Questions tagged [transforms]
The transforms tag has no usage guidance.
144
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How to approach a target pose via the XY surface normal?
I'm trying to make my panda approach an aruco marker target on the table. However, I also want as a constraint that it does so perpendicular to the target. Given that a pose has an orientation ...
- 43
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47
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World to pixel transformation in Pyrender
I'm trying to transform a point in a 3D world rendered with pyrender to pixel coordinates. The world to camera frame transformation seems to work, however the camera to pixel frame transformation is ...
- 11
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96
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How can I convert Quaternions rotation values into Angular Velocity?
I am currently trying to teleoperate a UR5e robot using a haptic feedback device (3DSystems Touch). I have installed the necessary ROS(noetic) drivers for both devices.
I would like to be able to ...
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1
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275
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From euler angles to rotation matrix and vice versa
I want to check if I am using the correct functions to transform from euler angles to rotation matrix and viceversa. I am using XY’Z” convention of euler intrinsic angles.
As example, I have the ...
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1
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86
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From Euler angles to Rotation matrix Staubli
I want to know the transformation matrix between End effector and Robot base (FK). Staubli gives me x,y,z and Rx,Ry,Rz. Those three Rotations are Euler angles? How could I transform those Euler angles ...
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145
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ROS Transformation between two Coordinate Systems
I have a robot manipulator arm and a tracepen (3D tracked device).
I can get data from the tracepen using tracepenPose, which gives me a ...
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19
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Smooth a timestamped series of translation and quaternion samples
I have a rosbag of transforms (of type TransformStamped) I'd like to smooth a small amount without altering the overall trajectory much, just reduce the higher ...
- 3,244
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173
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Compute tranformation matrix for odom to base_link depending on tracking camera attached relative to base_link
To complete my tf tree, I must broadcast transformation from odom to base_link. I am receiving position from the tracking camera,...
- 111
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488
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transform Pose - undefined reference to std::chrono::time_point, tf2::doTransform
I'm trying to transform frames using tf2 using ros2 rolling but I'm getting this error:
...
- 29
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43
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Calculating Translation and Rotation in Tool Coordinate System
I have a 6-axis robot that moves from P1(x1,y1,z1,q11,q12,q13,q14) to P2(x2,y2,z2,q21,q22,q23,q24) with tool offset T(x,y,z,q1,q2,q3,q4). I know the base coordinates and orientation of both positions. ...
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237
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How to transform given latitude and longitude data to map frame
I am working with a multi sensor RTK-GNSS for localization of my robot.
This is the data I am getting from the GNSS system.
How to relate this data to my robot map frame for navigation?
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24
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v_s quantity in twists
In Modern Robotics v2, we have the following figures:
I don't understand why in Eq. 3.73, we have the given expression for $v_s$. My thinking is:
The position $p$ is the position of the frame $b$ ...
- 161
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26
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Get a rotation to align a vector, n with another vector, a and be able to rotate around a
Let us say I have a rigid body, B. Let us say I have a normal vector n. And let us say I have another direction vector a. I need ...
- 113
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14
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lookupTransform and tf2_echo shows different results
Hi, I am writing code for transformations using apriltag.
tf_buffer_->lookupTransform(tag_frame_, camera_frame_, tf2::TimePointZero);
gives different ...
MrOCW
0
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185
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Publishing transform with rosserial using TF/Odom + display in RVIZ?
I'm trying to model a simple helicopter transform with a spinning rotor in RVIZ. I would prefer it to be timestamped into a single topic.
I've been working through the Odom and TimeTF examples in ...
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647
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ros2: transform pointcloud2 data from one frame to another in python
I have pointcloud2 data related to my lidar_frame. I would like to transform the data to my base_frame to use them with my ICP Algorithm. I found a sample here: https://answers.ros.org/question/291735/...
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97
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How do I convert a set of coordinate and rotation values
I'm an electrical engineer who needs to use a robot for their first time. I have a UR5 that I'm controlling through the rtde interface via Python. It seems that what I'm trying to do must be something ...
