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ros / geometry

Packages for common geometric calculations including the ROS transform library, "tf". Also includes ROS bindings for "bullet" physics engine and "kdl" kinematics/dynamics package.
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Must I sendTransform constantly even if the transform does not change? #190

Closed hyansuper closed 5 years ago

hyansuper commented 5 years ago

I can specify the joint_state_publisher node to subscribe to a source_list so that it republishes my joint state msg. Can I do the same with robot_state_publisher node?

I mean, can I use TransformBroadcaster.sendTransform(...) occasionally when a peticular transform updates, without having to send the transform all the time even if it does not change? The static_transform_publisher node does not fit this scenario because it requires that the transform never change.

Thanks

tfoote commented 5 years ago

The tf system doesn't make assumptions about future values of transforms. If you say what the transform values is at t=1 and t=3 it cannot tell you about what the values is at t=4 until it hears about a value at t>=4

It will do interpolation between values but not try to extrapolate into the future. If you have more questions please ask on answers.ros.org