+#include <ros/ros.h>
+#include <image_transport/image_transport.h>
+#include <cv_bridge/cv_bridge.h>
+#include <sensor_msgs/image_encodings.h>
+#include <opencv2/imgproc/imgproc.hpp>
+#include <opencv2/highgui/highgui.hpp>
+#include <ros/package.h>
+#include <dynamic_reconfigure/server.h>
+#include <wild_thumper/PathFollowingConfig.h>
+#include <geometry_msgs/Twist.h>
+
+using namespace cv;
+
+static const std::string OPENCV_WINDOW = "Image window";
+static const Scalar& red = CV_RGB(255,0,0);
+static const Scalar& orange = CV_RGB(255,165,0);
+static const Scalar& green = CV_RGB(0,255,0);
+static const Scalar& blue = CV_RGB(0,0,255);
+static const Scalar& purple = CV_RGB(128,0,128);
+
+class PathFollower
+{
+ ros::NodeHandle nh;
+ image_transport::ImageTransport it;
+ image_transport::Subscriber image_sub;
+ ros::Publisher cmdvel_pub;
+ int roi_x;
+ int roi_y;
+ int binary_threshold;
+ int ht_min_points;
+ int roi_width, roi_height;
+ double x_px_per_cm, y_px_per_cm, y_offset_cm;
+ int x_offset_px;
+ float lap_x_cm, lap_y_cm;
+ float road_distance_cm, lad_cm;
+ int img_vsize, img_hsize;
+ double axial_dist_cm;
+ float speed_m_s;
+ Mat transformation_matrix;
+ dynamic_reconfigure::Server<wild_thumper::PathFollowingConfig> server;
+
+ public:
+ PathFollower() : it(nh)
+ {
+ ros::NodeHandle pnh("~");
+ FileStorage fs(ros::package::getPath("wild_thumper") + "/cfg/transformation_matrix.yml", FileStorage::READ);
+ dynamic_reconfigure::Server<wild_thumper::PathFollowingConfig>::CallbackType f;
+
+ fs["transformation_matrix"] >> transformation_matrix;
+ pnh.param("roi_x_init", roi_x, 280);
+ pnh.param("roi_width", roi_width, 50);
+ pnh.param("roi_height", roi_height, 50);
+ pnh.param("x_px_per_cm", x_px_per_cm, 2.778);
+ pnh.param("y_px_per_cm", y_px_per_cm, 2.778);
+ pnh.param("y_offset_cm", y_offset_cm, 23.5);
+ pnh.param("img_vsize", img_vsize, 480);
+ pnh.param("img_hsize", img_hsize, 640);
+ pnh.param("x_offset_px", x_offset_px, 65);
+ pnh.param("axial_dist_cm", axial_dist_cm, 25.4);
+ lap_x_cm=0;
+ lap_y_cm=0;
+ f = boost::bind(&PathFollower::dynreconf_callback, this, _1, _2);
+ server.setCallback(f);
+
+ // Subscrive to input video feed and publish output video feed
+ image_sub = it.subscribe("/camera/rgb/image_raw", 1, &PathFollower::imageCb, this);
+ cmdvel_pub = nh.advertise<geometry_msgs::Twist>("/cmd_vel", 10);
+
+ fs.release();
+
+ cv::namedWindow(OPENCV_WINDOW);
+ }
+
+ ~PathFollower()
+ {
+ cv::destroyWindow(OPENCV_WINDOW);
+ }
+
+ int pathfinder(cv::Mat &frame, float &r, float &phi)
+ {
+ cv::vector<cv::Vec2f> lines;
+ cv::warpPerspective(frame, frame, transformation_matrix, frame.size(), INTER_LINEAR);
+ Mat roi(frame, Rect(roi_x, roi_y, roi_width, roi_height));
+
+ cv::threshold(roi, roi, binary_threshold, 255, CV_THRESH_BINARY);
+ cv::erode(roi, roi, cv::Mat(), cv::Point(-1, -1), 1);
+ cv::HoughLines(roi, lines, 1, CV_PI/90, ht_min_points, 0, 0);
+
+ if (lines.size() > 0) { // use first result
+ r = lines[0][0];
+ phi = lines[0][1];
+
+ if (phi > CV_PI/2) { // keep in +-90°
+ phi = phi-CV_PI;
+ r = -r;
+ }
+
+ // Update dynamic ROI
+ roi_x = roi_x - roi_width/2 + r;
+ }
+
+ return lines.size();
+ }
+
+ void calc_lap(float r, float phi) {
+ float roi_x_h, lap_x_h, lap_y_h;
+
+ // 1. rotate ROI by phi (in Hilfskoordinatensystem)
+ roi_x_h = (cos(-phi)*px_to_cm_x(roi_x) + -sin(-phi)*px_to_cm_y(roi_y));
+
+ // 2. lap_h
+ lap_x_h = roi_x_h + r - road_distance_cm;
+ // lap_x_h
+ lap_y_h = sqrt(lad_cm*lad_cm - lap_x_h*lap_x_h);
+
+ // 3. rotate LAP back by phi
+ lap_x_cm = (cos(phi)*lap_x_h + -sin(phi)*lap_y_h);
