Design and Modeling of a HASEL Actuator-Based Micro Parallel Robot

TL;DR

This paper introduces a novel 3-DOF micro parallel robot actuated by HASEL soft actuators, including its design, dynamic modeling, and experimental validation, demonstrating its potential for precise micro-scale motion control.

Contribution

It presents the first integration of HASEL actuators into a micro parallel robot with a comprehensive dynamic model and experimental validation.

Findings

Prototype successfully fabricated and motion measured with laser tracking.

A port-Hamiltonian model accurately captures nonlinear dynamics.

Nonlinear grey-box estimation identified key model parameters.

Abstract

This paper presents the mechatronic design, dynamic modeling, and experimental validation of a three-degree-of-freedom (3-DOF) micro parallel robot featuring a prismatic-spherical (3PS) topology actuated by three Hydraulically Amplified Self-Healing Electrostatic (HASEL) actuators. Each soft actuator provides the prismatic motion of an individual limb, while a compliant interface to the moving platform functions as a spherical joint. A prototype incorporating three base-integrated HASEL actuators was fabricated, and the platform motion was measured using an XY laser-tracking system. For control purposes, a port-Hamiltonian (PH) model, combined with the mechanism's forward kinematics (FKM), is developed to capture the robot's nonlinear dynamic behavior, whereas the inverse kinematics (IKM) is employed to estimate the required actuator displacements. Model parameters were identified using nonlinear grey-box (NLGB) estimation, yielding a compact and control-oriented representation suitable for subsequent controller design.