Problems with controlling quadrotor in guided mode

Hi all,

I’m trying to control a quadrotor with Pixhawk Cube (Ardupilot installed) using a companion PC running ROS.

The quadrotor flies without any issues in ‘Lotier mode’, and using the companion PC and ROS, I can set the control mode to ‘guided mode’, take off, and land.

However, I’m having trouble moving the quad to the desired location.

Right now, I’m trying to move the quad toward East by 1 m.

I setup my quad so that it points toward East, and I send the command for it to take off, move in x-direction by 1 m, and land (I believe that in UTM, x is Easting).

The problem is, sometimes the quad moves forward and lands. Other times, it moves backward and lands, although the the same ROS script is used and the quad is positioned at exactly the same position and orientation.

I’m sending command via mavros/setpoint_position/local by updating its x, y and z (x = 1, y = 0, z = desired height).

I first thought that the problem is due to the position tracking errors with the GPS, but the motion by the quad seems unlikely that it is caused by the GPS errors.

Has anyone experienced similar problems? Any help would be greatly appreciated.