Conversion from absolute actions to delta actions

[vincenzopomponi]

In the latest release of Robomimic v0.5.0, the script robomimic/scripts/conversion/convert_robosuite
introduced support for converting datasets from delta actions → absolute actions.

It would be very useful to also support the inverse operation: converting absolute actions → delta actions.

Motivation

Having this functionality would make it easier to compare methods that use different action representations, and would significantly simplify code development for benchmarking across approaches.

Proposal

Add an option to robomimic/scripts/conversion/convert_robosuite (or a new script) to transform datasets with absolute actions into delta-action datasets.

Ideally, the interface and usage could mirror the current implementation for the delta → absolute conversion.

Thanks for considering this feature!

[amandlek]

Thanks for the suggestion! Happy to accept a PR for this functionality - otherwise we'll consider adding it when we have some time.

cc @vaibhavsaxena11

[zundongke]

How about the action space of the dataset? It will be also helpful to support the reverse operation: getting the reverse action about the action-space