arXiv subjects

Liu Tianlin

Publications and source records attributed to Liu Tianlin.

3 recordsLinked to original sources

arXiv2025

Embodied Self-Supervised Learning (EMSSL) with Sampling and Training Coordination for Robot Arm Inverse Kinematics Model Learning

Forward and inverse kinematics models are fundamental to robot arms, serving as the basis for the robot arm's operational tasks. However, in model learning of robot arms, especially in the presence of redundant degrees of freedom, inverse model learning is more challenging than forward model learning due to the non-convex problem caused by multiple solutions. In this paper, we propose a framework for autonomous learning of the robot arm inverse model based on embodied self-supervised learning (EMSSL) with sampling and training coordination. We investigate batch inference and parallel computation strategies for data sampling in order to accelerate model learning and propose two approaches for fast adaptation of the robot arm model. A series of experiments demonstrate the effectiveness of the method we proposed. The related code will be available soon.

cs.RO↗

arXiv2025

CEMSSL: Conditional Embodied Self-Supervised Learning is All You Need for High-precision Multi-solution Inverse Kinematics of Robot Arms

In the field of signal processing for robotics, the inverse kinematics of robot arms presents a significant challenge due to multiple solutions caused by redundant degrees of freedom (DOFs). Precision is also a crucial performance indicator for robot arms. Current methods typically rely on conditional deep generative models (CDGMs), which often fall short in precision. In this paper, we propose Conditional Embodied Self-Supervised Learning (CEMSSL) and introduce a unified framework based on CEMSSL for high-precision multi-solution inverse kinematics learning. This framework enhances the precision of existing CDGMs by up to 2-3 orders of magnitude while maintaining their original properties. Furthermore, our method is extendable to other fields of signal processing where obtaining multi-solution data in advance is challenging, as well as to other problems involving multi-solution inverse processes.

cs.RO↗

arXiv2023

High-Precise Robot Arm Manipulation based on Online Iterative Learning and Forward Simulation with Positioning Error Below End-Effector Physical Minimum Displacement

Precision is a crucial performance indicator for robot arms, as high precision manipulation allows for a wider range of applications. Traditional methods for improving robot arm precision rely on error compensation. However, these methods are often not robust and lack adaptability. Learning-based methods offer greater flexibility and adaptability, while current researches show that they often fall short in achieving high precision and struggle to handle many scenarios requiring high precision. In this paper, we propose a novel high-precision robot arm manipulation framework based on online iterative learning and forward simulation, which can achieve positioning error (precision) less than end-effector physical minimum displacement. Additionally, we parallelize multiple high-precision manipulation strategies to better combine online iterative learning and forward simulation. Furthermore, we consider the joint angular resolution of the real robot arm, which is usually neglected in related works. A series of experiments on both simulation and real UR3 robot arm platforms demonstrate that our proposed method is effective and promising. The related code will be available soon.

cs.RO↗