FTACT: Force Torque aware Action Chunking Transformer for Pick-and-Reorient Bottle Task

Abstract

Manipulator robots are increasingly being deployed in retail environments, yet contact rich edge cases still trigger costly human teleoperation. A prominent example is upright lying beverage bottles, where purely visual cues are often insufficient to resolve subtle contact events required for precise manipulation. We present a multimodal Imitation Learning policy that augments the Action Chunking Transformer with force and torque sensing, enabling end-to-end learning over images, joint states, and forces and torques. Deployed on Ghost, single-arm platform by Telexistence Inc, our approach improves Pick-and-Reorient bottle task by detecting and exploiting contact transitions during pressing and placement. Hardware experiments demonstrate greater task success compared to baseline matching the observation space of ACT as an ablation and experiments indicate that force and torque signals are beneficial in the press and place phases where visual observability is limited, supporting the use of interaction forces as a complementary modality for contact rich skills. The results suggest a practical path to scaling retail manipulation by combining modern imitation learning architectures with lightweight force and torque sensing.