Compliant Non-Prehensile Pushing Manipulation

2026-05-25

AI Summary

This work addresses the challenge of achieving safe, non-grasping push manipulation in human–robot coexistence scenarios, where compliance and passive safety during physical interaction are essential. The authors propose a model predictive control framework that integrates a pushing dynamics model with impedance control, optimizing position and velocity setpoints to simultaneously regulate desired pushing forces and adaptively maintain contact points. A key innovation is the first-time incorporation of an energy tank-based passivity filter into the pushing control loop, which dynamically modulates velocity commands to suppress force divergence caused by tracking errors, thereby ensuring bounded system energy and passive safety. The approach is validated in simulation and on two robotic platforms, demonstrating excellent trajectory tracking accuracy, robustness to variations in object parameters, and compliant, passive behavior during human–robot interaction.

Abstract

In this paper, we address the challenge of performing non-prehensile pushing operations with a compliant robotic manipulation system. To ensure safe operations in human-populated environments, robots must comply with external physical interactions and exhibit passive behavior. To achieve this, we extend a state-of-the-art pushing model to integrate it with impedance-controlled robots. We develop a model predictive control framework built upon this model that enables compliant pushing through optimal modulation of the robot's position/velocity set-point, jointly realizing the required pushing force and contact point adaptation to obtain desired object motion. However, external interactions may induce tracking errors, causing a consequent potentially indefinite increase of the pushing force. To prevent this, we integrate an energy tank passivity filter that further modulates the robot velocity set-point to guarantee passivity and avoid uncontrolled energy buildup. The proposed method has been rigorously tested in simulation and validated through experiments on two different robotic systems, demonstrating passive compliance during human-robot interactions and assessing trajectory tracking performance and robustness to variations in the object's physical parameters.

Problem

• compliant manipulation
• non-prehensile pushing
• passivity
• impedance control
• human-robot interaction

Innovation

• compliant manipulation
• non-prehensile pushing
• model predictive control
• impedance control
• passivity filter