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TactileLab: Sim-to-Real Dexterous Robot Manipulation with Efficient Shear-Sensitive Tactile Simulation

Yijiong Lin, Wenhao He, Toby Jack, Max Yang, Haoran Li, Nathan F. Lepora

November 2026

Real dual-arm object following, the tactile follower arm keeping contact with a cube moved by the leader arm.

TL;DR TactileLab adds simulated tactile flow, a dense shear field computed from rigid-body contact motion in IsaacLab, so RL policies can feel tangential contact at scale. Trained only in simulation, a LEAP Hand policy using contact depth plus flow makes 1.95 real in-hand rotations in 30 s, against 0.82 with proprioception alone.

What they do

Rigid-body tactile simulators are fast but give only contact depth, which misses shear. Soft-body simulators capture shear but are too slow for large-scale RL. TactileLab, built on IsaacLab, adds simulated tactile flow: a dense 2D field of how each contact point moves tangentially across the sensor, computed from rigid-body contact kinematics. Policies train on depth and flow in simulation and run on real robots by translating real tactile images into the same representation.

How it works

  • Tactile flow. Contact-patch points are projected onto the image plane of a camera modelled inside the sensor. Their image-space displacement over one timestep of sensor-object relative motion is the flow, zero outside contact. No object SDF or elastomer model is needed.
  • Policy learning. A teacher trained with RL on privileged state (object pose, mass, friction, perturbations) is distilled into a student. Its adaptation module, PETS-Net, combines positional-encoded proprioception-action histories with CNN-encoded depth and flow histories through a TCN.
  • Real-to-sim. TacFlowNet, a pix2pix-style conditional GAN, maps two consecutive real tactile images to simulated flow. It is trained on paired real and simulated pressing, sliding, tilting and twisting motions.

Results

  • Simulated in-hand rotation under perturbations: depth plus flow has the lowest fall rate, 11.76% in distribution and 18.69% on unseen objects, against 47.66% and 57.85% for proprioception alone.
  • Shear estimation from six real sensors: for a markerless GelSight Mini, translating to simulated flow cuts translational error from 1.79 to 0.34 mm/s. DIGIT stays weakest (3.33 °/s rotational error).
  • Real dual-arm following, trained on a rigid cube moving in straight lines: 0.91 mm / 0.019 rad error on that cube, up to 6.43 mm / 0.057 rad on a foam brain moving in circles.
  • Real LEAP Hand with four tactile fingertips, trained only on capsules: 1.95 rotations in 30 s with depth plus flow, against 1.70 depth only, 1.61 low-dimensional contact and 0.82 proprioception. On cube-shaped objects: 1.33 against 0.28 for low-dimensional contact.

Limitations

Real-to-sim transfer assumes sticking contact; disturbances that cause slip can lead to unrecoverable states, and slip is not simulated. Handling more diverse object shapes would need larger real-to-sim datasets and geometry-aware transfer models.

Videos

Simulated in-hand rotation and dual-arm tasks with their depth and tactile-flow streams, trained in parallel environments.
Simulated in-hand rotation with each fingertip's contact depth and tactile flow shown alongside.

Figures

From Figure 1: TactileLab overview: GPU-accelerated tactile simulation in IsaacLab with the simulated tactile flow mo...
From Figure 1: TactileLab overview: GPU-accelerated tactile simulation in IsaacLab with the simulated tactile flow modality, tactile policy and representation learning, a real-to-sim transfer pipeline for several real tactile sensors, and sim-to-real deployment on different robots.
From Figure 2: Computing simulated tactile flow. The 3D contact patch is projected onto the tactile image plane, and ...
From Figure 2: Computing simulated tactile flow. The 3D contact patch is projected onto the tactile image plane, and the image-space displacement caused by the relative motion between sensor and object gives a dense flow field; contact depth alone cannot tell sliding from twisting.
From Figure 3: (a) Multimodal tactile policy learning for in-hand manipulation, with unknown random force and torque ...
From Figure 3: (a) Multimodal tactile policy learning for in-hand manipulation, with unknown random force and torque perturbations applied to the object. (b) The PETS-Net architecture for high-dimensional tactile policy learning.
From Figure 13: Snapshots of real-world in-hand rotation of a toy cylinder.
From Figure 13: Snapshots of real-world in-hand rotation of a toy cylinder.
Abstract

Robotic simulators that represent shear within tactile sensing are becoming increasingly important for contact-rich manipulation. However, simulating contact shear with high-fidelity deformable or soft-body simulation is computationally demanding, limiting scalability to large-scale reinforcement learning. Here we introduce \textit{TactileLab}, a scalable multimodal tactile simulation framework built on IsaacLab, with a particular focus on a new optical-flow-based tactile representation termed \textit{simulated tactile flow}. Instead of relying on soft-body physics to model shear deformation, TactileLab uses rigid-body simulation to efficiently estimate dense tangential motion at the contact interface, producing tactile flow fields that encode shear-relevant contact dynamics. This flow field complements geometric features from a contact depth field. We further introduce a novel policy architecture for jointly processing long-horizon proprioceptive signals and rich tactile observations. Across multiple contact-rich tasks, policies trained using simulated tactile flow learn efficiently at scale and exhibit emergent contact-aware behaviours. To facilitate sim-to-real policy deployment, we then propose a novel real-to-sim tactile translation method that maps real tactile image streams to simulated tactile flow and depth fields, together with a new tactile data collection method, and validate it across diverse tactile sensor designs. Using this pipeline, we demonstrate real-world deployment on tasks encompassing dual-arm and dexterous in-hand manipulation. Overall, TactileLab provides an end-to-end sim-to-real framework for scalable tactile policy learning, enabling diverse shear-sensitive manipulation across heterogeneous tactile robotic systems.

Summaries are written automatically from each paper's text. Figures and videos come from the paper and its project page; all credit goes to the authors.