Optimal Prioritized Dissipation and Closed-Form Damping Limitation under Actuator Constraints for Haptic Interfaces

2026-03-27

AI Summary

This work addresses the trade-off between stability and transparency in haptic interfaces, where conventional approaches often sacrifice transparency due to overly conservative stability constraints and struggle to jointly manage actuator power limits and physical constraints. The authors propose a priority-based dissipative damping limitation method that maximizes transparency while strictly adhering to actuator constraints: it minimizes load by aligning dissipation with an optimal direction and distributes redundant dissipation onto an orthogonal hyperplane. This approach yields, for the first time, a closed-form damping control law for multi-degree-of-freedom parallel systems that simultaneously respects individual actuator power limits and enhances transparency, effectively mitigating issues arising from actuator and motion anisotropy. Built upon the Time-Domain Passivity Analysis (TDPA) framework and leveraging a priority-aware dissipation strategy with analytical solutions, experiments demonstrate stable operation across diverse conditions, achieving significantly improved transparency without violating physical constraints.

Abstract

In haptics, guaranteeing stability is essential to ensure safe interaction with remote or virtual environments. One of the most relevant methods at the state-of-the-art is the Time Domain Passivity Approach (TDPA). However, its high conservatism leads to a significant degradation of transparency. Moreover, the stabilizing action may conflict with the device's physical limitations. State-of-the-art solutions have attempted to address these actuator limits, but they still fail to account simultaneously for the power limits of each actuator while maximizing transparency. This work proposes a new damping limitation method based on prioritized dissipation actions. It prioritizes an optimal dissipation direction that minimizes actuator load, while any excess dissipation is allocated to the orthogonal hyperplane. The solution provides a closed-form formulation and is robust in multi-DoF scenarios, even in the presence of actuator and motion anisotropies. The method is experimentally validated using a parallel haptic interface interacting with a virtual environment and tested under different operating conditions.

Problem

• haptic interfaces
• actuator constraints
• transparency
• stability
• power limits

Innovation

• prioritized dissipation
• closed-form damping limitation
• actuator constraints
• haptic transparency
• multi-DoF stability