TipMatch:

Cartesian Mapping-Based Retargeting for Dexterous Hand Teleoperation in Tool Manipulation

Abstract

Teleoperating dexterous robot hands for tool manipulation is challenging due to both kinematic mismatches and morphological discrepancies between human and robotic hands. In this paper, we present TipMatch, a novel Cartesian mapping-based retargeting algorithm that compensates for both types of discrepancies. The core of our method lies in leveraging a neural network to predict optimization objectives that account for morphological mismatches, which are difficult to handle with manually designed objectives. Our method ensures reliable gesture alignment for simpler tasks while allowing robust performance on complex tool-use scenarios. Extensive real-world experiments on LeapHand show that TipMatch achieves an average success rate of 84.0% across challenging tasks, maintains high success rates on simpler tasks, and provides larger fingertip workspaces with smoother and more stable mappings compared to existing approaches.

Introductioin

System Design

System Layout

Overview of the TipMatch framework. The Cartesian mapping network first predicts a vector that aligns human and robot fingertip positions. This estimate provides a direct correspondence between the two hand morphologies and serves as input for subsequent retargeting.

The predicted vector is added to the scaled human fingertip position to obtain the target robot fingertip position. This target is then used as the optimization objective for retargeting, which computes the corresponding joint angles. Finally, joint impedance control drives the robotic hand to track the resulting configuration during execution.

Challenging Tool-Use Results

We evaluate our method on five challenging tool-use tasks specifically designed to isolate finger dexterity from arm motion. The robotic arm remains stationary, while all manipulations are executed solely by finger movements. Each task is repeated ten times, and success rates (SR) are reported. As summarized in the table above, our approach demonstrates strong improvements after fine-tuning, achieving an overall success rate of 84.0%, compared to only 36.0% before fine-tuning.

The tasks cover diverse tool manipulations, including chopsticks, brush, syringe, scissors, and spray bottle. Before fine-tuning, performance was limited because the operator had to adopt unnatural or counterintuitive finger gestures, resulting in unstable grasps and frequent failures. For instance, chopsticks and scissors tasks had only a 10% success rate due to the difficulty of consistently reproducing morphology-adapted grasps.

After fine-tuning, our networks reinterpret natural, operator-friendly finger gestures into robot-specific motions adapted to the hand morphology. As a result, success rates increased substantially across all tasks: 60% for chopsticks, 90% for brush, 100% for syringe, 90% for scissors, and 80% for spray bottle use. These results confirm that fine-tuning effectively compensates for human–robot morphological differences, reduces operator burden, and enables robust execution of challenging tool-use tasks.

Comparison of Success Rates Before and After Fine-Tuning
Method Chopsticks Brush Syringe Scissors Spray Overall
Before 1/10 4/10 6/10 1/10 6/10 36.0%
After 6/10 9/10 10/10 9/10 8/10 84.0%

Task Description

Chopsticks: The robotic hand clamps chopsticks and must pick up and hold a fabric toy securely for 5 seconds.

Video