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Lei Ren

14 accepted papers

2026

A Hierarchical Vision-Language and Reinforcement Learning Framework for Robotic Task and Motion Planning in Collaborative Manipulation

RA-L 2026

Vision-language-action models (VLAs) use an end-to-end learning architecture, which can realize the integration of visual perception, semantic understanding and motion control. However, when tackling with the dynamic or long-horizon tasks, VLAs have poor robustness and real-time adjustment ability a

Cited by 2SourceScholar
2026

ChainGPT: Dual-Reasoning Model with Recurrent Depth and Multi-Rank State Updates

ICLR 2026poster

Large language models, constrained by the fixed-depth Transformer architecture, struggle to solve complex reasoning tasks in an end-to-end manner. Existing approaches, such as Chain of Thought, improve reasoning depth to some extent but rely heavily on natural language generation, with computational…

Cited by 0SourceScholar
2026

CoV-Align: Efficient Fine-grained Cross-Modal Alignment with Cohesive Visual Semantics Priority

CVPR 2026

Cross-modal alignment aims to learn semantically consistent latent representations across diverse modalities. Prevailing methods rely on a text-guided aggregation paradigm to achieve fine-grained alignment, while they suffer from redundant patch-word correlations and high computational costs. To add

Cited by 0SourceScholar
2026

Diagnose, Correct, and Learn from Manipulation Failures via Visual Symbols

CVPR 2026

Vision-Language-Action (VLA) models have recently achieved remarkable progress in robotic manipulation, yet they remain limited in failure diagnosis and learning from failures. Additionally, existing failure datasets are mostly generated programmatically in simulation, which limits their generalizat

Cited by 0SourcecodeScholar
2025

Collab-Overcooked: Benchmarking and Evaluating Large Language Models as Collaborative Agents

EMNLP 2025

Large Language Models (LLMs) based agent systems have made great strides in real-world applications beyond traditional NLP tasks. This paper proposes a new LLM-based Multi-Agent System (LLM-MAS) benchmark, Collab-Overcooked, built on the popular Overcooked-AI game with more applicable and challengin

2024

A Lightweight Powered Knee Prosthesis Replicating Early-Stance Knee Flexion During Level Walking

RA-L 2024

Powered knee prostheses promise to improve the mobility of transfemoral amputees by imitating the biomechanics of the missing knee joint. Unfortunately, the heavy weight and short battery life severely limit the application of powered prostheses. Here, we present a lightweight powered knee prosthesi

Cited by 2SourceScholar
2024

Coaxial Integrated Tendon-Driven Actuator: Design, Modeling, Control, and Performance Analysis

RA-L 2024

In this letter, a novel tendon-driven actuator is presented for anthropomimetic robots, mimicking the functionality of a spindle muscle. This actuator can contract and relax, and its tension output can be measured and controlled. The proposed actuator features an innovative space-saving co-axial win

Cited by 0SourceScholar
2023

Tunable Stiffness Caudal Peduncle Leads to Higher Swimming Speed Without Extra Energy

RA-L 2023

Tuning body stiffness like fish to improve swimming efficiency and speed has been adopted by many fish-inspired robotics. However, it is unknown whether the energy saved from improved efficiency can compensate for the energy consumption brought by tuning stiffness itself. To explore this issue, we d

Cited by 23SourceScholar
2022

Design and Validation of a Polycentric Hybrid Knee Prosthesis With Electromagnet-Controlled Mode Transition

RA-L 2022

A hybrid knee prosthesis is proposed in this letter, which consists of a polycentric structure in passive mode for low-torque activities and a single-axis structure in active mode for high-torque activities. A novel mode transition mechanism controls self-holding electromagnets for switching modes b

Cited by 5SourceScholar
2022

Making Pretrained Language Models Good Long-tailed Learners

EMNLP 2022main

Prompt-tuning has shown appealing performance in few-shot classification by virtue of its capability in effectively exploiting pre-trained knowledge. This motivates us to check the hypothesis that prompt-tuning is also a promising choice for long-tailed classification, since the tail classes are int…

2022

Structural Bias for Aspect Sentiment Triplet Extraction

COLING 2022main

Structural bias has recently been exploited for aspect sentiment triplet extraction (ASTE) and led to improved performance. On the other hand, it is recognized that explicitly incorporating structural bias would have a negative impact on efficiency, whereas pretrained language models (PLMs) can alre…

2022

XPrompt: Exploring the Extreme of Prompt Tuning

EMNLP 2022main

Prompt tuning learns soft prompts to condition the frozen Pre-trained Language Models (PLMs) for performing downstream tasks in a parameter-efficient manner. While prompt tuning has gradually reached the performance level of fine-tuning as the model scale increases, there is still a large performanc…

Cited by 39SourcePDFScholar
2021

ASAP: A Chinese Review Dataset Towards Aspect Category Sentiment Analysis and Rating Prediction

NAACL 2021long

Sentiment analysis has attracted increasing attention in e-commerce. The sentiment polarities underlying user reviews are of great value for business intelligence. Aspect category sentiment analysis (ACSA) and review rating prediction (RP) are two essential tasks to detect the fine-to-coarse sentime…