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451
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ROS - RViz reports "No transform from [kinect] to [world]" when URDF appears correct
I have specified a URDF relating the world with a table and a Microsoft Kinect mounted on a pole attached to this table.
The URDF parses successfully with check_urdf:
...
- 11
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3
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imu_filter_madgewick frame does not display rotation accurately
I am using the L515 Intel Realsense Camera, and the imu readings function as expected in the realsense-viewer, however when I launch the filter, RVIZ displays the "camera_imu_optical_frame," ...
LiquidTurtle1
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755
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What is the meaning of joint space and configuration space and task space?
I'm reading an article about teleoperation systems and it talks about three spaces that include joint space, configuration space and task space frames. I do not know what these are, can you explain?
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72
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ros2 lookupTransform() to get latest transform
Hello all,
In foxy tf2_ros::Buffer::lookupTransform(),
...
jxl
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2
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212
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sensor breaks tf tree in ROS
I am currently trying to add sensor(lidar) into my robot. I made base for a sensor, link to which sensor is attached through gazebo reference.
The problem is that adding a tag for some reason creates ...
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254
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Sending Universal Robots UR5e to specific place Using Camera
I have a UR5e installed with a simple camera on its end effector. The robot is at a known position (Cartesian pose/angles and joint angles)
Using the camera I took a picture of a QR code and got the ...
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494
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How to republish odometry in different frame?
I have navigation Odometry, but its some how not in the robot body frame. The odometry is being published in world frame, so its not correct. So i need to transform in the robot body frame as that how ...
- 167
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869
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TF is broken when using robot_localization package with only IMU sensor, how to assure that the measured velocity is the one from the robot?
Im using thisrobot_lokalization robot_localization package for the linear velocity. As only sensor input in my case is IMU. I configure the parameters and set the frames as follow
...
- 167
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16
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timeout in lookupTransform behaves differently in rclcpp and rclpy
So I recently got stuck with this strange error that timeout in lookupTransform behaves differently in rclcpp and rclpy. Shortly, I want to acquire transformations at time ...
kurshakuz
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4k
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Static transform difference between command line and launch file
I'm having a problem setting up the static transform between my base_link and my camera.
If I use rosrun tf static_transform_publisher in a different command line the camera is alligned with my axes ...
- 3
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164
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Identifying joints from transformation matrix (DH matrix)
Given a transformation matrix formed using the Denavit Hartenberg method, is there a way to identify joint paramters: for example the order of joints?
I've come across a solution to an exam question ...
- 3
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61
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doubt regarding the base_local_planner::transformGlobalPlan() function
I am trying to understand the base_local_planner::transformGlobalPlan() function.
As per my understanding, the function takes in the global_plan (generated by the <...
- 314
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227
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Significance of fixed_frame parameter in lookupTransform function
I was going through the implementation of the lookupTransform function defined inside the base_local_planner::getGoalPose() function.
What is the significance of ...
- 314
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Signifiance of fixed_frame parameter in lookupTransform function
I was going through the implementation of the lookupTransform function defined inside the base_local_planner::getGoalPose() function.
What is the significance of ...
- 314
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17
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TransformListener x10 higher CPU load in rclpy than rclpp
System info
Operating System:
Docker + Ubuntu 20.04, 10th gen i7
Docker + Ubuntu 20.04, jetson AGX Xavier
ROS2 Version:
Foxy binaries
Steps to reproduce issue
Make sure the system is publishing ...
charlie92
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2
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11
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Can a ROS 2 TF buffer be queried in time-critical code?
Does anybody know if the ROS2 tf buffer belongs in control loops? What's the latency on calling lookupTransform()?
It would be great if it were realtime safe.
...
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179
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Transform Velocity data from sensor frame to world frame
I am new to Robotics and transformation topics. I need help in understanding and solving the below problem.
I have data (surrounding obstacle position, orientation and velocity) which are in sensor ...
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495
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How to make two frames relative to each other
I have a Velodyne and camera that both have transformations specified relative to the origin of the robot.
