steer(dont_move_steer)
throttle(dont_move_throttle)
plot_pd(p_vals, d_vals, err_vals, True)
plot_pwm(speed_pwm, steer_pwm, err_vals, True)
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