Abstract--Humans naturally grasp objects with minimal level required force for stability, whereas robots often rely on rigid, over-squeezing control. T o narrow this gap, we propose a human-inspired physics-conditioned tactile method (Phy-T ac) for force-optimal stable grasping (FOSG) that unifies pose selection, tactile prediction, and force regulation. A physics-based pose selector first identifies feasible contact regions with optimal force distribution based on surface geometry. Then, a physics-conditioned latent diffusion model (Phy-LDM) predicts the tactile imprint under FOSG target. Last, a latent-space LQR controller drives the gripper toward this tactile imprint with minimal actuation, preventing unnecessary compression. Trained on a physics-conditioned tactile dataset covering diverse objects and contact conditions, the proposed Phy-LDM achieves superior tactile prediction accuracy, while the Phy-T ac outperforms fixed-force and GraspNet-based baselines in grasp stability and force efficiency. Experiments on classical robotic platforms demonstrate force-efficient and adaptive manipulation that bridges the gap between robotic and human grasping.

Combining 3D vision with tactile sensing could unlock a greater level of dexterity for robots and improve several manipulation tasks. However, obtaining a close-up 3D view of the location where manipulation contacts occur can be challenging, particularly in confined spaces, cluttered environments, or without installing more sensors on the end effector. In this context, this paper presents StereoTac, a novel vision-based sensor that combines tactile sensing with 3D vision. The proposed sensor relies on stereoscopic vision to capture a 3D representation of the environment before contact and uses photometric stereo to reconstruct the tactile imprint generated by an object during contact. To this end, two cameras were integrated in a single sensor, whose interface is made of a transparent elastomer coated with a thin layer of paint with a level of transparency that can be adjusted by varying the sensor's internal lighting conditions. We describe the sensor's fabrication and evaluate its performance for both tactile perception and 3D vision. Our results show that the proposed sensor can reconstruct a 3D view of a scene just before grasping and perceive the tactile imprint after grasping, allowing for monitoring of the contact during manipulation.