Redundancy in kinematics_model and visual_scene


I’m working on an importer for Collada v1.5. I’ve got the impression that there is redundancy in the definition of the kinematics_model, namely in the visual_scene node tree and the kinematic_model. When I’m defining a kinematic do I specify all transformations between the axis and geometries in the node hierarchy of the visual scene. Do I have to repeat the same transformations in the kinematics_model (in between the attachment_full)?
That seems like unnecessary redundancy to me, or am I getting it wrong?

Best regards,

hi stefan,

it’s been a long time ;0)

in collada, the kinematics world is separate from the visual world. The bindings between these two worlds exist in the final scene tag and only the joint transformations themselves are bound. It takes a while to get your head wrapped around this concept, but one way of looking at it is that this allows us to define only a kinematics world. This allows us to exchange such data for quickly testing a robot (or computing kinematic specific properties like IK and reachability) without passing in the entire robot.