# Questions tagged [quaternion]

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### joints gimble lock issue

I am trying to create a mecanum wheels by attaching each pinion as a joint to a wheel in URDF. For this, I have rotated the pinion 90 degree(pitch) and 45 degree(yaw). When i am doing these rotations ...
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1 vote
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### How to compute quaternion or Roll Pitch Yaw from a directional vector?

I am trying to get a sensor attached to the end of a robot arm to point at a specific Point of Interest. I know the XYZ position of both the POI and the target pose of the sensor, and I am able to ...
42 views

### How to give Moveit! local orientation goal to my end effector, but global position?

As the title says, how to give a local orientation to my end effector, but global position? Basically this would mimic the goal orb in RVIZ, where you can drag it around to give global position, but ...
310 views

### How to get the world coordinates with position and orientation in ROS 2 Humble

I am using ROS 2 Humble. A person is supposed to take a photo of an AR marker with a camera. Inside the system, we can obtain the relative coordinates, position (x, y, z), and rotation, orientation (x,...
1 vote
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### Customize SLERP used in MoveIt motion planning

I am currently working on a project utilizing ROS Noetic and MoveIt for robotic arm path planning. I have a robot arm that has to pick up items from between shelves on its left and right side. However,...
56 views

### ROS custom msg to be used in an ESP32 microcontroller using Platformio

I'm trying to publish an array of quaternions to a single topic on ROS noetic. For that I created a new message type following the tutorial: ...
22 views

### Does the Factored Quaternion Algorithm Account for Declination?

Looking at the documentation for the Factored Quaternion Algorithm (FQA). In section 2 they define NED as the traditional Earth's fixed coordinate system, thereby referring to 'true' north. However, ...
104 views

### How to use quaternions in ROS2

I have to use some sort of transformations to generate velocity of a model using global coordinates. This code is for making the model go to specific locations (goals). the problem i am facing is that ...
75 views

### How to convert accel data to quaternion?

To ask my question better, let's assume that I have created 2 different accel data: timestamp accel_x (m/s^2) accel_y (m/s^2) accel_z (m/s^2) 1 0.0009314967509892153 0.004056761742037966 -9....
63 views

### Finding shoulder joint orientation

Ok so I have been trying to find out shoulder joint angles from a kinect RGB-D camera.My end goal is to acquire these angles to feed them to a robotic arm (7DoF - 3 shoudler 1 elbow 3 wrist) and ...
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### Visualize object orientation using IMU

Hello my question might sound a little naive I know. But, you know how tedious and confusing quaternions might be. I have an OAK-D camera with it's model in stl format have a URDF provided with all ...
45 views

### UR5 how to convert axis angles to quaternions

Hi, We have a UR5 robotic arm. We use Moveit move_group_interface to send simple pose and joint-space goals to this arm. In ...
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### Equivalent of checking quaternion is valid in tf2

Is there an equivalent function to assertQuaternionValid() in tf2? I suppose I could just re-implement the source code for the function using tf2 equivalents? http:/...
236 views

### MSG to TF : Quaternion Not Properly Normalized

Thank you for clicking, hello, I'm ros begginer. I am currently using IMU for Slam mapping. But I get the ERR MSG(MSG to TF : Quaternion Not Properly Normalized). What should I do?? ...
23 views

### Possible error in 'Quaternions' tutorial

Hi, I tried transforming roll, pitch, yaw angles to a quaternion in python following this tutorial (http://wiki.ros.org/tf2/Tutorials/Quaternions). In subtopic 3 "Think in RPY then convert to ...
65 views

### How to derive a pose quaternion from orientation vectors with tf2

I am trying to calculate the pose of an object using tf2. I know the X', Y', Z' vectors defining the orientation of the object - ie. the principle axes of the target frame, expressed in the origin ...
8 views

### Quaternion wrong orientation

I have a binpick application with robot arm and a fixed camera. The camera does it's vision stuff and sends the robot pickpose as a quaternion to the robot, This is done using a static tf between the ...
47 views

### Default transform direction if tf2?

I'm instantiating a tf2::Quaternion from a custom quaternion (scalar first) defined as the rotation of a vector from inertial to body coordinate system. In the next step I'm instantiating a tf2::...
434 views

### Converting image pixel coordinates 2D(X, Y) to 3D world coordinate(Quaternion)

Hi there, I want to obtain quaternion from x,y,z(depth camera) position. I am new to ros, and I am using Intel real sense. Things Done: I have integrated yolov5 with ros, and I am obtaining the ...
95 views

### Converting cv::Mat rotation matrix to quaternion

Is there a way to convert a cv::Mat rotation matrix to a quaternion? Originally posted by EDU4RDO-SH on ROS Answers with karma: 52 on 2020-07-28 Post score: 1 Original comments Comment by ...
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### Compute quaternion from angular velocity Twist

Hi, I'm using ROS melodic with kitti bag file. I'm running Ubuntu 18.04 on i7 , with kernel 5.3.0-42-generic. I get the odometry of a Kitti bag file with viso2_ros. I want to predict the poses of the ...
11 views

### Converting vector to orientation in sensor_msgs/Imu

I'm using the Lego Control+ Technic Hub as an IMU using the node-poweredup library. I am getting the imu data from the hub into ROS just fine but I am having trouble knowing how to correctly publish ...
37 views

### Create quaternion from euler in arduino

HI How to create a quaternion from Euler angles in arduino? In python it is possible to use this function: ...
25 views

