Learning from Demonstration with
Weakly Supervised Disentanglement

Abstract: Robotic manipulation tasks, such as wiping with a soft sponge, require control from multiple rich sensory modalities. Human-robot interaction, aimed at teaching robots, is difficult in this setting as there is potential for mismatch between human and machine comprehension of the rich data streams. We treat the task of interpretable learning from demonstration as an optimisation problem over a probabilistic generative model. To account for the high-dimensionality of the data, a high-capacity neural network is chosen to represent the model. The latent variables in this model are explicitly aligned with high-level notions and concepts that are manifested in a set of demonstrations. We show that such alignment is best achieved through the use of labels from the end user, in an appropriately restricted vocabulary, in contrast to the conventional approach of the designer picking a prior over the latent variables. Our approach is evaluated in the context of a table-top robot manipulation task performed by a PR2 robot -- that of dabbing liquids with a sponge (forcefully pressing a sponge and moving it along a surface). The robot provides visual information, arm joint positions and arm joint efforts.

Multimodal Demonstration Dataset: Link

Motivation & Experimental Setup

lfd-with-weakly-supervised-disentanglement_0_720p.mov

Model Architecture Training & Testing

lfd-with-weakly-supervised-disentanglement_1_720p.mov

Results & Conclusions

lfd-with-weakly-supervised-disentanglement_2_720p.mov

Physical setup for teleoperating a PR2 end-effector through an HTV Vive controller.

Example Pouring Demonstrations from the side and from the robot's PoV

pour in red cup

pour in red cup

pour in blue cup

pour in blue cup

pour from behind

pour from behind

pour sideways

pour sideways

pour partially

pour partially

pour fully

pour fully

Example Dabbing Demonstrations from robot's PoV

press behind

press in front

press hard

press slowly

press quickly