# waypointTrajectory orientation is not matching

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Ravindra on 20 Oct 2020
Edited: Ravindra on 22 Oct 2020
Two trajectories were generated considering the monocular visual-inertial example https://de.mathworks.com/help/fusion/ug/visual-inertial-odometry-using-synthetic-data.html
The first trajectory is same as in example
% track without orientation angles
traj = waypointTrajectory(wayPoints, 'TimeOfArrival', t, ...
'Velocities', velocities, 'SampleRate', sampleRate);
The second trajectory the orientation is added to the same values in example
Ori = [0 0 0;...
0 0 0;...
90 0 0;...
90 0 0;...
0 0 0;...
0 0 0;...
0 0 0;...
90 0 0;...
180 0 0;...
180 0 0;...
180 0 0];
% track with orientation angles
traj_Ori= waypointTrajectory(wayPoints, ...
'TimeOfArrival',t, ...
'Orientation',quaternion(Ori,'eulerd','ZYX','frame'), ...
'Velocities', velocities,'SampleRate',sampleRate);
Later both trajectories were plotted together to check if they have same values. The position is exactly matching but the orientation-axis doesn't.
The Roll, Pitch and Yaw angles are following:
What is the correct way to generate the trajectory with given orientation angels?

Brian Fanous on 21 Oct 2020
Hi Ravindra
In the first example you are not specifying the Orienation so the waypointTrajectory infers that the vehicle is pointed in the direction of travel. In the second example you are explicitly specifying the orientation so the waypointTrajectory uses the Ori array. Try:
help waypointTrajectory/Orientation
Best,
Brian
Ravindra on 22 Oct 2020
Thanks that explains the different orientations for both trajectories.
But in case I would like to switch the axis of the vehicle. I mean by default the waypointTrajectory vehicle's x-axis points to front, y-axis to the left and z-axis towards up.
If I would like to calculate a trajectory by switching axis as shown in figure below. How should I proceed?
In this case I guess we should provide all the three angles!