地图

基础知识

• 地图的数据按照行优先的顺序，从栅格矩阵的（0,0）位置开始排列
• 栅格里的障碍物占据值范围是从0到100，如果栅格里的障碍物状况位置，则栅格数值为-1

发布自定义地图

注意事项

• 依赖项里添加nav_msgs

代码示例

C++

#include <ros/ros.h>
#include <nav_msgs/OccupancyGrid.h>

int main(int argc, char *argv[])
{
    ros::init(argc, argv, "map_pub_node");
    ros::NodeHandle nh;
    ros::Publisher pub = nh.advertise<nav_msgs::OccupancyGrid>("/map",10);
    
    ros::Rate r(1);
    while (ros::ok()){
        nav_msgs::OccupancyGrid msg;
        msg.header.frame_id = "map";
        msg.header.stamp = ros::Time::now();

        msg.info.origin.position.x = 1;
        msg.info.origin.position.y = 1;
        msg.info.resolution = 1.0;
        msg.info.width = 4;
        msg.info.height = 2;

        msg.data.resize(4*2);
        msg.data[0] = 100;
        msg.data[1] = 100;
        msg.data[2] = 0;
        msg.data[3] = -1;

        pub.publish(msg);
        r.sleep();

    }
    

    return 0;
}

Python

#!/usr/bin/env python3
#coding=utf-8

import rospy
from nav_msgs.msg import OccupancyGrid

if __name__ == "__main__":
    rospy.init_node("map_pub_node")
    pub = rospy.Publisher("/map", OccupancyGrid, queue_size=10)

    rate = rospy.Rate(1)
    while not rospy.is_shutdown():
        msg = OccupancyGrid()
        msg.header.frame_id = "map"
        msg.header.stamp = rospy.Time.now()

        msg.info.origin.position.x = 0
        msg.info.origin.position.y = 0
        msg.info.resolution = 1.0
        msg.info.width = 4 
        msg.info.height = 2


        msg.data = [0]*4*2
        msg.data[0] = 100
        msg.data[1] = 100
        msg.data[2] = 0
        msg.data[3] = -1

        pub.publish(msg)
        rate.sleep()

map_server

保存地图

rosrun map_server map_saver [--occ <threshold_occupied>] [--free <threshold_free>] [-f <mapname>] map:=/your/costmap/topic

rosrun map_sever map_saver -f 文件名

加载地图

rosrun rosrun map_server map_server mymap.yaml

代价地图