The original transformations were specified as yaw, roll, pitch, x, y, z. I wrote a script to ...
- 101
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72
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Finding orientation of object in 3D space
Given the above constellation, I have to find the orientation of object B in the coordinate system of Object C. The objects A and B are fixed to a certain place and the object C can move in freely in ...
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42
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Determining Base Configuration Tsb from End-Effector Configuration Tse for youbot
Hello there, hope you are doing great.
Right now I am trying to control youbot to pick and cube and place it to a certain position, on simulation. However, I believe that the reference trajectory is ...
- 328
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21
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Getting the new heading after a Transformation
Lets say I have 2d poses as such (angles in degrees):
world_to_robot = {0, 4, 45} robot_to_object = {4, -4, -45}
From a graph it would be easy to see that:
world_to_object = {4, 8, theta}, what goes ...
- 11
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2
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75
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Compute path in absolute frame from sequence of measurements
I have a sequence of measurements $\{(x_i, y_i, \theta_i)\}_{i = 1 \:...\: N}$. Each of these represents the new pose of the robot seen from the previous pose, i.e. a measurement $(x', y', \theta')$ ...
- 189
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55
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Motion model and homogeneous transformation issue on a drone
I am trying to develop a EKF-SLAM algorithm for a drone, and I want to estimate its position in the inertial/world reference frame. I have as control variables the linear and angular velocities in the ...
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20
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Why would I want to transform a Pose in Frame A using a Transform From B to C?
Using a bit more detail,
Let's say I have a VectorStamped in with frame_id "A", and then I take a StampedTransform with frame_id "B" and child_id "C". It's perfectly ...
aels
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352
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Understanding Twists as 3D Velocities
I am just learning about twists to represent 3D velocities (e.g. of a robot's end-effector), and I have two questions:
1) Wikipedia defines a twist as "an angular velocity around an axis and a linear ...
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1k
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How to calculate rotation angle from 3D points
I have 4 3d points(x, y, z). Using these points how can I calculate rotation angle? Consequently, I want to have a 4x4 transformation matrix including rotation and translation information.
4 points ...
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62
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Reference frame, vector
How do I specify the directions of a unit vector $X_n$ and $Y_n$ of a frame $\{n\}$ at an angle $θ$ relative to a frame $\{a\}$ in the form
$$
X_n=cosθX_a + sinθY_a
$$
$$
Y_n=-sinθX_a+cosθY_a
$$
? Can ...
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3
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27
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How to get list of all tf frames programatically?
Hi all,
I have a question on how to obtain tf frames in a ros node (preferrably Python).
I am aware of the method tf2_ros.Buffer.lookup_transform(), however, one ...
rfn123
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1
answer
56
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Absolute 2D pose from previous pose and measurement
I have a pose $\boldsymbol{x}_0 = (x, y, \theta)$ in an absolute frame, right-handed and centered in (0, 0, 0). I obtain a measurement $\boldsymbol{m} = (\Delta x, \Delta y, \Delta \theta)$ in the ...
- 189
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12
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TF2 ConnectivityException With Connected TF Tree
I'm getting the following error about missing frames, but when I view the TF tree, it shows as a single connected tree. The same error occurs no matter which two frames I use. I don't have enough ...
rwbot
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TF update slow, Sychronize laptop request time with ROS update time
Currently My TF package update extremely slow.
Error pops up for "Lookup would require extrapolation into the future. Requested time xxxxx but the latest data is at time yyyyyyy." ...
Chao Chen
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33
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Lookup would require extrapolation into the future
Lookup would require extrapolation into the future. Requested time 1576960606.876893997 but the latest data is at time 1576960578.443333626.
The request time seems to be correct. However, the latest ...
Chao Chen
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1
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2
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How to transpose and rotate frames and get new coordinates
Hi everyone,
I am new in the ROS world and still don't get some concepts.
Could anyone explain me how to use the transformPose?
Let's assume I have a global frame A and an end-of-efector frame B. Let'...
RobotsAreCool