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Version: 9.0

Composed Relative Extrinsics

Created by: All Components and Objects


These metrics refer to the error between relative extrinsics measurements (that are composed between components and objects) and the current estimated extrinsic. What does this mean?

  • Components AA and BB have a relative extrinsic formed by object OO represented by ΓOAΓBO\Gamma^A_O \cdot \Gamma^O_B.
  • The current estimated extrinsic between AA and BB is just the transform between the two components, ΓBA\Gamma^A_B.

Ideally, these two should be the same:

ΓBAΓOAΓBO\Gamma^A_B \approx \Gamma^A_O \cdot \Gamma^O_B

...but nothing's perfect in optimization. The error between these two is what we capture in the Composed Relative Extrinsics.

Since MetriCal optimizes for both components and objects, both components and objects have relative constraints. When the kind is a component relative extrinsic, each common_uuid will refer to object spaces. Correspondingly, when the kind is an object relative extrinsic, common_uuid will refer to components.

Composed Relative Extrinsics


Composed relative extrinsics metrics contain the following fields:

kindStringThe kind of relative extrinsic (either "Component" or "Object").
fromUUIDThe UUID of the "from" coordinate frame.
toUUIDThe UUID of the "to" coordinate frame.
extrinsics_differencesAn array of extrinsics objectsThe differences from a unit extrinsic when subtracting the composed world extrinsics from the estimated component or object extrinsic.
common_uuidsAn array of UUIDsThe "common" UUIDs that link a component relative extrinsic or object relative extrinsic.