LionRock AI Lab, part of the China Merchants Group's Advanced Technology Research Institute, has released the generalized reasoning model Lion-ER-35B-A3B. This model is designed for visual-linguistic understanding of three-dimensional space, object states, and task execution progress by robots. This was reported by QbitAI on November 4th. The model weights are available on the Hugging Face platform under the Apache 2.0 license.
The Lion-ER model, which stands for LionRock Embodied Reasoner, features a mixture-of-experts architecture with a total of approximately 35 billion parameters, where about 3 billion parameters are active per token. According to the model card, it was fine-tuned based on Qwen3.6-35B-A3B. The lab claims that the model demonstrated improvements across all ten public benchmarks in visual and embodied reasoning, achieving an average weighted score of 65.29, where each score is averaged across four answer samples for one question.
Among specific metrics, the lab noted that the spatial placement metric Where2Place reached 64.28, which is 9.30 points higher than the base model. A result of 64.38 was also achieved on the ERQA embodied reasoning benchmark, exceeding the previous score by 6.19 points. The model scored 89.33 on the SAT spatial reasoning benchmark, and in the ERQA trajectory understanding subcategory, there was an increase of 12.12 points, reaching 68.18.
The lab believes that simply increasing the volume of data for robots does not guarantee an increase in their capabilities. Instead of collecting data on a large scale, the team developed its own embodied data mechanism focused on enhancing capabilities. First, they structured embodied reasoning into eight main areas, including entities, space, time, physics, affordances, tasks, social context, and evidence, as well as 39 more detailed skills. Each skill was then transformed into specific training questions defining the scenes, observations, queries, and evidence needed to obtain a verifiable answer; questions were excluded if visual evidence was insufficient. Human reviewers checked complex examples where the models consistently made errors.
The dataset for supervised training contains 312,380 examples, which are weighted according to capability needs rather than source volume. Then, an evaluation-based loop directs failures back into the data creation process: after excluding labeling or evaluation errors, the team generates new material with the same reasoning pattern from a pool of approximately 4.3 million records covering 31 data sources. In one instance, the model confused an object being higher in an image with it being located higher in three-dimensional space, so the team added scenes with multi-level surfaces.
The model card states that Lion-ER is intended exclusively for research purposes, has not been validated for making critical decisions or controlling autonomous robots, and benchmarking results may not transfer to new environments. The lab also applied a similar methodology to smaller models with base architectures of 4B and 9B.