+ lap_y_cm = (sin(phi)*lap_x_h + cos(phi)*lap_y_h);
+ }
+
+ float pure_pursuit(float r, float phi) {
+ calc_lap(r, phi);
+
+ return -atan((2*lap_x_cm*axial_dist_cm)/((float)lad_cm*lad_cm));
+ }
+
+ void imageCb(const sensor_msgs::ImageConstPtr& msg)
+ {
+ cv_bridge::CvImagePtr cv_ptr;
+ cv::Mat cimg;
+ float r, phi;
+ int htvalid;
+ float alpha;
+
+ try
+ {
+ cv_ptr = cv_bridge::toCvCopy(msg, sensor_msgs::image_encodings::MONO8);
+ }
+ catch (cv_bridge::Exception& e)
+ {
+ ROS_ERROR("cv_bridge exception: %s", e.what());
+ return;
+ }
+ htvalid = pathfinder(cv_ptr->image, r, phi);
+
+ cv::cvtColor(cv_ptr->image, cimg, CV_GRAY2RGB);
+ cv::rectangle(cimg, cv::Point(roi_x, roi_y), cv::Point(roi_x+roi_width, roi_y+roi_height), red, 1);
+
+ // grid
+ cv::line(cimg, Point(0, cm_to_px_y(50)), Point(img_hsize, cm_to_px_y(50)), blue, 1);
+ putText(cimg, " 50cm", Point(img_hsize-60, cm_to_px_y(50)+15), FONT_HERSHEY_PLAIN, 1.0, blue);
+ cv::line(cimg, Point(0, cm_to_px_y(60)), Point(img_hsize, cm_to_px_y(60)), blue, 1);
+ putText(cimg, " 60cm", Point(img_hsize-60, cm_to_px_y(60)+15), FONT_HERSHEY_PLAIN, 1.0, blue);
+ cv::line(cimg, Point(0, cm_to_px_y(70)), Point(img_hsize, cm_to_px_y(70)), blue, 1);
+ putText(cimg, " 70cm", Point(img_hsize-60, cm_to_px_y(70)+15), FONT_HERSHEY_PLAIN, 1.0, blue);
+ cv::line(cimg, Point(0, cm_to_px_y(80)), Point(img_hsize, cm_to_px_y(80)), blue, 1);
+ putText(cimg, " 80cm", Point(img_hsize-60, cm_to_px_y(80)+15), FONT_HERSHEY_PLAIN, 1.0, blue);
+ cv::line(cimg, Point(0, cm_to_px_y(100)), Point(img_hsize, cm_to_px_y(100)), blue, 1);
+ putText(cimg, "100cm", Point(img_hsize-60, cm_to_px_y(100)+15), FONT_HERSHEY_PLAIN, 1.0, blue);
+ // distance
+ cv::line(cimg, Point(cm_to_px_x(road_distance_cm), 0), Point(cm_to_px_x(road_distance_cm), img_vsize), purple, 1);
+
+ if (htvalid) {
+ double a = cos(phi), b = sin(phi);
+ double x0 = a*r + roi_x;
+ double y0 = b*r + roi_y;
+ Point pt1, pt2;
+ pt1.y = 0;
+ pt1.x = r/(cos(phi));
+ pt2.y = roi_height;
+ pt2.x = (r - pt2.y*sin(phi)) / (cos(phi));
+ cv::line(cimg, Point(roi_x, roi_y) + pt1, Point(roi_x, roi_y) + pt2, orange, 2);
+
+ alpha = pure_pursuit(px_to_cm_x(roi_x + r), phi);
+ ROS_INFO("alpha=%.2f deg", alpha*180/M_PI);
+ if (speed_m_s > 0) {
+ set_vel(speed_m_s, alpha);
+ }
+ }
+
+ cv::circle(cimg, Point(cm_to_px_x(lap_x_cm), cm_to_px_y(lap_y_cm)), 5, green, -1);
+
+ // Update GUI Window
+ cv::imshow(OPENCV_WINDOW, cimg);
+ cv::waitKey(3);
+ }
+
+ int cm_to_px_x(float cm) {
+ return round(cm * x_px_per_cm + img_hsize/2 - x_offset_px);
+ }
+
+ double px_to_cm_x(int px) {
+ return (px-img_hsize/2+x_offset_px) / x_px_per_cm;
+ }
+
+ int cm_to_px_y(float cm) {
+ return round((-cm+y_offset_cm) * y_px_per_cm + img_vsize);
+ }
+
+ double px_to_cm_y(int px) {
+ return (img_vsize-px) / y_px_per_cm + y_offset_cm;
+ }
+
+ void dynreconf_callback(wild_thumper::PathFollowingConfig &config, uint32_t level) {
+ int px;
+
+ binary_threshold = config.binary_threshold;
+ ht_min_points = config.ht_min_points;
+ px = cm_to_px_y(config.roi_y);
+ if (px > 0 && px < img_vsize - roi_height) roi_y = px;
+ else ROS_ERROR("Bad roi_y position %.2fcm", roi_y);
+ road_distance_cm = config.road_distance_cm;
+ lad_cm = config.lad_cm;
+ speed_m_s = config.speed_m_s;
+ }
+
+ void set_vel(float speed, float alpha) {
+ geometry_msgs::Twist msg;
+
+ msg.linear.x = speed;
+ msg.angular.z = alpha;
+
+ cmdvel_pub.publish(msg);
+ }
+};
+
+int main(int argc, char** argv)
+{
+ ros::init(argc, argv, "path_following");
+
+ PathFollower ic;
+ ros::spin();
+ return 0;
+}
projects / ros_wild_thumper.git / commitdiff
