Hi everyone, I am new here and I hope that I didn’t skip any step in order to public a topic 
I built a drone and a would like to use the offboard mode in order to program my own code.
Yesterday i used this code and when the drone took off from the ground didn’t reach 0.30 m but continued to rise until it hit the ceiling (2.80m). i don’t understand why this error. i attached my code here.
#include <ros/ros.h>
#include <geometry_msgs/PoseStamped.h>
#include <mavros_msgs/CommandBool.h>
#include <mavros_msgs/CommandTOL.h>
#include <mavros_msgs/SetMode.h>
#include <mavros_msgs/State.h>
#define FLIGHT_ALTITUDE 0.3f
mavros_msgs::State current_state;
void state_cb(const mavros_msgs::State::ConstPtr& msg){
current_state = *msg;
}
int main(int argc, char **argv)
{
ros::init(argc, argv, “off_square”);
ros::NodeHandle nh;
ros::Subscriber state_sub = nh.subscribe<mavros_msgs::State>
("mavros/state", 10, state_cb);
ros::Publisher local_pos_pub = nh.advertise<geometry_msgs::PoseStamped>
("mavros/setpoint_position/local", 10);
ros::ServiceClient arming_client = nh.serviceClient<mavros_msgs::CommandBool>
("mavros/cmd/arming");
ros::ServiceClient land_client = nh.serviceClient<mavros_msgs::CommandTOL>
("mavros/cmd/land");
ros::ServiceClient set_mode_client = nh.serviceClient<mavros_msgs::SetMode>
("mavros/set_mode");
//the setpoint publishing rate MUST be faster than 2Hz
ros::Rate rate(20.0);
// wait for FCU connection
while(ros::ok() && current_state.connected){
ros::spinOnce();
rate.sleep();
ROS_INFO("connecting to FCT...");
}
geometry_msgs::PoseStamped pose;
pose.pose.position.x = 0;
pose.pose.position.y = 0;
pose.pose.position.z = FLIGHT_ALTITUDE;
//send a few setpoints before starting
for(int i = 100; ros::ok() && i > 0; --i){
local_pos_pub.publish(pose);
ros::spinOnce();
rate.sleep();
}
mavros_msgs::SetMode offb_set_mode;
offb_set_mode.request.custom_mode = "OFFBOARD";
mavros_msgs::CommandBool arm_cmd;
arm_cmd.request.value = true;
mavros_msgs::CommandTOL land_cmd;
land_cmd.request.yaw = 0;
land_cmd.request.latitude = 0;
land_cmd.request.longitude = 0;
land_cmd.request.altitude = 0;
ros::Time last_request = ros::Time::now();
// change to offboard mode and arm
while(ros::ok() && !current_state.armed){
if( current_state.mode != "OFFBOARD" &&
(ros::Time::now() - last_request > ros::Duration(5.0))){
if( set_mode_client.call(offb_set_mode) &&
offb_set_mode.response.mode_sent){
ROS_INFO("Offboard enabled");
}
last_request = ros::Time::now();
} else {
if( !current_state.armed &&
(ros::Time::now() - last_request > ros::Duration(5.0))){
if( arming_client.call(arm_cmd) &&
arm_cmd.response.success){
ROS_INFO("Vehicle armed");
}
last_request = ros::Time::now();
}
}
local_pos_pub.publish(pose);
ros::spinOnce();
rate.sleep();
}
// go to the first waypoint
pose.pose.position.x = 0;
pose.pose.position.y = 0;
pose.pose.position.z = FLIGHT_ALTITUDE;
ROS_INFO("going to the first way point");
for(int i = 0; ros::ok() && i < 10*20; ++i){
local_pos_pub.publish(pose);
ros::spinOnce();
rate.sleep();
}
ROS_INFO("first way point finished!");
// go to the second waypoint
pose.pose.position.x = 0;
pose.pose.position.y = 0.3;
pose.pose.position.z = FLIGHT_ALTITUDE;
//send setpoints for 10 seconds
ROS_INFO("going to second way point");
for(int i = 0; ros::ok() && i < 10*20; ++i){
local_pos_pub.publish(pose);
ros::spinOnce();
rate.sleep();
}
ROS_INFO("second way point finished!");
// go to the third waypoint
pose.pose.position.x = 0.3;
pose.pose.position.y = 0.3;
pose.pose.position.z = FLIGHT_ALTITUDE;
//send setpoints for 10 seconds
ROS_INFO("going to third way point");
for(int i = 0; ros::ok() && i < 10*20; ++i){
local_pos_pub.publish(pose);
ros::spinOnce();
rate.sleep();
}
ROS_INFO("third way point finished!");
// go to the forth waypoint
pose.pose.position.x = 0.3;
pose.pose.position.y = 0;
pose.pose.position.z = FLIGHT_ALTITUDE;
//send setpoints for 10 seconds
ROS_INFO("going to forth way point");
for(int i = 0; ros::ok() && i < 10*20; ++i){
local_pos_pub.publish(pose);
ros::spinOnce();
rate.sleep();
}
ROS_INFO("forth way point finished!");
pose.pose.position.x = 0;
pose.pose.position.y = 0;
pose.pose.position.z = FLIGHT_ALTITUDE;
ROS_INFO("going back to the first point!");
//send setpoints for 10 seconds
for(int i = 0; ros::ok() && i < 10*20; ++i){
local_pos_pub.publish(pose);
ros::spinOnce();
rate.sleep();
}
ROS_INFO("tring to land");
while (!(land_client.call(land_cmd) &&
land_cmd.response.success)){
//local_pos_pub.publish(pose);
ROS_INFO("tring to land");
ros::spinOnce();
rate.sleep();
}
return 0;
}