### Orienting the robot properly

I'm trying to position my robot in a particular way after it reaches a particular checkpoint. ...
204 views

### how to get rotation matrix from quaternion in python

I can see tf.transformations have a matrix to quaternion function, but is there a way to do the opposite in python? Originally posted by mugetsu on ROS Answers with karma: 195 on 2019-05-30 Post ...
3 views

### why the robot position coordinate change a lot when doing rotation?

Dear all, Sorry forget my silly question, here I follow some tutorial code to write a test code to control TB3 burger to move a triangle shape. Below are part of code that to obtain the current ...
10 views

### Combine two parent-child transformations for common link

I am trying to connect two tf trees via a known link by following the advice from @tfoote here. One link belongs to the robot tf tree and the other belongs to a camera tf tree that is not part of the ...
176 views

### How to calculate the difference between two geometry_msgs::Pose

I have two geometry_msgs::Pose structure p1 and p2. Each of them contains a geometry_msgs::Point and geometry_msgs::Quaternion. I would like to calculate the different between the two poses. I know ...
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### Calculate picking pose from mesh origin pose (using tf?)

I would like to pick and place multiple times an object I have in the collision world. The object gets moved in different states, and at the moment I don't have cameras on the scene so I can't infer ...
31 views

### Static tf2 transform returns correct position but opposite quaternion

Trying to read the state of my robotic arm, I found that the manufacturer provided transforms for everything up to the flange but not to the center of the closed fingers in the end effector. In the ...
6 views

### normal/orthogonal orientation to a surface

Hello! (This can be a bit noob question, but im confused, so i ask) Lets say I have a surface, a wall, described by YZ points of the world coordinate frame. I want my robot EEF to go to a desired XYZ ...
4 views

### Rotate quaternion by body yaw

How to change a quaternion's body-fixed yaw? Using Matrix3x3's getRPY and then setRPY doesn'...
53 views

### Angle between two orientations

There are two orientations given, as intrinsic yaw-roll-pitch (rzyx). How to calculate the angle between the "Z" axes of them? Converting the orientations to quaternions or to anything else ...
26 views

### How to transform rtabmap/odom?

I want to compare the visual odometry from RTABMAP (Kinect 2) with ground truth. But it provides odometry rotated 90 degrees around. How to align it with ground truth? Sorry for my English. ...
58 views

### How to convert IMU data to quaternion orientation

Hello I'm trying to fuse my IMU data (and GPS data) with the package robot_localization. Therefore, I have to put my IMU data into a sensor_msgs/Imu message. I know it is possible to convert my IMU ...
4 views

### Wrong argument type when writing quaternion orientation to pose message

Edit: I tried to just simply copy the quaternion values and hardcode them as an orientation coordinates. Results are the same, so maybe problem comes from another part of my grasp msg? I dumped the ...
25 views

### Get link absolute orientation - IMU position

Can anyone advise how to calculate the quaternion orientation of a link? I'm following a somewhat unconventional approach and using an IMU that outputs it's absolute quaternion to measure the position ...
7 views

### TF quaternion rotation problem

My goal is to rotate a quaternion by a yaw angle. q1 is the quaternion that I want to rotate q1 = quaternion_from_euler(math.pi/2, math.pi/4, math.pi/4) I want to ...
5 views

### Ignore yaw of object for pick and place

I am working on a pick and place application where I have to pick a dodecahedron with a vacuum gripper. The camera gives the object pose with respect to the bin it is in. I want to avoid rotating the ...
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### How do I get the displacement vector from one object to another?

I have two objects A and B, each in the form of geometry_msgs/PoseStamped. I would like to calculate the displacement (translation & rotation) vector that I can apply to any (similar) object A' ...
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### transform (x,y,z) coordinate from kinect to /map frame using tf

Hi, I'm tracking an object using a kinect and trying to publish the tf transform of that object in a "/map frame. I'm able to return the object's x, y and depth data using OpenCV. However, I'm ...
38 views

### Get robot position und orientation (in degree) from TF

Hi, I want to get the Position (x, y) and the orientation from my robot. The position should be relative to the map TF. Therefore I used a TransformListener: ...
27 views

### how to get yaw from quaternion values?

Hello everyone, I am new to ROS and this community. I am working with pioneer 3dx robot. My aim is to drive it in a square shape path and return back to its initial position. I am able to get ...
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### Quaternion problem?

Hello, I have a problem with this function: geometry_msgs::Quaternion odom_quat= tf::createQuaternionMsgFromYaw(th); when I give the input value "th" in degree it functions and the robot ...
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### How to transform between the quaternions ( or ERYs)

I know I can transform my quaternion to ERY, and it seems easier to transform between ERYs because it's more direct. For example, I have a vector X (x,y,z) and its ERY is (0,0,a), and I have another ...
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### Quaternion of a 3D vector

My drone is to reach position x,y, z and orient itself along vector3D (ax, by, cz) wrt origin. In order for me to visualize this on rviz I must represent them in quaternion form. I understand that ...
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### Converting a basis to a quaternion python

Hello, I have information in this format (what I assume to be a rotation matrix) xBasis:(-0.923067, -0.221423, -0.314514) ...
105 views

### Get vector representation of x, y, z axis from geometry_msgs Pose

Hi, I have a geometry_msgs/Pose message that contains a certain position and orientation. I want to get the equation of the x axis of that position and orientation. What ROS library function can I use ...