> For the complete documentation index, see [llms.txt](https://huang-jason.gitbook.io/ros/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://huang-jason.gitbook.io/ros/tf.md).

# PKG - tf

Transform tree defines offsets in terms of both translation and rotation between different coordinate frames.

All transforms move from parent to child.

## Example

We get data from laser, i.e. 'base\_laser' coordinate frame.

We need a way of transforming the laser scan from the 'base\_laser' frame to the 'base\_link' frame.

![](https://548312962-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-Lq83PzYaksJkirwod4I%2F-Lq83Un_qn4pNS1_E1_u%2F-Lq83VQmXsZlKnNtgjau%2Ftf.png?generation=1569962723678184\&alt=media)

translation = (x: -0.1m, y: 0.0m, z: -0.20m).

![](https://548312962-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-Lq83PzYaksJkirwod4I%2F-Lq83Un_qn4pNS1_E1_u%2F-Lq83VQouE_VHFUFAuag%2Ftf_robot.png?generation=1569962723673891\&alt=media)

## tf Tools

$ rosrun tf view\_frames // creates a diagram of frames being broadcast by tf

$ rosrun rqt\_tf\_tree rqt\_tf\_tree